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Merge tag 'nolibc.2023.04.04a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulm...
[linux-block.git] / sound / drivers / aloop.c
CommitLineData
1a59d1b8 1// SPDX-License-Identifier: GPL-2.0-or-later
597603d6
JK		 2/*
3 * Loopback soundcard
4 *
5 * Original code:
6 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
7 *
8 * More accurate positioning and full-duplex support:
9 * Copyright (c) Ahmet İnan <ainan at mathematik.uni-freiburg.de>
10 *
11 * Major (almost complete) rewrite:
12 * Copyright (c) by Takashi Iwai <tiwai@suse.de>
13 *
14 * A next major update in 2010 (separate timers for playback and capture):
15 * Copyright (c) Jaroslav Kysela <perex@perex.cz>
597603d6
JK		 16 */
17
18#include <linux/init.h>
19#include <linux/jiffies.h>
20#include <linux/slab.h>
21#include <linux/time.h>
22#include <linux/wait.h>
65a77217 23#include <linux/module.h>
597603d6
JK		 24#include <linux/platform_device.h>
25#include <sound/core.h>
26#include <sound/control.h>
27#include <sound/pcm.h>
b088b53e 28#include <sound/pcm_params.h>
e74670b6 29#include <sound/info.h>
597603d6 30#include <sound/initval.h>
26c53379 31#include <sound/timer.h>
597603d6
JK		 32
33MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
34MODULE_DESCRIPTION("A loopback soundcard");
35MODULE_LICENSE("GPL");
597603d6
JK		 36
37#define MAX_PCM_SUBSTREAMS 8
38
39static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; /* Index 0-MAX */
40static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; /* ID for this card */
a67ff6a5 41static bool enable[SNDRV_CARDS] = {1, [1 ... (SNDRV_CARDS - 1)] = 0};
597603d6
JK		 42static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
43static int pcm_notify[SNDRV_CARDS];
26c53379 44static char *timer_source[SNDRV_CARDS];
597603d6
JK		 45
46module_param_array(index, int, NULL, 0444);
47MODULE_PARM_DESC(index, "Index value for loopback soundcard.");
48module_param_array(id, charp, NULL, 0444);
49MODULE_PARM_DESC(id, "ID string for loopback soundcard.");
50module_param_array(enable, bool, NULL, 0444);
51MODULE_PARM_DESC(enable, "Enable this loopback soundcard.");
52module_param_array(pcm_substreams, int, NULL, 0444);
53MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-8) for loopback driver.");
54module_param_array(pcm_notify, int, NULL, 0444);
55MODULE_PARM_DESC(pcm_notify, "Break capture when PCM format/rate/channels changes.");
26c53379
TW		 56module_param_array(timer_source, charp, NULL, 0444);
57MODULE_PARM_DESC(timer_source, "Sound card name or number and device/subdevice number of timer to be used. Empty string for jiffies timer [default].");
597603d6
JK		 58
59#define NO_PITCH 100000
60
fd1f7c74
TW		 61#define CABLE_VALID_PLAYBACK BIT(SNDRV_PCM_STREAM_PLAYBACK)
62#define CABLE_VALID_CAPTURE BIT(SNDRV_PCM_STREAM_CAPTURE)
63#define CABLE_VALID_BOTH (CABLE_VALID_PLAYBACK | CABLE_VALID_CAPTURE)
64
133f3759 65struct loopback_cable;
597603d6
JK		 66struct loopback_pcm;
67
133f3759
TW		 68struct loopback_ops {
69 /* optional
70 * call in loopback->cable_lock
71 */
72 int (*open)(struct loopback_pcm *dpcm);
73 /* required
74 * call in cable->lock
75 */
76 int (*start)(struct loopback_pcm *dpcm);
77 /* required
78 * call in cable->lock
79 */
80 int (*stop)(struct loopback_pcm *dpcm);
81 /* optional */
82 int (*stop_sync)(struct loopback_pcm *dpcm);
83 /* optional */
84 int (*close_substream)(struct loopback_pcm *dpcm);
85 /* optional
86 * call in loopback->cable_lock
87 */
88 int (*close_cable)(struct loopback_pcm *dpcm);
89 /* optional
90 * call in cable->lock
91 */
92 unsigned int (*pos_update)(struct loopback_cable *cable);
93 /* optional */
94 void (*dpcm_info)(struct loopback_pcm *dpcm,
95 struct snd_info_buffer *buffer);
96};
97
597603d6
JK		 98struct loopback_cable {
99 spinlock_t lock;
100 struct loopback_pcm *streams[2];
101 struct snd_pcm_hardware hw;
102 /* flags */
103 unsigned int valid;
104 unsigned int running;
5de9e45f 105 unsigned int pause;
133f3759 106 /* timer specific */
e714fa93 107 const struct loopback_ops *ops;
26c53379
TW		 108 /* If sound timer is used */
109 struct {
110 int stream;
111 struct snd_timer_id id;
6053a712 112 struct work_struct event_work;
26c53379
TW		 113 struct snd_timer_instance *instance;
114 } snd_timer;
597603d6
JK		 115};
116
117struct loopback_setup {
118 unsigned int notify: 1;
119 unsigned int rate_shift;
8c356c52 120 snd_pcm_format_t format;
597603d6
JK		 121 unsigned int rate;
122 unsigned int channels;
123 struct snd_ctl_elem_id active_id;
124 struct snd_ctl_elem_id format_id;
125 struct snd_ctl_elem_id rate_id;
126 struct snd_ctl_elem_id channels_id;
127};
128
129struct loopback {
130 struct snd_card *card;
131 struct mutex cable_lock;
132 struct loopback_cable *cables[MAX_PCM_SUBSTREAMS][2];
133 struct snd_pcm *pcm[2];
134 struct loopback_setup setup[MAX_PCM_SUBSTREAMS][2];
26c53379 135 const char *timer_source;
597603d6
JK		 136};
137
138struct loopback_pcm {
139 struct loopback *loopback;
140 struct snd_pcm_substream *substream;
141 struct loopback_cable *cable;
142 unsigned int pcm_buffer_size;
143 unsigned int buf_pos; /* position in buffer */
144 unsigned int silent_size;
145 /* PCM parameters */
146 unsigned int pcm_period_size;
147 unsigned int pcm_bps; /* bytes per second */
148 unsigned int pcm_salign; /* bytes per sample * channels */
149 unsigned int pcm_rate_shift; /* rate shift value */
150 /* flags */
151 unsigned int period_update_pending :1;
152 /* timer stuff */
97dda3da
TW		 153 unsigned int irq_pos; /* fractional IRQ position in jiffies
154 * ticks
155 */
156 unsigned int period_size_frac; /* period size in jiffies ticks */
b012513c 157 unsigned int last_drift;
597603d6 158 unsigned long last_jiffies;
26c53379 159 /* If jiffies timer is used */
597603d6
JK		 160 struct timer_list timer;
161};
162
163static struct platform_device *devices[SNDRV_CARDS];
164
165static inline unsigned int byte_pos(struct loopback_pcm *dpcm, unsigned int x)
166{
167 if (dpcm->pcm_rate_shift == NO_PITCH) {
168 x /= HZ;
169 } else {
170 x = div_u64(NO_PITCH * (unsigned long long)x,
171 HZ * (unsigned long long)dpcm->pcm_rate_shift);
172 }
173 return x - (x % dpcm->pcm_salign);
174}
175
176static inline unsigned int frac_pos(struct loopback_pcm *dpcm, unsigned int x)
177{
178 if (dpcm->pcm_rate_shift == NO_PITCH) { /* no pitch */
179 return x * HZ;
180 } else {
181 x = div_u64(dpcm->pcm_rate_shift * (unsigned long long)x * HZ,
182 NO_PITCH);
183 }
184 return x;
185}
186
187static inline struct loopback_setup *get_setup(struct loopback_pcm *dpcm)
188{
189 int device = dpcm->substream->pstr->pcm->device;
190
191 if (dpcm->substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
192 device ^= 1;
193 return &dpcm->loopback->setup[dpcm->substream->number][device];
194}
195
196static inline unsigned int get_notify(struct loopback_pcm *dpcm)
197{
198 return get_setup(dpcm)->notify;
199}
200
201static inline unsigned int get_rate_shift(struct loopback_pcm *dpcm)
202{
203 return get_setup(dpcm)->rate_shift;
204}
205
999fc9f6 206/* call in cable->lock */
8e3bf7cd 207static int loopback_jiffies_timer_start(struct loopback_pcm *dpcm)
597603d6
JK		 208{
209 unsigned long tick;
210 unsigned int rate_shift = get_rate_shift(dpcm);
211
212 if (rate_shift != dpcm->pcm_rate_shift) {
213 dpcm->pcm_rate_shift = rate_shift;
214 dpcm->period_size_frac = frac_pos(dpcm, dpcm->pcm_period_size);
215 }
0db71023
JK		 216 if (dpcm->period_size_frac <= dpcm->irq_pos) {
217 dpcm->irq_pos %= dpcm->period_size_frac;
218 dpcm->period_update_pending = 1;
219 }
597603d6 220 tick = dpcm->period_size_frac - dpcm->irq_pos;
7ef74bdc 221 tick = DIV_ROUND_UP(tick, dpcm->pcm_bps);
db974553 222 mod_timer(&dpcm->timer, jiffies + tick);
09419f1a
TW		 223
224 return 0;
597603d6
JK		 225}
226
26c53379
TW		 227/* call in cable->lock */
228static int loopback_snd_timer_start(struct loopback_pcm *dpcm)
229{
230 struct loopback_cable *cable = dpcm->cable;
231 int err;
232
233 /* Loopback device has to use same period as timer card. Therefore
234 * wake up for each snd_pcm_period_elapsed() call of timer card.
