xref: /linux/drivers/media/rc/iguanair.c (revision bcb63314e2c23f1ed622418b65f9409512659c73)
1 /*
2  * IguanaWorks USB IR Transceiver support
3  *
4  * Copyright (C) 2012 Sean Young <sean@mess.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #include <linux/device.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/usb.h>
21 #include <linux/usb/input.h>
22 #include <linux/slab.h>
23 #include <linux/completion.h>
24 #include <media/rc-core.h>
25 
26 #define DRIVER_NAME "iguanair"
27 #define BUF_SIZE 152
28 
29 struct iguanair {
30 	struct rc_dev *rc;
31 
32 	struct device *dev;
33 	struct usb_device *udev;
34 
35 	uint16_t version;
36 	uint8_t bufsize;
37 	uint8_t cycle_overhead;
38 
39 	struct mutex lock;
40 
41 	/* receiver support */
42 	bool receiver_on;
43 	dma_addr_t dma_in, dma_out;
44 	uint8_t *buf_in;
45 	struct urb *urb_in, *urb_out;
46 	struct completion completion;
47 
48 	/* transmit support */
49 	bool tx_overflow;
50 	uint32_t carrier;
51 	struct send_packet *packet;
52 
53 	char name[64];
54 	char phys[64];
55 };
56 
57 #define CMD_NOP			0x00
58 #define CMD_GET_VERSION		0x01
59 #define CMD_GET_BUFSIZE		0x11
60 #define CMD_GET_FEATURES	0x10
61 #define CMD_SEND		0x15
62 #define CMD_EXECUTE		0x1f
63 #define CMD_RX_OVERFLOW		0x31
64 #define CMD_TX_OVERFLOW		0x32
65 #define CMD_RECEIVER_ON		0x12
66 #define CMD_RECEIVER_OFF	0x14
67 
68 #define DIR_IN			0xdc
69 #define DIR_OUT			0xcd
70 
71 #define MAX_IN_PACKET		8u
72 #define MAX_OUT_PACKET		(sizeof(struct send_packet) + BUF_SIZE)
73 #define TIMEOUT			1000
74 #define RX_RESOLUTION		21333
75 
76 struct packet {
77 	uint16_t start;
78 	uint8_t direction;
79 	uint8_t cmd;
80 };
81 
82 struct send_packet {
83 	struct packet header;
84 	uint8_t length;
85 	uint8_t channels;
86 	uint8_t busy7;
87 	uint8_t busy4;
88 	uint8_t payload[0];
89 };
90 
91 static void process_ir_data(struct iguanair *ir, unsigned len)
92 {
93 	if (len >= 4 && ir->buf_in[0] == 0 && ir->buf_in[1] == 0) {
94 		switch (ir->buf_in[3]) {
95 		case CMD_GET_VERSION:
96 			if (len == 6) {
97 				ir->version = (ir->buf_in[5] << 8) |
98 							ir->buf_in[4];
99 				complete(&ir->completion);
100 			}
101 			break;
102 		case CMD_GET_BUFSIZE:
103 			if (len >= 5) {
104 				ir->bufsize = ir->buf_in[4];
105 				complete(&ir->completion);
106 			}
107 			break;
108 		case CMD_GET_FEATURES:
109 			if (len > 5) {
110 				ir->cycle_overhead = ir->buf_in[5];
111 				complete(&ir->completion);
112 			}
113 			break;
114 		case CMD_TX_OVERFLOW:
115 			ir->tx_overflow = true;
116 		case CMD_RECEIVER_OFF:
117 		case CMD_RECEIVER_ON:
118 		case CMD_SEND:
119 			complete(&ir->completion);
120 			break;
121 		case CMD_RX_OVERFLOW:
122 			dev_warn(ir->dev, "receive overflow\n");
123 			ir_raw_event_reset(ir->rc);
124 			break;
125 		default:
126 			dev_warn(ir->dev, "control code %02x received\n",
127 							ir->buf_in[3]);
128 			break;
129 		}
130 	} else if (len >= 7) {
131 		DEFINE_IR_RAW_EVENT(rawir);
132 		unsigned i;
133 		bool event = false;
134 
135 		init_ir_raw_event(&rawir);
136 
137 		for (i = 0; i < 7; i++) {
138 			if (ir->buf_in[i] == 0x80) {
139 				rawir.pulse = false;
140 				rawir.duration = US_TO_NS(21845);
141 			} else {
142 				rawir.pulse = (ir->buf_in[i] & 0x80) == 0;
143 				rawir.duration = ((ir->buf_in[i] & 0x7f) + 1) *
144 								 RX_RESOLUTION;
145 			}
146 
147 			if (ir_raw_event_store_with_filter(ir->rc, &rawir))
