--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+/*
+ * Infrared Toy and IR Droid RC core driver
+ *
+ * Copyright (C) 2020 Sean Young <sean@mess.org>
+
+ * This driver is based on the lirc driver which can be found here:
+ * https://sourceforge.net/p/lirc/git/ci/master/tree/plugins/irtoy.c
+ * Copyright (C) 2011 Peter Kooiman <pkooiman@gmail.com>
+ */
+
+#include <asm/unaligned.h>
+#include <linux/completion.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/slab.h>
+#include <linux/usb/input.h>
+
+#include <media/rc-core.h>
+
+static const u8 COMMAND_VERSION[] = { 'v' };
+// End transmit and repeat reset command so we exit sump mode
+static const u8 COMMAND_RESET[] = { 0xff, 0xff, 0, 0, 0, 0, 0 };
+static const u8 COMMAND_SMODE_ENTER[] = { 's' };
+static const u8 COMMAND_TXSTART[] = { 0x26, 0x24, 0x25, 0x03 };
+
+#define REPLY_XMITCOUNT 't'
+#define REPLY_XMITSUCCESS 'C'
+#define REPLY_VERSION 'V'
+#define REPLY_SAMPLEMODEPROTO 'S'
+
+#define TIMEOUT 500
+
+#define LEN_XMITRES 3
+#define LEN_VERSION 4
+#define LEN_SAMPLEMODEPROTO 3
+
+#define MIN_FW_VERSION 20
+#define UNIT_NS 21333
+#define MAX_TIMEOUT_NS (UNIT_NS * U16_MAX)
+
+#define MAX_PACKET 64
+
+enum state {
+ STATE_IRDATA,
+ STATE_RESET,
+ STATE_COMMAND,
+ STATE_TX,
+};
+
+struct irtoy {
+ struct device *dev;
+ struct usb_device *usbdev;
+
+ struct rc_dev *rc;
+ struct urb *urb_in, *urb_out;
+
+ u8 *in;
+ u8 *out;
+ struct completion command_done;
+
+ bool pulse;
+ enum state state;
+
+ void *tx_buf;
+ uint tx_len;
+
+ uint emitted;
+ uint hw_version;
+ uint sw_version;
+ uint proto_version;
+
+ char phys[64];
+};
+
+static void irtoy_response(struct irtoy *irtoy, u32 len)
+{
+ switch (irtoy->state) {
+ case STATE_COMMAND:
+ if (len == LEN_VERSION && irtoy->in[0] == REPLY_VERSION) {
+ uint version;
+
+ irtoy->in[LEN_VERSION] = 0;
+
+ if (kstrtouint(irtoy->in + 1, 10, &version)) {
+ dev_err(irtoy->dev, "invalid version %*phN. Please make sure you are using firmware v20 or higher",
+ LEN_VERSION, irtoy->in);
+ break;
+ }
+
+ dev_dbg(irtoy->dev, "version %s\n", irtoy->in);
+
+ irtoy->hw_version = version / 100;
+ irtoy->sw_version = version % 100;
+
+ irtoy->state = STATE_IRDATA;
+ complete(&irtoy->command_done);
+ } else if (len == LEN_SAMPLEMODEPROTO &&
+ irtoy->in[0] == REPLY_SAMPLEMODEPROTO) {
+ uint version;
+
+ irtoy->in[LEN_SAMPLEMODEPROTO] = 0;
+
+ if (kstrtouint(irtoy->in + 1, 10, &version)) {
+ dev_err(irtoy->dev, "invalid sample mode response %*phN",
+ LEN_SAMPLEMODEPROTO, irtoy->in);
+ return;
+ }
+
+ dev_dbg(irtoy->dev, "protocol %s\n", irtoy->in);
+
+ irtoy->proto_version = version;
+
+ irtoy->state = STATE_IRDATA;
+ complete(&irtoy->command_done);
+ } else {
+ dev_err(irtoy->dev, "unexpected response to command: %*phN\n",
+ len, irtoy->in);
+ }
+ break;
+ case STATE_IRDATA: {
+ struct ir_raw_event rawir = { .pulse = irtoy->pulse };
+ __be16 *in = (__be16 *)irtoy->in;
+ int i;
+
+ for (i = 0; i < len / sizeof(__be16); i++) {
+ u16 v = be16_to_cpu(in[i]);
+
+ if (v == 0xffff) {
+ rawir.pulse = false;
+ } else {
+ rawir.duration = v * UNIT_NS;
+ ir_raw_event_store_with_timeout(irtoy->rc,
+ &rawir);
+ }
+
+ rawir.pulse = !rawir.pulse;
+ }
+
+ irtoy->pulse = rawir.pulse;
+
+ ir_raw_event_handle(irtoy->rc);
+ break;
+ }
+ case STATE_TX:
+ if (irtoy->tx_len == 0) {
+ if (len == LEN_XMITRES &&
