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staging: typec: USB Type-C Port Manager (tcpm)
authorGuenter Roeck <groeck@chromium.org>
Thu, 27 Apr 2017 21:09:56 +0000 (14:09 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 28 Apr 2017 09:28:25 +0000 (11:28 +0200)
This driver implements the USB Type-C Power Delivery state machine
for both source and sink ports. Alternate mode support is not
fully implemented.

The driver attaches to the USB Type-C class code implemented in
the following patches.

usb: typec: add driver for Intel Whiskey Cove PMIC USB Type-C PHY
usb: USB Type-C connector class

This driver only implements the state machine. Lower level drivers are
responsible for
- Reporting VBUS status and activating VBUS
- Setting CC lines and providing CC line status
- Setting line polarity
- Activating and deactivating VCONN
- Setting the current limit
- Activating and deactivating PD message transfers
- Sending and receiving PD messages

The driver provides both a functional API as well as callbacks for
lower level drivers.

Signed-off-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/staging/Kconfig
drivers/staging/Makefile
drivers/staging/typec/Kconfig [new file with mode: 0644]
drivers/staging/typec/Makefile [new file with mode: 0644]
drivers/staging/typec/TODO [new file with mode: 0644]
drivers/staging/typec/pd.h [new file with mode: 0644]
drivers/staging/typec/pd_bdo.h [new file with mode: 0644]
drivers/staging/typec/pd_vdo.h [new file with mode: 0644]
drivers/staging/typec/tcpm.c [new file with mode: 0644]
drivers/staging/typec/tcpm.h [new file with mode: 0644]

index 4c360f8..b1fc626 100644 (file)
@@ -104,4 +104,6 @@ source "drivers/staging/vc04_services/Kconfig"
 
 source "drivers/staging/bcm2835-audio/Kconfig"
 
+source "drivers/staging/typec/Kconfig"
+
 endif # STAGING
index 29cec5a..682127c 100644 (file)
@@ -1,6 +1,7 @@
 # Makefile for staging directory
 
 obj-y                          += media/
+obj-y                          += typec/
 obj-$(CONFIG_PRISM2_USB)       += wlan-ng/
 obj-$(CONFIG_COMEDI)           += comedi/
 obj-$(CONFIG_FB_OLPC_DCON)     += olpc_dcon/
@@ -41,4 +42,3 @@ obj-$(CONFIG_KS7010)          += ks7010/
 obj-$(CONFIG_GREYBUS)          += greybus/
 obj-$(CONFIG_BCM2835_VCHIQ)    += vc04_services/
 obj-$(CONFIG_SND_BCM2835)      += bcm2835-audio/
-
diff --git a/drivers/staging/typec/Kconfig b/drivers/staging/typec/Kconfig
new file mode 100644 (file)
index 0000000..2a98d0d
--- /dev/null
@@ -0,0 +1,11 @@
+menu "USB Power Delivery and Type-C drivers"
+
+config TYPEC_TCPM
+       tristate "USB Type-C Port Controller Manager"
+       depends on USB
+       select TYPEC
+       help
+         The Type-C Port Controller Manager provides a USB PD and USB Type-C
+         state machine for use with Type-C Port Controllers.
+
+endmenu
diff --git a/drivers/staging/typec/Makefile b/drivers/staging/typec/Makefile
new file mode 100644 (file)
index 0000000..4d82c24
--- /dev/null
@@ -0,0 +1 @@
+obj-$(CONFIG_TYPEC_TCPM)       += tcpm.o
diff --git a/drivers/staging/typec/TODO b/drivers/staging/typec/TODO
new file mode 100644 (file)
index 0000000..a8db476
--- /dev/null
@@ -0,0 +1,12 @@
+tcpm:
+- Add documentation (at the very least for the API to low level drivers)
+- Split PD code into separate file
+- Check if it makes sense to use tracepoints instead of debugfs for debug logs
+- Implement Alternate Mode handling
+- Address "#if 0" code if not addressed with the above
+- Validate all comments marked with "XXX"; either address or remove comments
+- Add support for USB PD 3.0. While not mandatory, at least fast role swap
+  as well as authentication support would be very desirable.
+
+Please send patches to Guenter Roeck <linux@roeck-us.net> and copy
+Heikki Krogerus <heikki.krogerus@linux.intel.com>.
diff --git a/drivers/staging/typec/pd.h b/drivers/staging/typec/pd.h
new file mode 100644 (file)
index 0000000..8d97bdb
--- /dev/null
@@ -0,0 +1,281 @@
+/*
+ * Copyright 2015-2017 Google, Inc
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __LINUX_USB_PD_H
+#define __LINUX_USB_PD_H
+
+#include <linux/types.h>
+#include <linux/usb/typec.h>
+
+/* USB PD Messages */
+enum pd_ctrl_msg_type {
+       /* 0 Reserved */
+       PD_CTRL_GOOD_CRC = 1,
+       PD_CTRL_GOTO_MIN = 2,
+       PD_CTRL_ACCEPT = 3,
+       PD_CTRL_REJECT = 4,
+       PD_CTRL_PING = 5,
+       PD_CTRL_PS_RDY = 6,
+       PD_CTRL_GET_SOURCE_CAP = 7,
+       PD_CTRL_GET_SINK_CAP = 8,
+       PD_CTRL_DR_SWAP = 9,
+       PD_CTRL_PR_SWAP = 10,
+       PD_CTRL_VCONN_SWAP = 11,
+       PD_CTRL_WAIT = 12,
+       PD_CTRL_SOFT_RESET = 13,
+       /* 14-15 Reserved */
+};
+
+enum pd_data_msg_type {
+       /* 0 Reserved */
+       PD_DATA_SOURCE_CAP = 1,
+       PD_DATA_REQUEST = 2,
+       PD_DATA_BIST = 3,
+       PD_DATA_SINK_CAP = 4,
+       /* 5-14 Reserved */
+       PD_DATA_VENDOR_DEF = 15,
+};
+
+#define PD_REV10       0x0
+#define PD_REV20       0x1
+
+#define PD_HEADER_CNT_SHIFT    12
+#define PD_HEADER_CNT_MASK     0x7
+#define PD_HEADER_ID_SHIFT     9
+#define PD_HEADER_ID_MASK      0x7
+#define PD_HEADER_PWR_ROLE     BIT(8)
+#define PD_HEADER_REV_SHIFT    6
+#define PD_HEADER_REV_MASK     0x3
+#define PD_HEADER_DATA_ROLE    BIT(5)
+#define PD_HEADER_TYPE_SHIFT   0
+#define PD_HEADER_TYPE_MASK    0xf
+
+#define PD_HEADER(type, pwr, data, id, cnt)                            \
+       ((((type) & PD_HEADER_TYPE_MASK) << PD_HEADER_TYPE_SHIFT) |     \
+        ((pwr) == TYPEC_SOURCE ? PD_HEADER_PWR_ROLE : 0) |             \
+        ((data) == TYPEC_HOST ? PD_HEADER_DATA_ROLE : 0) |             \
+        (PD_REV20 << PD_HEADER_REV_SHIFT) |                            \
+        (((id) & PD_HEADER_ID_MASK) << PD_HEADER_ID_SHIFT) |           \
+        (((cnt) & PD_HEADER_CNT_MASK) << PD_HEADER_CNT_SHIFT))
+
+#define PD_HEADER_LE(type, pwr, data, id, cnt) \
+       cpu_to_le16(PD_HEADER((type), (pwr), (data), (id), (cnt)))
+
+static inline unsigned int pd_header_cnt(u16 header)
+{
+       return (header >> PD_HEADER_CNT_SHIFT) & PD_HEADER_CNT_MASK;
+}
+
+static inline unsigned int pd_header_cnt_le(__le16 header)
+{
+       return pd_header_cnt(le16_to_cpu(header));
+}
+
+static inline unsigned int pd_header_type(u16 header)
+{
+       return (header >> PD_HEADER_TYPE_SHIFT) & PD_HEADER_TYPE_MASK;
+}
+
+static inline unsigned int pd_header_type_le(__le16 header)
+{
+       return pd_header_type(le16_to_cpu(header));
+}
+
+#define PD_MAX_PAYLOAD         7
+
+struct pd_message {
+       __le16 header;
+       __le32 payload[PD_MAX_PAYLOAD];
+} __packed;
+
+/* PDO: Power Data Object */
+#define PDO_MAX_OBJECTS                7
+
+enum pd_pdo_type {
+       PDO_TYPE_FIXED = 0,
+       PDO_TYPE_BATT = 1,
+       PDO_TYPE_VAR = 2,
+};
+
+#define PDO_TYPE_SHIFT         30
+#define PDO_TYPE_MASK          0x3
+
+#define PDO_TYPE(t)    ((t) << PDO_TYPE_SHIFT)
+
+#define PDO_VOLT_MASK          0x3ff
+#define PDO_CURR_MASK          0x3ff
+#define PDO_PWR_MASK           0x3ff
+
+#define PDO_FIXED_DUAL_ROLE    BIT(29) /* Power role swap supported */
+#define PDO_FIXED_SUSPEND      BIT(28) /* USB Suspend supported (Source) */
+#define PDO_FIXED_HIGHER_CAP   BIT(28) /* Requires more than vSafe5V (Sink) */
+#define PDO_FIXED_EXTPOWER     BIT(27) /* Externally powered */
+#define PDO_FIXED_USB_COMM     BIT(26) /* USB communications capable */
+#define PDO_FIXED_DATA_SWAP    BIT(25) /* Data role swap supported */
+#define PDO_FIXED_VOLT_SHIFT   10      /* 50mV units */
+#define PDO_FIXED_CURR_SHIFT   0       /* 10mA units */
+
+#define PDO_FIXED_VOLT(mv)     ((((mv) / 50) & PDO_VOLT_MASK) << PDO_FIXED_VOLT_SHIFT)
+#define PDO_FIXED_CURR(ma)     ((((ma) / 10) & PDO_CURR_MASK) << PDO_FIXED_CURR_SHIFT)
+
+#define PDO_FIXED(mv, ma, flags)                       \
+       (PDO_TYPE(PDO_TYPE_FIXED) | (flags) |           \
+        PDO_FIXED_VOLT(mv) | PDO_FIXED_CURR(ma))
+
+#define PDO_BATT_MAX_VOLT_SHIFT        20      /* 50mV units */
+#define PDO_BATT_MIN_VOLT_SHIFT        10      /* 50mV units */
+#define PDO_BATT_MAX_PWR_SHIFT 0       /* 250mW units */
+
+#define PDO_BATT_MIN_VOLT(mv) ((((mv) / 50) & PDO_VOLT_MASK) << PDO_BATT_MIN_VOLT_SHIFT)
+#define PDO_BATT_MAX_VOLT(mv) ((((mv) / 50) & PDO_VOLT_MASK) << PDO_BATT_MAX_VOLT_SHIFT)
+#define PDO_BATT_MAX_POWER(mw) ((((mw) / 250) & PDO_PWR_MASK) << PDO_BATT_MAX_PWR_SHIFT)
+
+#define PDO_BATT(min_mv, max_mv, max_mw)                       \
+       (PDO_TYPE(PDO_TYPE_BATT) | PDO_BATT_MIN_VOLT(min_mv) |  \
+        PDO_BATT_MAX_VOLT(max_mv) | PDO_BATT_MAX_POWER(max_mw))
+
+#define PDO_VAR_MAX_VOLT_SHIFT 20      /* 50mV units */
+#define PDO_VAR_MIN_VOLT_SHIFT 10      /* 50mV units */
+#define PDO_VAR_MAX_CURR_SHIFT 0       /* 10mA units */
+
+#define PDO_VAR_MIN_VOLT(mv) ((((mv) / 50) & PDO_VOLT_MASK) << PDO_VAR_MIN_VOLT_SHIFT)
+#define PDO_VAR_MAX_VOLT(mv) ((((mv) / 50) & PDO_VOLT_MASK) << PDO_VAR_MAX_VOLT_SHIFT)
+#define PDO_VAR_MAX_CURR(ma) ((((ma) / 10) & PDO_CURR_MASK) << PDO_VAR_MAX_CURR_SHIFT)
+
+#define PDO_VAR(min_mv, max_mv, max_ma)                                \
+       (PDO_TYPE(PDO_TYPE_VAR) | PDO_VAR_MIN_VOLT(min_mv) |    \
+        PDO_VAR_MAX_VOLT(max_mv) | PDO_VAR_MAX_CURR(max_ma))
+
+static inline enum pd_pdo_type pdo_type(u32 pdo)
+{
+       return (pdo >> PDO_TYPE_SHIFT) & PDO_TYPE_MASK;
+}
+
+static inline unsigned int pdo_fixed_voltage(u32 pdo)
+{
+       return ((pdo >> PDO_FIXED_VOLT_SHIFT) & PDO_VOLT_MASK) * 50;
+}
+
+static inline unsigned int pdo_min_voltage(u32 pdo)
+{
+       return ((pdo >> PDO_VAR_MIN_VOLT_SHIFT) & PDO_VOLT_MASK) * 50;
+}
+
+static inline unsigned int pdo_max_voltage(u32 pdo)
+{
+       return ((pdo >> PDO_VAR_MAX_VOLT_SHIFT) & PDO_VOLT_MASK) * 50;
+}
+
+static inline unsigned int pdo_max_current(u32 pdo)
+{
+       return ((pdo >> PDO_VAR_MAX_CURR_SHIFT) & PDO_CURR_MASK) * 10;
+}
+
+static inline unsigned int pdo_max_power(u32 pdo)
+{
+       return ((pdo >> PDO_BATT_MAX_PWR_SHIFT) & PDO_PWR_MASK) * 250;
+}
+
+/* RDO: Request Data Object */
+#define RDO_OBJ_POS_SHIFT      28
+#define RDO_OBJ_POS_MASK       0x7
+#define RDO_GIVE_BACK          BIT(27) /* Supports reduced operating current */
+#define RDO_CAP_MISMATCH       BIT(26) /* Not satisfied by source caps */
+#define RDO_USB_COMM           BIT(25) /* USB communications capable */
+#define RDO_NO_SUSPEND         BIT(24) /* USB Suspend not supported */
+
+#define RDO_PWR_MASK                   0x3ff
+#define RDO_CURR_MASK                  0x3ff
+
+#define RDO_FIXED_OP_CURR_SHIFT                10
+#define RDO_FIXED_MAX_CURR_SHIFT       0
+
+#define RDO_OBJ(idx) (((idx) & RDO_OBJ_POS_MASK) << RDO_OBJ_POS_SHIFT)
+
+#define PDO_FIXED_OP_CURR(ma) ((((ma) / 10) & RDO_CURR_MASK) << RDO_FIXED_OP_CURR_SHIFT)
+#define PDO_FIXED_MAX_CURR(ma) ((((ma) / 10) & RDO_CURR_MASK) << RDO_FIXED_MAX_CURR_SHIFT)
+
+#define RDO_FIXED(idx, op_ma, max_ma, flags)                   \
+       (RDO_OBJ(idx) | (flags) |                               \
+        PDO_FIXED_OP_CURR(op_ma) | PDO_FIXED_MAX_CURR(max_ma))
+
+#define RDO_BATT_OP_PWR_SHIFT          10      /* 250mW units */
+#define RDO_BATT_MAX_PWR_SHIFT         0       /* 250mW units */
+
+#define RDO_BATT_OP_PWR(mw) ((((mw) / 250) & RDO_PWR_MASK) << RDO_BATT_OP_PWR_SHIFT)
+#define RDO_BATT_MAX_PWR(mw) ((((mw) / 250) & RDO_PWR_MASK) << RDO_BATT_MAX_PWR_SHIFT)
+
+#define RDO_BATT(idx, op_mw, max_mw, flags)                    \
+       (RDO_OBJ(idx) | (flags) |                               \
+        RDO_BATT_OP_PWR(op_mw) | RDO_BATT_MAX_PWR(max_mw))
+
+static inline unsigned int rdo_index(u32 rdo)
+{
+       return (rdo >> RDO_OBJ_POS_SHIFT) & RDO_OBJ_POS_MASK;
+}
+
+static inline unsigned int rdo_op_current(u32 rdo)
+{
+       return ((rdo >> RDO_FIXED_OP_CURR_SHIFT) & RDO_CURR_MASK) * 10;
+}
+
+static inline unsigned int rdo_max_current(u32 rdo)
+{
+       return ((rdo >> RDO_FIXED_MAX_CURR_SHIFT) &
+               RDO_CURR_MASK) * 10;
+}
+
+static inline unsigned int rdo_op_power(u32 rdo)
+{
+       return ((rdo >> RDO_BATT_OP_PWR_SHIFT) & RDO_PWR_MASK) * 250;
+}
+
+static inline unsigned int rdo_max_power(u32 rdo)
+{
+       return ((rdo >> RDO_BATT_MAX_PWR_SHIFT) & RDO_PWR_MASK) * 250;
+}
+
+/* USB PD timers and counters */
+#define PD_T_NO_RESPONSE       5000    /* 4.5 - 5.5 seconds */
+#define PD_T_DB_DETECT         10000   /* 10 - 15 seconds */
+#define PD_T_SEND_SOURCE_CAP   150     /* 100 - 200 ms */
+#define PD_T_SENDER_RESPONSE   60      /* 24 - 30 ms, relaxed */
+#define PD_T_SOURCE_ACTIVITY   45
+#define PD_T_SINK_ACTIVITY     135
+#define PD_T_SINK_WAIT_CAP     240
+#define PD_T_PS_TRANSITION     500
+#define PD_T_SRC_TRANSITION    35
+#define PD_T_DRP_SNK           40
+#define PD_T_DRP_SRC           30
+#define PD_T_PS_SOURCE_OFF     920
+#define PD_T_PS_SOURCE_ON      480
+#define PD_T_PS_HARD_RESET     30
+#define PD_T_SRC_RECOVER       760
+#define PD_T_SRC_RECOVER_MAX   1000
+#define PD_T_SRC_TURN_ON       275
+#define PD_T_SAFE_0V           650
+#define PD_T_VCONN_SOURCE_ON   100
+#define PD_T_SINK_REQUEST      100     /* 100 ms minimum */
+#define PD_T_ERROR_RECOVERY    100     /* minimum 25 is insufficient */
+
+#define PD_T_DRP_TRY           100     /* 75 - 150 ms */
+#define PD_T_DRP_TRYWAIT       600     /* 400 - 800 ms */
+
+#define PD_T_CC_DEBOUNCE       200     /* 100 - 200 ms */
+#define PD_T_PD_DEBOUNCE       20      /* 10 - 20 ms */
+
+#define PD_N_CAPS_COUNT                (PD_T_NO_RESPONSE / PD_T_SEND_SOURCE_CAP)
+#define PD_N_HARD_RESET_COUNT  2
+
+#endif /* __LINUX_USB_PD_H */
diff --git a/drivers/staging/typec/pd_bdo.h b/drivers/staging/typec/pd_bdo.h
new file mode 100644 (file)
index 0000000..90b94d9
--- /dev/null
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2015-2017 Google, Inc
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __LINUX_USB_PD_BDO_H
+#define __LINUX_USB_PD_BDO_H
+
+/* BDO : BIST Data Object */
+#define BDO_MODE_RECV          (0 << 28)
+#define BDO_MODE_TRANSMIT      (1 << 28)
+#define BDO_MODE_COUNTERS      (2 << 28)
+#define BDO_MODE_CARRIER0      (3 << 28)
+#define BDO_MODE_CARRIER1      (4 << 28)
+#define BDO_MODE_CARRIER2      (5 << 28)
+#define BDO_MODE_CARRIER3      (6 << 28)
+#define BDO_MODE_EYE           (7 << 28)
+#define BDO_MODE_TESTDATA      (8 << 28)
+
+#define BDO_MODE_MASK(mode)    ((mode) & 0xf0000000)
+
+#endif
diff --git a/drivers/staging/typec/pd_vdo.h b/drivers/staging/typec/pd_vdo.h
new file mode 100644 (file)
index 0000000..dba172e
--- /dev/null
@@ -0,0 +1,249 @@
+/*
+ * Copyright 2015-2017 Google, Inc
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __LINUX_USB_PD_VDO_H
+#define __LINUX_USB_PD_VDO_H
+
+#include "pd.h"
+
+/*
+ * VDO : Vendor Defined Message Object
+ * VDM object is minimum of VDM header + 6 additional data objects.
+ */
+
+/*
+ * VDM header
+ * ----------
+ * <31:16>  :: SVID
+ * <15>     :: VDM type ( 1b == structured, 0b == unstructured )
+ * <14:13>  :: Structured VDM version (can only be 00 == 1.0 currently)
+ * <12:11>  :: reserved
+ * <10:8>   :: object position (1-7 valid ... used for enter/exit mode only)
+ * <7:6>    :: command type (SVDM only?)
