xref: /openbmc/linux/drivers/media/rc/iguanair.c (revision 81de3bf3)
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 DRIVER_NAME "iguanair"
18 #define BUF_SIZE 152
19 
20 struct iguanair {
21 	struct rc_dev *rc;
22 
23 	struct device *dev;
24 	struct usb_device *udev;
25 
26 	uint16_t version;
27 	uint8_t bufsize;
28 	uint8_t cycle_overhead;
29 
30 	struct mutex lock;
31 
32 	/* receiver support */
33 	bool receiver_on;
34 	dma_addr_t dma_in, dma_out;
35 	uint8_t *buf_in;
36 	struct urb *urb_in, *urb_out;
37 	struct completion completion;
38 
39 	/* transmit support */
40 	bool tx_overflow;
41 	uint32_t carrier;
42 	struct send_packet *packet;
43 
44 	char name[64];
45 	char phys[64];
46 };
47 
48 #define CMD_NOP			0x00
49 #define CMD_GET_VERSION		0x01
50 #define CMD_GET_BUFSIZE		0x11
51 #define CMD_GET_FEATURES	0x10
52 #define CMD_SEND		0x15
53 #define CMD_EXECUTE		0x1f
54 #define CMD_RX_OVERFLOW		0x31
55 #define CMD_TX_OVERFLOW		0x32
56 #define CMD_RECEIVER_ON		0x12
57 #define CMD_RECEIVER_OFF	0x14
58 
59 #define DIR_IN			0xdc
60 #define DIR_OUT			0xcd
61 
62 #define MAX_IN_PACKET		8u
63 #define MAX_OUT_PACKET		(sizeof(struct send_packet) + BUF_SIZE)
64 #define TIMEOUT			1000
65 #define RX_RESOLUTION		21333
66 
67 struct packet {
68 	uint16_t start;
69 	uint8_t direction;
70 	uint8_t cmd;
71 };
72 
73 struct send_packet {
74 	struct packet header;
75 	uint8_t length;
76 	uint8_t channels;
77 	uint8_t busy7;
78 	uint8_t busy4;
79 	uint8_t payload[0];
80 };
81 
82 static void process_ir_data(struct iguanair *ir, unsigned len)
83 {
84 	if (len >= 4 && ir->buf_in[0] == 0 && ir->buf_in[1] == 0) {
85 		switch (ir->buf_in[3]) {
86 		case CMD_GET_VERSION:
87 			if (len == 6) {
88 				ir->version = (ir->buf_in[5] << 8) |
89 							ir->buf_in[4];
90 				complete(&ir->completion);
91 			}
92 			break;
93 		case CMD_GET_BUFSIZE:
94 			if (len >= 5) {
95 				ir->bufsize = ir->buf_in[4];
96 				complete(&ir->completion);
97 			}
98 			break;
99 		case CMD_GET_FEATURES:
100 			if (len > 5) {
101 				ir->cycle_overhead = ir->buf_in[5];
102 				complete(&ir->completion);
103 			}
104 			break;
105 		case CMD_TX_OVERFLOW:
106 			ir->tx_overflow = true;
107 			/* fall through */
108 		case CMD_RECEIVER_OFF:
109 		case CMD_RECEIVER_ON:
110 		case CMD_SEND:
111 			complete(&ir->completion);
112 			break;
113 		case CMD_RX_OVERFLOW:
114 			dev_warn(ir->dev, "receive overflow\n");
115 			ir_raw_event_reset(ir->rc);
116 			break;
117 		default:
118 			dev_warn(ir->dev, "control code %02x received\n",
119 							ir->buf_in[3]);
120 			break;
121 		}
122 	} else if (len >= 7) {
123 		struct ir_raw_event rawir = {};
124 		unsigned i;
125 		bool event = false;
126 
127 		for (i = 0; i < 7; i++) {
128 			if (ir->buf_in[i] == 0x80) {
129 				rawir.pulse = false;
130 				rawir.duration = US_TO_NS(21845);
131 			} else {
132 				rawir.pulse = (ir->buf_in[i] & 0x80) == 0;
133 				rawir.duration = ((ir->buf_in[i] & 0x7f) + 1) *
134 								 RX_RESOLUTION;
135 			}
136 
137 			if (ir_raw_event_store_with_filter(ir->rc, &rawir))
138 				event = true;
139 		}
140 
141 		if (event)
142 			ir_raw_event_handle(ir->rc);
143 	}
144 }
145 
146 static void iguanair_rx(struct urb *urb)
147 {
148 	struct iguanair *ir;