235 */
236 err = snd_timer_start(cable->snd_timer.instance, 1);
237 if (err < 0) {
238 /* do not report error if trying to start but already
239 * running. For example called by opposite substream
240 * of the same cable
241 */
242 if (err == -EBUSY)
243 return 0;
244
245 pcm_err(dpcm->substream->pcm,
246 "snd_timer_start(%d,%d,%d) failed with %d",
247 cable->snd_timer.id.card,
248 cable->snd_timer.id.device,
249 cable->snd_timer.id.subdevice,
250 err);
251 }
252
253 return err;
254}
255
999fc9f6 256/* call in cable->lock */
8e3bf7cd 257static inline int loopback_jiffies_timer_stop(struct loopback_pcm *dpcm)
597603d6
JK		 258{
259 del_timer(&dpcm->timer);
e74670b6 260 dpcm->timer.expires = 0;
09419f1a
TW		 261
262 return 0;
597603d6
JK		 263}
264
26c53379
TW		 265/* call in cable->lock */
266static int loopback_snd_timer_stop(struct loopback_pcm *dpcm)
267{
268 struct loopback_cable *cable = dpcm->cable;
269 int err;
270
271 /* only stop if both devices (playback and capture) are not running */
272 if (cable->running ^ cable->pause)
273 return 0;
274
275 err = snd_timer_stop(cable->snd_timer.instance);
276 if (err < 0) {
277 pcm_err(dpcm->substream->pcm,
278 "snd_timer_stop(%d,%d,%d) failed with %d",
279 cable->snd_timer.id.card,
280 cable->snd_timer.id.device,
281 cable->snd_timer.id.subdevice,
282 err);
283 }
284
285 return err;
286}
287
8e3bf7cd 288static inline int loopback_jiffies_timer_stop_sync(struct loopback_pcm *dpcm)
67a01afa
TI		 289{
290 del_timer_sync(&dpcm->timer);
09419f1a
TW		 291
292 return 0;
67a01afa
TI		 293}
294
26c53379
TW		 295/* call in loopback->cable_lock */
296static int loopback_snd_timer_close_cable(struct loopback_pcm *dpcm)
297{
298 struct loopback_cable *cable = dpcm->cable;
299
300 /* snd_timer was not opened */
301 if (!cable->snd_timer.instance)
302 return 0;
303
26c53379
TW		 304 /* will only be called from free_cable() when other stream was
305 * already closed. Other stream cannot be reopened as long as
306 * loopback->cable_lock is locked. Therefore no need to lock
307 * cable->lock;
308 */
309 snd_timer_close(cable->snd_timer.instance);
9314e44f 310
6053a712
TI		 311 /* wait till drain work has finished if requested */
312 cancel_work_sync(&cable->snd_timer.event_work);
9314e44f 313
26c53379
TW		 314 snd_timer_instance_free(cable->snd_timer.instance);
315 memset(&cable->snd_timer, 0, sizeof(cable->snd_timer));
316
317 return 0;
318}
319
597603d6
JK		 320static int loopback_check_format(struct loopback_cable *cable, int stream)
321{
b1c73fc8 322 struct snd_pcm_runtime *runtime, *cruntime;
597603d6
JK		 323 struct loopback_setup *setup;
324 struct snd_card *card;
325 int check;
326
327 if (cable->valid != CABLE_VALID_BOTH) {
328 if (stream == SNDRV_PCM_STREAM_PLAYBACK)
329 goto __notify;
330 return 0;
331 }
332 runtime = cable->streams[SNDRV_PCM_STREAM_PLAYBACK]->
333 substream->runtime;
b1c73fc8
JK		 334 cruntime = cable->streams[SNDRV_PCM_STREAM_CAPTURE]->
335 substream->runtime;
336 check = runtime->format != cruntime->format ||
337 runtime->rate != cruntime->rate ||
338 runtime->channels != cruntime->channels;
597603d6
JK		 339 if (!check)
340 return 0;
341 if (stream == SNDRV_PCM_STREAM_CAPTURE) {
342 return -EIO;
343 } else {
344 snd_pcm_stop(cable->streams[SNDRV_PCM_STREAM_CAPTURE]->
345 substream, SNDRV_PCM_STATE_DRAINING);
346 __notify:
347 runtime = cable->streams[SNDRV_PCM_STREAM_PLAYBACK]->
348 substream->runtime;
349 setup = get_setup(cable->streams[SNDRV_PCM_STREAM_PLAYBACK]);
350 card = cable->streams[SNDRV_PCM_STREAM_PLAYBACK]->loopback->card;
351 if (setup->format != runtime->format) {
352 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
353 &setup->format_id);
354 setup->format = runtime->format;
355 }
356 if (setup->rate != runtime->rate) {
357 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
358 &setup->rate_id);
359 setup->rate = runtime->rate;
360 }
361 if (setup->channels != runtime->channels) {
362 snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
363 &setup->channels_id);
364 setup->channels = runtime->channels;
365 }
366 }
367 return 0;
368}
369
370static void loopback_active_notify(struct loopback_pcm *dpcm)
371{
372 snd_ctl_notify(dpcm->loopback->card,
373 SNDRV_CTL_EVENT_MASK_VALUE,
374 &get_setup(dpcm)->active_id);
375}
376
377static int loopback_trigger(struct snd_pcm_substream *substream, int cmd)
378{
379 struct snd_pcm_runtime *runtime = substream->runtime;
380 struct loopback_pcm *dpcm = runtime->private_data;
381 struct loopback_cable *cable = dpcm->cable;
09419f1a 382 int err = 0, stream = 1 << substream->stream;
597603d6
JK		 383
384 switch (cmd) {
385 case SNDRV_PCM_TRIGGER_START:
386 err = loopback_check_format(cable, substream->stream);
387 if (err < 0)
388 return err;
389 dpcm->last_jiffies = jiffies;
390 dpcm->pcm_rate_shift = 0;
b012513c 391 dpcm->last_drift = 0;
dd04bb12 392 spin_lock(&cable->lock);
5de9e45f
JK		 393 cable->running |= stream;
394 cable->pause &= ~stream;
133f3759 395 err = cable->ops->start(dpcm);
999fc9f6 396 spin_unlock(&cable->lock);
597603d6
JK		 397 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
398 loopback_active_notify(dpcm);
399 break;
400 case SNDRV_PCM_TRIGGER_STOP:
dd04bb12 401 spin_lock(&cable->lock);
5de9e45f
JK		 402 cable->running &= ~stream;
403 cable->pause &= ~stream;
133f3759 404 err = cable->ops->stop(dpcm);
999fc9f6 405 spin_unlock(&cable->lock);
597603d6
JK		 406 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
407 loopback_active_notify(dpcm);
408 break;
5de9e45f 409 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
edac8943 410 case SNDRV_PCM_TRIGGER_SUSPEND:
5de9e45f
JK		 411 spin_lock(&cable->lock);
412 cable->pause |= stream;
133f3759 413 err = cable->ops->stop(dpcm);
999fc9f6 414 spin_unlock(&cable->lock);
306a4f3c
RR		 415 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
416 loopback_active_notify(dpcm);
5de9e45f
JK		 417 break;
418 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
edac8943 419 case SNDRV_PCM_TRIGGER_RESUME:
5de9e45f
JK		 420 spin_lock(&cable->lock);
421 dpcm->last_jiffies = jiffies;
422 cable->pause &= ~stream;
133f3759 423 err = cable->ops->start(dpcm);
999fc9f6 424 spin_unlock(&cable->lock);
306a4f3c
RR		 425 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
426 loopback_active_notify(dpcm);
5de9e45f 427 break;
597603d6
JK		 428 default:
429 return -EINVAL;
430 }
09419f1a 431 return err;
597603d6
JK		 432}
433
b1c73fc8
JK		 434static void params_change(struct snd_pcm_substream *substream)
435{
436 struct snd_pcm_runtime *runtime = substream->runtime;
437 struct loopback_pcm *dpcm = runtime->private_data;
438 struct loopback_cable *cable = dpcm->cable;
439
74c34ca1 440 cable->hw.formats = pcm_format_to_bits(runtime->format);
b1c73fc8
JK		 441 cable->hw.rate_min = runtime->rate;
442 cable->hw.rate_max = runtime->rate;
443 cable->hw.channels_min = runtime->channels;
444 cable->hw.channels_max = runtime->channels;
26c53379
TW		 445
446 if (cable->snd_timer.instance) {
447 cable->hw.period_bytes_min =
448 frames_to_bytes(runtime, runtime->period_size);
449 cable->hw.period_bytes_max = cable->hw.period_bytes_min;
450 }
451
b1c73fc8
JK		 452}
453
597603d6
JK		 454static int loopback_prepare(struct snd_pcm_substream *substream)
455{
456 struct snd_pcm_runtime *runtime = substream->runtime;
457 struct loopback_pcm *dpcm = runtime->private_data;
458 struct loopback_cable *cable = dpcm->cable;
09419f1a 459 int err, bps, salign;
597603d6 460
133f3759
TW		 461 if (cable->ops->stop_sync) {
462 err = cable->ops->stop_sync(dpcm);
463 if (err < 0)
464 return err;
465 }
67a01afa 466
50e09084 467 salign = (snd_pcm_format_physical_width(runtime->format) *
597603d6
JK		 468 runtime->channels) / 8;
469 bps = salign * runtime->rate;
470 if (bps <= 0 || salign <= 0)
471 return -EINVAL;
472
473 dpcm->buf_pos = 0;
474 dpcm->pcm_buffer_size = frames_to_bytes(runtime, runtime->buffer_size);
475 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
476 /* clear capture buffer */
477 dpcm->silent_size = dpcm->pcm_buffer_size;
478 snd_pcm_format_set_silence(runtime->format, runtime->dma_area,
479 runtime->buffer_size * runtime->channels);
480 }
481
482 dpcm->irq_pos = 0;
483 dpcm->period_update_pending = 0;
484 dpcm->pcm_bps = bps;
485 dpcm->pcm_salign = salign;
486 dpcm->pcm_period_size = frames_to_bytes(runtime, runtime->period_size);
487
488 mutex_lock(&dpcm->loopback->cable_lock);
b1c73fc8
JK		 489 if (!(cable->valid & ~(1 << substream->stream)) ||
490 (get_setup(dpcm)->notify &&
491 substream->stream == SNDRV_PCM_STREAM_PLAYBACK))
492 params_change(substream);
597603d6
JK		 493 cable->valid |= 1 << substream->stream;
494 mutex_unlock(&dpcm->loopback->cable_lock);
495
