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15#include <linux/module.h>
16#include <sound/core.h>
17#include <sound/pcm.h>
18#include <sound/pcm_params.h>
19
20#include "u_audio.h"
21
22#define BUFF_SIZE_MAX (PAGE_SIZE * 16)
23#define PRD_SIZE_MAX PAGE_SIZE
24#define MIN_PERIODS 4
25
26struct uac_req {
27 struct uac_rtd_params *pp;
28 struct usb_request *req;
29};
30
31
32struct uac_rtd_params {
33 struct snd_uac_chip *uac;
34 bool ep_enabled;
35
36 struct snd_pcm_substream *ss;
37
38
39 ssize_t hw_ptr;
40
41 void *rbuf;
42
43 unsigned int max_psize;
44 struct uac_req *ureq;
45
46 spinlock_t lock;
47};
48
49struct snd_uac_chip {
50 struct g_audio *audio_dev;
51
52 struct uac_rtd_params p_prm;
53 struct uac_rtd_params c_prm;
54
55 struct snd_card *card;
56 struct snd_pcm *pcm;
57
58
59 unsigned int p_interval;
60 unsigned int p_residue;
61
62
63 unsigned int p_pktsize;
64 unsigned int p_pktsize_residue;
65 unsigned int p_framesize;
66};
67
68static const struct snd_pcm_hardware uac_pcm_hardware = {
69 .info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER
70 | SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID
71 | SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME,
72 .rates = SNDRV_PCM_RATE_CONTINUOUS,
73 .periods_max = BUFF_SIZE_MAX / PRD_SIZE_MAX,
74 .buffer_bytes_max = BUFF_SIZE_MAX,
75 .period_bytes_max = PRD_SIZE_MAX,
76 .periods_min = MIN_PERIODS,
77};
78
79static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
80{
81 unsigned int pending;
82 unsigned long flags, flags2;
83 unsigned int hw_ptr;
84 int status = req->status;
85 struct uac_req *ur = req->context;
86 struct snd_pcm_substream *substream;
87 struct snd_pcm_runtime *runtime;
88 struct uac_rtd_params *prm = ur->pp;
89 struct snd_uac_chip *uac = prm->uac;
90
91
92 if (!prm->ep_enabled || req->status == -ESHUTDOWN)
93 return;
94
95
96
97
98
99 if (status)
100 pr_debug("%s: iso_complete status(%d) %d/%d\n",
101 __func__, status, req->actual, req->length);
102
103 substream = prm->ss;
104
105
106 if (!substream)
107 goto exit;
108
109 snd_pcm_stream_lock_irqsave(substream, flags2);
110
111 runtime = substream->runtime;
112 if (!runtime || !snd_pcm_running(substream)) {
113 snd_pcm_stream_unlock_irqrestore(substream, flags2);
114 goto exit;
115 }
116
117 spin_lock_irqsave(&prm->lock, flags);
118
119 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
120
121
122
123
124
125
126 req->length = uac->p_pktsize;
127 uac->p_residue += uac->p_pktsize_residue;
128
129
130
131
132
133
134 if (uac->p_residue / uac->p_interval >= uac->p_framesize) {
135 req->length += uac->p_framesize;
136 uac->p_residue -= uac->p_framesize *
137 uac->p_interval;
138 }
139
140 req->actual = req->length;
141 }
142
143 hw_ptr = prm->hw_ptr;
144
145 spin_unlock_irqrestore(&prm->lock, flags);
146
147
148 pending = runtime->dma_bytes - hw_ptr;
149
150 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
151 if (unlikely(pending < req->actual)) {
152 memcpy(req->buf, runtime->dma_area + hw_ptr, pending);
153 memcpy(req->buf + pending, runtime->dma_area,
154 req->actual - pending);
155 } else {
156 memcpy(req->buf, runtime->dma_area + hw_ptr,
157 req->actual);
158 }
159 } else {
160 if (unlikely(pending < req->actual)) {
161 memcpy(runtime->dma_area + hw_ptr, req->buf, pending);
162 memcpy(runtime->dma_area, req->buf + pending,
163 req->actual - pending);
164 } else {
165 memcpy(runtime->dma_area + hw_ptr, req->buf,
166 req->actual);
167 }
168 }
169
170 spin_lock_irqsave(&prm->lock, flags);
171
172 prm->hw_ptr = (hw_ptr + req->actual) % runtime->dma_bytes;
173 hw_ptr = prm->hw_ptr;
174 spin_unlock_irqrestore(&prm->lock, flags);
175 snd_pcm_stream_unlock_irqrestore(substream, flags2);
