1 // SPDX-License-Identifier: GPL-2.0-or-later
2
3 /*
4 * Infrared Toy and IR Droid RC core driver
5 *
6 * Copyright (C) 2020 Sean Young <sean@mess.org>
7 *
8 * http://dangerousprototypes.com/docs/USB_IR_Toy:_Sampling_mode
9 *
10 * This driver is based on the lirc driver which can be found here:
11 * https://sourceforge.net/p/lirc/git/ci/master/tree/plugins/irtoy.c
12 * Copyright (C) 2011 Peter Kooiman <pkooiman@gmail.com>
13 */
14
15 #include <asm/unaligned.h>
16 #include <linux/completion.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/usb.h>
20 #include <linux/slab.h>
21 #include <linux/usb/input.h>
22
23 #include <media/rc-core.h>
24
25 static const u8 COMMAND_VERSION[] = { 'v' };
26 // End transmit and repeat reset command so we exit sump mode
27 static const u8 COMMAND_RESET[] = { 0xff, 0xff, 0, 0, 0, 0, 0 };
28 static const u8 COMMAND_SMODE_ENTER[] = { 's' };
29 static const u8 COMMAND_SMODE_EXIT[] = { 0 };
30 static const u8 COMMAND_TXSTART[] = { 0x26, 0x24, 0x25, 0x03 };
31
32 #define REPLY_XMITCOUNT 't'
33 #define REPLY_XMITSUCCESS 'C'
34 #define REPLY_VERSION 'V'
35 #define REPLY_SAMPLEMODEPROTO 'S'
36
37 #define TIMEOUT 500
38
39 #define LEN_XMITRES 3
40 #define LEN_VERSION 4
41 #define LEN_SAMPLEMODEPROTO 3
42
43 #define MIN_FW_VERSION 20
44 #define UNIT_US 21
45 #define MAX_TIMEOUT_US (UNIT_US * U16_MAX)
46
47 #define MAX_PACKET 64
48
49 enum state {
50 STATE_IRDATA,
51 STATE_COMMAND_NO_RESP,
52 STATE_COMMAND,
53 STATE_TX,
54 };
55
56 struct irtoy {
57 struct device *dev;
58 struct usb_device *usbdev;
59
60 struct rc_dev *rc;
61 struct urb *urb_in, *urb_out;
62
63 u8 *in;
64 u8 *out;
65 struct completion command_done;
66
67 bool pulse;
68 enum state state;
69
70 void *tx_buf;
71 uint tx_len;
72
73 uint emitted;
74 uint hw_version;
75 uint sw_version;
76 uint proto_version;
77
78 char phys[64];
79 };
80
irtoy_response(struct irtoy * irtoy,u32 len)81 static void irtoy_response(struct irtoy *irtoy, u32 len)
82 {
83 switch (irtoy->state) {
84 case STATE_COMMAND:
85 if (len == LEN_VERSION && irtoy->in[0] == REPLY_VERSION) {
86 uint version;
87
88 irtoy->in[LEN_VERSION] = 0;
89
90 if (kstrtouint(irtoy->in + 1, 10, &version)) {
91 dev_err(irtoy->dev, "invalid version %*phN. Please make sure you are using firmware v20 or higher",
92 LEN_VERSION, irtoy->in);
93 break;
94 }
95
96 dev_dbg(irtoy->dev, "version %s\n", irtoy->in);
97
98 irtoy->hw_version = version / 100;
99 irtoy->sw_version = version % 100;
100
101 irtoy->state = STATE_IRDATA;
102 complete(&irtoy->command_done);
103 } else if (len == LEN_SAMPLEMODEPROTO &&
104 irtoy->in[0] == REPLY_SAMPLEMODEPROTO) {
105 uint version;
106
107 irtoy->in[LEN_SAMPLEMODEPROTO] = 0;
108
109 if (kstrtouint(irtoy->in + 1, 10, &version)) {
110 dev_err(irtoy->dev, "invalid sample mode response %*phN",
111 LEN_SAMPLEMODEPROTO, irtoy->in);