496 return 0;
497}
498
499static void clear_capture_buf(struct loopback_pcm *dpcm, unsigned int bytes)
500{
501 struct snd_pcm_runtime *runtime = dpcm->substream->runtime;
502 char *dst = runtime->dma_area;
503 unsigned int dst_off = dpcm->buf_pos;
504
505 if (dpcm->silent_size >= dpcm->pcm_buffer_size)
506 return;
507 if (dpcm->silent_size + bytes > dpcm->pcm_buffer_size)
508 bytes = dpcm->pcm_buffer_size - dpcm->silent_size;
509
510 for (;;) {
511 unsigned int size = bytes;
512 if (dst_off + size > dpcm->pcm_buffer_size)
513 size = dpcm->pcm_buffer_size - dst_off;
514 snd_pcm_format_set_silence(runtime->format, dst + dst_off,
515 bytes_to_frames(runtime, size) *
516 runtime->channels);
517 dpcm->silent_size += size;
518 bytes -= size;
519 if (!bytes)
520 break;
521 dst_off = 0;
522 }
523}
524
525static void copy_play_buf(struct loopback_pcm *play,
526 struct loopback_pcm *capt,
527 unsigned int bytes)
528{
529 struct snd_pcm_runtime *runtime = play->substream->runtime;
20d9a26d 530 char *src = runtime->dma_area;
597603d6
JK		 531 char *dst = capt->substream->runtime->dma_area;
532 unsigned int src_off = play->buf_pos;
533 unsigned int dst_off = capt->buf_pos;
534 unsigned int clear_bytes = 0;
535
536 /* check if playback is draining, trim the capture copy size
537 * when our pointer is at the end of playback ring buffer */
f7efa9b8 538 if (runtime->state == SNDRV_PCM_STATE_DRAINING &&
597603d6
JK		 539 snd_pcm_playback_hw_avail(runtime) < runtime->buffer_size) {
540 snd_pcm_uframes_t appl_ptr, appl_ptr1, diff;
541 appl_ptr = appl_ptr1 = runtime->control->appl_ptr;
542 appl_ptr1 -= appl_ptr1 % runtime->buffer_size;
543 appl_ptr1 += play->buf_pos / play->pcm_salign;
544 if (appl_ptr < appl_ptr1)
545 appl_ptr1 -= runtime->buffer_size;
546 diff = (appl_ptr - appl_ptr1) * play->pcm_salign;
547 if (diff < bytes) {
548 clear_bytes = bytes - diff;
549 bytes = diff;
550 }
551 }
552
553 for (;;) {
554 unsigned int size = bytes;
555 if (src_off + size > play->pcm_buffer_size)
556 size = play->pcm_buffer_size - src_off;
557 if (dst_off + size > capt->pcm_buffer_size)
558 size = capt->pcm_buffer_size - dst_off;
559 memcpy(dst + dst_off, src + src_off, size);
560 capt->silent_size = 0;
561 bytes -= size;
562 if (!bytes)
563 break;
564 src_off = (src_off + size) % play->pcm_buffer_size;
565 dst_off = (dst_off + size) % capt->pcm_buffer_size;
566 }
567
20d9a26d 568 if (clear_bytes > 0) {
597603d6 569 clear_capture_buf(capt, clear_bytes);
20d9a26d
JK		 570 capt->silent_size = 0;
571 }
597603d6
JK		 572}
573
b012513c
JK		 574static inline unsigned int bytepos_delta(struct loopback_pcm *dpcm,
575 unsigned int jiffies_delta)
597603d6 576{
597603d6 577 unsigned long last_pos;
b012513c 578 unsigned int delta;
597603d6
JK		 579
580 last_pos = byte_pos(dpcm, dpcm->irq_pos);
b012513c
JK		 581 dpcm->irq_pos += jiffies_delta * dpcm->pcm_bps;
582 delta = byte_pos(dpcm, dpcm->irq_pos) - last_pos;
583 if (delta >= dpcm->last_drift)
584 delta -= dpcm->last_drift;
585 dpcm->last_drift = 0;
597603d6
JK		 586 if (dpcm->irq_pos >= dpcm->period_size_frac) {
587 dpcm->irq_pos %= dpcm->period_size_frac;
588 dpcm->period_update_pending = 1;
589 }
b012513c
JK		 590 return delta;
591}
592
593static inline void bytepos_finish(struct loopback_pcm *dpcm,
594 unsigned int delta)
595{
596 dpcm->buf_pos += delta;
597 dpcm->buf_pos %= dpcm->pcm_buffer_size;
597603d6
JK		 598}
599
999fc9f6 600/* call in cable->lock */
8e3bf7cd
TW		 601static unsigned int loopback_jiffies_timer_pos_update
602 (struct loopback_cable *cable)
597603d6
JK		 603{
604 struct loopback_pcm *dpcm_play =
605 cable->streams[SNDRV_PCM_STREAM_PLAYBACK];
606 struct loopback_pcm *dpcm_capt =
607 cable->streams[SNDRV_PCM_STREAM_CAPTURE];
3e48940a 608 unsigned long delta_play = 0, delta_capt = 0, cur_jiffies;
b012513c 609 unsigned int running, count1, count2;
597603d6 610
3e48940a 611 cur_jiffies = jiffies;
5de9e45f 612 running = cable->running ^ cable->pause;
dd04bb12 613 if (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) {
3e48940a 614 delta_play = cur_jiffies - dpcm_play->last_jiffies;
597603d6
JK		 615 dpcm_play->last_jiffies += delta_play;
616 }
617
dd04bb12 618 if (running & (1 << SNDRV_PCM_STREAM_CAPTURE)) {
3e48940a 619 delta_capt = cur_jiffies - dpcm_capt->last_jiffies;
597603d6
JK		 620 dpcm_capt->last_jiffies += delta_capt;
621 }
622
98d21df4
TI		 623 if (delta_play == 0 && delta_capt == 0)
624 goto unlock;
597603d6
JK		 625
626 if (delta_play > delta_capt) {
b012513c
JK		 627 count1 = bytepos_delta(dpcm_play, delta_play - delta_capt);
628 bytepos_finish(dpcm_play, count1);
597603d6
JK		 629 delta_play = delta_capt;
630 } else if (delta_play < delta_capt) {
b012513c
JK		 631 count1 = bytepos_delta(dpcm_capt, delta_capt - delta_play);
632 clear_capture_buf(dpcm_capt, count1);
633 bytepos_finish(dpcm_capt, count1);
597603d6
JK		 634 delta_capt = delta_play;
635 }
636
98d21df4
TI		 637 if (delta_play == 0 && delta_capt == 0)
638 goto unlock;
639
597603d6 640 /* note delta_capt == delta_play at this moment */
b012513c
JK		 641 count1 = bytepos_delta(dpcm_play, delta_play);
642 count2 = bytepos_delta(dpcm_capt, delta_capt);
643 if (count1 < count2) {
644 dpcm_capt->last_drift = count2 - count1;
645 count1 = count2;
646 } else if (count1 > count2) {
647 dpcm_play->last_drift = count1 - count2;
648 }
649 copy_play_buf(dpcm_play, dpcm_capt, count1);
650 bytepos_finish(dpcm_play, count1);
651 bytepos_finish(dpcm_capt, count1);
98d21df4 652 unlock:
dd04bb12 653 return running;
597603d6
JK		 654}
655
8e3bf7cd 656static void loopback_jiffies_timer_function(struct timer_list *t)
597603d6 657{
bc47ba90 658 struct loopback_pcm *dpcm = from_timer(dpcm, t, timer);
999fc9f6 659 unsigned long flags;
597603d6 660
999fc9f6 661 spin_lock_irqsave(&dpcm->cable->lock, flags);
8e3bf7cd
TW		 662 if (loopback_jiffies_timer_pos_update(dpcm->cable) &
663 (1 << dpcm->substream->stream)) {
664 loopback_jiffies_timer_start(dpcm);
dd04bb12
JK		 665 if (dpcm->period_update_pending) {
666 dpcm->period_update_pending = 0;
999fc9f6
TI		 667 spin_unlock_irqrestore(&dpcm->cable->lock, flags);
668 /* need to unlock before calling below */
597603d6 669 snd_pcm_period_elapsed(dpcm->substream);
999fc9f6 670 return;
dd04bb12 671 }
597603d6 672 }
999fc9f6 673 spin_unlock_irqrestore(&dpcm->cable->lock, flags);
597603d6
JK		 674}
675
26c53379
TW		 676/* call in cable->lock */
677static int loopback_snd_timer_check_resolution(struct snd_pcm_runtime *runtime,
678 unsigned long resolution)
679{
680 if (resolution != runtime->timer_resolution) {
681 struct loopback_pcm *dpcm = runtime->private_data;
682 struct loopback_cable *cable = dpcm->cable;
683 /* Worst case estimation of possible values for resolution
684 * resolution <= (512 * 1024) frames / 8kHz in nsec
685 * resolution <= 65.536.000.000 nsec
686 *
687 * period_size <= 65.536.000.000 nsec / 1000nsec/usec * 192kHz +
688 * 500.000
689 * period_size <= 12.582.912.000.000 <64bit
690 * / 1.000.000 usec/sec
691 */
692 snd_pcm_uframes_t period_size_usec =
693 resolution / 1000 * runtime->rate;
694 /* round to nearest sample rate */
695 snd_pcm_uframes_t period_size =
696 (period_size_usec + 500 * 1000) / (1000 * 1000);
697
698 pcm_err(dpcm->substream->pcm,
699 "Period size (%lu frames) of loopback device is not corresponding to timer resolution (%lu nsec = %lu frames) of card timer %d,%d,%d. Use period size of %lu frames for loopback device.",
700 runtime->period_size, resolution, period_size,
701 cable->snd_timer.id.card,
702 cable->snd_timer.id.device,
703 cable->snd_timer.id.subdevice,
704 period_size);
705 return -EINVAL;
706 }
707 return 0;
708}
709
710static void loopback_snd_timer_period_elapsed(struct loopback_cable *cable,
711 int event,
712 unsigned long resolution)
713{
714 struct loopback_pcm *dpcm_play, *dpcm_capt;
715 struct snd_pcm_substream *substream_play, *substream_capt;
716 struct snd_pcm_runtime *valid_runtime;
717 unsigned int running, elapsed_bytes;
718 unsigned long flags;
719
720 spin_lock_irqsave(&cable->lock, flags);
721 running = cable->running ^ cable->pause;
722 /* no need to do anything if no stream is running */
723 if (!running) {
724 spin_unlock_irqrestore(&cable->lock, flags);
725 return;
726 }
727
728 dpcm_play = cable->streams[SNDRV_PCM_STREAM_PLAYBACK];
729 dpcm_capt = cable->streams[SNDRV_PCM_STREAM_CAPTURE];
26c53379
TW		 730
731 if (event == SNDRV_TIMER_EVENT_MSTOP) {
732 if (!dpcm_play ||
f7efa9b8 733 dpcm_play->substream->runtime->state !=
26c53379
TW		 734 SNDRV_PCM_STATE_DRAINING) {
735 spin_unlock_irqrestore(&cable->lock, flags);
736 return;
737 }
738 }
739
5061bb70
AG		 740 substream_play = (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) ?
