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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * u_audio.c -- interface to USB gadget "ALSA sound card" utilities
4 *
5 * Copyright (C) 2016
6 * Author: Ruslan Bilovol <ruslan.bilovol@gmail.com>
7 *
8 * Sound card implementation was cut-and-pasted with changes
9 * from f_uac2.c and has:
10 * Copyright (C) 2011
11 * Yadwinder Singh (yadi.brar01@gmail.com)
12 * Jaswinder Singh (jaswinder.singh@linaro.org)
13 */
14
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <sound/core.h>
18#include <sound/pcm.h>
19#include <sound/pcm_params.h>
20#include <sound/control.h>
21#include <sound/tlv.h>
22#include <linux/usb/audio.h>
23
24#include "u_audio.h"
25
26#define BUFF_SIZE_MAX (PAGE_SIZE * 16)
27#define PRD_SIZE_MAX PAGE_SIZE
28#define MIN_PERIODS 4
29
30enum {
31 UAC_FBACK_CTRL,
32 UAC_P_PITCH_CTRL,
33 UAC_MUTE_CTRL,
34 UAC_VOLUME_CTRL,
35 UAC_RATE_CTRL,
36};
37
38/* Runtime data params for one stream */
39struct uac_rtd_params {
40 struct snd_uac_chip *uac; /* parent chip */
41 bool ep_enabled; /* if the ep is enabled */
42
43 struct snd_pcm_substream *ss;
44
45 /* Ring buffer */
46 ssize_t hw_ptr;
47
48 void *rbuf;
49
50 unsigned int pitch; /* Stream pitch ratio to 1000000 */
51 unsigned int max_psize; /* MaxPacketSize of endpoint */
52
53 struct usb_request **reqs;
54
55 struct usb_request *req_fback; /* Feedback endpoint request */
56 bool fb_ep_enabled; /* if the ep is enabled */
57
58 /* Volume/Mute controls and their state */
59 int fu_id; /* Feature Unit ID */
60 struct snd_kcontrol *snd_kctl_volume;
61 struct snd_kcontrol *snd_kctl_mute;
62 s16 volume_min, volume_max, volume_res;
63 s16 volume;
64 int mute;
65
66 struct snd_kcontrol *snd_kctl_rate; /* read-only current rate */
67 int srate; /* selected samplerate */
68 int active; /* playback/capture running */
69
70 spinlock_t lock; /* lock for control transfers */
71
72};
73
74struct snd_uac_chip {
75 struct g_audio *audio_dev;
76
77 struct uac_rtd_params p_prm;
78 struct uac_rtd_params c_prm;
79
80 struct snd_card *card;
81 struct snd_pcm *pcm;
82
83 /* pre-calculated values for playback iso completion */
84 unsigned long long p_residue_mil;
85 unsigned int p_interval;
86 unsigned int p_framesize;
87};
88
89static const struct snd_pcm_hardware uac_pcm_hardware = {
90 .info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER
91 | SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID
92 | SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME,
93 .rates = SNDRV_PCM_RATE_CONTINUOUS,
94 .periods_max = BUFF_SIZE_MAX / PRD_SIZE_MAX,
95 .buffer_bytes_max = BUFF_SIZE_MAX,
96 .period_bytes_max = PRD_SIZE_MAX,
97 .periods_min = MIN_PERIODS,
98};
99
100static void u_audio_set_fback_frequency(enum usb_device_speed speed,
101 struct usb_ep *out_ep,
102 unsigned long long freq,
103 unsigned int pitch,
104 void *buf)
105{
106 u32 ff = 0;
107 const struct usb_endpoint_descriptor *ep_desc;
108
109 /*
110 * Because the pitch base is 1000000, the final divider here
111 * will be 1000 * 1000000 = 1953125 << 9
112 *
113 * Instead of dealing with big numbers lets fold this 9 left shift
114 */
115
116 if (speed == USB_SPEED_FULL) {
117 /*
118 * Full-speed feedback endpoints report frequency
119 * in samples/frame
120 * Format is encoded in Q10.10 left-justified in the 24 bits,
121 * so that it has a Q10.14 format.
122 *
123 * ff = (freq << 14) / 1000
124 */
125 freq <<= 5;
126 } else {
127 /*
128 * High-speed feedback endpoints report frequency
129 * in samples/microframe.
130 * Format is encoded in Q12.13 fitted into four bytes so that
131 * the binary point is located between the second and the third
132 * byte fromat (that is Q16.16)
133 *
134 * ff = (freq << 16) / 8000
135 *
136 * Win10 and OSX UAC2 drivers require number of samples per packet
137 * in order to honor the feedback value.
138 * Linux snd-usb-audio detects the applied bit-shift automatically.
139 */
140 ep_desc = out_ep->desc;
141 freq <<= 4 + (ep_desc->bInterval - 1);
142 }
143
144 ff = DIV_ROUND_CLOSEST_ULL((freq * pitch), 1953125);
145
146 *(__le32 *)buf = cpu_to_le32(ff);
147}
148
149static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
150{
151 unsigned int pending;
152 unsigned int hw_ptr;
153 int status = req->status;
154 struct snd_pcm_substream *substream;
155 struct snd_pcm_runtime *runtime;
156 struct uac_rtd_params *prm = req->context;
157 struct snd_uac_chip *uac = prm->uac;
158 unsigned int frames, p_pktsize;
159 unsigned long long pitched_rate_mil, p_pktsize_residue_mil,
160 residue_frames_mil, div_result;
161
162 /* i/f shutting down */
163 if (!prm->ep_enabled) {
164 usb_ep_free_request(ep, req);
165 return;
166 }
167
168 if (req->status == -ESHUTDOWN)
169 return;
170
171 /*
172 * We can't really do much about bad xfers.
173 * Afterall, the ISOCH xfers could fail legitimately.