148 				event = true;
149 		}
150 
151 		if (event)
152 			ir_raw_event_handle(ir->rc);
153 	}
154 }
155 
156 static void iguanair_rx(struct urb *urb)
157 {
158 	struct iguanair *ir;
159 	int rc;
160 
161 	if (!urb)
162 		return;
163 
164 	ir = urb->context;
165 	if (!ir) {
166 		usb_unlink_urb(urb);
167 		return;
168 	}
169 
170 	switch (urb->status) {
171 	case 0:
172 		process_ir_data(ir, urb->actual_length);
173 		break;
174 	case -ECONNRESET:
175 	case -ENOENT:
176 	case -ESHUTDOWN:
177 		usb_unlink_urb(urb);
178 		return;
179 	case -EPIPE:
180 	default:
181 		dev_dbg(ir->dev, "Error: urb status = %d\n", urb->status);
182 		break;
183 	}
184 
185 	rc = usb_submit_urb(urb, GFP_ATOMIC);
186 	if (rc && rc != -ENODEV)
187 		dev_warn(ir->dev, "failed to resubmit urb: %d\n", rc);
188 }
189 
190 static void iguanair_irq_out(struct urb *urb)
191 {
192 	struct iguanair *ir = urb->context;
193 
194 	if (urb->status)
195 		dev_dbg(ir->dev, "Error: out urb status = %d\n", urb->status);
196 
197 	/* if we sent an nop packet, do not expect a response */
198 	if (urb->status == 0 && ir->packet->header.cmd == CMD_NOP)
199 		complete(&ir->completion);
200 }
201 
202 static int iguanair_send(struct iguanair *ir, unsigned size)
203 {
204 	int rc;
205 
206 	reinit_completion(&ir->completion);
207 
208 	ir->urb_out->transfer_buffer_length = size;
209 	rc = usb_submit_urb(ir->urb_out, GFP_KERNEL);
210 	if (rc)
211 		return rc;
212 
213 	if (wait_for_completion_timeout(&ir->completion, TIMEOUT) == 0)
214 		return -ETIMEDOUT;
215 
216 	return rc;
217 }
218 
219 static int iguanair_get_features(struct iguanair *ir)
220 {
221 	int rc;
222 
223 	/*
224 	 * On cold boot, the iguanair initializes on the first packet
225 	 * received but does not process that packet. Send an empty
226 	 * packet.
227 	 */
228 	ir->packet->header.start = 0;
229 	ir->packet->header.direction = DIR_OUT;
230 	ir->packet->header.cmd = CMD_NOP;
231 	iguanair_send(ir, sizeof(ir->packet->header));
232 
233 	ir->packet->header.cmd = CMD_GET_VERSION;
234 	rc = iguanair_send(ir, sizeof(ir->packet->header));
235 	if (rc) {
236 		dev_info(ir->dev, "failed to get version\n");
237 		goto out;
238 	}
239 
240 	if (ir->version < 0x205) {
241 		dev_err(ir->dev, "firmware 0x%04x is too old\n", ir->version);
242 		rc = -ENODEV;
243 		goto out;
244 	}
245 
246 	ir->bufsize = 150;
247 	ir->cycle_overhead = 65;
248 
249 	ir->packet->header.cmd = CMD_GET_BUFSIZE;
250 
251 	rc = iguanair_send(ir, sizeof(ir->packet->header));
252 	if (rc) {
253 		dev_info(ir->dev, "failed to get buffer size\n");
254 		goto out;
255 	}
256 
257 	if (ir->bufsize > BUF_SIZE) {
258 		dev_info(ir->dev, "buffer size %u larger than expected\n",
259 								ir->bufsize);
260 		ir->bufsize = BUF_SIZE;
261 	}
262 
263 	ir->packet->header.cmd = CMD_GET_FEATURES;
264 
265 	rc = iguanair_send(ir, sizeof(ir->packet->header));
266 	if (rc)
267 		dev_info(ir->dev, "failed to get features\n");
268 out:
269 	return rc;
270 }
271 
272 static int iguanair_receiver(struct iguanair *ir, bool enable)
273 {
274 	ir->packet->header.start = 0;
275 	ir->packet->header.direction = DIR_OUT;
276 	ir->packet->header.cmd = enable ? CMD_RECEIVER_ON : CMD_RECEIVER_OFF;
277 
278 	if (enable)
279 		ir_raw_event_reset(ir->rc);
280 
281 	return iguanair_send(ir, sizeof(ir->packet->header));
282 }
283 
284 /*
285  * The iguanair creates the carrier by busy spinning after each half period.