149 	int rc;
150 
151 	if (!urb)
152 		return;
153 
154 	ir = urb->context;
155 	if (!ir) {
156 		usb_unlink_urb(urb);
157 		return;
158 	}
159 
160 	switch (urb->status) {
161 	case 0:
162 		process_ir_data(ir, urb->actual_length);
163 		break;
164 	case -ECONNRESET:
165 	case -ENOENT:
166 	case -ESHUTDOWN:
167 		usb_unlink_urb(urb);
168 		return;
169 	case -EPIPE:
170 	default:
171 		dev_dbg(ir->dev, "Error: urb status = %d\n", urb->status);
172 		break;
173 	}
174 
175 	rc = usb_submit_urb(urb, GFP_ATOMIC);
176 	if (rc && rc != -ENODEV)
177 		dev_warn(ir->dev, "failed to resubmit urb: %d\n", rc);
178 }
179 
180 static void iguanair_irq_out(struct urb *urb)
181 {
182 	struct iguanair *ir = urb->context;
183 
184 	if (urb->status)
185 		dev_dbg(ir->dev, "Error: out urb status = %d\n", urb->status);
186 
187 	/* if we sent an nop packet, do not expect a response */
188 	if (urb->status == 0 && ir->packet->header.cmd == CMD_NOP)
189 		complete(&ir->completion);
190 }
191 
192 static int iguanair_send(struct iguanair *ir, unsigned size)
193 {
194 	int rc;
195 
196 	reinit_completion(&ir->completion);
197 
198 	ir->urb_out->transfer_buffer_length = size;
199 	rc = usb_submit_urb(ir->urb_out, GFP_KERNEL);
200 	if (rc)
201 		return rc;
202 
203 	if (wait_for_completion_timeout(&ir->completion, TIMEOUT) == 0)
204 		return -ETIMEDOUT;
205 
206 	return rc;
207 }
208 
209 static int iguanair_get_features(struct iguanair *ir)
210 {
211 	int rc;
212 
213 	/*
214 	 * On cold boot, the iguanair initializes on the first packet
215 	 * received but does not process that packet. Send an empty
216 	 * packet.
217 	 */
218 	ir->packet->header.start = 0;
219 	ir->packet->header.direction = DIR_OUT;
220 	ir->packet->header.cmd = CMD_NOP;
221 	iguanair_send(ir, sizeof(ir->packet->header));
222 
223 	ir->packet->header.cmd = CMD_GET_VERSION;
224 	rc = iguanair_send(ir, sizeof(ir->packet->header));
225 	if (rc) {
226 		dev_info(ir->dev, "failed to get version\n");
227 		goto out;
228 	}
229 
230 	if (ir->version < 0x205) {
231 		dev_err(ir->dev, "firmware 0x%04x is too old\n", ir->version);
232 		rc = -ENODEV;
233 		goto out;
234 	}
235 
236 	ir->bufsize = 150;
237 	ir->cycle_overhead = 65;
238 
239 	ir->packet->header.cmd = CMD_GET_BUFSIZE;
240 
241 	rc = iguanair_send(ir, sizeof(ir->packet->header));
242 	if (rc) {
243 		dev_info(ir->dev, "failed to get buffer size\n");
244 		goto out;
245 	}
246 
247 	if (ir->bufsize > BUF_SIZE) {
248 		dev_info(ir->dev, "buffer size %u larger than expected\n",
249 								ir->bufsize);
250 		ir->bufsize = BUF_SIZE;
251 	}
252 
253 	ir->packet->header.cmd = CMD_GET_FEATURES;
254 
255 	rc = iguanair_send(ir, sizeof(ir->packet->header));
256 	if (rc)
257 		dev_info(ir->dev, "failed to get features\n");
258 out:
259 	return rc;
260 }
261 
262 static int iguanair_receiver(struct iguanair *ir, bool enable)
263 {
264 	ir->packet->header.start = 0;
265 	ir->packet->header.direction = DIR_OUT;
266 	ir->packet->header.cmd = enable ? CMD_RECEIVER_ON : CMD_RECEIVER_OFF;
267 
268 	if (enable)
269 		ir_raw_event_reset(ir->rc);
270 
271 	return iguanair_send(ir, sizeof(ir->packet->header));
272 }
273 
274 /*
275  * The iguanair creates the carrier by busy spinning after each half period.