174 */
175 if (status)
176 pr_debug("%s: iso_complete status(%d) %d/%d\n",
177 __func__, status, req->actual, req->length);
178
179 substream = prm->ss;
180
181 /* Do nothing if ALSA isn't active */
182 if (!substream)
183 goto exit;
184
185 snd_pcm_stream_lock(substream);
186
187 runtime = substream->runtime;
188 if (!runtime || !snd_pcm_running(substream)) {
189 snd_pcm_stream_unlock(substream);
190 goto exit;
191 }
192
193 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
194 /*
195 * For each IN packet, take the quotient of the current data
196 * rate and the endpoint's interval as the base packet size.
197 * If there is a residue from this division, add it to the
198 * residue accumulator.
199 */
200 unsigned long long p_interval_mil = uac->p_interval * 1000000ULL;
201
202 pitched_rate_mil = (unsigned long long) prm->srate * prm->pitch;
203 div_result = pitched_rate_mil;
204 do_div(div_result, uac->p_interval);
205 do_div(div_result, 1000000);
206 frames = (unsigned int) div_result;
207
208 pr_debug("p_srate %d, pitch %d, interval_mil %llu, frames %d\n",
209 prm->srate, prm->pitch, p_interval_mil, frames);
210
211 p_pktsize = min_t(unsigned int,
212 uac->p_framesize * frames,
213 ep->maxpacket);
214
215 if (p_pktsize < ep->maxpacket) {
216 residue_frames_mil = pitched_rate_mil - frames * p_interval_mil;
217 p_pktsize_residue_mil = uac->p_framesize * residue_frames_mil;
218 } else
219 p_pktsize_residue_mil = 0;
220
221 req->length = p_pktsize;
222 uac->p_residue_mil += p_pktsize_residue_mil;
223
224 /*
225 * Whenever there are more bytes in the accumulator p_residue_mil than we
226 * need to add one more sample frame, increase this packet's
227 * size and decrease the accumulator.
228 */
229 div_result = uac->p_residue_mil;
230 do_div(div_result, uac->p_interval);
231 do_div(div_result, 1000000);
232 if ((unsigned int) div_result >= uac->p_framesize) {
233 req->length += uac->p_framesize;
234 uac->p_residue_mil -= uac->p_framesize * p_interval_mil;
235 pr_debug("increased req length to %d\n", req->length);
236 }
237 pr_debug("remains uac->p_residue_mil %llu\n", uac->p_residue_mil);
238
239 req->actual = req->length;
240 }
241
242 hw_ptr = prm->hw_ptr;
243
244 /* Pack USB load in ALSA ring buffer */
245 pending = runtime->dma_bytes - hw_ptr;
246
247 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
248 if (unlikely(pending < req->actual)) {
249 memcpy(req->buf, runtime->dma_area + hw_ptr, pending);
250 memcpy(req->buf + pending, runtime->dma_area,
251 req->actual - pending);
252 } else {
253 memcpy(req->buf, runtime->dma_area + hw_ptr,
254 req->actual);
255 }
256 } else {
257 if (unlikely(pending < req->actual)) {
258 memcpy(runtime->dma_area + hw_ptr, req->buf, pending);
259 memcpy(runtime->dma_area, req->buf + pending,
260 req->actual - pending);
261 } else {
262 memcpy(runtime->dma_area + hw_ptr, req->buf,
263 req->actual);
264 }
265 }
266
267 /* update hw_ptr after data is copied to memory */
268 prm->hw_ptr = (hw_ptr + req->actual) % runtime->dma_bytes;
269 hw_ptr = prm->hw_ptr;
270 snd_pcm_stream_unlock(substream);
271
272 if ((hw_ptr % snd_pcm_lib_period_bytes(substream)) < req->actual)
273 snd_pcm_period_elapsed(substream);
274
275exit:
276 if (usb_ep_queue(ep, req, GFP_ATOMIC))
277 dev_err(uac->card->dev, "%d Error!\n", __LINE__);
278}
279
280static void u_audio_iso_fback_complete(struct usb_ep *ep,
281 struct usb_request *req)
282{
283 struct uac_rtd_params *prm = req->context;
284 struct snd_uac_chip *uac = prm->uac;
285 struct g_audio *audio_dev = uac->audio_dev;
286 int status = req->status;
287
288 /* i/f shutting down */
289 if (!prm->fb_ep_enabled) {
290 kfree(req->buf);
291 usb_ep_free_request(ep, req);
292 return;
293 }
294
295 if (req->status == -ESHUTDOWN)
296 return;
297
298 /*
299 * We can't really do much about bad xfers.
300 * Afterall, the ISOCH xfers could fail legitimately.
