xref: /openbmc/linux/drivers/media/rc/lirc_dev.c (revision 94d964e5)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * LIRC base driver
4  *
5  * by Artur Lipowski <alipowski@interia.pl>
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/module.h>
11 #include <linux/mutex.h>
12 #include <linux/device.h>
13 #include <linux/file.h>
14 #include <linux/idr.h>
15 #include <linux/poll.h>
16 #include <linux/sched.h>
17 #include <linux/wait.h>
18 
19 #include "rc-core-priv.h"
20 #include <uapi/linux/lirc.h>
21 
22 #define LIRCBUF_SIZE	1024
23 
24 static dev_t lirc_base_dev;
25 
26 /* Used to keep track of allocated lirc devices */
27 static DEFINE_IDA(lirc_ida);
28 
29 /* Only used for sysfs but defined to void otherwise */
30 static struct class *lirc_class;
31 
32 /**
33  * lirc_raw_event() - Send raw IR data to lirc to be relayed to userspace
34  *
35  * @dev:	the struct rc_dev descriptor of the device
36  * @ev:		the struct ir_raw_event descriptor of the pulse/space
37  */
38 void lirc_raw_event(struct rc_dev *dev, struct ir_raw_event ev)
39 {
40 	unsigned long flags;
41 	struct lirc_fh *fh;
42 	int sample;
43 
44 	/* Packet start */
45 	if (ev.reset) {
46 		/*
47 		 * Userspace expects a long space event before the start of
48 		 * the signal to use as a sync.  This may be done with repeat
49 		 * packets and normal samples.  But if a reset has been sent
50 		 * then we assume that a long time has passed, so we send a
51 		 * space with the maximum time value.
52 		 */
53 		sample = LIRC_SPACE(LIRC_VALUE_MASK);
54 		dev_dbg(&dev->dev, "delivering reset sync space to lirc_dev\n");
55 
56 	/* Carrier reports */
57 	} else if (ev.carrier_report) {
58 		sample = LIRC_FREQUENCY(ev.carrier);
59 		dev_dbg(&dev->dev, "carrier report (freq: %d)\n", sample);
60 
61 	/* Packet end */
62 	} else if (ev.timeout) {
63 		dev->gap_start = ktime_get();
64 
65 		sample = LIRC_TIMEOUT(ev.duration);
66 		dev_dbg(&dev->dev, "timeout report (duration: %d)\n", sample);
67 
68 	/* Normal sample */
69 	} else {
70 		if (dev->gap_start) {
71 			u64 duration = ktime_us_delta(ktime_get(),
72 						      dev->gap_start);
73 
74 			/* Cap by LIRC_VALUE_MASK */
75 			duration = min_t(u64, duration, LIRC_VALUE_MASK);
76 
77 			spin_lock_irqsave(&dev->lirc_fh_lock, flags);
78 			list_for_each_entry(fh, &dev->lirc_fh, list)
79 				kfifo_put(&fh->rawir, LIRC_SPACE(duration));
80 			spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
81 			dev->gap_start = 0;
82 		}
83 
84 		sample = ev.pulse ? LIRC_PULSE(ev.duration) :
85 					LIRC_SPACE(ev.duration);
86 		dev_dbg(&dev->dev, "delivering %uus %s to lirc_dev\n",
87 			ev.duration, TO_STR(ev.pulse));
88 	}
89 
90 	/*
91 	 * bpf does not care about the gap generated above; that exists
92 	 * for backwards compatibility
93 	 */
94 	lirc_bpf_run(dev, sample);
95 
96 	spin_lock_irqsave(&dev->lirc_fh_lock, flags);
97 	list_for_each_entry(fh, &dev->lirc_fh, list) {
98 		if (kfifo_put(&fh->rawir, sample))
99 			wake_up_poll(&fh->wait_poll, EPOLLIN | EPOLLRDNORM);
100 	}
101 	spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
102 }
103 
104 /**
105  * lirc_scancode_event() - Send scancode data to lirc to be relayed to
106  *		userspace. This can be called in atomic context.
