1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * IguanaWorks USB IR Transceiver support
4 *
5 * Copyright (C) 2012 Sean Young <sean@mess.org>
6 */
7
8 #include <linux/device.h>
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/usb.h>
12 #include <linux/usb/input.h>
13 #include <linux/slab.h>
14 #include <linux/completion.h>
15 #include <media/rc-core.h>
16
17 #define BUF_SIZE 152
18
19 struct iguanair {
20 struct rc_dev *rc;
21
22 struct device *dev;
23 struct usb_device *udev;
24
25 uint16_t version;
26 uint8_t bufsize;
27 uint8_t cycle_overhead;
28
29 /* receiver support */
30 bool receiver_on;
31 dma_addr_t dma_in, dma_out;
32 uint8_t *buf_in;
33 struct urb *urb_in, *urb_out;
34 struct completion completion;
35
36 /* transmit support */
37 bool tx_overflow;
38 uint32_t carrier;
39 struct send_packet *packet;
40
41 char name[64];
42 char phys[64];
43 };
44
45 #define CMD_NOP 0x00
46 #define CMD_GET_VERSION 0x01
47 #define CMD_GET_BUFSIZE 0x11
48 #define CMD_GET_FEATURES 0x10
49 #define CMD_SEND 0x15
50 #define CMD_EXECUTE 0x1f
51 #define CMD_RX_OVERFLOW 0x31
52 #define CMD_TX_OVERFLOW 0x32
53 #define CMD_RECEIVER_ON 0x12
54 #define CMD_RECEIVER_OFF 0x14
55
56 #define DIR_IN 0xdc
57 #define DIR_OUT 0xcd
58
59 #define MAX_IN_PACKET 8u
60 #define MAX_OUT_PACKET (sizeof(struct send_packet) + BUF_SIZE)
61 #define TIMEOUT 1000
62 #define RX_RESOLUTION 21
63
64 struct packet {
65 uint16_t start;
66 uint8_t direction;
67 uint8_t cmd;
68 };
69
70 struct send_packet {
71 struct packet header;
72 uint8_t length;
73 uint8_t channels;
74 uint8_t busy7;
75 uint8_t busy4;
76 uint8_t payload[];
77 };
78
process_ir_data(struct iguanair * ir,unsigned len)79 static void process_ir_data(struct iguanair *ir, unsigned len)
80 {
81 if (len >= 4 && ir->buf_in[0] == 0 && ir->buf_in[1] == 0) {
82 switch (ir->buf_in[3]) {
83 case CMD_GET_VERSION:
84 if (len == 6) {
85 ir->version = (ir->buf_in[5] << 8) |
86 ir->buf_in[4];
87 complete(&ir->completion);
88 }
89 break;
90 case CMD_GET_BUFSIZE:
91 if (len >= 5) {
92 ir->bufsize = ir->buf_in[4];
93 complete(&ir->completion);
94 }
95 break;
96 case CMD_GET_FEATURES:
97 if (len > 5) {
98 ir->cycle_overhead = ir->buf_in[5];
99 complete(&ir->completion);
100 }
101 break;
102 case CMD_TX_OVERFLOW:
103 ir->tx_overflow = true;
104 fallthrough;
105 case CMD_RECEIVER_OFF:
106 case CMD_RECEIVER_ON:
107 case CMD_SEND:
108 complete(&ir->completion);
109 break;
110 case CMD_RX_OVERFLOW:
111 dev_warn(ir->dev, "receive overflow\n");
112 ir_raw_event_overflow(ir->rc);
113 break;
114 default:
115 dev_warn(ir->dev, "control code %02x received\n",
116 ir->buf_in[3]);
117 break;
118 }
119 } else if (len >= 7) {
120 struct ir_raw_event rawir = {};
121 unsigned i;
122 bool event = false;
123
124 for (i = 0; i < 7; i++) {
125 if (ir->buf_in[i] == 0x80) {
126 rawir.pulse = false;
127 rawir.duration = 21845;
128 } else {
129 rawir.pulse = (ir->buf_in[i] & 0x80) == 0;
130 rawir.duration = ((ir->buf_in[i] & 0x7f) + 1) *
131 RX_RESOLUTION;
132 }
133
134 if (ir_raw_event_store_with_filter(ir->rc, &rawir))
135 event = true;
136 }
137
138 if (event)
139 ir_raw_event_handle(ir->rc);
140 }
141 }
142
iguanair_rx(struct urb * urb)143 static void iguanair_rx(struct urb *urb)