301 */
302 if (status)
303 pr_debug("%s: iso_complete status(%d) %d/%d\n",
304 __func__, status, req->actual, req->length);
305
306 u_audio_set_fback_frequency(audio_dev->gadget->speed, audio_dev->out_ep,
307 prm->srate, prm->pitch,
308 req->buf);
309
310 if (usb_ep_queue(ep, req, GFP_ATOMIC))
311 dev_err(uac->card->dev, "%d Error!\n", __LINE__);
312}
313
314static int uac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
315{
316 struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
317 struct uac_rtd_params *prm;
318 struct g_audio *audio_dev;
319 struct uac_params *params;
320 int err = 0;
321
322 audio_dev = uac->audio_dev;
323 params = &audio_dev->params;
324
325 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
326 prm = &uac->p_prm;
327 else
328 prm = &uac->c_prm;
329
330 /* Reset */
331 prm->hw_ptr = 0;
332
333 switch (cmd) {
334 case SNDRV_PCM_TRIGGER_START:
335 case SNDRV_PCM_TRIGGER_RESUME:
336 prm->ss = substream;
337 break;
338 case SNDRV_PCM_TRIGGER_STOP:
339 case SNDRV_PCM_TRIGGER_SUSPEND:
340 prm->ss = NULL;
341 break;
342 default:
343 err = -EINVAL;
344 }
345
346 /* Clear buffer after Play stops */
347 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK && !prm->ss)
348 memset(prm->rbuf, 0, prm->max_psize * params->req_number);
349
350 return err;
351}
352
353static snd_pcm_uframes_t uac_pcm_pointer(struct snd_pcm_substream *substream)
354{
355 struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
356 struct uac_rtd_params *prm;
357
358 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
359 prm = &uac->p_prm;
360 else
361 prm = &uac->c_prm;
362
363 return bytes_to_frames(substream->runtime, prm->hw_ptr);
364}
365
366static u64 uac_ssize_to_fmt(int ssize)
367{
368 u64 ret;
369
370 switch (ssize) {
371 case 3:
372 ret = SNDRV_PCM_FMTBIT_S24_3LE;
373 break;
374 case 4:
375 ret = SNDRV_PCM_FMTBIT_S32_LE;
376 break;
377 default:
378 ret = SNDRV_PCM_FMTBIT_S16_LE;
379 break;
380 }
381
382 return ret;
383}
384
385static int uac_pcm_open(struct snd_pcm_substream *substream)
386{
387 struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
388 struct snd_pcm_runtime *runtime = substream->runtime;
389 struct g_audio *audio_dev;
390 struct uac_params *params;
391 struct uac_rtd_params *prm;
392 int p_ssize, c_ssize;
393 int p_chmask, c_chmask;
394
395 audio_dev = uac->audio_dev;
396 params = &audio_dev->params;
397 p_ssize = params->p_ssize;
398 c_ssize = params->c_ssize;
399 p_chmask = params->p_chmask;
400 c_chmask = params->c_chmask;
401 uac->p_residue_mil = 0;
402
403 runtime->hw = uac_pcm_hardware;
404
405 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
406 runtime->hw.formats = uac_ssize_to_fmt(p_ssize);
407 runtime->hw.channels_min = num_channels(p_chmask);
408 prm = &uac->p_prm;
409 } else {
410 runtime->hw.formats = uac_ssize_to_fmt(c_ssize);
411 runtime->hw.channels_min = num_channels(c_chmask);
412 prm = &uac->c_prm;
413 }
414
415 runtime->hw.period_bytes_min = 2 * prm->max_psize
416 / runtime->hw.periods_min;
417 runtime->hw.rate_min = prm->srate;
418 runtime->hw.rate_max = runtime->hw.rate_min;
419 runtime->hw.channels_max = runtime->hw.channels_min;
420
421 snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
422
423 return 0;
424}
425
426/* ALSA cries without these function pointers */
427static int uac_pcm_null(struct snd_pcm_substream *substream)
428{
429 return 0;
430}
431
432static const struct snd_pcm_ops uac_pcm_ops = {
433 .open = uac_pcm_open,
434 .close = uac_pcm_null,
435 .trigger = uac_pcm_trigger,
436 .pointer = uac_pcm_pointer,
437 .prepare = uac_pcm_null,
438};
439
440static inline void free_ep(struct uac_rtd_params *prm, struct usb_ep *ep)
441{
442 struct snd_uac_chip *uac = prm->uac;
443 struct g_audio *audio_dev;
444 struct uac_params *params;
445 int i;
446
447 if (!prm->ep_enabled)
448 return;
449
450 audio_dev = uac->audio_dev;
451 params = &audio_dev->params;
452
453 for (i = 0; i < params->req_number; i++) {
454 if (prm->reqs[i]) {
455 if (usb_ep_dequeue(ep, prm->reqs[i]))
456 usb_ep_free_request(ep, prm->reqs[i]);
457 /*
458 * If usb_ep_dequeue() cannot successfully dequeue the
459 * request, the request will be freed by the completion
460 * callback.
461 */
462
463 prm->reqs[i] = NULL;
464 }
465 }
466
467 prm->ep_enabled = false;
468
469 if (usb_ep_disable(ep))
470 dev_err(uac->card->dev, "%s:%d Error!\n", __func__, __LINE__);
471}
472
473static inline void free_ep_fback(struct uac_rtd_params *prm, struct usb_ep *ep)
474{
475 struct snd_uac_chip *uac = prm->uac;
476
477 if (!prm->fb_ep_enabled)
478 return;
479
480 if (prm->req_fback) {
481 if (usb_ep_dequeue(ep, prm->req_fback)) {
482 kfree(prm->req_fback->buf);
483 usb_ep_free_request(ep, prm->req_fback);
484 }
485 prm->req_fback = NULL;
486 }
487
488 prm->fb_ep_enabled = false;
489
490 if (usb_ep_disable(ep))
491 dev_err(uac->card->dev, "%s:%d Error!\n", __func__, __LINE__);
492}
493
494static void set_active(struct uac_rtd_params *prm, bool active)
495{
496 // notifying through the Rate ctrl