+ irtoy->in[0] == REPLY_XMITCOUNT) {
+ u16 emitted = get_unaligned_be16(irtoy->in + 1);
+
+ dev_dbg(irtoy->dev, "emitted:%u\n", emitted);
+
+ irtoy->emitted = emitted;
+ } else if (len == 1 &&
+ irtoy->in[0] == REPLY_XMITSUCCESS) {
+ irtoy->state = STATE_IRDATA;
+ complete(&irtoy->command_done);
+ }
+ } else {
+ // send next part of tx buffer
+ uint space = irtoy->in[0];
+ uint buf_len;
+ int err;
+
+ if (len != 1 || space > MAX_PACKET || space == 0) {
+ dev_err(irtoy->dev, "packet length expected: %*phN\n",
+ len, irtoy->in);
+ irtoy->state = STATE_IRDATA;
+ complete(&irtoy->command_done);
+ break;
+ }
+
+ buf_len = min(space, irtoy->tx_len);
+
+ dev_dbg(irtoy->dev, "remaining:%u sending:%u\n",
+ irtoy->tx_len, buf_len);
+
+ memcpy(irtoy->out, irtoy->tx_buf, buf_len);
+ irtoy->urb_out->transfer_buffer_length = buf_len;
+ err = usb_submit_urb(irtoy->urb_out, GFP_ATOMIC);
+ if (err != 0) {
+ dev_err(irtoy->dev, "fail to submit tx buf urb: %d\n",
+ err);
+ irtoy->state = STATE_IRDATA;
+ complete(&irtoy->command_done);
+ break;
+ }
+
+ irtoy->tx_buf += buf_len;
+ irtoy->tx_len -= buf_len;
+ }
+ break;
+ case STATE_RESET:
+ dev_err(irtoy->dev, "unexpected response to reset: %*phN\n",
+ len, irtoy->in);
+ }
+}
+
+static void irtoy_out_callback(struct urb *urb)
+{
+ struct irtoy *irtoy = urb->context;
+
+ if (urb->status == 0) {
+ if (irtoy->state == STATE_RESET)
+ complete(&irtoy->command_done);
+ } else {
+ dev_warn(irtoy->dev, "out urb status: %d\n", urb->status);
+ }
+}
+
+static void irtoy_in_callback(struct urb *urb)
+{
+ struct irtoy *irtoy = urb->context;
+ int ret;
+
+ if (urb->status == 0)
+ irtoy_response(irtoy, urb->actual_length);
+ else
+ dev_dbg(irtoy->dev, "in urb status: %d\n", urb->status);
+
+ ret = usb_submit_urb(urb, GFP_ATOMIC);
+ if (ret && ret != -ENODEV)
+ dev_warn(irtoy->dev, "failed to resubmit urb: %d\n", ret);
+}
+
+static int irtoy_command(struct irtoy *irtoy, const u8 *cmd, int cmd_len,
+ enum state state)
+{
+ int err;
+
+ init_completion(&irtoy->command_done);
+
+ irtoy->state = state;
+
+ memcpy(irtoy->out, cmd, cmd_len);
+ irtoy->urb_out->transfer_buffer_length = cmd_len;
+
+ err = usb_submit_urb(irtoy->urb_out, GFP_KERNEL);
+ if (err != 0)
+ return err;
+
+ if (!wait_for_completion_timeout(&irtoy->command_done,
+ msecs_to_jiffies(TIMEOUT))) {
+ usb_kill_urb(irtoy->urb_out);
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static int irtoy_setup(struct irtoy *irtoy)
+{
+ int err;
+
+ err = irtoy_command(irtoy, COMMAND_RESET, sizeof(COMMAND_RESET),
+ STATE_RESET);
+ if (err != 0) {
+ dev_err(irtoy->dev, "could not write reset command: %d\n",
+ err);
+ return err;
+ }
+
+ usleep_range(50, 50);
+
+ // get version
+ err = irtoy_command(irtoy, COMMAND_VERSION, sizeof(COMMAND_VERSION),
+ STATE_COMMAND);
+ if (err) {
+ dev_err(irtoy->dev, "could not write version command: %d\n",
+ err);
+ return err;
+ }
+
+ // enter sample mode
+ err = irtoy_command(irtoy, COMMAND_SMODE_ENTER,
+ sizeof(COMMAND_SMODE_ENTER), STATE_COMMAND);
+ if (err)
+ dev_err(irtoy->dev, "could not write sample command: %d\n",
+ err);
+
+ return err;
+}
+
+/*
+ * When sending IR, it is imperative that we send the IR data as quickly
+ * as possible to the device, so it does not run out of IR data and
+ * introduce gaps. Allocate the buffer here, and then feed the data from
+ * the urb callback handler.