144 {
145 struct iguanair *ir;
146 int rc;
147
148 if (!urb)
149 return;
150
151 ir = urb->context;
152 if (!ir)
153 return;
154
155 switch (urb->status) {
156 case 0:
157 process_ir_data(ir, urb->actual_length);
158 break;
159 case -ECONNRESET:
160 case -ENOENT:
161 case -ESHUTDOWN:
162 return;
163 case -EPIPE:
164 default:
165 dev_dbg(ir->dev, "Error: urb status = %d\n", urb->status);
166 break;
167 }
168
169 rc = usb_submit_urb(urb, GFP_ATOMIC);
170 if (rc && rc != -ENODEV)
171 dev_warn(ir->dev, "failed to resubmit urb: %d\n", rc);
172 }
173
iguanair_irq_out(struct urb * urb)174 static void iguanair_irq_out(struct urb *urb)
175 {
176 struct iguanair *ir = urb->context;
177
178 if (urb->status)
179 dev_dbg(ir->dev, "Error: out urb status = %d\n", urb->status);
180
181 /* if we sent an nop packet, do not expect a response */
182 if (urb->status == 0 && ir->packet->header.cmd == CMD_NOP)
183 complete(&ir->completion);
184 }
185
iguanair_send(struct iguanair * ir,unsigned size)186 static int iguanair_send(struct iguanair *ir, unsigned size)
187 {
188 int rc;
189
190 reinit_completion(&ir->completion);
191
192 ir->urb_out->transfer_buffer_length = size;
193 rc = usb_submit_urb(ir->urb_out, GFP_KERNEL);
194 if (rc)
195 return rc;
196
197 if (wait_for_completion_timeout(&ir->completion, TIMEOUT) == 0)
198 return -ETIMEDOUT;
199
200 return rc;
201 }
202
iguanair_get_features(struct iguanair * ir)203 static int iguanair_get_features(struct iguanair *ir)
204 {
205 int rc;
206
207 /*
208 * On cold boot, the iguanair initializes on the first packet
209 * received but does not process that packet. Send an empty
210 * packet.
211 */
212 ir->packet->header.start = 0;
213 ir->packet->header.direction = DIR_OUT;
214 ir->packet->header.cmd = CMD_NOP;
215 iguanair_send(ir, sizeof(ir->packet->header));
216
217 ir->packet->header.cmd = CMD_GET_VERSION;
218 rc = iguanair_send(ir, sizeof(ir->packet->header));
219 if (rc) {
220 dev_info(ir->dev, "failed to get version\n");
221 goto out;
222 }
223
224 if (ir->version < 0x205) {
225 dev_err(ir->dev, "firmware 0x%04x is too old\n", ir->version);
226 rc = -ENODEV;
227 goto out;
228 }
229
230 ir->bufsize = 150;
231 ir->cycle_overhead = 65;
232
233 ir->packet->header.cmd = CMD_GET_BUFSIZE;
234
235 rc = iguanair_send(ir, sizeof(ir->packet->header));
236 if (rc) {
237 dev_info(ir->dev, "failed to get buffer size\n");
238 goto out;
239 }
240
241 if (ir->bufsize > BUF_SIZE) {
242 dev_info(ir->dev, "buffer size %u larger than expected\n",
243 ir->bufsize);
244 ir->bufsize = BUF_SIZE;
245 }
246
247 ir->packet->header.cmd = CMD_GET_FEATURES;
248
249 rc = iguanair_send(ir, sizeof(ir->packet->header));
250 if (rc)
251 dev_info(ir->dev, "failed to get features\n");
252 out:
253 return rc;
254 }
255
iguanair_receiver(struct iguanair * ir,bool enable)256 static int iguanair_receiver(struct iguanair *ir, bool enable)
257 {
258 ir->packet->header.start = 0;
259 ir->packet->header.direction = DIR_OUT;
260 ir->packet->header.cmd = enable ? CMD_RECEIVER_ON : CMD_RECEIVER_OFF;
261
262 return iguanair_send(ir, sizeof(ir->packet->header));
263 }
264
265 /*
266 * The iguanair creates the carrier by busy spinning after each half period.