497 struct snd_kcontrol *kctl = prm->snd_kctl_rate;
498 unsigned long flags;
499
500 spin_lock_irqsave(&prm->lock, flags);
501 if (prm->active != active) {
502 prm->active = active;
503 snd_ctl_notify(prm->uac->card, SNDRV_CTL_EVENT_MASK_VALUE,
504 &kctl->id);
505 }
506 spin_unlock_irqrestore(&prm->lock, flags);
507}
508
509int u_audio_set_capture_srate(struct g_audio *audio_dev, int srate)
510{
511 struct uac_params *params = &audio_dev->params;
512 struct snd_uac_chip *uac = audio_dev->uac;
513 struct uac_rtd_params *prm;
514 int i;
515 unsigned long flags;
516
517 dev_dbg(&audio_dev->gadget->dev, "%s: srate %d\n", __func__, srate);
518 prm = &uac->c_prm;
519 for (i = 0; i < UAC_MAX_RATES; i++) {
520 if (params->c_srates[i] == srate) {
521 spin_lock_irqsave(&prm->lock, flags);
522 prm->srate = srate;
523 spin_unlock_irqrestore(&prm->lock, flags);
524 return 0;
525 }
526 if (params->c_srates[i] == 0)
527 break;
528 }
529
530 return -EINVAL;
531}
532EXPORT_SYMBOL_GPL(u_audio_set_capture_srate);
533
534int u_audio_get_capture_srate(struct g_audio *audio_dev, u32 *val)
535{
536 struct snd_uac_chip *uac = audio_dev->uac;
537 struct uac_rtd_params *prm;
538 unsigned long flags;
539
540 prm = &uac->c_prm;
541 spin_lock_irqsave(&prm->lock, flags);
542 *val = prm->srate;
543 spin_unlock_irqrestore(&prm->lock, flags);
544 return 0;
545}
546EXPORT_SYMBOL_GPL(u_audio_get_capture_srate);
547
548int u_audio_set_playback_srate(struct g_audio *audio_dev, int srate)
549{
550 struct uac_params *params = &audio_dev->params;
551 struct snd_uac_chip *uac = audio_dev->uac;
552 struct uac_rtd_params *prm;
553 int i;
554 unsigned long flags;
555
556 dev_dbg(&audio_dev->gadget->dev, "%s: srate %d\n", __func__, srate);
557 prm = &uac->p_prm;
558 for (i = 0; i < UAC_MAX_RATES; i++) {
559 if (params->p_srates[i] == srate) {
560 spin_lock_irqsave(&prm->lock, flags);
561 prm->srate = srate;
562 spin_unlock_irqrestore(&prm->lock, flags);
563 return 0;
564 }
565 if (params->p_srates[i] == 0)
566 break;
567 }
568
569 return -EINVAL;
570}
571EXPORT_SYMBOL_GPL(u_audio_set_playback_srate);
572
573int u_audio_get_playback_srate(struct g_audio *audio_dev, u32 *val)
574{
575 struct snd_uac_chip *uac = audio_dev->uac;
576 struct uac_rtd_params *prm;
577 unsigned long flags;
578
579 prm = &uac->p_prm;
580 spin_lock_irqsave(&prm->lock, flags);
581 *val = prm->srate;
582 spin_unlock_irqrestore(&prm->lock, flags);
583 return 0;
584}
585EXPORT_SYMBOL_GPL(u_audio_get_playback_srate);
586
587int u_audio_start_capture(struct g_audio *audio_dev)
588{
589 struct snd_uac_chip *uac = audio_dev->uac;
590 struct usb_gadget *gadget = audio_dev->gadget;
591 struct device *dev = &gadget->dev;
592 struct usb_request *req, *req_fback;
593 struct usb_ep *ep, *ep_fback;
594 struct uac_rtd_params *prm;
595 struct uac_params *params = &audio_dev->params;
596 int req_len, i;
597
598 prm = &uac->c_prm;
599 dev_dbg(dev, "start capture with rate %d\n", prm->srate);
600 ep = audio_dev->out_ep;
601 config_ep_by_speed(gadget, &audio_dev->func, ep);
602 req_len = ep->maxpacket;
603
604 prm->ep_enabled = true;
605 usb_ep_enable(ep);
606
607 for (i = 0; i < params->req_number; i++) {
608 if (!prm->reqs[i]) {
609 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
610 if (req == NULL)
611 return -ENOMEM;
612
613 prm->reqs[i] = req;
614
615 req->zero = 0;
616 req->context = prm;
617 req->length = req_len;
618 req->complete = u_audio_iso_complete;
619 req->buf = prm->rbuf + i * ep->maxpacket;
620 }
621
622 if (usb_ep_queue(ep, prm->reqs[i], GFP_ATOMIC))
623 dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
624 }
625
626 set_active(&uac->c_prm, true);
627
628 ep_fback = audio_dev->in_ep_fback;
629 if (!ep_fback)
630 return 0;
631
632 /* Setup feedback endpoint */
633 config_ep_by_speed(gadget, &audio_dev->func, ep_fback);
634 prm->fb_ep_enabled = true;
635 usb_ep_enable(ep_fback);
636 req_len = ep_fback->maxpacket;
637
638 req_fback = usb_ep_alloc_request(ep_fback, GFP_ATOMIC);
639 if (req_fback == NULL)
640 return -ENOMEM;
641
642 prm->req_fback = req_fback;
643 req_fback->zero = 0;
644 req_fback->context = prm;
645 req_fback->length = req_len;
646 req_fback->complete = u_audio_iso_fback_complete;
647
648 req_fback->buf = kzalloc(req_len, GFP_ATOMIC);
649 if (!req_fback->buf)
650 return -ENOMEM;
651
652 /*
653 * Configure the feedback endpoint's reported frequency.
654 * Always start with original frequency since its deviation can't
655 * be meauserd at start of playback
656 */
657 prm->pitch = 1000000;
658 u_audio_set_fback_frequency(audio_dev->gadget->speed, ep,
659 prm->srate, prm->pitch,
660 req_fback->buf);
661
662 if (usb_ep_queue(ep_fback, req_fback, GFP_ATOMIC))
663 dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
664
665 return 0;
666}
667EXPORT_SYMBOL_GPL(u_audio_start_capture);
668
669void u_audio_stop_capture(struct g_audio *audio_dev)
670{
671 struct snd_uac_chip *uac = audio_dev->uac;
672
673 set_active(&uac->c_prm, false);
674 if (audio_dev->in_ep_fback)
