xref: /linux/sound/core/rawmidi.c (revision 662f11d55ffd02933e1bd275d732b97eddccf870)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Abstract layer for MIDI v1.0 stream
4  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5  */
6 
7 #include <sound/core.h>
8 #include <linux/major.h>
9 #include <linux/init.h>
10 #include <linux/sched/signal.h>
11 #include <linux/slab.h>
12 #include <linux/time.h>
13 #include <linux/wait.h>
14 #include <linux/mutex.h>
15 #include <linux/module.h>
16 #include <linux/delay.h>
17 #include <linux/mm.h>
18 #include <linux/nospec.h>
19 #include <sound/rawmidi.h>
20 #include <sound/info.h>
21 #include <sound/control.h>
22 #include <sound/minors.h>
23 #include <sound/initval.h>
24 
25 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
26 MODULE_DESCRIPTION("Midlevel RawMidi code for ALSA.");
27 MODULE_LICENSE("GPL");
28 
29 #ifdef CONFIG_SND_OSSEMUL
30 static int midi_map[SNDRV_CARDS];
31 static int amidi_map[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = 1};
32 module_param_array(midi_map, int, NULL, 0444);
33 MODULE_PARM_DESC(midi_map, "Raw MIDI device number assigned to 1st OSS device.");
34 module_param_array(amidi_map, int, NULL, 0444);
35 MODULE_PARM_DESC(amidi_map, "Raw MIDI device number assigned to 2nd OSS device.");
36 #endif /* CONFIG_SND_OSSEMUL */
37 
38 static int snd_rawmidi_free(struct snd_rawmidi *rmidi);
39 static int snd_rawmidi_dev_free(struct snd_device *device);
40 static int snd_rawmidi_dev_register(struct snd_device *device);
41 static int snd_rawmidi_dev_disconnect(struct snd_device *device);
42 
43 static LIST_HEAD(snd_rawmidi_devices);
44 static DEFINE_MUTEX(register_mutex);
45 
46 #define rmidi_err(rmidi, fmt, args...) \
47 	dev_err(&(rmidi)->dev, fmt, ##args)
48 #define rmidi_warn(rmidi, fmt, args...) \
49 	dev_warn(&(rmidi)->dev, fmt, ##args)
50 #define rmidi_dbg(rmidi, fmt, args...) \
51 	dev_dbg(&(rmidi)->dev, fmt, ##args)
52 
53 struct snd_rawmidi_status32 {
54 	s32 stream;
55 	s32 tstamp_sec;			/* Timestamp */
56 	s32 tstamp_nsec;
57 	u32 avail;			/* available bytes */
58 	u32 xruns;			/* count of overruns since last status (in bytes) */
59 	unsigned char reserved[16];	/* reserved for future use */
60 };
61 
62 #define SNDRV_RAWMIDI_IOCTL_STATUS32	_IOWR('W', 0x20, struct snd_rawmidi_status32)
63 
64 struct snd_rawmidi_status64 {
65 	int stream;
66 	u8 rsvd[4];			/* alignment */
67 	s64 tstamp_sec;			/* Timestamp */
68 	s64 tstamp_nsec;
69 	size_t avail;			/* available bytes */
70 	size_t xruns;			/* count of overruns since last status (in bytes) */
71 	unsigned char reserved[16];	/* reserved for future use */
72 };
73 
74 #define SNDRV_RAWMIDI_IOCTL_STATUS64	_IOWR('W', 0x20, struct snd_rawmidi_status64)
75 
76 static struct snd_rawmidi *snd_rawmidi_search(struct snd_card *card, int device)
77 {
78 	struct snd_rawmidi *rawmidi;
79 
80 	list_for_each_entry(rawmidi, &snd_rawmidi_devices, list)
81 		if (rawmidi->card == card && rawmidi->device == device)
82 			return rawmidi;
83 	return NULL;
84 }
85 
86 static inline unsigned short snd_rawmidi_file_flags(struct file *file)
87 {
88 	switch (file->f_mode & (FMODE_READ | FMODE_WRITE)) {
89 	case FMODE_WRITE:
90 		return SNDRV_RAWMIDI_LFLG_OUTPUT;
91 	case FMODE_READ:
92 		return SNDRV_RAWMIDI_LFLG_INPUT;
93 	default:
94 		return SNDRV_RAWMIDI_LFLG_OPEN;
95 	}
96 }
97 
98 static inline bool __snd_rawmidi_ready(struct snd_rawmidi_runtime *runtime)
99 {
100 	return runtime->avail >= runtime->avail_min;
101 }
102 
103 static bool snd_rawmidi_ready(struct snd_rawmidi_substream *substream)
104 {
105 	struct snd_rawmidi_runtime *runtime = substream->runtime;
106 	unsigned long flags;
107 	bool ready;
108 
109 	spin_lock_irqsave(&runtime->lock, flags);
110 	ready = __snd_rawmidi_ready(runtime);
111 	spin_unlock_irqrestore(&runtime->lock, flags);
112 	return ready;
113 }
114 
115 static inline int snd_rawmidi_ready_append(struct snd_rawmidi_substream *substream,
116 					   size_t count)
117 {
118 	struct snd_rawmidi_runtime *runtime = substream->runtime;
119 
120 	return runtime->avail >= runtime->avail_min &&
121 	       (!substream->append || runtime->avail >= count);
122 }
123 
124 static void snd_rawmidi_input_event_work(struct work_struct *work)
125 {
126 	struct snd_rawmidi_runtime *runtime =
127 		container_of(work, struct snd_rawmidi_runtime, event_work);
128 
129 	if (runtime->event)
130 		runtime->event(runtime->substream);
131 }
132 
133 /* buffer refcount management: call with runtime->lock held */
134 static inline void snd_rawmidi_buffer_ref(struct snd_rawmidi_runtime *runtime)
135 {
136 	runtime->buffer_ref++;
137 }
138 
139 static inline void snd_rawmidi_buffer_unref(struct snd_rawmidi_runtime *runtime)
140 {
141 	runtime->buffer_ref--;
142 }
143 
144 static int snd_rawmidi_runtime_create(struct snd_rawmidi_substream *substream)
145 {
146 	struct snd_rawmidi_runtime *runtime;
147 
148 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
149 	if (!runtime)
150 		return -ENOMEM;
151 	runtime->substream = substream;
152 	spin_lock_init(&runtime->lock);
153 	init_waitqueue_head(&runtime->sleep);
154 	INIT_WORK(&runtime->event_work, snd_rawmidi_input_event_work);
155 	runtime->event = NULL;
156 	runtime->buffer_size = PAGE_SIZE;
157 	runtime->avail_min = 1;
158 	if (substream->stream == SNDRV_RAWMIDI_STREAM_INPUT)
159 		runtime->avail = 0;
160 	else
161 		runtime->avail = runtime->buffer_size;
162 	runtime->buffer = kvzalloc(runtime->buffer_size, GFP_KERNEL);
163 	if (!runtime->buffer) {
164 		kfree(runtime);
165 		return -ENOMEM;
166 	}
167 	runtime->appl_ptr = runtime->hw_ptr = 0;
168 	substream->runtime = runtime;
169 	return 0;
170 }
171 
172 static int snd_rawmidi_runtime_free(struct snd_rawmidi_substream *substream)
173 {
174 	struct snd_rawmidi_runtime *runtime = substream->runtime;
175 
176 	kvfree(runtime->buffer);
177 	kfree(runtime);
178 	substream->runtime = NULL;
179 	return 0;
180 }
181 
182 static inline void snd_rawmidi_output_trigger(struct snd_rawmidi_substream *substream, int up)
183 {
184 	if (!substream->opened)
185 		return;
186 	substream->ops->trigger(substream, up);
187 }
188 
189 static void snd_rawmidi_input_trigger(struct snd_rawmidi_substream *substream, int up)
190 {
191 	if (!substream->opened)
192 		return;
193 	substream->ops->trigger(substream, up);
194 	if (!up)
195 		cancel_work_sync(&substream->runtime->event_work);
196 }
197 
198 static void __reset_runtime_ptrs(struct snd_rawmidi_runtime *runtime,
199 				 bool is_input)
200 {
201 	runtime->drain = 0;
202 	runtime->appl_ptr = runtime->hw_ptr = 0;
203 	runtime->avail = is_input ? 0 : runtime->buffer_size;
204 }
205 
206 static void reset_runtime_ptrs(struct snd_rawmidi_runtime *runtime,
207 			       bool is_input)
208 {
209 	unsigned long flags;
210 
211 	spin_lock_irqsave(&runtime->lock, flags);
212 	__reset_runtime_ptrs(runtime, is_input);
213 	spin_unlock_irqrestore(&runtime->lock, flags);
214 }
215 
216 int snd_rawmidi_drop_output(struct snd_rawmidi_substream *substream)
217 {
218 	snd_rawmidi_output_trigger(substream, 0);
219 	reset_runtime_ptrs(substream->runtime, false);
220 	return 0;
221 }
222 EXPORT_SYMBOL(snd_rawmidi_drop_output);
223 
224 int snd_rawmidi_drain_output(struct snd_rawmidi_substream *substream)
225 {
226 	int err;
227 	long timeout;
228 	struct snd_rawmidi_runtime *runtime = substream->runtime;
229 
230 	err = 0;
231 	runtime->drain = 1;
232 	timeout = wait_event_interruptible_timeout(runtime->sleep,
233 				(runtime->avail >= runtime->buffer_size),
234 				10*HZ);
235 	if (signal_pending(current))
236 		err = -ERESTARTSYS;
237 	if (runtime->avail < runtime->buffer_size && !timeout) {
238 		rmidi_warn(substream->rmidi,
239 			   "rawmidi drain error (avail = %li, buffer_size = %li)\n",
240 			   (long)runtime->avail, (long)runtime->buffer_size);
241 		err = -EIO;
242 	}
243 	runtime->drain = 0;
244 	if (err != -ERESTARTSYS) {
245 		/* we need wait a while to make sure that Tx FIFOs are empty */
246 		if (substream->ops->drain)
247 			substream->ops->drain(substream);
248 		else
249 			msleep(50);
250 		snd_rawmidi_drop_output(substream);
251 	}
252 	return err;
253 }
254 EXPORT_SYMBOL(snd_rawmidi_drain_output);