112 return;
113 }
114
115 dev_dbg(irtoy->dev, "protocol %s\n", irtoy->in);
116
117 irtoy->proto_version = version;
118
119 irtoy->state = STATE_IRDATA;
120 complete(&irtoy->command_done);
121 } else {
122 dev_err(irtoy->dev, "unexpected response to command: %*phN\n",
123 len, irtoy->in);
124 }
125 break;
126 case STATE_COMMAND_NO_RESP:
127 case STATE_IRDATA: {
128 struct ir_raw_event rawir = { .pulse = irtoy->pulse };
129 __be16 *in = (__be16 *)irtoy->in;
130 int i;
131
132 for (i = 0; i < len / sizeof(__be16); i++) {
133 u16 v = be16_to_cpu(in[i]);
134
135 if (v == 0xffff) {
136 rawir.pulse = false;
137 } else {
138 rawir.duration = v * UNIT_US;
139 ir_raw_event_store_with_timeout(irtoy->rc,
140 &rawir);
141 }
142
143 rawir.pulse = !rawir.pulse;
144 }
145
146 irtoy->pulse = rawir.pulse;
147
148 ir_raw_event_handle(irtoy->rc);
149 break;
150 }
151 case STATE_TX:
152 if (irtoy->tx_len == 0) {
153 if (len == LEN_XMITRES &&
154 irtoy->in[0] == REPLY_XMITCOUNT) {
155 u16 emitted = get_unaligned_be16(irtoy->in + 1);
156
157 dev_dbg(irtoy->dev, "emitted:%u\n", emitted);
158
159 irtoy->emitted = emitted;
160 } else if (len == 1 &&
161 irtoy->in[0] == REPLY_XMITSUCCESS) {
162 irtoy->state = STATE_IRDATA;
163 complete(&irtoy->command_done);
164 }
165 } else {
166 // send next part of tx buffer
167 uint space = irtoy->in[0];
168 uint buf_len;
169 int err;
170
171 if (len != 1 || space > MAX_PACKET || space == 0) {
172 dev_dbg(irtoy->dev, "packet length expected: %*phN\n",
173 len, irtoy->in);
174 break;
175 }
176
177 buf_len = min(space, irtoy->tx_len);
178
179 dev_dbg(irtoy->dev, "remaining:%u sending:%u\n",
180 irtoy->tx_len, buf_len);
181
182 memcpy(irtoy->out, irtoy->tx_buf, buf_len);
183 irtoy->urb_out->transfer_buffer_length = buf_len;
184 err = usb_submit_urb(irtoy->urb_out, GFP_ATOMIC);
185 if (err != 0) {
186 dev_err(irtoy->dev, "fail to submit tx buf urb: %d\n",
187 err);
188 irtoy->state = STATE_IRDATA;
189 complete(&irtoy->command_done);
190 break;
191 }
192
193 irtoy->tx_buf += buf_len;
194 irtoy->tx_len -= buf_len;
195 }
196 break;
197 }
198 }
199
irtoy_out_callback(struct urb * urb)200 static void irtoy_out_callback(struct urb *urb)
201 {
202 struct irtoy *irtoy = urb->context;
203
204 if (urb->status == 0) {
205 if (irtoy->state == STATE_COMMAND_NO_RESP)
206 complete(&irtoy->command_done);
207 } else {
208 dev_warn(irtoy->dev, "out urb status: %d\n", urb->status);
209 }
210 }
211
irtoy_in_callback(struct urb * urb)212 static void irtoy_in_callback(struct urb *urb)
213 {
214 struct irtoy *irtoy = urb->context;
215 int ret;
216
217 switch (urb->status) {
218 case 0:
219 irtoy_response(irtoy, urb->actual_length);
220 break;
221 case -ECONNRESET:
222 case -ENOENT:
223 case -ESHUTDOWN:
224 case -EPROTO:
225 case -EPIPE:
226 usb_unlink_urb(urb);
227 return;
228 default:
229 dev_dbg(irtoy->dev, "in urb status: %d\n", urb->status);
230 }
231
232 ret = usb_submit_urb(urb, GFP_ATOMIC);
233 if (ret && ret != -ENODEV)
234 dev_warn(irtoy->dev, "failed to resubmit urb: %d\n", ret);
235 }
236
irtoy_command(struct irtoy * irtoy,const u8 * cmd,int cmd_len,enum state state)237 static int irtoy_command(struct irtoy *irtoy, const u8 *cmd, int cmd_len,
238 enum state state)
239 {
240 int err;
241
242 init_completion(&irtoy->command_done);
243
244 irtoy->state = state;
245
246 memcpy(irtoy->out, cmd, cmd_len);
247 irtoy->urb_out->transfer_buffer_length = cmd_len;
248
249 err = usb_submit_urb(irtoy->urb_out, GFP_KERNEL);
250 if (err != 0)
251 return err;
252
253 if (!wait_for_completion_timeout(&irtoy->command_done,
254 msecs_to_jiffies(TIMEOUT))) {
255 usb_kill_urb(irtoy->urb_out);
256 return -ETIMEDOUT;
257 }
258
259 return 0;
260 }
261
irtoy_setup(struct irtoy * irtoy)262 static int irtoy_setup(struct irtoy *irtoy)
263 {
264 int err;
265
266 err = irtoy_command(irtoy, COMMAND_RESET, sizeof(COMMAND_RESET),
267 STATE_COMMAND_NO_RESP);
268 if (err != 0) {
269 dev_err(irtoy->dev, "could not write reset command: %d\n",
270 err);
271 return err;
272 }
273
274 usleep_range(50, 50);
275
276 // get version
277 err = irtoy_command(irtoy, COMMAND_VERSION, sizeof(COMMAND_VERSION),
278 STATE_COMMAND);
279 if (err) {
280 dev_err(irtoy->dev, "could not write version command: %d\n",
281 err);
282 return err;
283 }
284
285 // enter sample mode
286 err = irtoy_command(irtoy, COMMAND_SMODE_ENTER,
287 sizeof(COMMAND_SMODE_ENTER), STATE_COMMAND);
288 if (err)
289 dev_err(irtoy->dev, "could not write sample command: %d\n",
290 err);
291
292 return err;
293 }
294
295 /*
296 * When sending IR, it is imperative that we send the IR data as quickly
297 * as possible to the device, so it does not run out of IR data and
298 * introduce gaps. Allocate the buffer here, and then feed the data from
299 * the urb callback handler.
300 */
irtoy_tx(struct rc_dev * rc,uint * txbuf,uint count)301 static int irtoy_tx(struct rc_dev *rc, uint *txbuf, uint count)
302 {
303 struct irtoy *irtoy = rc->priv;
304 unsigned int i, size;
305 __be16 *buf;
306 int err;
307
308 size = sizeof(u16) * (count + 1);
309 buf = kmalloc(size, GFP_KERNEL);
310 if (!buf)
311 return -ENOMEM;
312
313 for (i = 0; i < count; i++) {
314 u16 v = DIV_ROUND_CLOSEST(txbuf[i], UNIT_US);
315
316 if (!v)
317 v = 1;
318 buf[i] = cpu_to_be16(v);
319 }
320
321 buf[count] = cpu_to_be16(0xffff);
322
323 irtoy->tx_buf = buf;
324 irtoy->tx_len = size;
325 irtoy->emitted = 0;
326
327 // There is an issue where if the unit is receiving IR while the
328 // first TXSTART command is sent, the device might end up hanging
329 // with its led on. It does not respond to any command when this
330 // happens. To work around this, re-enter sample mode.