176
177 if ((hw_ptr % snd_pcm_lib_period_bytes(substream)) < req->actual)
178 snd_pcm_period_elapsed(substream);
179
180exit:
181 if (usb_ep_queue(ep, req, GFP_ATOMIC))
182 dev_err(uac->card->dev, "%d Error!\n", __LINE__);
183}
184
185static int uac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
186{
187 struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
188 struct uac_rtd_params *prm;
189 struct g_audio *audio_dev;
190 struct uac_params *params;
191 unsigned long flags;
192 int err = 0;
193
194 audio_dev = uac->audio_dev;
195 params = &audio_dev->params;
196
197 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
198 prm = &uac->p_prm;
199 else
200 prm = &uac->c_prm;
201
202 spin_lock_irqsave(&prm->lock, flags);
203
204
205 prm->hw_ptr = 0;
206
207 switch (cmd) {
208 case SNDRV_PCM_TRIGGER_START:
209 case SNDRV_PCM_TRIGGER_RESUME:
210 prm->ss = substream;
211 break;
212 case SNDRV_PCM_TRIGGER_STOP:
213 case SNDRV_PCM_TRIGGER_SUSPEND:
214 prm->ss = NULL;
215 break;
216 default:
217 err = -EINVAL;
218 }
219
220 spin_unlock_irqrestore(&prm->lock, flags);
221
222
223 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK && !prm->ss)
224 memset(prm->rbuf, 0, prm->max_psize * params->req_number);
225
226 return err;
227}
228
229static snd_pcm_uframes_t uac_pcm_pointer(struct snd_pcm_substream *substream)
230{
231 struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
232 struct uac_rtd_params *prm;
233
234 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
235 prm = &uac->p_prm;
236 else
237 prm = &uac->c_prm;
238
239 return bytes_to_frames(substream->runtime, prm->hw_ptr);
240}
241
242static int uac_pcm_open(struct snd_pcm_substream *substream)
243{
244 struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
245 struct snd_pcm_runtime *runtime = substream->runtime;
246 struct g_audio *audio_dev;
247 struct uac_params *params;
248 int p_ssize, c_ssize;
249 int p_srate, c_srate;
250 int p_chmask, c_chmask;
251
252 audio_dev = uac->audio_dev;
253 params = &audio_dev->params;
254 p_ssize = params->p_ssize;
255 c_ssize = params->c_ssize;
256 p_srate = params->p_srate;
257 c_srate = params->c_srate;
258 p_chmask = params->p_chmask;
259 c_chmask = params->c_chmask;
260 uac->p_residue = 0;
261
262 runtime->hw = uac_pcm_hardware;
263
264 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
265 spin_lock_init(&uac->p_prm.lock);
266 runtime->hw.rate_min = p_srate;
267 switch (p_ssize) {
268 case 3:
269 runtime->hw.formats = SNDRV_PCM_FMTBIT_S24_3LE;
270 break;
271 case 4:
272 runtime->hw.formats = SNDRV_PCM_FMTBIT_S32_LE;
273 break;
274 default:
275 runtime->hw.formats = SNDRV_PCM_FMTBIT_S16_LE;
276 break;
277 }
278 runtime->hw.channels_min = num_channels(p_chmask);
279 runtime->hw.period_bytes_min = 2 * uac->p_prm.max_psize
280 / runtime->hw.periods_min;
281 } else {
282 spin_lock_init(&uac->c_prm.lock);
283 runtime->hw.rate_min = c_srate;
284 switch (c_ssize) {
285 case 3:
286 runtime->hw.formats = SNDRV_PCM_FMTBIT_S24_3LE;
287 break;
288 case 4:
289 runtime->hw.formats = SNDRV_PCM_FMTBIT_S32_LE;
290 break;
291 default:
292 runtime->hw.formats = SNDRV_PCM_FMTBIT_S16_LE;
293 break;
294 }
295 runtime->hw.channels_min = num_channels(c_chmask);
296 runtime->hw.period_bytes_min = 2 * uac->c_prm.max_psize
297 / runtime->hw.periods_min;
298 }
299
300 runtime->hw.rate_max = runtime->hw.rate_min;
301 runtime->hw.channels_max = runtime->hw.channels_min;
302
303 snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
304
305 return 0;
306}
307
308
309static int uac_pcm_null(struct snd_pcm_substream *substream)
310{
311 return 0;
312}
313
314static const struct snd_pcm_ops uac_pcm_ops = {
315 .open = uac_pcm_open,
