xref: /linux/drivers/media/rc/lirc_dev.c (revision 906fd46a65383cd639e5eec72a047efc33045d86)
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 const struct class lirc_class = {
31 	.name = "lirc",
32 };
33 
34 /**
35  * lirc_raw_event() - Send raw IR data to lirc to be relayed to userspace
36  *
37  * @dev:	the struct rc_dev descriptor of the device
38  * @ev:		the struct ir_raw_event descriptor of the pulse/space
39  */
40 void lirc_raw_event(struct rc_dev *dev, struct ir_raw_event ev)
41 {
42 	unsigned long flags;
43 	struct lirc_fh *fh;
44 	int sample;
45 
46 	/* Receiver overflow, data missing */
47 	if (ev.overflow) {
48 		/*
49 		 * Send lirc overflow message. This message is unknown to
50 		 * lircd, but it will interpret this as a long space as
51 		 * long as the value is set to high value. This resets its
52 		 * decoder state.
53 		 */
54 		sample = LIRC_OVERFLOW(LIRC_VALUE_MASK);
55 		dev_dbg(&dev->dev, "delivering overflow to lirc_dev\n");
56 
57 	/* Carrier reports */
58 	} else if (ev.carrier_report) {
59 		sample = LIRC_FREQUENCY(ev.carrier);
60 		dev_dbg(&dev->dev, "carrier report (freq: %d)\n", sample);
61 
62 	/* Packet end */
63 	} else if (ev.timeout) {
64 		dev->gap_start = ktime_get();
65 
66 		sample = LIRC_TIMEOUT(ev.duration);
67 		dev_dbg(&dev->dev, "timeout report (duration: %d)\n", sample);
68 
69 	/* Normal sample */
70 	} else {
71 		if (dev->gap_start) {
72 			u64 duration = ktime_us_delta(ktime_get(),
73 						      dev->gap_start);
74 
75 			/* Cap by LIRC_VALUE_MASK */
76 			duration = min_t(u64, duration, LIRC_VALUE_MASK);
77 
78 			spin_lock_irqsave(&dev->lirc_fh_lock, flags);
79 			list_for_each_entry(fh, &dev->lirc_fh, list)
80 				kfifo_put(&fh->rawir, LIRC_SPACE(duration));
81 			spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
82 			dev->gap_start = 0;
83 		}
84 
85 		sample = ev.pulse ? LIRC_PULSE(ev.duration) :
86 					LIRC_SPACE(ev.duration);
87 		dev_dbg(&dev->dev, "delivering %uus %s to lirc_dev\n",
88 			ev.duration, TO_STR(ev.pulse));
89 	}
90 
91 	/*
92 	 * bpf does not care about the gap generated above; that exists
93 	 * for backwards compatibility
94 	 */
95 	lirc_bpf_run(dev, sample);
96 
97 	spin_lock_irqsave(&dev->lirc_fh_lock, flags);
98 	list_for_each_entry(fh, &dev->lirc_fh, list) {
99 		if (kfifo_put(&fh->rawir, sample))
100 			wake_up_poll(&fh->wait_poll, EPOLLIN | EPOLLRDNORM);
101 	}
102 	spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
103 }
104 
105 /**
106  * lirc_scancode_event() - Send scancode data to lirc to be relayed to
107  *		userspace. This can be called in atomic context.