107  * @dev:	the struct rc_dev descriptor of the device
108  * @lsc:	the struct lirc_scancode describing the decoded scancode
109  */
110 void lirc_scancode_event(struct rc_dev *dev, struct lirc_scancode *lsc)
111 {
112 	unsigned long flags;
113 	struct lirc_fh *fh;
114 
115 	lsc->timestamp = ktime_get_ns();
116 
117 	spin_lock_irqsave(&dev->lirc_fh_lock, flags);
118 	list_for_each_entry(fh, &dev->lirc_fh, list) {
119 		if (kfifo_put(&fh->scancodes, *lsc))
120 			wake_up_poll(&fh->wait_poll, EPOLLIN | EPOLLRDNORM);
121 	}
122 	spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
123 }
124 EXPORT_SYMBOL_GPL(lirc_scancode_event);
125 
126 static int lirc_open(struct inode *inode, struct file *file)
127 {
128 	struct rc_dev *dev = container_of(inode->i_cdev, struct rc_dev,
129 					  lirc_cdev);
130 	struct lirc_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL);
131 	unsigned long flags;
132 	int retval;
133 
134 	if (!fh)
135 		return -ENOMEM;
136 
137 	get_device(&dev->dev);
138 
139 	if (!dev->registered) {
140 		retval = -ENODEV;
141 		goto out_fh;
142 	}
143 
144 	if (dev->driver_type == RC_DRIVER_IR_RAW) {
145 		if (kfifo_alloc(&fh->rawir, MAX_IR_EVENT_SIZE, GFP_KERNEL)) {
146 			retval = -ENOMEM;
147 			goto out_fh;
148 		}
149 	}
150 
151 	if (dev->driver_type != RC_DRIVER_IR_RAW_TX) {
152 		if (kfifo_alloc(&fh->scancodes, 32, GFP_KERNEL)) {
153 			retval = -ENOMEM;
154 			goto out_rawir;
155 		}
156 	}
157 
158 	fh->send_mode = LIRC_MODE_PULSE;
159 	fh->rc = dev;
160 
161 	if (dev->driver_type == RC_DRIVER_SCANCODE)
162 		fh->rec_mode = LIRC_MODE_SCANCODE;
163 	else
164 		fh->rec_mode = LIRC_MODE_MODE2;
165 
166 	retval = rc_open(dev);
167 	if (retval)
168 		goto out_kfifo;
169 
170 	init_waitqueue_head(&fh->wait_poll);
171 
172 	file->private_data = fh;
173 	spin_lock_irqsave(&dev->lirc_fh_lock, flags);
174 	list_add(&fh->list, &dev->lirc_fh);
175 	spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
176 
177 	stream_open(inode, file);
178 
179 	return 0;
180 out_kfifo:
181 	if (dev->driver_type != RC_DRIVER_IR_RAW_TX)
182 		kfifo_free(&fh->scancodes);
183 out_rawir:
184 	if (dev->driver_type == RC_DRIVER_IR_RAW)
185 		kfifo_free(&fh->rawir);
186 out_fh:
187 	kfree(fh);
188 	put_device(&dev->dev);
189 
190 	return retval;
191 }
192 
193 static int lirc_close(struct inode *inode, struct file *file)
194 {
195 	struct lirc_fh *fh = file->private_data;
196 	struct rc_dev *dev = fh->rc;
197 	unsigned long flags;
198 
199 	spin_lock_irqsave(&dev->lirc_fh_lock, flags);
200 	list_del(&fh->list);
201 	spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
202 
203 	if (dev->driver_type == RC_DRIVER_IR_RAW)
204 		kfifo_free(&fh->rawir);
205 	if (dev->driver_type != RC_DRIVER_IR_RAW_TX)
206 		kfifo_free(&fh->scancodes);
207 	kfree(fh);
208 
209 	rc_close(dev);
210 	put_device(&dev->dev);
211 
212 	return 0;
213 }
214 
215 static ssize_t lirc_transmit(struct file *file, const char __user *buf,