316 .close = uac_pcm_null,
317 .trigger = uac_pcm_trigger,
318 .pointer = uac_pcm_pointer,
319 .prepare = uac_pcm_null,
320};
321
322static inline void free_ep(struct uac_rtd_params *prm, struct usb_ep *ep)
323{
324 struct snd_uac_chip *uac = prm->uac;
325 struct g_audio *audio_dev;
326 struct uac_params *params;
327 int i;
328
329 if (!prm->ep_enabled)
330 return;
331
332 prm->ep_enabled = false;
333
334 audio_dev = uac->audio_dev;
335 params = &audio_dev->params;
336
337 for (i = 0; i < params->req_number; i++) {
338 if (prm->ureq[i].req) {
339 usb_ep_dequeue(ep, prm->ureq[i].req);
340 usb_ep_free_request(ep, prm->ureq[i].req);
341 prm->ureq[i].req = NULL;
342 }
343 }
344
345 if (usb_ep_disable(ep))
346 dev_err(uac->card->dev, "%s:%d Error!\n", __func__, __LINE__);
347}
348
349
350int u_audio_start_capture(struct g_audio *audio_dev)
351{
352 struct snd_uac_chip *uac = audio_dev->uac;
353 struct usb_gadget *gadget = audio_dev->gadget;
354 struct device *dev = &gadget->dev;
355 struct usb_request *req;
356 struct usb_ep *ep;
357 struct uac_rtd_params *prm;
358 struct uac_params *params = &audio_dev->params;
359 int req_len, i;
360
361 ep = audio_dev->out_ep;
362 prm = &uac->c_prm;
363 config_ep_by_speed(gadget, &audio_dev->func, ep);
364 req_len = ep->maxpacket;
365
366 prm->ep_enabled = true;
367 usb_ep_enable(ep);
368
369 for (i = 0; i < params->req_number; i++) {
370 if (!prm->ureq[i].req) {
371 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
372 if (req == NULL)
373 return -ENOMEM;
374
375 prm->ureq[i].req = req;
376 prm->ureq[i].pp = prm;
377
378 req->zero = 0;
379 req->context = &prm->ureq[i];
380 req->length = req_len;
381 req->complete = u_audio_iso_complete;
382 req->buf = prm->rbuf + i * ep->maxpacket;
383 }
384
385 if (usb_ep_queue(ep, prm->ureq[i].req, GFP_ATOMIC))
386 dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
387 }
388
389 return 0;
390}
391EXPORT_SYMBOL_GPL(u_audio_start_capture);
392
393void u_audio_stop_capture(struct g_audio *audio_dev)
394{
395 struct snd_uac_chip *uac = audio_dev->uac;
396
397 free_ep(&uac->c_prm, audio_dev->out_ep);
398}
399EXPORT_SYMBOL_GPL(u_audio_stop_capture);
400
401int u_audio_start_playback(struct g_audio *audio_dev)
402{
403 struct snd_uac_chip *uac = audio_dev->uac;
404 struct usb_gadget *gadget = audio_dev->gadget;
405 struct device *dev = &gadget->dev;
406 struct usb_request *req;
407 struct usb_ep *ep;
408 struct uac_rtd_params *prm;
409 struct uac_params *params = &audio_dev->params;
410 unsigned int factor;
411 const struct usb_endpoint_descriptor *ep_desc;
412 int req_len, i;
413
414 ep = audio_dev->in_ep;
415 prm = &uac->p_prm;
416 config_ep_by_speed(gadget, &audio_dev->func, ep);
417
418 ep_desc = ep->desc;
419
420
421 if (gadget->speed == USB_SPEED_FULL)
422 factor = 1000;
423 else
424 factor = 8000;
425
426
427 uac->p_framesize = params->p_ssize *
428 num_channels(params->p_chmask);
429 uac->p_interval = factor / (1 << (ep_desc->bInterval - 1));
430 uac->p_pktsize = min_t(unsigned int,
431 uac->p_framesize *
432 (params->p_srate / uac->p_interval),
433 ep->maxpacket);
434
435 if (uac->p_pktsize < ep->maxpacket)
436 uac->p_pktsize_residue = uac->p_framesize *
437 (params->p_srate % uac->p_interval);
438 else
439 uac->p_pktsize_residue = 0;
440
441 req_len = uac->p_pktsize;
442 uac->p_residue = 0;
443
444 prm->ep_enabled = true;
445 usb_ep_enable(ep);
446
447 for (i = 0; i < params->req_number; i++) {
448 if (!prm->ureq[i].req) {
449 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
450 if (req == NULL)
451 return -ENOMEM;
452
453 prm->ureq[i].req = req;
454 prm->ureq[i].pp = prm;
455
456 req->zero = 0;
457 req->context = &prm->ureq[i];
458 req->length = req_len;