108  * @dev:	the struct rc_dev descriptor of the device
109  * @lsc:	the struct lirc_scancode describing the decoded scancode
110  */
111 void lirc_scancode_event(struct rc_dev *dev, struct lirc_scancode *lsc)
112 {
113 	unsigned long flags;
114 	struct lirc_fh *fh;
115 
116 	lsc->timestamp = ktime_get_ns();
117 
118 	spin_lock_irqsave(&dev->lirc_fh_lock, flags);
119 	list_for_each_entry(fh, &dev->lirc_fh, list) {
120 		if (kfifo_put(&fh->scancodes, *lsc))
121 			wake_up_poll(&fh->wait_poll, EPOLLIN | EPOLLRDNORM);
122 	}
123 	spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
124 }
125 EXPORT_SYMBOL_GPL(lirc_scancode_event);
126 
127 static int lirc_open(struct inode *inode, struct file *file)
128 {
129 	struct rc_dev *dev = container_of(inode->i_cdev, struct rc_dev,
130 					  lirc_cdev);
131 	struct lirc_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL);
132 	unsigned long flags;
133 	int retval;
134 
135 	if (!fh)
136 		return -ENOMEM;
137 
138 	get_device(&dev->dev);
139 
140 	if (!dev->registered) {
141 		retval = -ENODEV;
142 		goto out_fh;
143 	}
144 
145 	if (dev->driver_type == RC_DRIVER_IR_RAW) {
146 		if (kfifo_alloc(&fh->rawir, MAX_IR_EVENT_SIZE, GFP_KERNEL)) {
147 			retval = -ENOMEM;
148 			goto out_fh;
149 		}
150 	}
151 
152 	if (dev->driver_type != RC_DRIVER_IR_RAW_TX) {
153 		if (kfifo_alloc(&fh->scancodes, 32, GFP_KERNEL)) {
154 			retval = -ENOMEM;
155 			goto out_rawir;
156 		}
157 	}
158 
159 	fh->send_mode = LIRC_MODE_PULSE;
160 	fh->rc = dev;
161 
162 	if (dev->driver_type == RC_DRIVER_SCANCODE)
163 		fh->rec_mode = LIRC_MODE_SCANCODE;
164 	else
165 		fh->rec_mode = LIRC_MODE_MODE2;
166 
167 	retval = rc_open(dev);
168 	if (retval)
169 		goto out_kfifo;
170 
171 	init_waitqueue_head(&fh->wait_poll);
172 
173 	file->private_data = fh;
174 	spin_lock_irqsave(&dev->lirc_fh_lock, flags);
175 	list_add(&fh->list, &dev->lirc_fh);
176 	spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
177 
178 	stream_open(inode, file);
179 
180 	return 0;
181 out_kfifo:
182 	if (dev->driver_type != RC_DRIVER_IR_RAW_TX)
183 		kfifo_free(&fh->scancodes);
184 out_rawir:
185 	if (dev->driver_type == RC_DRIVER_IR_RAW)
186 		kfifo_free(&fh->rawir);
187 out_fh:
188 	kfree(fh);
189 	put_device(&dev->dev);
190 
191 	return retval;
192 }
193 
194 static int lirc_close(struct inode *inode, struct file *file)
195 {
196 	struct lirc_fh *fh = file->private_data;
197 	struct rc_dev *dev = fh->rc;
198 	unsigned long flags;
199 
200 	spin_lock_irqsave(&dev->lirc_fh_lock, flags);
201 	list_del(&fh->list);
202 	spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
203 
204 	if (dev->driver_type == RC_DRIVER_IR_RAW)
205 		kfifo_free(&fh->rawir);
206 	if (dev->driver_type != RC_DRIVER_IR_RAW_TX)
207 		kfifo_free(&fh->scancodes);
208 	kfree(fh);
209 
210 	rc_close(dev);
211 	put_device(&dev->dev);
212 
213 	return 0;
214 }
215 
216 static ssize_t lirc_transmit(struct file *file, const char __user *buf,
217 			     size_t n, loff_t *ppos)
