1 /* SPDX-License-Identifier: GPL-2.0 */
3 * ChromeOS Embedded Controller protocol interface.
5 * Copyright (C) 2012 Google, Inc
8 #ifndef __LINUX_CROS_EC_PROTO_H
9 #define __LINUX_CROS_EC_PROTO_H
11 #include <linux/device.h>
12 #include <linux/mutex.h>
13 #include <linux/notifier.h>
15 #include <linux/mfd/cros_ec.h>
16 #include <linux/platform_data/cros_ec_commands.h>
18 #define CROS_EC_DEV_NAME "cros_ec"
19 #define CROS_EC_DEV_FP_NAME "cros_fp"
20 #define CROS_EC_DEV_ISH_NAME "cros_ish"
21 #define CROS_EC_DEV_PD_NAME "cros_pd"
22 #define CROS_EC_DEV_SCP_NAME "cros_scp"
23 #define CROS_EC_DEV_TP_NAME "cros_tp"
26 * The EC is unresponsive for a time after a reboot command. Add a
27 * simple delay to make sure that the bus stays locked.
29 #define EC_REBOOT_DELAY_MS 50
32 * Max bus-specific overhead incurred by request/responses.
33 * I2C requires 1 additional byte for requests.
34 * I2C requires 2 additional bytes for responses.
35 * SPI requires up to 32 additional bytes for responses.
37 #define EC_PROTO_VERSION_UNKNOWN 0
38 #define EC_MAX_REQUEST_OVERHEAD 1
39 #define EC_MAX_RESPONSE_OVERHEAD 32
42 * Command interface between EC and AP, for LPC, I2C and SPI interfaces.
45 EC_MSG_TX_HEADER_BYTES = 3,
46 EC_MSG_TX_TRAILER_BYTES = 1,
47 EC_MSG_TX_PROTO_BYTES = EC_MSG_TX_HEADER_BYTES +
48 EC_MSG_TX_TRAILER_BYTES,
49 EC_MSG_RX_PROTO_BYTES = 3,
51 /* Max length of messages for proto 2*/
52 EC_PROTO2_MSG_BYTES = EC_PROTO2_MAX_PARAM_SIZE +
53 EC_MSG_TX_PROTO_BYTES,
55 EC_MAX_MSG_BYTES = 64 * 1024,
59 * struct cros_ec_command - Information about a ChromeOS EC command.
60 * @version: Command version number (often 0).
61 * @command: Command to send (EC_CMD_...).
62 * @outsize: Outgoing length in bytes.
63 * @insize: Max number of bytes to accept from the EC.
64 * @result: EC's response to the command (separate from communication failure).
65 * @data: Where to put the incoming data from EC and outgoing data to EC.
67 struct cros_ec_command {
77 * struct cros_ec_device - Information about a ChromeOS EC device.
78 * @phys_name: Name of physical comms layer (e.g. 'i2c-4').
79 * @dev: Device pointer for physical comms device
80 * @was_wake_device: True if this device was set to wake the system from
81 * sleep at the last suspend.
82 * @cros_class: The class structure for this device.
83 * @cmd_readmem: Direct read of the EC memory-mapped region, if supported.
84 * @offset: Is within EC_LPC_ADDR_MEMMAP region.
85 * @bytes: Number of bytes to read. zero means "read a string" (including
86 * the trailing '\0'). At most only EC_MEMMAP_SIZE bytes can be
87 * read. Caller must ensure that the buffer is large enough for the
88 * result when reading a string.
89 * @max_request: Max size of message requested.
90 * @max_response: Max size of message response.
91 * @max_passthru: Max sice of passthru message.
92 * @proto_version: The protocol version used for this device.
93 * @priv: Private data.
94 * @irq: Interrupt to use.
96 * @din: Input buffer (for data from EC). This buffer will always be
97 * dword-aligned and include enough space for up to 7 word-alignment
98 * bytes also, so we can ensure that the body of the message is always
99 * dword-aligned (64-bit). We use this alignment to keep ARM and x86
100 * happy. Probably word alignment would be OK, there might be a small
101 * performance advantage to using dword.