286  * This is counted in CPU cycles, with the CPU running at 24MHz. It is
287  * broken down into 7-cycles and 4-cyles delays, with a preference for
288  * 4-cycle delays, minus the overhead of the loop itself (cycle_overhead).
289  */
290 static int iguanair_set_tx_carrier(struct rc_dev *dev, uint32_t carrier)
291 {
292 	struct iguanair *ir = dev->priv;
293 
294 	if (carrier < 25000 || carrier > 150000)
295 		return -EINVAL;
296 
297 	mutex_lock(&ir->lock);
298 
299 	if (carrier != ir->carrier) {
300 		uint32_t cycles, fours, sevens;
301 
302 		ir->carrier = carrier;
303 
304 		cycles = DIV_ROUND_CLOSEST(24000000, carrier * 2) -
305 							ir->cycle_overhead;
306 
307 		/*
308 		 * Calculate minimum number of 7 cycles needed so
309 		 * we are left with a multiple of 4; so we want to have
310 		 * (sevens * 7) & 3 == cycles & 3
311 		 */
312 		sevens = (4 - cycles) & 3;
313 		fours = (cycles - sevens * 7) / 4;
314 
315 		/*
316 		 * The firmware interprets these values as a relative offset
317 		 * for a branch. Immediately following the branches, there
318 		 * 4 instructions of 7 cycles (2 bytes each) and 110
319 		 * instructions of 4 cycles (1 byte each). A relative branch
320 		 * of 0 will execute all of them, branch further for less
321 		 * cycle burning.
322 		 */
323 		ir->packet->busy7 = (4 - sevens) * 2;
324 		ir->packet->busy4 = 110 - fours;
325 	}
326 
327 	mutex_unlock(&ir->lock);
328 
329 	return 0;
330 }
331 
332 static int iguanair_set_tx_mask(struct rc_dev *dev, uint32_t mask)
333 {
334 	struct iguanair *ir = dev->priv;
335 
336 	if (mask > 15)
337 		return 4;
338 
339 	mutex_lock(&ir->lock);
340 	ir->packet->channels = mask << 4;
341 	mutex_unlock(&ir->lock);
342 
343 	return 0;
344 }
345 
346 static int iguanair_tx(struct rc_dev *dev, unsigned *txbuf, unsigned count)
347 {
348 	struct iguanair *ir = dev->priv;
349 	uint8_t space;
350 	unsigned i, size, periods, bytes;
351 	int rc;
352 
353 	mutex_lock(&ir->lock);
354 
355 	/* convert from us to carrier periods */
356 	for (i = space = size = 0; i < count; i++) {
357 		periods = DIV_ROUND_CLOSEST(txbuf[i] * ir->carrier, 1000000);
358 		bytes = DIV_ROUND_UP(periods, 127);
359 		if (size + bytes > ir->bufsize) {
360 			rc = -EINVAL;
361 			goto out;
362 		}
363 		while (periods) {
364 			unsigned p = min(periods, 127u);
365 			ir->packet->payload[size++] = p | space;
366 			periods -= p;
367 		}
368 		space ^= 0x80;
369 	}
370 
371 	ir->packet->header.start = 0;
372 	ir->packet->header.direction = DIR_OUT;
373 	ir->packet->header.cmd = CMD_SEND;
374 	ir->packet->length = size;
375 
376 	ir->tx_overflow = false;
377 
378 	rc = iguanair_send(ir, sizeof(*ir->packet) + size);
379 
380 	if (rc == 0 && ir->tx_overflow)
381 		rc = -EOVERFLOW;
382 
383 out:
384 	mutex_unlock(&ir->lock);
385 
386 	return rc ? rc : count;
387 }
388 
389 static int iguanair_open(struct rc_dev *rdev)
390 {
391 	struct iguanair *ir = rdev->priv;
392 	int rc;
393 
394 	mutex_lock(&ir->lock);
395 
396 	rc = iguanair_receiver(ir, true);
397 	if (rc == 0)