741 dpcm_play->substream : NULL;
742 substream_capt = (running & (1 << SNDRV_PCM_STREAM_CAPTURE)) ?
743 dpcm_capt->substream : NULL;
26c53379
TW		 744 valid_runtime = (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) ?
745 dpcm_play->substream->runtime :
746 dpcm_capt->substream->runtime;
747
748 /* resolution is only valid for SNDRV_TIMER_EVENT_TICK events */
749 if (event == SNDRV_TIMER_EVENT_TICK) {
750 /* The hardware rules guarantee that playback and capture period
751 * are the same. Therefore only one device has to be checked
752 * here.
753 */
754 if (loopback_snd_timer_check_resolution(valid_runtime,
755 resolution) < 0) {
756 spin_unlock_irqrestore(&cable->lock, flags);
757 if (substream_play)
758 snd_pcm_stop_xrun(substream_play);
759 if (substream_capt)
760 snd_pcm_stop_xrun(substream_capt);
761 return;
762 }
763 }
764
765 elapsed_bytes = frames_to_bytes(valid_runtime,
766 valid_runtime->period_size);
767 /* The same timer interrupt is used for playback and capture device */
768 if ((running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) &&
769 (running & (1 << SNDRV_PCM_STREAM_CAPTURE))) {
770 copy_play_buf(dpcm_play, dpcm_capt, elapsed_bytes);
771 bytepos_finish(dpcm_play, elapsed_bytes);
772 bytepos_finish(dpcm_capt, elapsed_bytes);
773 } else if (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) {
774 bytepos_finish(dpcm_play, elapsed_bytes);
775 } else if (running & (1 << SNDRV_PCM_STREAM_CAPTURE)) {
776 clear_capture_buf(dpcm_capt, elapsed_bytes);
777 bytepos_finish(dpcm_capt, elapsed_bytes);
778 }
779 spin_unlock_irqrestore(&cable->lock, flags);
780
781 if (substream_play)
782 snd_pcm_period_elapsed(substream_play);
783 if (substream_capt)
784 snd_pcm_period_elapsed(substream_capt);
785}
786
787static void loopback_snd_timer_function(struct snd_timer_instance *timeri,
788 unsigned long resolution,
789 unsigned long ticks)
790{
791 struct loopback_cable *cable = timeri->callback_data;
792
793 loopback_snd_timer_period_elapsed(cable, SNDRV_TIMER_EVENT_TICK,
794 resolution);
795}
796
6053a712 797static void loopback_snd_timer_work(struct work_struct *work)
26c53379 798{
6053a712 799 struct loopback_cable *cable;
26c53379 800
6053a712 801 cable = container_of(work, struct loopback_cable, snd_timer.event_work);
26c53379
TW		 802 loopback_snd_timer_period_elapsed(cable, SNDRV_TIMER_EVENT_MSTOP, 0);
803}
804
805static void loopback_snd_timer_event(struct snd_timer_instance *timeri,
806 int event,
fcae40c9 807 struct timespec64 *tstamp,
26c53379
TW		 808 unsigned long resolution)
809{
810 /* Do not lock cable->lock here because timer->lock is already hold.
811 * There are other functions which first lock cable->lock and than
812 * timer->lock e.g.
813 * loopback_trigger()
814 * spin_lock(&cable->lock)
815 * loopback_snd_timer_start()
816 * snd_timer_start()
817 * spin_lock(&timer->lock)
818 * Therefore when using the oposit order of locks here it could result
819 * in a deadlock.
820 */
821
822 if (event == SNDRV_TIMER_EVENT_MSTOP) {
823 struct loopback_cable *cable = timeri->callback_data;
824
825 /* sound card of the timer was stopped. Therefore there will not
826 * be any further timer callbacks. Due to this forward audio
827 * data from here if in draining state. When still in running
828 * state the streaming will be aborted by the usual timeout. It
829 * should not be aborted here because may be the timer sound
830 * card does only a recovery and the timer is back soon.
6053a712 831 * This work triggers loopback_snd_timer_work()
26c53379 832 */
6053a712 833 schedule_work(&cable->snd_timer.event_work);
26c53379
TW		 834 }
835}
836
133f3759
TW		 837static void loopback_jiffies_timer_dpcm_info(struct loopback_pcm *dpcm,
838 struct snd_info_buffer *buffer)
839{
840 snd_iprintf(buffer, " update_pending:\t%u\n",
841 dpcm->period_update_pending);
842 snd_iprintf(buffer, " irq_pos:\t\t%u\n", dpcm->irq_pos);
843 snd_iprintf(buffer, " period_frac:\t%u\n", dpcm->period_size_frac);
844 snd_iprintf(buffer, " last_jiffies:\t%lu (%lu)\n",
845 dpcm->last_jiffies, jiffies);
846 snd_iprintf(buffer, " timer_expires:\t%lu\n", dpcm->timer.expires);
847}
848
26c53379
TW		 849static void loopback_snd_timer_dpcm_info(struct loopback_pcm *dpcm,
850 struct snd_info_buffer *buffer)
851{
852 struct loopback_cable *cable = dpcm->cable;
853
854 snd_iprintf(buffer, " sound timer:\thw:%d,%d,%d\n",
855 cable->snd_timer.id.card,
856 cable->snd_timer.id.device,
857 cable->snd_timer.id.subdevice);
858 snd_iprintf(buffer, " timer open:\t\t%s\n",
859 (cable->snd_timer.stream == SNDRV_PCM_STREAM_CAPTURE) ?
