xref: /openbmc/linux/sound/core/rawmidi.c (revision 711aab1d)
1 /*
2  *  Abstract layer for MIDI v1.0 stream
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4  *
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *   GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program; if not, write to the Free Software
18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
19  *
20  */
21 
22 #include <sound/core.h>
23 #include <linux/major.h>
24 #include <linux/init.h>
25 #include <linux/sched/signal.h>
26 #include <linux/slab.h>
27 #include <linux/time.h>
28 #include <linux/wait.h>
29 #include <linux/mutex.h>
30 #include <linux/module.h>
31 #include <linux/delay.h>
32 #include <sound/rawmidi.h>
33 #include <sound/info.h>
34 #include <sound/control.h>
35 #include <sound/minors.h>
36 #include <sound/initval.h>
37 
38 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
39 MODULE_DESCRIPTION("Midlevel RawMidi code for ALSA.");
40 MODULE_LICENSE("GPL");
41 
42 #ifdef CONFIG_SND_OSSEMUL
43 static int midi_map[SNDRV_CARDS];
44 static int amidi_map[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = 1};
45 module_param_array(midi_map, int, NULL, 0444);
46 MODULE_PARM_DESC(midi_map, "Raw MIDI device number assigned to 1st OSS device.");
47 module_param_array(amidi_map, int, NULL, 0444);
48 MODULE_PARM_DESC(amidi_map, "Raw MIDI device number assigned to 2nd OSS device.");
49 #endif /* CONFIG_SND_OSSEMUL */
50 
51 static int snd_rawmidi_free(struct snd_rawmidi *rawmidi);
52 static int snd_rawmidi_dev_free(struct snd_device *device);
53 static int snd_rawmidi_dev_register(struct snd_device *device);
54 static int snd_rawmidi_dev_disconnect(struct snd_device *device);
55 
56 static LIST_HEAD(snd_rawmidi_devices);
57 static DEFINE_MUTEX(register_mutex);
58 
59 #define rmidi_err(rmidi, fmt, args...) \
60 	dev_err(&(rmidi)->dev, fmt, ##args)
61 #define rmidi_warn(rmidi, fmt, args...) \
62 	dev_warn(&(rmidi)->dev, fmt, ##args)
63 #define rmidi_dbg(rmidi, fmt, args...) \
64 	dev_dbg(&(rmidi)->dev, fmt, ##args)
65 
66 static struct snd_rawmidi *snd_rawmidi_search(struct snd_card *card, int device)
67 {
68 	struct snd_rawmidi *rawmidi;
69 
70 	list_for_each_entry(rawmidi, &snd_rawmidi_devices, list)
71 		if (rawmidi->card == card && rawmidi->device == device)
72 			return rawmidi;
73 	return NULL;
74 }
75 
76 static inline unsigned short snd_rawmidi_file_flags(struct file *file)
77 {
78 	switch (file->f_mode & (FMODE_READ | FMODE_WRITE)) {
79 	case FMODE_WRITE:
80 		return SNDRV_RAWMIDI_LFLG_OUTPUT;
81 	case FMODE_READ:
82 		return SNDRV_RAWMIDI_LFLG_INPUT;
83 	default:
84 		return SNDRV_RAWMIDI_LFLG_OPEN;
85 	}
86 }
87 
88 static inline int snd_rawmidi_ready(struct snd_rawmidi_substream *substream)
89 {
90 	struct snd_rawmidi_runtime *runtime = substream->runtime;
91 	return runtime->avail >= runtime->avail_min;
92 }
93 
94 static inline int snd_rawmidi_ready_append(struct snd_rawmidi_substream *substream,
95 					   size_t count)
96 {
97 	struct snd_rawmidi_runtime *runtime = substream->runtime;
98 	return runtime->avail >= runtime->avail_min &&
99 	       (!substream->append || runtime->avail >= count);
100 }
101 
102 static void snd_rawmidi_input_event_work(struct work_struct *work)
103 {
104 	struct snd_rawmidi_runtime *runtime =
105 		container_of(work, struct snd_rawmidi_runtime, event_work);
106 	if (runtime->event)
107 		runtime->event(runtime->substream);
108 }
109 
110 static int snd_rawmidi_runtime_create(struct snd_rawmidi_substream *substream)
111 {
112 	struct snd_rawmidi_runtime *runtime;
113 
114 	if ((runtime = kzalloc(sizeof(*runtime), GFP_KERNEL)) == NULL)
115 		return -ENOMEM;
116 	runtime->substream = substream;
117 	spin_lock_init(&runtime->lock);
118 	init_waitqueue_head(&runtime->sleep);
119 	INIT_WORK(&runtime->event_work, snd_rawmidi_input_event_work);
120 	runtime->event = NULL;
121 	runtime->buffer_size = PAGE_SIZE;
122 	runtime->avail_min = 1;
123 	if (substream->stream == SNDRV_RAWMIDI_STREAM_INPUT)
124 		runtime->avail = 0;
125 	else
126 		runtime->avail = runtime->buffer_size;
127 	if ((runtime->buffer = kmalloc(runtime->buffer_size, GFP_KERNEL)) == NULL) {
128 		kfree(runtime);
129 		return -ENOMEM;
130 	}
131 	runtime->appl_ptr = runtime->hw_ptr = 0;
132 	substream->runtime = runtime;
133 	return 0;
134 }
135 
136 static int snd_rawmidi_runtime_free(struct snd_rawmidi_substream *substream)
137 {
138 	struct snd_rawmidi_runtime *runtime = substream->runtime;
139 
140 	kfree(runtime->buffer);
141 	kfree(runtime);
142 	substream->runtime = NULL;
143 	return 0;
144 }
145 
146 static inline void snd_rawmidi_output_trigger(struct snd_rawmidi_substream *substream,int up)
147 {
148 	if (!substream->opened)
149 		return;
150 	substream->ops->trigger(substream, up);
151 }
152 
153 static void snd_rawmidi_input_trigger(struct snd_rawmidi_substream *substream, int up)
154 {
155 	if (!substream->opened)
156 		return;
157 	substream->ops->trigger(substream, up);
158 	if (!up)
159 		cancel_work_sync(&substream->runtime->event_work);
160 }
161 
162 int snd_rawmidi_drop_output(struct snd_rawmidi_substream *substream)
163 {
164 	unsigned long flags;
165 	struct snd_rawmidi_runtime *runtime = substream->runtime;
166 
167 	snd_rawmidi_output_trigger(substream, 0);
168 	runtime->drain = 0;
169 	spin_lock_irqsave(&runtime->lock, flags);
170 	runtime->appl_ptr = runtime->hw_ptr = 0;
171 	runtime->avail = runtime->buffer_size;
172 	spin_unlock_irqrestore(&runtime->lock, flags);
173 	return 0;
174 }
175 EXPORT_SYMBOL(snd_rawmidi_drop_output);
176 
177 int snd_rawmidi_drain_output(struct snd_rawmidi_substream *substream)
178 {
179 	int err;
180 	long timeout;
181 	struct snd_rawmidi_runtime *runtime = substream->runtime;
182 
183 	err = 0;
184 	runtime->drain = 1;
185 	timeout = wait_event_interruptible_timeout(runtime->sleep,
186 				(runtime->avail >= runtime->buffer_size),
187 				10*HZ);
188 	if (signal_pending(current))
189 		err = -ERESTARTSYS;
190 	if (runtime->avail < runtime->buffer_size && !timeout) {
191 		rmidi_warn(substream->rmidi,
192 			   "rawmidi drain error (avail = %li, buffer_size = %li)\n",
193 			   (long)runtime->avail, (long)runtime->buffer_size);
194 		err = -EIO;
195 	}
196 	runtime->drain = 0;
197 	if (err != -ERESTARTSYS) {
198 		/* we need wait a while to make sure that Tx FIFOs are empty */
199 		if (substream->ops->drain)
200 			substream->ops->drain(substream);
201 		else
202 			msleep(50);
203 		snd_rawmidi_drop_output(substream);
204 	}
205 	return err;
206 }
207 EXPORT_SYMBOL(snd_rawmidi_drain_output);
208 
209 int snd_rawmidi_drain_input(struct snd_rawmidi_substream *substream)
210 {
211 	unsigned long flags;