218 {
219 	struct lirc_fh *fh = file->private_data;
220 	struct rc_dev *dev = fh->rc;
221 	unsigned int *txbuf;
222 	struct ir_raw_event *raw = NULL;
223 	ssize_t ret;
224 	size_t count;
225 	ktime_t start;
226 	s64 towait;
227 	unsigned int duration = 0; /* signal duration in us */
228 	int i;
229 
230 	ret = mutex_lock_interruptible(&dev->lock);
231 	if (ret)
232 		return ret;
233 
234 	if (!dev->registered) {
235 		ret = -ENODEV;
236 		goto out_unlock;
237 	}
238 
239 	if (!dev->tx_ir) {
240 		ret = -EINVAL;
241 		goto out_unlock;
242 	}
243 
244 	if (fh->send_mode == LIRC_MODE_SCANCODE) {
245 		struct lirc_scancode scan;
246 
247 		if (n != sizeof(scan)) {
248 			ret = -EINVAL;
249 			goto out_unlock;
250 		}
251 
252 		if (copy_from_user(&scan, buf, sizeof(scan))) {
253 			ret = -EFAULT;
254 			goto out_unlock;
255 		}
256 
257 		if (scan.flags || scan.keycode || scan.timestamp ||
258 		    scan.rc_proto > RC_PROTO_MAX) {
259 			ret = -EINVAL;
260 			goto out_unlock;
261 		}
262 
263 		/* We only have encoders for 32-bit protocols. */
264 		if (scan.scancode > U32_MAX ||
265 		    !rc_validate_scancode(scan.rc_proto, scan.scancode)) {
266 			ret = -EINVAL;
267 			goto out_unlock;
268 		}
269 
270 		raw = kmalloc_array(LIRCBUF_SIZE, sizeof(*raw), GFP_KERNEL);
271 		if (!raw) {
272 			ret = -ENOMEM;
273 			goto out_unlock;
274 		}
275 
276 		ret = ir_raw_encode_scancode(scan.rc_proto, scan.scancode,
277 					     raw, LIRCBUF_SIZE);
278 		if (ret < 0)
279 			goto out_kfree_raw;
280 
281 		/* drop trailing space */
282 		if (!(ret % 2))
283 			count = ret - 1;
284 		else
285 			count = ret;
286 
287 		txbuf = kmalloc_array(count, sizeof(unsigned int), GFP_KERNEL);
288 		if (!txbuf) {
289 			ret = -ENOMEM;
290 			goto out_kfree_raw;
291 		}
292 
293 		for (i = 0; i < count; i++)
294 			txbuf[i] = raw[i].duration;
295 
296 		if (dev->s_tx_carrier) {
297 			int carrier = ir_raw_encode_carrier(scan.rc_proto);
298 
299 			if (carrier > 0)
300 				dev->s_tx_carrier(dev, carrier);
301 		}
302 	} else {
303 		if (n < sizeof(unsigned int) || n % sizeof(unsigned int)) {
304 			ret = -EINVAL;
305 			goto out_unlock;
306 		}
307 
308 		count = n / sizeof(unsigned int);
309 		if (count > LIRCBUF_SIZE || count % 2 == 0) {
310 			ret = -EINVAL;
311 			goto out_unlock;
312 		}
313 
314 		txbuf = memdup_user(buf, n);
315 		if (IS_ERR(txbuf)) {
316 			ret = PTR_ERR(txbuf);
317 			goto out_unlock;
318 		}
319 	}
320 
321 	for (i = 0; i < count; i++) {
322 		if (txbuf[i] > IR_MAX_DURATION - duration || !txbuf[i]) {
323 			ret = -EINVAL;
324 			goto out_kfree;
325 		}
326 
327 		duration += txbuf[i];
328 	}
329 
330 	start = ktime_get();
331 
332 	ret = dev->tx_ir(dev, txbuf, count);
333 	if (ret < 0)
334 		goto out_kfree;
335 
336 	kfree(txbuf);
337 	kfree(raw);
338 	mutex_unlock(&dev->lock);
339 
340 	/*
341 	 * The lircd gap calculation expects the write function to
342 	 * wait for the actual IR signal to be transmitted before
343 	 * returning.