267 * This is counted in CPU cycles, with the CPU running at 24MHz. It is
268 * broken down into 7-cycles and 4-cyles delays, with a preference for
269 * 4-cycle delays, minus the overhead of the loop itself (cycle_overhead).
270 */
iguanair_set_tx_carrier(struct rc_dev * dev,uint32_t carrier)271 static int iguanair_set_tx_carrier(struct rc_dev *dev, uint32_t carrier)
272 {
273 struct iguanair *ir = dev->priv;
274
275 if (carrier < 25000 || carrier > 150000)
276 return -EINVAL;
277
278 if (carrier != ir->carrier) {
279 uint32_t cycles, fours, sevens;
280
281 ir->carrier = carrier;
282
283 cycles = DIV_ROUND_CLOSEST(24000000, carrier * 2) -
284 ir->cycle_overhead;
285
286 /*
287 * Calculate minimum number of 7 cycles needed so
288 * we are left with a multiple of 4; so we want to have
289 * (sevens * 7) & 3 == cycles & 3
290 */
291 sevens = (4 - cycles) & 3;
292 fours = (cycles - sevens * 7) / 4;
293
294 /*
295 * The firmware interprets these values as a relative offset
296 * for a branch. Immediately following the branches, there
297 * 4 instructions of 7 cycles (2 bytes each) and 110
298 * instructions of 4 cycles (1 byte each). A relative branch
299 * of 0 will execute all of them, branch further for less
300 * cycle burning.
301 */
302 ir->packet->busy7 = (4 - sevens) * 2;
303 ir->packet->busy4 = 110 - fours;
304 }
305
306 return 0;
307 }
308
iguanair_set_tx_mask(struct rc_dev * dev,uint32_t mask)309 static int iguanair_set_tx_mask(struct rc_dev *dev, uint32_t mask)
310 {
311 struct iguanair *ir = dev->priv;
312
313 if (mask > 15)
314 return 4;
315
316 ir->packet->channels = mask << 4;
317
318 return 0;
319 }
320
iguanair_tx(struct rc_dev * dev,unsigned * txbuf,unsigned count)321 static int iguanair_tx(struct rc_dev *dev, unsigned *txbuf, unsigned count)
322 {
323 struct iguanair *ir = dev->priv;
324 unsigned int i, size, p, periods;
325 int rc;
326
327 /* convert from us to carrier periods */
328 for (i = size = 0; i < count; i++) {
329 periods = DIV_ROUND_CLOSEST(txbuf[i] * ir->carrier, 1000000);
330 while (periods) {
331 p = min(periods, 127u);
332 if (size >= ir->bufsize) {
333 rc = -EINVAL;
334 goto out;
335 }
336 ir->packet->payload[size++] = p | ((i & 1) ? 0x80 : 0);
337 periods -= p;
338 }
339 }
340
341 ir->packet->header.start = 0;
342 ir->packet->header.direction = DIR_OUT;
343 ir->packet->header.cmd = CMD_SEND;
344 ir->packet->length = size;
345
346 ir->tx_overflow = false;
347
348 rc = iguanair_send(ir, sizeof(*ir->packet) + size);
349
350 if (rc == 0 && ir->tx_overflow)
351 rc = -EOVERFLOW;
352
353 out:
354 return rc ? rc : count;
355 }
356
iguanair_open(struct rc_dev * rdev)357 static int iguanair_open(struct rc_dev *rdev)
358 {
359 struct iguanair *ir = rdev->priv;
360 int rc;
361
362 rc = iguanair_receiver(ir, true);
363 if (rc == 0)
364 ir->receiver_on = true;
365
366 return rc;
367 }
368
iguanair_close(struct rc_dev * rdev)369 static void iguanair_close(struct rc_dev *rdev)