212 	struct snd_rawmidi_runtime *runtime = substream->runtime;
213 
214 	snd_rawmidi_input_trigger(substream, 0);
215 	runtime->drain = 0;
216 	spin_lock_irqsave(&runtime->lock, flags);
217 	runtime->appl_ptr = runtime->hw_ptr = 0;
218 	runtime->avail = 0;
219 	spin_unlock_irqrestore(&runtime->lock, flags);
220 	return 0;
221 }
222 EXPORT_SYMBOL(snd_rawmidi_drain_input);
223 
224 /* look for an available substream for the given stream direction;
225  * if a specific subdevice is given, try to assign it
226  */
227 static int assign_substream(struct snd_rawmidi *rmidi, int subdevice,
228 			    int stream, int mode,
229 			    struct snd_rawmidi_substream **sub_ret)
230 {
231 	struct snd_rawmidi_substream *substream;
232 	struct snd_rawmidi_str *s = &rmidi->streams[stream];
233 	static unsigned int info_flags[2] = {
234 		[SNDRV_RAWMIDI_STREAM_OUTPUT] = SNDRV_RAWMIDI_INFO_OUTPUT,
235 		[SNDRV_RAWMIDI_STREAM_INPUT] = SNDRV_RAWMIDI_INFO_INPUT,
236 	};
237 
238 	if (!(rmidi->info_flags & info_flags[stream]))
239 		return -ENXIO;
240 	if (subdevice >= 0 && subdevice >= s->substream_count)
241 		return -ENODEV;
242 
243 	list_for_each_entry(substream, &s->substreams, list) {
244 		if (substream->opened) {
245 			if (stream == SNDRV_RAWMIDI_STREAM_INPUT ||
246 			    !(mode & SNDRV_RAWMIDI_LFLG_APPEND) ||
247 			    !substream->append)
248 				continue;
249 		}
250 		if (subdevice < 0 || subdevice == substream->number) {
251 			*sub_ret = substream;
252 			return 0;
253 		}
254 	}
255 	return -EAGAIN;
256 }
257 
258 /* open and do ref-counting for the given substream */
259 static int open_substream(struct snd_rawmidi *rmidi,
260 			  struct snd_rawmidi_substream *substream,
261 			  int mode)
262 {
263 	int err;
264 
265 	if (substream->use_count == 0) {
266 		err = snd_rawmidi_runtime_create(substream);
267 		if (err < 0)
268 			return err;
269 		err = substream->ops->open(substream);
270 		if (err < 0) {
271 			snd_rawmidi_runtime_free(substream);
272 			return err;
273 		}
274 		substream->opened = 1;
275 		substream->active_sensing = 0;
276 		if (mode & SNDRV_RAWMIDI_LFLG_APPEND)
277 			substream->append = 1;
278 		substream->pid = get_pid(task_pid(current));
279 		rmidi->streams[substream->stream].substream_opened++;
280 	}
281 	substream->use_count++;
282 	return 0;
283 }
284 
285 static void close_substream(struct snd_rawmidi *rmidi,
286 			    struct snd_rawmidi_substream *substream,
287 			    int cleanup);
288 
289 static int rawmidi_open_priv(struct snd_rawmidi *rmidi, int subdevice, int mode,
290 			     struct snd_rawmidi_file *rfile)
291 {
292 	struct snd_rawmidi_substream *sinput = NULL, *soutput = NULL;
293 	int err;
294 
295 	rfile->input = rfile->output = NULL;
296 	if (mode & SNDRV_RAWMIDI_LFLG_INPUT) {
297 		err = assign_substream(rmidi, subdevice,
298 				       SNDRV_RAWMIDI_STREAM_INPUT,
299 				       mode, &sinput);
300 		if (err < 0)
301 			return err;
302 	}
303 	if (mode & SNDRV_RAWMIDI_LFLG_OUTPUT) {
304 		err = assign_substream(rmidi, subdevice,
305 				       SNDRV_RAWMIDI_STREAM_OUTPUT,
306 				       mode, &soutput);
307 		if (err < 0)
308 			return err;
309 	}
310 
311 	if (sinput) {
312 		err = open_substream(rmidi, sinput, mode);
313 		if (err < 0)
314 			return err;
315 	}
316 	if (soutput) {
317 		err = open_substream(rmidi, soutput, mode);
318 		if (err < 0) {
319 			if (sinput)
320 				close_substream(rmidi, sinput, 0);
321 			return err;
322 		}
323 	}
324 
325 	rfile->rmidi = rmidi;
326 	rfile->input = sinput;
327 	rfile->output = soutput;
328 	return 0;
329 }
330 
331 /* called from sound/core/seq/seq_midi.c */
332 int snd_rawmidi_kernel_open(struct snd_card *card, int device, int subdevice,
333 			    int mode, struct snd_rawmidi_file * rfile)
334 {
335 	struct snd_rawmidi *rmidi;
336 	int err;
337 
338 	if (snd_BUG_ON(!rfile))
339 		return -EINVAL;
340 
341 	mutex_lock(&register_mutex);
342 	rmidi = snd_rawmidi_search(card, device);
343 	if (rmidi == NULL) {
344 		mutex_unlock(&register_mutex);
345 		return -ENODEV;
346 	}
347 	if (!try_module_get(rmidi->card->module)) {
348 		mutex_unlock(&register_mutex);
349 		return -ENXIO;
350 	}
351 	mutex_unlock(&register_mutex);
352 
353 	mutex_lock(&rmidi->open_mutex);
354 	err = rawmidi_open_priv(rmidi, subdevice, mode, rfile);
355 	mutex_unlock(&rmidi->open_mutex);
356 	if (err < 0)
357 		module_put(rmidi->card->module);
358 	return err;
359 }
360 EXPORT_SYMBOL(snd_rawmidi_kernel_open);
361 
362 static int snd_rawmidi_open(struct inode *inode, struct file *file)
363 {
364 	int maj = imajor(inode);
365 	struct snd_card *card;
366 	int subdevice;
367 	unsigned short fflags;
368 	int err;
369 	struct snd_rawmidi *rmidi;
370 	struct snd_rawmidi_file *rawmidi_file = NULL;
371 	wait_queue_entry_t wait;
372 
373 	if ((file->f_flags & O_APPEND) && !(file->f_flags & O_NONBLOCK))
374 		return -EINVAL;		/* invalid combination */
375 
376 	err = nonseekable_open(inode, file);
377 	if (err < 0)
378 		return err;
379 
380 	if (maj == snd_major) {
381 		rmidi = snd_lookup_minor_data(iminor(inode),
382 					      SNDRV_DEVICE_TYPE_RAWMIDI);
383 #ifdef CONFIG_SND_OSSEMUL
384 	} else if (maj == SOUND_MAJOR) {
385 		rmidi = snd_lookup_oss_minor_data(iminor(inode),
386 						  SNDRV_OSS_DEVICE_TYPE_MIDI);
387 #endif
388 	} else
389 		return -ENXIO;
390 
391 	if (rmidi == NULL)
392 		return -ENODEV;
393 
394 	if (!try_module_get(rmidi->card->module)) {
395 		snd_card_unref(rmidi->card);
396 		return -ENXIO;
397 	}
398 
399 	mutex_lock(&rmidi->open_mutex);
400 	card = rmidi->card;
401 	err = snd_card_file_add(card, file);
402 	if (err < 0)
403 		goto __error_card;
404 	fflags = snd_rawmidi_file_flags(file);
405 	if ((file->f_flags & O_APPEND) || maj == SOUND_MAJOR) /* OSS emul? */
406 		fflags |= SNDRV_RAWMIDI_LFLG_APPEND;
407 	rawmidi_file = kmalloc(sizeof(*rawmidi_file), GFP_KERNEL);
408 	if (rawmidi_file == NULL) {
409 		err = -ENOMEM;
410 		goto __error;
411 	}
412 	init_waitqueue_entry(&wait, current);
413 	add_wait_queue(&rmidi->open_wait, &wait);
414 	while (1) {
415 		subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_RAWMIDI);
416 		err = rawmidi_open_priv(rmidi, subdevice, fflags, rawmidi_file);
417 		if (err >= 0)
418 			break;
419 		if (err == -EAGAIN) {
420 			if (file->f_flags & O_NONBLOCK) {
421 				err = -EBUSY;
422 				break;
423 			}
424 		} else
425 			break;
426 		set_current_state(TASK_INTERRUPTIBLE);
427 		mutex_unlock(&rmidi->open_mutex);
428 		schedule();
429 		mutex_lock(&rmidi->open_mutex);
430 		if (rmidi->card->shutdown) {
431 			err = -ENODEV;
432 			break;
433 		}
434 		if (signal_pending(current)) {
435 			err = -ERESTARTSYS;
436 			break;
437 		}
438 	}
439 	remove_wait_queue(&rmidi->open_wait, &wait);