344 	 */
345 	towait = ktime_us_delta(ktime_add_us(start, duration),
346 				ktime_get());
347 	if (towait > 0) {
348 		set_current_state(TASK_INTERRUPTIBLE);
349 		schedule_timeout(usecs_to_jiffies(towait));
350 	}
351 
352 	return n;
353 out_kfree:
354 	kfree(txbuf);
355 out_kfree_raw:
356 	kfree(raw);
357 out_unlock:
358 	mutex_unlock(&dev->lock);
359 	return ret;
360 }
361 
362 static long lirc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
363 {
364 	struct lirc_fh *fh = file->private_data;
365 	struct rc_dev *dev = fh->rc;
366 	u32 __user *argp = (u32 __user *)(arg);
367 	u32 val = 0;
368 	int ret;
369 
370 	if (_IOC_DIR(cmd) & _IOC_WRITE) {
371 		ret = get_user(val, argp);
372 		if (ret)
373 			return ret;
374 	}
375 
376 	ret = mutex_lock_interruptible(&dev->lock);
377 	if (ret)
378 		return ret;
379 
380 	if (!dev->registered) {
381 		ret = -ENODEV;
382 		goto out;
383 	}
384 
385 	switch (cmd) {
386 	case LIRC_GET_FEATURES:
387 		if (dev->driver_type == RC_DRIVER_SCANCODE)
388 			val |= LIRC_CAN_REC_SCANCODE;
389 
390 		if (dev->driver_type == RC_DRIVER_IR_RAW) {
391 			val |= LIRC_CAN_REC_MODE2;
392 			if (dev->rx_resolution)
393 				val |= LIRC_CAN_GET_REC_RESOLUTION;
394 		}
395 
396 		if (dev->tx_ir) {
397 			val |= LIRC_CAN_SEND_PULSE;
398 			if (dev->s_tx_mask)
399 				val |= LIRC_CAN_SET_TRANSMITTER_MASK;
400 			if (dev->s_tx_carrier)
401 				val |= LIRC_CAN_SET_SEND_CARRIER;
402 			if (dev->s_tx_duty_cycle)
403 				val |= LIRC_CAN_SET_SEND_DUTY_CYCLE;
404 		}
405 
406 		if (dev->s_rx_carrier_range)
407 			val |= LIRC_CAN_SET_REC_CARRIER |
408 				LIRC_CAN_SET_REC_CARRIER_RANGE;
409 
410 		if (dev->s_wideband_receiver)
411 			val |= LIRC_CAN_USE_WIDEBAND_RECEIVER;
412 
413 		if (dev->s_carrier_report)
414 			val |= LIRC_CAN_MEASURE_CARRIER;
415 
416 		if (dev->max_timeout)
417 			val |= LIRC_CAN_SET_REC_TIMEOUT;
418 
419 		break;
420 
421 	/* mode support */
422 	case LIRC_GET_REC_MODE:
423 		if (dev->driver_type == RC_DRIVER_IR_RAW_TX)
424 			ret = -ENOTTY;
425 		else
426 			val = fh->rec_mode;
427 		break;
428 
429 	case LIRC_SET_REC_MODE:
430 		switch (dev->driver_type) {
431 		case RC_DRIVER_IR_RAW_TX:
432 			ret = -ENOTTY;
433 			break;
434 		case RC_DRIVER_SCANCODE:
435 			if (val != LIRC_MODE_SCANCODE)
436 				ret = -EINVAL;
437 			break;
438 		case RC_DRIVER_IR_RAW:
439 			if (!(val == LIRC_MODE_MODE2 ||
440 			      val == LIRC_MODE_SCANCODE))
441 				ret = -EINVAL;
442 			break;
443 		}
444 
445 		if (!ret)
446 			fh->rec_mode = val;
447 		break;
448 
449 	case LIRC_GET_SEND_MODE:
450 		if (!dev->tx_ir)
451 			ret = -ENOTTY;
452 		else
453 			val = fh->send_mode;
454 		break;
455 
456 	case LIRC_SET_SEND_MODE:
457 		if (!dev->tx_ir)
458 			ret = -ENOTTY;
459 		else if (!(val == LIRC_MODE_PULSE || val == LIRC_MODE_SCANCODE))
460 			ret = -EINVAL;
461 		else
462 			fh->send_mode = val;
463 		break;
464 
465 	/* TX settings */
466 	case LIRC_SET_TRANSMITTER_MASK:
467 		if (!dev->s_tx_mask)
468 			ret = -ENOTTY;
469 		else
470 			ret = dev->s_tx_mask(dev, val);
471 		break;
472 