216 			     size_t n, loff_t *ppos)
217 {
218 	struct lirc_fh *fh = file->private_data;
219 	struct rc_dev *dev = fh->rc;
220 	unsigned int *txbuf;
221 	struct ir_raw_event *raw = NULL;
222 	ssize_t ret;
223 	size_t count;
224 	ktime_t start;
225 	s64 towait;
226 	unsigned int duration = 0; /* signal duration in us */
227 	int i;
228 
229 	ret = mutex_lock_interruptible(&dev->lock);
230 	if (ret)
231 		return ret;
232 
233 	if (!dev->registered) {
234 		ret = -ENODEV;
235 		goto out_unlock;
236 	}
237 
238 	if (!dev->tx_ir) {
239 		ret = -EINVAL;
240 		goto out_unlock;
241 	}
242 
243 	if (fh->send_mode == LIRC_MODE_SCANCODE) {
244 		struct lirc_scancode scan;
245 
246 		if (n != sizeof(scan)) {
247 			ret = -EINVAL;
248 			goto out_unlock;
249 		}
250 
251 		if (copy_from_user(&scan, buf, sizeof(scan))) {
252 			ret = -EFAULT;
253 			goto out_unlock;
254 		}
255 
256 		if (scan.flags || scan.keycode || scan.timestamp ||
257 		    scan.rc_proto > RC_PROTO_MAX) {
258 			ret = -EINVAL;
259 			goto out_unlock;
260 		}
261 
262 		/* We only have encoders for 32-bit protocols. */
263 		if (scan.scancode > U32_MAX ||
264 		    !rc_validate_scancode(scan.rc_proto, scan.scancode)) {
265 			ret = -EINVAL;
266 			goto out_unlock;
267 		}
268 
269 		raw = kmalloc_array(LIRCBUF_SIZE, sizeof(*raw), GFP_KERNEL);
270 		if (!raw) {
271 			ret = -ENOMEM;
272 			goto out_unlock;
273 		}
274 
275 		ret = ir_raw_encode_scancode(scan.rc_proto, scan.scancode,
276 					     raw, LIRCBUF_SIZE);
277 		if (ret < 0)
278 			goto out_kfree_raw;
279 
280 		count = ret;
281 
282 		txbuf = kmalloc_array(count, sizeof(unsigned int), GFP_KERNEL);
283 		if (!txbuf) {
284 			ret = -ENOMEM;
285 			goto out_kfree_raw;
286 		}
287 
288 		for (i = 0; i < count; i++)
289 			txbuf[i] = raw[i].duration;
290 
291 		if (dev->s_tx_carrier) {
292 			int carrier = ir_raw_encode_carrier(scan.rc_proto);
293 
294 			if (carrier > 0)
295 				dev->s_tx_carrier(dev, carrier);
296 		}
297 	} else {
298 		if (n < sizeof(unsigned int) || n % sizeof(unsigned int)) {
299 			ret = -EINVAL;
300 			goto out_unlock;
301 		}
302 
303 		count = n / sizeof(unsigned int);
304 		if (count > LIRCBUF_SIZE || count % 2 == 0) {
305 			ret = -EINVAL;
306 			goto out_unlock;
307 		}
308 
309 		txbuf = memdup_user(buf, n);
310 		if (IS_ERR(txbuf)) {
311 			ret = PTR_ERR(txbuf);
312 			goto out_unlock;
313 		}
314 	}
315 
316 	for (i = 0; i < count; i++) {
317 		if (txbuf[i] > IR_MAX_DURATION - duration || !txbuf[i]) {
318 			ret = -EINVAL;
319 			goto out_kfree;
320 		}
321 
322 		duration += txbuf[i];
323 	}
324 
325 	start = ktime_get();
326 
327 	ret = dev->tx_ir(dev, txbuf, count);
328 	if (ret < 0)
329 		goto out_kfree;
330 
331 	kfree(txbuf);
332 	kfree(raw);
333 	mutex_unlock(&dev->lock);
334 
335 	/*
336 	 * The lircd gap calculation expects the write function to
337 	 * wait for the actual IR signal to be transmitted before
338 	 * returning.