440 	if (err < 0) {
441 		kfree(rawmidi_file);
442 		goto __error;
443 	}
444 #ifdef CONFIG_SND_OSSEMUL
445 	if (rawmidi_file->input && rawmidi_file->input->runtime)
446 		rawmidi_file->input->runtime->oss = (maj == SOUND_MAJOR);
447 	if (rawmidi_file->output && rawmidi_file->output->runtime)
448 		rawmidi_file->output->runtime->oss = (maj == SOUND_MAJOR);
449 #endif
450 	file->private_data = rawmidi_file;
451 	mutex_unlock(&rmidi->open_mutex);
452 	snd_card_unref(rmidi->card);
453 	return 0;
454 
455  __error:
456 	snd_card_file_remove(card, file);
457  __error_card:
458 	mutex_unlock(&rmidi->open_mutex);
459 	module_put(rmidi->card->module);
460 	snd_card_unref(rmidi->card);
461 	return err;
462 }
463 
464 static void close_substream(struct snd_rawmidi *rmidi,
465 			    struct snd_rawmidi_substream *substream,
466 			    int cleanup)
467 {
468 	if (--substream->use_count)
469 		return;
470 
471 	if (cleanup) {
472 		if (substream->stream == SNDRV_RAWMIDI_STREAM_INPUT)
473 			snd_rawmidi_input_trigger(substream, 0);
474 		else {
475 			if (substream->active_sensing) {
476 				unsigned char buf = 0xfe;
477 				/* sending single active sensing message
478 				 * to shut the device up
479 				 */
480 				snd_rawmidi_kernel_write(substream, &buf, 1);
481 			}
482 			if (snd_rawmidi_drain_output(substream) == -ERESTARTSYS)
483 				snd_rawmidi_output_trigger(substream, 0);
484 		}
485 	}
486 	substream->ops->close(substream);
487 	if (substream->runtime->private_free)
488 		substream->runtime->private_free(substream);
489 	snd_rawmidi_runtime_free(substream);
490 	substream->opened = 0;
491 	substream->append = 0;
492 	put_pid(substream->pid);
493 	substream->pid = NULL;
494 	rmidi->streams[substream->stream].substream_opened--;
495 }
496 
497 static void rawmidi_release_priv(struct snd_rawmidi_file *rfile)
498 {
499 	struct snd_rawmidi *rmidi;
500 
501 	rmidi = rfile->rmidi;
502 	mutex_lock(&rmidi->open_mutex);
503 	if (rfile->input) {
504 		close_substream(rmidi, rfile->input, 1);
505 		rfile->input = NULL;
506 	}
507 	if (rfile->output) {
508 		close_substream(rmidi, rfile->output, 1);
509 		rfile->output = NULL;
510 	}
511 	rfile->rmidi = NULL;
512 	mutex_unlock(&rmidi->open_mutex);
513 	wake_up(&rmidi->open_wait);
514 }
515 
516 /* called from sound/core/seq/seq_midi.c */
517 int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile)
518 {
519 	struct snd_rawmidi *rmidi;
520 
521 	if (snd_BUG_ON(!rfile))
522 		return -ENXIO;
523 
524 	rmidi = rfile->rmidi;
525 	rawmidi_release_priv(rfile);
526 	module_put(rmidi->card->module);
527 	return 0;
528 }
529 EXPORT_SYMBOL(snd_rawmidi_kernel_release);
530 
531 static int snd_rawmidi_release(struct inode *inode, struct file *file)
532 {
533 	struct snd_rawmidi_file *rfile;
534 	struct snd_rawmidi *rmidi;
535 	struct module *module;
536 
537 	rfile = file->private_data;
538 	rmidi = rfile->rmidi;
539 	rawmidi_release_priv(rfile);
540 	kfree(rfile);
541 	module = rmidi->card->module;
542 	snd_card_file_remove(rmidi->card, file);
543 	module_put(module);
544 	return 0;
545 }
546 
547 static int snd_rawmidi_info(struct snd_rawmidi_substream *substream,
548 			    struct snd_rawmidi_info *info)
549 {
550 	struct snd_rawmidi *rmidi;
551 
552 	if (substream == NULL)
553 		return -ENODEV;
554 	rmidi = substream->rmidi;
555 	memset(info, 0, sizeof(*info));
556 	info->card = rmidi->card->number;
557 	info->device = rmidi->device;
558 	info->subdevice = substream->number;
559 	info->stream = substream->stream;
560 	info->flags = rmidi->info_flags;
561 	strcpy(info->id, rmidi->id);
562 	strcpy(info->name, rmidi->name);
563 	strcpy(info->subname, substream->name);
564 	info->subdevices_count = substream->pstr->substream_count;
565 	info->subdevices_avail = (substream->pstr->substream_count -
566 				  substream->pstr->substream_opened);
567 	return 0;
568 }
569 
570 static int snd_rawmidi_info_user(struct snd_rawmidi_substream *substream,
571 				 struct snd_rawmidi_info __user * _info)
572 {
573 	struct snd_rawmidi_info info;
574 	int err;
575 	if ((err = snd_rawmidi_info(substream, &info)) < 0)
576 		return err;
577 	if (copy_to_user(_info, &info, sizeof(struct snd_rawmidi_info)))
578 		return -EFAULT;
579 	return 0;
580 }
581 
582 int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info)
583 {
584 	struct snd_rawmidi *rmidi;
585 	struct snd_rawmidi_str *pstr;
586 	struct snd_rawmidi_substream *substream;
587 
588 	mutex_lock(&register_mutex);
589 	rmidi = snd_rawmidi_search(card, info->device);
590 	mutex_unlock(&register_mutex);
591 	if (!rmidi)
592 		return -ENXIO;
593 	if (info->stream < 0 || info->stream > 1)
594 		return -EINVAL;
595 	pstr = &rmidi->streams[info->stream];
596 	if (pstr->substream_count == 0)
597 		return -ENOENT;
598 	if (info->subdevice >= pstr->substream_count)
599 		return -ENXIO;
600 	list_for_each_entry(substream, &pstr->substreams, list) {
601 		if ((unsigned int)substream->number == info->subdevice)
602 			return snd_rawmidi_info(substream, info);
603 	}
604 	return -ENXIO;
605 }
606 EXPORT_SYMBOL(snd_rawmidi_info_select);
607 
608 static int snd_rawmidi_info_select_user(struct snd_card *card,
609 					struct snd_rawmidi_info __user *_info)
610 {
611 	int err;
612 	struct snd_rawmidi_info info;
613 	if (get_user(info.device, &_info->device))
614 		return -EFAULT;
615 	if (get_user(info.stream, &_info->stream))
616 		return -EFAULT;
617 	if (get_user(info.subdevice, &_info->subdevice))
618 		return -EFAULT;
619 	if ((err = snd_rawmidi_info_select(card, &info)) < 0)
620 		return err;
621 	if (copy_to_user(_info, &info, sizeof(struct snd_rawmidi_info)))
622 		return -EFAULT;
623 	return 0;
624 }
625 
626 int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
627 			      struct snd_rawmidi_params * params)
628 {
629 	char *newbuf;
630 	struct snd_rawmidi_runtime *runtime = substream->runtime;
631 
632 	if (substream->append && substream->use_count > 1)
633 		return -EBUSY;
634 	snd_rawmidi_drain_output(substream);
635 	if (params->buffer_size < 32 || params->buffer_size > 1024L * 1024L) {
636 		return -EINVAL;
637 	}
638 	if (params->avail_min < 1 || params->avail_min > params->buffer_size) {
639 		return -EINVAL;
640 	}
641 	if (params->buffer_size != runtime->buffer_size) {
642 		newbuf = krealloc(runtime->buffer, params->buffer_size,
643 				  GFP_KERNEL);
644 		if (!newbuf)
645 			return -ENOMEM;
646 		runtime->buffer = newbuf;
647 		runtime->buffer_size = params->buffer_size;
648 		runtime->avail = runtime->buffer_size;
649 	}
650 	runtime->avail_min = params->avail_min;
651 	substream->active_sensing = !params->no_active_sensing;
652 	return 0;
653 }
654 EXPORT_SYMBOL(snd_rawmidi_output_params);