473 	case LIRC_SET_SEND_CARRIER:
474 		if (!dev->s_tx_carrier)
475 			ret = -ENOTTY;
476 		else
477 			ret = dev->s_tx_carrier(dev, val);
478 		break;
479 
480 	case LIRC_SET_SEND_DUTY_CYCLE:
481 		if (!dev->s_tx_duty_cycle)
482 			ret = -ENOTTY;
483 		else if (val <= 0 || val >= 100)
484 			ret = -EINVAL;
485 		else
486 			ret = dev->s_tx_duty_cycle(dev, val);
487 		break;
488 
489 	/* RX settings */
490 	case LIRC_SET_REC_CARRIER:
491 		if (!dev->s_rx_carrier_range)
492 			ret = -ENOTTY;
493 		else if (val <= 0)
494 			ret = -EINVAL;
495 		else
496 			ret = dev->s_rx_carrier_range(dev, fh->carrier_low,
497 						      val);
498 		break;
499 
500 	case LIRC_SET_REC_CARRIER_RANGE:
501 		if (!dev->s_rx_carrier_range)
502 			ret = -ENOTTY;
503 		else if (val <= 0)
504 			ret = -EINVAL;
505 		else
506 			fh->carrier_low = val;
507 		break;
508 
509 	case LIRC_GET_REC_RESOLUTION:
510 		if (!dev->rx_resolution)
511 			ret = -ENOTTY;
512 		else
513 			val = dev->rx_resolution;
514 		break;
515 
516 	case LIRC_SET_WIDEBAND_RECEIVER:
517 		if (!dev->s_wideband_receiver)
518 			ret = -ENOTTY;
519 		else
520 			ret = dev->s_wideband_receiver(dev, !!val);
521 		break;
522 
523 	case LIRC_SET_MEASURE_CARRIER_MODE:
524 		if (!dev->s_carrier_report)
525 			ret = -ENOTTY;
526 		else
527 			ret = dev->s_carrier_report(dev, !!val);
528 		break;
529 
530 	/* Generic timeout support */
531 	case LIRC_GET_MIN_TIMEOUT:
532 		if (!dev->max_timeout)
533 			ret = -ENOTTY;
534 		else
535 			val = dev->min_timeout;
536 		break;
537 
538 	case LIRC_GET_MAX_TIMEOUT:
539 		if (!dev->max_timeout)
540 			ret = -ENOTTY;
541 		else
542 			val = dev->max_timeout;
543 		break;
544 
545 	case LIRC_SET_REC_TIMEOUT:
546 		if (!dev->max_timeout) {
547 			ret = -ENOTTY;
548 		} else {
549 			if (val < dev->min_timeout || val > dev->max_timeout)
550 				ret = -EINVAL;
551 			else if (dev->s_timeout)
552 				ret = dev->s_timeout(dev, val);
553 			else
554 				dev->timeout = val;
555 		}
556 		break;
557 
558 	case LIRC_GET_REC_TIMEOUT:
559 		if (!dev->timeout)
560 			ret = -ENOTTY;
561 		else
562 			val = dev->timeout;
563 		break;
564 
565 	case LIRC_SET_REC_TIMEOUT_REPORTS:
566 		if (dev->driver_type != RC_DRIVER_IR_RAW)
567 			ret = -ENOTTY;
568 		break;
569 
570 	default:
571 		ret = -ENOTTY;
572 	}
573 
574 	if (!ret && _IOC_DIR(cmd) & _IOC_READ)
575 		ret = put_user(val, argp);
576 
577 out:
578 	mutex_unlock(&dev->lock);
579 	return ret;
580 }
581 
582 static __poll_t lirc_poll(struct file *file, struct poll_table_struct *wait)
583 {
584 	struct lirc_fh *fh = file->private_data;
585 	struct rc_dev *rcdev = fh->rc;
586 	__poll_t events = 0;
587 
588 	poll_wait(file, &fh->wait_poll, wait);
589 
590 	if (!rcdev->registered) {
591 		events = EPOLLHUP | EPOLLERR;
592 	} else if (rcdev->driver_type != RC_DRIVER_IR_RAW_TX) {
593 		if (fh->rec_mode == LIRC_MODE_SCANCODE &&
594 		    !kfifo_is_empty(&fh->scancodes))
595 			events = EPOLLIN | EPOLLRDNORM;
596 
597 		if (fh->rec_mode == LIRC_MODE_MODE2 &&
598 		    !kfifo_is_empty(&fh->rawir))
599 			events = EPOLLIN | EPOLLRDNORM;