331 err = irtoy_command(irtoy, COMMAND_SMODE_EXIT,
332 sizeof(COMMAND_SMODE_EXIT), STATE_COMMAND_NO_RESP);
333 if (err) {
334 dev_err(irtoy->dev, "exit sample mode: %d\n", err);
335 kfree(buf);
336 return err;
337 }
338
339 err = irtoy_command(irtoy, COMMAND_SMODE_ENTER,
340 sizeof(COMMAND_SMODE_ENTER), STATE_COMMAND);
341 if (err) {
342 dev_err(irtoy->dev, "enter sample mode: %d\n", err);
343 kfree(buf);
344 return err;
345 }
346
347 err = irtoy_command(irtoy, COMMAND_TXSTART, sizeof(COMMAND_TXSTART),
348 STATE_TX);
349 kfree(buf);
350
351 if (err) {
352 dev_err(irtoy->dev, "failed to send tx start command: %d\n",
353 err);
354 // not sure what state the device is in, reset it
355 irtoy_setup(irtoy);
356 return err;
357 }
358
359 if (size != irtoy->emitted) {
360 dev_err(irtoy->dev, "expected %u emitted, got %u\n", size,
361 irtoy->emitted);
362 // not sure what state the device is in, reset it
363 irtoy_setup(irtoy);
364 return -EINVAL;
365 }
366
367 return count;
368 }
369
irtoy_tx_carrier(struct rc_dev * rc,uint32_t carrier)370 static int irtoy_tx_carrier(struct rc_dev *rc, uint32_t carrier)
371 {
372 struct irtoy *irtoy = rc->priv;
373 u8 buf[3];
374 int err;
375
376 if (carrier < 11800)
377 return -EINVAL;
378
379 buf[0] = 0x06;
380 buf[1] = DIV_ROUND_CLOSEST(48000000, 16 * carrier) - 1;
381 buf[2] = 0;
382
383 err = irtoy_command(irtoy, buf, sizeof(buf), STATE_COMMAND_NO_RESP);
384 if (err)
385 dev_err(irtoy->dev, "could not write carrier command: %d\n",
386 err);
387
388 return err;
389 }
390
irtoy_probe(struct usb_interface * intf,const struct usb_device_id * id)391 static int irtoy_probe(struct usb_interface *intf,
392 const struct usb_device_id *id)
393 {
394 struct usb_host_interface *idesc = intf->cur_altsetting;
395 struct usb_device *usbdev = interface_to_usbdev(intf);
396 struct usb_endpoint_descriptor *ep_in = NULL;
397 struct usb_endpoint_descriptor *ep_out = NULL;
398 struct usb_endpoint_descriptor *ep = NULL;
399 struct irtoy *irtoy;
400 struct rc_dev *rc;
401 struct urb *urb;
402 int i, pipe, err = -ENOMEM;
403
404 for (i = 0; i < idesc->desc.bNumEndpoints; i++) {
405 ep = &idesc->endpoint[i].desc;
406
407 if (!ep_in && usb_endpoint_is_bulk_in(ep) &&
408 usb_endpoint_maxp(ep) == MAX_PACKET)
409 ep_in = ep;
410
411 if (!ep_out && usb_endpoint_is_bulk_out(ep) &&
412 usb_endpoint_maxp(ep) == MAX_PACKET)
413 ep_out = ep;
414 }
415
416 if (!ep_in || !ep_out) {
417 dev_err(&intf->dev, "required endpoints not found\n");
418 return -ENODEV;
419 }
420
421 irtoy = kzalloc(sizeof(*irtoy), GFP_KERNEL);
422 if (!irtoy)
423 return -ENOMEM;
424
425 irtoy->in = kmalloc(MAX_PACKET, GFP_KERNEL);
426 if (!irtoy->in)
427 goto free_irtoy;
428
429 irtoy->out = kmalloc(MAX_PACKET, GFP_KERNEL);
430 if (!irtoy->out)
431 goto free_irtoy;
432
433 rc = rc_allocate_device(RC_DRIVER_IR_RAW);
434 if (!rc)
435 goto free_irtoy;
436
437 urb = usb_alloc_urb(0, GFP_KERNEL);
438 if (!urb)
439 goto free_rcdev;
440
441 pipe = usb_rcvbulkpipe(usbdev, ep_in->bEndpointAddress);
442 usb_fill_bulk_urb(urb, usbdev, pipe, irtoy->in, MAX_PACKET,
443 irtoy_in_callback, irtoy);
444 irtoy->urb_in = urb;
445
446 urb = usb_alloc_urb(0, GFP_KERNEL);
447 if (!urb)
448 goto free_rcdev;
449
450 pipe = usb_sndbulkpipe(usbdev, ep_out->bEndpointAddress);