459 req->complete = u_audio_iso_complete;
460 req->buf = prm->rbuf + i * ep->maxpacket;
461 }
462
463 if (usb_ep_queue(ep, prm->ureq[i].req, GFP_ATOMIC))
464 dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
465 }
466
467 return 0;
468}
469EXPORT_SYMBOL_GPL(u_audio_start_playback);
470
471void u_audio_stop_playback(struct g_audio *audio_dev)
472{
473 struct snd_uac_chip *uac = audio_dev->uac;
474
475 free_ep(&uac->p_prm, audio_dev->in_ep);
476}
477EXPORT_SYMBOL_GPL(u_audio_stop_playback);
478
479int g_audio_setup(struct g_audio *g_audio, const char *pcm_name,
480 const char *card_name)
481{
482 struct snd_uac_chip *uac;
483 struct snd_card *card;
484 struct snd_pcm *pcm;
485 struct uac_params *params;
486 int p_chmask, c_chmask;
487 int err;
488
489 if (!g_audio)
490 return -EINVAL;
491
492 uac = kzalloc(sizeof(*uac), GFP_KERNEL);
493 if (!uac)
494 return -ENOMEM;
495 g_audio->uac = uac;
496 uac->audio_dev = g_audio;
497
498 params = &g_audio->params;
499 p_chmask = params->p_chmask;
500 c_chmask = params->c_chmask;
501
502 if (c_chmask) {
503 struct uac_rtd_params *prm = &uac->c_prm;
504
505 uac->c_prm.uac = uac;
506 prm->max_psize = g_audio->out_ep_maxpsize;
507
508 prm->ureq = kcalloc(params->req_number, sizeof(struct uac_req),
509 GFP_KERNEL);
510 if (!prm->ureq) {
511 err = -ENOMEM;
512 goto fail;
513 }
514
515 prm->rbuf = kcalloc(params->req_number, prm->max_psize,
516 GFP_KERNEL);
517 if (!prm->rbuf) {
518 prm->max_psize = 0;
519 err = -ENOMEM;
520 goto fail;
521 }
522 }
523
524 if (p_chmask) {
525 struct uac_rtd_params *prm = &uac->p_prm;
526
527 uac->p_prm.uac = uac;
528 prm->max_psize = g_audio->in_ep_maxpsize;
529
530 prm->ureq = kcalloc(params->req_number, sizeof(struct uac_req),
531 GFP_KERNEL);
532 if (!prm->ureq) {
533 err = -ENOMEM;
534 goto fail;
535 }
536
537 prm->rbuf = kcalloc(params->req_number, prm->max_psize,
538 GFP_KERNEL);
539 if (!prm->rbuf) {
540 prm->max_psize = 0;
541 err = -ENOMEM;
542 goto fail;
543 }
544 }
545
546
547 err = snd_card_new(&g_audio->gadget->dev,
548 -1, NULL, THIS_MODULE, 0, &card);
549 if (err < 0)
550 goto fail;
551
552 uac->card = card;
553
554
555
556
557
558 err = snd_pcm_new(uac->card, pcm_name, 0,
559 p_chmask ? 1 : 0, c_chmask ? 1 : 0, &pcm);
560 if (err < 0)
561 goto snd_fail;
562
563 strlcpy(pcm->name, pcm_name, sizeof(pcm->name));
564 pcm->private_data = uac;
565 uac->pcm = pcm;
566
567 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &uac_pcm_ops);
568 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &uac_pcm_ops);
569
570 strlcpy(card->driver, card_name, sizeof(card->driver));
571 strlcpy(card->shortname, card_name, sizeof(card->shortname));
572 sprintf(card->longname, "%s %i", card_name, card->dev->id);
573
574 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
575 NULL, 0, BUFF_SIZE_MAX);
576
577 err = snd_card_register(card);
578
579 if (!err)
580 return 0;
581
582snd_fail:
583 snd_card_free(card);
584fail:
585 kfree(uac->p_prm.ureq);
586 kfree(uac->c_prm.ureq);
587 kfree(uac->p_prm.rbuf);
588 kfree(uac->c_prm.rbuf);
589 kfree(uac);
590
591 return err;
592}
593EXPORT_SYMBOL_GPL(g_audio_setup);
594
595void g_audio_cleanup(struct g_audio *g_audio)
596{
597 struct snd_uac_chip *uac;
598 struct snd_card *card;
599
600 if (!g_audio || !g_audio->uac)
601 return;
602
603 uac = g_audio->uac;
604 card = uac->card;
605 if (card)
606 snd_card_free(card);
607
608 kfree(uac->p_prm.ureq);
609 kfree(uac->c_prm.ureq);
610 kfree(uac->p_prm.rbuf);
611 kfree(uac->c_prm.rbuf);
612 kfree(uac);
613}
614EXPORT_SYMBOL_GPL(g_audio_cleanup);
615
616MODULE_LICENSE("GPL");
617MODULE_DESCRIPTION("USB gadget \"ALSA sound card\" utilities");
618MODULE_AUTHOR("Ruslan Bilovol");
619