860 "capture" : "playback");
861}
862
597603d6
JK		 863static snd_pcm_uframes_t loopback_pointer(struct snd_pcm_substream *substream)
864{
865 struct snd_pcm_runtime *runtime = substream->runtime;
866 struct loopback_pcm *dpcm = runtime->private_data;
999fc9f6 867 snd_pcm_uframes_t pos;
597603d6 868
999fc9f6 869 spin_lock(&dpcm->cable->lock);
133f3759
TW		 870 if (dpcm->cable->ops->pos_update)
871 dpcm->cable->ops->pos_update(dpcm->cable);
999fc9f6
TI		 872 pos = dpcm->buf_pos;
873 spin_unlock(&dpcm->cable->lock);
874 return bytes_to_frames(runtime, pos);
597603d6
JK		 875}
876
b6c0b715 877static const struct snd_pcm_hardware loopback_pcm_hardware =
597603d6
JK		 878{
879 .info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_MMAP |
edac8943
TI		 880 SNDRV_PCM_INFO_MMAP_VALID | SNDRV_PCM_INFO_PAUSE |
881 SNDRV_PCM_INFO_RESUME),
597603d6 882 .formats = (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_BE |
50e09084
TW		 883 SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S24_BE |
884 SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S24_3BE |
597603d6
JK		 885 SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S32_BE |
886 SNDRV_PCM_FMTBIT_FLOAT_LE | SNDRV_PCM_FMTBIT_FLOAT_BE),
887 .rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_192000,
888 .rate_min = 8000,
889 .rate_max = 192000,
890 .channels_min = 1,
891 .channels_max = 32,
892 .buffer_bytes_max = 2 * 1024 * 1024,
893 .period_bytes_min = 64,
0db71023
JK		 894 /* note check overflow in frac_pos() using pcm_rate_shift before
895 changing period_bytes_max value */
896 .period_bytes_max = 1024 * 1024,
597603d6
JK		 897 .periods_min = 1,
898 .periods_max = 1024,
899 .fifo_size = 0,
900};
901
902static void loopback_runtime_free(struct snd_pcm_runtime *runtime)
903{
904 struct loopback_pcm *dpcm = runtime->private_data;
905 kfree(dpcm);
906}
907
597603d6
JK		 908static int loopback_hw_free(struct snd_pcm_substream *substream)
909{
910 struct snd_pcm_runtime *runtime = substream->runtime;
911 struct loopback_pcm *dpcm = runtime->private_data;
912 struct loopback_cable *cable = dpcm->cable;
913
914 mutex_lock(&dpcm->loopback->cable_lock);
915 cable->valid &= ~(1 << substream->stream);
916 mutex_unlock(&dpcm->loopback->cable_lock);
39729889 917 return 0;
597603d6
JK		 918}
919
920static unsigned int get_cable_index(struct snd_pcm_substream *substream)
921{
922 if (!substream->pcm->device)
923 return substream->stream;
924 else
925 return !substream->stream;
926}
927
b1c73fc8
JK		 928static int rule_format(struct snd_pcm_hw_params *params,
929 struct snd_pcm_hw_rule *rule)
930{
898dfe46
TI		 931 struct loopback_pcm *dpcm = rule->private;
932 struct loopback_cable *cable = dpcm->cable;
b088b53e 933 struct snd_mask m;
b1c73fc8 934
b088b53e 935 snd_mask_none(&m);
898dfe46
TI		 936 mutex_lock(&dpcm->loopback->cable_lock);
937 m.bits[0] = (u_int32_t)cable->hw.formats;
938 m.bits[1] = (u_int32_t)(cable->hw.formats >> 32);
939 mutex_unlock(&dpcm->loopback->cable_lock);
b088b53e 940 return snd_mask_refine(hw_param_mask(params, rule->var), &m);
b1c73fc8
JK		 941}
942
943static int rule_rate(struct snd_pcm_hw_params *params,
944 struct snd_pcm_hw_rule *rule)
945{
898dfe46
TI		 946 struct loopback_pcm *dpcm = rule->private;
947 struct loopback_cable *cable = dpcm->cable;
b1c73fc8
JK		 948 struct snd_interval t;
949
898dfe46
TI		 950 mutex_lock(&dpcm->loopback->cable_lock);
951 t.min = cable->hw.rate_min;
952 t.max = cable->hw.rate_max;
953 mutex_unlock(&dpcm->loopback->cable_lock);
b1c73fc8
JK		 954 t.openmin = t.openmax = 0;
955 t.integer = 0;
956 return snd_interval_refine(hw_param_interval(params, rule->var), &t);
957}
958
959static int rule_channels(struct snd_pcm_hw_params *params,
960 struct snd_pcm_hw_rule *rule)
961{
898dfe46
TI		 962 struct loopback_pcm *dpcm = rule->private;
963 struct loopback_cable *cable = dpcm->cable;
b1c73fc8
JK		 964 struct snd_interval t;
965
898dfe46
TI		 966 mutex_lock(&dpcm->loopback->cable_lock);
967 t.min = cable->hw.channels_min;
968 t.max = cable->hw.channels_max;
969 mutex_unlock(&dpcm->loopback->cable_lock);
b1c73fc8
JK		 970 t.openmin = t.openmax = 0;
971 t.integer = 0;
972 return snd_interval_refine(hw_param_interval(params, rule->var), &t);
973}
974
26c53379
TW		 975static int rule_period_bytes(struct snd_pcm_hw_params *params,
976 struct snd_pcm_hw_rule *rule)
977{
978 struct loopback_pcm *dpcm = rule->private;
979 struct loopback_cable *cable = dpcm->cable;
980 struct snd_interval t;
981
982 mutex_lock(&dpcm->loopback->cable_lock);
983 t.min = cable->hw.period_bytes_min;
984 t.max = cable->hw.period_bytes_max;
985 mutex_unlock(&dpcm->loopback->cable_lock);
986 t.openmin = 0;
987 t.openmax = 0;
988 t.integer = 0;
989 return snd_interval_refine(hw_param_interval(params, rule->var), &t);
990}
991
9685347a
TI		 992static void free_cable(struct snd_pcm_substream *substream)
993{
994 struct loopback *loopback = substream->private_data;
995 int dev = get_cable_index(substream);
996 struct loopback_cable *cable;
997
998 cable = loopback->cables[substream->number][dev];
999 if (!cable)
1000 return;
1001 if (cable->streams[!substream->stream]) {
1002 /* other stream is still alive */
8e6b1a72 1003 spin_lock_irq(&cable->lock);
9685347a 1004 cable->streams[substream->stream] = NULL;
8e6b1a72 1005 spin_unlock_irq(&cable->lock);
9685347a 1006 } else {
133f3759
TW		 1007 struct loopback_pcm *dpcm = substream->runtime->private_data;
1008
1009 if (cable->ops && cable->ops->close_cable && dpcm)
1010 cable->ops->close_cable(dpcm);
9685347a
TI		 1011 /* free the cable */
1012 loopback->cables[substream->number][dev] = NULL;
1013 kfree(cable);
1014 }
1015}
1016
133f3759
TW		 1017static int loopback_jiffies_timer_open(struct loopback_pcm *dpcm)
1018{
8e3bf7cd 1019 timer_setup(&dpcm->timer, loopback_jiffies_timer_function, 0);
133f3759
TW		 1020
1021 return 0;
1022}
1023
e714fa93 1024static const struct loopback_ops loopback_jiffies_timer_ops = {
133f3759 1025 .open = loopback_jiffies_timer_open,
8e3bf7cd
TW		 1026 .start = loopback_jiffies_timer_start,
1027 .stop = loopback_jiffies_timer_stop,
1028 .stop_sync = loopback_jiffies_timer_stop_sync,
1029 .close_substream = loopback_jiffies_timer_stop_sync,
1030 .pos_update = loopback_jiffies_timer_pos_update,
133f3759
TW		 1031 .dpcm_info = loopback_jiffies_timer_dpcm_info,
1032};
1033
26c53379
TW		 1034static int loopback_parse_timer_id(const char *str,
1035 struct snd_timer_id *tid)
1036{
1037 /* [<pref>:](<card name>|<card idx>)[{.,}<dev idx>[{.,}<subdev idx>]] */
1038 const char * const sep_dev = ".,";
1039 const char * const sep_pref = ":";
1040 const char *name = str;
1041 char *sep, save = '\0';
1042 int card_idx = 0, dev = 0, subdev = 0;
1043 int err;
1044
1045 sep = strpbrk(str, sep_pref);
1046 if (sep)
1047 name = sep + 1;
1048 sep = strpbrk(name, sep_dev);
1049 if (sep) {
1050 save = *sep;
1051 *sep = '\0';
1052 }
1053 err = kstrtoint(name, 0, &card_idx);
1054 if (err == -EINVAL) {
1055 /* Must be the name, not number */
1056 for (card_idx = 0; card_idx < snd_ecards_limit; card_idx++) {
1057 struct snd_card *card = snd_card_ref(card_idx);
1058
1059 if (card) {
1060 if (!strcmp(card->id, name))
1061 err = 0;
1062 snd_card_unref(card);
1063 }
1064 if (!err)
1065 break;
1066 }
1067 }
1068 if (sep) {
1069 *sep = save;
1070 if (!err) {
1071 char *sep2, save2 = '\0';
1072
1073 sep2 = strpbrk(sep + 1, sep_dev);
1074 if (sep2) {
1075 save2 = *sep2;
1076 *sep2 = '\0';
1077 }
1078 err = kstrtoint(sep + 1, 0, &dev);
1079 if (sep2) {
1080 *sep2 = save2;
1081 if (!err)
1082 err = kstrtoint(sep2 + 1, 0, &subdev);
1083 }
1084 }
1085 }
1086 if (!err && tid) {
1087 tid->card = card_idx;
1088 tid->device = dev;
1089 tid->subdevice = subdev;
1090 }
1091 return err;
1092}
1093
1094/* call in loopback->cable_lock */
1095static int loopback_snd_timer_open(struct loopback_pcm *dpcm)
1096{
1097 int err = 0;
1098 struct snd_timer_id tid = {
1099 .dev_class = SNDRV_TIMER_CLASS_PCM,
1100 .dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION,
1101 };
1102 struct snd_timer_instance *timeri;
1103 struct loopback_cable *cable = dpcm->cable;
1104
26c53379
TW		 1105 /* check if timer was already opened. It is only opened once
1106 * per playback and capture subdevice (aka cable).
1107 */
1108 if (cable->snd_timer.instance)
c037239c 1109 goto exit;
26c53379
TW		 1110
1111 err = loopback_parse_timer_id(dpcm->loopback->timer_source, &tid);
1112 if (err < 0) {
1113 pcm_err(dpcm->substream->pcm,
1114 "Parsing timer source \'%s\' failed with %d",
1115 dpcm->loopback->timer_source, err);
c037239c 1116 goto exit;
26c53379
TW		 1117 }
1118
1119 cable->snd_timer.stream = dpcm->substream->stream;
1120 cable->snd_timer.id = tid;
1121
1122 timeri = snd_timer_instance_new(dpcm->loopback->card->id);
1123 if (!timeri) {
1124 err = -ENOMEM;
c037239c 1125 goto exit;
26c53379 1126 }
6053a712 1127 /* The callback has to be called from another work. If
26c53379
TW		 1128 * SNDRV_TIMER_IFLG_FAST is specified it will be called from the
1129 * snd_pcm_period_elapsed() call of the selected sound card.
1130 * snd_pcm_period_elapsed() helds snd_pcm_stream_lock_irqsave().