+ * <5>      :: reserved (SVDM), command type (UVDM)
+ * <4:0>    :: command
+ */
+#define VDO_MAX_SIZE 7
+#define VDO(vid, type, custom)                         \
+       (((vid) << 16) |                                \
+        ((type) << 15) |                               \
+        ((custom) & 0x7FFF))
+
+#define VDO_SVDM_TYPE          (1 << 15)
+#define VDO_SVDM_VERS(x)       ((x) << 13)
+#define VDO_OPOS(x)            ((x) << 8)
+#define VDO_CMDT(x)            ((x) << 6)
+#define VDO_OPOS_MASK          VDO_OPOS(0x7)
+#define VDO_CMDT_MASK          VDO_CMDT(0x3)
+
+#define CMDT_INIT              0
+#define CMDT_RSP_ACK           1
+#define CMDT_RSP_NAK           2
+#define CMDT_RSP_BUSY          3
+
+/* reserved for SVDM ... for Google UVDM */
+#define VDO_SRC_INITIATOR      (0 << 5)
+#define VDO_SRC_RESPONDER      (1 << 5)
+
+#define CMD_DISCOVER_IDENT     1
+#define CMD_DISCOVER_SVID      2
+#define CMD_DISCOVER_MODES     3
+#define CMD_ENTER_MODE         4
+#define CMD_EXIT_MODE          5
+#define CMD_ATTENTION          6
+
+#define VDO_CMD_VENDOR(x)    (((10 + (x)) & 0x1f))
+
+/* ChromeOS specific commands */
+#define VDO_CMD_VERSION                VDO_CMD_VENDOR(0)
+#define VDO_CMD_SEND_INFO      VDO_CMD_VENDOR(1)
+#define VDO_CMD_READ_INFO      VDO_CMD_VENDOR(2)
+#define VDO_CMD_REBOOT         VDO_CMD_VENDOR(5)
+#define VDO_CMD_FLASH_ERASE    VDO_CMD_VENDOR(6)
+#define VDO_CMD_FLASH_WRITE    VDO_CMD_VENDOR(7)
+#define VDO_CMD_ERASE_SIG      VDO_CMD_VENDOR(8)
+#define VDO_CMD_PING_ENABLE    VDO_CMD_VENDOR(10)
+#define VDO_CMD_CURRENT                VDO_CMD_VENDOR(11)
+#define VDO_CMD_FLIP           VDO_CMD_VENDOR(12)
+#define VDO_CMD_GET_LOG                VDO_CMD_VENDOR(13)
+#define VDO_CMD_CCD_EN         VDO_CMD_VENDOR(14)
+
+#define PD_VDO_VID(vdo)                ((vdo) >> 16)
+#define PD_VDO_SVDM(vdo)       (((vdo) >> 15) & 1)
+#define PD_VDO_OPOS(vdo)       (((vdo) >> 8) & 0x7)
+#define PD_VDO_CMD(vdo)                ((vdo) & 0x1f)
+#define PD_VDO_CMDT(vdo)       (((vdo) >> 6) & 0x3)
+
+/*
+ * SVDM Identity request -> response
+ *
+ * Request is simply properly formatted SVDM header
+ *
+ * Response is 4 data objects:
+ * [0] :: SVDM header
+ * [1] :: Identitiy header
+ * [2] :: Cert Stat VDO
+ * [3] :: (Product | Cable) VDO
+ * [4] :: AMA VDO
+ *
+ */
+#define VDO_INDEX_HDR          0
+#define VDO_INDEX_IDH          1
+#define VDO_INDEX_CSTAT                2
+#define VDO_INDEX_CABLE                3
+#define VDO_INDEX_PRODUCT      3
+#define VDO_INDEX_AMA          4
+
+/*
+ * SVDM Identity Header
+ * --------------------
+ * <31>     :: data capable as a USB host
+ * <30>     :: data capable as a USB device
+ * <29:27>  :: product type
+ * <26>     :: modal operation supported (1b == yes)
+ * <25:16>  :: Reserved, Shall be set to zero
+ * <15:0>   :: USB-IF assigned VID for this cable vendor
+ */
+#define IDH_PTYPE_UNDEF                0
+#define IDH_PTYPE_HUB          1
+#define IDH_PTYPE_PERIPH       2
+#define IDH_PTYPE_PCABLE       3
+#define IDH_PTYPE_ACABLE       4
+#define IDH_PTYPE_AMA          5
+
+#define VDO_IDH(usbh, usbd, ptype, is_modal, vid)              \
+       ((usbh) << 31 | (usbd) << 30 | ((ptype) & 0x7) << 27    \
+        | (is_modal) << 26 | ((vid) & 0xffff))
+
+#define PD_IDH_PTYPE(vdo)      (((vdo) >> 27) & 0x7)
+#define PD_IDH_VID(vdo)                ((vdo) & 0xffff)
+#define PD_IDH_MODAL_SUPP(vdo) ((vdo) & (1 << 26))
+
+/*
+ * Cert Stat VDO
+ * -------------
+ * <31:0>  : USB-IF assigned XID for this cable
+ */
+#define PD_CSTAT_XID(vdo)      (vdo)
+
+/*
+ * Product VDO
+ * -----------
+ * <31:16> : USB Product ID
+ * <15:0>  : USB bcdDevice
+ */
+#define VDO_PRODUCT(pid, bcd)  (((pid) & 0xffff) << 16 | ((bcd) & 0xffff))
+#define PD_PRODUCT_PID(vdo)    (((vdo) >> 16) & 0xffff)
+
+/*
+ * Cable VDO
+ * ---------
+ * <31:28> :: Cable HW version
+ * <27:24> :: Cable FW version
+ * <23:20> :: Reserved, Shall be set to zero
+ * <19:18> :: type-C to Type-A/B/C (00b == A, 01 == B, 10 == C)
+ * <17>    :: Type-C to Plug/Receptacle (0b == plug, 1b == receptacle)
+ * <16:13> :: cable latency (0001 == <10ns(~1m length))
+ * <12:11> :: cable termination type (11b == both ends active VCONN req)
+ * <10>    :: SSTX1 Directionality support (0b == fixed, 1b == cfgable)
+ * <9>     :: SSTX2 Directionality support
+ * <8>     :: SSRX1 Directionality support
+ * <7>     :: SSRX2 Directionality support
+ * <6:5>   :: Vbus current handling capability
+ * <4>     :: Vbus through cable (0b == no, 1b == yes)
+ * <3>     :: SOP" controller present? (0b == no, 1b == yes)
+ * <2:0>   :: USB SS Signaling support
+ */
+#define CABLE_ATYPE            0
+#define CABLE_BTYPE            1
+#define CABLE_CTYPE            2
+#define CABLE_PLUG             0
+#define CABLE_RECEPTACLE       1
+#define CABLE_CURR_1A5         0
+#define CABLE_CURR_3A          1
+#define CABLE_CURR_5A          2
+#define CABLE_USBSS_U2_ONLY    0
+#define CABLE_USBSS_U31_GEN1   1
+#define CABLE_USBSS_U31_GEN2   2
+#define VDO_CABLE(hw, fw, cbl, gdr, lat, term, tx1d, tx2d, rx1d, rx2d, cur,\
+                 vps, sopp, usbss) \
+       (((hw) & 0x7) << 28 | ((fw) & 0x7) << 24 | ((cbl) & 0x3) << 18  \
+        | (gdr) << 17 | ((lat) & 0x7) << 13 | ((term) & 0x3) << 11     \
+        | (tx1d) << 10 | (tx2d) << 9 | (rx1d) << 8 | (rx2d) << 7       \
+        | ((cur) & 0x3) << 5 | (vps) << 4 | (sopp) << 3                \
+        | ((usbss) & 0x7))
+
+/*
+ * AMA VDO
+ * ---------
+ * <31:28> :: Cable HW version
+ * <27:24> :: Cable FW version
+ * <23:12> :: Reserved, Shall be set to zero
+ * <11>    :: SSTX1 Directionality support (0b == fixed, 1b == cfgable)
+ * <10>    :: SSTX2 Directionality support
+ * <9>     :: SSRX1 Directionality support
+ * <8>     :: SSRX2 Directionality support
+ * <7:5>   :: Vconn power
+ * <4>     :: Vconn power required
+ * <3>     :: Vbus power required
+ * <2:0>   :: USB SS Signaling support
+ */
+#define VDO_AMA(hw, fw, tx1d, tx2d, rx1d, rx2d, vcpwr, vcr, vbr, usbss) \
+       (((hw) & 0x7) << 28 | ((fw) & 0x7) << 24                        \
+        | (tx1d) << 11 | (tx2d) << 10 | (rx1d) << 9 | (rx2d) << 8      \
+        | ((vcpwr) & 0x7) << 5 | (vcr) << 4 | (vbr) << 3               \
+        | ((usbss) & 0x7))
+
+#define PD_VDO_AMA_VCONN_REQ(vdo)      (((vdo) >> 4) & 1)
+#define PD_VDO_AMA_VBUS_REQ(vdo)       (((vdo) >> 3) & 1)
+
+#define AMA_VCONN_PWR_1W       0
+#define AMA_VCONN_PWR_1W5      1
+#define AMA_VCONN_PWR_2W       2
+#define AMA_VCONN_PWR_3W       3
+#define AMA_VCONN_PWR_4W       4
+#define AMA_VCONN_PWR_5W       5
+#define AMA_VCONN_PWR_6W       6
+#define AMA_USBSS_U2_ONLY      0
+#define AMA_USBSS_U31_GEN1     1
+#define AMA_USBSS_U31_GEN2     2
+#define AMA_USBSS_BBONLY       3
+
+/*
+ * SVDM Discover SVIDs request -> response
+ *
+ * Request is properly formatted VDM Header with discover SVIDs command.
+ * Response is a set of SVIDs of all all supported SVIDs with all zero's to
+ * mark the end of SVIDs.  If more than 12 SVIDs are supported command SHOULD be
+ * repeated.
+ */
+#define VDO_SVID(svid0, svid1) (((svid0) & 0xffff) << 16 | ((svid1) & 0xffff))
+#define PD_VDO_SVID_SVID0(vdo) ((vdo) >> 16)
+#define PD_VDO_SVID_SVID1(vdo) ((vdo) & 0xffff)
+
+/* USB-IF SIDs */
+#define USB_SID_PD             0xff00 /* power delivery */
+#define USB_SID_DISPLAYPORT    0xff01
+#define USB_SID_MHL            0xff02  /* Mobile High-Definition Link */
+
+/* VDM command timeouts (in ms) */
+
+#define PD_T_VDM_UNSTRUCTURED  500
+#define PD_T_VDM_BUSY          100
+#define PD_T_VDM_WAIT_MODE_E   100
+#define PD_T_VDM_SNDR_RSP      30
+#define PD_T_VDM_E_MODE                25
+#define PD_T_VDM_RCVR_RSP      15
+
+#endif /* __LINUX_USB_PD_VDO_H */
diff --git a/drivers/staging/typec/tcpm.c b/drivers/staging/typec/tcpm.c
new file mode 100644 (file)
index 0000000..abba655
--- /dev/null
@@ -0,0 +1,3465 @@
+/*
+ * Copyright 2015-2017 Google, Inc
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * USB Power Delivery protocol stack.
+ */
+
+#include <linux/completion.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/proc_fs.h>
+#include <linux/sched/clock.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/usb/typec.h>
+#include <linux/workqueue.h>
+
+#include "pd.h"
+#include "pd_vdo.h"
+#include "pd_bdo.h"
+#include "tcpm.h"
+
+#define FOREACH_STATE(S)                       \
+       S(INVALID_STATE),                       \
+       S(DRP_TOGGLING),                        \
+       S(SRC_UNATTACHED),                      \
+       S(SRC_ATTACH_WAIT),                     \
+       S(SRC_ATTACHED),                        \
+       S(SRC_STARTUP),                         \
+       S(SRC_SEND_CAPABILITIES),               \
+       S(SRC_NEGOTIATE_CAPABILITIES),          \
+       S(SRC_TRANSITION_SUPPLY),               \
+       S(SRC_READY),                           \
+       S(SRC_WAIT_NEW_CAPABILITIES),           \
+                                               \
+       S(SNK_UNATTACHED),                      \
+       S(SNK_ATTACH_WAIT),                     \
+       S(SNK_DEBOUNCED),                       \
+       S(SNK_ATTACHED),                        \
+       S(SNK_STARTUP),                         \
+       S(SNK_DISCOVERY),                       \
+       S(SNK_DISCOVERY_DEBOUNCE),              \
+       S(SNK_DISCOVERY_DEBOUNCE_DONE),         \
+       S(SNK_WAIT_CAPABILITIES),               \
+       S(SNK_NEGOTIATE_CAPABILITIES),          \
+       S(SNK_TRANSITION_SINK),                 \
+       S(SNK_TRANSITION_SINK_VBUS),            \
+       S(SNK_READY),                           \
+                                               \
+       S(ACC_UNATTACHED),                      \
+       S(DEBUG_ACC_ATTACHED),                  \
+       S(AUDIO_ACC_ATTACHED),                  \
+       S(AUDIO_ACC_DEBOUNCE),                  \
+                                               \
+       S(HARD_RESET_SEND),                     \
+       S(HARD_RESET_START),                    \
+       S(SRC_HARD_RESET_VBUS_OFF),             \
+       S(SRC_HARD_RESET_VBUS_ON),              \
+       S(SNK_HARD_RESET_SINK_OFF),             \
+       S(SNK_HARD_RESET_WAIT_VBUS),            \
+       S(SNK_HARD_RESET_SINK_ON),              \
+                                               \
+       S(SOFT_RESET),                          \
+       S(SOFT_RESET_SEND),                     \
+                                               \
+       S(DR_SWAP_ACCEPT),                      \
+       S(DR_SWAP_SEND),                        \
+       S(DR_SWAP_SEND_TIMEOUT),                \
+       S(DR_SWAP_CANCEL),                      \
+       S(DR_SWAP_CHANGE_DR),                   \
+                                               \
+       S(PR_SWAP_ACCEPT),                      \
+       S(PR_SWAP_SEND),                        \
+       S(PR_SWAP_SEND_TIMEOUT),                \
+       S(PR_SWAP_CANCEL),                      \
+       S(PR_SWAP_START),                       \
+       S(PR_SWAP_SRC_SNK_TRANSITION_OFF),      \
+       S(PR_SWAP_SRC_SNK_SOURCE_OFF),          \
+       S(PR_SWAP_SRC_SNK_SINK_ON),             \
+       S(PR_SWAP_SNK_SRC_SINK_OFF),            \
+       S(PR_SWAP_SNK_SRC_SOURCE_ON),           \
+                                               \
+       S(VCONN_SWAP_ACCEPT),                   \
+       S(VCONN_SWAP_SEND),                     \
+       S(VCONN_SWAP_SEND_TIMEOUT),             \
+       S(VCONN_SWAP_CANCEL),                   \
+       S(VCONN_SWAP_START),                    \
+       S(VCONN_SWAP_WAIT_FOR_VCONN),           \
+       S(VCONN_SWAP_TURN_ON_VCONN),            \
+       S(VCONN_SWAP_TURN_OFF_VCONN),           \
+                                               \
+       S(SNK_TRY),                             \
+       S(SNK_TRY_WAIT),                        \
+       S(SRC_TRYWAIT),                         \
+       S(SRC_TRYWAIT_UNATTACHED),              \
+                                               \
+       S(SRC_TRY),                             \
+       S(SRC_TRY_DEBOUNCE),                    \
+       S(SNK_TRYWAIT),                         \
+       S(SNK_TRYWAIT_DEBOUNCE),                \
+       S(SNK_TRYWAIT_VBUS),                    \
+       S(BIST_RX),                             \
+                                               \
+       S(ERROR_RECOVERY),                      \
+       S(ERROR_RECOVERY_WAIT_OFF)
+
+#define GENERATE_ENUM(e)       e
+#define GENERATE_STRING(s)     #s
+
+enum tcpm_state {
+       FOREACH_STATE(GENERATE_ENUM)
+};
+
+static const char * const tcpm_states[] = {
+       FOREACH_STATE(GENERATE_STRING)
+};
+
+enum vdm_states {
+       VDM_STATE_ERR_BUSY = -3,
+       VDM_STATE_ERR_SEND = -2,
+       VDM_STATE_ERR_TMOUT = -1,
+       VDM_STATE_DONE = 0,
+       /* Anything >0 represents an active state */
+       VDM_STATE_READY = 1,
+       VDM_STATE_BUSY = 2,
+       VDM_STATE_WAIT_RSP_BUSY = 3,
+};
+
+enum pd_msg_request {
+       PD_MSG_NONE = 0,
+       PD_MSG_CTRL_REJECT,
+       PD_MSG_CTRL_WAIT,
+       PD_MSG_DATA_SINK_CAP,
+       PD_MSG_DATA_SOURCE_CAP,
+};
+
+/* Events from low level driver */
+
+#define TCPM_CC_EVENT          BIT(0)
+#define TCPM_VBUS_EVENT                BIT(1)
+#define TCPM_RESET_EVENT       BIT(2)
+
+#define LOG_BUFFER_ENTRIES     1024
+#define LOG_BUFFER_ENTRY_SIZE  128
+
+/* Alternate mode support */
+
+#define SVID_DISCOVERY_MAX     16
+
+struct pd_mode_data {
+       int svid_index;         /* current SVID index           */
+       int nsvids;
+       u16 svids[SVID_DISCOVERY_MAX];
+       int altmodes;           /* number of alternate modes    */
+       struct typec_altmode_desc altmode_desc[SVID_DISCOVERY_MAX];
+};
+
+struct tcpm_port {
+       struct device *dev;
+
+       struct mutex lock;              /* tcpm state machine lock */
+       struct workqueue_struct *wq;
+
+       struct typec_capability typec_caps;
+       struct typec_port *typec_port;
+
+       struct tcpc_dev *tcpc;
+
+       enum typec_role vconn_role;
+       enum typec_role pwr_role;
+       enum typec_data_role data_role;
+       enum typec_pwr_opmode pwr_opmode;
+
+       struct usb_pd_identity partner_ident;
+       struct typec_partner_desc partner_desc;
+       struct typec_partner *partner;
+
+       enum typec_cc_status cc_req;
+
+       enum typec_cc_status cc1;
+       enum typec_cc_status cc2;
+       enum typec_cc_polarity polarity;
+
+       bool attached;
+       bool connected;
+       bool vbus_present;
+       bool vbus_never_low;
+       bool vbus_source;
+       bool vbus_charge;
+
+       bool send_discover;
+       bool op_vsafe5v;
+
+       int try_role;
+       int try_snk_count;
+       int try_src_count;
+
+       enum pd_msg_request queued_message;
+
+       enum tcpm_state enter_state;
+       enum tcpm_state prev_state;
+       enum tcpm_state state;
+       enum tcpm_state delayed_state;
+       unsigned long delayed_runtime;
+       unsigned long delay_ms;
+
+       spinlock_t pd_event_lock;
+       u32 pd_events;
+
+       struct work_struct event_work;
+       struct delayed_work state_machine;
+       struct delayed_work vdm_state_machine;
+       bool state_machine_running;
+
+       struct completion tx_complete;
+       enum tcpm_transmit_status tx_status;
+
+       struct mutex swap_lock;         /* swap command lock */
+       bool swap_pending;
+       struct completion swap_complete;
+       int swap_status;
+
+       unsigned int message_id;
+       unsigned int caps_count;
+       unsigned int hard_reset_count;
+       bool pd_capable;
+       bool explicit_contract;
+
+       /* Partner capabilities/requests */
+       u32 sink_request;
+       u32 source_caps[PDO_MAX_OBJECTS];
+       unsigned int nr_source_caps;
+       u32 sink_caps[PDO_MAX_OBJECTS];
+       unsigned int nr_sink_caps;
+
+       /* Local capabilities */
+       u32 src_pdo[PDO_MAX_OBJECTS];
+       unsigned int nr_src_pdo;
+       u32 snk_pdo[PDO_MAX_OBJECTS];
+       unsigned int nr_snk_pdo;
+
+       unsigned int max_snk_mv;
+       unsigned int max_snk_ma;
+       unsigned int max_snk_mw;
+       unsigned int operating_snk_mw;
+
+       /* Requested current / voltage */
+       u32 current_limit;
+       u32 supply_voltage;
+
+       u32 bist_request;
+
+       /* PD state for Vendor Defined Messages */
+       enum vdm_states vdm_state;
+       u32 vdm_retries;
+       /* next Vendor Defined Message to send */
+       u32 vdo_data[VDO_MAX_SIZE];
+       u8 vdo_count;
+       /* VDO to retry if UFP responder replied busy */
+       u32 vdo_retry;
+
+       /* Alternate mode data */
+
+       struct pd_mode_data mode_data;
+       struct typec_altmode *partner_altmode[SVID_DISCOVERY_MAX];
+       struct typec_altmode *port_altmode[SVID_DISCOVERY_MAX];
+
+#ifdef CONFIG_DEBUG_FS
+       struct dentry *dentry;
+       struct mutex logbuffer_lock;    /* log buffer access lock */
+       int logbuffer_head;
+       int logbuffer_tail;
+       u8 *logbuffer[LOG_BUFFER_ENTRIES];
+#endif
+};
+
+struct pd_rx_event {
+       struct work_struct work;
+       struct tcpm_port *port;
+       struct pd_message msg;
+};
+
+#define tcpm_cc_is_sink(cc) \
+       ((cc) == TYPEC_CC_RP_DEF || (cc) == TYPEC_CC_RP_1_5 || \
+        (cc) == TYPEC_CC_RP_3_0)
+
+#define tcpm_port_is_sink(port) \
+       ((tcpm_cc_is_sink((port)->cc1) && !tcpm_cc_is_sink((port)->cc2)) || \
+        (tcpm_cc_is_sink((port)->cc2) && !tcpm_cc_is_sink((port)->cc1)))
+
+#define tcpm_cc_is_source(cc) ((cc) == TYPEC_CC_RD)
+#define tcpm_cc_is_audio(cc) ((cc) == TYPEC_CC_RA)
+#define tcpm_cc_is_open(cc) ((cc) == TYPEC_CC_OPEN)
+
+#define tcpm_port_is_source(port) \
+       ((tcpm_cc_is_source((port)->cc1) && \
+        !tcpm_cc_is_source((port)->cc2)) || \
+        (tcpm_cc_is_source((port)->cc2) && \
+         !tcpm_cc_is_source((port)->cc1)))
+
+#define tcpm_port_is_debug(port) \
+       (tcpm_cc_is_source((port)->cc1) && tcpm_cc_is_source((port)->cc2))
+
+#define tcpm_port_is_audio(port) \
+       (tcpm_cc_is_audio((port)->cc1) && tcpm_cc_is_audio((port)->cc2))
+
+#define tcpm_port_is_audio_detached(port) \
+       ((tcpm_cc_is_audio((port)->cc1) && tcpm_cc_is_open((port)->cc2)) || \
+        (tcpm_cc_is_audio((port)->cc2) && tcpm_cc_is_open((port)->cc1)))
+
+#define tcpm_try_snk(port) \
+       ((port)->try_snk_count == 0 && (port)->try_role == TYPEC_SINK)
+
+#define tcpm_try_src(port) \
+       ((port)->try_src_count == 0 && (port)->try_role == TYPEC_SOURCE)
+
+static enum tcpm_state tcpm_default_state(struct tcpm_port *port)
+{
+       if (port->try_role == TYPEC_SINK)
+               return SNK_UNATTACHED;
+       else if (port->try_role == TYPEC_SOURCE)
+               return SRC_UNATTACHED;
+       else if (port->tcpc->config->default_role == TYPEC_SINK)
+               return SNK_UNATTACHED;
+       return SRC_UNATTACHED;
+}
+
+static inline
+struct tcpm_port *typec_cap_to_tcpm(const struct typec_capability *cap)
+{
+       return container_of(cap, struct tcpm_port, typec_caps);
+}
+
+static bool tcpm_port_is_disconnected(struct tcpm_port *port)
+{
+       return (!port->attached && port->cc1 == TYPEC_CC_OPEN &&
+               port->cc2 == TYPEC_CC_OPEN) ||
+              (port->attached && ((port->polarity == TYPEC_POLARITY_CC1 &&
+                                   port->cc1 == TYPEC_CC_OPEN) ||
+                                  (port->polarity == TYPEC_POLARITY_CC2 &&
+                                   port->cc2 == TYPEC_CC_OPEN)));
+}
+
+/*
+ * Logging
+ */
+
+#ifdef CONFIG_DEBUG_FS
+
+static bool tcpm_log_full(struct tcpm_port *port)
+{
+       return port->logbuffer_tail ==
+               (port->logbuffer_head + 1) % LOG_BUFFER_ENTRIES;
+}
+
+static void _tcpm_log(struct tcpm_port *port, const char *fmt, va_list args)
+{
+       char tmpbuffer[LOG_BUFFER_ENTRY_SIZE];
+       u64 ts_nsec = local_clock();
+       unsigned long rem_nsec;
+
+       if (!port->logbuffer[port->logbuffer_head]) {
+               port->logbuffer[port->logbuffer_head] =
+                               kzalloc(LOG_BUFFER_ENTRY_SIZE, GFP_KERNEL);
+               if (!port->logbuffer[port->logbuffer_head])
+                       return;
+       }
+
+       vsnprintf(tmpbuffer, sizeof(tmpbuffer), fmt, args);
+
+       mutex_lock(&port->logbuffer_lock);
+
+       if (tcpm_log_full(port)) {
+               port->logbuffer_head = max(port->logbuffer_head - 1, 0);
+               strcpy(tmpbuffer, "overflow");
+       }
+
+       if (port->logbuffer_head < 0 ||
+           port->logbuffer_head >= LOG_BUFFER_ENTRIES) {
+               dev_warn(port->dev,
+                        "Bad log buffer index %d\n", port->logbuffer_head);
+               goto abort;
+       }
+
+       if (!port->logbuffer[port->logbuffer_head]) {
+               dev_warn(port->dev,
+                        "Log buffer index %d is NULL\n", port->logbuffer_head);
+               goto abort;
+       }
+
+       rem_nsec = do_div(ts_nsec, 1000000000);
+       scnprintf(port->logbuffer[port->logbuffer_head],
+                 LOG_BUFFER_ENTRY_SIZE, "[%5lu.%06lu] %s",
+                 (unsigned long)ts_nsec, rem_nsec / 1000,
+                 tmpbuffer);
+       port->logbuffer_head = (port->logbuffer_head + 1) % LOG_BUFFER_ENTRIES;
+
+abort:
+       mutex_unlock(&port->logbuffer_lock);
+}
+
+static void tcpm_log(struct tcpm_port *port, const char *fmt, ...)