255 
256 int snd_rawmidi_drain_input(struct snd_rawmidi_substream *substream)
257 {
258 	snd_rawmidi_input_trigger(substream, 0);
259 	reset_runtime_ptrs(substream->runtime, true);
260 	return 0;
261 }
262 EXPORT_SYMBOL(snd_rawmidi_drain_input);
263 
264 /* look for an available substream for the given stream direction;
265  * if a specific subdevice is given, try to assign it
266  */
267 static int assign_substream(struct snd_rawmidi *rmidi, int subdevice,
268 			    int stream, int mode,
269 			    struct snd_rawmidi_substream **sub_ret)
270 {
271 	struct snd_rawmidi_substream *substream;
272 	struct snd_rawmidi_str *s = &rmidi->streams[stream];
273 	static const unsigned int info_flags[2] = {
274 		[SNDRV_RAWMIDI_STREAM_OUTPUT] = SNDRV_RAWMIDI_INFO_OUTPUT,
275 		[SNDRV_RAWMIDI_STREAM_INPUT] = SNDRV_RAWMIDI_INFO_INPUT,
276 	};
277 
278 	if (!(rmidi->info_flags & info_flags[stream]))
279 		return -ENXIO;
280 	if (subdevice >= 0 && subdevice >= s->substream_count)
281 		return -ENODEV;
282 
283 	list_for_each_entry(substream, &s->substreams, list) {
284 		if (substream->opened) {
285 			if (stream == SNDRV_RAWMIDI_STREAM_INPUT ||
286 			    !(mode & SNDRV_RAWMIDI_LFLG_APPEND) ||
287 			    !substream->append)
288 				continue;
289 		}
290 		if (subdevice < 0 || subdevice == substream->number) {
291 			*sub_ret = substream;
292 			return 0;
293 		}
294 	}
295 	return -EAGAIN;
296 }
297 
298 /* open and do ref-counting for the given substream */
299 static int open_substream(struct snd_rawmidi *rmidi,
300 			  struct snd_rawmidi_substream *substream,
301 			  int mode)
302 {
303 	int err;
304 
305 	if (substream->use_count == 0) {
306 		err = snd_rawmidi_runtime_create(substream);
307 		if (err < 0)
308 			return err;
309 		err = substream->ops->open(substream);
310 		if (err < 0) {
311 			snd_rawmidi_runtime_free(substream);
312 			return err;
313 		}
314 		substream->opened = 1;
315 		substream->active_sensing = 0;
316 		if (mode & SNDRV_RAWMIDI_LFLG_APPEND)
317 			substream->append = 1;
318 		substream->pid = get_pid(task_pid(current));
319 		rmidi->streams[substream->stream].substream_opened++;
320 	}
321 	substream->use_count++;
322 	return 0;
323 }
324 
325 static void close_substream(struct snd_rawmidi *rmidi,
326 			    struct snd_rawmidi_substream *substream,
327 			    int cleanup);
328 
329 static int rawmidi_open_priv(struct snd_rawmidi *rmidi, int subdevice, int mode,
330 			     struct snd_rawmidi_file *rfile)
331 {
332 	struct snd_rawmidi_substream *sinput = NULL, *soutput = NULL;
333 	int err;
334 
335 	rfile->input = rfile->output = NULL;
336 	if (mode & SNDRV_RAWMIDI_LFLG_INPUT) {
337 		err = assign_substream(rmidi, subdevice,
338 				       SNDRV_RAWMIDI_STREAM_INPUT,
339 				       mode, &sinput);
340 		if (err < 0)
341 			return err;
342 	}
343 	if (mode & SNDRV_RAWMIDI_LFLG_OUTPUT) {
344 		err = assign_substream(rmidi, subdevice,
345 				       SNDRV_RAWMIDI_STREAM_OUTPUT,
346 				       mode, &soutput);
347 		if (err < 0)
348 			return err;
349 	}
350 
351 	if (sinput) {
352 		err = open_substream(rmidi, sinput, mode);
353 		if (err < 0)
354 			return err;
355 	}
356 	if (soutput) {
357 		err = open_substream(rmidi, soutput, mode);
358 		if (err < 0) {
359 			if (sinput)
360 				close_substream(rmidi, sinput, 0);
361 			return err;
362 		}
363 	}
364 
365 	rfile->rmidi = rmidi;
366 	rfile->input = sinput;
367 	rfile->output = soutput;
368 	return 0;
369 }
370 
371 /* called from sound/core/seq/seq_midi.c */
372 int snd_rawmidi_kernel_open(struct snd_card *card, int device, int subdevice,
373 			    int mode, struct snd_rawmidi_file *rfile)
374 {
375 	struct snd_rawmidi *rmidi;
376 	int err = 0;
377 
378 	if (snd_BUG_ON(!rfile))
379 		return -EINVAL;
380 
381 	mutex_lock(&register_mutex);
382 	rmidi = snd_rawmidi_search(card, device);
383 	if (!rmidi)
384 		err = -ENODEV;
385 	else if (!try_module_get(rmidi->card->module))
386 		err = -ENXIO;
387 	mutex_unlock(&register_mutex);
388 	if (err < 0)
389 		return err;
390 
391 	mutex_lock(&rmidi->open_mutex);
392 	err = rawmidi_open_priv(rmidi, subdevice, mode, rfile);
393 	mutex_unlock(&rmidi->open_mutex);
394 	if (err < 0)
395 		module_put(rmidi->card->module);
396 	return err;
397 }
398 EXPORT_SYMBOL(snd_rawmidi_kernel_open);
399 
400 static int snd_rawmidi_open(struct inode *inode, struct file *file)
401 {
402 	int maj = imajor(inode);
403 	struct snd_card *card;
404 	int subdevice;
405 	unsigned short fflags;
406 	int err;
407 	struct snd_rawmidi *rmidi;
408 	struct snd_rawmidi_file *rawmidi_file = NULL;
409 	wait_queue_entry_t wait;
410 
411 	if ((file->f_flags & O_APPEND) && !(file->f_flags & O_NONBLOCK))
412 		return -EINVAL;		/* invalid combination */
413 
414 	err = stream_open(inode, file);
415 	if (err < 0)
416 		return err;
417 
418 	if (maj == snd_major) {
419 		rmidi = snd_lookup_minor_data(iminor(inode),
420 					      SNDRV_DEVICE_TYPE_RAWMIDI);
421 #ifdef CONFIG_SND_OSSEMUL
422 	} else if (maj == SOUND_MAJOR) {
423 		rmidi = snd_lookup_oss_minor_data(iminor(inode),
424 						  SNDRV_OSS_DEVICE_TYPE_MIDI);
425 #endif
426 	} else
427 		return -ENXIO;
428 
429 	if (rmidi == NULL)
430 		return -ENODEV;
431 
432 	if (!try_module_get(rmidi->card->module)) {
433 		snd_card_unref(rmidi->card);
434 		return -ENXIO;
435 	}
436 
437 	mutex_lock(&rmidi->open_mutex);
438 	card = rmidi->card;
439 	err = snd_card_file_add(card, file);
440 	if (err < 0)
441 		goto __error_card;
442 	fflags = snd_rawmidi_file_flags(file);
443 	if ((file->f_flags & O_APPEND) || maj == SOUND_MAJOR) /* OSS emul? */
444 		fflags |= SNDRV_RAWMIDI_LFLG_APPEND;
445 	rawmidi_file = kmalloc(sizeof(*rawmidi_file), GFP_KERNEL);
446 	if (rawmidi_file == NULL) {
447 		err = -ENOMEM;
448 		goto __error;
449 	}
450 	init_waitqueue_entry(&wait, current);
451 	add_wait_queue(&rmidi->open_wait, &wait);
452 	while (1) {
453 		subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_RAWMIDI);
454 		err = rawmidi_open_priv(rmidi, subdevice, fflags, rawmidi_file);
455 		if (err >= 0)
456 			break;
457 		if (err == -EAGAIN) {
458 			if (file->f_flags & O_NONBLOCK) {
459 				err = -EBUSY;
460 				break;
461 			}
462 		} else
463 			break;
464 		set_current_state(TASK_INTERRUPTIBLE);
465 		mutex_unlock(&rmidi->open_mutex);
466 		schedule();
467 		mutex_lock(&rmidi->open_mutex);
468 		if (rmidi->card->shutdown) {
469 			err = -ENODEV;
470 			break;
471 		}
472 		if (signal_pending(current)) {
473 			err = -ERESTARTSYS;
474 			break;
475 		}
476 	}
477 	remove_wait_queue(&rmidi->open_wait, &wait);
478 	if (err < 0) {
479 		kfree(rawmidi_file);
480 		goto __error;
481 	}
482 #ifdef CONFIG_SND_OSSEMUL
483 	if (rawmidi_file->input && rawmidi_file->input->runtime)
484 		rawmidi_file->input->runtime->oss = (maj == SOUND_MAJOR);
485 	if (rawmidi_file->output && rawmidi_file->output->runtime)
486 		rawmidi_file->output->runtime->oss = (maj == SOUND_MAJOR);
487 #endif
488 	file->private_data = rawmidi_file;
489 	mutex_unlock(&rmidi->open_mutex);
490 	snd_card_unref(rmidi->card);
491 	return 0;
492 
493  __error:
494 	snd_card_file_remove(card, file);
495  __error_card:
496 	mutex_unlock(&rmidi->open_mutex);
497 	module_put(rmidi->card->module);
498 	snd_card_unref(rmidi->card);
499 	return err;
500 }
501 
502 static void close_substream(struct snd_rawmidi *rmidi,
503 			    struct snd_rawmidi_substream *substream,
504 			    int cleanup)
505 {
506 	if (--substream->use_count)
507 		return;
508 
509 	if (cleanup) {
510 		if (substream->stream == SNDRV_RAWMIDI_STREAM_INPUT)
511 			snd_rawmidi_input_trigger(substream, 0);
512 		else {
513 			if (substream->active_sensing) {
514 				unsigned char buf = 0xfe;
515 				/* sending single active sensing message
516 				 * to shut the device up
517 				 */
518 				snd_rawmidi_kernel_write(substream, &buf, 1);
519 			}
520 			if (snd_rawmidi_drain_output(substream) == -ERESTARTSYS)
521 				snd_rawmidi_output_trigger(substream, 0);
522 		}
523 	}
524 	substream->ops->close(substream);
525 	if (substream->runtime->private_free)
526 		substream->runtime->private_free(substream);
527 	snd_rawmidi_runtime_free(substream);
528 	substream->opened = 0;
529 	substream->append = 0;