1131 * Due to our callback loopback_snd_timer_function() also calls
1132 * snd_pcm_period_elapsed() which calls snd_pcm_stream_lock_irqsave().
1133 * This would end up in a dead lock.
1134 */
1135 timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1136 timeri->callback = loopback_snd_timer_function;
1137 timeri->callback_data = (void *)cable;
1138 timeri->ccallback = loopback_snd_timer_event;
1139
6053a712
TI		 1140 /* initialise a work used for draining */
1141 INIT_WORK(&cable->snd_timer.event_work, loopback_snd_timer_work);
26c53379 1142
c037239c
AG		 1143 /* The mutex loopback->cable_lock is kept locked.
1144 * Therefore snd_timer_open() cannot be called a second time
1145 * by the other device of the same cable.
26c53379
TW		 1146 * Therefore the following issue cannot happen:
1147 * [proc1] Call loopback_timer_open() ->
1148 * Unlock cable->lock for snd_timer_close/open() call
1149 * [proc2] Call loopback_timer_open() -> snd_timer_open(),
1150 * snd_timer_start()
1151 * [proc1] Call snd_timer_open() and overwrite running timer
1152 * instance
1153 */
26c53379 1154 err = snd_timer_open(timeri, &cable->snd_timer.id, current->pid);
26c53379
TW		 1155 if (err < 0) {
1156 pcm_err(dpcm->substream->pcm,
1157 "snd_timer_open (%d,%d,%d) failed with %d",
1158 cable->snd_timer.id.card,
1159 cable->snd_timer.id.device,
1160 cable->snd_timer.id.subdevice,
1161 err);
1162 snd_timer_instance_free(timeri);
c037239c 1163 goto exit;
26c53379
TW		 1164 }
1165
1166 cable->snd_timer.instance = timeri;
1167
c037239c 1168exit:
26c53379
TW		 1169 return err;
1170}
1171
1172/* stop_sync() is not required for sound timer because it does not need to be
1173 * restarted in loopback_prepare() on Xrun recovery
1174 */
e714fa93 1175static const struct loopback_ops loopback_snd_timer_ops = {
26c53379
TW		 1176 .open = loopback_snd_timer_open,
1177 .start = loopback_snd_timer_start,
1178 .stop = loopback_snd_timer_stop,
1179 .close_cable = loopback_snd_timer_close_cable,
1180 .dpcm_info = loopback_snd_timer_dpcm_info,
1181};
1182
597603d6
JK		 1183static int loopback_open(struct snd_pcm_substream *substream)
1184{
1185 struct snd_pcm_runtime *runtime = substream->runtime;
1186 struct loopback *loopback = substream->private_data;
1187 struct loopback_pcm *dpcm;
9685347a 1188 struct loopback_cable *cable = NULL;
597603d6
JK		 1189 int err = 0;
1190 int dev = get_cable_index(substream);
1191
1192 mutex_lock(&loopback->cable_lock);
1193 dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
1194 if (!dpcm) {
1195 err = -ENOMEM;
1196 goto unlock;
1197 }
1198 dpcm->loopback = loopback;
1199 dpcm->substream = substream;
597603d6
JK		 1200
1201 cable = loopback->cables[substream->number][dev];
1202 if (!cable) {
1203 cable = kzalloc(sizeof(*cable), GFP_KERNEL);
1204 if (!cable) {
597603d6
JK		 1205 err = -ENOMEM;
1206 goto unlock;
1207 }
1208 spin_lock_init(&cable->lock);
1209 cable->hw = loopback_pcm_hardware;
26c53379
TW		 1210 if (loopback->timer_source)
1211 cable->ops = &loopback_snd_timer_ops;
1212 else
1213 cable->ops = &loopback_jiffies_timer_ops;
597603d6
JK		 1214 loopback->cables[substream->number][dev] = cable;
1215 }
1216 dpcm->cable = cable;
133f3759
TW		 1217 runtime->private_data = dpcm;
1218
1219 if (cable->ops->open) {
1220 err = cable->ops->open(dpcm);
1221 if (err < 0)
1222 goto unlock;
1223 }
597603d6
JK		 1224
1225 snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
1226
b1c73fc8
JK		 1227 /* use dynamic rules based on actual runtime->hw values */
1228 /* note that the default rules created in the PCM midlevel code */
1229 /* are cached -> they do not reflect the actual state */
1230 err = snd_pcm_hw_rule_add(runtime, 0,
1231 SNDRV_PCM_HW_PARAM_FORMAT,
898dfe46 1232 rule_format, dpcm,
b1c73fc8
JK		 1233 SNDRV_PCM_HW_PARAM_FORMAT, -1);
1234 if (err < 0)
1235 goto unlock;
1236 err = snd_pcm_hw_rule_add(runtime, 0,
1237 SNDRV_PCM_HW_PARAM_RATE,
898dfe46 1238 rule_rate, dpcm,
b1c73fc8
JK		 1239 SNDRV_PCM_HW_PARAM_RATE, -1);
1240 if (err < 0)
1241 goto unlock;
1242 err = snd_pcm_hw_rule_add(runtime, 0,
1243 SNDRV_PCM_HW_PARAM_CHANNELS,
898dfe46 1244 rule_channels, dpcm,
b1c73fc8
JK		 1245 SNDRV_PCM_HW_PARAM_CHANNELS, -1);
1246 if (err < 0)
1247 goto unlock;
1248
26c53379
TW		 1249 /* In case of sound timer the period time of both devices of the same
1250 * loop has to be the same.
1251 * This rule only takes effect if a sound timer was chosen
1252 */
1253 if (cable->snd_timer.instance) {
1254 err = snd_pcm_hw_rule_add(runtime, 0,
1255 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
1256 rule_period_bytes, dpcm,
1257 SNDRV_PCM_HW_PARAM_PERIOD_BYTES, -1);
1258 if (err < 0)
1259 goto unlock;
1260 }
1261
133f3759
TW		 1262 /* loopback_runtime_free() has not to be called if kfree(dpcm) was
1263 * already called here. Otherwise it will end up with a double free.
1264 */
597603d6 1265 runtime->private_free = loopback_runtime_free;
b1c73fc8 1266 if (get_notify(dpcm))
597603d6 1267 runtime->hw = loopback_pcm_hardware;
b1c73fc8 1268 else
597603d6 1269 runtime->hw = cable->hw;
8e6b1a72
TI		 1270
1271 spin_lock_irq(&cable->lock);
1272 cable->streams[substream->stream] = dpcm;
1273 spin_unlock_irq(&cable->lock);
1274
597603d6 1275 unlock:
9685347a
TI		 1276 if (err < 0) {
1277 free_cable(substream);
1278 kfree(dpcm);
1279 }
597603d6
JK		 1280 mutex_unlock(&loopback->cable_lock);
1281 return err;
1282}
1283
1284static int loopback_close(struct snd_pcm_substream *substream)
1285{
1286 struct loopback *loopback = substream->private_data;
1287 struct loopback_pcm *dpcm = substream->runtime->private_data;
133f3759 1288 int err = 0;
597603d6 1289
133f3759
TW		 1290 if (dpcm->cable->ops->close_substream)
1291 err = dpcm->cable->ops->close_substream(dpcm);
597603d6 1292 mutex_lock(&loopback->cable_lock);
9685347a 1293 free_cable(substream);
597603d6 1294 mutex_unlock(&loopback->cable_lock);
133f3759 1295 return err;
597603d6
JK		 1296}
1297
9f88058e 1298static const struct snd_pcm_ops loopback_pcm_ops = {
597603d6
JK		 1299 .open = loopback_open,
1300 .close = loopback_close,
597603d6
JK		 1301 .hw_free = loopback_hw_free,
1302 .prepare = loopback_prepare,
1303 .trigger = loopback_trigger,
1304 .pointer = loopback_pointer,
1305};
1306
fbbb01a1
BP		 1307static int loopback_pcm_new(struct loopback *loopback,
1308 int device, int substreams)
597603d6
JK		 1309{
1310 struct snd_pcm *pcm;
1311 int err;
1312
1313 err = snd_pcm_new(loopback->card, "Loopback PCM", device,
1314 substreams, substreams, &pcm);
1315 if (err < 0)
1316 return err;
9f88058e
TI		 1317 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &loopback_pcm_ops);
1318 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &loopback_pcm_ops);
39729889 1319 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC, NULL, 0, 0);
597603d6
JK		 1320
1321 pcm->private_data = loopback;
1322 pcm->info_flags = 0;
1323 strcpy(pcm->name, "Loopback PCM");
1324
1325 loopback->pcm[device] = pcm;
597603d6
JK		 1326 return 0;
1327}
1328
1329static int loopback_rate_shift_info(struct snd_kcontrol *kcontrol,
1330 struct snd_ctl_elem_info *uinfo)
1331{
1332 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1333 uinfo->count = 1;
1334 uinfo->value.integer.min = 80000;
1335 uinfo->value.integer.max = 120000;
1336 uinfo->value.integer.step = 1;
1337 return 0;
1338}
1339
1340static int loopback_rate_shift_get(struct snd_kcontrol *kcontrol,
1341 struct snd_ctl_elem_value *ucontrol)
1342{
1343 struct loopback *loopback = snd_kcontrol_chip(kcontrol);
1344
76b3421b 1345 mutex_lock(&loopback->cable_lock);
597603d6
JK		 1346 ucontrol->value.integer.value[0] =