339 	 */
340 	towait = ktime_us_delta(ktime_add_us(start, duration),
341 				ktime_get());
342 	if (towait > 0) {
343 		set_current_state(TASK_INTERRUPTIBLE);
344 		schedule_timeout(usecs_to_jiffies(towait));
345 	}
346 
347 	return n;
348 out_kfree:
349 	kfree(txbuf);
350 out_kfree_raw:
351 	kfree(raw);
352 out_unlock:
353 	mutex_unlock(&dev->lock);
354 	return ret;
355 }
356 
357 static long lirc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
358 {
359 	struct lirc_fh *fh = file->private_data;
360 	struct rc_dev *dev = fh->rc;
361 	u32 __user *argp = (u32 __user *)(arg);
362 	u32 val = 0;
363 	int ret;
364 
365 	if (_IOC_DIR(cmd) & _IOC_WRITE) {
366 		ret = get_user(val, argp);
367 		if (ret)
368 			return ret;
369 	}
370 
371 	ret = mutex_lock_interruptible(&dev->lock);
372 	if (ret)
373 		return ret;
374 
375 	if (!dev->registered) {
376 		ret = -ENODEV;
377 		goto out;
378 	}
379 
380 	switch (cmd) {
381 	case LIRC_GET_FEATURES:
382 		if (dev->driver_type == RC_DRIVER_SCANCODE)
383 			val |= LIRC_CAN_REC_SCANCODE;
384 
385 		if (dev->driver_type == RC_DRIVER_IR_RAW) {
386 			val |= LIRC_CAN_REC_MODE2;
387 			if (dev->rx_resolution)
388 				val |= LIRC_CAN_GET_REC_RESOLUTION;
389 		}
390 
391 		if (dev->tx_ir) {
392 			val |= LIRC_CAN_SEND_PULSE;
393 			if (dev->s_tx_mask)
394 				val |= LIRC_CAN_SET_TRANSMITTER_MASK;
395 			if (dev->s_tx_carrier)
396 				val |= LIRC_CAN_SET_SEND_CARRIER;
397 			if (dev->s_tx_duty_cycle)
398 				val |= LIRC_CAN_SET_SEND_DUTY_CYCLE;
399 		}
400 
401 		if (dev->s_rx_carrier_range)
402 			val |= LIRC_CAN_SET_REC_CARRIER |
403 				LIRC_CAN_SET_REC_CARRIER_RANGE;
404 
405 		if (dev->s_wideband_receiver)
406 			val |= LIRC_CAN_USE_WIDEBAND_RECEIVER;
407 
408 		if (dev->s_carrier_report)
409 			val |= LIRC_CAN_MEASURE_CARRIER;
410 
411 		if (dev->max_timeout)
412 			val |= LIRC_CAN_SET_REC_TIMEOUT;
413 
414 		break;
415 
416 	/* mode support */
417 	case LIRC_GET_REC_MODE:
418 		if (dev->driver_type == RC_DRIVER_IR_RAW_TX)
419 			ret = -ENOTTY;
420 		else
421 			val = fh->rec_mode;
422 		break;
423 
424 	case LIRC_SET_REC_MODE:
425 		switch (dev->driver_type) {
426 		case RC_DRIVER_IR_RAW_TX:
427 			ret = -ENOTTY;
428 			break;
429 		case RC_DRIVER_SCANCODE:
430 			if (val != LIRC_MODE_SCANCODE)
431 				ret = -EINVAL;
432 			break;
433 		case RC_DRIVER_IR_RAW:
434 			if (!(val == LIRC_MODE_MODE2 ||
435 			      val == LIRC_MODE_SCANCODE))
436 				ret = -EINVAL;
437 			break;
438 		}
439 
440 		if (!ret)
441 			fh->rec_mode = val;
442 		break;
443 
444 	case LIRC_GET_SEND_MODE:
445 		if (!dev->tx_ir)
446 			ret = -ENOTTY;
447 		else
448 			val = fh->send_mode;
449 		break;
450 
451 	case LIRC_SET_SEND_MODE:
452 		if (!dev->tx_ir)
453 			ret = -ENOTTY;
454 		else if (!(val == LIRC_MODE_PULSE || val == LIRC_MODE_SCANCODE))
455 			ret = -EINVAL;
456 		else
457 			fh->send_mode = val;
458 		break;
459 
460 	/* TX settings */
461 	case LIRC_SET_TRANSMITTER_MASK:
462 		if (!dev->s_tx_mask)
463 			ret = -ENOTTY;
464 		else
465 			ret = dev->s_tx_mask(dev, val);
466 		break;
467 