530 	put_pid(substream->pid);
531 	substream->pid = NULL;
532 	rmidi->streams[substream->stream].substream_opened--;
533 }
534 
535 static void rawmidi_release_priv(struct snd_rawmidi_file *rfile)
536 {
537 	struct snd_rawmidi *rmidi;
538 
539 	rmidi = rfile->rmidi;
540 	mutex_lock(&rmidi->open_mutex);
541 	if (rfile->input) {
542 		close_substream(rmidi, rfile->input, 1);
543 		rfile->input = NULL;
544 	}
545 	if (rfile->output) {
546 		close_substream(rmidi, rfile->output, 1);
547 		rfile->output = NULL;
548 	}
549 	rfile->rmidi = NULL;
550 	mutex_unlock(&rmidi->open_mutex);
551 	wake_up(&rmidi->open_wait);
552 }
553 
554 /* called from sound/core/seq/seq_midi.c */
555 int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile)
556 {
557 	struct snd_rawmidi *rmidi;
558 
559 	if (snd_BUG_ON(!rfile))
560 		return -ENXIO;
561 
562 	rmidi = rfile->rmidi;
563 	rawmidi_release_priv(rfile);
564 	module_put(rmidi->card->module);
565 	return 0;
566 }
567 EXPORT_SYMBOL(snd_rawmidi_kernel_release);
568 
569 static int snd_rawmidi_release(struct inode *inode, struct file *file)
570 {
571 	struct snd_rawmidi_file *rfile;
572 	struct snd_rawmidi *rmidi;
573 	struct module *module;
574 
575 	rfile = file->private_data;
576 	rmidi = rfile->rmidi;
577 	rawmidi_release_priv(rfile);
578 	kfree(rfile);
579 	module = rmidi->card->module;
580 	snd_card_file_remove(rmidi->card, file);
581 	module_put(module);
582 	return 0;
583 }
584 
585 static int snd_rawmidi_info(struct snd_rawmidi_substream *substream,
586 			    struct snd_rawmidi_info *info)
587 {
588 	struct snd_rawmidi *rmidi;
589 
590 	if (substream == NULL)
591 		return -ENODEV;
592 	rmidi = substream->rmidi;
593 	memset(info, 0, sizeof(*info));
594 	info->card = rmidi->card->number;
595 	info->device = rmidi->device;
596 	info->subdevice = substream->number;
597 	info->stream = substream->stream;
598 	info->flags = rmidi->info_flags;
599 	strcpy(info->id, rmidi->id);
600 	strcpy(info->name, rmidi->name);
601 	strcpy(info->subname, substream->name);
602 	info->subdevices_count = substream->pstr->substream_count;
603 	info->subdevices_avail = (substream->pstr->substream_count -
604 				  substream->pstr->substream_opened);
605 	return 0;
606 }
607 
608 static int snd_rawmidi_info_user(struct snd_rawmidi_substream *substream,
609 				 struct snd_rawmidi_info __user *_info)
610 {
611 	struct snd_rawmidi_info info;
612 	int err;
613 
614 	err = snd_rawmidi_info(substream, &info);
615 	if (err < 0)
616 		return err;
617 	if (copy_to_user(_info, &info, sizeof(struct snd_rawmidi_info)))
618 		return -EFAULT;
619 	return 0;
620 }
621 
622 static int __snd_rawmidi_info_select(struct snd_card *card,
623 				     struct snd_rawmidi_info *info)
624 {
625 	struct snd_rawmidi *rmidi;
626 	struct snd_rawmidi_str *pstr;
627 	struct snd_rawmidi_substream *substream;
628 
629 	rmidi = snd_rawmidi_search(card, info->device);
630 	if (!rmidi)
631 		return -ENXIO;
632 	if (info->stream < 0 || info->stream > 1)
633 		return -EINVAL;
634 	info->stream = array_index_nospec(info->stream, 2);
635 	pstr = &rmidi->streams[info->stream];
636 	if (pstr->substream_count == 0)
637 		return -ENOENT;
638 	if (info->subdevice >= pstr->substream_count)
639 		return -ENXIO;
640 	list_for_each_entry(substream, &pstr->substreams, list) {
641 		if ((unsigned int)substream->number == info->subdevice)
642 			return snd_rawmidi_info(substream, info);
643 	}
644 	return -ENXIO;
645 }
646 
647 int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info)
648 {
649 	int ret;
650 
651 	mutex_lock(&register_mutex);
652 	ret = __snd_rawmidi_info_select(card, info);
653 	mutex_unlock(&register_mutex);
654 	return ret;
655 }
656 EXPORT_SYMBOL(snd_rawmidi_info_select);
657 
658 static int snd_rawmidi_info_select_user(struct snd_card *card,
659 					struct snd_rawmidi_info __user *_info)
660 {
661 	int err;
662 	struct snd_rawmidi_info info;
663 
664 	if (get_user(info.device, &_info->device))
665 		return -EFAULT;
666 	if (get_user(info.stream, &_info->stream))
667 		return -EFAULT;
668 	if (get_user(info.subdevice, &_info->subdevice))
669 		return -EFAULT;
670 	err = snd_rawmidi_info_select(card, &info);
671 	if (err < 0)
672 		return err;
673 	if (copy_to_user(_info, &info, sizeof(struct snd_rawmidi_info)))
674 		return -EFAULT;
675 	return 0;
676 }
677 
678 static int resize_runtime_buffer(struct snd_rawmidi_runtime *runtime,
679 				 struct snd_rawmidi_params *params,
680 				 bool is_input)
681 {
682 	char *newbuf, *oldbuf;
683 	unsigned int framing = params->mode & SNDRV_RAWMIDI_MODE_FRAMING_MASK;
684 
685 	if (params->buffer_size < 32 || params->buffer_size > 1024L * 1024L)
686 		return -EINVAL;
687 	if (framing == SNDRV_RAWMIDI_MODE_FRAMING_TSTAMP && (params->buffer_size & 0x1f) != 0)
688 		return -EINVAL;
689 	if (params->avail_min < 1 || params->avail_min > params->buffer_size)
690 		return -EINVAL;
691 	if (params->buffer_size != runtime->buffer_size) {
692 		newbuf = kvzalloc(params->buffer_size, GFP_KERNEL);
693 		if (!newbuf)
694 			return -ENOMEM;
695 		spin_lock_irq(&runtime->lock);
696 		if (runtime->buffer_ref) {
697 			spin_unlock_irq(&runtime->lock);
698 			kvfree(newbuf);
699 			return -EBUSY;
700 		}
701 		oldbuf = runtime->buffer;
702 		runtime->buffer = newbuf;
703 		runtime->buffer_size = params->buffer_size;
704 		__reset_runtime_ptrs(runtime, is_input);
705 		spin_unlock_irq(&runtime->lock);
706 		kvfree(oldbuf);
707 	}
708 	runtime->avail_min = params->avail_min;
709 	return 0;
710 }
711 
712 int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
713 			      struct snd_rawmidi_params *params)
714 {
715 	if (substream->append && substream->use_count > 1)
716 		return -EBUSY;
717 	snd_rawmidi_drain_output(substream);
718 	substream->active_sensing = !params->no_active_sensing;
719 	return resize_runtime_buffer(substream->runtime, params, false);
720 }
721 EXPORT_SYMBOL(snd_rawmidi_output_params);
722 
723 int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
724 			     struct snd_rawmidi_params *params)
725 {
726 	unsigned int framing = params->mode & SNDRV_RAWMIDI_MODE_FRAMING_MASK;
727 	unsigned int clock_type = params->mode & SNDRV_RAWMIDI_MODE_CLOCK_MASK;
728 	int err;
729 
730 	if (framing == SNDRV_RAWMIDI_MODE_FRAMING_NONE && clock_type != SNDRV_RAWMIDI_MODE_CLOCK_NONE)
731 		return -EINVAL;
732 	else if (clock_type > SNDRV_RAWMIDI_MODE_CLOCK_MONOTONIC_RAW)
733 		return -EINVAL;
734 	if (framing > SNDRV_RAWMIDI_MODE_FRAMING_TSTAMP)
735 		return -EINVAL;
736 	snd_rawmidi_drain_input(substream);
737 	err = resize_runtime_buffer(substream->runtime, params, true);
738 	if (err < 0)
739 		return err;
740 
741 	substream->framing = framing;
742 	substream->clock_type = clock_type;
743 	return 0;
744 }
745 EXPORT_SYMBOL(snd_rawmidi_input_params);
746 
747 static int snd_rawmidi_output_status(struct snd_rawmidi_substream *substream,
748 				     struct snd_rawmidi_status64 *status)
749 {
750 	struct snd_rawmidi_runtime *runtime = substream->runtime;
751 
752 	memset(status, 0, sizeof(*status));
753 	status->stream = SNDRV_RAWMIDI_STREAM_OUTPUT;
754 	spin_lock_irq(&runtime->lock);
755 	status->avail = runtime->avail;
756 	spin_unlock_irq(&runtime->lock);
757 	return 0;
758 }
759 
760 static int snd_rawmidi_input_status(struct snd_rawmidi_substream *substream,
761 				    struct snd_rawmidi_status64 *status)
762 {
763 	struct snd_rawmidi_runtime *runtime = substream->runtime;
764 
765 	memset(status, 0, sizeof(*status));
766 	status->stream = SNDRV_RAWMIDI_STREAM_INPUT;
767 	spin_lock_irq(&runtime->lock);
768 	status->avail = runtime->avail;
769 	status->xruns = runtime->xruns;
770 	runtime->xruns = 0;
771 	spin_unlock_irq(&runtime->lock);
772 	return 0;
773 }
774 
775 static int snd_rawmidi_ioctl_status32(struct snd_rawmidi_file *rfile,
776 				      struct snd_rawmidi_status32 __user *argp)
777 {
778 	int err = 0;
779 	struct snd_rawmidi_status32 __user *status = argp;
780 	struct snd_rawmidi_status32 status32;
781 	struct snd_rawmidi_status64 status64;
782 
783 	if (copy_from_user(&status32, argp,
784 			   sizeof(struct snd_rawmidi_status32)))
785 		return -EFAULT;
786 
787 	switch (status32.stream) {
788 	case SNDRV_RAWMIDI_STREAM_OUTPUT:
789 		if (rfile->output == NULL)
790 			return -EINVAL;
791 		err = snd_rawmidi_output_status(rfile->output, &status64);
792 		break;
793 	case SNDRV_RAWMIDI_STREAM_INPUT:
794 		if (rfile->input == NULL)
795 			return -EINVAL;
796 		err = snd_rawmidi_input_status(rfile->input, &status64);
797 		break;
798 	default:
799 		return -EINVAL;
800 	}
801 	if (err < 0)
802 		return err;
803 
804 	status32 = (struct snd_rawmidi_status32) {
805 		.stream = status64.stream,
806 		.tstamp_sec = status64.tstamp_sec,
807 		.tstamp_nsec = status64.tstamp_nsec,
808 		.avail = status64.avail,
809 		.xruns = status64.xruns,
810 	};
811 
812 	if (copy_to_user(status, &status32, sizeof(*status)))
813 		return -EFAULT;
814 
815 	return 0;
816 }
817 
818 static int snd_rawmidi_ioctl_status64(struct snd_rawmidi_file *rfile,
819 				      struct snd_rawmidi_status64 __user *argp)
820 {
821 	int err = 0;
822 	struct snd_rawmidi_status64 status;
823 
824 	if (copy_from_user(&status, argp, sizeof(struct snd_rawmidi_status64)))
825 		return -EFAULT;
826 
827 	switch (status.stream) {
828 	case SNDRV_RAWMIDI_STREAM_OUTPUT:
829 		if (rfile->output == NULL)
830 			return -EINVAL;
831 		err = snd_rawmidi_output_status(rfile->output, &status);
832 		break;
833 	case SNDRV_RAWMIDI_STREAM_INPUT:
834 		if (rfile->input == NULL)
835 			return -EINVAL;
836 		err = snd_rawmidi_input_status(rfile->input, &status);
837 		break;
838 	default:
839 		return -EINVAL;
840 	}
841 	if (err < 0)
842 		return err;
843 	if (copy_to_user(argp, &status,
844 			 sizeof(struct snd_rawmidi_status64)))
845 		return -EFAULT;
846 	return 0;
847 }
848 
849 static long snd_rawmidi_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
850 {
851 	struct snd_rawmidi_file *rfile;
852 	void __user *argp = (void __user *)arg;
853 
854 	rfile = file->private_data;
855 	if (((cmd >> 8) & 0xff) != 'W')
856 		return -ENOTTY;
857 	switch (cmd) {
858 	case SNDRV_RAWMIDI_IOCTL_PVERSION:
859 		return put_user(SNDRV_RAWMIDI_VERSION, (int __user *)argp) ? -EFAULT : 0;
860 	case SNDRV_RAWMIDI_IOCTL_INFO:
861 	{
862 		int stream;
863 		struct snd_rawmidi_info __user *info = argp;
864 
865 		if (get_user(stream, &info->stream))
866 			return -EFAULT;
867 		switch (stream) {
868 		case SNDRV_RAWMIDI_STREAM_INPUT:
869 			return snd_rawmidi_info_user(rfile->input, info);
870 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
871 			return snd_rawmidi_info_user(rfile->output, info);
872 		default:
873 			return -EINVAL;
874 		}
875 	}
876 	case SNDRV_RAWMIDI_IOCTL_USER_PVERSION:
877 		if (get_user(rfile->user_pversion, (unsigned int __user *)arg))
878 			return -EFAULT;
879 		return 0;
880 
881 	case SNDRV_RAWMIDI_IOCTL_PARAMS:
882 	{
883 		struct snd_rawmidi_params params;
884 
885 		if (copy_from_user(&params, argp, sizeof(struct snd_rawmidi_params)))
886 			return -EFAULT;
887 		if (rfile->user_pversion < SNDRV_PROTOCOL_VERSION(2, 0, 2)) {
888 			params.mode = 0;
889 			memset(params.reserved, 0, sizeof(params.reserved));
890 		}
891 		switch (params.stream) {
892 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
893 			if (rfile->output == NULL)
894 				return -EINVAL;
895 			return snd_rawmidi_output_params(rfile->output, &params);
896 		case SNDRV_RAWMIDI_STREAM_INPUT:
897 			if (rfile->input == NULL)
898 				return -EINVAL;
899 			return snd_rawmidi_input_params(rfile->input, &params);
900 		default:
901 			return -EINVAL;
902 		}
903 	}
904 	case SNDRV_RAWMIDI_IOCTL_STATUS32:
905 		return snd_rawmidi_ioctl_status32(rfile, argp);
906 	case SNDRV_RAWMIDI_IOCTL_STATUS64:
907 		return snd_rawmidi_ioctl_status64(rfile, argp);
908 	case SNDRV_RAWMIDI_IOCTL_DROP:
909 	{
910 		int val;
911 
912 		if (get_user(val, (int __user *) argp))
913 			return -EFAULT;
914 		switch (val) {
915 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
916 			if (rfile->output == NULL)
917 				return -EINVAL;
918 			return snd_rawmidi_drop_output(rfile->output);
919 		default:
920 			return -EINVAL;
921 		}
922 	}
923 	case SNDRV_RAWMIDI_IOCTL_DRAIN:
924 	{
925 		int val;
926 
927 		if (get_user(val, (int __user *) argp))
928 			return -EFAULT;
929 		switch (val) {
930 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
931 			if (rfile->output == NULL)
932 				return -EINVAL;
933 			return snd_rawmidi_drain_output(rfile->output);
934 		case SNDRV_RAWMIDI_STREAM_INPUT:
935 			if (rfile->input == NULL)
936 				return -EINVAL;
937 			return snd_rawmidi_drain_input(rfile->input);
938 		default:
939 			return -EINVAL;
940 		}
941 	}
942 	default:
943 		rmidi_dbg(rfile->rmidi,
944 			  "rawmidi: unknown command = 0x%x\n", cmd);
945 	}
946 	return -ENOTTY;
947 }
948 
949 static int snd_rawmidi_control_ioctl(struct snd_card *card,
950 				     struct snd_ctl_file *control,
951 				     unsigned int cmd,
952 				     unsigned long arg)
953 {
954 	void __user *argp = (void __user *)arg;
955 
956 	switch (cmd) {
957 	case SNDRV_CTL_IOCTL_RAWMIDI_NEXT_DEVICE:
958 	{
959 		int device;
960 
961 		if (get_user(device, (int __user *)argp))
962 			return -EFAULT;
963 		if (device >= SNDRV_RAWMIDI_DEVICES) /* next device is -1 */
964 			device = SNDRV_RAWMIDI_DEVICES - 1;
965 		mutex_lock(&register_mutex);
966 		device = device < 0 ? 0 : device + 1;
967 		while (device < SNDRV_RAWMIDI_DEVICES) {
968 			if (snd_rawmidi_search(card, device))
969 				break;
970 			device++;
971 		}
972 		if (device == SNDRV_RAWMIDI_DEVICES)
973 			device = -1;
974 		mutex_unlock(&register_mutex);
975 		if (put_user(device, (int __user *)argp))
976 			return -EFAULT;
977 		return 0;
978 	}
979 	case SNDRV_CTL_IOCTL_RAWMIDI_PREFER_SUBDEVICE:
980 	{
981 		int val;
982 
983 		if (get_user(val, (int __user *)argp))
984 			return -EFAULT;
985 		control->preferred_subdevice[SND_CTL_SUBDEV_RAWMIDI] = val;
986 		return 0;
987 	}
988 	case SNDRV_CTL_IOCTL_RAWMIDI_INFO:
989 		return snd_rawmidi_info_select_user(card, argp);
990 	}
991 	return -ENOIOCTLCMD;
992 }
993 
994 static int receive_with_tstamp_framing(struct snd_rawmidi_substream *substream,
995 			const unsigned char *buffer, int src_count, const struct timespec64 *tstamp)
996 {
997 	struct snd_rawmidi_runtime *runtime = substream->runtime;
998 	struct snd_rawmidi_framing_tstamp *dest_ptr;
999 	struct snd_rawmidi_framing_tstamp frame = { .tv_sec = tstamp->tv_sec, .tv_nsec = tstamp->tv_nsec };
1000 	int dest_frames = 0;
1001 	int orig_count = src_count;
1002 	int frame_size = sizeof(struct snd_rawmidi_framing_tstamp);
1003 
1004 	BUILD_BUG_ON(frame_size != 0x20);
1005 	if (snd_BUG_ON((runtime->hw_ptr & 0x1f) != 0))
1006 		return -EINVAL;
1007 
1008 	while (src_count > 0) {
1009 		if ((int)(runtime->buffer_size - runtime->avail) < frame_size) {
1010 			runtime->xruns += src_count;
1011 			break;
1012 		}
1013 		if (src_count >= SNDRV_RAWMIDI_FRAMING_DATA_LENGTH)
1014 			frame.length = SNDRV_RAWMIDI_FRAMING_DATA_LENGTH;
1015 		else {
1016 			frame.length = src_count;
1017 			memset(frame.data, 0, SNDRV_RAWMIDI_FRAMING_DATA_LENGTH);
1018 		}
1019 		memcpy(frame.data, buffer, frame.length);
1020 		buffer += frame.length;
1021 		src_count -= frame.length;
1022 		dest_ptr = (struct snd_rawmidi_framing_tstamp *) (runtime->buffer + runtime->hw_ptr);
1023 		*dest_ptr = frame;
1024 		runtime->avail += frame_size;
1025 		runtime->hw_ptr += frame_size;
1026 		runtime->hw_ptr %= runtime->buffer_size;
1027 		dest_frames++;
1028 	}
1029 	return orig_count - src_count;
1030 }
1031 
1032 static struct timespec64 get_framing_tstamp(struct snd_rawmidi_substream *substream)
1033 {
1034 	struct timespec64 ts64 = {0, 0};
1035 
1036 	switch (substream->clock_type) {
1037 	case SNDRV_RAWMIDI_MODE_CLOCK_MONOTONIC_RAW:
1038 		ktime_get_raw_ts64(&ts64);
1039 		break;
1040 	case SNDRV_RAWMIDI_MODE_CLOCK_MONOTONIC:
1041 		ktime_get_ts64(&ts64);
1042 		break;
1043 	case SNDRV_RAWMIDI_MODE_CLOCK_REALTIME:
1044 		ktime_get_real_ts64(&ts64);
1045 		break;
1046 	}
1047 	return ts64;
1048 }
1049 
1050 /**
1051  * snd_rawmidi_receive - receive the input data from the device
1052  * @substream: the rawmidi substream
1053  * @buffer: the buffer pointer
1054  * @count: the data size to read
1055  *
1056  * Reads the data from the internal buffer.