1347 loopback->setup[kcontrol->id.subdevice]
1348 [kcontrol->id.device].rate_shift;
76b3421b 1349 mutex_unlock(&loopback->cable_lock);
597603d6
JK		 1350 return 0;
1351}
1352
1353static int loopback_rate_shift_put(struct snd_kcontrol *kcontrol,
1354 struct snd_ctl_elem_value *ucontrol)
1355{
1356 struct loopback *loopback = snd_kcontrol_chip(kcontrol);
1357 unsigned int val;
1358 int change = 0;
1359
1360 val = ucontrol->value.integer.value[0];
1361 if (val < 80000)
1362 val = 80000;
1363 if (val > 120000)
1364 val = 120000;
1365 mutex_lock(&loopback->cable_lock);
1366 if (val != loopback->setup[kcontrol->id.subdevice]
1367 [kcontrol->id.device].rate_shift) {
1368 loopback->setup[kcontrol->id.subdevice]
1369 [kcontrol->id.device].rate_shift = val;
1370 change = 1;
1371 }
1372 mutex_unlock(&loopback->cable_lock);
1373 return change;
1374}
1375
1376static int loopback_notify_get(struct snd_kcontrol *kcontrol,
1377 struct snd_ctl_elem_value *ucontrol)
1378{
1379 struct loopback *loopback = snd_kcontrol_chip(kcontrol);
1380
76b3421b 1381 mutex_lock(&loopback->cable_lock);
597603d6
JK		 1382 ucontrol->value.integer.value[0] =
1383 loopback->setup[kcontrol->id.subdevice]
1384 [kcontrol->id.device].notify;
76b3421b 1385 mutex_unlock(&loopback->cable_lock);
597603d6
JK		 1386 return 0;
1387}
1388
1389static int loopback_notify_put(struct snd_kcontrol *kcontrol,
1390 struct snd_ctl_elem_value *ucontrol)
1391{
1392 struct loopback *loopback = snd_kcontrol_chip(kcontrol);
1393 unsigned int val;
1394 int change = 0;
1395
1396 val = ucontrol->value.integer.value[0] ? 1 : 0;
76b3421b 1397 mutex_lock(&loopback->cable_lock);
597603d6
JK		 1398 if (val != loopback->setup[kcontrol->id.subdevice]
1399 [kcontrol->id.device].notify) {
1400 loopback->setup[kcontrol->id.subdevice]
1401 [kcontrol->id.device].notify = val;
1402 change = 1;
1403 }
76b3421b 1404 mutex_unlock(&loopback->cable_lock);
597603d6
JK		 1405 return change;
1406}
1407
1408static int loopback_active_get(struct snd_kcontrol *kcontrol,
1409 struct snd_ctl_elem_value *ucontrol)
1410{
1411 struct loopback *loopback = snd_kcontrol_chip(kcontrol);
76b3421b
TI		 1412 struct loopback_cable *cable;
1413
597603d6
JK		 1414 unsigned int val = 0;
1415
76b3421b
TI		 1416 mutex_lock(&loopback->cable_lock);
1417 cable = loopback->cables[kcontrol->id.subdevice][kcontrol->id.device ^ 1];
306a4f3c
RR		 1418 if (cable != NULL) {
1419 unsigned int running = cable->running ^ cable->pause;
1420
1421 val = (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) ? 1 : 0;
1422 }
76b3421b 1423 mutex_unlock(&loopback->cable_lock);
597603d6
JK		 1424 ucontrol->value.integer.value[0] = val;
1425 return 0;
1426}
1427
1428static int loopback_format_info(struct snd_kcontrol *kcontrol,
1429 struct snd_ctl_elem_info *uinfo)
1430{
1431 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1432 uinfo->count = 1;
1433 uinfo->value.integer.min = 0;
8c356c52 1434 uinfo->value.integer.max = (__force int)SNDRV_PCM_FORMAT_LAST;
597603d6
JK		 1435 uinfo->value.integer.step = 1;
1436 return 0;
1437}
1438
1439static int loopback_format_get(struct snd_kcontrol *kcontrol,
1440 struct snd_ctl_elem_value *ucontrol)
1441{
1442 struct loopback *loopback = snd_kcontrol_chip(kcontrol);
1443
1444 ucontrol->value.integer.value[0] =
8c356c52 1445 (__force int)loopback->setup[kcontrol->id.subdevice]
597603d6
JK		 1446 [kcontrol->id.device].format;
1447 return 0;
1448}
1449
1450static int loopback_rate_info(struct snd_kcontrol *kcontrol,
1451 struct snd_ctl_elem_info *uinfo)
1452{
1453 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1454 uinfo->count = 1;
1455 uinfo->value.integer.min = 0;
1456 uinfo->value.integer.max = 192000;
1457 uinfo->value.integer.step = 1;
1458 return 0;
1459}
1460
1461static int loopback_rate_get(struct snd_kcontrol *kcontrol,
1462 struct snd_ctl_elem_value *ucontrol)
1463{
1464 struct loopback *loopback = snd_kcontrol_chip(kcontrol);
1465
76b3421b 1466 mutex_lock(&loopback->cable_lock);
597603d6
JK		 1467 ucontrol->value.integer.value[0] =
1468 loopback->setup[kcontrol->id.subdevice]
1469 [kcontrol->id.device].rate;
76b3421b 1470 mutex_unlock(&loopback->cable_lock);
597603d6
JK		 1471 return 0;
1472}
1473
1474static int loopback_channels_info(struct snd_kcontrol *kcontrol,
1475 struct snd_ctl_elem_info *uinfo)
1476{
1477 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1478 uinfo->count = 1;
1479 uinfo->value.integer.min = 1;
1480 uinfo->value.integer.max = 1024;
1481 uinfo->value.integer.step = 1;
1482 return 0;
1483}
1484
1485static int loopback_channels_get(struct snd_kcontrol *kcontrol,
1486 struct snd_ctl_elem_value *ucontrol)
1487{
1488 struct loopback *loopback = snd_kcontrol_chip(kcontrol);
1489
76b3421b 1490 mutex_lock(&loopback->cable_lock);
597603d6
JK		 1491 ucontrol->value.integer.value[0] =
1492 loopback->setup[kcontrol->id.subdevice]
1446c5fb 1493 [kcontrol->id.device].channels;
76b3421b 1494 mutex_unlock(&loopback->cable_lock);
597603d6
JK		 1495 return 0;
1496}
1497
2eccd408 1498static const struct snd_kcontrol_new loopback_controls[] = {
597603d6
JK		 1499{
1500 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
1501 .name = "PCM Rate Shift 100000",
1502 .info = loopback_rate_shift_info,
1503 .get = loopback_rate_shift_get,
1504 .put = loopback_rate_shift_put,
1505},
1506{
1507 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
1508 .name = "PCM Notify",
1509 .info = snd_ctl_boolean_mono_info,
1510 .get = loopback_notify_get,
1511 .put = loopback_notify_put,
1512},
1513#define ACTIVE_IDX 2
1514{
1515 .access = SNDRV_CTL_ELEM_ACCESS_READ,
1516 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
1517 .name = "PCM Slave Active",
1518 .info = snd_ctl_boolean_mono_info,
1519 .get = loopback_active_get,
1520},
1521#define FORMAT_IDX 3
1522{
1523 .access = SNDRV_CTL_ELEM_ACCESS_READ,
1524 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
1525 .name = "PCM Slave Format",
1526 .info = loopback_format_info,
1527 .get = loopback_format_get
1528},
1529#define RATE_IDX 4
1530{
1531 .access = SNDRV_CTL_ELEM_ACCESS_READ,
1532 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
1533 .name = "PCM Slave Rate",
1534 .info = loopback_rate_info,
1535 .get = loopback_rate_get
1536},
1537#define CHANNELS_IDX 5
1538{
1539 .access = SNDRV_CTL_ELEM_ACCESS_READ,
1540 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
1541 .name = "PCM Slave Channels",
1542 .info = loopback_channels_info,
1543 .get = loopback_channels_get
1544}
1545};
1546
fbbb01a1 1547static int loopback_mixer_new(struct loopback *loopback, int notify)
597603d6
JK		 1548{
1549 struct snd_card *card = loopback->card;
1550 struct snd_pcm *pcm;
1551 struct snd_kcontrol *kctl;
1552 struct loopback_setup *setup;
1553 int err, dev, substr, substr_count, idx;
1554
1555 strcpy(card->mixername, "Loopback Mixer");
1556 for (dev = 0; dev < 2; dev++) {
1557 pcm = loopback->pcm[dev];
1558 substr_count =
1559 pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count;
1560 for (substr = 0; substr < substr_count; substr++) {
1561 setup = &loopback->setup[substr][dev];
1562 setup->notify = notify;
1563 setup->rate_shift = NO_PITCH;
1564 setup->format = SNDRV_PCM_FORMAT_S16_LE;
1565 setup->rate = 48000;
1566 setup->channels = 2;
1567 for (idx = 0; idx < ARRAY_SIZE(loopback_controls);
1568 idx++) {
1569 kctl = snd_ctl_new1(&loopback_controls[idx],
1570 loopback);
1571 if (!kctl)
1572 return -ENOMEM;
1573 kctl->id.device = dev;
1574 kctl->id.subdevice = substr;
168632a4
JH		 1575
1576 /* Add the control before copying the id so that
1577 * the numid field of the id is set in the copy.