655 
656 int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
657 			     struct snd_rawmidi_params * params)
658 {
659 	char *newbuf;
660 	struct snd_rawmidi_runtime *runtime = substream->runtime;
661 
662 	snd_rawmidi_drain_input(substream);
663 	if (params->buffer_size < 32 || params->buffer_size > 1024L * 1024L) {
664 		return -EINVAL;
665 	}
666 	if (params->avail_min < 1 || params->avail_min > params->buffer_size) {
667 		return -EINVAL;
668 	}
669 	if (params->buffer_size != runtime->buffer_size) {
670 		newbuf = krealloc(runtime->buffer, params->buffer_size,
671 				  GFP_KERNEL);
672 		if (!newbuf)
673 			return -ENOMEM;
674 		runtime->buffer = newbuf;
675 		runtime->buffer_size = params->buffer_size;
676 	}
677 	runtime->avail_min = params->avail_min;
678 	return 0;
679 }
680 EXPORT_SYMBOL(snd_rawmidi_input_params);
681 
682 static int snd_rawmidi_output_status(struct snd_rawmidi_substream *substream,
683 				     struct snd_rawmidi_status * status)
684 {
685 	struct snd_rawmidi_runtime *runtime = substream->runtime;
686 
687 	memset(status, 0, sizeof(*status));
688 	status->stream = SNDRV_RAWMIDI_STREAM_OUTPUT;
689 	spin_lock_irq(&runtime->lock);
690 	status->avail = runtime->avail;
691 	spin_unlock_irq(&runtime->lock);
692 	return 0;
693 }
694 
695 static int snd_rawmidi_input_status(struct snd_rawmidi_substream *substream,
696 				    struct snd_rawmidi_status * status)
697 {
698 	struct snd_rawmidi_runtime *runtime = substream->runtime;
699 
700 	memset(status, 0, sizeof(*status));
701 	status->stream = SNDRV_RAWMIDI_STREAM_INPUT;
702 	spin_lock_irq(&runtime->lock);
703 	status->avail = runtime->avail;
704 	status->xruns = runtime->xruns;
705 	runtime->xruns = 0;
706 	spin_unlock_irq(&runtime->lock);
707 	return 0;
708 }
709 
710 static long snd_rawmidi_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
711 {
712 	struct snd_rawmidi_file *rfile;
713 	void __user *argp = (void __user *)arg;
714 
715 	rfile = file->private_data;
716 	if (((cmd >> 8) & 0xff) != 'W')
717 		return -ENOTTY;
718 	switch (cmd) {
719 	case SNDRV_RAWMIDI_IOCTL_PVERSION:
720 		return put_user(SNDRV_RAWMIDI_VERSION, (int __user *)argp) ? -EFAULT : 0;
721 	case SNDRV_RAWMIDI_IOCTL_INFO:
722 	{
723 		int stream;
724 		struct snd_rawmidi_info __user *info = argp;
725 		if (get_user(stream, &info->stream))
726 			return -EFAULT;
727 		switch (stream) {
728 		case SNDRV_RAWMIDI_STREAM_INPUT:
729 			return snd_rawmidi_info_user(rfile->input, info);
730 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
731 			return snd_rawmidi_info_user(rfile->output, info);
732 		default:
733 			return -EINVAL;
734 		}
735 	}
736 	case SNDRV_RAWMIDI_IOCTL_PARAMS:
737 	{
738 		struct snd_rawmidi_params params;
739 		if (copy_from_user(&params, argp, sizeof(struct snd_rawmidi_params)))
740 			return -EFAULT;
741 		switch (params.stream) {
742 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
743 			if (rfile->output == NULL)
744 				return -EINVAL;
745 			return snd_rawmidi_output_params(rfile->output, &params);
746 		case SNDRV_RAWMIDI_STREAM_INPUT:
747 			if (rfile->input == NULL)
748 				return -EINVAL;
749 			return snd_rawmidi_input_params(rfile->input, &params);
750 		default:
751 			return -EINVAL;
752 		}
753 	}
754 	case SNDRV_RAWMIDI_IOCTL_STATUS:
755 	{
756 		int err = 0;
757 		struct snd_rawmidi_status status;
758 		if (copy_from_user(&status, argp, sizeof(struct snd_rawmidi_status)))
759 			return -EFAULT;
760 		switch (status.stream) {
761 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
762 			if (rfile->output == NULL)
763 				return -EINVAL;
764 			err = snd_rawmidi_output_status(rfile->output, &status);
765 			break;
766 		case SNDRV_RAWMIDI_STREAM_INPUT:
767 			if (rfile->input == NULL)
768 				return -EINVAL;
769 			err = snd_rawmidi_input_status(rfile->input, &status);
770 			break;
771 		default:
772 			return -EINVAL;
773 		}
774 		if (err < 0)
775 			return err;
776 		if (copy_to_user(argp, &status, sizeof(struct snd_rawmidi_status)))
777 			return -EFAULT;
778 		return 0;
779 	}
780 	case SNDRV_RAWMIDI_IOCTL_DROP:
781 	{
782 		int val;
783 		if (get_user(val, (int __user *) argp))
784 			return -EFAULT;
785 		switch (val) {
786 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
787 			if (rfile->output == NULL)
788 				return -EINVAL;
789 			return snd_rawmidi_drop_output(rfile->output);
790 		default:
791 			return -EINVAL;
792 		}
793 	}
794 	case SNDRV_RAWMIDI_IOCTL_DRAIN:
795 	{
796 		int val;
797 		if (get_user(val, (int __user *) argp))
798 			return -EFAULT;
799 		switch (val) {
800 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
801 			if (rfile->output == NULL)
802 				return -EINVAL;
803 			return snd_rawmidi_drain_output(rfile->output);
804 		case SNDRV_RAWMIDI_STREAM_INPUT:
805 			if (rfile->input == NULL)
806 				return -EINVAL;
807 			return snd_rawmidi_drain_input(rfile->input);
808 		default:
809 			return -EINVAL;
810 		}
811 	}
812 	default:
813 		rmidi_dbg(rfile->rmidi,
814 			  "rawmidi: unknown command = 0x%x\n", cmd);
815 	}
816 	return -ENOTTY;
817 }
818 
819 static int snd_rawmidi_control_ioctl(struct snd_card *card,
820 				     struct snd_ctl_file *control,
821 				     unsigned int cmd,
822 				     unsigned long arg)
823 {
824 	void __user *argp = (void __user *)arg;
825 
826 	switch (cmd) {
827 	case SNDRV_CTL_IOCTL_RAWMIDI_NEXT_DEVICE:
828 	{
829 		int device;
830 
831 		if (get_user(device, (int __user *)argp))
832 			return -EFAULT;
833 		if (device >= SNDRV_RAWMIDI_DEVICES) /* next device is -1 */
834 			device = SNDRV_RAWMIDI_DEVICES - 1;
835 		mutex_lock(&register_mutex);
836 		device = device < 0 ? 0 : device + 1;
837 		while (device < SNDRV_RAWMIDI_DEVICES) {
838 			if (snd_rawmidi_search(card, device))
839 				break;
840 			device++;
841 		}
842 		if (device == SNDRV_RAWMIDI_DEVICES)
843 			device = -1;
844 		mutex_unlock(&register_mutex);
845 		if (put_user(device, (int __user *)argp))
846 			return -EFAULT;
847 		return 0;
848 	}
849 	case SNDRV_CTL_IOCTL_RAWMIDI_PREFER_SUBDEVICE:
850 	{
851 		int val;
852 
853 		if (get_user(val, (int __user *)argp))
854 			return -EFAULT;
855 		control->preferred_subdevice[SND_CTL_SUBDEV_RAWMIDI] = val;
856 		return 0;
857 	}
858 	case SNDRV_CTL_IOCTL_RAWMIDI_INFO:
859 		return snd_rawmidi_info_select_user(card, argp);
860 	}
861 	return -ENOIOCTLCMD;
862 }
863 
864 /**
865  * snd_rawmidi_receive - receive the input data from the device
866  * @substream: the rawmidi substream
867  * @buffer: the buffer pointer
868  * @count: the data size to read
869  *
870  * Reads the data from the internal buffer.
871  *
872  * Return: The size of read data, or a negative error code on failure.