1057  *
1058  * Return: The size of read data, or a negative error code on failure.
1059  */
1060 int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
1061 			const unsigned char *buffer, int count)
1062 {
1063 	unsigned long flags;
1064 	struct timespec64 ts64 = get_framing_tstamp(substream);
1065 	int result = 0, count1;
1066 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1067 
1068 	if (!substream->opened)
1069 		return -EBADFD;
1070 	if (runtime->buffer == NULL) {
1071 		rmidi_dbg(substream->rmidi,
1072 			  "snd_rawmidi_receive: input is not active!!!\n");
1073 		return -EINVAL;
1074 	}
1075 
1076 	spin_lock_irqsave(&runtime->lock, flags);
1077 	if (substream->framing == SNDRV_RAWMIDI_MODE_FRAMING_TSTAMP) {
1078 		result = receive_with_tstamp_framing(substream, buffer, count, &ts64);
1079 	} else if (count == 1) {	/* special case, faster code */
1080 		substream->bytes++;
1081 		if (runtime->avail < runtime->buffer_size) {
1082 			runtime->buffer[runtime->hw_ptr++] = buffer[0];
1083 			runtime->hw_ptr %= runtime->buffer_size;
1084 			runtime->avail++;
1085 			result++;
1086 		} else {
1087 			runtime->xruns++;
1088 		}
1089 	} else {
1090 		substream->bytes += count;
1091 		count1 = runtime->buffer_size - runtime->hw_ptr;
1092 		if (count1 > count)
1093 			count1 = count;
1094 		if (count1 > (int)(runtime->buffer_size - runtime->avail))
1095 			count1 = runtime->buffer_size - runtime->avail;
1096 		memcpy(runtime->buffer + runtime->hw_ptr, buffer, count1);
1097 		runtime->hw_ptr += count1;
1098 		runtime->hw_ptr %= runtime->buffer_size;
1099 		runtime->avail += count1;
1100 		count -= count1;
1101 		result += count1;
1102 		if (count > 0) {
1103 			buffer += count1;
1104 			count1 = count;
1105 			if (count1 > (int)(runtime->buffer_size - runtime->avail)) {
1106 				count1 = runtime->buffer_size - runtime->avail;
1107 				runtime->xruns += count - count1;
1108 			}
1109 			if (count1 > 0) {
1110 				memcpy(runtime->buffer, buffer, count1);
1111 				runtime->hw_ptr = count1;
1112 				runtime->avail += count1;
1113 				result += count1;
1114 			}
1115 		}
1116 	}
1117 	if (result > 0) {
1118 		if (runtime->event)
1119 			schedule_work(&runtime->event_work);
1120 		else if (__snd_rawmidi_ready(runtime))
1121 			wake_up(&runtime->sleep);
1122 	}
1123 	spin_unlock_irqrestore(&runtime->lock, flags);
1124 	return result;
1125 }
1126 EXPORT_SYMBOL(snd_rawmidi_receive);
1127 
1128 static long snd_rawmidi_kernel_read1(struct snd_rawmidi_substream *substream,
1129 				     unsigned char __user *userbuf,
1130 				     unsigned char *kernelbuf, long count)
1131 {
1132 	unsigned long flags;
1133 	long result = 0, count1;
1134 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1135 	unsigned long appl_ptr;
1136 	int err = 0;
1137 
1138 	spin_lock_irqsave(&runtime->lock, flags);
1139 	snd_rawmidi_buffer_ref(runtime);
1140 	while (count > 0 && runtime->avail) {
1141 		count1 = runtime->buffer_size - runtime->appl_ptr;
1142 		if (count1 > count)
1143 			count1 = count;
1144 		if (count1 > (int)runtime->avail)
1145 			count1 = runtime->avail;
1146 
1147 		/* update runtime->appl_ptr before unlocking for userbuf */
1148 		appl_ptr = runtime->appl_ptr;
1149 		runtime->appl_ptr += count1;
1150 		runtime->appl_ptr %= runtime->buffer_size;
1151 		runtime->avail -= count1;
1152 
1153 		if (kernelbuf)
1154 			memcpy(kernelbuf + result, runtime->buffer + appl_ptr, count1);
1155 		if (userbuf) {
1156 			spin_unlock_irqrestore(&runtime->lock, flags);
1157 			if (copy_to_user(userbuf + result,
1158 					 runtime->buffer + appl_ptr, count1))
1159 				err = -EFAULT;
1160 			spin_lock_irqsave(&runtime->lock, flags);
1161 			if (err)
1162 				goto out;
1163 		}
1164 		result += count1;
1165 		count -= count1;
1166 	}
1167  out:
1168 	snd_rawmidi_buffer_unref(runtime);
1169 	spin_unlock_irqrestore(&runtime->lock, flags);
1170 	return result > 0 ? result : err;
1171 }
1172 
1173 long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
1174 			     unsigned char *buf, long count)
1175 {
1176 	snd_rawmidi_input_trigger(substream, 1);
1177 	return snd_rawmidi_kernel_read1(substream, NULL/*userbuf*/, buf, count);
1178 }
1179 EXPORT_SYMBOL(snd_rawmidi_kernel_read);
1180 
1181 static ssize_t snd_rawmidi_read(struct file *file, char __user *buf, size_t count,
1182 				loff_t *offset)
1183 {
1184 	long result;
1185 	int count1;
1186 	struct snd_rawmidi_file *rfile;
1187 	struct snd_rawmidi_substream *substream;
1188 	struct snd_rawmidi_runtime *runtime;
1189 
1190 	rfile = file->private_data;
1191 	substream = rfile->input;
1192 	if (substream == NULL)
1193 		return -EIO;
1194 	runtime = substream->runtime;
1195 	snd_rawmidi_input_trigger(substream, 1);
1196 	result = 0;
1197 	while (count > 0) {
1198 		spin_lock_irq(&runtime->lock);
1199 		while (!__snd_rawmidi_ready(runtime)) {
1200 			wait_queue_entry_t wait;
1201 
1202 			if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1203 				spin_unlock_irq(&runtime->lock);
1204 				return result > 0 ? result : -EAGAIN;
1205 			}
1206 			init_waitqueue_entry(&wait, current);
1207 			add_wait_queue(&runtime->sleep, &wait);
1208 			set_current_state(TASK_INTERRUPTIBLE);
1209 			spin_unlock_irq(&runtime->lock);
1210 			schedule();
1211 			remove_wait_queue(&runtime->sleep, &wait);
1212 			if (rfile->rmidi->card->shutdown)
1213 				return -ENODEV;
1214 			if (signal_pending(current))
1215 				return result > 0 ? result : -ERESTARTSYS;
1216 			spin_lock_irq(&runtime->lock);
1217 			if (!runtime->avail) {
1218 				spin_unlock_irq(&runtime->lock);
1219 				return result > 0 ? result : -EIO;
1220 			}
1221 		}
1222 		spin_unlock_irq(&runtime->lock);
1223 		count1 = snd_rawmidi_kernel_read1(substream,
1224 						  (unsigned char __user *)buf,
1225 						  NULL/*kernelbuf*/,
1226 						  count);
1227 		if (count1 < 0)
1228 			return result > 0 ? result : count1;
1229 		result += count1;
1230 		buf += count1;
1231 		count -= count1;
1232 	}
1233 	return result;
1234 }
1235 
1236 /**
1237  * snd_rawmidi_transmit_empty - check whether the output buffer is empty
1238  * @substream: the rawmidi substream
1239  *
1240  * Return: 1 if the internal output buffer is empty, 0 if not.
1241  */
1242 int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream)
1243 {
1244 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1245 	int result;
1246 	unsigned long flags;
1247 
1248 	if (runtime->buffer == NULL) {
1249 		rmidi_dbg(substream->rmidi,
1250 			  "snd_rawmidi_transmit_empty: output is not active!!!\n");
1251 		return 1;
1252 	}
1253 	spin_lock_irqsave(&runtime->lock, flags);
1254 	result = runtime->avail >= runtime->buffer_size;
1255 	spin_unlock_irqrestore(&runtime->lock, flags);
1256 	return result;
1257 }
1258 EXPORT_SYMBOL(snd_rawmidi_transmit_empty);
1259 
1260 /**
1261  * __snd_rawmidi_transmit_peek - copy data from the internal buffer
1262  * @substream: the rawmidi substream
1263  * @buffer: the buffer pointer
1264  * @count: data size to transfer
1265  *
1266  * This is a variant of snd_rawmidi_transmit_peek() without spinlock.
1267  */
1268 int __snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
1269 			      unsigned char *buffer, int count)
1270 {
1271 	int result, count1;
1272 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1273 
1274 	if (runtime->buffer == NULL) {
1275 		rmidi_dbg(substream->rmidi,
1276 			  "snd_rawmidi_transmit_peek: output is not active!!!\n");
1277 		return -EINVAL;
1278 	}
1279 	result = 0;
1280 	if (runtime->avail >= runtime->buffer_size) {
1281 		/* warning: lowlevel layer MUST trigger down the hardware */
1282 		goto __skip;
1283 	}
1284 	if (count == 1) {	/* special case, faster code */
1285 		*buffer = runtime->buffer[runtime->hw_ptr];
1286 		result++;
1287 	} else {
1288 		count1 = runtime->buffer_size - runtime->hw_ptr;
1289 		if (count1 > count)
1290 			count1 = count;
1291 		if (count1 > (int)(runtime->buffer_size - runtime->avail))
1292 			count1 = runtime->buffer_size - runtime->avail;
1293 		memcpy(buffer, runtime->buffer + runtime->hw_ptr, count1);
1294 		count -= count1;
1295 		result += count1;
1296 		if (count > 0) {
1297 			if (count > (int)(runtime->buffer_size - runtime->avail - count1))
1298 				count = runtime->buffer_size - runtime->avail - count1;
1299 			memcpy(buffer + count1, runtime->buffer, count);
1300 			result += count;
1301 		}
1302 	}
1303       __skip:
1304 	return result;
1305 }
1306 EXPORT_SYMBOL(__snd_rawmidi_transmit_peek);
1307 
1308 /**
1309  * snd_rawmidi_transmit_peek - copy data from the internal buffer
1310  * @substream: the rawmidi substream
1311  * @buffer: the buffer pointer
1312  * @count: data size to transfer
1313  *
1314  * Copies data from the internal output buffer to the given buffer.