+ */
+static int irtoy_tx(struct rc_dev *rc, uint *txbuf, uint count)
+{
+ struct irtoy *irtoy = rc->priv;
+ unsigned int i, size;
+ __be16 *buf;
+ int err;
+
+ size = sizeof(u16) * (count + 1);
+ buf = kmalloc(size, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ for (i = 0; i < count; i++) {
+ u16 v = DIV_ROUND_CLOSEST(US_TO_NS(txbuf[i]), UNIT_NS);
+
+ if (!v)
+ v = 1;
+ buf[i] = cpu_to_be16(v);
+ }
+
+ buf[count] = cpu_to_be16(0xffff);
+
+ irtoy->tx_buf = buf;
+ irtoy->tx_len = size;
+ irtoy->emitted = 0;
+
+ err = irtoy_command(irtoy, COMMAND_TXSTART, sizeof(COMMAND_TXSTART),
+ STATE_TX);
+ kfree(buf);
+
+ if (err) {
+ dev_err(irtoy->dev, "failed to send tx start command: %d\n",
+ err);
+ // not sure what state the device is in, reset it
+ irtoy_setup(irtoy);
+ return err;
+ }
+
+ if (size != irtoy->emitted) {
+ dev_err(irtoy->dev, "expected %u emitted, got %u\n", size,
+ irtoy->emitted);
+ // not sure what state the device is in, reset it
+ irtoy_setup(irtoy);
+ return -EINVAL;
+ }
+
+ return count;
+}
+
+static int irtoy_probe(struct usb_interface *intf,
+ const struct usb_device_id *id)
+{
+ struct usb_host_interface *idesc = intf->cur_altsetting;
+ struct usb_device *usbdev = interface_to_usbdev(intf);
+ struct usb_endpoint_descriptor *ep_in = NULL;
+ struct usb_endpoint_descriptor *ep_out = NULL;
+ struct usb_endpoint_descriptor *ep = NULL;
+ struct irtoy *irtoy;
+ struct rc_dev *rc;
+ struct urb *urb;
+ int i, pipe, err = -ENOMEM;
+
+ for (i = 0; i < idesc->desc.bNumEndpoints; i++) {
+ ep = &idesc->endpoint[i].desc;
+
+ if (!ep_in && usb_endpoint_is_bulk_in(ep) &&
+ usb_endpoint_maxp(ep) == MAX_PACKET)
+ ep_in = ep;
+
+ if (!ep_out && usb_endpoint_is_bulk_out(ep) &&
+ usb_endpoint_maxp(ep) == MAX_PACKET)
+ ep_out = ep;
+ }
+
+ if (!ep_in || !ep_out) {
+ dev_err(&intf->dev, "required endpoints not found\n");
+ return -ENODEV;
+ }
+
+ irtoy = kzalloc(sizeof(*irtoy), GFP_KERNEL);
+ if (!irtoy)
+ return -ENOMEM;
+
+ irtoy->in = kmalloc(MAX_PACKET, GFP_KERNEL);
+ if (!irtoy->in)
+ goto free_irtoy;
+
+ irtoy->out = kmalloc(MAX_PACKET, GFP_KERNEL);
+ if (!irtoy->out)
+ goto free_irtoy;
+
+ rc = rc_allocate_device(RC_DRIVER_IR_RAW);
+ if (!rc)
+ goto free_irtoy;
+
+ urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!urb)
+ goto free_rcdev;
+
+ pipe = usb_rcvbulkpipe(usbdev, ep_in->bEndpointAddress);
+ usb_fill_bulk_urb(urb, usbdev, pipe, irtoy->in, MAX_PACKET,
+ irtoy_in_callback, irtoy);
+ irtoy->urb_in = urb;
+
+ urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!urb)
+ goto free_rcdev;
+
+ pipe = usb_sndbulkpipe(usbdev, ep_out->bEndpointAddress);
+ usb_fill_bulk_urb(urb, usbdev, pipe, irtoy->out, MAX_PACKET,
+ irtoy_out_callback, irtoy);
+