873  */
874 int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
875 			const unsigned char *buffer, int count)
876 {
877 	unsigned long flags;
878 	int result = 0, count1;
879 	struct snd_rawmidi_runtime *runtime = substream->runtime;
880 
881 	if (!substream->opened)
882 		return -EBADFD;
883 	if (runtime->buffer == NULL) {
884 		rmidi_dbg(substream->rmidi,
885 			  "snd_rawmidi_receive: input is not active!!!\n");
886 		return -EINVAL;
887 	}
888 	spin_lock_irqsave(&runtime->lock, flags);
889 	if (count == 1) {	/* special case, faster code */
890 		substream->bytes++;
891 		if (runtime->avail < runtime->buffer_size) {
892 			runtime->buffer[runtime->hw_ptr++] = buffer[0];
893 			runtime->hw_ptr %= runtime->buffer_size;
894 			runtime->avail++;
895 			result++;
896 		} else {
897 			runtime->xruns++;
898 		}
899 	} else {
900 		substream->bytes += count;
901 		count1 = runtime->buffer_size - runtime->hw_ptr;
902 		if (count1 > count)
903 			count1 = count;
904 		if (count1 > (int)(runtime->buffer_size - runtime->avail))
905 			count1 = runtime->buffer_size - runtime->avail;
906 		memcpy(runtime->buffer + runtime->hw_ptr, buffer, count1);
907 		runtime->hw_ptr += count1;
908 		runtime->hw_ptr %= runtime->buffer_size;
909 		runtime->avail += count1;
910 		count -= count1;
911 		result += count1;
912 		if (count > 0) {
913 			buffer += count1;
914 			count1 = count;
915 			if (count1 > (int)(runtime->buffer_size - runtime->avail)) {
916 				count1 = runtime->buffer_size - runtime->avail;
917 				runtime->xruns += count - count1;
918 			}
919 			if (count1 > 0) {
920 				memcpy(runtime->buffer, buffer, count1);
921 				runtime->hw_ptr = count1;
922 				runtime->avail += count1;
923 				result += count1;
924 			}
925 		}
926 	}
927 	if (result > 0) {
928 		if (runtime->event)
929 			schedule_work(&runtime->event_work);
930 		else if (snd_rawmidi_ready(substream))
931 			wake_up(&runtime->sleep);
932 	}
933 	spin_unlock_irqrestore(&runtime->lock, flags);
934 	return result;
935 }
936 EXPORT_SYMBOL(snd_rawmidi_receive);
937 
938 static long snd_rawmidi_kernel_read1(struct snd_rawmidi_substream *substream,
939 				     unsigned char __user *userbuf,
940 				     unsigned char *kernelbuf, long count)
941 {
942 	unsigned long flags;
943 	long result = 0, count1;
944 	struct snd_rawmidi_runtime *runtime = substream->runtime;
945 	unsigned long appl_ptr;
946 
947 	spin_lock_irqsave(&runtime->lock, flags);
948 	while (count > 0 && runtime->avail) {
949 		count1 = runtime->buffer_size - runtime->appl_ptr;
950 		if (count1 > count)
951 			count1 = count;
952 		if (count1 > (int)runtime->avail)
953 			count1 = runtime->avail;
954 
955 		/* update runtime->appl_ptr before unlocking for userbuf */
956 		appl_ptr = runtime->appl_ptr;
957 		runtime->appl_ptr += count1;
958 		runtime->appl_ptr %= runtime->buffer_size;
959 		runtime->avail -= count1;
960 
961 		if (kernelbuf)
962 			memcpy(kernelbuf + result, runtime->buffer + appl_ptr, count1);
963 		if (userbuf) {
964 			spin_unlock_irqrestore(&runtime->lock, flags);
965 			if (copy_to_user(userbuf + result,
966 					 runtime->buffer + appl_ptr, count1)) {
967 				return result > 0 ? result : -EFAULT;
968 			}
969 			spin_lock_irqsave(&runtime->lock, flags);
970 		}
971 		result += count1;
972 		count -= count1;
973 	}
974 	spin_unlock_irqrestore(&runtime->lock, flags);
975 	return result;
976 }
977 
978 long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
979 			     unsigned char *buf, long count)
980 {
981 	snd_rawmidi_input_trigger(substream, 1);
982 	return snd_rawmidi_kernel_read1(substream, NULL/*userbuf*/, buf, count);
983 }
984 EXPORT_SYMBOL(snd_rawmidi_kernel_read);
985 
986 static ssize_t snd_rawmidi_read(struct file *file, char __user *buf, size_t count,
987 				loff_t *offset)
988 {
989 	long result;
990 	int count1;
991 	struct snd_rawmidi_file *rfile;
992 	struct snd_rawmidi_substream *substream;
993 	struct snd_rawmidi_runtime *runtime;
994 
995 	rfile = file->private_data;
996 	substream = rfile->input;
997 	if (substream == NULL)
998 		return -EIO;
999 	runtime = substream->runtime;
1000 	snd_rawmidi_input_trigger(substream, 1);
1001 	result = 0;
1002 	while (count > 0) {
1003 		spin_lock_irq(&runtime->lock);
1004 		while (!snd_rawmidi_ready(substream)) {
1005 			wait_queue_entry_t wait;
1006 			if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1007 				spin_unlock_irq(&runtime->lock);
1008 				return result > 0 ? result : -EAGAIN;
1009 			}
1010 			init_waitqueue_entry(&wait, current);
1011 			add_wait_queue(&runtime->sleep, &wait);
1012 			set_current_state(TASK_INTERRUPTIBLE);
1013 			spin_unlock_irq(&runtime->lock);
1014 			schedule();
1015 			remove_wait_queue(&runtime->sleep, &wait);
1016 			if (rfile->rmidi->card->shutdown)
1017 				return -ENODEV;
1018 			if (signal_pending(current))
1019 				return result > 0 ? result : -ERESTARTSYS;
1020 			if (!runtime->avail)
1021 				return result > 0 ? result : -EIO;
1022 			spin_lock_irq(&runtime->lock);
1023 		}
1024 		spin_unlock_irq(&runtime->lock);
1025 		count1 = snd_rawmidi_kernel_read1(substream,
1026 						  (unsigned char __user *)buf,
1027 						  NULL/*kernelbuf*/,
1028 						  count);
1029 		if (count1 < 0)
1030 			return result > 0 ? result : count1;
1031 		result += count1;
1032 		buf += count1;
1033 		count -= count1;
1034 	}
1035 	return result;
1036 }
1037 
1038 /**
1039  * snd_rawmidi_transmit_empty - check whether the output buffer is empty
1040  * @substream: the rawmidi substream
1041  *
1042  * Return: 1 if the internal output buffer is empty, 0 if not.
1043  */
1044 int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream)
1045 {
1046 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1047 	int result;
1048 	unsigned long flags;
1049 
1050 	if (runtime->buffer == NULL) {
1051 		rmidi_dbg(substream->rmidi,
1052 			  "snd_rawmidi_transmit_empty: output is not active!!!\n");
1053 		return 1;
1054 	}
1055 	spin_lock_irqsave(&runtime->lock, flags);
1056 	result = runtime->avail >= runtime->buffer_size;
1057 	spin_unlock_irqrestore(&runtime->lock, flags);
1058 	return result;
1059 }
1060 EXPORT_SYMBOL(snd_rawmidi_transmit_empty);
1061 
1062 /**
1063  * __snd_rawmidi_transmit_peek - copy data from the internal buffer
1064  * @substream: the rawmidi substream
1065  * @buffer: the buffer pointer
1066  * @count: data size to transfer
1067  *
1068  * This is a variant of snd_rawmidi_transmit_peek() without spinlock.
1069  */
1070 int __snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
1071 			      unsigned char *buffer, int count)
1072 {
1073 	int result, count1;
1074 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1075 
1076 	if (runtime->buffer == NULL) {
1077 		rmidi_dbg(substream->rmidi,
1078 			  "snd_rawmidi_transmit_peek: output is not active!!!\n");
1079 		return -EINVAL;
1080 	}
1081 	result = 0;
1082 	if (runtime->avail >= runtime->buffer_size) {
1083 		/* warning: lowlevel layer MUST trigger down the hardware */
1084 		goto __skip;
1085 	}
1086 	if (count == 1) {	/* special case, faster code */
1087 		*buffer = runtime->buffer[runtime->hw_ptr];
1088 		result++;
1089 	} else {
1090 		count1 = runtime->buffer_size - runtime->hw_ptr;
1091 		if (count1 > count)
1092 			count1 = count;
1093 		if (count1 > (int)(runtime->buffer_size - runtime->avail))
1094 			count1 = runtime->buffer_size - runtime->avail;
1095 		memcpy(buffer, runtime->buffer + runtime->hw_ptr, count1);
1096 		count -= count1;
1097 		result += count1;
1098 		if (count > 0) {
1099 			if (count > (int)(runtime->buffer_size - runtime->avail - count1))
1100 				count = runtime->buffer_size - runtime->avail - count1;
1101 			memcpy(buffer + count1, runtime->buffer, count);
1102 			result += count;
1103 		}
1104 	}
1105       __skip:
1106 	return result;
1107 }
1108 EXPORT_SYMBOL(__snd_rawmidi_transmit_peek);
1109 
1110 /**
1111  * snd_rawmidi_transmit_peek - copy data from the internal buffer
1112  * @substream: the rawmidi substream
1113  * @buffer: the buffer pointer
1114  * @count: data size to transfer
1115  *
1116  * Copies data from the internal output buffer to the given buffer.
1117  *
1118  * Call this in the interrupt handler when the midi output is ready,
1119  * and call snd_rawmidi_transmit_ack() after the transmission is
1120  * finished.
1121  *
1122  * Return: The size of copied data, or a negative error code on failure.
1123  */
1124 int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
1125 			      unsigned char *buffer, int count)
1126 {
1127 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1128 	int result;
1129 	unsigned long flags;
1130 
1131 	spin_lock_irqsave(&runtime->lock, flags);
1132 	result = __snd_rawmidi_transmit_peek(substream, buffer, count);
1133 	spin_unlock_irqrestore(&runtime->lock, flags);
1134 	return result;
1135 }
1136 EXPORT_SYMBOL(snd_rawmidi_transmit_peek);
1137 
1138 /**
1139  * __snd_rawmidi_transmit_ack - acknowledge the transmission
1140  * @substream: the rawmidi substream
1141  * @count: the transferred count
1142  *
1143  * This is a variant of __snd_rawmidi_transmit_ack() without spinlock.