1315  *
1316  * Call this in the interrupt handler when the midi output is ready,
1317  * and call snd_rawmidi_transmit_ack() after the transmission is
1318  * finished.
1319  *
1320  * Return: The size of copied data, or a negative error code on failure.
1321  */
1322 int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
1323 			      unsigned char *buffer, int count)
1324 {
1325 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1326 	int result;
1327 	unsigned long flags;
1328 
1329 	spin_lock_irqsave(&runtime->lock, flags);
1330 	result = __snd_rawmidi_transmit_peek(substream, buffer, count);
1331 	spin_unlock_irqrestore(&runtime->lock, flags);
1332 	return result;
1333 }
1334 EXPORT_SYMBOL(snd_rawmidi_transmit_peek);
1335 
1336 /**
1337  * __snd_rawmidi_transmit_ack - acknowledge the transmission
1338  * @substream: the rawmidi substream
1339  * @count: the transferred count
1340  *
1341  * This is a variant of __snd_rawmidi_transmit_ack() without spinlock.
1342  */
1343 int __snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count)
1344 {
1345 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1346 
1347 	if (runtime->buffer == NULL) {
1348 		rmidi_dbg(substream->rmidi,
1349 			  "snd_rawmidi_transmit_ack: output is not active!!!\n");
1350 		return -EINVAL;
1351 	}
1352 	snd_BUG_ON(runtime->avail + count > runtime->buffer_size);
1353 	runtime->hw_ptr += count;
1354 	runtime->hw_ptr %= runtime->buffer_size;
1355 	runtime->avail += count;
1356 	substream->bytes += count;
1357 	if (count > 0) {
1358 		if (runtime->drain || __snd_rawmidi_ready(runtime))
1359 			wake_up(&runtime->sleep);
1360 	}
1361 	return count;
1362 }
1363 EXPORT_SYMBOL(__snd_rawmidi_transmit_ack);
1364 
1365 /**
1366  * snd_rawmidi_transmit_ack - acknowledge the transmission
1367  * @substream: the rawmidi substream
1368  * @count: the transferred count
1369  *
1370  * Advances the hardware pointer for the internal output buffer with
1371  * the given size and updates the condition.
1372  * Call after the transmission is finished.
1373  *
1374  * Return: The advanced size if successful, or a negative error code on failure.
1375  */
1376 int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count)
1377 {
1378 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1379 	int result;
1380 	unsigned long flags;
1381 
1382 	spin_lock_irqsave(&runtime->lock, flags);
1383 	result = __snd_rawmidi_transmit_ack(substream, count);
1384 	spin_unlock_irqrestore(&runtime->lock, flags);
1385 	return result;
1386 }
1387 EXPORT_SYMBOL(snd_rawmidi_transmit_ack);
1388 
1389 /**
1390  * snd_rawmidi_transmit - copy from the buffer to the device
1391  * @substream: the rawmidi substream
1392  * @buffer: the buffer pointer
1393  * @count: the data size to transfer
1394  *
1395  * Copies data from the buffer to the device and advances the pointer.
1396  *
1397  * Return: The copied size if successful, or a negative error code on failure.
1398  */
1399 int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
1400 			 unsigned char *buffer, int count)
1401 {
1402 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1403 	int result;
1404 	unsigned long flags;
1405 
1406 	spin_lock_irqsave(&runtime->lock, flags);
1407 	if (!substream->opened)
1408 		result = -EBADFD;
1409 	else {
1410 		count = __snd_rawmidi_transmit_peek(substream, buffer, count);
1411 		if (count <= 0)
1412 			result = count;
1413 		else
1414 			result = __snd_rawmidi_transmit_ack(substream, count);
1415 	}
1416 	spin_unlock_irqrestore(&runtime->lock, flags);
1417 	return result;
1418 }
1419 EXPORT_SYMBOL(snd_rawmidi_transmit);
1420 
1421 /**
1422  * snd_rawmidi_proceed - Discard the all pending bytes and proceed
1423  * @substream: rawmidi substream
1424  *
1425  * Return: the number of discarded bytes
1426  */
1427 int snd_rawmidi_proceed(struct snd_rawmidi_substream *substream)
1428 {
1429 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1430 	unsigned long flags;
1431 	int count = 0;
1432 
1433 	spin_lock_irqsave(&runtime->lock, flags);
1434 	if (runtime->avail < runtime->buffer_size) {
1435 		count = runtime->buffer_size - runtime->avail;
1436 		__snd_rawmidi_transmit_ack(substream, count);
1437 	}
1438 	spin_unlock_irqrestore(&runtime->lock, flags);
1439 	return count;
1440 }
1441 EXPORT_SYMBOL(snd_rawmidi_proceed);
1442 
1443 static long snd_rawmidi_kernel_write1(struct snd_rawmidi_substream *substream,
1444 				      const unsigned char __user *userbuf,
1445 				      const unsigned char *kernelbuf,
1446 				      long count)
1447 {
1448 	unsigned long flags;
1449 	long count1, result;
1450 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1451 	unsigned long appl_ptr;
1452 
1453 	if (!kernelbuf && !userbuf)
1454 		return -EINVAL;
1455 	if (snd_BUG_ON(!runtime->buffer))
1456 		return -EINVAL;
1457 
1458 	result = 0;
1459 	spin_lock_irqsave(&runtime->lock, flags);
1460 	if (substream->append) {
1461 		if ((long)runtime->avail < count) {
1462 			spin_unlock_irqrestore(&runtime->lock, flags);
1463 			return -EAGAIN;
1464 		}
1465 	}
1466 	snd_rawmidi_buffer_ref(runtime);
1467 	while (count > 0 && runtime->avail > 0) {
1468 		count1 = runtime->buffer_size - runtime->appl_ptr;
1469 		if (count1 > count)
1470 			count1 = count;
1471 		if (count1 > (long)runtime->avail)
1472 			count1 = runtime->avail;
1473 
1474 		/* update runtime->appl_ptr before unlocking for userbuf */
1475 		appl_ptr = runtime->appl_ptr;
1476 		runtime->appl_ptr += count1;
1477 		runtime->appl_ptr %= runtime->buffer_size;
1478 		runtime->avail -= count1;
1479 
1480 		if (kernelbuf)
1481 			memcpy(runtime->buffer + appl_ptr,
1482 			       kernelbuf + result, count1);
1483 		else if (userbuf) {
1484 			spin_unlock_irqrestore(&runtime->lock, flags);
1485 			if (copy_from_user(runtime->buffer + appl_ptr,
1486 					   userbuf + result, count1)) {
1487 				spin_lock_irqsave(&runtime->lock, flags);
1488 				result = result > 0 ? result : -EFAULT;
1489 				goto __end;
1490 			}
1491 			spin_lock_irqsave(&runtime->lock, flags);
1492 		}
1493 		result += count1;
1494 		count -= count1;
1495 	}
1496       __end:
1497 	count1 = runtime->avail < runtime->buffer_size;
1498 	snd_rawmidi_buffer_unref(runtime);
1499 	spin_unlock_irqrestore(&runtime->lock, flags);
1500 	if (count1)
1501 		snd_rawmidi_output_trigger(substream, 1);
1502 	return result;
1503 }
1504 
1505 long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
1506 			      const unsigned char *buf, long count)
1507 {
1508 	return snd_rawmidi_kernel_write1(substream, NULL, buf, count);
1509 }
1510 EXPORT_SYMBOL(snd_rawmidi_kernel_write);
1511 
1512 static ssize_t snd_rawmidi_write(struct file *file, const char __user *buf,
1513 				 size_t count, loff_t *offset)
1514 {
1515 	long result, timeout;
1516 	int count1;
1517 	struct snd_rawmidi_file *rfile;
1518 	struct snd_rawmidi_runtime *runtime;
1519 	struct snd_rawmidi_substream *substream;
1520 
1521 	rfile = file->private_data;
1522 	substream = rfile->output;
1523 	runtime = substream->runtime;
1524 	/* we cannot put an atomic message to our buffer */
1525 	if (substream->append && count > runtime->buffer_size)
1526 		return -EIO;
1527 	result = 0;
1528 	while (count > 0) {
1529 		spin_lock_irq(&runtime->lock);
1530 		while (!snd_rawmidi_ready_append(substream, count)) {
1531 			wait_queue_entry_t wait;
1532 
1533 			if (file->f_flags & O_NONBLOCK) {
1534 				spin_unlock_irq(&runtime->lock);
1535 				return result > 0 ? result : -EAGAIN;