468 	case LIRC_SET_SEND_CARRIER:
469 		if (!dev->s_tx_carrier)
470 			ret = -ENOTTY;
471 		else
472 			ret = dev->s_tx_carrier(dev, val);
473 		break;
474 
475 	case LIRC_SET_SEND_DUTY_CYCLE:
476 		if (!dev->s_tx_duty_cycle)
477 			ret = -ENOTTY;
478 		else if (val <= 0 || val >= 100)
479 			ret = -EINVAL;
480 		else
481 			ret = dev->s_tx_duty_cycle(dev, val);
482 		break;
483 
484 	/* RX settings */
485 	case LIRC_SET_REC_CARRIER:
486 		if (!dev->s_rx_carrier_range)
487 			ret = -ENOTTY;
488 		else if (val <= 0)
489 			ret = -EINVAL;
490 		else
491 			ret = dev->s_rx_carrier_range(dev, fh->carrier_low,
492 						      val);
493 		break;
494 
495 	case LIRC_SET_REC_CARRIER_RANGE:
496 		if (!dev->s_rx_carrier_range)
497 			ret = -ENOTTY;
498 		else if (val <= 0)
499 			ret = -EINVAL;
500 		else
501 			fh->carrier_low = val;
502 		break;
503 
504 	case LIRC_GET_REC_RESOLUTION:
505 		if (!dev->rx_resolution)
506 			ret = -ENOTTY;
507 		else
508 			val = dev->rx_resolution;
509 		break;
510 
511 	case LIRC_SET_WIDEBAND_RECEIVER:
512 		if (!dev->s_wideband_receiver)
513 			ret = -ENOTTY;
514 		else
515 			ret = dev->s_wideband_receiver(dev, !!val);
516 		break;
517 
518 	case LIRC_SET_MEASURE_CARRIER_MODE:
519 		if (!dev->s_carrier_report)
520 			ret = -ENOTTY;
521 		else
522 			ret = dev->s_carrier_report(dev, !!val);
523 		break;
524 
525 	/* Generic timeout support */
526 	case LIRC_GET_MIN_TIMEOUT:
527 		if (!dev->max_timeout)
528 			ret = -ENOTTY;
529 		else
530 			val = dev->min_timeout;
531 		break;
532 
533 	case LIRC_GET_MAX_TIMEOUT:
534 		if (!dev->max_timeout)
535 			ret = -ENOTTY;
536 		else
537 			val = dev->max_timeout;
538 		break;
539 
540 	case LIRC_SET_REC_TIMEOUT:
541 		if (!dev->max_timeout) {
542 			ret = -ENOTTY;
543 		} else {
544 			if (val < dev->min_timeout || val > dev->max_timeout)
545 				ret = -EINVAL;
546 			else if (dev->s_timeout)
547 				ret = dev->s_timeout(dev, val);
548 			else
549 				dev->timeout = val;
550 		}
551 		break;
552 
553 	case LIRC_GET_REC_TIMEOUT:
554 		if (!dev->timeout)
555 			ret = -ENOTTY;
556 		else
557 			val = dev->timeout;
558 		break;
559 
560 	case LIRC_SET_REC_TIMEOUT_REPORTS:
561 		if (dev->driver_type != RC_DRIVER_IR_RAW)
562 			ret = -ENOTTY;
563 		break;
564 
565 	default:
566 		ret = -ENOTTY;
567 	}
568 
569 	if (!ret && _IOC_DIR(cmd) & _IOC_READ)
570 		ret = put_user(val, argp);
571 
572 out:
573 	mutex_unlock(&dev->lock);
574 	return ret;
575 }
576 
577 static __poll_t lirc_poll(struct file *file, struct poll_table_struct *wait)
578 {
579 	struct lirc_fh *fh = file->private_data;
580 	struct rc_dev *rcdev = fh->rc;
581 	__poll_t events = 0;
582 
583 	poll_wait(file, &fh->wait_poll, wait);
584 
585 	if (!rcdev->registered) {
586 		events = EPOLLHUP | EPOLLERR;
587 	} else if (rcdev->driver_type != RC_DRIVER_IR_RAW_TX) {
588 		if (fh->rec_mode == LIRC_MODE_SCANCODE &&
589 		    !kfifo_is_empty(&fh->scancodes))
590 			events = EPOLLIN | EPOLLRDNORM;
591 
592 		if (fh->rec_mode == LIRC_MODE_MODE2 &&
593 		    !kfifo_is_empty(&fh->rawir))
594 			events = EPOLLIN | EPOLLRDNORM;