+{
+       va_list args;
+
+       /* Do not log while disconnected and unattached */
+       if (tcpm_port_is_disconnected(port) &&
+           (port->state == SRC_UNATTACHED || port->state == SNK_UNATTACHED ||
+            port->state == DRP_TOGGLING))
+               return;
+
+       va_start(args, fmt);
+       _tcpm_log(port, fmt, args);
+       va_end(args);
+}
+
+static void tcpm_log_force(struct tcpm_port *port, const char *fmt, ...)
+{
+       va_list args;
+
+       va_start(args, fmt);
+       _tcpm_log(port, fmt, args);
+       va_end(args);
+}
+
+static void tcpm_log_source_caps(struct tcpm_port *port)
+{
+       int i;
+
+       for (i = 0; i < port->nr_source_caps; i++) {
+               u32 pdo = port->source_caps[i];
+               enum pd_pdo_type type = pdo_type(pdo);
+               char msg[64];
+
+               switch (type) {
+               case PDO_TYPE_FIXED:
+                       scnprintf(msg, sizeof(msg),
+                                 "%u mV, %u mA [%s%s%s%s%s%s]",
+                                 pdo_fixed_voltage(pdo),
+                                 pdo_max_current(pdo),
+                                 (pdo & PDO_FIXED_DUAL_ROLE) ?
+                                                       "R" : "",
+                                 (pdo & PDO_FIXED_SUSPEND) ?
+                                                       "S" : "",
+                                 (pdo & PDO_FIXED_HIGHER_CAP) ?
+                                                       "H" : "",
+                                 (pdo & PDO_FIXED_USB_COMM) ?
+                                                       "U" : "",
+                                 (pdo & PDO_FIXED_DATA_SWAP) ?
+                                                       "D" : "",
+                                 (pdo & PDO_FIXED_EXTPOWER) ?
+                                                       "E" : "");
+                       break;
+               case PDO_TYPE_VAR:
+                       scnprintf(msg, sizeof(msg),
+                                 "%u-%u mV, %u mA",
+                                 pdo_min_voltage(pdo),
+                                 pdo_max_voltage(pdo),
+                                 pdo_max_current(pdo));
+                       break;
+               case PDO_TYPE_BATT:
+                       scnprintf(msg, sizeof(msg),
+                                 "%u-%u mV, %u mW",
+                                 pdo_min_voltage(pdo),
+                                 pdo_max_voltage(pdo),
+                                 pdo_max_power(pdo));
+                       break;
+               default:
+                       strcpy(msg, "undefined");
+                       break;
+               }
+               tcpm_log(port, " PDO %d: type %d, %s",
+                        i, type, msg);
+       }
+}
+
+static int tcpm_seq_show(struct seq_file *s, void *v)
+{
+       struct tcpm_port *port = (struct tcpm_port *)s->private;
+       int tail;
+
+       mutex_lock(&port->logbuffer_lock);
+       tail = port->logbuffer_tail;
+       while (tail != port->logbuffer_head) {
+               seq_printf(s, "%s\n", port->logbuffer[tail]);
+               tail = (tail + 1) % LOG_BUFFER_ENTRIES;
+       }
+       if (!seq_has_overflowed(s))
+               port->logbuffer_tail = tail;
+       mutex_unlock(&port->logbuffer_lock);
+
+       return 0;
+}
+
+static int tcpm_debug_open(struct inode *inode, struct file *file)
+{
+       return single_open(file, tcpm_seq_show, inode->i_private);
+}
+
+static const struct file_operations tcpm_debug_operations = {
+       .open           = tcpm_debug_open,
+       .llseek         = seq_lseek,
+       .read           = seq_read,
+       .release        = single_release,
+};
+
+static struct dentry *rootdir;
+
+static int tcpm_debugfs_init(struct tcpm_port *port)
+{
+       mutex_init(&port->logbuffer_lock);
+       /* /sys/kernel/debug/tcpm/usbcX */
+       if (!rootdir) {
+               rootdir = debugfs_create_dir("tcpm", NULL);
+               if (!rootdir)
+                       return -ENOMEM;
+       }
+
+       port->dentry = debugfs_create_file(dev_name(port->dev),
+                                          S_IFREG | 0444, rootdir,
+                                          port, &tcpm_debug_operations);
+
+       return 0;
+}
+
+static void tcpm_debugfs_exit(struct tcpm_port *port)
+{
+       debugfs_remove(port->dentry);
+}
+
+#else
+
+static void tcpm_log(const struct tcpm_port *port, const char *fmt, ...) { }
+static void tcpm_log_force(struct tcpm_port *port, const char *fmt, ...) { }
+static void tcpm_log_source_caps(struct tcpm_port *port) { }
+static int tcpm_debugfs_init(const struct tcpm_port *port) { return 0; }
+static void tcpm_debugfs_exit(const struct tcpm_port *port) { }
+
+#endif
+
+static int tcpm_pd_transmit(struct tcpm_port *port,
+                           enum tcpm_transmit_type type,
+                           const struct pd_message *msg)
+{
+       unsigned long timeout;
+       int ret;
+
+       if (msg)
+               tcpm_log(port, "PD TX, header: %#x", le16_to_cpu(msg->header));
+       else
+               tcpm_log(port, "PD TX, type: %#x", type);
+
+       reinit_completion(&port->tx_complete);
+       ret = port->tcpc->pd_transmit(port->tcpc, type, msg);
+       if (ret < 0)
+               return ret;
+
+       mutex_unlock(&port->lock);
+       timeout = wait_for_completion_timeout(&port->tx_complete,
+                               msecs_to_jiffies(PD_T_TCPC_TX_TIMEOUT));
+       mutex_lock(&port->lock);
+       if (!timeout)
+               return -ETIMEDOUT;
+
+       switch (port->tx_status) {
+       case TCPC_TX_SUCCESS:
+               port->message_id = (port->message_id + 1) & PD_HEADER_ID_MASK;
+               return 0;
+       case TCPC_TX_DISCARDED:
+               return -EAGAIN;
+       case TCPC_TX_FAILED:
+       default:
+               return -EIO;
+       }
+}
+
+void tcpm_pd_transmit_complete(struct tcpm_port *port,
+                              enum tcpm_transmit_status status)
+{
+       tcpm_log(port, "PD TX complete, status: %u", status);
+       port->tx_status = status;
+       complete(&port->tx_complete);
+}
+EXPORT_SYMBOL_GPL(tcpm_pd_transmit_complete);
+
+static int tcpm_mux_set(struct tcpm_port *port, enum tcpc_mux_mode mode,
+                       enum tcpc_usb_switch config)
+{
+       int ret = 0;
+
+       tcpm_log(port, "Requesting mux mode %d, config %d, polarity %d",
+                mode, config, port->polarity);
+
+       if (port->tcpc->mux)
+               ret = port->tcpc->mux->set(port->tcpc->mux, mode, config,
+                                          port->polarity);
+
+       return ret;
+}
+
+static int tcpm_set_polarity(struct tcpm_port *port,
+                            enum typec_cc_polarity polarity)
+{
+       int ret;
+
+       tcpm_log(port, "polarity %d", polarity);
+
+       ret = port->tcpc->set_polarity(port->tcpc, polarity);
+       if (ret < 0)
+               return ret;
+
+       port->polarity = polarity;
+
+       return 0;
+}
+
+static int tcpm_set_vconn(struct tcpm_port *port, bool enable)
+{
+       int ret;
+
+       tcpm_log(port, "vconn:=%d", enable);
+
+       ret = port->tcpc->set_vconn(port->tcpc, enable);
+       if (!ret) {
+               port->vconn_role = enable ? TYPEC_SOURCE : TYPEC_SINK;
+               typec_set_vconn_role(port->typec_port, port->vconn_role);
+       }
+
+       return ret;
+}
+
+static u32 tcpm_get_current_limit(struct tcpm_port *port)
+{
+       enum typec_cc_status cc;
+       u32 limit;
+
+       cc = port->polarity ? port->cc2 : port->cc1;
+       switch (cc) {
+       case TYPEC_CC_RP_1_5:
+               limit = 1500;
+               break;
+       case TYPEC_CC_RP_3_0:
+               limit = 3000;
+               break;
+       case TYPEC_CC_RP_DEF:
+       default:
+               limit = 0;
+               break;
+       }
+
+       return limit;
+}
+
+static int tcpm_set_current_limit(struct tcpm_port *port, u32 max_ma, u32 mv)
+{
+       int ret = -EOPNOTSUPP;
+
+       tcpm_log(port, "Setting voltage/current limit %u mV %u mA", mv, max_ma);
+
+       if (port->tcpc->set_current_limit)
+               ret = port->tcpc->set_current_limit(port->tcpc, max_ma, mv);
+
+       return ret;
+}
+
+/*
+ * Determine RP value to set based on maximum current supported
+ * by a port if configured as source.
+ * Returns CC value to report to link partner.
+ */
+static enum typec_cc_status tcpm_rp_cc(struct tcpm_port *port)
+{
+       const u32 *src_pdo = port->src_pdo;
+       int nr_pdo = port->nr_src_pdo;
+       int i;
+
+       /*
+        * Search for first entry with matching voltage.
+        * It should report the maximum supported current.
+        */
+       for (i = 0; i < nr_pdo; i++) {
+               const u32 pdo = src_pdo[i];
+
+               if (pdo_type(pdo) == PDO_TYPE_FIXED &&
+                   pdo_fixed_voltage(pdo) == 5000) {
+                       unsigned int curr = pdo_max_current(pdo);
+
+                       if (curr >= 3000)
+                               return TYPEC_CC_RP_3_0;
+                       else if (curr >= 1500)
+                               return TYPEC_CC_RP_1_5;
+                       return TYPEC_CC_RP_DEF;
+               }
+       }
+
+       return TYPEC_CC_RP_DEF;
+}
+
+static int tcpm_set_attached_state(struct tcpm_port *port, bool attached)
+{
+       return port->tcpc->set_roles(port->tcpc, attached, port->pwr_role,
+                                    port->data_role);
+}
+
+static int tcpm_set_roles(struct tcpm_port *port, bool attached,
+                         enum typec_role role, enum typec_data_role data)
+{
+       int ret;
+
+       if (data == TYPEC_HOST)
+               ret = tcpm_mux_set(port, TYPEC_MUX_USB,
+                                  TCPC_USB_SWITCH_CONNECT);
+       else
+               ret = tcpm_mux_set(port, TYPEC_MUX_NONE,
+                                  TCPC_USB_SWITCH_DISCONNECT);
+       if (ret < 0)
+               return ret;
+
+       ret = port->tcpc->set_roles(port->tcpc, attached, role, data);
+       if (ret < 0)
+               return ret;
+
+       port->pwr_role = role;
+       port->data_role = data;
+       typec_set_data_role(port->typec_port, data);
+       typec_set_pwr_role(port->typec_port, role);
+
+       return 0;
+}
+
+static int tcpm_set_pwr_role(struct tcpm_port *port, enum typec_role role)
+{
+       int ret;
+
+       ret = port->tcpc->set_roles(port->tcpc, true, role,
+                                   port->data_role);
+       if (ret < 0)
+               return ret;
+
+       port->pwr_role = role;
+       typec_set_pwr_role(port->typec_port, role);
+
+       return 0;
+}
+
+static int tcpm_pd_send_source_caps(struct tcpm_port *port)
+{
+       struct pd_message msg;
+       int i;
+
+       memset(&msg, 0, sizeof(msg));
+       if (!port->nr_src_pdo) {
+               /* No source capabilities defined, sink only */
+               msg.header = PD_HEADER_LE(PD_CTRL_REJECT,
+                                         port->pwr_role,
+                                         port->data_role,
+                                         port->message_id, 0);
+       } else {
+               msg.header = PD_HEADER_LE(PD_DATA_SOURCE_CAP,
+                                         port->pwr_role,
+                                         port->data_role,
+                                         port->message_id,
+                                         port->nr_src_pdo);
+       }
+       for (i = 0; i < port->nr_src_pdo; i++)
+               msg.payload[i] = cpu_to_le32(port->src_pdo[i]);
+
+       return tcpm_pd_transmit(port, TCPC_TX_SOP, &msg);
+}
+
+static int tcpm_pd_send_sink_caps(struct tcpm_port *port)
+{
+       struct pd_message msg;
+       int i;
+
+       memset(&msg, 0, sizeof(msg));
+       if (!port->nr_snk_pdo) {
+               /* No sink capabilities defined, source only */
+               msg.header = PD_HEADER_LE(PD_CTRL_REJECT,
+                                         port->pwr_role,
+                                         port->data_role,
+                                         port->message_id, 0);
+       } else {
+               msg.header = PD_HEADER_LE(PD_DATA_SINK_CAP,
+                                         port->pwr_role,
+                                         port->data_role,
+                                         port->message_id,
+                                         port->nr_snk_pdo);
+       }
+       for (i = 0; i < port->nr_snk_pdo; i++)
+               msg.payload[i] = cpu_to_le32(port->snk_pdo[i]);
+
+       return tcpm_pd_transmit(port, TCPC_TX_SOP, &msg);
+}
+
+static void tcpm_set_state(struct tcpm_port *port, enum tcpm_state state,
+                          unsigned int delay_ms)
+{
+       if (delay_ms) {
+               tcpm_log(port, "pending state change %s -> %s @ %u ms",
+                        tcpm_states[port->state], tcpm_states[state],
+                        delay_ms);
+               port->delayed_state = state;
+               mod_delayed_work(port->wq, &port->state_machine,
+                                msecs_to_jiffies(delay_ms));
+               port->delayed_runtime = jiffies + msecs_to_jiffies(delay_ms);
+               port->delay_ms = delay_ms;
+       } else {
+               tcpm_log(port, "state change %s -> %s",
+                        tcpm_states[port->state], tcpm_states[state]);
+               port->delayed_state = INVALID_STATE;
+               port->prev_state = port->state;
+               port->state = state;
+               /*
+                * Don't re-queue the state machine work item if we're currently
+                * in the state machine and we're immediately changing states.
+                * tcpm_state_machine_work() will continue running the state
+                * machine.