1536 			}
1537 			init_waitqueue_entry(&wait, current);
1538 			add_wait_queue(&runtime->sleep, &wait);
1539 			set_current_state(TASK_INTERRUPTIBLE);
1540 			spin_unlock_irq(&runtime->lock);
1541 			timeout = schedule_timeout(30 * HZ);
1542 			remove_wait_queue(&runtime->sleep, &wait);
1543 			if (rfile->rmidi->card->shutdown)
1544 				return -ENODEV;
1545 			if (signal_pending(current))
1546 				return result > 0 ? result : -ERESTARTSYS;
1547 			spin_lock_irq(&runtime->lock);
1548 			if (!runtime->avail && !timeout) {
1549 				spin_unlock_irq(&runtime->lock);
1550 				return result > 0 ? result : -EIO;
1551 			}
1552 		}
1553 		spin_unlock_irq(&runtime->lock);
1554 		count1 = snd_rawmidi_kernel_write1(substream, buf, NULL, count);
1555 		if (count1 < 0)
1556 			return result > 0 ? result : count1;
1557 		result += count1;
1558 		buf += count1;
1559 		if ((size_t)count1 < count && (file->f_flags & O_NONBLOCK))
1560 			break;
1561 		count -= count1;
1562 	}
1563 	if (file->f_flags & O_DSYNC) {
1564 		spin_lock_irq(&runtime->lock);
1565 		while (runtime->avail != runtime->buffer_size) {
1566 			wait_queue_entry_t wait;
1567 			unsigned int last_avail = runtime->avail;
1568 
1569 			init_waitqueue_entry(&wait, current);
1570 			add_wait_queue(&runtime->sleep, &wait);
1571 			set_current_state(TASK_INTERRUPTIBLE);
1572 			spin_unlock_irq(&runtime->lock);
1573 			timeout = schedule_timeout(30 * HZ);
1574 			remove_wait_queue(&runtime->sleep, &wait);
1575 			if (signal_pending(current))
1576 				return result > 0 ? result : -ERESTARTSYS;
1577 			if (runtime->avail == last_avail && !timeout)
1578 				return result > 0 ? result : -EIO;
1579 			spin_lock_irq(&runtime->lock);
1580 		}
1581 		spin_unlock_irq(&runtime->lock);
1582 	}
1583 	return result;
1584 }
1585 
1586 static __poll_t snd_rawmidi_poll(struct file *file, poll_table *wait)
1587 {
1588 	struct snd_rawmidi_file *rfile;
1589 	struct snd_rawmidi_runtime *runtime;
1590 	__poll_t mask;
1591 
1592 	rfile = file->private_data;
1593 	if (rfile->input != NULL) {
1594 		runtime = rfile->input->runtime;
1595 		snd_rawmidi_input_trigger(rfile->input, 1);
1596 		poll_wait(file, &runtime->sleep, wait);
1597 	}
1598 	if (rfile->output != NULL) {
1599 		runtime = rfile->output->runtime;
1600 		poll_wait(file, &runtime->sleep, wait);
1601 	}
1602 	mask = 0;
1603 	if (rfile->input != NULL) {
1604 		if (snd_rawmidi_ready(rfile->input))
1605 			mask |= EPOLLIN | EPOLLRDNORM;
1606 	}
1607 	if (rfile->output != NULL) {
1608 		if (snd_rawmidi_ready(rfile->output))
1609 			mask |= EPOLLOUT | EPOLLWRNORM;
1610 	}
1611 	return mask;
1612 }
1613 
1614 /*
1615  */
1616 #ifdef CONFIG_COMPAT
1617 #include "rawmidi_compat.c"
1618 #else
1619 #define snd_rawmidi_ioctl_compat	NULL
1620 #endif
1621 
1622 /*
1623  */
1624 
1625 static void snd_rawmidi_proc_info_read(struct snd_info_entry *entry,
1626 				       struct snd_info_buffer *buffer)
1627 {
1628 	struct snd_rawmidi *rmidi;
1629 	struct snd_rawmidi_substream *substream;
1630 	struct snd_rawmidi_runtime *runtime;
1631 	unsigned long buffer_size, avail, xruns;
1632 	unsigned int clock_type;
1633 	static const char *clock_names[4] = { "none", "realtime", "monotonic", "monotonic raw" };
1634 
1635 	rmidi = entry->private_data;
1636 	snd_iprintf(buffer, "%s\n\n", rmidi->name);
1637 	mutex_lock(&rmidi->open_mutex);
1638 	if (rmidi->info_flags & SNDRV_RAWMIDI_INFO_OUTPUT) {
1639 		list_for_each_entry(substream,
1640 				    &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams,
1641 				    list) {
1642 			snd_iprintf(buffer,
1643 				    "Output %d\n"
1644 				    "  Tx bytes     : %lu\n",
1645 				    substream->number,
1646 				    (unsigned long) substream->bytes);
1647 			if (substream->opened) {
1648 				snd_iprintf(buffer,
1649 				    "  Owner PID    : %d\n",
1650 				    pid_vnr(substream->pid));
1651 				runtime = substream->runtime;
1652 				spin_lock_irq(&runtime->lock);
1653 				buffer_size = runtime->buffer_size;
1654 				avail = runtime->avail;
1655 				spin_unlock_irq(&runtime->lock);
1656 				snd_iprintf(buffer,
1657 				    "  Mode         : %s\n"
1658 				    "  Buffer size  : %lu\n"
1659 				    "  Avail        : %lu\n",
1660 				    runtime->oss ? "OSS compatible" : "native",
1661 				    buffer_size, avail);
1662 			}
1663 		}
1664 	}
1665 	if (rmidi->info_flags & SNDRV_RAWMIDI_INFO_INPUT) {
1666 		list_for_each_entry(substream,
1667 				    &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams,
1668 				    list) {
1669 			snd_iprintf(buffer,
1670 				    "Input %d\n"
1671 				    "  Rx bytes     : %lu\n",
1672 				    substream->number,
1673 				    (unsigned long) substream->bytes);
1674 			if (substream->opened) {
1675 				snd_iprintf(buffer,
1676 					    "  Owner PID    : %d\n",
1677 					    pid_vnr(substream->pid));
1678 				runtime = substream->runtime;
1679 				spin_lock_irq(&runtime->lock);
1680 				buffer_size = runtime->buffer_size;
1681 				avail = runtime->avail;
1682 				xruns = runtime->xruns;
1683 				spin_unlock_irq(&runtime->lock);
1684 				snd_iprintf(buffer,
1685 					    "  Buffer size  : %lu\n"
1686 					    "  Avail        : %lu\n"
1687 					    "  Overruns     : %lu\n",
1688 					    buffer_size, avail, xruns);
1689 				if (substream->framing == SNDRV_RAWMIDI_MODE_FRAMING_TSTAMP) {
1690 					clock_type = substream->clock_type >> SNDRV_RAWMIDI_MODE_CLOCK_SHIFT;
1691 					if (!snd_BUG_ON(clock_type >= ARRAY_SIZE(clock_names)))
1692 						snd_iprintf(buffer,
1693 							    "  Framing      : tstamp\n"
1694 							    "  Clock type   : %s\n",
1695 							    clock_names[clock_type]);
1696 				}
1697 			}
1698 		}
1699 	}
1700 	mutex_unlock(&rmidi->open_mutex);
1701 }
1702 
1703 /*
1704  *  Register functions
1705  */
1706 
1707 static const struct file_operations snd_rawmidi_f_ops = {
1708 	.owner =	THIS_MODULE,
1709 	.read =		snd_rawmidi_read,
1710 	.write =	snd_rawmidi_write,
1711 	.open =		snd_rawmidi_open,
1712 	.release =	snd_rawmidi_release,
1713 	.llseek =	no_llseek,
1714 	.poll =		snd_rawmidi_poll,
1715 	.unlocked_ioctl =	snd_rawmidi_ioctl,
1716 	.compat_ioctl =	snd_rawmidi_ioctl_compat,
1717 };
1718 
1719 static int snd_rawmidi_alloc_substreams(struct snd_rawmidi *rmidi,
1720 					struct snd_rawmidi_str *stream,
1721 					int direction,
1722 					int count)
1723 {
1724 	struct snd_rawmidi_substream *substream;
1725 	int idx;
1726 
1727 	for (idx = 0; idx < count; idx++) {
1728 		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
1729 		if (!substream)
1730 			return -ENOMEM;
1731 		substream->stream = direction;
1732 		substream->number = idx;
1733 		substream->rmidi = rmidi;
1734 		substream->pstr = stream;
1735 		list_add_tail(&substream->list, &stream->substreams);
1736 		stream->substream_count++;
1737 	}
1738 	return 0;
1739 }
1740 
1741 static void release_rawmidi_device(struct device *dev)
1742 {
1743 	kfree(container_of(dev, struct snd_rawmidi, dev));
1744 }
1745 
1746 /**
1747  * snd_rawmidi_new - create a rawmidi instance
1748  * @card: the card instance
1749  * @id: the id string
1750  * @device: the device index
1751  * @output_count: the number of output streams
1752  * @input_count: the number of input streams
1753  * @rrawmidi: the pointer to store the new rawmidi instance
1754  *
1755  * Creates a new rawmidi instance.
1756  * Use snd_rawmidi_set_ops() to set the operators to the new instance.
1757  *
1758  * Return: Zero if successful, or a negative error code on failure.