1144  */
1145 int __snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count)
1146 {
1147 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1148 
1149 	if (runtime->buffer == NULL) {
1150 		rmidi_dbg(substream->rmidi,
1151 			  "snd_rawmidi_transmit_ack: output is not active!!!\n");
1152 		return -EINVAL;
1153 	}
1154 	snd_BUG_ON(runtime->avail + count > runtime->buffer_size);
1155 	runtime->hw_ptr += count;
1156 	runtime->hw_ptr %= runtime->buffer_size;
1157 	runtime->avail += count;
1158 	substream->bytes += count;
1159 	if (count > 0) {
1160 		if (runtime->drain || snd_rawmidi_ready(substream))
1161 			wake_up(&runtime->sleep);
1162 	}
1163 	return count;
1164 }
1165 EXPORT_SYMBOL(__snd_rawmidi_transmit_ack);
1166 
1167 /**
1168  * snd_rawmidi_transmit_ack - acknowledge the transmission
1169  * @substream: the rawmidi substream
1170  * @count: the transferred count
1171  *
1172  * Advances the hardware pointer for the internal output buffer with
1173  * the given size and updates the condition.
1174  * Call after the transmission is finished.
1175  *
1176  * Return: The advanced size if successful, or a negative error code on failure.
1177  */
1178 int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count)
1179 {
1180 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1181 	int result;
1182 	unsigned long flags;
1183 
1184 	spin_lock_irqsave(&runtime->lock, flags);
1185 	result = __snd_rawmidi_transmit_ack(substream, count);
1186 	spin_unlock_irqrestore(&runtime->lock, flags);
1187 	return result;
1188 }
1189 EXPORT_SYMBOL(snd_rawmidi_transmit_ack);
1190 
1191 /**
1192  * snd_rawmidi_transmit - copy from the buffer to the device
1193  * @substream: the rawmidi substream
1194  * @buffer: the buffer pointer
1195  * @count: the data size to transfer
1196  *
1197  * Copies data from the buffer to the device and advances the pointer.
1198  *
1199  * Return: The copied size if successful, or a negative error code on failure.
1200  */
1201 int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
1202 			 unsigned char *buffer, int count)
1203 {
1204 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1205 	int result;
1206 	unsigned long flags;
1207 
1208 	spin_lock_irqsave(&runtime->lock, flags);
1209 	if (!substream->opened)
1210 		result = -EBADFD;
1211 	else {
1212 		count = __snd_rawmidi_transmit_peek(substream, buffer, count);
1213 		if (count <= 0)
1214 			result = count;
1215 		else
1216 			result = __snd_rawmidi_transmit_ack(substream, count);
1217 	}
1218 	spin_unlock_irqrestore(&runtime->lock, flags);
1219 	return result;
1220 }
1221 EXPORT_SYMBOL(snd_rawmidi_transmit);
1222 
1223 static long snd_rawmidi_kernel_write1(struct snd_rawmidi_substream *substream,
1224 				      const unsigned char __user *userbuf,
1225 				      const unsigned char *kernelbuf,
1226 				      long count)
1227 {
1228 	unsigned long flags;
1229 	long count1, result;
1230 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1231 	unsigned long appl_ptr;
1232 
1233 	if (!kernelbuf && !userbuf)
1234 		return -EINVAL;
1235 	if (snd_BUG_ON(!runtime->buffer))
1236 		return -EINVAL;
1237 
1238 	result = 0;
1239 	spin_lock_irqsave(&runtime->lock, flags);
1240 	if (substream->append) {
1241 		if ((long)runtime->avail < count) {
1242 			spin_unlock_irqrestore(&runtime->lock, flags);
1243 			return -EAGAIN;
1244 		}
1245 	}
1246 	while (count > 0 && runtime->avail > 0) {
1247 		count1 = runtime->buffer_size - runtime->appl_ptr;
1248 		if (count1 > count)
1249 			count1 = count;
1250 		if (count1 > (long)runtime->avail)
1251 			count1 = runtime->avail;
1252 
1253 		/* update runtime->appl_ptr before unlocking for userbuf */
1254 		appl_ptr = runtime->appl_ptr;
1255 		runtime->appl_ptr += count1;
1256 		runtime->appl_ptr %= runtime->buffer_size;
1257 		runtime->avail -= count1;
1258 
1259 		if (kernelbuf)
1260 			memcpy(runtime->buffer + appl_ptr,
1261 			       kernelbuf + result, count1);
1262 		else if (userbuf) {
1263 			spin_unlock_irqrestore(&runtime->lock, flags);
1264 			if (copy_from_user(runtime->buffer + appl_ptr,
1265 					   userbuf + result, count1)) {
1266 				spin_lock_irqsave(&runtime->lock, flags);
1267 				result = result > 0 ? result : -EFAULT;
1268 				goto __end;
1269 			}
1270 			spin_lock_irqsave(&runtime->lock, flags);
1271 		}
1272 		result += count1;
1273 		count -= count1;
1274 	}
1275       __end:
1276 	count1 = runtime->avail < runtime->buffer_size;
1277 	spin_unlock_irqrestore(&runtime->lock, flags);
1278 	if (count1)
1279 		snd_rawmidi_output_trigger(substream, 1);
1280 	return result;
1281 }
1282 
1283 long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
1284 			      const unsigned char *buf, long count)
1285 {
1286 	return snd_rawmidi_kernel_write1(substream, NULL, buf, count);
1287 }
1288 EXPORT_SYMBOL(snd_rawmidi_kernel_write);
1289 
1290 static ssize_t snd_rawmidi_write(struct file *file, const char __user *buf,
1291 				 size_t count, loff_t *offset)
1292 {
1293 	long result, timeout;
1294 	int count1;
1295 	struct snd_rawmidi_file *rfile;
1296 	struct snd_rawmidi_runtime *runtime;
1297 	struct snd_rawmidi_substream *substream;
1298 
1299 	rfile = file->private_data;
1300 	substream = rfile->output;
1301 	runtime = substream->runtime;
1302 	/* we cannot put an atomic message to our buffer */
1303 	if (substream->append && count > runtime->buffer_size)
1304 		return -EIO;
1305 	result = 0;
1306 	while (count > 0) {
1307 		spin_lock_irq(&runtime->lock);
1308 		while (!snd_rawmidi_ready_append(substream, count)) {
1309 			wait_queue_entry_t wait;
1310 			if (file->f_flags & O_NONBLOCK) {
1311 				spin_unlock_irq(&runtime->lock);
1312 				return result > 0 ? result : -EAGAIN;
1313 			}
1314 			init_waitqueue_entry(&wait, current);
1315 			add_wait_queue(&runtime->sleep, &wait);
1316 			set_current_state(TASK_INTERRUPTIBLE);
1317 			spin_unlock_irq(&runtime->lock);
1318 			timeout = schedule_timeout(30 * HZ);
1319 			remove_wait_queue(&runtime->sleep, &wait);
1320 			if (rfile->rmidi->card->shutdown)
1321 				return -ENODEV;
1322 			if (signal_pending(current))
1323 				return result > 0 ? result : -ERESTARTSYS;
1324 			if (!runtime->avail && !timeout)
1325 				return result > 0 ? result : -EIO;
1326 			spin_lock_irq(&runtime->lock);
1327 		}
1328 		spin_unlock_irq(&runtime->lock);
1329 		count1 = snd_rawmidi_kernel_write1(substream, buf, NULL, count);
1330 		if (count1 < 0)
1331 			return result > 0 ? result : count1;
1332 		result += count1;
1333 		buf += count1;
1334 		if ((size_t)count1 < count && (file->f_flags & O_NONBLOCK))
1335 			break;
1336 		count -= count1;
1337 	}
1338 	if (file->f_flags & O_DSYNC) {
1339 		spin_lock_irq(&runtime->lock);
1340 		while (runtime->avail != runtime->buffer_size) {
1341 			wait_queue_entry_t wait;
1342 			unsigned int last_avail = runtime->avail;
1343 			init_waitqueue_entry(&wait, current);
1344 			add_wait_queue(&runtime->sleep, &wait);
1345 			set_current_state(TASK_INTERRUPTIBLE);
1346 			spin_unlock_irq(&runtime->lock);
1347 			timeout = schedule_timeout(30 * HZ);
1348 			remove_wait_queue(&runtime->sleep, &wait);
1349 			if (signal_pending(current))
1350 				return result > 0 ? result : -ERESTARTSYS;
1351 			if (runtime->avail == last_avail && !timeout)