+                */
+               if (!port->state_machine_running)
+                       mod_delayed_work(port->wq, &port->state_machine, 0);
+       }
+}
+
+static void tcpm_set_state_cond(struct tcpm_port *port, enum tcpm_state state,
+                               unsigned int delay_ms)
+{
+       if (port->enter_state == port->state)
+               tcpm_set_state(port, state, delay_ms);
+       else
+               tcpm_log(port,
+                        "skipped %sstate change %s -> %s [%u ms], context state %s",
+                        delay_ms ? "delayed " : "",
+                        tcpm_states[port->state], tcpm_states[state],
+                        delay_ms, tcpm_states[port->enter_state]);
+}
+
+static void tcpm_queue_message(struct tcpm_port *port,
+                              enum pd_msg_request message)
+{
+       port->queued_message = message;
+       mod_delayed_work(port->wq, &port->state_machine, 0);
+}
+
+/*
+ * VDM/VDO handling functions
+ */
+static void tcpm_queue_vdm(struct tcpm_port *port, const u32 header,
+                          const u32 *data, int cnt)
+{
+       port->vdo_count = cnt + 1;
+       port->vdo_data[0] = header;
+       memcpy(&port->vdo_data[1], data, sizeof(u32) * cnt);
+       /* Set ready, vdm state machine will actually send */
+       port->vdm_retries = 0;
+       port->vdm_state = VDM_STATE_READY;
+}
+
+static void svdm_consume_identity(struct tcpm_port *port, const __le32 *payload,
+                                 int cnt)
+{
+       u32 vdo = le32_to_cpu(payload[VDO_INDEX_IDH]);
+       u32 product = le32_to_cpu(payload[VDO_INDEX_PRODUCT]);
+
+       memset(&port->mode_data, 0, sizeof(port->mode_data));
+
+#if 0 /* Not really a match */
+       switch (PD_IDH_PTYPE(vdo)) {
+       case IDH_PTYPE_UNDEF:
+               port->partner.type = TYPEC_PARTNER_NONE; /* no longer exists */
+               break;
+       case IDH_PTYPE_HUB:
+               break;
+       case IDH_PTYPE_PERIPH:
+               break;
+       case IDH_PTYPE_PCABLE:
+               break;
+       case IDH_PTYPE_ACABLE:
+               break;
+       case IDH_PTYPE_AMA:
+               port->partner.type = TYPEC_PARTNER_ALTMODE;
+               break;
+       default:
+               break;
+       }
+#endif
+
+       port->partner_ident.id_header = vdo;
+       port->partner_ident.cert_stat = le32_to_cpu(payload[VDO_INDEX_CSTAT]);
+       port->partner_ident.product = product;
+
+       typec_partner_set_identity(port->partner);
+
+       tcpm_log(port, "Identity: %04x:%04x.%04x",
+                PD_IDH_VID(vdo),
+                PD_PRODUCT_PID(product), product & 0xffff);
+}
+
+static bool svdm_consume_svids(struct tcpm_port *port, const __le32 *payload,
+                              int cnt)
+{
+       struct pd_mode_data *pmdata = &port->mode_data;
+       int i;
+
+       for (i = 1; i < cnt; i++) {
+               u32 p = le32_to_cpu(payload[i]);
+               u16 svid;
+
+               svid = (p >> 16) & 0xffff;
+               if (!svid)
+                       return false;
+
+               if (pmdata->nsvids >= SVID_DISCOVERY_MAX)
+                       goto abort;
+
+               pmdata->svids[pmdata->nsvids++] = svid;
+               tcpm_log(port, "SVID %d: 0x%x", pmdata->nsvids, svid);
+
+               svid = p & 0xffff;
+               if (!svid)
+                       return false;
+
+               if (pmdata->nsvids >= SVID_DISCOVERY_MAX)
+                       goto abort;
+
+               pmdata->svids[pmdata->nsvids++] = svid;
+               tcpm_log(port, "SVID %d: 0x%x", pmdata->nsvids, svid);
+       }
+       return true;
+abort:
+       tcpm_log(port, "SVID_DISCOVERY_MAX(%d) too low!", SVID_DISCOVERY_MAX);
+       return false;
+}
+
+static void svdm_consume_modes(struct tcpm_port *port, const __le32 *payload,
+                              int cnt)
+{
+       struct pd_mode_data *pmdata = &port->mode_data;
+       struct typec_altmode_desc *paltmode;
+       struct typec_mode_desc *pmode;
+       int i;
+
+       if (pmdata->altmodes >= ARRAY_SIZE(port->partner_altmode)) {
+               /* Already logged in svdm_consume_svids() */
+               return;
+       }
+
+       paltmode = &pmdata->altmode_desc[pmdata->altmodes];
+       memset(paltmode, 0, sizeof(*paltmode));
+
+       paltmode->svid = pmdata->svids[pmdata->svid_index];
+
+       tcpm_log(port, " Alternate mode %d: SVID 0x%04x",
+                pmdata->altmodes, paltmode->svid);
+
+       for (i = 1; i < cnt && paltmode->n_modes < ALTMODE_MAX_MODES; i++) {
+               pmode = &paltmode->modes[paltmode->n_modes];
+               memset(pmode, 0, sizeof(*pmode));
+               pmode->vdo = le32_to_cpu(payload[i]);
+               pmode->index = i - 1;
+               paltmode->n_modes++;
+               tcpm_log(port, "  VDO %d: 0x%08x",
+                        pmode->index, pmode->vdo);
+       }
+       port->partner_altmode[pmdata->altmodes] =
+               typec_partner_register_altmode(port->partner, paltmode);
+       if (port->partner_altmode[pmdata->altmodes] == NULL) {
+               tcpm_log(port,
+                        "Failed to register alternate modes for SVID 0x%04x",
+                        paltmode->svid);
+               return;
+       }
+       pmdata->altmodes++;
+}
+
+#define supports_modal(port)   PD_IDH_MODAL_SUPP((port)->partner_ident.id_header)
+
+static int tcpm_pd_svdm(struct tcpm_port *port, const __le32 *payload, int cnt,
+                       u32 *response)
+{
+       u32 p0 = le32_to_cpu(payload[0]);
+       int cmd_type = PD_VDO_CMDT(p0);
+       int cmd = PD_VDO_CMD(p0);
+       struct pd_mode_data *modep;
+       int rlen = 0;
+       u16 svid;
+
+       tcpm_log(port, "Rx VDM cmd 0x%x type %d cmd %d len %d",
+                p0, cmd_type, cmd, cnt);
+
+       modep = &port->mode_data;
+
+       switch (cmd_type) {
+       case CMDT_INIT:
+               switch (cmd) {
+               case CMD_DISCOVER_IDENT:
+                       break;
+               case CMD_DISCOVER_SVID:
+                       break;
+               case CMD_DISCOVER_MODES:
+                       break;
+               case CMD_ENTER_MODE:
+                       break;
+               case CMD_EXIT_MODE:
+                       break;
+               case CMD_ATTENTION:
+                       break;
+               default:
+                       break;
+               }
+               if (rlen >= 1) {
+                       response[0] = p0 | VDO_CMDT(CMDT_RSP_ACK);
+               } else if (rlen == 0) {
+                       response[0] = p0 | VDO_CMDT(CMDT_RSP_NAK);
+                       rlen = 1;
+               } else {
+                       response[0] = p0 | VDO_CMDT(CMDT_RSP_BUSY);
+                       rlen = 1;
+               }
+               break;
+       case CMDT_RSP_ACK:
+               /* silently drop message if we are not connected */
+               if (!port->partner)
+                       break;
+
+               switch (cmd) {
+               case CMD_DISCOVER_IDENT:
+                       /* 6.4.4.3.1 */
+                       svdm_consume_identity(port, payload, cnt);
+                       response[0] = VDO(USB_SID_PD, 1, CMD_DISCOVER_SVID);
+                       rlen = 1;
+                       break;
+               case CMD_DISCOVER_SVID:
+                       /* 6.4.4.3.2 */
+                       if (svdm_consume_svids(port, payload, cnt)) {
+                               response[0] = VDO(USB_SID_PD, 1,
+                                                 CMD_DISCOVER_SVID);
+                               rlen = 1;
+                       } else if (modep->nsvids && supports_modal(port)) {
+                               response[0] = VDO(modep->svids[0], 1,
+                                                 CMD_DISCOVER_MODES);
+                               rlen = 1;
+                       }
+                       break;
+               case CMD_DISCOVER_MODES:
+                       /* 6.4.4.3.3 */
+                       svdm_consume_modes(port, payload, cnt);
+                       modep->svid_index++;
+                       if (modep->svid_index < modep->nsvids) {
+                               svid = modep->svids[modep->svid_index];
+                               response[0] = VDO(svid, 1, CMD_DISCOVER_MODES);
+                               rlen = 1;
+                       } else {
+#if 0
+                               response[0] = pd_dfp_enter_mode(port, 0, 0);
+                               if (response[0])
+                                       rlen = 1;
+#endif
+                       }
+                       break;
+               case CMD_ENTER_MODE:
+                       break;
+               default:
+                       break;
+               }
+               break;
+       default:
+               break;
+       }
+
+       return rlen;
+}
+
+static void tcpm_handle_vdm_request(struct tcpm_port *port,
+                                   const __le32 *payload, int cnt)
+{
+       int rlen = 0;
+       u32 response[8] = { };
+       u32 p0 = le32_to_cpu(payload[0]);
+
+       if (port->vdm_state == VDM_STATE_BUSY) {
+               /* If UFP responded busy retry after timeout */
+               if (PD_VDO_CMDT(p0) == CMDT_RSP_BUSY) {
+                       port->vdm_state = VDM_STATE_WAIT_RSP_BUSY;
+                       port->vdo_retry = (p0 & ~VDO_CMDT_MASK) |
+                               CMDT_INIT;
+                       mod_delayed_work(port->wq, &port->vdm_state_machine,
+                                        msecs_to_jiffies(PD_T_VDM_BUSY));
+                       return;
+               }
+               port->vdm_state = VDM_STATE_DONE;
+       }
+
+       if (PD_VDO_SVDM(p0))
+               rlen = tcpm_pd_svdm(port, payload, cnt, response);
+#if 0
+       else
+               rlen = tcpm_pd_custom_vdm(port, cnt, payload, response);
+#endif
+
+       if (rlen > 0) {
+               tcpm_queue_vdm(port, response[0], &response[1], rlen - 1);
+               mod_delayed_work(port->wq, &port->vdm_state_machine, 0);
+       }
+}
+
+static void tcpm_send_vdm(struct tcpm_port *port, u32 vid, int cmd,
+                         const u32 *data, int count)
+{
+       u32 header;
+
+       if (WARN_ON(count > VDO_MAX_SIZE - 1))
+               count = VDO_MAX_SIZE - 1;
+
+       /* set VDM header with VID & CMD */
+       header = VDO(vid, ((vid & USB_SID_PD) == USB_SID_PD) ?
+                       1 : (PD_VDO_CMD(cmd) <= CMD_ATTENTION), cmd);
+       tcpm_queue_vdm(port, header, data, count);
+
+       mod_delayed_work(port->wq, &port->vdm_state_machine, 0);
+}
+
+static unsigned int vdm_ready_timeout(u32 vdm_hdr)
+{
+       unsigned int timeout;
+       int cmd = PD_VDO_CMD(vdm_hdr);
+
+       /* its not a structured VDM command */
+       if (!PD_VDO_SVDM(vdm_hdr))
+               return PD_T_VDM_UNSTRUCTURED;
+
+       switch (PD_VDO_CMDT(vdm_hdr)) {
+       case CMDT_INIT:
+               if (cmd == CMD_ENTER_MODE || cmd == CMD_EXIT_MODE)
+                       timeout = PD_T_VDM_WAIT_MODE_E;
+               else
+                       timeout = PD_T_VDM_SNDR_RSP;
+               break;
+       default:
+               if (cmd == CMD_ENTER_MODE || cmd == CMD_EXIT_MODE)
+                       timeout = PD_T_VDM_E_MODE;
+               else
+                       timeout = PD_T_VDM_RCVR_RSP;
+               break;
+       }
+       return timeout;
+}
+
+static void vdm_run_state_machine(struct tcpm_port *port)
+{
+       struct pd_message msg;
+       int i, res;
+
+       switch (port->vdm_state) {
+       case VDM_STATE_READY:
+               /* Only transmit VDM if attached */
+               if (!port->attached) {
+                       port->vdm_state = VDM_STATE_ERR_BUSY;
+                       break;
+               }
+
+               /*
+                * if there's traffic or we're not in PDO ready state don't send
+                * a VDM.
+                */
+               if (port->state != SRC_READY && port->state != SNK_READY)
+                       break;
+
+               /* Prepare and send VDM */
+               memset(&msg, 0, sizeof(msg));
+               msg.header = PD_HEADER_LE(PD_DATA_VENDOR_DEF,
+                                         port->pwr_role,
+                                         port->data_role,
+                                         port->message_id, port->vdo_count);
+               for (i = 0; i < port->vdo_count; i++)
+                       msg.payload[i] = cpu_to_le32(port->vdo_data[i]);
+               res = tcpm_pd_transmit(port, TCPC_TX_SOP, &msg);
+               if (res < 0) {
+                       port->vdm_state = VDM_STATE_ERR_SEND;
+               } else {
+                       unsigned long timeout;
+
+                       port->vdm_retries = 0;
+                       port->vdm_state = VDM_STATE_BUSY;
+                       timeout = vdm_ready_timeout(port->vdo_data[0]);
+                       mod_delayed_work(port->wq, &port->vdm_state_machine,
+                                        timeout);
+               }
+               break;
+       case VDM_STATE_WAIT_RSP_BUSY:
+               port->vdo_data[0] = port->vdo_retry;
+               port->vdo_count = 1;
+               port->vdm_state = VDM_STATE_READY;
+               break;
+       case VDM_STATE_BUSY:
+               port->vdm_state = VDM_STATE_ERR_TMOUT;
+               break;
+       case VDM_STATE_ERR_SEND:
+               /*
+                * A partner which does not support USB PD will not reply,
+                * so this is not a fatal error. At the same time, some
+                * devices may not return GoodCRC under some circumstances,
+                * so we need to retry.
+                */
+               if (port->vdm_retries < 3) {
+                       tcpm_log(port, "VDM Tx error, retry");
+                       port->vdm_retries++;
+                       port->vdm_state = VDM_STATE_READY;
+               }
+               break;
+       default:
+               break;
+       }
+}
+
+static void vdm_state_machine_work(struct work_struct *work)
+{
+       struct tcpm_port *port = container_of(work, struct tcpm_port,
+                                             vdm_state_machine.work);
+       enum vdm_states prev_state;
+
+       mutex_lock(&port->lock);
+
+       /*
+        * Continue running as long as the port is not busy and there was
+        * a state change.
+        */
+       do {
+               prev_state = port->vdm_state;
+               vdm_run_state_machine(port);
+       } while (port->vdm_state != prev_state &&
+                port->vdm_state != VDM_STATE_BUSY);
+
+       mutex_unlock(&port->lock);
+}
+
+/*
+ * PD (data, control) command handling functions
+ */
+static void tcpm_pd_data_request(struct tcpm_port *port,
+                                const struct pd_message *msg)
+{
+       enum pd_data_msg_type type = pd_header_type_le(msg->header);
+       unsigned int cnt = pd_header_cnt_le(msg->header);
+       unsigned int i;
+
+       switch (type) {
+       case PD_DATA_SOURCE_CAP:
+               if (port->pwr_role != TYPEC_SINK)
+                       break;
+
+               for (i = 0; i < cnt; i++)
+                       port->source_caps[i] = le32_to_cpu(msg->payload[i]);
+
+               port->nr_source_caps = cnt;
+
+               tcpm_log_source_caps(port);
+
+               /*
+                * This message may be received even if VBUS is not
+                * present. This is quite unexpected; see USB PD
+                * specification, sections 8.3.3.6.3.1 and 8.3.3.6.3.2.
+                * However, at the same time, we must be ready to
+                * receive this message and respond to it 15ms after
+                * receiving PS_RDY during power swap operations, no matter
+                * if VBUS is available or not (USB PD specification,
+                * section 6.5.9.2).
+                * So we need to accept the message either way,
+                * but be prepared to keep waiting for VBUS after it was
+                * handled.
+                */
+               tcpm_set_state(port, SNK_NEGOTIATE_CAPABILITIES, 0);
+               break;
+       case PD_DATA_REQUEST:
+               if (port->pwr_role != TYPEC_SOURCE ||
+                   cnt != 1) {
+                       tcpm_queue_message(port, PD_MSG_CTRL_REJECT);
+                       break;
+               }
+               port->sink_request = le32_to_cpu(msg->payload[0]);
+               tcpm_set_state(port, SRC_NEGOTIATE_CAPABILITIES, 0);
+               break;
+       case PD_DATA_SINK_CAP:
+               /* We don't do anything with this at the moment... */
+               for (i = 0; i < cnt; i++)
+                       port->sink_caps[i] = le32_to_cpu(msg->payload[i]);
+               port->nr_sink_caps = cnt;
+               break;
+       case PD_DATA_VENDOR_DEF:
+               tcpm_handle_vdm_request(port, msg->payload, cnt);
+               break;
+       case PD_DATA_BIST:
+               if (port->state == SRC_READY || port->state == SNK_READY) {
+                       port->bist_request = le32_to_cpu(msg->payload[0]);
+                       tcpm_set_state(port, BIST_RX, 0);
+               }
+               break;
+       default:
+               tcpm_log(port, "Unhandled data message type %#x", type);
+               break;
+       }
+}
+
+static void tcpm_pd_ctrl_request(struct tcpm_port *port,
+                                const struct pd_message *msg)
+{
+       enum pd_ctrl_msg_type type = pd_header_type_le(msg->header);
+       enum tcpm_state next_state;
+
+       switch (type) {
+       case PD_CTRL_GOOD_CRC:
+       case PD_CTRL_PING:
+               break;
+       case PD_CTRL_GET_SOURCE_CAP:
+               switch (port->state) {
+               case SRC_READY:
+               case SNK_READY:
+                       tcpm_queue_message(port, PD_MSG_DATA_SOURCE_CAP);
+                       break;
+               default:
+                       tcpm_queue_message(port, PD_MSG_CTRL_REJECT);
+                       break;
+               }
+               break;
+       case PD_CTRL_GET_SINK_CAP:
+               switch (port->state) {
+               case SRC_READY:
+               case SNK_READY:
+                       tcpm_queue_message(port, PD_MSG_DATA_SINK_CAP);
+                       break;
+               default:
+                       tcpm_queue_message(port, PD_MSG_CTRL_REJECT);
+                       break;
+               }
+               break;
+       case PD_CTRL_GOTO_MIN:
+               break;
+       case PD_CTRL_PS_RDY:
+               switch (port->state) {
+               case SNK_TRANSITION_SINK:
+                       if (port->vbus_present) {
+                               tcpm_set_current_limit(port,
+                                                      port->current_limit,
+                                                      port->supply_voltage);
+                               tcpm_set_state(port, SNK_READY, 0);
+                       } else {
+                               /*
+                                * Seen after power swap. Keep waiting for VBUS
+                                * in a transitional state.
+                                */
+                               tcpm_set_state(port,
+                                              SNK_TRANSITION_SINK_VBUS, 0);
+                       }
+                       break;
+               case PR_SWAP_SRC_SNK_SOURCE_OFF:
+                       tcpm_set_state(port, PR_SWAP_SRC_SNK_SINK_ON, 0);
+                       break;
+               case PR_SWAP_SNK_SRC_SINK_OFF:
+                       tcpm_set_state(port, PR_SWAP_SNK_SRC_SOURCE_ON, 0);
+                       break;
+               case VCONN_SWAP_WAIT_FOR_VCONN:
+                       tcpm_set_state(port, VCONN_SWAP_TURN_OFF_VCONN, 0);
+                       break;
+               default:
+                       break;
+               }
+               break;
+       case PD_CTRL_REJECT:
+       case PD_CTRL_WAIT:
+               switch (port->state) {
+               case SNK_NEGOTIATE_CAPABILITIES:
+                       /* USB PD specification, Figure 8-43 */
+                       if (port->explicit_contract)
+                               next_state = SNK_READY;
+                       else
+                               next_state = SNK_WAIT_CAPABILITIES;
+                       tcpm_set_state(port, next_state, 0);
+                       break;
+               case DR_SWAP_SEND:
+                       port->swap_status = (type == PD_CTRL_WAIT ?
+                                            -EAGAIN : -EOPNOTSUPP);
+                       tcpm_set_state(port, DR_SWAP_CANCEL, 0);
+                       break;
+               case PR_SWAP_SEND:
+                       port->swap_status = (type == PD_CTRL_WAIT ?
+                                            -EAGAIN : -EOPNOTSUPP);
+                       tcpm_set_state(port, PR_SWAP_CANCEL, 0);
+                       break;
+               case VCONN_SWAP_SEND:
+                       port->swap_status = (type == PD_CTRL_WAIT ?