451 usb_fill_bulk_urb(urb, usbdev, pipe, irtoy->out, MAX_PACKET,
452 irtoy_out_callback, irtoy);
453
454 irtoy->dev = &intf->dev;
455 irtoy->usbdev = usbdev;
456 irtoy->rc = rc;
457 irtoy->urb_out = urb;
458 irtoy->pulse = true;
459
460 err = usb_submit_urb(irtoy->urb_in, GFP_KERNEL);
461 if (err != 0) {
462 dev_err(irtoy->dev, "fail to submit in urb: %d\n", err);
463 goto free_rcdev;
464 }
465
466 err = irtoy_setup(irtoy);
467 if (err)
468 goto free_rcdev;
469
470 dev_info(irtoy->dev, "version: hardware %u, firmware %u.%u, protocol %u",
471 irtoy->hw_version, irtoy->sw_version / 10,
472 irtoy->sw_version % 10, irtoy->proto_version);
473
474 if (irtoy->sw_version < MIN_FW_VERSION) {
475 dev_err(irtoy->dev, "need firmware V%02u or higher",
476 MIN_FW_VERSION);
477 err = -ENODEV;
478 goto free_rcdev;
479 }
480
481 usb_make_path(usbdev, irtoy->phys, sizeof(irtoy->phys));
482
483 rc->device_name = "Infrared Toy";
484 rc->driver_name = KBUILD_MODNAME;
485 rc->input_phys = irtoy->phys;
486 usb_to_input_id(usbdev, &rc->input_id);
487 rc->dev.parent = &intf->dev;
488 rc->priv = irtoy;
489 rc->tx_ir = irtoy_tx;
490 rc->s_tx_carrier = irtoy_tx_carrier;
491 rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
492 rc->map_name = RC_MAP_RC6_MCE;
493 rc->rx_resolution = UNIT_US;
494 rc->timeout = IR_DEFAULT_TIMEOUT;
495
496 /*
497 * end of transmission is detected by absence of a usb packet
498 * with more pulse/spaces. However, each usb packet sent can
499 * contain 32 pulse/spaces, which can be quite lengthy, so there
500 * can be a delay between usb packets. For example with nec there is a
501 * 17ms gap between packets.
502 *
503 * So, make timeout a largish minimum which works with most protocols.
504 */
505 rc->min_timeout = MS_TO_US(40);
506 rc->max_timeout = MAX_TIMEOUT_US;
507
508 err = rc_register_device(rc);
509 if (err)
510 goto free_rcdev;
511
512 usb_set_intfdata(intf, irtoy);
513
514 return 0;
515
516 free_rcdev:
517 usb_kill_urb(irtoy->urb_out);
518 usb_free_urb(irtoy->urb_out);
519 usb_kill_urb(irtoy->urb_in);
520 usb_free_urb(irtoy->urb_in);
521 rc_free_device(rc);
522 free_irtoy:
523 kfree(irtoy->in);
524 kfree(irtoy->out);
525 kfree(irtoy);
526 return err;
527 }
528
irtoy_disconnect(struct usb_interface * intf)529 static void irtoy_disconnect(struct usb_interface *intf)
530 {
531 struct irtoy *ir = usb_get_intfdata(intf);
532
533 rc_unregister_device(ir->rc);
534 usb_set_intfdata(intf, NULL);
535 usb_kill_urb(ir->urb_out);
536 usb_free_urb(ir->urb_out);
537 usb_kill_urb(ir->urb_in);
538 usb_free_urb(ir->urb_in);
539 kfree(ir->in);
540 kfree(ir->out);
541 kfree(ir);
542 }
543
544 static const struct usb_device_id irtoy_table[] = {
545 { USB_DEVICE_INTERFACE_CLASS(0x04d8, 0xfd08, USB_CLASS_CDC_DATA) },
546 { USB_DEVICE_INTERFACE_CLASS(0x04d8, 0xf58b, USB_CLASS_CDC_DATA) },
547 { }
548 };
549
550 static struct usb_driver irtoy_driver = {
551 .name = KBUILD_MODNAME,
552 .probe = irtoy_probe,
553 .disconnect = irtoy_disconnect,
554 .id_table = irtoy_table,
555 };
556
557 module_usb_driver(irtoy_driver);
558
559 MODULE_AUTHOR("Sean Young <sean@mess.org>");
560 MODULE_DESCRIPTION("Infrared Toy and IR Droid driver");
561 MODULE_LICENSE("GPL");
562 MODULE_DEVICE_TABLE(usb, irtoy_table);
563