595 	}
596 
597 	return events;
598 }
599 
600 static ssize_t lirc_read_mode2(struct file *file, char __user *buffer,
601 			       size_t length)
602 {
603 	struct lirc_fh *fh = file->private_data;
604 	struct rc_dev *rcdev = fh->rc;
605 	unsigned int copied;
606 	int ret;
607 
608 	if (length < sizeof(unsigned int) || length % sizeof(unsigned int))
609 		return -EINVAL;
610 
611 	do {
612 		if (kfifo_is_empty(&fh->rawir)) {
613 			if (file->f_flags & O_NONBLOCK)
614 				return -EAGAIN;
615 
616 			ret = wait_event_interruptible(fh->wait_poll,
617 					!kfifo_is_empty(&fh->rawir) ||
618 					!rcdev->registered);
619 			if (ret)
620 				return ret;
621 		}
622 
623 		if (!rcdev->registered)
624 			return -ENODEV;
625 
626 		ret = mutex_lock_interruptible(&rcdev->lock);
627 		if (ret)
628 			return ret;
629 		ret = kfifo_to_user(&fh->rawir, buffer, length, &copied);
630 		mutex_unlock(&rcdev->lock);
631 		if (ret)
632 			return ret;
633 	} while (copied == 0);
634 
635 	return copied;
636 }
637 
638 static ssize_t lirc_read_scancode(struct file *file, char __user *buffer,
639 				  size_t length)
640 {
641 	struct lirc_fh *fh = file->private_data;
642 	struct rc_dev *rcdev = fh->rc;
643 	unsigned int copied;
644 	int ret;
645 
646 	if (length < sizeof(struct lirc_scancode) ||
647 	    length % sizeof(struct lirc_scancode))
648 		return -EINVAL;
649 
650 	do {
651 		if (kfifo_is_empty(&fh->scancodes)) {
652 			if (file->f_flags & O_NONBLOCK)
653 				return -EAGAIN;
654 
655 			ret = wait_event_interruptible(fh->wait_poll,
656 					!kfifo_is_empty(&fh->scancodes) ||
657 					!rcdev->registered);
658 			if (ret)
659 				return ret;
660 		}
661 
662 		if (!rcdev->registered)
663 			return -ENODEV;
664 
665 		ret = mutex_lock_interruptible(&rcdev->lock);
666 		if (ret)
667 			return ret;
668 		ret = kfifo_to_user(&fh->scancodes, buffer, length, &copied);
669 		mutex_unlock(&rcdev->lock);
670 		if (ret)
671 			return ret;
672 	} while (copied == 0);
673 
674 	return copied;
675 }
676 
677 static ssize_t lirc_read(struct file *file, char __user *buffer, size_t length,
678 			 loff_t *ppos)
679 {
680 	struct lirc_fh *fh = file->private_data;
681 	struct rc_dev *rcdev = fh->rc;
682 
683 	if (rcdev->driver_type == RC_DRIVER_IR_RAW_TX)
684 		return -EINVAL;
685 
686 	if (!rcdev->registered)
687 		return -ENODEV;
688 
689 	if (fh->rec_mode == LIRC_MODE_MODE2)
690 		return lirc_read_mode2(file, buffer, length);
691 	else /* LIRC_MODE_SCANCODE */
692 		return lirc_read_scancode(file, buffer, length);
693 }
694 
695 static const struct file_operations lirc_fops = {
696 	.owner		= THIS_MODULE,
697 	.write		= lirc_transmit,
698 	.unlocked_ioctl	= lirc_ioctl,
699 	.compat_ioctl	= compat_ptr_ioctl,
700 	.read		= lirc_read,
701 	.poll		= lirc_poll,
702 	.open		= lirc_open,
703 	.release	= lirc_close,
704 	.llseek		= no_llseek,
705 };
706 
707 static void lirc_release_device(struct device *ld)
708 {
709 	struct rc_dev *rcdev = container_of(ld, struct rc_dev, lirc_dev);
710 
711 	put_device(&rcdev->dev);
712 }
713 
714 int lirc_register(struct rc_dev *dev)