+                                            -EAGAIN : -EOPNOTSUPP);
+                       tcpm_set_state(port, VCONN_SWAP_CANCEL, 0);
+                       break;
+               default:
+                       break;
+               }
+               break;
+       case PD_CTRL_ACCEPT:
+               switch (port->state) {
+               case SNK_NEGOTIATE_CAPABILITIES:
+                       tcpm_set_state(port, SNK_TRANSITION_SINK, 0);
+                       break;
+               case SOFT_RESET_SEND:
+                       port->message_id = 0;
+                       if (port->pwr_role == TYPEC_SOURCE)
+                               next_state = SRC_SEND_CAPABILITIES;
+                       else
+                               next_state = SNK_WAIT_CAPABILITIES;
+                       tcpm_set_state(port, next_state, 0);
+                       break;
+               case DR_SWAP_SEND:
+                       tcpm_set_state(port, DR_SWAP_CHANGE_DR, 0);
+                       break;
+               case PR_SWAP_SEND:
+                       tcpm_set_state(port, PR_SWAP_START, 0);
+                       break;
+               case VCONN_SWAP_SEND:
+                       tcpm_set_state(port, VCONN_SWAP_START, 0);
+                       break;
+               default:
+                       break;
+               }
+               break;
+       case PD_CTRL_SOFT_RESET:
+               tcpm_set_state(port, SOFT_RESET, 0);
+               break;
+       case PD_CTRL_DR_SWAP:
+               if (port->typec_caps.type != TYPEC_PORT_DRP) {
+                       tcpm_queue_message(port, PD_MSG_CTRL_REJECT);
+                       break;
+               }
+               /*
+                * XXX
+                * 6.3.9: If an alternate mode is active, a request to swap
+                * alternate modes shall trigger a port reset.
+                */
+               switch (port->state) {
+               case SRC_READY:
+               case SNK_READY:
+                       tcpm_set_state(port, DR_SWAP_ACCEPT, 0);
+                       break;
+               default:
+                       tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
+                       break;
+               }
+               break;
+       case PD_CTRL_PR_SWAP:
+               if (port->typec_caps.type != TYPEC_PORT_DRP) {
+                       tcpm_queue_message(port, PD_MSG_CTRL_REJECT);
+                       break;
+               }
+               switch (port->state) {
+               case SRC_READY:
+               case SNK_READY:
+                       tcpm_set_state(port, PR_SWAP_ACCEPT, 0);
+                       break;
+               default:
+                       tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
+                       break;
+               }
+               break;
+       case PD_CTRL_VCONN_SWAP:
+               switch (port->state) {
+               case SRC_READY:
+               case SNK_READY:
+                       tcpm_set_state(port, VCONN_SWAP_ACCEPT, 0);
+                       break;
+               default:
+                       tcpm_queue_message(port, PD_MSG_CTRL_WAIT);
+                       break;
+               }
+               break;
+       default:
+               tcpm_log(port, "Unhandled ctrl message type %#x", type);
+               break;
+       }
+}
+
+static void tcpm_pd_rx_handler(struct work_struct *work)
+{
+       struct pd_rx_event *event = container_of(work,
+                                                struct pd_rx_event, work);
+       const struct pd_message *msg = &event->msg;
+       unsigned int cnt = pd_header_cnt_le(msg->header);
+       struct tcpm_port *port = event->port;
+
+       mutex_lock(&port->lock);
+
+       tcpm_log(port, "PD RX, header: %#x [%d]", le16_to_cpu(msg->header),
+                port->attached);
+
+       if (port->attached) {
+               /*
+                * If both ends believe to be DFP/host, we have a data role
+                * mismatch.
+                */
+               if (!!(le16_to_cpu(msg->header) & PD_HEADER_DATA_ROLE) ==
+                   (port->data_role == TYPEC_HOST)) {
+                       tcpm_log(port,
+                                "Data role mismatch, initiating error recovery");
+                       tcpm_set_state(port, ERROR_RECOVERY, 0);
+               } else {
+                       if (cnt)
+                               tcpm_pd_data_request(port, msg);
+                       else
+                               tcpm_pd_ctrl_request(port, msg);
+               }
+       }
+
+       mutex_unlock(&port->lock);
+       kfree(event);
+}
+
+void tcpm_pd_receive(struct tcpm_port *port, const struct pd_message *msg)
+{
+       struct pd_rx_event *event;
+
+       event = kzalloc(sizeof(*event), GFP_ATOMIC);
+       if (!event)
+               return;
+
+       INIT_WORK(&event->work, tcpm_pd_rx_handler);
+       event->port = port;
+       memcpy(&event->msg, msg, sizeof(*msg));
+       queue_work(port->wq, &event->work);
+}
+EXPORT_SYMBOL_GPL(tcpm_pd_receive);
+
+static int tcpm_pd_send_control(struct tcpm_port *port,
+                               enum pd_ctrl_msg_type type)
+{
+       struct pd_message msg;
+
+       memset(&msg, 0, sizeof(msg));
+       msg.header = PD_HEADER_LE(type, port->pwr_role,
+                                 port->data_role,
+                                 port->message_id, 0);
+
+       return tcpm_pd_transmit(port, TCPC_TX_SOP, &msg);
+}
+
+/*
+ * Send queued message without affecting state.
+ * Return true if state machine should go back to sleep,
+ * false otherwise.
+ */
+static bool tcpm_send_queued_message(struct tcpm_port *port)
+{
+       enum pd_msg_request queued_message;
+
+       do {
+               queued_message = port->queued_message;
+               port->queued_message = PD_MSG_NONE;
+
+               switch (queued_message) {
+               case PD_MSG_CTRL_WAIT:
+                       tcpm_pd_send_control(port, PD_CTRL_WAIT);
+                       break;
+               case PD_MSG_CTRL_REJECT:
+                       tcpm_pd_send_control(port, PD_CTRL_REJECT);
+                       break;
+               case PD_MSG_DATA_SINK_CAP:
+                       tcpm_pd_send_sink_caps(port);
+                       break;
+               case PD_MSG_DATA_SOURCE_CAP:
+                       tcpm_pd_send_source_caps(port);
+                       break;
+               default:
+                       break;
+               }
+       } while (port->queued_message != PD_MSG_NONE);
+
+       if (port->delayed_state != INVALID_STATE) {
+               if (time_is_after_jiffies(port->delayed_runtime)) {
+                       mod_delayed_work(port->wq, &port->state_machine,
+                                        port->delayed_runtime - jiffies);
+                       return true;
+               }
+               port->delayed_state = INVALID_STATE;
+       }
+       return false;
+}
+
+static int tcpm_pd_check_request(struct tcpm_port *port)
+{
+       u32 pdo, rdo = port->sink_request;
+       unsigned int max, op, pdo_max, index;
+       enum pd_pdo_type type;
+
+       index = rdo_index(rdo);
+       if (!index || index > port->nr_src_pdo)
+               return -EINVAL;
+
+       pdo = port->src_pdo[index - 1];
+       type = pdo_type(pdo);
+       switch (type) {
+       case PDO_TYPE_FIXED:
+       case PDO_TYPE_VAR:
+               max = rdo_max_current(rdo);
+               op = rdo_op_current(rdo);
+               pdo_max = pdo_max_current(pdo);
+
+               if (op > pdo_max)
+                       return -EINVAL;
+               if (max > pdo_max && !(rdo & RDO_CAP_MISMATCH))
+                       return -EINVAL;
+
+               if (type == PDO_TYPE_FIXED)
+                       tcpm_log(port,
+                                "Requested %u mV, %u mA for %u / %u mA",
+                                pdo_fixed_voltage(pdo), pdo_max, op, max);
+               else
+                       tcpm_log(port,
+                                "Requested %u -> %u mV, %u mA for %u / %u mA",
+                                pdo_min_voltage(pdo), pdo_max_voltage(pdo),
+                                pdo_max, op, max);
+               break;
+       case PDO_TYPE_BATT:
+               max = rdo_max_power(rdo);
+               op = rdo_op_power(rdo);
+               pdo_max = pdo_max_power(pdo);
+
+               if (op > pdo_max)
+                       return -EINVAL;
+               if (max > pdo_max && !(rdo & RDO_CAP_MISMATCH))
+                       return -EINVAL;
+               tcpm_log(port,
+                        "Requested %u -> %u mV, %u mW for %u / %u mW",
+                        pdo_min_voltage(pdo), pdo_max_voltage(pdo),
+                        pdo_max, op, max);
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       port->op_vsafe5v = index == 1;
+
+       return 0;
+}
+
+static int tcpm_pd_select_pdo(struct tcpm_port *port)
+{
+       unsigned int i, max_mw = 0, max_mv = 0;
+       int ret = -EINVAL;
+
+       /*
+        * Select the source PDO providing the most power while staying within
+        * the board's voltage limits. Prefer PDO providing exp
+        */
+       for (i = 0; i < port->nr_source_caps; i++) {
+               u32 pdo = port->source_caps[i];
+               enum pd_pdo_type type = pdo_type(pdo);
+               unsigned int mv, ma, mw;
+
+               if (type == PDO_TYPE_FIXED)
+                       mv = pdo_fixed_voltage(pdo);
+               else
+                       mv = pdo_min_voltage(pdo);
+
+               if (type == PDO_TYPE_BATT) {
+                       mw = pdo_max_power(pdo);
+               } else {
+                       ma = min(pdo_max_current(pdo),
+                                port->max_snk_ma);
+                       mw = ma * mv / 1000;
+               }
+
+               /* Perfer higher voltages if available */
+               if ((mw > max_mw || (mw == max_mw && mv > max_mv)) &&
+                   mv <= port->max_snk_mv) {
+                       ret = i;
+                       max_mw = mw;
+                       max_mv = mv;
+               }
+       }
+
+       return ret;
+}
+
+static int tcpm_pd_build_request(struct tcpm_port *port, u32 *rdo)
+{
+       unsigned int mv, ma, mw, flags;
+       unsigned int max_ma, max_mw;
+       enum pd_pdo_type type;
+       int index;
+       u32 pdo;
+
+       index = tcpm_pd_select_pdo(port);
+       if (index < 0)
+               return -EINVAL;
+       pdo = port->source_caps[index];
+       type = pdo_type(pdo);
+
+       if (type == PDO_TYPE_FIXED)
+               mv = pdo_fixed_voltage(pdo);
+       else
+               mv = pdo_min_voltage(pdo);
+
+       /* Select maximum available current within the board's power limit */
+       if (type == PDO_TYPE_BATT) {
+               mw = pdo_max_power(pdo);
+               ma = 1000 * min(mw, port->max_snk_mw) / mv;
+       } else {
+               ma = min(pdo_max_current(pdo),
+                        1000 * port->max_snk_mw / mv);
+       }
+       ma = min(ma, port->max_snk_ma);
+
+       /* XXX: Any other flags need to be set? */
+       flags = 0;
+
+       /* Set mismatch bit if offered power is less than operating power */
+       mw = ma * mv / 1000;
+       max_ma = ma;
+       max_mw = mw;
+       if (mw < port->operating_snk_mw) {
+               flags |= RDO_CAP_MISMATCH;
+               max_mw = port->operating_snk_mw;
+               max_ma = max_mw * 1000 / mv;
+       }
+
+       tcpm_log(port, "cc=%d cc1=%d cc2=%d vbus=%d vconn=%s polarity=%d",
+                port->cc_req, port->cc1, port->cc2, port->vbus_source,
+                port->vconn_role == TYPEC_SOURCE ? "source" : "sink",
+                port->polarity);
+
+       if (type == PDO_TYPE_BATT) {
+               *rdo = RDO_BATT(index + 1, mw, max_mw, flags);
+
+               tcpm_log(port, "Requesting PDO %d: %u mV, %u mW%s",
+                        index, mv, mw,
+                        flags & RDO_CAP_MISMATCH ? " [mismatch]" : "");
+       } else {
+               *rdo = RDO_FIXED(index + 1, ma, max_ma, flags);
+
+               tcpm_log(port, "Requesting PDO %d: %u mV, %u mA%s",
+                        index, mv, ma,
+                        flags & RDO_CAP_MISMATCH ? " [mismatch]" : "");
+       }
+
+       port->current_limit = ma;
+       port->supply_voltage = mv;
+
+       return 0;
+}
+
+static int tcpm_pd_send_request(struct tcpm_port *port)
+{
+       struct pd_message msg;
+       int ret;
+       u32 rdo;
+
+       ret = tcpm_pd_build_request(port, &rdo);
+       if (ret < 0)
+               return ret;
+
+       memset(&msg, 0, sizeof(msg));
+       msg.header = PD_HEADER_LE(PD_DATA_REQUEST,
+                                 port->pwr_role,
+                                 port->data_role,
+                                 port->message_id, 1);
+       msg.payload[0] = cpu_to_le32(rdo);
+
+       return tcpm_pd_transmit(port, TCPC_TX_SOP, &msg);
+}
+
+static int tcpm_set_vbus(struct tcpm_port *port, bool enable)
+{
+       int ret;
+
+       if (enable && port->vbus_charge)
+               return -EINVAL;
+
+       tcpm_log(port, "vbus:=%d charge=%d", enable, port->vbus_charge);
+
+       ret = port->tcpc->set_vbus(port->tcpc, enable, port->vbus_charge);
+       if (ret < 0)
+               return ret;
+
+       port->vbus_source = enable;
+       return 0;
+}
+
+static int tcpm_set_charge(struct tcpm_port *port, bool charge)
+{
+       int ret;
+
+       if (charge && port->vbus_source)
+               return -EINVAL;
+
+       if (charge != port->vbus_charge) {
+               tcpm_log(port, "vbus=%d charge:=%d", port->vbus_source, charge);
+               ret = port->tcpc->set_vbus(port->tcpc, port->vbus_source,
+                                          charge);
+               if (ret < 0)
+                       return ret;
+       }
+       port->vbus_charge = charge;
+       return 0;
+}
+
+static bool tcpm_start_drp_toggling(struct tcpm_port *port)
+{
+       int ret;
+
+       if (port->tcpc->start_drp_toggling &&
+           port->typec_caps.type == TYPEC_PORT_DRP) {
+               tcpm_log_force(port, "Start DRP toggling");
+               ret = port->tcpc->start_drp_toggling(port->tcpc,
+                                                    tcpm_rp_cc(port));
+               if (!ret)
+                       return true;
+       }
+
+       return false;
+}
+
+static void tcpm_set_cc(struct tcpm_port *port, enum typec_cc_status cc)
+{
+       tcpm_log(port, "cc:=%d", cc);
+       port->cc_req = cc;
+       port->tcpc->set_cc(port->tcpc, cc);
+}
+
+static int tcpm_init_vbus(struct tcpm_port *port)
+{
+       int ret;
+
+       ret = port->tcpc->set_vbus(port->tcpc, false, false);
+       port->vbus_source = false;
+       port->vbus_charge = false;
+       return ret;
+}
+
+static int tcpm_init_vconn(struct tcpm_port *port)
+{
+       int ret;
+
+       ret = port->tcpc->set_vconn(port->tcpc, false);
+       port->vconn_role = TYPEC_SINK;
+       return ret;
+}
+
+static void tcpm_typec_connect(struct tcpm_port *port)
+{
+       if (!port->connected) {
+               /* Make sure we don't report stale identity information */
+               memset(&port->partner_ident, 0, sizeof(port->partner_ident));
+               port->partner_desc.usb_pd = port->pd_capable;
+               if (tcpm_port_is_debug(port))
+                       port->partner_desc.accessory = TYPEC_ACCESSORY_DEBUG;
+               else if (tcpm_port_is_audio(port))
+                       port->partner_desc.accessory = TYPEC_ACCESSORY_AUDIO;
+               else
+                       port->partner_desc.accessory = TYPEC_ACCESSORY_NONE;
+               port->partner = typec_register_partner(port->typec_port,
+                                                      &port->partner_desc);
+               port->connected = true;
+       }
+}
+
+static int tcpm_src_attach(struct tcpm_port *port)
+{
+       enum typec_cc_polarity polarity =
+                               port->cc2 == TYPEC_CC_RD ? TYPEC_POLARITY_CC2
+                                                        : TYPEC_POLARITY_CC1;
+       int ret;
+
+       if (port->attached)
+               return 0;
+
+       ret = tcpm_set_polarity(port, polarity);
+       if (ret < 0)
+               return ret;
+
+       ret = tcpm_set_roles(port, true, TYPEC_SOURCE, TYPEC_HOST);
+       if (ret < 0)
+               return ret;
+
+       ret = port->tcpc->set_pd_rx(port->tcpc, true);
+       if (ret < 0)
+               goto out_disable_mux;
+
+       /*
+        * USB Type-C specification, version 1.2,
+        * chapter 4.5.2.2.8.1 (Attached.SRC Requirements)
+        * Enable VCONN only if the non-RD port is set to RA.
+        */
+       if ((polarity == TYPEC_POLARITY_CC1 && port->cc2 == TYPEC_CC_RA) ||
+           (polarity == TYPEC_POLARITY_CC2 && port->cc1 == TYPEC_CC_RA)) {
+               ret = tcpm_set_vconn(port, true);
+               if (ret < 0)
+                       goto out_disable_pd;
+       }
+
+       ret = tcpm_set_vbus(port, true);
+       if (ret < 0)
+               goto out_disable_vconn;
+
+       port->pd_capable = false;
+
+       port->partner = NULL;
+
+       port->attached = true;
+       port->send_discover = true;
+
+       return 0;
+
+out_disable_vconn:
+       tcpm_set_vconn(port, false);
+out_disable_pd:
+       port->tcpc->set_pd_rx(port->tcpc, false);
+out_disable_mux:
+       tcpm_mux_set(port, TYPEC_MUX_NONE, TCPC_USB_SWITCH_DISCONNECT);
+       return ret;
+}
+
+static void tcpm_typec_disconnect(struct tcpm_port *port)
+{
+       if (port->connected) {
+               typec_unregister_partner(port->partner);
+               port->partner = NULL;
+               port->connected = false;
+       }
+}
+
+static void tcpm_unregister_altmodes(struct tcpm_port *port)
+{
+       struct pd_mode_data *modep = &port->mode_data;
+       int i;
+
+       for (i = 0; i < modep->altmodes; i++) {
+               typec_unregister_altmode(port->partner_altmode[i]);
+               port->partner_altmode[i] = NULL;
+       }
+
+       memset(modep, 0, sizeof(*modep));
+}
+
+static void tcpm_reset_port(struct tcpm_port *port)
+{
+       tcpm_unregister_altmodes(port);
+       tcpm_typec_disconnect(port);
+       port->attached = false;
+       port->pd_capable = false;
+
+       port->tcpc->set_pd_rx(port->tcpc, false);
+       tcpm_init_vbus(port);   /* also disables charging */
+       tcpm_init_vconn(port);
+       tcpm_set_current_limit(port, 0, 0);
+       tcpm_set_polarity(port, TYPEC_POLARITY_CC1);
+       tcpm_set_attached_state(port, false);
+       port->try_src_count = 0;
+       port->try_snk_count = 0;
+}
+
+static void tcpm_detach(struct tcpm_port *port)
+{
+       if (!port->attached)
+               return;
+
+       if (tcpm_port_is_disconnected(port))
+               port->hard_reset_count = 0;
+
+       tcpm_reset_port(port);
+}
+
+static void tcpm_src_detach(struct tcpm_port *port)
+{
+       tcpm_detach(port);
+}
+
+static int tcpm_snk_attach(struct tcpm_port *port)
+{
+       int ret;
+
+       if (port->attached)
+               return 0;
+
+       ret = tcpm_set_polarity(port, port->cc2 != TYPEC_CC_OPEN ?