1759  */
1760 int snd_rawmidi_new(struct snd_card *card, char *id, int device,
1761 		    int output_count, int input_count,
1762 		    struct snd_rawmidi **rrawmidi)
1763 {
1764 	struct snd_rawmidi *rmidi;
1765 	int err;
1766 	static const struct snd_device_ops ops = {
1767 		.dev_free = snd_rawmidi_dev_free,
1768 		.dev_register = snd_rawmidi_dev_register,
1769 		.dev_disconnect = snd_rawmidi_dev_disconnect,
1770 	};
1771 
1772 	if (snd_BUG_ON(!card))
1773 		return -ENXIO;
1774 	if (rrawmidi)
1775 		*rrawmidi = NULL;
1776 	rmidi = kzalloc(sizeof(*rmidi), GFP_KERNEL);
1777 	if (!rmidi)
1778 		return -ENOMEM;
1779 	rmidi->card = card;
1780 	rmidi->device = device;
1781 	mutex_init(&rmidi->open_mutex);
1782 	init_waitqueue_head(&rmidi->open_wait);
1783 	INIT_LIST_HEAD(&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams);
1784 	INIT_LIST_HEAD(&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams);
1785 
1786 	if (id != NULL)
1787 		strscpy(rmidi->id, id, sizeof(rmidi->id));
1788 
1789 	snd_device_initialize(&rmidi->dev, card);
1790 	rmidi->dev.release = release_rawmidi_device;
1791 	dev_set_name(&rmidi->dev, "midiC%iD%i", card->number, device);
1792 
1793 	err = snd_rawmidi_alloc_substreams(rmidi,
1794 					   &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT],
1795 					   SNDRV_RAWMIDI_STREAM_INPUT,
1796 					   input_count);
1797 	if (err < 0)
1798 		goto error;
1799 	err = snd_rawmidi_alloc_substreams(rmidi,
1800 					   &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT],
1801 					   SNDRV_RAWMIDI_STREAM_OUTPUT,
1802 					   output_count);
1803 	if (err < 0)
1804 		goto error;
1805 	err = snd_device_new(card, SNDRV_DEV_RAWMIDI, rmidi, &ops);
1806 	if (err < 0)
1807 		goto error;
1808 
1809 	if (rrawmidi)
1810 		*rrawmidi = rmidi;
1811 	return 0;
1812 
1813  error:
1814 	snd_rawmidi_free(rmidi);
1815 	return err;
1816 }
1817 EXPORT_SYMBOL(snd_rawmidi_new);
1818 
1819 static void snd_rawmidi_free_substreams(struct snd_rawmidi_str *stream)
1820 {
1821 	struct snd_rawmidi_substream *substream;
1822 
1823 	while (!list_empty(&stream->substreams)) {
1824 		substream = list_entry(stream->substreams.next, struct snd_rawmidi_substream, list);
1825 		list_del(&substream->list);
1826 		kfree(substream);
1827 	}
1828 }
1829 
1830 static int snd_rawmidi_free(struct snd_rawmidi *rmidi)
1831 {
1832 	if (!rmidi)
1833 		return 0;
1834 
1835 	snd_info_free_entry(rmidi->proc_entry);
1836 	rmidi->proc_entry = NULL;
1837 	mutex_lock(&register_mutex);
1838 	if (rmidi->ops && rmidi->ops->dev_unregister)
1839 		rmidi->ops->dev_unregister(rmidi);
1840 	mutex_unlock(&register_mutex);
1841 
1842 	snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
1843 	snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
1844 	if (rmidi->private_free)
1845 		rmidi->private_free(rmidi);
1846 	put_device(&rmidi->dev);
1847 	return 0;
1848 }
1849 
1850 static int snd_rawmidi_dev_free(struct snd_device *device)
1851 {
1852 	struct snd_rawmidi *rmidi = device->device_data;
1853 
1854 	return snd_rawmidi_free(rmidi);
1855 }
1856 
1857 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
1858 static void snd_rawmidi_dev_seq_free(struct snd_seq_device *device)
1859 {
1860 	struct snd_rawmidi *rmidi = device->private_data;
1861 
1862 	rmidi->seq_dev = NULL;
1863 }
1864 #endif
1865 
1866 static int snd_rawmidi_dev_register(struct snd_device *device)
1867 {
1868 	int err;
1869 	struct snd_info_entry *entry;
1870 	char name[16];
1871 	struct snd_rawmidi *rmidi = device->device_data;
1872 
1873 	if (rmidi->device >= SNDRV_RAWMIDI_DEVICES)
1874 		return -ENOMEM;
1875 	err = 0;
1876 	mutex_lock(&register_mutex);
1877 	if (snd_rawmidi_search(rmidi->card, rmidi->device))
1878 		err = -EBUSY;
1879 	else
1880 		list_add_tail(&rmidi->list, &snd_rawmidi_devices);
1881 	mutex_unlock(&register_mutex);
1882 	if (err < 0)
1883 		return err;
1884 
1885 	err = snd_register_device(SNDRV_DEVICE_TYPE_RAWMIDI,
1886 				  rmidi->card, rmidi->device,
1887 				  &snd_rawmidi_f_ops, rmidi, &rmidi->dev);
1888 	if (err < 0) {
1889 		rmidi_err(rmidi, "unable to register\n");
1890 		goto error;
1891 	}
1892 	if (rmidi->ops && rmidi->ops->dev_register) {
1893 		err = rmidi->ops->dev_register(rmidi);
1894 		if (err < 0)
1895 			goto error_unregister;
1896 	}
1897 #ifdef CONFIG_SND_OSSEMUL
1898 	rmidi->ossreg = 0;
1899 	if ((int)rmidi->device == midi_map[rmidi->card->number]) {
1900 		if (snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI,
1901 					    rmidi->card, 0, &snd_rawmidi_f_ops,
1902 					    rmidi) < 0) {
1903 			rmidi_err(rmidi,
1904 				  "unable to register OSS rawmidi device %i:%i\n",
1905 				  rmidi->card->number, 0);
1906 		} else {
1907 			rmidi->ossreg++;
1908 #ifdef SNDRV_OSS_INFO_DEV_MIDI
1909 			snd_oss_info_register(SNDRV_OSS_INFO_DEV_MIDI, rmidi->card->number, rmidi->name);
1910 #endif
1911 		}
1912 	}
1913 	if ((int)rmidi->device == amidi_map[rmidi->card->number]) {
1914 		if (snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI,
1915 					    rmidi->card, 1, &snd_rawmidi_f_ops,
1916 					    rmidi) < 0) {
1917 			rmidi_err(rmidi,
1918 				  "unable to register OSS rawmidi device %i:%i\n",
1919 				  rmidi->card->number, 1);
1920 		} else {
1921 			rmidi->ossreg++;
1922 		}
1923 	}
1924 #endif /* CONFIG_SND_OSSEMUL */
1925 	sprintf(name, "midi%d", rmidi->device);
1926 	entry = snd_info_create_card_entry(rmidi->card, name, rmidi->card->proc_root);
1927 	if (entry) {
1928 		entry->private_data = rmidi;
1929 		entry->c.text.read = snd_rawmidi_proc_info_read;
1930 		if (snd_info_register(entry) < 0) {
1931 			snd_info_free_entry(entry);
1932 			entry = NULL;
1933 		}
1934 	}
1935 	rmidi->proc_entry = entry;
1936 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
1937 	if (!rmidi->ops || !rmidi->ops->dev_register) { /* own registration mechanism */
1938 		if (snd_seq_device_new(rmidi->card, rmidi->device, SNDRV_SEQ_DEV_ID_MIDISYNTH, 0, &rmidi->seq_dev) >= 0) {
1939 			rmidi->seq_dev->private_data = rmidi;
1940 			rmidi->seq_dev->private_free = snd_rawmidi_dev_seq_free;
1941 			sprintf(rmidi->seq_dev->name, "MIDI %d-%d", rmidi->card->number, rmidi->device);
1942 			snd_device_register(rmidi->card, rmidi->seq_dev);
1943 		}
1944 	}
1945 #endif
1946 	return 0;
1947 
1948  error_unregister:
1949 	snd_unregister_device(&rmidi->dev);
1950  error:
1951 	mutex_lock(&register_mutex);
1952 	list_del(&rmidi->list);
1953 	mutex_unlock(&register_mutex);
1954 	return err;
1955 }
1956 
1957 static int snd_rawmidi_dev_disconnect(struct snd_device *device)
1958 {
1959 	struct snd_rawmidi *rmidi = device->device_data;
1960 	int dir;
1961 
1962 	mutex_lock(&register_mutex);
1963 	mutex_lock(&rmidi->open_mutex);
1964 	wake_up(&rmidi->open_wait);
1965 	list_del_init(&rmidi->list);
1966 	for (dir = 0; dir < 2; dir++) {
1967 		struct snd_rawmidi_substream *s;
1968 
1969 		list_for_each_entry(s, &rmidi->streams[dir].substreams, list) {
1970 			if (s->runtime)
1971 				wake_up(&s->runtime->sleep);
1972 		}
1973 	}
1974 
1975 #ifdef CONFIG_SND_OSSEMUL
1976 	if (rmidi->ossreg) {
1977 		if ((int)rmidi->device == midi_map[rmidi->card->number]) {
1978 			snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI, rmidi->card, 0);
1979 #ifdef SNDRV_OSS_INFO_DEV_MIDI
1980 			snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_MIDI, rmidi->card->number);
1981 #endif
1982 		}
1983 		if ((int)rmidi->device == amidi_map[rmidi->card->number])
1984 			snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI, rmidi->card, 1);
1985 		rmidi->ossreg = 0;
1986 	}
1987 #endif /* CONFIG_SND_OSSEMUL */
1988 	snd_unregister_device(&rmidi->dev);
1989 	mutex_unlock(&rmidi->open_mutex);
1990 	mutex_unlock(&register_mutex);
1991 	return 0;
1992 }
1993 
1994 /**
1995  * snd_rawmidi_set_ops - set the rawmidi operators
1996  * @rmidi: the rawmidi instance
1997  * @stream: the stream direction, SNDRV_RAWMIDI_STREAM_XXX
1998  * @ops: the operator table
1999  *
2000  * Sets the rawmidi operators for the given stream direction.
2001  */
2002 void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream,
2003 			 const struct snd_rawmidi_ops *ops)
2004 {
2005 	struct snd_rawmidi_substream *substream;
2006 
2007 	list_for_each_entry(substream, &rmidi->streams[stream].substreams, list)
2008 		substream->ops = ops;
2009 }
2010 EXPORT_SYMBOL(snd_rawmidi_set_ops);
2011 
2012 /*
2013  *  ENTRY functions
2014  */
2015 
2016 static int __init alsa_rawmidi_init(void)
2017 {
2018 
2019 	snd_ctl_register_ioctl(snd_rawmidi_control_ioctl);
2020 	snd_ctl_register_ioctl_compat(snd_rawmidi_control_ioctl);
2021 #ifdef CONFIG_SND_OSSEMUL
2022 	{ int i;
2023 	/* check device map table */
2024 	for (i = 0; i < SNDRV_CARDS; i++) {
2025 		if (midi_map[i] < 0 || midi_map[i] >= SNDRV_RAWMIDI_DEVICES) {
2026 			pr_err("ALSA: rawmidi: invalid midi_map[%d] = %d\n",
2027 			       i, midi_map[i]);
2028 			midi_map[i] = 0;
2029 		}
2030 		if (amidi_map[i] < 0 || amidi_map[i] >= SNDRV_RAWMIDI_DEVICES) {
2031 			pr_err("ALSA: rawmidi: invalid amidi_map[%d] = %d\n",
2032 			       i, amidi_map[i]);
2033 			amidi_map[i] = 1;
2034 		}
2035 	}
2036 	}
2037 #endif /* CONFIG_SND_OSSEMUL */
2038 	return 0;
2039 }
2040 
2041 static void __exit alsa_rawmidi_exit(void)
2042 {
2043 	snd_ctl_unregister_ioctl(snd_rawmidi_control_ioctl);
2044 	snd_ctl_unregister_ioctl_compat(snd_rawmidi_control_ioctl);
2045 }
2046 
2047 module_init(alsa_rawmidi_init)
2048 module_exit(alsa_rawmidi_exit)
2049