1352 				return result > 0 ? result : -EIO;
1353 			spin_lock_irq(&runtime->lock);
1354 		}
1355 		spin_unlock_irq(&runtime->lock);
1356 	}
1357 	return result;
1358 }
1359 
1360 static unsigned int snd_rawmidi_poll(struct file *file, poll_table * wait)
1361 {
1362 	struct snd_rawmidi_file *rfile;
1363 	struct snd_rawmidi_runtime *runtime;
1364 	unsigned int mask;
1365 
1366 	rfile = file->private_data;
1367 	if (rfile->input != NULL) {
1368 		runtime = rfile->input->runtime;
1369 		snd_rawmidi_input_trigger(rfile->input, 1);
1370 		poll_wait(file, &runtime->sleep, wait);
1371 	}
1372 	if (rfile->output != NULL) {
1373 		runtime = rfile->output->runtime;
1374 		poll_wait(file, &runtime->sleep, wait);
1375 	}
1376 	mask = 0;
1377 	if (rfile->input != NULL) {
1378 		if (snd_rawmidi_ready(rfile->input))
1379 			mask |= POLLIN | POLLRDNORM;
1380 	}
1381 	if (rfile->output != NULL) {
1382 		if (snd_rawmidi_ready(rfile->output))
1383 			mask |= POLLOUT | POLLWRNORM;
1384 	}
1385 	return mask;
1386 }
1387 
1388 /*
1389  */
1390 #ifdef CONFIG_COMPAT
1391 #include "rawmidi_compat.c"
1392 #else
1393 #define snd_rawmidi_ioctl_compat	NULL
1394 #endif
1395 
1396 /*
1397 
1398  */
1399 
1400 static void snd_rawmidi_proc_info_read(struct snd_info_entry *entry,
1401 				       struct snd_info_buffer *buffer)
1402 {
1403 	struct snd_rawmidi *rmidi;
1404 	struct snd_rawmidi_substream *substream;
1405 	struct snd_rawmidi_runtime *runtime;
1406 
1407 	rmidi = entry->private_data;
1408 	snd_iprintf(buffer, "%s\n\n", rmidi->name);
1409 	mutex_lock(&rmidi->open_mutex);
1410 	if (rmidi->info_flags & SNDRV_RAWMIDI_INFO_OUTPUT) {
1411 		list_for_each_entry(substream,
1412 				    &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams,
1413 				    list) {
1414 			snd_iprintf(buffer,
1415 				    "Output %d\n"
1416 				    "  Tx bytes     : %lu\n",
1417 				    substream->number,
1418 				    (unsigned long) substream->bytes);
1419 			if (substream->opened) {
1420 				snd_iprintf(buffer,
1421 				    "  Owner PID    : %d\n",
1422 				    pid_vnr(substream->pid));
1423 				runtime = substream->runtime;
1424 				snd_iprintf(buffer,
1425 				    "  Mode         : %s\n"
1426 				    "  Buffer size  : %lu\n"
1427 				    "  Avail        : %lu\n",
1428 				    runtime->oss ? "OSS compatible" : "native",
1429 				    (unsigned long) runtime->buffer_size,
1430 				    (unsigned long) runtime->avail);
1431 			}
1432 		}
1433 	}
1434 	if (rmidi->info_flags & SNDRV_RAWMIDI_INFO_INPUT) {
1435 		list_for_each_entry(substream,
1436 				    &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams,
1437 				    list) {
1438 			snd_iprintf(buffer,
1439 				    "Input %d\n"
1440 				    "  Rx bytes     : %lu\n",
1441 				    substream->number,
1442 				    (unsigned long) substream->bytes);
1443 			if (substream->opened) {
1444 				snd_iprintf(buffer,
1445 					    "  Owner PID    : %d\n",
1446 					    pid_vnr(substream->pid));
1447 				runtime = substream->runtime;
1448 				snd_iprintf(buffer,
1449 					    "  Buffer size  : %lu\n"
1450 					    "  Avail        : %lu\n"
1451 					    "  Overruns     : %lu\n",
1452 					    (unsigned long) runtime->buffer_size,
1453 					    (unsigned long) runtime->avail,
1454 					    (unsigned long) runtime->xruns);
1455 			}
1456 		}
1457 	}
1458 	mutex_unlock(&rmidi->open_mutex);
1459 }
1460 
1461 /*
1462  *  Register functions
1463  */
1464 
1465 static const struct file_operations snd_rawmidi_f_ops =
1466 {
1467 	.owner =	THIS_MODULE,
1468 	.read =		snd_rawmidi_read,
1469 	.write =	snd_rawmidi_write,
1470 	.open =		snd_rawmidi_open,
1471 	.release =	snd_rawmidi_release,
1472 	.llseek =	no_llseek,
1473 	.poll =		snd_rawmidi_poll,
1474 	.unlocked_ioctl =	snd_rawmidi_ioctl,
1475 	.compat_ioctl =	snd_rawmidi_ioctl_compat,
1476 };
1477 
1478 static int snd_rawmidi_alloc_substreams(struct snd_rawmidi *rmidi,
1479 					struct snd_rawmidi_str *stream,
1480 					int direction,
1481 					int count)
1482 {
1483 	struct snd_rawmidi_substream *substream;
1484 	int idx;
1485 
1486 	for (idx = 0; idx < count; idx++) {
1487 		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
1488 		if (!substream)
1489 			return -ENOMEM;
1490 		substream->stream = direction;
1491 		substream->number = idx;
1492 		substream->rmidi = rmidi;
1493 		substream->pstr = stream;
1494 		list_add_tail(&substream->list, &stream->substreams);
1495 		stream->substream_count++;
1496 	}
1497 	return 0;
1498 }
1499 
1500 static void release_rawmidi_device(struct device *dev)
1501 {
1502 	kfree(container_of(dev, struct snd_rawmidi, dev));
1503 }
1504 
1505 /**
1506  * snd_rawmidi_new - create a rawmidi instance
1507  * @card: the card instance
1508  * @id: the id string
1509  * @device: the device index
1510  * @output_count: the number of output streams
1511  * @input_count: the number of input streams
1512  * @rrawmidi: the pointer to store the new rawmidi instance
1513  *
1514  * Creates a new rawmidi instance.
1515  * Use snd_rawmidi_set_ops() to set the operators to the new instance.
1516  *
1517  * Return: Zero if successful, or a negative error code on failure.
1518  */
1519 int snd_rawmidi_new(struct snd_card *card, char *id, int device,
1520 		    int output_count, int input_count,
1521 		    struct snd_rawmidi ** rrawmidi)
1522 {
1523 	struct snd_rawmidi *rmidi;
1524 	int err;
1525 	static struct snd_device_ops ops = {
1526 		.dev_free = snd_rawmidi_dev_free,
1527 		.dev_register = snd_rawmidi_dev_register,
1528 		.dev_disconnect = snd_rawmidi_dev_disconnect,
1529 	};
1530 
1531 	if (snd_BUG_ON(!card))
1532 		return -ENXIO;
1533 	if (rrawmidi)
1534 		*rrawmidi = NULL;
1535 	rmidi = kzalloc(sizeof(*rmidi), GFP_KERNEL);
1536 	if (!rmidi)
1537 		return -ENOMEM;
1538 	rmidi->card = card;
1539 	rmidi->device = device;
1540 	mutex_init(&rmidi->open_mutex);
1541 	init_waitqueue_head(&rmidi->open_wait);
1542 	INIT_LIST_HEAD(&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams);
1543 	INIT_LIST_HEAD(&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams);
1544 
1545 	if (id != NULL)
1546 		strlcpy(rmidi->id, id, sizeof(rmidi->id));
1547 
1548 	snd_device_initialize(&rmidi->dev, card);
1549 	rmidi->dev.release = release_rawmidi_device;
1550 	dev_set_name(&rmidi->dev, "midiC%iD%i", card->number, device);
1551 
1552 	if ((err = snd_rawmidi_alloc_substreams(rmidi,
1553 						&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT],
1554 						SNDRV_RAWMIDI_STREAM_INPUT,
1555 						input_count)) < 0) {
1556 		snd_rawmidi_free(rmidi);
1557 		return err;
1558 	}
1559 	if ((err = snd_rawmidi_alloc_substreams(rmidi,
1560 						&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT],
1561 						SNDRV_RAWMIDI_STREAM_OUTPUT,
1562 						output_count)) < 0) {
1563 		snd_rawmidi_free(rmidi);
1564 		return err;
1565 	}
1566 	if ((err = snd_device_new(card, SNDRV_DEV_RAWMIDI, rmidi, &ops)) < 0) {
1567 		snd_rawmidi_free(rmidi);
1568 		return err;
1569 	}
1570 	if (rrawmidi)
1571 		*rrawmidi = rmidi;
1572 	return 0;
1573 }
1574 EXPORT_SYMBOL(snd_rawmidi_new);
1575 
1576 static void snd_rawmidi_free_substreams(struct snd_rawmidi_str *stream)
1577 {
1578 	struct snd_rawmidi_substream *substream;
1579 
1580 	while (!list_empty(&stream->substreams)) {
1581 		substream = list_entry(stream->substreams.next, struct snd_rawmidi_substream, list);