398 		ir->receiver_on = true;
399 
400 	mutex_unlock(&ir->lock);
401 
402 	return rc;
403 }
404 
405 static void iguanair_close(struct rc_dev *rdev)
406 {
407 	struct iguanair *ir = rdev->priv;
408 	int rc;
409 
410 	mutex_lock(&ir->lock);
411 
412 	rc = iguanair_receiver(ir, false);
413 	ir->receiver_on = false;
414 	if (rc && rc != -ENODEV)
415 		dev_warn(ir->dev, "failed to disable receiver: %d\n", rc);
416 
417 	mutex_unlock(&ir->lock);
418 }
419 
420 static int iguanair_probe(struct usb_interface *intf,
421 			  const struct usb_device_id *id)
422 {
423 	struct usb_device *udev = interface_to_usbdev(intf);
424 	struct iguanair *ir;
425 	struct rc_dev *rc;
426 	int ret, pipein, pipeout;
427 	struct usb_host_interface *idesc;
428 
429 	ir = kzalloc(sizeof(*ir), GFP_KERNEL);
430 	rc = rc_allocate_device();
431 	if (!ir || !rc) {
432 		ret = -ENOMEM;
433 		goto out;
434 	}
435 
436 	ir->buf_in = usb_alloc_coherent(udev, MAX_IN_PACKET, GFP_KERNEL,
437 								&ir->dma_in);
438 	ir->packet = usb_alloc_coherent(udev, MAX_OUT_PACKET, GFP_KERNEL,
439 								&ir->dma_out);
440 	ir->urb_in = usb_alloc_urb(0, GFP_KERNEL);
441 	ir->urb_out = usb_alloc_urb(0, GFP_KERNEL);
442 
443 	if (!ir->buf_in || !ir->packet || !ir->urb_in || !ir->urb_out) {
444 		ret = -ENOMEM;
445 		goto out;
446 	}
447 
448 	idesc = intf->altsetting;
449 
450 	if (idesc->desc.bNumEndpoints < 2) {
451 		ret = -ENODEV;
452 		goto out;
453 	}
454 
455 	ir->rc = rc;
456 	ir->dev = &intf->dev;
457 	ir->udev = udev;
458 	mutex_init(&ir->lock);
459 
460 	init_completion(&ir->completion);
461 	pipeout = usb_sndintpipe(udev,
462 				idesc->endpoint[1].desc.bEndpointAddress);
463 	usb_fill_int_urb(ir->urb_out, udev, pipeout, ir->packet, MAX_OUT_PACKET,
464 						iguanair_irq_out, ir, 1);
465 	ir->urb_out->transfer_dma = ir->dma_out;
466 	ir->urb_out->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
467 
468 	pipein = usb_rcvintpipe(udev, idesc->endpoint[0].desc.bEndpointAddress);
469 	usb_fill_int_urb(ir->urb_in, udev, pipein, ir->buf_in, MAX_IN_PACKET,
470 							 iguanair_rx, ir, 1);
471 	ir->urb_in->transfer_dma = ir->dma_in;
472 	ir->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
473 
474 	ret = usb_submit_urb(ir->urb_in, GFP_KERNEL);
475 	if (ret) {
476 		dev_warn(&intf->dev, "failed to submit urb: %d\n", ret);
477 		goto out;
478 	}
479 
480 	ret = iguanair_get_features(ir);
481 	if (ret)
482 		goto out2;
483 
484 	snprintf(ir->name, sizeof(ir->name),
485 		"IguanaWorks USB IR Transceiver version 0x%04x", ir->version);
486 
487 	usb_make_path(ir->udev, ir->phys, sizeof(ir->phys));
488 
489 	rc->input_name = ir->name;
490 	rc->input_phys = ir->phys;
491 	usb_to_input_id(ir->udev, &rc->input_id);
492 	rc->dev.parent = &intf->dev;
493 	rc->driver_type = RC_DRIVER_IR_RAW;
494 	rc->allowed_protocols = RC_BIT_ALL;
495 	rc->priv = ir;
496 	rc->open = iguanair_open;
497 	rc->close = iguanair_close;
498 	rc->s_tx_mask = iguanair_set_tx_mask;
499 	rc->s_tx_carrier = iguanair_set_tx_carrier;
500 	rc->tx_ir = iguanair_tx;