370 {
371 struct iguanair *ir = rdev->priv;
372 int rc;
373
374 rc = iguanair_receiver(ir, false);
375 ir->receiver_on = false;
376 if (rc && rc != -ENODEV)
377 dev_warn(ir->dev, "failed to disable receiver: %d\n", rc);
378 }
379
iguanair_probe(struct usb_interface * intf,const struct usb_device_id * id)380 static int iguanair_probe(struct usb_interface *intf,
381 const struct usb_device_id *id)
382 {
383 struct usb_device *udev = interface_to_usbdev(intf);
384 struct iguanair *ir;
385 struct rc_dev *rc;
386 int ret, pipein, pipeout;
387 struct usb_host_interface *idesc;
388
389 idesc = intf->cur_altsetting;
390 if (idesc->desc.bNumEndpoints < 2)
391 return -ENODEV;
392
393 ir = kzalloc(sizeof(*ir), GFP_KERNEL);
394 rc = rc_allocate_device(RC_DRIVER_IR_RAW);
395 if (!ir || !rc) {
396 ret = -ENOMEM;
397 goto out;
398 }
399
400 ir->buf_in = usb_alloc_coherent(udev, MAX_IN_PACKET, GFP_KERNEL,
401 &ir->dma_in);
402 ir->packet = usb_alloc_coherent(udev, MAX_OUT_PACKET, GFP_KERNEL,
403 &ir->dma_out);
404 ir->urb_in = usb_alloc_urb(0, GFP_KERNEL);
405 ir->urb_out = usb_alloc_urb(0, GFP_KERNEL);
406
407 if (!ir->buf_in || !ir->packet || !ir->urb_in || !ir->urb_out ||
408 !usb_endpoint_is_int_in(&idesc->endpoint[0].desc) ||
409 !usb_endpoint_is_int_out(&idesc->endpoint[1].desc)) {
410 ret = -ENOMEM;
411 goto out;
412 }
413
414 ir->rc = rc;
415 ir->dev = &intf->dev;
416 ir->udev = udev;
417
418 init_completion(&ir->completion);
419 pipeout = usb_sndintpipe(udev,
420 idesc->endpoint[1].desc.bEndpointAddress);
421 usb_fill_int_urb(ir->urb_out, udev, pipeout, ir->packet, MAX_OUT_PACKET,
422 iguanair_irq_out, ir, 1);
423 ir->urb_out->transfer_dma = ir->dma_out;
424 ir->urb_out->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
425
426 pipein = usb_rcvintpipe(udev, idesc->endpoint[0].desc.bEndpointAddress);
427 usb_fill_int_urb(ir->urb_in, udev, pipein, ir->buf_in, MAX_IN_PACKET,
428 iguanair_rx, ir, 1);
429 ir->urb_in->transfer_dma = ir->dma_in;
430 ir->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
431
432 ret = usb_submit_urb(ir->urb_in, GFP_KERNEL);
433 if (ret) {
434 dev_warn(&intf->dev, "failed to submit urb: %d\n", ret);
435 goto out;
436 }
437
438 ret = iguanair_get_features(ir);
439 if (ret)
440 goto out2;
441
442 snprintf(ir->name, sizeof(ir->name),
443 "IguanaWorks USB IR Transceiver version 0x%04x", ir->version);
444
445 usb_make_path(ir->udev, ir->phys, sizeof(ir->phys));
446
447 rc->device_name = ir->name;
448 rc->input_phys = ir->phys;
449 usb_to_input_id(ir->udev, &rc->input_id);
450 rc->dev.parent = &intf->dev;
451 rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
452 rc->priv = ir;
453 rc->open = iguanair_open;
454 rc->close = iguanair_close;
455 rc->s_tx_mask = iguanair_set_tx_mask;
456 rc->s_tx_carrier = iguanair_set_tx_carrier;
457 rc->tx_ir = iguanair_tx;
458 rc->driver_name = KBUILD_MODNAME;
459 rc->map_name = RC_MAP_RC6_MCE;
460 rc->min_timeout = 1;