1582 		list_del(&substream->list);
1583 		kfree(substream);
1584 	}
1585 }
1586 
1587 static int snd_rawmidi_free(struct snd_rawmidi *rmidi)
1588 {
1589 	if (!rmidi)
1590 		return 0;
1591 
1592 	snd_info_free_entry(rmidi->proc_entry);
1593 	rmidi->proc_entry = NULL;
1594 	mutex_lock(&register_mutex);
1595 	if (rmidi->ops && rmidi->ops->dev_unregister)
1596 		rmidi->ops->dev_unregister(rmidi);
1597 	mutex_unlock(&register_mutex);
1598 
1599 	snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
1600 	snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
1601 	if (rmidi->private_free)
1602 		rmidi->private_free(rmidi);
1603 	put_device(&rmidi->dev);
1604 	return 0;
1605 }
1606 
1607 static int snd_rawmidi_dev_free(struct snd_device *device)
1608 {
1609 	struct snd_rawmidi *rmidi = device->device_data;
1610 	return snd_rawmidi_free(rmidi);
1611 }
1612 
1613 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
1614 static void snd_rawmidi_dev_seq_free(struct snd_seq_device *device)
1615 {
1616 	struct snd_rawmidi *rmidi = device->private_data;
1617 	rmidi->seq_dev = NULL;
1618 }
1619 #endif
1620 
1621 static int snd_rawmidi_dev_register(struct snd_device *device)
1622 {
1623 	int err;
1624 	struct snd_info_entry *entry;
1625 	char name[16];
1626 	struct snd_rawmidi *rmidi = device->device_data;
1627 
1628 	if (rmidi->device >= SNDRV_RAWMIDI_DEVICES)
1629 		return -ENOMEM;
1630 	mutex_lock(&register_mutex);
1631 	if (snd_rawmidi_search(rmidi->card, rmidi->device)) {
1632 		mutex_unlock(&register_mutex);
1633 		return -EBUSY;
1634 	}
1635 	list_add_tail(&rmidi->list, &snd_rawmidi_devices);
1636 	mutex_unlock(&register_mutex);
1637 	err = snd_register_device(SNDRV_DEVICE_TYPE_RAWMIDI,
1638 				  rmidi->card, rmidi->device,
1639 				  &snd_rawmidi_f_ops, rmidi, &rmidi->dev);
1640 	if (err < 0) {
1641 		rmidi_err(rmidi, "unable to register\n");
1642 		mutex_lock(&register_mutex);
1643 		list_del(&rmidi->list);
1644 		mutex_unlock(&register_mutex);
1645 		return err;
1646 	}
1647 	if (rmidi->ops && rmidi->ops->dev_register &&
1648 	    (err = rmidi->ops->dev_register(rmidi)) < 0) {
1649 		snd_unregister_device(&rmidi->dev);
1650 		mutex_lock(&register_mutex);
1651 		list_del(&rmidi->list);
1652 		mutex_unlock(&register_mutex);
1653 		return err;
1654 	}
1655 #ifdef CONFIG_SND_OSSEMUL
1656 	rmidi->ossreg = 0;
1657 	if ((int)rmidi->device == midi_map[rmidi->card->number]) {
1658 		if (snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI,
1659 					    rmidi->card, 0, &snd_rawmidi_f_ops,
1660 					    rmidi) < 0) {
1661 			rmidi_err(rmidi,
1662 				  "unable to register OSS rawmidi device %i:%i\n",
1663 				  rmidi->card->number, 0);
1664 		} else {
1665 			rmidi->ossreg++;
1666 #ifdef SNDRV_OSS_INFO_DEV_MIDI
1667 			snd_oss_info_register(SNDRV_OSS_INFO_DEV_MIDI, rmidi->card->number, rmidi->name);
1668 #endif
1669 		}
1670 	}
1671 	if ((int)rmidi->device == amidi_map[rmidi->card->number]) {
1672 		if (snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI,
1673 					    rmidi->card, 1, &snd_rawmidi_f_ops,
1674 					    rmidi) < 0) {
1675 			rmidi_err(rmidi,
1676 				  "unable to register OSS rawmidi device %i:%i\n",
1677 				  rmidi->card->number, 1);
1678 		} else {
1679 			rmidi->ossreg++;
1680 		}
1681 	}
1682 #endif /* CONFIG_SND_OSSEMUL */
1683 	sprintf(name, "midi%d", rmidi->device);
1684 	entry = snd_info_create_card_entry(rmidi->card, name, rmidi->card->proc_root);
1685 	if (entry) {
1686 		entry->private_data = rmidi;
1687 		entry->c.text.read = snd_rawmidi_proc_info_read;
1688 		if (snd_info_register(entry) < 0) {
1689 			snd_info_free_entry(entry);
1690 			entry = NULL;
1691 		}
1692 	}
1693 	rmidi->proc_entry = entry;
1694 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
1695 	if (!rmidi->ops || !rmidi->ops->dev_register) { /* own registration mechanism */
1696 		if (snd_seq_device_new(rmidi->card, rmidi->device, SNDRV_SEQ_DEV_ID_MIDISYNTH, 0, &rmidi->seq_dev) >= 0) {
1697 			rmidi->seq_dev->private_data = rmidi;
1698 			rmidi->seq_dev->private_free = snd_rawmidi_dev_seq_free;
1699 			sprintf(rmidi->seq_dev->name, "MIDI %d-%d", rmidi->card->number, rmidi->device);
1700 			snd_device_register(rmidi->card, rmidi->seq_dev);
1701 		}
1702 	}
1703 #endif
1704 	return 0;
1705 }
1706 
1707 static int snd_rawmidi_dev_disconnect(struct snd_device *device)
1708 {
1709 	struct snd_rawmidi *rmidi = device->device_data;
1710 	int dir;
1711 
1712 	mutex_lock(&register_mutex);
1713 	mutex_lock(&rmidi->open_mutex);
1714 	wake_up(&rmidi->open_wait);
1715 	list_del_init(&rmidi->list);
1716 	for (dir = 0; dir < 2; dir++) {
1717 		struct snd_rawmidi_substream *s;
1718 		list_for_each_entry(s, &rmidi->streams[dir].substreams, list) {
1719 			if (s->runtime)
1720 				wake_up(&s->runtime->sleep);
1721 		}
1722 	}
1723 
1724 #ifdef CONFIG_SND_OSSEMUL
1725 	if (rmidi->ossreg) {
1726 		if ((int)rmidi->device == midi_map[rmidi->card->number]) {
1727 			snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI, rmidi->card, 0);
1728 #ifdef SNDRV_OSS_INFO_DEV_MIDI
1729 			snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_MIDI, rmidi->card->number);
1730 #endif
1731 		}
1732 		if ((int)rmidi->device == amidi_map[rmidi->card->number])
1733 			snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI, rmidi->card, 1);
1734 		rmidi->ossreg = 0;
1735 	}
1736 #endif /* CONFIG_SND_OSSEMUL */
1737 	snd_unregister_device(&rmidi->dev);
1738 	mutex_unlock(&rmidi->open_mutex);
1739 	mutex_unlock(&register_mutex);
1740 	return 0;
1741 }
1742 
1743 /**
1744  * snd_rawmidi_set_ops - set the rawmidi operators
1745  * @rmidi: the rawmidi instance
1746  * @stream: the stream direction, SNDRV_RAWMIDI_STREAM_XXX
1747  * @ops: the operator table
1748  *
1749  * Sets the rawmidi operators for the given stream direction.
1750  */
1751 void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream,
1752 			 const struct snd_rawmidi_ops *ops)
1753 {
1754 	struct snd_rawmidi_substream *substream;
1755 
1756 	list_for_each_entry(substream, &rmidi->streams[stream].substreams, list)
1757 		substream->ops = ops;
1758 }
1759 EXPORT_SYMBOL(snd_rawmidi_set_ops);
1760 
1761 /*
1762  *  ENTRY functions
1763  */
1764 
1765 static int __init alsa_rawmidi_init(void)
1766 {
1767 
1768 	snd_ctl_register_ioctl(snd_rawmidi_control_ioctl);
1769 	snd_ctl_register_ioctl_compat(snd_rawmidi_control_ioctl);
1770 #ifdef CONFIG_SND_OSSEMUL
1771 	{ int i;
1772 	/* check device map table */
1773 	for (i = 0; i < SNDRV_CARDS; i++) {
1774 		if (midi_map[i] < 0 || midi_map[i] >= SNDRV_RAWMIDI_DEVICES) {
1775 			pr_err("ALSA: rawmidi: invalid midi_map[%d] = %d\n",
1776 			       i, midi_map[i]);
1777 			midi_map[i] = 0;
1778 		}
1779 		if (amidi_map[i] < 0 || amidi_map[i] >= SNDRV_RAWMIDI_DEVICES) {
1780 			pr_err("ALSA: rawmidi: invalid amidi_map[%d] = %d\n",
1781 			       i, amidi_map[i]);
1782 			amidi_map[i] = 1;
1783 		}
1784 	}
1785 	}
1786 #endif /* CONFIG_SND_OSSEMUL */
1787 	return 0;
1788 }
1789 
1790 static void __exit alsa_rawmidi_exit(void)
1791 {
1792 	snd_ctl_unregister_ioctl(snd_rawmidi_control_ioctl);
1793 	snd_ctl_unregister_ioctl_compat(snd_rawmidi_control_ioctl);
1794 }
1795 
1796 module_init(alsa_rawmidi_init)
1797 module_exit(alsa_rawmidi_exit)
1798