1578 */
1579 err = snd_ctl_add(card, kctl);
1580 if (err < 0)
1581 return err;
1582
597603d6
JK		 1583 switch (idx) {
1584 case ACTIVE_IDX:
1585 setup->active_id = kctl->id;
1586 break;
1587 case FORMAT_IDX:
1588 setup->format_id = kctl->id;
1589 break;
1590 case RATE_IDX:
1591 setup->rate_id = kctl->id;
1592 break;
1593 case CHANNELS_IDX:
1594 setup->channels_id = kctl->id;
1595 break;
1596 default:
1597 break;
1598 }
597603d6
JK		 1599 }
1600 }
1601 }
1602 return 0;
1603}
1604
e74670b6
JK		 1605static void print_dpcm_info(struct snd_info_buffer *buffer,
1606 struct loopback_pcm *dpcm,
1607 const char *id)
1608{
1609 snd_iprintf(buffer, " %s\n", id);
1610 if (dpcm == NULL) {
1611 snd_iprintf(buffer, " inactive\n");
1612 return;
1613 }
1614 snd_iprintf(buffer, " buffer_size:\t%u\n", dpcm->pcm_buffer_size);
1615 snd_iprintf(buffer, " buffer_pos:\t\t%u\n", dpcm->buf_pos);
1616 snd_iprintf(buffer, " silent_size:\t%u\n", dpcm->silent_size);
1617 snd_iprintf(buffer, " period_size:\t%u\n", dpcm->pcm_period_size);
1618 snd_iprintf(buffer, " bytes_per_sec:\t%u\n", dpcm->pcm_bps);
1619 snd_iprintf(buffer, " sample_align:\t%u\n", dpcm->pcm_salign);
1620 snd_iprintf(buffer, " rate_shift:\t\t%u\n", dpcm->pcm_rate_shift);
133f3759
TW		 1621 if (dpcm->cable->ops->dpcm_info)
1622 dpcm->cable->ops->dpcm_info(dpcm, buffer);
e74670b6
JK		 1623}
1624
1625static void print_substream_info(struct snd_info_buffer *buffer,
1626 struct loopback *loopback,
1627 int sub,
1628 int num)
1629{
1630 struct loopback_cable *cable = loopback->cables[sub][num];
1631
1632 snd_iprintf(buffer, "Cable %i substream %i:\n", num, sub);
1633 if (cable == NULL) {
1634 snd_iprintf(buffer, " inactive\n");
1635 return;
1636 }
1637 snd_iprintf(buffer, " valid: %u\n", cable->valid);
1638 snd_iprintf(buffer, " running: %u\n", cable->running);
5de9e45f 1639 snd_iprintf(buffer, " pause: %u\n", cable->pause);
e74670b6
JK		 1640 print_dpcm_info(buffer, cable->streams[0], "Playback");
1641 print_dpcm_info(buffer, cable->streams[1], "Capture");
1642}
1643
1644static void print_cable_info(struct snd_info_entry *entry,
1645 struct snd_info_buffer *buffer)
1646{
1647 struct loopback *loopback = entry->private_data;
1648 int sub, num;
1649
1650 mutex_lock(&loopback->cable_lock);
1651 num = entry->name[strlen(entry->name)-1];
1652 num = num == '0' ? 0 : 1;
1653 for (sub = 0; sub < MAX_PCM_SUBSTREAMS; sub++)
1654 print_substream_info(buffer, loopback, sub, num);
1655 mutex_unlock(&loopback->cable_lock);
1656}
1657
c6ae9960 1658static int loopback_cable_proc_new(struct loopback *loopback, int cidx)
e74670b6
JK		 1659{
1660 char name[32];
e74670b6
JK		 1661
1662 snprintf(name, sizeof(name), "cable#%d", cidx);
815d808c
TI		 1663 return snd_card_ro_proc_new(loopback->card, name, loopback,
1664 print_cable_info);
e74670b6
JK		 1665}
1666
26c53379
TW		 1667static void loopback_set_timer_source(struct loopback *loopback,
1668 const char *value)
1669{
1670 if (loopback->timer_source) {
1671 devm_kfree(loopback->card->dev, loopback->timer_source);
1672 loopback->timer_source = NULL;
1673 }
1674 if (value && *value)
1675 loopback->timer_source = devm_kstrdup(loopback->card->dev,
1676 value, GFP_KERNEL);
1677}
1678
c6ae9960
AG		 1679static void print_timer_source_info(struct snd_info_entry *entry,
1680 struct snd_info_buffer *buffer)
1681{
1682 struct loopback *loopback = entry->private_data;
1683
1684 mutex_lock(&loopback->cable_lock);
1685 snd_iprintf(buffer, "%s\n",
1686 loopback->timer_source ? loopback->timer_source : "");
1687 mutex_unlock(&loopback->cable_lock);
1688}
1689
1690static void change_timer_source_info(struct snd_info_entry *entry,
1691 struct snd_info_buffer *buffer)
1692{
1693 struct loopback *loopback = entry->private_data;
1694 char line[64];
1695
1696 mutex_lock(&loopback->cable_lock);
1697 if (!snd_info_get_line(buffer, line, sizeof(line)))
1698 loopback_set_timer_source(loopback, strim(line));
1699 mutex_unlock(&loopback->cable_lock);
1700}
1701
1702static int loopback_timer_source_proc_new(struct loopback *loopback)
1703{
1704 return snd_card_rw_proc_new(loopback->card, "timer_source", loopback,
1705 print_timer_source_info,
1706 change_timer_source_info);
1707}
1708
fbbb01a1 1709static int loopback_probe(struct platform_device *devptr)
597603d6
JK		 1710{
1711 struct snd_card *card;
1712 struct loopback *loopback;
1713 int dev = devptr->id;
1714 int err;
1715
b072e65a
TI		 1716 err = snd_devm_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
1717 sizeof(struct loopback), &card);
597603d6
JK		 1718 if (err < 0)
1719 return err;
1720 loopback = card->private_data;
1721
1722 if (pcm_substreams[dev] < 1)
1723 pcm_substreams[dev] = 1;
1724 if (pcm_substreams[dev] > MAX_PCM_SUBSTREAMS)
1725 pcm_substreams[dev] = MAX_PCM_SUBSTREAMS;
1726
1727 loopback->card = card;
26c53379
TW		 1728 loopback_set_timer_source(loopback, timer_source[dev]);
1729
597603d6
JK		 1730 mutex_init(&loopback->cable_lock);
1731
1732 err = loopback_pcm_new(loopback, 0, pcm_substreams[dev]);
1733 if (err < 0)
b072e65a 1734 return err;
597603d6
JK		 1735 err = loopback_pcm_new(loopback, 1, pcm_substreams[dev]);
1736 if (err < 0)
b072e65a 1737 return err;
597603d6
JK		 1738 err = loopback_mixer_new(loopback, pcm_notify[dev] ? 1 : 0);
1739 if (err < 0)
b072e65a 1740 return err;
c6ae9960
AG		 1741 loopback_cable_proc_new(loopback, 0);
1742 loopback_cable_proc_new(loopback, 1);
1743 loopback_timer_source_proc_new(loopback);
597603d6
JK		 1744 strcpy(card->driver, "Loopback");
1745 strcpy(card->shortname, "Loopback");
1746 sprintf(card->longname, "Loopback %i", dev + 1);
1747 err = snd_card_register(card);
b072e65a
TI		 1748 if (err < 0)
1749 return err;
1750 platform_set_drvdata(devptr, card);
597603d6
JK		 1751 return 0;
1752}
1753
d34e4e00 1754#ifdef CONFIG_PM_SLEEP
284e7ca7 1755static int loopback_suspend(struct device *pdev)
597603d6 1756{
284e7ca7 1757 struct snd_card *card = dev_get_drvdata(pdev);
597603d6
JK		 1758
1759 snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
597603d6
JK		 1760 return 0;
1761}
1762
284e7ca7 1763static int loopback_resume(struct device *pdev)
597603d6 1764{
284e7ca7 1765 struct snd_card *card = dev_get_drvdata(pdev);
597603d6
JK		 1766
1767 snd_power_change_state(card, SNDRV_CTL_POWER_D0);
1768 return 0;
1769}
284e7ca7
TI		 1770
1771static SIMPLE_DEV_PM_OPS(loopback_pm, loopback_suspend, loopback_resume);
1772#define LOOPBACK_PM_OPS &loopback_pm
1773#else
1774#define LOOPBACK_PM_OPS NULL
597603d6
JK		 1775#endif
1776
1777#define SND_LOOPBACK_DRIVER "snd_aloop"
1778
1779static struct platform_driver loopback_driver = {
1780 .probe = loopback_probe,
597603d6 1781 .driver = {
8bf01d8a 1782 .name = SND_LOOPBACK_DRIVER,
284e7ca7 1783 .pm = LOOPBACK_PM_OPS,
597603d6
JK		 1784 },
1785};
1786
1787static void loopback_unregister_all(void)
1788{
1789 int i;
1790
1791 for (i = 0; i < ARRAY_SIZE(devices); ++i)
1792 platform_device_unregister(devices[i]);
1793 platform_driver_unregister(&loopback_driver);
1794}
1795
1796static int __init alsa_card_loopback_init(void)
1797{
1798 int i, err, cards;
1799
1800 err = platform_driver_register(&loopback_driver);
1801 if (err < 0)
1802 return err;
1803
1804
1805 cards = 0;
1806 for (i = 0; i < SNDRV_CARDS; i++) {
1807 struct platform_device *device;
1808 if (!enable[i])
1809 continue;
1810 device = platform_device_register_simple(SND_LOOPBACK_DRIVER,
1811 i, NULL, 0);
1812 if (IS_ERR(device))
1813 continue;
1814 if (!platform_get_drvdata(device)) {
1815 platform_device_unregister(device);
1816 continue;
1817 }
1818 devices[i] = device;
1819 cards++;
1820 }
1821 if (!cards) {
1822#ifdef MODULE
1823 printk(KERN_ERR "aloop: No loopback enabled\n");
1824#endif
1825 loopback_unregister_all();
1826 return -ENODEV;
1827 }
1828 return 0;
1829}
1830
1831static void __exit alsa_card_loopback_exit(void)
1832{
1833 loopback_unregister_all();
1834}
1835
1836module_init(alsa_card_loopback_init)
1837module_exit(alsa_card_loopback_exit)
Linux 6.x block layer and io_uring tree(s)