+                               TYPEC_POLARITY_CC2 : TYPEC_POLARITY_CC1);
+       if (ret < 0)
+               return ret;
+
+       ret = tcpm_set_roles(port, true, TYPEC_SINK, TYPEC_DEVICE);
+       if (ret < 0)
+               return ret;
+
+       port->pd_capable = false;
+
+       port->partner = NULL;
+
+       port->attached = true;
+       port->send_discover = true;
+
+       return 0;
+}
+
+static void tcpm_snk_detach(struct tcpm_port *port)
+{
+       tcpm_detach(port);
+
+       /* XXX: (Dis)connect SuperSpeed mux? */
+}
+
+static int tcpm_acc_attach(struct tcpm_port *port)
+{
+       int ret;
+
+       if (port->attached)
+               return 0;
+
+       ret = tcpm_set_roles(port, true, TYPEC_SOURCE, TYPEC_HOST);
+       if (ret < 0)
+               return ret;
+
+       port->partner = NULL;
+
+       tcpm_typec_connect(port);
+
+       port->attached = true;
+
+       return 0;
+}
+
+static void tcpm_acc_detach(struct tcpm_port *port)
+{
+       tcpm_detach(port);
+}
+
+static inline enum tcpm_state hard_reset_state(struct tcpm_port *port)
+{
+       if (port->hard_reset_count < PD_N_HARD_RESET_COUNT)
+               return HARD_RESET_SEND;
+       if (port->pd_capable)
+               return ERROR_RECOVERY;
+       if (port->pwr_role == TYPEC_SOURCE)
+               return SRC_UNATTACHED;
+       if (port->state == SNK_WAIT_CAPABILITIES)
+               return SNK_READY;
+       return SNK_UNATTACHED;
+}
+
+static inline enum tcpm_state ready_state(struct tcpm_port *port)
+{
+       if (port->pwr_role == TYPEC_SOURCE)
+               return SRC_READY;
+       else
+               return SNK_READY;
+}
+
+static inline enum tcpm_state unattached_state(struct tcpm_port *port)
+{
+       if (port->pwr_role == TYPEC_SOURCE)
+               return SRC_UNATTACHED;
+       else
+               return SNK_UNATTACHED;
+}
+
+static void tcpm_check_send_discover(struct tcpm_port *port)
+{
+       if (port->data_role == TYPEC_HOST && port->send_discover &&
+           port->pd_capable) {
+               tcpm_send_vdm(port, USB_SID_PD, CMD_DISCOVER_IDENT, NULL, 0);
+               port->send_discover = false;
+       }
+}
+
+static void tcpm_swap_complete(struct tcpm_port *port, int result)
+{
+       if (port->swap_pending) {
+               port->swap_status = result;
+               port->swap_pending = false;
+               complete(&port->swap_complete);
+       }
+}
+
+static void run_state_machine(struct tcpm_port *port)
+{
+       int ret;
+
+       port->enter_state = port->state;
+       switch (port->state) {
+       case DRP_TOGGLING:
+               break;
+       /* SRC states */
+       case SRC_UNATTACHED:
+               tcpm_swap_complete(port, -ENOTCONN);
+               tcpm_src_detach(port);
+               if (tcpm_start_drp_toggling(port)) {
+                       tcpm_set_state(port, DRP_TOGGLING, 0);
+                       break;
+               }
+               tcpm_set_cc(port, tcpm_rp_cc(port));
+               if (port->typec_caps.type == TYPEC_PORT_DRP)
+                       tcpm_set_state(port, SNK_UNATTACHED, PD_T_DRP_SNK);
+               break;
+       case SRC_ATTACH_WAIT:
+               if (tcpm_port_is_debug(port))
+                       tcpm_set_state(port, DEBUG_ACC_ATTACHED,
+                                      PD_T_CC_DEBOUNCE);
+               else if (tcpm_port_is_audio(port))
+                       tcpm_set_state(port, AUDIO_ACC_ATTACHED,
+                                      PD_T_CC_DEBOUNCE);
+               else if (tcpm_port_is_source(port))
+                       tcpm_set_state(port,
+                                      tcpm_try_snk(port) ? SNK_TRY
+                                                         : SRC_ATTACHED,
+                                      PD_T_CC_DEBOUNCE);
+               break;
+
+       case SNK_TRY:
+               port->try_snk_count++;
+               /*
+                * Requirements:
+                * - Do not drive vconn or vbus
+                * - Terminate CC pins (both) to Rd
+                * Action:
+                * - Wait for tDRPTry (PD_T_DRP_TRY).
+                *   Until then, ignore any state changes.
+                */
+               tcpm_set_cc(port, TYPEC_CC_RD);
+               tcpm_set_state(port, SNK_TRY_WAIT, PD_T_DRP_TRY);
+               break;
+       case SNK_TRY_WAIT:
+               if (port->vbus_present && tcpm_port_is_sink(port)) {
+                       tcpm_set_state(port, SNK_ATTACHED, 0);
+                       break;
+               }
+               if (!tcpm_port_is_sink(port)) {
+                       tcpm_set_state(port, SRC_TRYWAIT,
+                                      PD_T_PD_DEBOUNCE);
+                       break;
+               }
+               /* No vbus, cc state is sink or open */
+               tcpm_set_state(port, SRC_TRYWAIT_UNATTACHED, PD_T_DRP_TRYWAIT);
+               break;
+       case SRC_TRYWAIT:
+               tcpm_set_cc(port, tcpm_rp_cc(port));
+               if (!port->vbus_present && tcpm_port_is_source(port))
+                       tcpm_set_state(port, SRC_ATTACHED, PD_T_CC_DEBOUNCE);
+               else
+                       tcpm_set_state(port, SRC_TRYWAIT_UNATTACHED,
+                                      PD_T_DRP_TRY);
+               break;
+       case SRC_TRYWAIT_UNATTACHED:
+               tcpm_set_state(port, SNK_UNATTACHED, 0);
+               break;
+
+       case SRC_ATTACHED:
+               ret = tcpm_src_attach(port);
+               tcpm_set_state(port, SRC_UNATTACHED,
+                              ret < 0 ? 0 : PD_T_PS_SOURCE_ON);
+               break;
+       case SRC_STARTUP:
+               typec_set_pwr_opmode(port->typec_port, TYPEC_PWR_MODE_USB);
+               port->pwr_opmode = TYPEC_PWR_MODE_USB;
+               port->caps_count = 0;
+               port->message_id = 0;
+               port->explicit_contract = false;
+               tcpm_set_state(port, SRC_SEND_CAPABILITIES, 0);
+               break;
+       case SRC_SEND_CAPABILITIES:
+               port->caps_count++;
+               if (port->caps_count > PD_N_CAPS_COUNT) {
+                       tcpm_set_state(port, SRC_READY, 0);
+                       break;
+               }
+               ret = tcpm_pd_send_source_caps(port);
+               if (ret < 0) {
+                       tcpm_set_state(port, SRC_SEND_CAPABILITIES,
+                                      PD_T_SEND_SOURCE_CAP);
+               } else {
+                       /*
+                        * Per standard, we should clear the reset counter here.
+                        * However, that can result in state machine hang-ups.
+                        * Reset it only in READY state to improve stability.
+                        */
+                       /* port->hard_reset_count = 0; */
+                       port->caps_count = 0;
+                       port->pd_capable = true;
+                       tcpm_set_state_cond(port, hard_reset_state(port),
+                                           PD_T_SEND_SOURCE_CAP);
+               }
+               break;
+       case SRC_NEGOTIATE_CAPABILITIES:
+               ret = tcpm_pd_check_request(port);
+               if (ret < 0) {
+                       tcpm_pd_send_control(port, PD_CTRL_REJECT);
+                       if (!port->explicit_contract) {
+                               tcpm_set_state(port,
+                                              SRC_WAIT_NEW_CAPABILITIES, 0);
+                       } else {
+                               tcpm_set_state(port, SRC_READY, 0);
+                       }
+               } else {
+                       tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
+                       tcpm_set_state(port, SRC_TRANSITION_SUPPLY,
+                                      PD_T_SRC_TRANSITION);
+               }
+               break;
+       case SRC_TRANSITION_SUPPLY:
+               /* XXX: regulator_set_voltage(vbus, ...) */
+               tcpm_pd_send_control(port, PD_CTRL_PS_RDY);
+               port->explicit_contract = true;
+               typec_set_pwr_opmode(port->typec_port, TYPEC_PWR_MODE_PD);
+               port->pwr_opmode = TYPEC_PWR_MODE_PD;
+               tcpm_set_state_cond(port, SRC_READY, 0);
+               break;
+       case SRC_READY:
+#if 1
+               port->hard_reset_count = 0;
+#endif
+               port->try_src_count = 0;
+
+               tcpm_typec_connect(port);
+
+               tcpm_check_send_discover(port);
+               /*
+                * 6.3.5
+                * Sending ping messages is not necessary if
+                * - the source operates at vSafe5V
+                * or
+                * - The system is not operating in PD mode
+                * or
+                * - Both partners are connected using a Type-C connector
+                *   XXX How do we know that ?
+                */
+               if (port->pwr_opmode == TYPEC_PWR_MODE_PD &&
+                   !port->op_vsafe5v) {
+                       tcpm_pd_send_control(port, PD_CTRL_PING);
+                       tcpm_set_state_cond(port, SRC_READY,
+                                           PD_T_SOURCE_ACTIVITY);
+               }
+               break;
+       case SRC_WAIT_NEW_CAPABILITIES:
+               /* Nothing to do... */
+               break;
+
+       /* SNK states */
+       case SNK_UNATTACHED:
+               tcpm_swap_complete(port, -ENOTCONN);
+               tcpm_snk_detach(port);
+               if (tcpm_start_drp_toggling(port)) {
+                       tcpm_set_state(port, DRP_TOGGLING, 0);
+                       break;
+               }
+               tcpm_set_cc(port, TYPEC_CC_RD);
+               if (port->typec_caps.type == TYPEC_PORT_DRP)
+                       tcpm_set_state(port, SRC_UNATTACHED, PD_T_DRP_SRC);
+               break;
+       case SNK_ATTACH_WAIT:
+               if ((port->cc1 == TYPEC_CC_OPEN &&
+                    port->cc2 != TYPEC_CC_OPEN) ||
+                   (port->cc1 != TYPEC_CC_OPEN &&
+                    port->cc2 == TYPEC_CC_OPEN))
+                       tcpm_set_state(port, SNK_DEBOUNCED,
+                                      PD_T_CC_DEBOUNCE);
+               else if (tcpm_port_is_disconnected(port))
+                       tcpm_set_state(port, SNK_UNATTACHED,
+                                      PD_T_PD_DEBOUNCE);
+               break;
+       case SNK_DEBOUNCED:
+               if (tcpm_port_is_disconnected(port))
+                       tcpm_set_state(port, SNK_UNATTACHED,
+                                      PD_T_PD_DEBOUNCE);
+               else if (port->vbus_present)
+                       tcpm_set_state(port,
+                                      tcpm_try_src(port) ? SRC_TRY
+                                                         : SNK_ATTACHED,
+                                      0);
+               else
+                       /* Wait for VBUS, but not forever */
+                       tcpm_set_state(port, SNK_UNATTACHED, PD_T_PS_SOURCE_ON);
+               break;
+
+       case SRC_TRY:
+               port->try_src_count++;
+               tcpm_set_cc(port, tcpm_rp_cc(port));
+               tcpm_set_state(port, SNK_TRYWAIT, PD_T_DRP_TRY);
+               break;
+       case SRC_TRY_DEBOUNCE:
+               tcpm_set_state(port, SRC_ATTACHED, PD_T_PD_DEBOUNCE);
+               break;
+       case SNK_TRYWAIT:
+               tcpm_set_cc(port, TYPEC_CC_RD);
+               tcpm_set_state(port, SNK_TRYWAIT_DEBOUNCE, PD_T_CC_DEBOUNCE);
+               break;
+       case SNK_TRYWAIT_DEBOUNCE:
+               if (port->vbus_present) {
+                       tcpm_set_state(port, SNK_ATTACHED, 0);
+                       break;
+               }
+               if (tcpm_port_is_disconnected(port)) {
+                       tcpm_set_state(port, SNK_UNATTACHED,
+                                      PD_T_PD_DEBOUNCE);
+                       break;
+               }
+               if (tcpm_port_is_source(port))
+                       tcpm_set_state(port, SRC_ATTACHED, 0);
+               /* XXX Are we supposed to stay in this state ? */
+               break;
+       case SNK_TRYWAIT_VBUS:
+               tcpm_set_state(port, SNK_ATTACHED, PD_T_CC_DEBOUNCE);
+               break;
+
+       case SNK_ATTACHED:
+               ret = tcpm_snk_attach(port);
+               if (ret < 0)
+                       tcpm_set_state(port, SNK_UNATTACHED, 0);
+               else
+                       tcpm_set_state(port, SNK_STARTUP, 0);
+               break;
+       case SNK_STARTUP:
+               /* XXX: callback into infrastructure */
+               typec_set_pwr_opmode(port->typec_port, TYPEC_PWR_MODE_USB);
+               port->pwr_opmode = TYPEC_PWR_MODE_USB;
+               port->message_id = 0;
+               port->explicit_contract = false;
+               tcpm_set_state(port, SNK_DISCOVERY, 0);
+               break;
+       case SNK_DISCOVERY:
+               if (port->vbus_present) {
+                       tcpm_set_current_limit(port,
+                                              tcpm_get_current_limit(port),
+                                              5000);
+                       tcpm_set_charge(port, true);
+                       tcpm_set_state(port, SNK_WAIT_CAPABILITIES, 0);
+                       break;
+               }
+               /*
+                * For DRP, timeouts differ. Also, handling is supposed to be
+                * different and much more complex (dead battery detection;
+                * see USB power delivery specification, section 8.3.3.6.1.5.1).
+                */
+               tcpm_set_state(port, hard_reset_state(port),
+                              port->typec_caps.type == TYPEC_PORT_DRP ?
+                                       PD_T_DB_DETECT : PD_T_NO_RESPONSE);
+               break;
+       case SNK_DISCOVERY_DEBOUNCE:
+               tcpm_set_state(port, SNK_DISCOVERY_DEBOUNCE_DONE,
+                              PD_T_CC_DEBOUNCE);
+               break;
+       case SNK_DISCOVERY_DEBOUNCE_DONE:
+               if (!tcpm_port_is_disconnected(port) &&
+                   tcpm_port_is_sink(port) &&
+                   time_is_after_jiffies(port->delayed_runtime)) {
+                       tcpm_set_state(port, SNK_DISCOVERY,
+                                      port->delayed_runtime - jiffies);
+                       break;
+               }
+               tcpm_set_state(port, unattached_state(port), 0);
+               break;
+       case SNK_WAIT_CAPABILITIES:
+               ret = port->tcpc->set_pd_rx(port->tcpc, true);
+               if (ret < 0) {
+                       tcpm_set_state(port, SNK_READY, 0);
+                       break;
+               }
+               /*
+                * If VBUS has never been low, and we time out waiting
+                * for source cap, try a soft reset first, in case we
+                * were already in a stable contract before this boot.
+                * Do this only once.
+                */
+               if (port->vbus_never_low) {
+                       port->vbus_never_low = false;
+                       tcpm_set_state(port, SOFT_RESET_SEND,
+                                      PD_T_SINK_WAIT_CAP);
+               } else {
+                       tcpm_set_state(port, hard_reset_state(port),
+                                      PD_T_SINK_WAIT_CAP);
+               }
+               break;
+       case SNK_NEGOTIATE_CAPABILITIES:
+               port->pd_capable = true;
+               port->hard_reset_count = 0;
+               ret = tcpm_pd_send_request(port);
+               if (ret < 0) {
+                       /* Let the Source send capabilities again. */
+                       tcpm_set_state(port, SNK_WAIT_CAPABILITIES, 0);
+               } else {
+                       tcpm_set_state_cond(port, hard_reset_state(port),
+                                           PD_T_SENDER_RESPONSE);
+               }
+               break;
+       case SNK_TRANSITION_SINK:
+       case SNK_TRANSITION_SINK_VBUS:
+               tcpm_set_state(port, hard_reset_state(port),
+                              PD_T_PS_TRANSITION);
+               break;
+       case SNK_READY:
+               port->try_snk_count = 0;
+               port->explicit_contract = true;
+               typec_set_pwr_opmode(port->typec_port, TYPEC_PWR_MODE_PD);
+               port->pwr_opmode = TYPEC_PWR_MODE_PD;
+
+               tcpm_typec_connect(port);
+
+               tcpm_check_send_discover(port);
+               break;
+
+       /* Accessory states */
+       case ACC_UNATTACHED:
+               tcpm_acc_detach(port);
+               tcpm_set_state(port, SRC_UNATTACHED, 0);
+               break;
+       case DEBUG_ACC_ATTACHED:
+       case AUDIO_ACC_ATTACHED:
+               ret = tcpm_acc_attach(port);
+               if (ret < 0)
+                       tcpm_set_state(port, ACC_UNATTACHED, 0);
+               break;
+       case AUDIO_ACC_DEBOUNCE:
+               tcpm_set_state(port, ACC_UNATTACHED, PD_T_CC_DEBOUNCE);
+               break;
+
+       /* Hard_Reset states */
+       case HARD_RESET_SEND:
+               tcpm_pd_transmit(port, TCPC_TX_HARD_RESET, NULL);
+               tcpm_set_state(port, HARD_RESET_START, 0);
+               break;
+       case HARD_RESET_START:
+               port->hard_reset_count++;
+               port->tcpc->set_pd_rx(port->tcpc, false);
+               tcpm_unregister_altmodes(port);
+               port->send_discover = true;
+               if (port->pwr_role == TYPEC_SOURCE)
+                       tcpm_set_state(port, SRC_HARD_RESET_VBUS_OFF,
+                                      PD_T_PS_HARD_RESET);
+               else
+                       tcpm_set_state(port, SNK_HARD_RESET_SINK_OFF, 0);
+               break;
+       case SRC_HARD_RESET_VBUS_OFF:
+               tcpm_set_vconn(port, true);
+               tcpm_set_vbus(port, false);
+               tcpm_set_roles(port, false, TYPEC_SOURCE, TYPEC_HOST);
+               tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER);
+               break;
+       case SRC_HARD_RESET_VBUS_ON:
+               tcpm_set_vbus(port, true);
+               port->tcpc->set_pd_rx(port->tcpc, true);
+               tcpm_set_attached_state(port, true);
+               tcpm_set_state(port, SRC_UNATTACHED, PD_T_PS_SOURCE_ON);
+               break;
+       case SNK_HARD_RESET_SINK_OFF:
+               tcpm_set_vconn(port, false);
+               tcpm_set_charge(port, false);
+               tcpm_set_roles(port, false, TYPEC_SINK, TYPEC_DEVICE);
+               /*
+                * VBUS may or may not toggle, depending on the adapter.
+                * If it doesn't toggle, transition to SNK_HARD_RESET_SINK_ON
+                * directly after timeout.
+                */
+               tcpm_set_state(port, SNK_HARD_RESET_SINK_ON, PD_T_SAFE_0V);
+               break;
+       case SNK_HARD_RESET_WAIT_VBUS:
+               /* Assume we're disconnected if VBUS doesn't come back. */
+               tcpm_set_state(port, SNK_UNATTACHED,
+                              PD_T_SRC_RECOVER_MAX + PD_T_SRC_TURN_ON);
+               break;
+       case SNK_HARD_RESET_SINK_ON:
+               /* Note: There is no guarantee that VBUS is on in this state */
+               /*
+                * XXX:
+                * The specification suggests that dual mode ports in sink
+                * mode should transition to state PE_SRC_Transition_to_default.
+                * See USB power delivery specification chapter 8.3.3.6.1.3.
+                * This would mean to to
+                * - turn off VCONN, reset power supply
+                * - request hardware reset
+                * - turn on VCONN
+                * - Transition to state PE_Src_Startup
+                * SNK only ports shall transition to state Snk_Startup
+                * (see chapter 8.3.3.3.8).
+                * Similar, dual-mode ports in source mode should transition
+                * to PE_SNK_Transition_to_default.