276  * This is counted in CPU cycles, with the CPU running at 24MHz. It is
277  * broken down into 7-cycles and 4-cyles delays, with a preference for
278  * 4-cycle delays, minus the overhead of the loop itself (cycle_overhead).
279  */
280 static int iguanair_set_tx_carrier(struct rc_dev *dev, uint32_t carrier)
281 {
282 	struct iguanair *ir = dev->priv;
283 
284 	if (carrier < 25000 || carrier > 150000)
285 		return -EINVAL;
286 
287 	mutex_lock(&ir->lock);
288 
289 	if (carrier != ir->carrier) {
290 		uint32_t cycles, fours, sevens;
291 
292 		ir->carrier = carrier;
293 
294 		cycles = DIV_ROUND_CLOSEST(24000000, carrier * 2) -
295 							ir->cycle_overhead;
296 
297 		/*
298 		 * Calculate minimum number of 7 cycles needed so
299 		 * we are left with a multiple of 4; so we want to have
300 		 * (sevens * 7) & 3 == cycles & 3
301 		 */
302 		sevens = (4 - cycles) & 3;
303 		fours = (cycles - sevens * 7) / 4;
304 
305 		/*
306 		 * The firmware interprets these values as a relative offset
307 		 * for a branch. Immediately following the branches, there
308 		 * 4 instructions of 7 cycles (2 bytes each) and 110
309 		 * instructions of 4 cycles (1 byte each). A relative branch
310 		 * of 0 will execute all of them, branch further for less
311 		 * cycle burning.
312 		 */
313 		ir->packet->busy7 = (4 - sevens) * 2;
314 		ir->packet->busy4 = 110 - fours;
315 	}
316 
317 	mutex_unlock(&ir->lock);
318 
319 	return 0;
320 }
321 
322 static int iguanair_set_tx_mask(struct rc_dev *dev, uint32_t mask)
323 {
324 	struct iguanair *ir = dev->priv;
325 
326 	if (mask > 15)
327 		return 4;
328 
329 	mutex_lock(&ir->lock);
330 	ir->packet->channels = mask << 4;
331 	mutex_unlock(&ir->lock);
332 
333 	return 0;
334 }
335 
336 static int iguanair_tx(struct rc_dev *dev, unsigned *txbuf, unsigned count)
337 {
338 	struct iguanair *ir = dev->priv;
339 	unsigned int i, size, p, periods;
340 	int rc;
341 
342 	mutex_lock(&ir->lock);
343 
344 	/* convert from us to carrier periods */
345 	for (i = size = 0; i < count; i++) {
346 		periods = DIV_ROUND_CLOSEST(txbuf[i] * ir->carrier, 1000000);
347 		while (periods) {
348 			p = min(periods, 127u);
349 			if (size >= ir->bufsize) {
350 				rc = -EINVAL;
351 				goto out;
352 			}
353 			ir->packet->payload[size++] = p | ((i & 1) ? 0x80 : 0);
354 			periods -= p;
355 		}
356 	}
357 
358 	ir->packet->header.start = 0;
359 	ir->packet->header.direction = DIR_OUT;
360 	ir->packet->header.cmd = CMD_SEND;
361 	ir->packet->length = size;
362 
363 	ir->tx_overflow = false;
364 
365 	rc = iguanair_send(ir, sizeof(*ir->packet) + size);
366 
367 	if (rc == 0 && ir->tx_overflow)
368 		rc = -EOVERFLOW;
369 
370 out:
371 	mutex_unlock(&ir->lock);
372 
373 	return rc ? rc : count;
374 }
375 
376 static int iguanair_open(struct rc_dev *rdev)
377 {
378 	struct iguanair *ir = rdev->priv;
379 	int rc;
380 
381 	mutex_lock(&ir->lock);
382 
383 	rc = iguanair_receiver(ir, true);
384 	if (rc == 0)
385 		ir->receiver_on = true;
386 
387 	mutex_unlock(&ir->lock);
388 
389 	return rc;
390 }
391 