675 free_ep_fback(&uac->c_prm, audio_dev->in_ep_fback);
676 free_ep(&uac->c_prm, audio_dev->out_ep);
677}
678EXPORT_SYMBOL_GPL(u_audio_stop_capture);
679
680int u_audio_start_playback(struct g_audio *audio_dev)
681{
682 struct snd_uac_chip *uac = audio_dev->uac;
683 struct usb_gadget *gadget = audio_dev->gadget;
684 struct device *dev = &gadget->dev;
685 struct usb_request *req;
686 struct usb_ep *ep;
687 struct uac_rtd_params *prm;
688 struct uac_params *params = &audio_dev->params;
689 unsigned int factor;
690 const struct usb_endpoint_descriptor *ep_desc;
691 int req_len, i;
692 unsigned int p_pktsize;
693
694 prm = &uac->p_prm;
695 dev_dbg(dev, "start playback with rate %d\n", prm->srate);
696 ep = audio_dev->in_ep;
697 config_ep_by_speed(gadget, &audio_dev->func, ep);
698
699 ep_desc = ep->desc;
700 /*
701 * Always start with original frequency
702 */
703 prm->pitch = 1000000;
704
705 /* pre-calculate the playback endpoint's interval */
706 if (gadget->speed == USB_SPEED_FULL)
707 factor = 1000;
708 else
709 factor = 8000;
710
711 /* pre-compute some values for iso_complete() */
712 uac->p_framesize = params->p_ssize *
713 num_channels(params->p_chmask);
714 uac->p_interval = factor / (1 << (ep_desc->bInterval - 1));
715 p_pktsize = min_t(unsigned int,
716 uac->p_framesize *
717 (prm->srate / uac->p_interval),
718 ep->maxpacket);
719
720 req_len = p_pktsize;
721 uac->p_residue_mil = 0;
722
723 prm->ep_enabled = true;
724 usb_ep_enable(ep);
725
726 for (i = 0; i < params->req_number; i++) {
727 if (!prm->reqs[i]) {
728 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
729 if (req == NULL)
730 return -ENOMEM;
731
732 prm->reqs[i] = req;
733
734 req->zero = 0;
735 req->context = prm;
736 req->length = req_len;
737 req->complete = u_audio_iso_complete;
738 req->buf = prm->rbuf + i * ep->maxpacket;
739 }
740
741 if (usb_ep_queue(ep, prm->reqs[i], GFP_ATOMIC))
742 dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
743 }
744
745 set_active(&uac->p_prm, true);
746
747 return 0;
748}
749EXPORT_SYMBOL_GPL(u_audio_start_playback);
750
751void u_audio_stop_playback(struct g_audio *audio_dev)
752{
753 struct snd_uac_chip *uac = audio_dev->uac;
754
755 set_active(&uac->p_prm, false);
756 free_ep(&uac->p_prm, audio_dev->in_ep);
757}
758EXPORT_SYMBOL_GPL(u_audio_stop_playback);
759
760void u_audio_suspend(struct g_audio *audio_dev)
761{
762 struct snd_uac_chip *uac = audio_dev->uac;
763
764 set_active(&uac->p_prm, false);
765 set_active(&uac->c_prm, false);
766}
767EXPORT_SYMBOL_GPL(u_audio_suspend);
768
769int u_audio_get_volume(struct g_audio *audio_dev, int playback, s16 *val)
770{
771 struct snd_uac_chip *uac = audio_dev->uac;
772 struct uac_rtd_params *prm;
773 unsigned long flags;
774
775 if (playback)
776 prm = &uac->p_prm;
777 else
778 prm = &uac->c_prm;
779
780 spin_lock_irqsave(&prm->lock, flags);
781 *val = prm->volume;
782 spin_unlock_irqrestore(&prm->lock, flags);
783
784 return 0;
785}
786EXPORT_SYMBOL_GPL(u_audio_get_volume);
787
788int u_audio_set_volume(struct g_audio *audio_dev, int playback, s16 val)
789{
790 struct snd_uac_chip *uac = audio_dev->uac;
791 struct uac_rtd_params *prm;
792 unsigned long flags;
793 int change = 0;
794
795 if (playback)
796 prm = &uac->p_prm;
797 else
798 prm = &uac->c_prm;
799
800 spin_lock_irqsave(&prm->lock, flags);
801 val = clamp(val, prm->volume_min, prm->volume_max);
802 if (prm->volume != val) {
803 prm->volume = val;
804 change = 1;
805 }
806 spin_unlock_irqrestore(&prm->lock, flags);
807
808 if (change)
809 snd_ctl_notify(uac->card, SNDRV_CTL_EVENT_MASK_VALUE,
810 &prm->snd_kctl_volume->id);
811
812 return 0;
813}
814EXPORT_SYMBOL_GPL(u_audio_set_volume);
815
816int u_audio_get_mute(struct g_audio *audio_dev, int playback, int *val)
817{
818 struct snd_uac_chip *uac = audio_dev->uac;
819 struct uac_rtd_params *prm;
820 unsigned long flags;
821
822 if (playback)
823 prm = &uac->p_prm;
824 else
825 prm = &uac->c_prm;
826
827 spin_lock_irqsave(&prm->lock, flags);
828 *val = prm->mute;
829 spin_unlock_irqrestore(&prm->lock, flags);
830
831 return 0;
832}
833EXPORT_SYMBOL_GPL(u_audio_get_mute);
834
835int u_audio_set_mute(struct g_audio *audio_dev, int playback, int val)
836{
837 struct snd_uac_chip *uac = audio_dev->uac;
838 struct uac_rtd_params *prm;
839 unsigned long flags;
840 int change = 0;
841 int mute;
842
843 if (playback)
844 prm = &uac->p_prm;
845 else
846 prm = &uac->c_prm;
847
848 mute = val ? 1 : 0;
849
850 spin_lock_irqsave(&prm->lock, flags);
851 if (prm->mute != mute) {
852 prm->mute = mute;
853 change = 1;
854 }
855 spin_unlock_irqrestore(&prm->lock, flags);
856
857 if (change)
858 snd_ctl_notify(uac->card, SNDRV_CTL_EVENT_MASK_VALUE,
859 &prm->snd_kctl_mute->id);
860
861 return 0;
862}
863EXPORT_SYMBOL_GPL(u_audio_set_mute);
864
865
866static int u_audio_pitch_info(struct snd_kcontrol *kcontrol,
867 struct snd_ctl_elem_info *uinfo)
868{
869 struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
870 struct snd_uac_chip *uac = prm->uac;