102 * @dout: Output buffer (for data to EC). This buffer will always be
103 * dword-aligned and include enough space for up to 7 word-alignment
104 * bytes also, so we can ensure that the body of the message is always
105 * dword-aligned (64-bit). We use this alignment to keep ARM and x86
106 * happy. Probably word alignment would be OK, there might be a small
107 * performance advantage to using dword.
108 * @din_size: Size of din buffer to allocate (zero to use static din).
109 * @dout_size: Size of dout buffer to allocate (zero to use static dout).
110 * @wake_enabled: True if this device can wake the system from sleep.
111 * @suspended: True if this device had been suspended.
112 * @cmd_xfer: Send command to EC and get response.
113 * Returns the number of bytes received if the communication
114 * succeeded, but that doesn't mean the EC was happy with the
115 * command. The caller should check msg.result for the EC's result
117 * @pkt_xfer: Send packet to EC and get response.
118 * @lock: One transaction at a time.
119 * @mkbp_event_supported: 0 if MKBP not supported. Otherwise its value is
120 * the maximum supported version of the MKBP host event
122 * @host_sleep_v1: True if this EC supports the sleep v1 command.
123 * @event_notifier: Interrupt event notifier for transport devices.
124 * @event_data: Raw payload transferred with the MKBP event.
125 * @event_size: Size in bytes of the event data.
126 * @host_event_wake_mask: Mask of host events that cause wake from suspend.
127 * @last_event_time: exact time from the hard irq when we got notified of
129 * @ec: The platform_device used by the mfd driver to interface with the
131 * @pd: The platform_device used by the mfd driver to interface with the
134 struct cros_ec_device {
135 /* These are used by other drivers that want to talk to the EC */
136 const char *phys_name;
138 bool was_wake_device;
139 struct class *cros_class;
140 int (*cmd_readmem)(struct cros_ec_device *ec, unsigned int offset,
141 unsigned int bytes, void *dest);
143 /* These are used to implement the platform-specific interface */
156 int (*cmd_xfer)(struct cros_ec_device *ec,
157 struct cros_ec_command *msg);
158 int (*pkt_xfer)(struct cros_ec_device *ec,
159 struct cros_ec_command *msg);
161 u8 mkbp_event_supported;
163 struct blocking_notifier_head event_notifier;
165 struct ec_response_get_next_event_v1 event_data;
167 u32 host_event_wake_mask;
168 u32 last_resume_result;
169 ktime_t last_event_time;
171 /* The platform devices used by the mfd driver */
172 struct platform_device *ec;
173 struct platform_device *pd;
177 * struct cros_ec_platform - ChromeOS EC platform information.
178 * @ec_name: Name of EC device (e.g. 'cros-ec', 'cros-pd', ...)
179 * used in /dev/ and sysfs.
180 * @cmd_offset: Offset to apply for each command. Set when
181 * registering a device behind another one.
183 struct cros_ec_platform {
188 int cros_ec_suspend(struct cros_ec_device *ec_dev);
190 int cros_ec_resume(struct cros_ec_device *ec_dev);
192 int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
193 struct cros_ec_command *msg);
195 int cros_ec_check_result(struct cros_ec_device *ec_dev,
196 struct cros_ec_command *msg);
198 int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
199 struct cros_ec_command *msg);
201 int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev,
202 struct cros_ec_command *msg);
204 int cros_ec_register(struct cros_ec_device *ec_dev);
206 int cros_ec_unregister(struct cros_ec_device *ec_dev);
208 int cros_ec_query_all(struct cros_ec_device *ec_dev);
210 int cros_ec_get_next_event(struct cros_ec_device *ec_dev,
212 bool *has_more_events);
214 u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev);
216 int cros_ec_check_features(struct cros_ec_dev *ec, int feature);
218 int cros_ec_get_sensor_count(struct cros_ec_dev *ec);
220 bool cros_ec_handle_event(struct cros_ec_device *ec_dev);
223 * cros_ec_get_time_ns() - Return time in ns.
225 * This is the function used to record the time for last_event_time in struct
226 * cros_ec_device during the hard irq.
228 * Return: ktime_t format since boot.
230 static inline ktime_t cros_ec_get_time_ns(void)
232 return ktime_get_boottime_ns();
235 #endif /* __LINUX_CROS_EC_PROTO_H */