715 {
716 	const char *rx_type, *tx_type;
717 	int err, minor;
718 
719 	minor = ida_simple_get(&lirc_ida, 0, RC_DEV_MAX, GFP_KERNEL);
720 	if (minor < 0)
721 		return minor;
722 
723 	device_initialize(&dev->lirc_dev);
724 	dev->lirc_dev.class = lirc_class;
725 	dev->lirc_dev.parent = &dev->dev;
726 	dev->lirc_dev.release = lirc_release_device;
727 	dev->lirc_dev.devt = MKDEV(MAJOR(lirc_base_dev), minor);
728 	dev_set_name(&dev->lirc_dev, "lirc%d", minor);
729 
730 	INIT_LIST_HEAD(&dev->lirc_fh);
731 	spin_lock_init(&dev->lirc_fh_lock);
732 
733 	cdev_init(&dev->lirc_cdev, &lirc_fops);
734 
735 	err = cdev_device_add(&dev->lirc_cdev, &dev->lirc_dev);
736 	if (err)
737 		goto out_ida;
738 
739 	get_device(&dev->dev);
740 
741 	switch (dev->driver_type) {
742 	case RC_DRIVER_SCANCODE:
743 		rx_type = "scancode";
744 		break;
745 	case RC_DRIVER_IR_RAW:
746 		rx_type = "raw IR";
747 		break;
748 	default:
749 		rx_type = "no";
750 		break;
751 	}
752 
753 	if (dev->tx_ir)
754 		tx_type = "raw IR";
755 	else
756 		tx_type = "no";
757 
758 	dev_info(&dev->dev, "lirc_dev: driver %s registered at minor = %d, %s receiver, %s transmitter",
759 		 dev->driver_name, minor, rx_type, tx_type);
760 
761 	return 0;
762 
763 out_ida:
764 	ida_simple_remove(&lirc_ida, minor);
765 	return err;
766 }
767 
768 void lirc_unregister(struct rc_dev *dev)
769 {
770 	unsigned long flags;
771 	struct lirc_fh *fh;
772 
773 	dev_dbg(&dev->dev, "lirc_dev: driver %s unregistered from minor = %d\n",
774 		dev->driver_name, MINOR(dev->lirc_dev.devt));
775 
776 	spin_lock_irqsave(&dev->lirc_fh_lock, flags);
777 	list_for_each_entry(fh, &dev->lirc_fh, list)
778 		wake_up_poll(&fh->wait_poll, EPOLLHUP | EPOLLERR);
779 	spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
780 
781 	cdev_device_del(&dev->lirc_cdev, &dev->lirc_dev);
782 	ida_simple_remove(&lirc_ida, MINOR(dev->lirc_dev.devt));
783 }
784 
785 int __init lirc_dev_init(void)
786 {
787 	int retval;
788 
789 	lirc_class = class_create(THIS_MODULE, "lirc");
790 	if (IS_ERR(lirc_class)) {
791 		pr_err("class_create failed\n");
792 		return PTR_ERR(lirc_class);
793 	}
794 
795 	retval = alloc_chrdev_region(&lirc_base_dev, 0, RC_DEV_MAX, "lirc");
796 	if (retval) {
797 		class_destroy(lirc_class);
798 		pr_err("alloc_chrdev_region failed\n");
799 		return retval;
800 	}
801 
802 	pr_debug("IR Remote Control driver registered, major %d\n",
803 		 MAJOR(lirc_base_dev));
804 
805 	return 0;
806 }
807 
808 void __exit lirc_dev_exit(void)
809 {
810 	class_destroy(lirc_class);
811 	unregister_chrdev_region(lirc_base_dev, RC_DEV_MAX);
812 }
813 
814 struct rc_dev *rc_dev_get_from_fd(int fd)
815 {
816 	struct fd f = fdget(fd);
817 	struct lirc_fh *fh;
818 	struct rc_dev *dev;
819 
820 	if (!f.file)
821 		return ERR_PTR(-EBADF);
822 
823 	if (f.file->f_op != &lirc_fops) {
824 		fdput(f);
825 		return ERR_PTR(-EINVAL);
826 	}
827 
828 	fh = f.file->private_data;
829 	dev = fh->rc;
830 
831 	get_device(&dev->dev);
832 	fdput(f);
833 
834 	return dev;
835 }
836 
837 MODULE_ALIAS("lirc_dev");
838