871 struct g_audio *audio_dev = uac->audio_dev;
872 struct uac_params *params = &audio_dev->params;
873 unsigned int pitch_min, pitch_max;
874
875 pitch_min = (1000 - FBACK_SLOW_MAX) * 1000;
876 pitch_max = (1000 + params->fb_max) * 1000;
877
878 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
879 uinfo->count = 1;
880 uinfo->value.integer.min = pitch_min;
881 uinfo->value.integer.max = pitch_max;
882 uinfo->value.integer.step = 1;
883 return 0;
884}
885
886static int u_audio_pitch_get(struct snd_kcontrol *kcontrol,
887 struct snd_ctl_elem_value *ucontrol)
888{
889 struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
890
891 ucontrol->value.integer.value[0] = prm->pitch;
892
893 return 0;
894}
895
896static int u_audio_pitch_put(struct snd_kcontrol *kcontrol,
897 struct snd_ctl_elem_value *ucontrol)
898{
899 struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
900 struct snd_uac_chip *uac = prm->uac;
901 struct g_audio *audio_dev = uac->audio_dev;
902 struct uac_params *params = &audio_dev->params;
903 unsigned int val;
904 unsigned int pitch_min, pitch_max;
905 int change = 0;
906
907 pitch_min = (1000 - FBACK_SLOW_MAX) * 1000;
908 pitch_max = (1000 + params->fb_max) * 1000;
909
910 val = ucontrol->value.integer.value[0];
911
912 if (val < pitch_min)
913 val = pitch_min;
914 if (val > pitch_max)
915 val = pitch_max;
916
917 if (prm->pitch != val) {
918 prm->pitch = val;
919 change = 1;
920 }
921
922 return change;
923}
924
925static int u_audio_mute_info(struct snd_kcontrol *kcontrol,
926 struct snd_ctl_elem_info *uinfo)
927{
928 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
929 uinfo->count = 1;
930 uinfo->value.integer.min = 0;
931 uinfo->value.integer.max = 1;
932 uinfo->value.integer.step = 1;
933
934 return 0;
935}
936
937static int u_audio_mute_get(struct snd_kcontrol *kcontrol,
938 struct snd_ctl_elem_value *ucontrol)
939{
940 struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
941 unsigned long flags;
942
943 spin_lock_irqsave(&prm->lock, flags);
944 ucontrol->value.integer.value[0] = !prm->mute;
945 spin_unlock_irqrestore(&prm->lock, flags);
946
947 return 0;
948}
949
950static int u_audio_mute_put(struct snd_kcontrol *kcontrol,
951 struct snd_ctl_elem_value *ucontrol)
952{
953 struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
954 struct snd_uac_chip *uac = prm->uac;
955 struct g_audio *audio_dev = uac->audio_dev;
956 unsigned int val;
957 unsigned long flags;
958 int change = 0;
959
960 val = !ucontrol->value.integer.value[0];
961
962 spin_lock_irqsave(&prm->lock, flags);
963 if (val != prm->mute) {
964 prm->mute = val;
965 change = 1;
966 }
967 spin_unlock_irqrestore(&prm->lock, flags);
968
969 if (change && audio_dev->notify)
970 audio_dev->notify(audio_dev, prm->fu_id, UAC_FU_MUTE);
971
972 return change;
973}
974
975/*
976 * TLV callback for mixer volume controls
977 */
978static int u_audio_volume_tlv(struct snd_kcontrol *kcontrol, int op_flag,
979 unsigned int size, unsigned int __user *_tlv)
980{
981 struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
982 DECLARE_TLV_DB_MINMAX(scale, 0, 0);
983
984 if (size < sizeof(scale))
985 return -ENOMEM;
986
987 /* UAC volume resolution is 1/256 dB, TLV is 1/100 dB */
988 scale[2] = (prm->volume_min * 100) / 256;
989 scale[3] = (prm->volume_max * 100) / 256;
990 if (copy_to_user(_tlv, scale, sizeof(scale)))
991 return -EFAULT;
992
993 return 0;
994}
995
996static int u_audio_volume_info(struct snd_kcontrol *kcontrol,
997 struct snd_ctl_elem_info *uinfo)
998{
999 struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
1000
1001 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1002 uinfo->count = 1;
1003 uinfo->value.integer.min = 0;
1004 uinfo->value.integer.max =
1005 (prm->volume_max - prm->volume_min + prm->volume_res - 1)
1006 / prm->volume_res;
1007 uinfo->value.integer.step = 1;
1008
1009 return 0;
1010}
1011
1012static int u_audio_volume_get(struct snd_kcontrol *kcontrol,
1013 struct snd_ctl_elem_value *ucontrol)
1014{
1015 struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
1016 unsigned long flags;
1017
1018 spin_lock_irqsave(&prm->lock, flags);
1019 ucontrol->value.integer.value[0] =
1020 (prm->volume - prm->volume_min) / prm->volume_res;
1021 spin_unlock_irqrestore(&prm->lock, flags);
1022
1023 return 0;
1024}
1025
1026static int u_audio_volume_put(struct snd_kcontrol *kcontrol,
1027 struct snd_ctl_elem_value *ucontrol)
1028{
1029 struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
1030 struct snd_uac_chip *uac = prm->uac;
1031 struct g_audio *audio_dev = uac->audio_dev;
1032 unsigned int val;
1033 s16 volume;
1034 unsigned long flags;
1035 int change = 0;
1036
1037 val = ucontrol->value.integer.value[0];
1038
1039 spin_lock_irqsave(&prm->lock, flags);
1040 volume = (val * prm->volume_res) + prm->volume_min;
1041 volume = clamp(volume, prm->volume_min, prm->volume_max);
1042 if (volume != prm->volume) {
1043 prm->volume = volume;
1044 change = 1;
1045 }
1046 spin_unlock_irqrestore(&prm->lock, flags);
1047