392 static void iguanair_close(struct rc_dev *rdev)
393 {
394 	struct iguanair *ir = rdev->priv;
395 	int rc;
396 
397 	mutex_lock(&ir->lock);
398 
399 	rc = iguanair_receiver(ir, false);
400 	ir->receiver_on = false;
401 	if (rc && rc != -ENODEV)
402 		dev_warn(ir->dev, "failed to disable receiver: %d\n", rc);
403 
404 	mutex_unlock(&ir->lock);
405 }
406 
407 static int iguanair_probe(struct usb_interface *intf,
408 			  const struct usb_device_id *id)
409 {
410 	struct usb_device *udev = interface_to_usbdev(intf);
411 	struct iguanair *ir;
412 	struct rc_dev *rc;
413 	int ret, pipein, pipeout;
414 	struct usb_host_interface *idesc;
415 
416 	idesc = intf->altsetting;
417 	if (idesc->desc.bNumEndpoints < 2)
418 		return -ENODEV;
419 
420 	ir = kzalloc(sizeof(*ir), GFP_KERNEL);
421 	rc = rc_allocate_device(RC_DRIVER_IR_RAW);
422 	if (!ir || !rc) {
423 		ret = -ENOMEM;
424 		goto out;
425 	}
426 
427 	ir->buf_in = usb_alloc_coherent(udev, MAX_IN_PACKET, GFP_KERNEL,
428 								&ir->dma_in);
429 	ir->packet = usb_alloc_coherent(udev, MAX_OUT_PACKET, GFP_KERNEL,
430 								&ir->dma_out);
431 	ir->urb_in = usb_alloc_urb(0, GFP_KERNEL);
432 	ir->urb_out = usb_alloc_urb(0, GFP_KERNEL);
433 
434 	if (!ir->buf_in || !ir->packet || !ir->urb_in || !ir->urb_out ||
435 	    !usb_endpoint_is_int_in(&idesc->endpoint[0].desc) ||
436 	    !usb_endpoint_is_int_out(&idesc->endpoint[1].desc)) {
437 		ret = -ENOMEM;
438 		goto out;
439 	}
440 
441 	ir->rc = rc;
442 	ir->dev = &intf->dev;
443 	ir->udev = udev;
444 	mutex_init(&ir->lock);
445 
446 	init_completion(&ir->completion);
447 	pipeout = usb_sndintpipe(udev,
448 				idesc->endpoint[1].desc.bEndpointAddress);
449 	usb_fill_int_urb(ir->urb_out, udev, pipeout, ir->packet, MAX_OUT_PACKET,
450 						iguanair_irq_out, ir, 1);
451 	ir->urb_out->transfer_dma = ir->dma_out;
452 	ir->urb_out->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
453 
454 	pipein = usb_rcvintpipe(udev, idesc->endpoint[0].desc.bEndpointAddress);
455 	usb_fill_int_urb(ir->urb_in, udev, pipein, ir->buf_in, MAX_IN_PACKET,
456 							 iguanair_rx, ir, 1);
457 	ir->urb_in->transfer_dma = ir->dma_in;
458 	ir->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
459 
460 	ret = usb_submit_urb(ir->urb_in, GFP_KERNEL);
461 	if (ret) {
462 		dev_warn(&intf->dev, "failed to submit urb: %d\n", ret);
463 		goto out;
464 	}
465 
466 	ret = iguanair_get_features(ir);
467 	if (ret)
468 		goto out2;
469 
470 	snprintf(ir->name, sizeof(ir->name),
471 		"IguanaWorks USB IR Transceiver version 0x%04x", ir->version);
472 
473 	usb_make_path(ir->udev, ir->phys, sizeof(ir->phys));
474 
475 	rc->device_name = ir->name;
476 	rc->input_phys = ir->phys;
477 	usb_to_input_id(ir->udev, &rc->input_id);
478 	rc->dev.parent = &intf->dev;
479 	rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
480 	rc->priv = ir;
481 	rc->open = iguanair_open;
482 	rc->close = iguanair_close;
483 	rc->s_tx_mask = iguanair_set_tx_mask;
484 	rc->s_tx_carrier = iguanair_set_tx_carrier;
485 	rc->tx_ir = iguanair_tx;
486 	rc->driver_name = DRIVER_NAME;
487 	rc->map_name = RC_MAP_RC6_MCE;