+ irtoy->dev = &intf->dev;
+ irtoy->usbdev = usbdev;
+ irtoy->rc = rc;
+ irtoy->urb_out = urb;
+ irtoy->pulse = true;
+
+ err = usb_submit_urb(irtoy->urb_in, GFP_KERNEL);
+ if (err != 0) {
+ dev_err(irtoy->dev, "fail to submit in urb: %d\n", err);
+ return err;
+ }
+
+ err = irtoy_setup(irtoy);
+ if (err)
+ goto free_rcdev;
+
+ dev_info(irtoy->dev, "version: hardware %u, firmware %u, protocol %u",
+ irtoy->hw_version, irtoy->sw_version, irtoy->proto_version);
+
+ if (irtoy->sw_version < MIN_FW_VERSION) {
+ dev_err(irtoy->dev, "need firmware V%02u or higher",
+ MIN_FW_VERSION);
+ err = -ENODEV;
+ goto free_rcdev;
+ }
+
+ usb_make_path(usbdev, irtoy->phys, sizeof(irtoy->phys));
+
+ rc->device_name = "Infrared Toy";
+ rc->driver_name = KBUILD_MODNAME;
+ rc->input_phys = irtoy->phys;
+ usb_to_input_id(usbdev, &rc->input_id);
+ rc->dev.parent = &intf->dev;
+ rc->priv = irtoy;
+ rc->tx_ir = irtoy_tx;
+ rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
+ rc->map_name = RC_MAP_RC6_MCE;
+ rc->rx_resolution = UNIT_NS;
+ rc->timeout = IR_DEFAULT_TIMEOUT;
+
+ /*
+ * end of transmission is detected by absence of a usb packet
+ * with more pulse/spaces. However, each usb packet sent can
+ * contain 32 pulse/spaces, which can be quite lengthy, so there
+ * can be a delay between usb packets. For example with nec there is a
+ * 17ms gap between packets.
+ *
+ * So, make timeout a largish minimum which works with most protocols.
+ */
+ rc->min_timeout = MS_TO_NS(40);
+ rc->max_timeout = MAX_TIMEOUT_NS;
+
+ err = rc_register_device(rc);
+ if (err)
+ goto free_rcdev;
+
+ usb_set_intfdata(intf, irtoy);
+
+ return 0;
+
+free_rcdev:
+ usb_kill_urb(irtoy->urb_out);
+ usb_free_urb(irtoy->urb_out);
+ usb_kill_urb(irtoy->urb_in);
+ usb_free_urb(irtoy->urb_in);
+ rc_free_device(rc);
+free_irtoy:
+ kfree(irtoy->in);
+ kfree(irtoy->out);
+ kfree(irtoy);
+ return err;
+}
+
+static void irtoy_disconnect(struct usb_interface *intf)
+{
+ struct irtoy *ir = usb_get_intfdata(intf);
+
+ rc_unregister_device(ir->rc);
+ usb_set_intfdata(intf, NULL);
+ usb_kill_urb(ir->urb_out);
+ usb_free_urb(ir->urb_out);
+ usb_kill_urb(ir->urb_in);
+ usb_free_urb(ir->urb_in);
+ kfree(ir->in);
+ kfree(ir->out);
+ kfree(ir);
+}
+
+static const struct usb_device_id irtoy_table[] = {
+ { USB_DEVICE_INTERFACE_CLASS(0x04d8, 0xfd08, USB_CLASS_CDC_DATA) },
+ { }
+};
+
+static struct usb_driver irtoy_driver = {
+ .name = KBUILD_MODNAME,
+ .probe = irtoy_probe,
+ .disconnect = irtoy_disconnect,
+ .id_table = irtoy_table,
+};
+
+module_usb_driver(irtoy_driver);
+
+MODULE_AUTHOR("Sean Young <sean@mess.org>");
+MODULE_DESCRIPTION("Infrared Toy and IR Droid driver");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(usb, irtoy_table);