1048 if (change && audio_dev->notify)
1049 audio_dev->notify(audio_dev, prm->fu_id, UAC_FU_VOLUME);
1050
1051 return change;
1052}
1053
1054static int get_max_srate(const int *srates)
1055{
1056 int i, max_srate = 0;
1057
1058 for (i = 0; i < UAC_MAX_RATES; i++) {
1059 if (srates[i] == 0)
1060 break;
1061 if (srates[i] > max_srate)
1062 max_srate = srates[i];
1063 }
1064 return max_srate;
1065}
1066
1067static int get_min_srate(const int *srates)
1068{
1069 int i, min_srate = INT_MAX;
1070
1071 for (i = 0; i < UAC_MAX_RATES; i++) {
1072 if (srates[i] == 0)
1073 break;
1074 if (srates[i] < min_srate)
1075 min_srate = srates[i];
1076 }
1077 return min_srate;
1078}
1079
1080static int u_audio_rate_info(struct snd_kcontrol *kcontrol,
1081 struct snd_ctl_elem_info *uinfo)
1082{
1083 const int *srates;
1084 struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
1085 struct snd_uac_chip *uac = prm->uac;
1086 struct g_audio *audio_dev = uac->audio_dev;
1087 struct uac_params *params = &audio_dev->params;
1088
1089 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1090 uinfo->count = 1;
1091
1092 if (prm == &uac->c_prm)
1093 srates = params->c_srates;
1094 else
1095 srates = params->p_srates;
1096 uinfo->value.integer.min = get_min_srate(srates);
1097 uinfo->value.integer.max = get_max_srate(srates);
1098 return 0;
1099}
1100
1101static int u_audio_rate_get(struct snd_kcontrol *kcontrol,
1102 struct snd_ctl_elem_value *ucontrol)
1103{
1104 struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
1105 unsigned long flags;
1106
1107 spin_lock_irqsave(&prm->lock, flags);
1108 if (prm->active)
1109 ucontrol->value.integer.value[0] = prm->srate;
1110 else
1111 /* not active: reporting zero rate */
1112 ucontrol->value.integer.value[0] = 0;
1113 spin_unlock_irqrestore(&prm->lock, flags);
1114 return 0;
1115}
1116
1117static struct snd_kcontrol_new u_audio_controls[] = {
1118 [UAC_FBACK_CTRL] {
1119 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
1120 .name = "Capture Pitch 1000000",
1121 .info = u_audio_pitch_info,
1122 .get = u_audio_pitch_get,
1123 .put = u_audio_pitch_put,
1124 },
1125 [UAC_P_PITCH_CTRL] {
1126 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
1127 .name = "Playback Pitch 1000000",
1128 .info = u_audio_pitch_info,
1129 .get = u_audio_pitch_get,
1130 .put = u_audio_pitch_put,
1131 },
1132 [UAC_MUTE_CTRL] {
1133 .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1134 .name = "", /* will be filled later */
1135 .info = u_audio_mute_info,
1136 .get = u_audio_mute_get,
1137 .put = u_audio_mute_put,
1138 },
1139 [UAC_VOLUME_CTRL] {
1140 .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1141 .name = "", /* will be filled later */
1142 .info = u_audio_volume_info,
1143 .get = u_audio_volume_get,
1144 .put = u_audio_volume_put,
1145 },
1146 [UAC_RATE_CTRL] {
1147 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
1148 .name = "", /* will be filled later */
1149 .access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
1150 .info = u_audio_rate_info,
1151 .get = u_audio_rate_get,
1152 },
1153};
1154
1155int g_audio_setup(struct g_audio *g_audio, const char *pcm_name,
1156 const char *card_name)
1157{
1158 struct snd_uac_chip *uac;
1159 struct snd_card *card;
1160 struct snd_pcm *pcm;
1161 struct snd_kcontrol *kctl;
1162 struct uac_params *params;
1163 int p_chmask, c_chmask;
1164 int i, err;
1165
1166 if (!g_audio)
1167 return -EINVAL;
1168
1169 uac = kzalloc(sizeof(*uac), GFP_KERNEL);
1170 if (!uac)
1171 return -ENOMEM;
1172 g_audio->uac = uac;
1173 uac->audio_dev = g_audio;
1174
1175 params = &g_audio->params;
1176 p_chmask = params->p_chmask;
1177 c_chmask = params->c_chmask;
1178
1179 if (c_chmask) {
1180 struct uac_rtd_params *prm = &uac->c_prm;
1181
1182 spin_lock_init(&prm->lock);
1183 uac->c_prm.uac = uac;
1184 prm->max_psize = g_audio->out_ep_maxpsize;
1185 prm->srate = params->c_srates[0];
1186
1187 prm->reqs = kcalloc(params->req_number,
1188 sizeof(struct usb_request *),
1189 GFP_KERNEL);
1190 if (!prm->reqs) {
1191 err = -ENOMEM;
1192 goto fail;
1193 }
1194
1195 prm->rbuf = kcalloc(params->req_number, prm->max_psize,
1196 GFP_KERNEL);
1197 if (!prm->rbuf) {
1198 prm->max_psize = 0;
1199 err = -ENOMEM;
1200 goto fail;
1201 }
1202 }
1203
1204 if (p_chmask) {
1205 struct uac_rtd_params *prm = &uac->p_prm;
1206
1207 spin_lock_init(&prm->lock);
1208 uac->p_prm.uac = uac;
1209 prm->max_psize = g_audio->in_ep_maxpsize;
1210 prm->srate = params->p_srates[0];
1211
1212 prm->reqs = kcalloc(params->req_number,
1213 sizeof(struct usb_request *),
1214 GFP_KERNEL);
1215 if (!prm->reqs) {
1216 err = -ENOMEM;
1217 goto fail;
1218 }
1219
1220 prm->rbuf = kcalloc(params->req_number, prm->max_psize,
1221 GFP_KERNEL);
1222 if (!prm->rbuf) {
1223 prm->max_psize = 0;
1224 err = -ENOMEM;
1225 goto fail;
1226 }
1227 }
1228
1229 /* Choose any slot, with no id */
1230 err = snd_card_new(&g_audio->gadget->dev,
1231 -1, NULL, THIS_MODULE, 0, &card);
1232 if (err < 0)
1233 goto fail;
1234
1235 uac->card = card;