600 	}
601 
602 	return events;
603 }
604 
605 static ssize_t lirc_read_mode2(struct file *file, char __user *buffer,
606 			       size_t length)
607 {
608 	struct lirc_fh *fh = file->private_data;
609 	struct rc_dev *rcdev = fh->rc;
610 	unsigned int copied;
611 	int ret;
612 
613 	if (length < sizeof(unsigned int) || length % sizeof(unsigned int))
614 		return -EINVAL;
615 
616 	do {
617 		if (kfifo_is_empty(&fh->rawir)) {
618 			if (file->f_flags & O_NONBLOCK)
619 				return -EAGAIN;
620 
621 			ret = wait_event_interruptible(fh->wait_poll,
622 					!kfifo_is_empty(&fh->rawir) ||
623 					!rcdev->registered);
624 			if (ret)
625 				return ret;
626 		}
627 
628 		if (!rcdev->registered)
629 			return -ENODEV;
630 
631 		ret = mutex_lock_interruptible(&rcdev->lock);
632 		if (ret)
633 			return ret;
634 		ret = kfifo_to_user(&fh->rawir, buffer, length, &copied);
635 		mutex_unlock(&rcdev->lock);
636 		if (ret)
637 			return ret;
638 	} while (copied == 0);
639 
640 	return copied;
641 }
642 
643 static ssize_t lirc_read_scancode(struct file *file, char __user *buffer,
644 				  size_t length)
645 {
646 	struct lirc_fh *fh = file->private_data;
647 	struct rc_dev *rcdev = fh->rc;
648 	unsigned int copied;
649 	int ret;
650 
651 	if (length < sizeof(struct lirc_scancode) ||
652 	    length % sizeof(struct lirc_scancode))
653 		return -EINVAL;
654 
655 	do {
656 		if (kfifo_is_empty(&fh->scancodes)) {
657 			if (file->f_flags & O_NONBLOCK)
658 				return -EAGAIN;
659 
660 			ret = wait_event_interruptible(fh->wait_poll,
661 					!kfifo_is_empty(&fh->scancodes) ||
662 					!rcdev->registered);
663 			if (ret)
664 				return ret;
665 		}
666 
667 		if (!rcdev->registered)
668 			return -ENODEV;
669 
670 		ret = mutex_lock_interruptible(&rcdev->lock);
671 		if (ret)
672 			return ret;
673 		ret = kfifo_to_user(&fh->scancodes, buffer, length, &copied);
674 		mutex_unlock(&rcdev->lock);
675 		if (ret)
676 			return ret;
677 	} while (copied == 0);
678 
679 	return copied;
680 }
681 
682 static ssize_t lirc_read(struct file *file, char __user *buffer, size_t length,
683 			 loff_t *ppos)
684 {
685 	struct lirc_fh *fh = file->private_data;
686 	struct rc_dev *rcdev = fh->rc;
687 
688 	if (rcdev->driver_type == RC_DRIVER_IR_RAW_TX)
689 		return -EINVAL;
690 
691 	if (!rcdev->registered)
692 		return -ENODEV;
693 
694 	if (fh->rec_mode == LIRC_MODE_MODE2)
695 		return lirc_read_mode2(file, buffer, length);
696 	else /* LIRC_MODE_SCANCODE */
697 		return lirc_read_scancode(file, buffer, length);
698 }
699 
700 static const struct file_operations lirc_fops = {
701 	.owner		= THIS_MODULE,
702 	.write		= lirc_transmit,
703 	.unlocked_ioctl	= lirc_ioctl,
704 	.compat_ioctl	= compat_ptr_ioctl,
705 	.read		= lirc_read,
706 	.poll		= lirc_poll,
707 	.open		= lirc_open,
708 	.release	= lirc_close,
709 	.llseek		= no_llseek,
710 };
711 
712 static void lirc_release_device(struct device *ld)
713 {
714 	struct rc_dev *rcdev = container_of(ld, struct rc_dev, lirc_dev);
715 
716 	put_device(&rcdev->dev);
717 }
718 
719 int lirc_register(struct rc_dev *dev)