501 	rc->driver_name = DRIVER_NAME;
502 	rc->map_name = RC_MAP_RC6_MCE;
503 	rc->timeout = MS_TO_NS(100);
504 	rc->rx_resolution = RX_RESOLUTION;
505 
506 	iguanair_set_tx_carrier(rc, 38000);
507 	iguanair_set_tx_mask(rc, 0);
508 
509 	ret = rc_register_device(rc);
510 	if (ret < 0) {
511 		dev_err(&intf->dev, "failed to register rc device %d", ret);
512 		goto out2;
513 	}
514 
515 	usb_set_intfdata(intf, ir);
516 
517 	return 0;
518 out2:
519 	usb_kill_urb(ir->urb_in);
520 	usb_kill_urb(ir->urb_out);
521 out:
522 	if (ir) {
523 		usb_free_urb(ir->urb_in);
524 		usb_free_urb(ir->urb_out);
525 		usb_free_coherent(udev, MAX_IN_PACKET, ir->buf_in, ir->dma_in);
526 		usb_free_coherent(udev, MAX_OUT_PACKET, ir->packet,
527 								ir->dma_out);
528 	}
529 	rc_free_device(rc);
530 	kfree(ir);
531 	return ret;
532 }
533 
534 static void iguanair_disconnect(struct usb_interface *intf)
535 {
536 	struct iguanair *ir = usb_get_intfdata(intf);
537 
538 	rc_unregister_device(ir->rc);
539 	usb_set_intfdata(intf, NULL);
540 	usb_kill_urb(ir->urb_in);
541 	usb_kill_urb(ir->urb_out);
542 	usb_free_urb(ir->urb_in);
543 	usb_free_urb(ir->urb_out);
544 	usb_free_coherent(ir->udev, MAX_IN_PACKET, ir->buf_in, ir->dma_in);
545 	usb_free_coherent(ir->udev, MAX_OUT_PACKET, ir->packet, ir->dma_out);
546 	kfree(ir);
547 }
548 
549 static int iguanair_suspend(struct usb_interface *intf, pm_message_t message)
550 {
551 	struct iguanair *ir = usb_get_intfdata(intf);
552 	int rc = 0;
553 
554 	mutex_lock(&ir->lock);
555 
556 	if (ir->receiver_on) {
557 		rc = iguanair_receiver(ir, false);
558 		if (rc)
559 			dev_warn(ir->dev, "failed to disable receiver for suspend\n");
560 	}
561 
562 	usb_kill_urb(ir->urb_in);
563 	usb_kill_urb(ir->urb_out);
564 
565 	mutex_unlock(&ir->lock);
566 
567 	return rc;
568 }
569 
570 static int iguanair_resume(struct usb_interface *intf)
571 {
572 	struct iguanair *ir = usb_get_intfdata(intf);
573 	int rc = 0;
574 
575 	mutex_lock(&ir->lock);
576 
577 	rc = usb_submit_urb(ir->urb_in, GFP_KERNEL);
578 	if (rc)
579 		dev_warn(&intf->dev, "failed to submit urb: %d\n", rc);
580 
581 	if (ir->receiver_on) {
582 		rc = iguanair_receiver(ir, true);
583 		if (rc)
584 			dev_warn(ir->dev, "failed to enable receiver after resume\n");
585 	}
586 
587 	mutex_unlock(&ir->lock);
588 
589 	return rc;
590 }
591 
592 static const struct usb_device_id iguanair_table[] = {
593 	{ USB_DEVICE(0x1781, 0x0938) },
594 	{ }
595 };
596 
597 static struct usb_driver iguanair_driver = {
598 	.name =	DRIVER_NAME,
599 	.probe = iguanair_probe,
600 	.disconnect = iguanair_disconnect,
601 	.suspend = iguanair_suspend,
602 	.resume = iguanair_resume,
603 	.reset_resume = iguanair_resume,
604 	.id_table = iguanair_table,
605 	.soft_unbind = 1	/* we want to disable receiver on unbind */
606 };
607 
608 module_usb_driver(iguanair_driver);
609 
610 MODULE_DESCRIPTION("IguanaWorks USB IR Transceiver");
611 MODULE_AUTHOR("Sean Young <sean@mess.org>");
612 MODULE_LICENSE("GPL");
613 MODULE_DEVICE_TABLE(usb, iguanair_table);
614 
615