1236
1237 /*
1238 * Create first PCM device
1239 * Create a substream only for non-zero channel streams
1240 */
1241 err = snd_pcm_new(uac->card, pcm_name, 0,
1242 p_chmask ? 1 : 0, c_chmask ? 1 : 0, &pcm);
1243 if (err < 0)
1244 goto snd_fail;
1245
1246 strscpy(pcm->name, pcm_name, sizeof(pcm->name));
1247 pcm->private_data = uac;
1248 uac->pcm = pcm;
1249
1250 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &uac_pcm_ops);
1251 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &uac_pcm_ops);
1252
1253 /*
1254 * Create mixer and controls
1255 * Create only if it's required on USB side
1256 */
1257 if ((c_chmask && g_audio->in_ep_fback)
1258 || (p_chmask && params->p_fu.id)
1259 || (c_chmask && params->c_fu.id))
1260 strscpy(card->mixername, card_name, sizeof(card->driver));
1261
1262 if (c_chmask && g_audio->in_ep_fback) {
1263 kctl = snd_ctl_new1(&u_audio_controls[UAC_FBACK_CTRL],
1264 &uac->c_prm);
1265 if (!kctl) {
1266 err = -ENOMEM;
1267 goto snd_fail;
1268 }
1269
1270 kctl->id.device = pcm->device;
1271 kctl->id.subdevice = 0;
1272
1273 err = snd_ctl_add(card, kctl);
1274 if (err < 0)
1275 goto snd_fail;
1276 }
1277
1278 if (p_chmask) {
1279 kctl = snd_ctl_new1(&u_audio_controls[UAC_P_PITCH_CTRL],
1280 &uac->p_prm);
1281 if (!kctl) {
1282 err = -ENOMEM;
1283 goto snd_fail;
1284 }
1285
1286 kctl->id.device = pcm->device;
1287 kctl->id.subdevice = 0;
1288
1289 err = snd_ctl_add(card, kctl);
1290 if (err < 0)
1291 goto snd_fail;
1292 }
1293
1294 for (i = 0; i <= SNDRV_PCM_STREAM_LAST; i++) {
1295 struct uac_rtd_params *prm;
1296 struct uac_fu_params *fu;
1297 char ctrl_name[24];
1298 char *direction;
1299
1300 if (!pcm->streams[i].substream_count)
1301 continue;
1302
1303 if (i == SNDRV_PCM_STREAM_PLAYBACK) {
1304 prm = &uac->p_prm;
1305 fu = ¶ms->p_fu;
1306 direction = "Playback";
1307 } else {
1308 prm = &uac->c_prm;
1309 fu = ¶ms->c_fu;
1310 direction = "Capture";
1311 }
1312
1313 prm->fu_id = fu->id;
1314
1315 if (fu->mute_present) {
1316 snprintf(ctrl_name, sizeof(ctrl_name),
1317 "PCM %s Switch", direction);
1318
1319 u_audio_controls[UAC_MUTE_CTRL].name = ctrl_name;
1320
1321 kctl = snd_ctl_new1(&u_audio_controls[UAC_MUTE_CTRL],
1322 prm);
1323 if (!kctl) {
1324 err = -ENOMEM;
1325 goto snd_fail;
1326 }
1327
1328 kctl->id.device = pcm->device;
1329 kctl->id.subdevice = 0;
1330
1331 err = snd_ctl_add(card, kctl);
1332 if (err < 0)
1333 goto snd_fail;
1334 prm->snd_kctl_mute = kctl;
1335 prm->mute = 0;
1336 }
1337
1338 if (fu->volume_present) {
1339 snprintf(ctrl_name, sizeof(ctrl_name),
1340 "PCM %s Volume", direction);
1341
1342 u_audio_controls[UAC_VOLUME_CTRL].name = ctrl_name;
1343
1344 kctl = snd_ctl_new1(&u_audio_controls[UAC_VOLUME_CTRL],
1345 prm);
1346 if (!kctl) {
1347 err = -ENOMEM;
1348 goto snd_fail;
1349 }
1350
1351 kctl->id.device = pcm->device;
1352 kctl->id.subdevice = 0;
1353
1354
1355 kctl->tlv.c = u_audio_volume_tlv;
1356 kctl->vd[0].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1357 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1358
1359 err = snd_ctl_add(card, kctl);
1360 if (err < 0)
1361 goto snd_fail;
1362 prm->snd_kctl_volume = kctl;
1363 prm->volume = fu->volume_max;
1364 prm->volume_max = fu->volume_max;
1365 prm->volume_min = fu->volume_min;
1366 prm->volume_res = fu->volume_res;
1367 }
1368
1369 /* Add rate control */
1370 snprintf(ctrl_name, sizeof(ctrl_name),
1371 "%s Rate", direction);
1372 u_audio_controls[UAC_RATE_CTRL].name = ctrl_name;
1373
1374 kctl = snd_ctl_new1(&u_audio_controls[UAC_RATE_CTRL], prm);
1375 if (!kctl) {
1376 err = -ENOMEM;
1377 goto snd_fail;
1378 }
1379
1380 kctl->id.device = pcm->device;
1381 kctl->id.subdevice = 0;
1382
1383 err = snd_ctl_add(card, kctl);
1384 if (err < 0)
1385 goto snd_fail;
1386 prm->snd_kctl_rate = kctl;
1387 }
1388
1389 strscpy(card->driver, card_name, sizeof(card->driver));
1390 strscpy(card->shortname, card_name, sizeof(card->shortname));
1391 sprintf(card->longname, "%s %i", card_name, card->dev->id);
1392
1393 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
1394 NULL, 0, BUFF_SIZE_MAX);
1395
1396 err = snd_card_register(card);
1397
1398 if (!err)
1399 return 0;
1400
1401snd_fail:
1402 snd_card_free(card);
1403fail:
1404 kfree(uac->p_prm.reqs);
1405 kfree(uac->c_prm.reqs);
1406 kfree(uac->p_prm.rbuf);
1407 kfree(uac->c_prm.rbuf);
1408 kfree(uac);
1409
1410 return err;
1411}
1412EXPORT_SYMBOL_GPL(g_audio_setup);
1413
1414void g_audio_cleanup(struct g_audio *g_audio)
1415{
1416 struct snd_uac_chip *uac;
1417 struct snd_card *card;
1418
1419 if (!g_audio || !g_audio->uac)
1420 return;
1421
1422 uac = g_audio->uac;
1423 card = uac->card;
1424 if (card)
1425 snd_card_free_when_closed(card);
1426
1427 kfree(uac->p_prm.reqs);
1428 kfree(uac->c_prm.reqs);
1429 kfree(uac->p_prm.rbuf);
1430 kfree(uac->c_prm.rbuf);
1431 kfree(uac);
1432}
1433EXPORT_SYMBOL_GPL(g_audio_cleanup);
1434
1435MODULE_LICENSE("GPL");
1436MODULE_DESCRIPTION("USB gadget \"ALSA sound card\" utilities");
1437MODULE_AUTHOR("Ruslan Bilovol");