488 	rc->min_timeout = 1;
489 	rc->timeout = IR_DEFAULT_TIMEOUT;
490 	rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
491 	rc->rx_resolution = RX_RESOLUTION;
492 
493 	iguanair_set_tx_carrier(rc, 38000);
494 	iguanair_set_tx_mask(rc, 0);
495 
496 	ret = rc_register_device(rc);
497 	if (ret < 0) {
498 		dev_err(&intf->dev, "failed to register rc device %d", ret);
499 		goto out2;
500 	}
501 
502 	usb_set_intfdata(intf, ir);
503 
504 	return 0;
505 out2:
506 	usb_kill_urb(ir->urb_in);
507 	usb_kill_urb(ir->urb_out);
508 out:
509 	if (ir) {
510 		usb_free_urb(ir->urb_in);
511 		usb_free_urb(ir->urb_out);
512 		usb_free_coherent(udev, MAX_IN_PACKET, ir->buf_in, ir->dma_in);
513 		usb_free_coherent(udev, MAX_OUT_PACKET, ir->packet,
514 								ir->dma_out);
515 	}
516 	rc_free_device(rc);
517 	kfree(ir);
518 	return ret;
519 }
520 
521 static void iguanair_disconnect(struct usb_interface *intf)
522 {
523 	struct iguanair *ir = usb_get_intfdata(intf);
524 
525 	rc_unregister_device(ir->rc);
526 	usb_set_intfdata(intf, NULL);
527 	usb_kill_urb(ir->urb_in);
528 	usb_kill_urb(ir->urb_out);
529 	usb_free_urb(ir->urb_in);
530 	usb_free_urb(ir->urb_out);
531 	usb_free_coherent(ir->udev, MAX_IN_PACKET, ir->buf_in, ir->dma_in);
532 	usb_free_coherent(ir->udev, MAX_OUT_PACKET, ir->packet, ir->dma_out);
533 	kfree(ir);
534 }
535 
536 static int iguanair_suspend(struct usb_interface *intf, pm_message_t message)
537 {
538 	struct iguanair *ir = usb_get_intfdata(intf);
539 	int rc = 0;
540 
541 	mutex_lock(&ir->lock);
542 
543 	if (ir->receiver_on) {
544 		rc = iguanair_receiver(ir, false);
545 		if (rc)
546 			dev_warn(ir->dev, "failed to disable receiver for suspend\n");
547 	}
548 
549 	usb_kill_urb(ir->urb_in);
550 	usb_kill_urb(ir->urb_out);
551 
552 	mutex_unlock(&ir->lock);
553 
554 	return rc;
555 }
556 
557 static int iguanair_resume(struct usb_interface *intf)
558 {
559 	struct iguanair *ir = usb_get_intfdata(intf);
560 	int rc = 0;
561 
562 	mutex_lock(&ir->lock);
563 
564 	rc = usb_submit_urb(ir->urb_in, GFP_KERNEL);
565 	if (rc)
566 		dev_warn(&intf->dev, "failed to submit urb: %d\n", rc);
567 
568 	if (ir->receiver_on) {
569 		rc = iguanair_receiver(ir, true);
570 		if (rc)
571 			dev_warn(ir->dev, "failed to enable receiver after resume\n");
572 	}
573 
574 	mutex_unlock(&ir->lock);
575 
576 	return rc;
577 }
578 
579 static const struct usb_device_id iguanair_table[] = {
580 	{ USB_DEVICE(0x1781, 0x0938) },
581 	{ }
582 };
583 
584 static struct usb_driver iguanair_driver = {
585 	.name =	DRIVER_NAME,
586 	.probe = iguanair_probe,
587 	.disconnect = iguanair_disconnect,
588 	.suspend = iguanair_suspend,
589 	.resume = iguanair_resume,
590 	.reset_resume = iguanair_resume,
591 	.id_table = iguanair_table,
592 	.soft_unbind = 1	/* we want to disable receiver on unbind */
593 };
594 
595 module_usb_driver(iguanair_driver);
596 
597 MODULE_DESCRIPTION("IguanaWorks USB IR Transceiver");
598 MODULE_AUTHOR("Sean Young <sean@mess.org>");
599 MODULE_LICENSE("GPL");
600 MODULE_DEVICE_TABLE(usb, iguanair_table);
601 
602