720 {
721 	const char *rx_type, *tx_type;
722 	int err, minor;
723 
724 	minor = ida_alloc_max(&lirc_ida, RC_DEV_MAX - 1, GFP_KERNEL);
725 	if (minor < 0)
726 		return minor;
727 
728 	device_initialize(&dev->lirc_dev);
729 	dev->lirc_dev.class = &lirc_class;
730 	dev->lirc_dev.parent = &dev->dev;
731 	dev->lirc_dev.release = lirc_release_device;
732 	dev->lirc_dev.devt = MKDEV(MAJOR(lirc_base_dev), minor);
733 	dev_set_name(&dev->lirc_dev, "lirc%d", minor);
734 
735 	INIT_LIST_HEAD(&dev->lirc_fh);
736 	spin_lock_init(&dev->lirc_fh_lock);
737 
738 	cdev_init(&dev->lirc_cdev, &lirc_fops);
739 
740 	err = cdev_device_add(&dev->lirc_cdev, &dev->lirc_dev);
741 	if (err)
742 		goto out_ida;
743 
744 	get_device(&dev->dev);
745 
746 	switch (dev->driver_type) {
747 	case RC_DRIVER_SCANCODE:
748 		rx_type = "scancode";
749 		break;
750 	case RC_DRIVER_IR_RAW:
751 		rx_type = "raw IR";
752 		break;
753 	default:
754 		rx_type = "no";
755 		break;
756 	}
757 
758 	if (dev->tx_ir)
759 		tx_type = "raw IR";
760 	else
761 		tx_type = "no";
762 
763 	dev_info(&dev->dev, "lirc_dev: driver %s registered at minor = %d, %s receiver, %s transmitter",
764 		 dev->driver_name, minor, rx_type, tx_type);
765 
766 	return 0;
767 
768 out_ida:
769 	ida_free(&lirc_ida, minor);
770 	return err;
771 }
772 
773 void lirc_unregister(struct rc_dev *dev)
774 {
775 	unsigned long flags;
776 	struct lirc_fh *fh;
777 
778 	dev_dbg(&dev->dev, "lirc_dev: driver %s unregistered from minor = %d\n",
779 		dev->driver_name, MINOR(dev->lirc_dev.devt));
780 
781 	spin_lock_irqsave(&dev->lirc_fh_lock, flags);
782 	list_for_each_entry(fh, &dev->lirc_fh, list)
783 		wake_up_poll(&fh->wait_poll, EPOLLHUP | EPOLLERR);
784 	spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
785 
786 	cdev_device_del(&dev->lirc_cdev, &dev->lirc_dev);
787 	ida_free(&lirc_ida, MINOR(dev->lirc_dev.devt));
788 }
789 
790 int __init lirc_dev_init(void)
791 {
792 	int retval;
793 
794 	retval = class_register(&lirc_class);
795 	if (retval)
796 		return retval;
797 
798 	retval = alloc_chrdev_region(&lirc_base_dev, 0, RC_DEV_MAX, "lirc");
799 	if (retval) {
800 		class_unregister(&lirc_class);
801 		pr_err("alloc_chrdev_region failed\n");
802 		return retval;
803 	}
804 
805 	pr_debug("IR Remote Control driver registered, major %d\n",
806 		 MAJOR(lirc_base_dev));
807 
808 	return 0;
809 }
810 
811 void __exit lirc_dev_exit(void)
812 {
813 	class_unregister(&lirc_class);
814 	unregister_chrdev_region(lirc_base_dev, RC_DEV_MAX);
815 }
816 
817 struct rc_dev *rc_dev_get_from_fd(int fd, bool write)
818 {
819 	struct fd f = fdget(fd);
820 	struct lirc_fh *fh;
821 	struct rc_dev *dev;
822 
823 	if (!f.file)
824 		return ERR_PTR(-EBADF);
825 
826 	if (f.file->f_op != &lirc_fops) {
827 		fdput(f);
828 		return ERR_PTR(-EINVAL);
829 	}
830 
831 	if (write && !(f.file->f_mode & FMODE_WRITE))
832 		return ERR_PTR(-EPERM);
833 
834 	fh = f.file->private_data;
835 	dev = fh->rc;
836 
837 	get_device(&dev->dev);
838 	fdput(f);
839 
840 	return dev;
841 }
842 
843 MODULE_ALIAS("lirc_dev");
844