+                */
+               tcpm_set_attached_state(port, true);
+               tcpm_set_state(port, SNK_STARTUP, 0);
+               break;
+
+       /* Soft_Reset states */
+       case SOFT_RESET:
+               port->message_id = 0;
+               tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
+               if (port->pwr_role == TYPEC_SOURCE)
+                       tcpm_set_state(port, SRC_SEND_CAPABILITIES, 0);
+               else
+                       tcpm_set_state(port, SNK_WAIT_CAPABILITIES, 0);
+               break;
+       case SOFT_RESET_SEND:
+               port->message_id = 0;
+               if (tcpm_pd_send_control(port, PD_CTRL_SOFT_RESET))
+                       tcpm_set_state_cond(port, hard_reset_state(port), 0);
+               else
+                       tcpm_set_state_cond(port, hard_reset_state(port),
+                                           PD_T_SENDER_RESPONSE);
+               break;
+
+       /* DR_Swap states */
+       case DR_SWAP_SEND:
+               tcpm_pd_send_control(port, PD_CTRL_DR_SWAP);
+               tcpm_set_state_cond(port, DR_SWAP_SEND_TIMEOUT,
+                                   PD_T_SENDER_RESPONSE);
+               break;
+       case DR_SWAP_ACCEPT:
+               tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
+               tcpm_set_state_cond(port, DR_SWAP_CHANGE_DR, 0);
+               break;
+       case DR_SWAP_SEND_TIMEOUT:
+               tcpm_swap_complete(port, -ETIMEDOUT);
+               tcpm_set_state(port, ready_state(port), 0);
+               break;
+       case DR_SWAP_CHANGE_DR:
+               if (port->data_role == TYPEC_HOST) {
+                       tcpm_unregister_altmodes(port);
+                       tcpm_set_roles(port, true, port->pwr_role,
+                                      TYPEC_DEVICE);
+               } else {
+                       tcpm_set_roles(port, true, port->pwr_role,
+                                      TYPEC_HOST);
+                       port->send_discover = true;
+               }
+               tcpm_swap_complete(port, 0);
+               tcpm_set_state(port, ready_state(port), 0);
+               break;
+
+       /* PR_Swap states */
+       case PR_SWAP_ACCEPT:
+               tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
+               tcpm_set_state(port, PR_SWAP_START, 0);
+               break;
+       case PR_SWAP_SEND:
+               tcpm_pd_send_control(port, PD_CTRL_PR_SWAP);
+               tcpm_set_state_cond(port, PR_SWAP_SEND_TIMEOUT,
+                                   PD_T_SENDER_RESPONSE);
+               break;
+       case PR_SWAP_SEND_TIMEOUT:
+               tcpm_swap_complete(port, -ETIMEDOUT);
+               tcpm_set_state(port, ready_state(port), 0);
+               break;
+       case PR_SWAP_START:
+               if (port->pwr_role == TYPEC_SOURCE)
+                       tcpm_set_state(port, PR_SWAP_SRC_SNK_TRANSITION_OFF,
+                                      PD_T_SRC_TRANSITION);
+               else
+                       tcpm_set_state(port, PR_SWAP_SNK_SRC_SINK_OFF, 0);
+               break;
+       case PR_SWAP_SRC_SNK_TRANSITION_OFF:
+               tcpm_set_vbus(port, false);
+               port->explicit_contract = false;
+               tcpm_set_state(port, PR_SWAP_SRC_SNK_SOURCE_OFF,
+                              PD_T_PS_SOURCE_OFF);
+               break;
+       case PR_SWAP_SRC_SNK_SOURCE_OFF:
+               tcpm_set_cc(port, TYPEC_CC_RD);
+               if (tcpm_pd_send_control(port, PD_CTRL_PS_RDY)) {
+                       tcpm_set_state(port, ERROR_RECOVERY, 0);
+                       break;
+               }
+               tcpm_set_state_cond(port, SNK_UNATTACHED, PD_T_PS_SOURCE_ON);
+               break;
+       case PR_SWAP_SRC_SNK_SINK_ON:
+               tcpm_set_pwr_role(port, TYPEC_SINK);
+               tcpm_swap_complete(port, 0);
+               tcpm_set_state(port, SNK_STARTUP, 0);
+               break;
+       case PR_SWAP_SNK_SRC_SINK_OFF:
+               tcpm_set_charge(port, false);
+               tcpm_set_state(port, hard_reset_state(port),
+                              PD_T_PS_SOURCE_OFF);
+               break;
+       case PR_SWAP_SNK_SRC_SOURCE_ON:
+               tcpm_set_cc(port, tcpm_rp_cc(port));
+               tcpm_set_vbus(port, true);
+               tcpm_pd_send_control(port, PD_CTRL_PS_RDY);
+               tcpm_set_pwr_role(port, TYPEC_SOURCE);
+               tcpm_swap_complete(port, 0);
+               tcpm_set_state(port, SRC_STARTUP, 0);
+               break;
+
+       case VCONN_SWAP_ACCEPT:
+               tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
+               tcpm_set_state(port, VCONN_SWAP_START, 0);
+               break;
+       case VCONN_SWAP_SEND:
+               tcpm_pd_send_control(port, PD_CTRL_VCONN_SWAP);
+               tcpm_set_state(port, VCONN_SWAP_SEND_TIMEOUT,
+                              PD_T_SENDER_RESPONSE);
+               break;
+       case VCONN_SWAP_SEND_TIMEOUT:
+               tcpm_swap_complete(port, -ETIMEDOUT);
+               tcpm_set_state(port, ready_state(port), 0);
+               break;
+       case VCONN_SWAP_START:
+               if (port->vconn_role == TYPEC_SOURCE)
+                       tcpm_set_state(port, VCONN_SWAP_WAIT_FOR_VCONN, 0);
+               else
+                       tcpm_set_state(port, VCONN_SWAP_TURN_ON_VCONN, 0);
+               break;
+       case VCONN_SWAP_WAIT_FOR_VCONN:
+               tcpm_set_state(port, hard_reset_state(port),
+                              PD_T_VCONN_SOURCE_ON);
+               break;
+       case VCONN_SWAP_TURN_ON_VCONN:
+               tcpm_set_vconn(port, true);
+               tcpm_pd_send_control(port, PD_CTRL_PS_RDY);
+               tcpm_swap_complete(port, 0);
+               tcpm_set_state(port, ready_state(port), 0);
+               break;
+       case VCONN_SWAP_TURN_OFF_VCONN:
+               tcpm_set_vconn(port, false);
+               tcpm_swap_complete(port, 0);
+               tcpm_set_state(port, ready_state(port), 0);
+               break;
+
+       case DR_SWAP_CANCEL:
+       case PR_SWAP_CANCEL:
+       case VCONN_SWAP_CANCEL:
+               tcpm_swap_complete(port, port->swap_status);
+               if (port->pwr_role == TYPEC_SOURCE)
+                       tcpm_set_state(port, SRC_READY, 0);
+               else
+                       tcpm_set_state(port, SNK_READY, 0);
+               break;
+
+       case BIST_RX:
+               switch (BDO_MODE_MASK(port->bist_request)) {
+               case BDO_MODE_CARRIER2:
+                       tcpm_pd_transmit(port, TCPC_TX_BIST_MODE_2, NULL);
+                       break;
+               default:
+                       break;
+               }
+               /* Always switch to unattached state */
+               tcpm_set_state(port, unattached_state(port), 0);
+               break;
+       case ERROR_RECOVERY:
+               tcpm_swap_complete(port, -EPROTO);
+               tcpm_reset_port(port);
+
+               tcpm_set_cc(port, TYPEC_CC_OPEN);
+               tcpm_set_state(port, ERROR_RECOVERY_WAIT_OFF,
+                              PD_T_ERROR_RECOVERY);
+               break;
+       case ERROR_RECOVERY_WAIT_OFF:
+               tcpm_set_state(port,
+                              tcpm_default_state(port),
+                              port->vbus_present ? PD_T_PS_SOURCE_OFF : 0);
+               break;
+       default:
+               WARN(1, "Unexpected port state %d\n", port->state);
+               break;
+       }
+}
+
+static void tcpm_state_machine_work(struct work_struct *work)
+{
+       struct tcpm_port *port = container_of(work, struct tcpm_port,
+                                             state_machine.work);
+       enum tcpm_state prev_state;
+
+       mutex_lock(&port->lock);
+       port->state_machine_running = true;
+
+       if (port->queued_message && tcpm_send_queued_message(port))
+               goto done;
+
+       /* If we were queued due to a delayed state change, update it now */
+       if (port->delayed_state) {
+               tcpm_log(port, "state change %s -> %s [delayed %ld ms]",
+                        tcpm_states[port->state],
+                        tcpm_states[port->delayed_state], port->delay_ms);
+               port->prev_state = port->state;
+               port->state = port->delayed_state;
+               port->delayed_state = INVALID_STATE;
+       }
+
+       /*
+        * Continue running as long as we have (non-delayed) state changes
+        * to make.
+        */
+       do {
+               prev_state = port->state;
+               run_state_machine(port);
+               if (port->queued_message)
+                       tcpm_send_queued_message(port);
+       } while (port->state != prev_state && !port->delayed_state);
+
+done:
+       port->state_machine_running = false;
+       mutex_unlock(&port->lock);
+}
+
+static void _tcpm_cc_change(struct tcpm_port *port, enum typec_cc_status cc1,
+                           enum typec_cc_status cc2)
+{
+       enum typec_cc_status old_cc1, old_cc2;
+       enum tcpm_state new_state;
+
+       old_cc1 = port->cc1;
+       old_cc2 = port->cc2;
+       port->cc1 = cc1;
+       port->cc2 = cc2;
+
+       tcpm_log_force(port,
+                      "CC1: %u -> %u, CC2: %u -> %u [state %s, polarity %d, %s]",
+                      old_cc1, cc1, old_cc2, cc2, tcpm_states[port->state],
+                      port->polarity,
+                      tcpm_port_is_disconnected(port) ? "disconnected"
+                                                      : "connected");
+
+       switch (port->state) {
+       case DRP_TOGGLING:
+               if (tcpm_port_is_debug(port) || tcpm_port_is_audio(port) ||
+                   tcpm_port_is_source(port))
+                       tcpm_set_state(port, SRC_ATTACH_WAIT, 0);
+               else if (tcpm_port_is_sink(port))
+                       tcpm_set_state(port, SNK_ATTACH_WAIT, 0);
+               break;
+       case SRC_UNATTACHED:
+       case ACC_UNATTACHED:
+               if (tcpm_port_is_debug(port) || tcpm_port_is_audio(port) ||
+                   tcpm_port_is_source(port))
+                       tcpm_set_state(port, SRC_ATTACH_WAIT, 0);
+               break;
+       case SRC_ATTACH_WAIT:
+               if (tcpm_port_is_disconnected(port) ||
+                   tcpm_port_is_audio_detached(port))
+                       tcpm_set_state(port, SRC_UNATTACHED, 0);
+               else if (cc1 != old_cc1 || cc2 != old_cc2)
+                       tcpm_set_state(port, SRC_ATTACH_WAIT, 0);
+               break;
+       case SRC_ATTACHED:
+               if (tcpm_port_is_disconnected(port))
+                       tcpm_set_state(port, SRC_UNATTACHED, 0);
+               break;
+
+       case SNK_UNATTACHED:
+               if (tcpm_port_is_sink(port))
+                       tcpm_set_state(port, SNK_ATTACH_WAIT, 0);
+               break;
+       case SNK_ATTACH_WAIT:
+               if ((port->cc1 == TYPEC_CC_OPEN &&
+                    port->cc2 != TYPEC_CC_OPEN) ||
+                   (port->cc1 != TYPEC_CC_OPEN &&
+                    port->cc2 == TYPEC_CC_OPEN))
+                       new_state = SNK_DEBOUNCED;
+               else if (tcpm_port_is_disconnected(port))
+                       new_state = SNK_UNATTACHED;
+               else
+                       break;
+               if (new_state != port->delayed_state)
+                       tcpm_set_state(port, SNK_ATTACH_WAIT, 0);
+               break;
+       case SNK_DEBOUNCED:
+               if (tcpm_port_is_disconnected(port))
+                       new_state = SNK_UNATTACHED;
+               else if (port->vbus_present)
+                       new_state = tcpm_try_src(port) ? SRC_TRY : SNK_ATTACHED;
+               else
+                       new_state = SNK_UNATTACHED;
+               if (new_state != port->delayed_state)
+                       tcpm_set_state(port, SNK_DEBOUNCED, 0);
+               break;
+       case SNK_READY:
+               if (tcpm_port_is_disconnected(port))
+                       tcpm_set_state(port, unattached_state(port), 0);
+               else if (!port->pd_capable &&
+                        (cc1 != old_cc1 || cc2 != old_cc2))
+                       tcpm_set_current_limit(port,
+                                              tcpm_get_current_limit(port),
+                                              5000);
+               break;
+
+       case AUDIO_ACC_ATTACHED:
+               if (cc1 == TYPEC_CC_OPEN || cc2 == TYPEC_CC_OPEN)
+                       tcpm_set_state(port, AUDIO_ACC_DEBOUNCE, 0);
+               break;
+       case AUDIO_ACC_DEBOUNCE:
+               if (tcpm_port_is_audio(port))
+                       tcpm_set_state(port, AUDIO_ACC_ATTACHED, 0);
+               break;
+
+       case DEBUG_ACC_ATTACHED:
+               if (cc1 == TYPEC_CC_OPEN || cc2 == TYPEC_CC_OPEN)
+                       tcpm_set_state(port, ACC_UNATTACHED, 0);
+               break;
+
+       case SNK_TRY:
+               /* Do nothing, waiting for timeout */
+               break;
+
+       case SNK_DISCOVERY:
+               /* CC line is unstable, wait for debounce */
+               if (tcpm_port_is_disconnected(port))
+                       tcpm_set_state(port, SNK_DISCOVERY_DEBOUNCE, 0);
+               break;
+       case SNK_DISCOVERY_DEBOUNCE:
+               break;
+
+       case SRC_TRYWAIT:
+               /* Hand over to state machine if needed */
+               if (!port->vbus_present && tcpm_port_is_source(port))
+                       new_state = SRC_ATTACHED;
+               else
+                       new_state = SRC_TRYWAIT_UNATTACHED;
+
+               if (new_state != port->delayed_state)
+                       tcpm_set_state(port, SRC_TRYWAIT, 0);
+               break;
+       case SNK_TRY_WAIT:
+               if (port->vbus_present && tcpm_port_is_sink(port)) {
+                       tcpm_set_state(port, SNK_ATTACHED, 0);
+                       break;
+               }
+               if (!tcpm_port_is_sink(port))
+                       new_state = SRC_TRYWAIT;
+               else
+                       new_state = SRC_TRYWAIT_UNATTACHED;
+
+               if (new_state != port->delayed_state)
+                       tcpm_set_state(port, SNK_TRY_WAIT, 0);
+               break;
+
+       case SRC_TRY:
+               tcpm_set_state(port, SRC_TRY_DEBOUNCE, 0);
+               break;
+       case SRC_TRY_DEBOUNCE:
+               tcpm_set_state(port, SRC_TRY, 0);
+               break;
+       case SNK_TRYWAIT_DEBOUNCE:
+               if (port->vbus_present) {
+                       tcpm_set_state(port, SNK_ATTACHED, 0);
+                       break;
+               }
+               if (tcpm_port_is_source(port)) {
+                       tcpm_set_state(port, SRC_ATTACHED, 0);
+                       break;
+               }
+               if (tcpm_port_is_disconnected(port) &&
+                   port->delayed_state != SNK_UNATTACHED)
+                       tcpm_set_state(port, SNK_TRYWAIT_DEBOUNCE, 0);
+               break;
+
+       case PR_SWAP_SNK_SRC_SINK_OFF:
+       case PR_SWAP_SRC_SNK_TRANSITION_OFF:
+       case PR_SWAP_SRC_SNK_SOURCE_OFF:
+               /*
+                * CC state change is expected here; we just turned off power.
+                * Ignore it.
+                */
+               break;
+
+       default:
+               if (tcpm_port_is_disconnected(port))
+                       tcpm_set_state(port, unattached_state(port), 0);
+               break;
+       }
+}
+
+static void _tcpm_pd_vbus_on(struct tcpm_port *port)
+{
+       enum tcpm_state new_state;
+
+       tcpm_log_force(port, "VBUS on");
+       port->vbus_present = true;
+       switch (port->state) {
+       case SNK_TRANSITION_SINK_VBUS:
+               tcpm_set_state(port, SNK_READY, 0);
+               break;
+       case SNK_DISCOVERY:
+               tcpm_set_state(port, SNK_DISCOVERY, 0);
+               break;
+
+       case SNK_DEBOUNCED:
+               tcpm_set_state(port, tcpm_try_src(port) ? SRC_TRY
+                                                       : SNK_ATTACHED,
+                                      0);
+               break;
+       case SNK_HARD_RESET_WAIT_VBUS:
+               tcpm_set_state(port, SNK_HARD_RESET_SINK_ON, 0);
+               break;
+       case SRC_ATTACHED:
+               tcpm_set_state(port, SRC_STARTUP, 0);
+               break;
+       case SRC_HARD_RESET_VBUS_ON:
+               tcpm_set_state(port, SRC_STARTUP, 0);
+               break;
+
+       case SNK_TRY:
+               /* Do nothing, waiting for timeout */
+               break;
+       case SRC_TRYWAIT:
+               /* Hand over to state machine if needed */
+               if (port->delayed_state != SRC_TRYWAIT_UNATTACHED)
+                       tcpm_set_state(port, SRC_TRYWAIT, 0);
+               break;
+       case SNK_TRY_WAIT:
+               if (tcpm_port_is_sink(port)) {
+                       tcpm_set_state(port, SNK_ATTACHED, 0);
+                       break;
+               }
+               if (!tcpm_port_is_sink(port))
+                       new_state = SRC_TRYWAIT;
+               else
+                       new_state = SRC_TRYWAIT_UNATTACHED;
+
+               if (new_state != port->delayed_state)
+                       tcpm_set_state(port, SNK_TRY_WAIT, 0);
+               break;
+       case SNK_TRYWAIT:
+               tcpm_set_state(port, SNK_TRYWAIT_VBUS, 0);
+               break;
+
+       default:
+               break;
+       }
+}
+
+static void _tcpm_pd_vbus_off(struct tcpm_port *port)
+{
+       enum tcpm_state new_state;
+
+       tcpm_log_force(port, "VBUS off");
+       port->vbus_present = false;
+       port->vbus_never_low = false;
+       switch (port->state) {
+       case SNK_HARD_RESET_SINK_OFF:
+               tcpm_set_state(port, SNK_HARD_RESET_WAIT_VBUS, 0);
+               break;
+       case SRC_HARD_RESET_VBUS_OFF:
+               tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, 0);
+               break;
+       case HARD_RESET_SEND:
+               break;
+
+       case SNK_TRY:
+               /* Do nothing, waiting for timeout */
+               break;
+       case SRC_TRYWAIT:
+               /* Hand over to state machine if needed */
+               if (tcpm_port_is_source(port))
+                       new_state = SRC_ATTACHED;
+               else
+                       new_state = SRC_TRYWAIT_UNATTACHED;
+               if (new_state != port->delayed_state)
+                       tcpm_set_state(port, SRC_TRYWAIT, 0);
+               break;
+       case SNK_TRY_WAIT:
+               if (!tcpm_port_is_sink(port))
+                       new_state = SRC_TRYWAIT;
+               else
+                       new_state = SRC_TRYWAIT_UNATTACHED;
+
+               if (new_state != port->delayed_state)
+                       tcpm_set_state(port, SNK_TRY_WAIT, 0);
+               break;
+       case SNK_TRYWAIT_VBUS:
+               tcpm_set_state(port, SNK_TRYWAIT, 0);
+               break;
+
+       case SNK_ATTACH_WAIT:
+               tcpm_set_state(port, SNK_UNATTACHED, 0);
+               break;
+
+       case SNK_NEGOTIATE_CAPABILITIES:
+               break;
+
+       case PR_SWAP_SRC_SNK_TRANSITION_OFF:
+               tcpm_set_state(port, PR_SWAP_SRC_SNK_SOURCE_OFF, 0);
+               break;
+
+       case PR_SWAP_SNK_SRC_SINK_OFF:
+               /* Do nothing, expected */
+               break;
+
+       case ERROR_RECOVERY_WAIT_OFF:
+               tcpm_set_state(port,
+                              port->pwr_role == TYPEC_SOURCE ?
+                                       SRC_UNATTACHED : SNK_UNATTACHED,
+                              0);
+               break;
+
+       default:
+               if (port->pwr_role == TYPEC_SINK &&
+                   port->attached)
+                       tcpm_set_state(port, SNK_UNATTACHED, 0);
+               break;
+       }
+}
+
+static void _tcpm_pd_hard_reset(struct tcpm_port *port)
+{
+       tcpm_log_force(port, "Received hard reset");
+       /*
+        * If we keep receiving hard reset requests, executing the hard reset
+        * must have failed. Revert to error recovery if that happens.
+        */
+       tcpm_set_state(port,
+                      port->hard_reset_count < PD_N_HARD_RESET_COUNT ?