461 rc->timeout = IR_DEFAULT_TIMEOUT;
462 rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
463 rc->rx_resolution = RX_RESOLUTION;
464
465 iguanair_set_tx_carrier(rc, 38000);
466 iguanair_set_tx_mask(rc, 0);
467
468 ret = rc_register_device(rc);
469 if (ret < 0) {
470 dev_err(&intf->dev, "failed to register rc device %d", ret);
471 goto out2;
472 }
473
474 usb_set_intfdata(intf, ir);
475
476 return 0;
477 out2:
478 usb_kill_urb(ir->urb_in);
479 usb_kill_urb(ir->urb_out);
480 out:
481 if (ir) {
482 usb_free_urb(ir->urb_in);
483 usb_free_urb(ir->urb_out);
484 usb_free_coherent(udev, MAX_IN_PACKET, ir->buf_in, ir->dma_in);
485 usb_free_coherent(udev, MAX_OUT_PACKET, ir->packet,
486 ir->dma_out);
487 }
488 rc_free_device(rc);
489 kfree(ir);
490 return ret;
491 }
492
iguanair_disconnect(struct usb_interface * intf)493 static void iguanair_disconnect(struct usb_interface *intf)
494 {
495 struct iguanair *ir = usb_get_intfdata(intf);
496
497 rc_unregister_device(ir->rc);
498 usb_set_intfdata(intf, NULL);
499 usb_kill_urb(ir->urb_in);
500 usb_kill_urb(ir->urb_out);
501 usb_free_urb(ir->urb_in);
502 usb_free_urb(ir->urb_out);
503 usb_free_coherent(ir->udev, MAX_IN_PACKET, ir->buf_in, ir->dma_in);
504 usb_free_coherent(ir->udev, MAX_OUT_PACKET, ir->packet, ir->dma_out);
505 kfree(ir);
506 }
507
iguanair_suspend(struct usb_interface * intf,pm_message_t message)508 static int iguanair_suspend(struct usb_interface *intf, pm_message_t message)
509 {
510 struct iguanair *ir = usb_get_intfdata(intf);
511 int rc = 0;
512
513 if (ir->receiver_on) {
514 rc = iguanair_receiver(ir, false);
515 if (rc)
516 dev_warn(ir->dev, "failed to disable receiver for suspend\n");
517 }
518
519 usb_kill_urb(ir->urb_in);
520 usb_kill_urb(ir->urb_out);
521
522 return rc;
523 }
524
iguanair_resume(struct usb_interface * intf)525 static int iguanair_resume(struct usb_interface *intf)
526 {
527 struct iguanair *ir = usb_get_intfdata(intf);
528 int rc;
529
530 rc = usb_submit_urb(ir->urb_in, GFP_KERNEL);
531 if (rc)
532 dev_warn(&intf->dev, "failed to submit urb: %d\n", rc);
533
534 if (ir->receiver_on) {
535 rc = iguanair_receiver(ir, true);
536 if (rc)
537 dev_warn(ir->dev, "failed to enable receiver after resume\n");
538 }
539
540 return rc;
541 }
542
543 static const struct usb_device_id iguanair_table[] = {
544 { USB_DEVICE(0x1781, 0x0938) },
545 { }
546 };
547
548 static struct usb_driver iguanair_driver = {
549 .name = KBUILD_MODNAME,
550 .probe = iguanair_probe,
551 .disconnect = iguanair_disconnect,
552 .suspend = iguanair_suspend,
553 .resume = iguanair_resume,
554 .reset_resume = iguanair_resume,
555 .id_table = iguanair_table,
556 .soft_unbind = 1 /* we want to disable receiver on unbind */
557 };
558
559 module_usb_driver(iguanair_driver);
560
561 MODULE_DESCRIPTION("IguanaWorks USB IR Transceiver");
562 MODULE_AUTHOR("Sean Young <sean@mess.org>");
563 MODULE_LICENSE("GPL");
564 MODULE_DEVICE_TABLE(usb, iguanair_table);
565
566