+                               HARD_RESET_START : ERROR_RECOVERY,
+                      0);
+}
+
+static void tcpm_pd_event_handler(struct work_struct *work)
+{
+       struct tcpm_port *port = container_of(work, struct tcpm_port,
+                                             event_work);
+       u32 events;
+
+       mutex_lock(&port->lock);
+
+       spin_lock(&port->pd_event_lock);
+       while (port->pd_events) {
+               events = port->pd_events;
+               port->pd_events = 0;
+               spin_unlock(&port->pd_event_lock);
+               if (events & TCPM_RESET_EVENT)
+                       _tcpm_pd_hard_reset(port);
+               if (events & TCPM_VBUS_EVENT) {
+                       bool vbus;
+
+                       vbus = port->tcpc->get_vbus(port->tcpc);
+                       if (vbus)
+                               _tcpm_pd_vbus_on(port);
+                       else
+                               _tcpm_pd_vbus_off(port);
+               }
+               if (events & TCPM_CC_EVENT) {
+                       enum typec_cc_status cc1, cc2;
+
+                       if (port->tcpc->get_cc(port->tcpc, &cc1, &cc2) == 0)
+                               _tcpm_cc_change(port, cc1, cc2);
+               }
+               spin_lock(&port->pd_event_lock);
+       }
+       spin_unlock(&port->pd_event_lock);
+       mutex_unlock(&port->lock);
+}
+
+void tcpm_cc_change(struct tcpm_port *port)
+{
+       spin_lock(&port->pd_event_lock);
+       port->pd_events |= TCPM_CC_EVENT;
+       spin_unlock(&port->pd_event_lock);
+       queue_work(port->wq, &port->event_work);
+}
+EXPORT_SYMBOL_GPL(tcpm_cc_change);
+
+void tcpm_vbus_change(struct tcpm_port *port)
+{
+       spin_lock(&port->pd_event_lock);
+       port->pd_events |= TCPM_VBUS_EVENT;
+       spin_unlock(&port->pd_event_lock);
+       queue_work(port->wq, &port->event_work);
+}
+EXPORT_SYMBOL_GPL(tcpm_vbus_change);
+
+void tcpm_pd_hard_reset(struct tcpm_port *port)
+{
+       spin_lock(&port->pd_event_lock);
+       port->pd_events = TCPM_RESET_EVENT;
+       spin_unlock(&port->pd_event_lock);
+       queue_work(port->wq, &port->event_work);
+}
+EXPORT_SYMBOL_GPL(tcpm_pd_hard_reset);
+
+static int tcpm_dr_set(const struct typec_capability *cap,
+                      enum typec_data_role data)
+{
+       struct tcpm_port *port = typec_cap_to_tcpm(cap);
+       int ret;
+
+       mutex_lock(&port->swap_lock);
+       mutex_lock(&port->lock);
+
+       if (port->typec_caps.type != TYPEC_PORT_DRP || !port->pd_capable) {
+               ret = -EINVAL;
+               goto port_unlock;
+       }
+       if (port->state != SRC_READY && port->state != SNK_READY) {
+               ret = -EAGAIN;
+               goto port_unlock;
+       }
+
+       if (port->data_role == data) {
+               ret = 0;
+               goto port_unlock;
+       }
+
+       /*
+        * XXX
+        * 6.3.9: If an alternate mode is active, a request to swap
+        * alternate modes shall trigger a port reset.
+        * Reject data role swap request in this case.
+        */
+
+       port->swap_status = 0;
+       port->swap_pending = true;
+       reinit_completion(&port->swap_complete);
+       tcpm_set_state(port, DR_SWAP_SEND, 0);
+       mutex_unlock(&port->lock);
+
+       wait_for_completion(&port->swap_complete);
+
+       ret = port->swap_status;
+       goto swap_unlock;
+
+port_unlock:
+       mutex_unlock(&port->lock);
+swap_unlock:
+       mutex_unlock(&port->swap_lock);
+       return ret;
+}
+
+static int tcpm_pr_set(const struct typec_capability *cap,
+                      enum typec_role role)
+{
+       struct tcpm_port *port = typec_cap_to_tcpm(cap);
+       int ret;
+
+       mutex_lock(&port->swap_lock);
+       mutex_lock(&port->lock);
+
+       if (port->typec_caps.type != TYPEC_PORT_DRP) {
+               ret = -EINVAL;
+               goto port_unlock;
+       }
+       if (port->state != SRC_READY && port->state != SNK_READY) {
+               ret = -EAGAIN;
+               goto port_unlock;
+       }
+
+       if (role == port->pwr_role) {
+               ret = 0;
+               goto port_unlock;
+       }
+
+       if (!port->pd_capable) {
+               /*
+                * If the partner is not PD capable, reset the port to
+                * trigger a role change. This can only work if a preferred
+                * role is configured, and if it matches the requested role.
+                */
+               if (port->try_role == TYPEC_NO_PREFERRED_ROLE ||
+                   port->try_role == port->pwr_role) {
+                       ret = -EINVAL;
+                       goto port_unlock;
+               }
+               tcpm_set_state(port, HARD_RESET_SEND, 0);
+               ret = 0;
+               goto port_unlock;
+       }
+
+       port->swap_status = 0;
+       port->swap_pending = true;
+       reinit_completion(&port->swap_complete);
+       tcpm_set_state(port, PR_SWAP_SEND, 0);
+       mutex_unlock(&port->lock);
+
+       wait_for_completion(&port->swap_complete);
+
+       ret = port->swap_status;
+       goto swap_unlock;
+
+port_unlock:
+       mutex_unlock(&port->lock);
+swap_unlock:
+       mutex_unlock(&port->swap_lock);
+       return ret;
+}
+
+static int tcpm_vconn_set(const struct typec_capability *cap,
+                         enum typec_role role)
+{
+       struct tcpm_port *port = typec_cap_to_tcpm(cap);
+       int ret;
+
+       mutex_lock(&port->swap_lock);
+       mutex_lock(&port->lock);
+
+       if (port->state != SRC_READY && port->state != SNK_READY) {
+               ret = -EAGAIN;
+               goto port_unlock;
+       }
+
+       if (role == port->vconn_role) {
+               ret = 0;
+               goto port_unlock;
+       }
+
+       port->swap_status = 0;
+       port->swap_pending = true;
+       reinit_completion(&port->swap_complete);
+       tcpm_set_state(port, VCONN_SWAP_SEND, 0);
+       mutex_unlock(&port->lock);
+
+       wait_for_completion(&port->swap_complete);
+
+       ret = port->swap_status;
+       goto swap_unlock;
+
+port_unlock:
+       mutex_unlock(&port->lock);
+swap_unlock:
+       mutex_unlock(&port->swap_lock);
+       return ret;
+}
+
+static int tcpm_try_role(const struct typec_capability *cap, int role)
+{
+       struct tcpm_port *port = typec_cap_to_tcpm(cap);
+       struct tcpc_dev *tcpc = port->tcpc;
+       int ret = 0;
+
+       mutex_lock(&port->lock);
+       if (tcpc->try_role)
+               ret = tcpc->try_role(tcpc, role);
+       if (!ret && !tcpc->config->try_role_hw)
+               port->try_role = role;
+       port->try_src_count = 0;
+       port->try_snk_count = 0;
+       mutex_unlock(&port->lock);
+
+       return ret;
+}
+
+static void tcpm_init(struct tcpm_port *port)
+{
+       enum typec_cc_status cc1, cc2;
+
+       port->tcpc->init(port->tcpc);
+
+       tcpm_reset_port(port);
+
+       /*
+        * XXX
+        * Should possibly wait for VBUS to settle if it was enabled locally
+        * since tcpm_reset_port() will disable VBUS.
+        */
+       port->vbus_present = port->tcpc->get_vbus(port->tcpc);
+       if (port->vbus_present)
+               port->vbus_never_low = true;
+
+       tcpm_set_state(port, tcpm_default_state(port), 0);
+
+       if (port->tcpc->get_cc(port->tcpc, &cc1, &cc2) == 0)
+               _tcpm_cc_change(port, cc1, cc2);
+
+       /*
+        * Some adapters need a clean slate at startup, and won't recover
+        * otherwise. So do not try to be fancy and force a clean disconnect.
+        */
+       tcpm_set_state(port, ERROR_RECOVERY, 0);
+}
+
+void tcpm_tcpc_reset(struct tcpm_port *port)
+{
+       mutex_lock(&port->lock);
+       /* XXX: Maintain PD connection if possible? */
+       tcpm_init(port);
+       mutex_unlock(&port->lock);
+}
+EXPORT_SYMBOL_GPL(tcpm_tcpc_reset);
+
+static int tcpm_copy_pdos(u32 *dest_pdo, const u32 *src_pdo,
+                         unsigned int nr_pdo)
+{
+       unsigned int i;
+
+       if (nr_pdo > PDO_MAX_OBJECTS)
+               nr_pdo = PDO_MAX_OBJECTS;
+
+       for (i = 0; i < nr_pdo; i++)
+               dest_pdo[i] = src_pdo[i];
+
+       return nr_pdo;
+}
+
+void tcpm_update_source_capabilities(struct tcpm_port *port, const u32 *pdo,
+                                    unsigned int nr_pdo)
+{
+       mutex_lock(&port->lock);
+       port->nr_src_pdo = tcpm_copy_pdos(port->src_pdo, pdo, nr_pdo);
+       switch (port->state) {
+       case SRC_UNATTACHED:
+       case SRC_ATTACH_WAIT:
+       case SRC_TRYWAIT:
+               tcpm_set_cc(port, tcpm_rp_cc(port));
+               break;
+       case SRC_SEND_CAPABILITIES:
+       case SRC_NEGOTIATE_CAPABILITIES:
+       case SRC_READY:
+       case SRC_WAIT_NEW_CAPABILITIES:
+               tcpm_set_cc(port, tcpm_rp_cc(port));
+               tcpm_set_state(port, SRC_SEND_CAPABILITIES, 0);
+               break;
+       default:
+               break;
+       }
+       mutex_unlock(&port->lock);
+}
+EXPORT_SYMBOL_GPL(tcpm_update_source_capabilities);
+
+void tcpm_update_sink_capabilities(struct tcpm_port *port, const u32 *pdo,
+                                  unsigned int nr_pdo,
+                                  unsigned int max_snk_mv,
+                                  unsigned int max_snk_ma,
+                                  unsigned int max_snk_mw,
+                                  unsigned int operating_snk_mw)
+{
+       mutex_lock(&port->lock);
+       port->nr_snk_pdo = tcpm_copy_pdos(port->snk_pdo, pdo, nr_pdo);
+       port->max_snk_mv = max_snk_mv;
+       port->max_snk_ma = max_snk_ma;
+       port->max_snk_mw = max_snk_mw;
+       port->operating_snk_mw = operating_snk_mw;
+
+       switch (port->state) {
+       case SNK_NEGOTIATE_CAPABILITIES:
+       case SNK_READY:
+       case SNK_TRANSITION_SINK:
+       case SNK_TRANSITION_SINK_VBUS:
+               tcpm_set_state(port, SNK_NEGOTIATE_CAPABILITIES, 0);
+               break;
+       default:
+               break;
+       }
+       mutex_unlock(&port->lock);
+}
+EXPORT_SYMBOL_GPL(tcpm_update_sink_capabilities);
+
+struct tcpm_port *tcpm_register_port(struct device *dev, struct tcpc_dev *tcpc)
+{
+       struct tcpm_port *port;
+       int i, err;
+
+       if (!dev || !tcpc || !tcpc->config ||
+           !tcpc->get_vbus || !tcpc->set_cc || !tcpc->get_cc ||
+           !tcpc->set_polarity || !tcpc->set_vconn || !tcpc->set_vbus ||
+           !tcpc->set_pd_rx || !tcpc->set_roles || !tcpc->pd_transmit)
+               return ERR_PTR(-EINVAL);
+
+       port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
+       if (!port)
+               return ERR_PTR(-ENOMEM);
+
+       port->dev = dev;
+       port->tcpc = tcpc;
+
+       mutex_init(&port->lock);
+       mutex_init(&port->swap_lock);
+
+       port->wq = create_singlethread_workqueue(dev_name(dev));
+       if (!port->wq)
+               return ERR_PTR(-ENOMEM);
+       INIT_DELAYED_WORK(&port->state_machine, tcpm_state_machine_work);
+       INIT_DELAYED_WORK(&port->vdm_state_machine, vdm_state_machine_work);
+       INIT_WORK(&port->event_work, tcpm_pd_event_handler);
+
+       spin_lock_init(&port->pd_event_lock);
+
+       init_completion(&port->tx_complete);
+       init_completion(&port->swap_complete);
+
+       port->nr_src_pdo = tcpm_copy_pdos(port->src_pdo, tcpc->config->src_pdo,
+                                         tcpc->config->nr_src_pdo);
+       port->nr_snk_pdo = tcpm_copy_pdos(port->snk_pdo, tcpc->config->snk_pdo,
+                                         tcpc->config->nr_snk_pdo);
+
+       port->max_snk_mv = tcpc->config->max_snk_mv;
+       port->max_snk_ma = tcpc->config->max_snk_ma;
+       port->max_snk_mw = tcpc->config->max_snk_mw;
+       port->operating_snk_mw = tcpc->config->operating_snk_mw;
+       if (!tcpc->config->try_role_hw)
+               port->try_role = tcpc->config->default_role;
+       else
+               port->try_role = TYPEC_NO_PREFERRED_ROLE;
+
+       port->typec_caps.prefer_role = tcpc->config->default_role;
+       port->typec_caps.type = tcpc->config->type;
+       port->typec_caps.revision = 0x0120;     /* Type-C spec release 1.2 */
+       port->typec_caps.pd_revision = 0x0200;  /* USB-PD spec release 2.0 */
+       port->typec_caps.dr_set = tcpm_dr_set;
+       port->typec_caps.pr_set = tcpm_pr_set;
+       port->typec_caps.vconn_set = tcpm_vconn_set;
+       port->typec_caps.try_role = tcpm_try_role;
+
+       port->partner_desc.identity = &port->partner_ident;
+
+       /*
+        * TODO:
+        *  - alt_modes, set_alt_mode
+        *  - {debug,audio}_accessory
+        */
+
+       port->typec_port = typec_register_port(port->dev, &port->typec_caps);
+       if (!port->typec_port) {
+               err = -ENOMEM;
+               goto out_destroy_wq;
+       }
+
+       if (tcpc->config->alt_modes) {
+               struct typec_altmode_desc *paltmode = tcpc->config->alt_modes;
+
+               i = 0;
+               while (paltmode->svid && i < ARRAY_SIZE(port->port_altmode)) {
+                       port->port_altmode[i] =
+                         typec_port_register_altmode(port->typec_port,
+                                                     paltmode);
+                       if (!port->port_altmode[i]) {
+                               tcpm_log(port,
+                                        "%s: failed to register port alternate mode 0x%x",
+                                        dev_name(dev), paltmode->svid);
+                               break;
+                       }
+                       i++;
+                       paltmode++;
+               }
+       }
+
+       tcpm_debugfs_init(port);
+       mutex_lock(&port->lock);
+       tcpm_init(port);
+       mutex_unlock(&port->lock);
+
+       tcpm_log(port, "%s: registered", dev_name(dev));
+       return port;
+
+out_destroy_wq:
+       destroy_workqueue(port->wq);
+       return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(tcpm_register_port);
+
+void tcpm_unregister_port(struct tcpm_port *port)
+{
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(port->port_altmode); i++)
+               typec_unregister_altmode(port->port_altmode[i]);
+       typec_unregister_port(port->typec_port);
+       tcpm_debugfs_exit(port);
+       destroy_workqueue(port->wq);
+}
+EXPORT_SYMBOL_GPL(tcpm_unregister_port);
+
+MODULE_AUTHOR("Guenter Roeck <groeck@chromium.org>");
+MODULE_DESCRIPTION("USB Type-C Port Manager");
+MODULE_LICENSE("GPL");
diff --git a/drivers/staging/typec/tcpm.h b/drivers/staging/typec/tcpm.h
new file mode 100644 (file)
index 0000000..969b365
--- /dev/null
@@ -0,0 +1,150 @@
+/*
+ * Copyright 2015-2017 Google, Inc
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __LINUX_USB_TCPM_H
+#define __LINUX_USB_TCPM_H
+
+#include <linux/bitops.h>
+#include <linux/usb/typec.h>
+#include "pd.h"
+
+enum typec_cc_status {
+       TYPEC_CC_OPEN,
+       TYPEC_CC_RA,
+       TYPEC_CC_RD,
+       TYPEC_CC_RP_DEF,
+       TYPEC_CC_RP_1_5,
+       TYPEC_CC_RP_3_0,
+};
+
+enum typec_cc_polarity {
+       TYPEC_POLARITY_CC1,
+       TYPEC_POLARITY_CC2,
+};
+
+/* Time to wait for TCPC to complete transmit */
+#define PD_T_TCPC_TX_TIMEOUT  100
+
+enum tcpm_transmit_status {
+       TCPC_TX_SUCCESS = 0,
+       TCPC_TX_DISCARDED = 1,
+       TCPC_TX_FAILED = 2,
+};
+
+enum tcpm_transmit_type {
+       TCPC_TX_SOP = 0,
+       TCPC_TX_SOP_PRIME = 1,
+       TCPC_TX_SOP_PRIME_PRIME = 2,
+       TCPC_TX_SOP_DEBUG_PRIME = 3,
+       TCPC_TX_SOP_DEBUG_PRIME_PRIME = 4,
+       TCPC_TX_HARD_RESET = 5,
+       TCPC_TX_CABLE_RESET = 6,
+       TCPC_TX_BIST_MODE_2 = 7
+};
+
+struct tcpc_config {
+       const u32 *src_pdo;
+       unsigned int nr_src_pdo;
+
+       const u32 *snk_pdo;
+       unsigned int nr_snk_pdo;
+
+       unsigned int max_snk_mv;
+       unsigned int max_snk_ma;
+       unsigned int max_snk_mw;
+       unsigned int operating_snk_mw;
+
+       enum typec_port_type type;
+       enum typec_role default_role;
+       bool try_role_hw;       /* try.{src,snk} implemented in hardware */
+
+       struct typec_altmode_desc *alt_modes;
+};
+
+enum tcpc_usb_switch {
+       TCPC_USB_SWITCH_CONNECT,
+       TCPC_USB_SWITCH_DISCONNECT,
+       TCPC_USB_SWITCH_RESTORE,        /* TODO FIXME */
+};
+
+/* Mux state attributes */
+#define TCPC_MUX_USB_ENABLED           BIT(0)  /* USB enabled */
+#define TCPC_MUX_DP_ENABLED            BIT(1)  /* DP enabled */
+#define TCPC_MUX_POLARITY_INVERTED     BIT(2)  /* Polarity inverted */
+
+/* Mux modes, decoded to attributes */
+enum tcpc_mux_mode {
+       TYPEC_MUX_NONE  = 0,                            /* Open switch */
+       TYPEC_MUX_USB   = TCPC_MUX_USB_ENABLED,         /* USB only */
+       TYPEC_MUX_DP    = TCPC_MUX_DP_ENABLED,          /* DP only */
+       TYPEC_MUX_DOCK  = TCPC_MUX_USB_ENABLED |        /* Both USB and DP */
+                         TCPC_MUX_DP_ENABLED,
+};
+
+struct tcpc_mux_dev {
+       int (*set)(struct tcpc_mux_dev *dev, enum tcpc_mux_mode mux_mode,
+                  enum tcpc_usb_switch usb_config,
+                  enum typec_cc_polarity polarity);
+       bool dfp_only;
+       void *priv_data;
+};
+
+struct tcpc_dev {
+       const struct tcpc_config *config;
+
+       int (*init)(struct tcpc_dev *dev);
+       int (*get_vbus)(struct tcpc_dev *dev);
+       int (*set_cc)(struct tcpc_dev *dev, enum typec_cc_status cc);
+       int (*get_cc)(struct tcpc_dev *dev, enum typec_cc_status *cc1,
+                     enum typec_cc_status *cc2);
+       int (*set_polarity)(struct tcpc_dev *dev,
+                           enum typec_cc_polarity polarity);
+       int (*set_vconn)(struct tcpc_dev *dev, bool on);
+       int (*set_vbus)(struct tcpc_dev *dev, bool on, bool charge);
+       int (*set_current_limit)(struct tcpc_dev *dev, u32 max_ma, u32 mv);
+       int (*set_pd_rx)(struct tcpc_dev *dev, bool on);
+       int (*set_roles)(struct tcpc_dev *dev, bool attached,
+                        enum typec_role role, enum typec_data_role data);
+       int (*start_drp_toggling)(struct tcpc_dev *dev,
+                                 enum typec_cc_status cc);
+       int (*try_role)(struct tcpc_dev *dev, int role);
+       int (*pd_transmit)(struct tcpc_dev *dev, enum tcpm_transmit_type type,
+                          const struct pd_message *msg);
+       struct tcpc_mux_dev *mux;
+};
+
+struct tcpm_port;
+
+struct tcpm_port *tcpm_register_port(struct device *dev, struct tcpc_dev *tcpc);
+void tcpm_unregister_port(struct tcpm_port *port);
+
+void tcpm_update_source_capabilities(struct tcpm_port *port, const u32 *pdo,
+                                    unsigned int nr_pdo);
+void tcpm_update_sink_capabilities(struct tcpm_port *port, const u32 *pdo,
+                                  unsigned int nr_pdo,
+                                  unsigned int max_snk_mv,
+                                  unsigned int max_snk_ma,
+                                  unsigned int max_snk_mw,
+                                  unsigned int operating_snk_mw);
+
+void tcpm_vbus_change(struct tcpm_port *port);
+void tcpm_cc_change(struct tcpm_port *port);
+void tcpm_pd_receive(struct tcpm_port *port,
+                    const struct pd_message *msg);
+void tcpm_pd_transmit_complete(struct tcpm_port *port,
+                              enum tcpm_transmit_status status);
+void tcpm_pd_hard_reset(struct tcpm_port *port);
+void tcpm_tcpc_reset(struct tcpm_port *port);
+
+#endif /* __LINUX_USB_TCPM_H */