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1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  */
4 
5 #include <linux/init.h>
6 #include <linux/slab.h>
7 #include <linux/bitrev.h>
8 #include <linux/ratelimit.h>
9 #include <linux/usb.h>
10 #include <linux/usb/audio.h>
11 #include <linux/usb/audio-v2.h>
12 
13 #include <sound/core.h>
14 #include <sound/pcm.h>
15 #include <sound/pcm_params.h>
16 
17 #include <trace/hooks/audio_usboffload.h>
18 
19 #include "usbaudio.h"
20 #include "card.h"
21 #include "quirks.h"
22 #include "endpoint.h"
23 #include "helper.h"
24 #include "pcm.h"
25 #include "clock.h"
26 #include "power.h"
27 #include "media.h"
28 #include "implicit.h"
29 
30 #define SUBSTREAM_FLAG_DATA_EP_STARTED	0
31 #define SUBSTREAM_FLAG_SYNC_EP_STARTED	1
32 
33 /* return the estimated delay based on USB frame counters */
snd_usb_pcm_delay(struct snd_usb_substream * subs,struct snd_pcm_runtime * runtime)34 static snd_pcm_uframes_t snd_usb_pcm_delay(struct snd_usb_substream *subs,
35 					   struct snd_pcm_runtime *runtime)
36 {
37 	unsigned int current_frame_number;
38 	unsigned int frame_diff;
39 	int est_delay;
40 	int queued;
41 
42 	if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK) {
43 		queued = bytes_to_frames(runtime, subs->inflight_bytes);
44 		if (!queued)
45 			return 0;
46 	} else if (!subs->running) {
47 		return 0;
48 	}
49 
50 	current_frame_number = usb_get_current_frame_number(subs->dev);
51 	/*
52 	 * HCD implementations use different widths, use lower 8 bits.
53 	 * The delay will be managed up to 256ms, which is more than
54 	 * enough
55 	 */
56 	frame_diff = (current_frame_number - subs->last_frame_number) & 0xff;
57 
58 	/* Approximation based on number of samples per USB frame (ms),
59 	   some truncation for 44.1 but the estimate is good enough */
60 	est_delay = frame_diff * runtime->rate / 1000;
61 
62 	if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK) {
63 		est_delay = queued - est_delay;
64 		if (est_delay < 0)
65 			est_delay = 0;
66 	}
67 
68 	return est_delay;
69 }
70 
71 /*
72  * return the current pcm pointer.  just based on the hwptr_done value.
73  */
snd_usb_pcm_pointer(struct snd_pcm_substream * substream)74 static snd_pcm_uframes_t snd_usb_pcm_pointer(struct snd_pcm_substream *substream)
75 {
76 	struct snd_pcm_runtime *runtime = substream->runtime;
77 	struct snd_usb_substream *subs = runtime->private_data;
78 	unsigned int hwptr_done;
79 
80 	if (atomic_read(&subs->stream->chip->shutdown))
81 		return SNDRV_PCM_POS_XRUN;
82 	spin_lock(&subs->lock);
83 	hwptr_done = subs->hwptr_done;
84 	runtime->delay = snd_usb_pcm_delay(subs, runtime);
85 	spin_unlock(&subs->lock);
86 	return bytes_to_frames(runtime, hwptr_done);
87 }
88 
89 /*
90  * find a matching audio format
91  */
92 static const struct audioformat *
find_format(struct list_head * fmt_list_head,snd_pcm_format_t format,unsigned int rate,unsigned int channels,bool strict_match,struct snd_usb_substream * subs)93 find_format(struct list_head *fmt_list_head, snd_pcm_format_t format,
94 	    unsigned int rate, unsigned int channels, bool strict_match,
95 	    struct snd_usb_substream *subs)
96 {
97 	const struct audioformat *fp;
98 	const struct audioformat *found = NULL;
99 	int cur_attr = 0, attr;
100 	bool need_ignore = false;
101 
102 	list_for_each_entry(fp, fmt_list_head, list) {
103 		if (strict_match) {
104 			if (!(fp->formats & pcm_format_to_bits(format)))
105 				continue;
106 			if (fp->channels != channels)
107 				continue;
108 		}
109 		if (rate < fp->rate_min || rate > fp->rate_max)
110 			continue;
111 		if (!(fp->rates & SNDRV_PCM_RATE_CONTINUOUS)) {
112 			unsigned int i;
113 			for (i = 0; i < fp->nr_rates; i++)
114 				if (fp->rate_table[i] == rate)
115 					break;
116 			if (i >= fp->nr_rates)
117 				continue;
118 		}
119 		attr = fp->ep_attr & USB_ENDPOINT_SYNCTYPE;
120 
121 		trace_android_vh_audio_usb_offload_synctype(subs, attr, &need_ignore);
122 		if (need_ignore)
123 			continue;
124 
125 		if (!found) {
126 			found = fp;
127 			cur_attr = attr;
128 			continue;
129 		}
130 		/* avoid async out and adaptive in if the other method
131 		 * supports the same format.
132 		 * this is a workaround for the case like
133 		 * M-audio audiophile USB.
134 		 */
135 		if (subs && attr != cur_attr) {
136 			if ((attr == USB_ENDPOINT_SYNC_ASYNC &&
137 			     subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
138 			    (attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
139 			     subs->direction == SNDRV_PCM_STREAM_CAPTURE))
140 				continue;
141 			if ((cur_attr == USB_ENDPOINT_SYNC_ASYNC &&
142 			     subs->direction == SNDRV_PCM_STREAM_PLAYBACK) ||
143 			    (cur_attr == USB_ENDPOINT_SYNC_ADAPTIVE &&
144 			     subs->direction == SNDRV_PCM_STREAM_CAPTURE)) {
145 				found = fp;
146 				cur_attr = attr;
147 				continue;
148 			}
149 		}
150 		/* find the format with the largest max. packet size */
151 		if (fp->maxpacksize > found->maxpacksize) {
152 			found = fp;
153 			cur_attr = attr;
154 		}
155 	}
156 	return found;
157 }
158 
159 static const struct audioformat *
find_substream_format(struct snd_usb_substream * subs,const struct snd_pcm_hw_params * params)160 find_substream_format(struct snd_usb_substream *subs,
161 		      const struct snd_pcm_hw_params *params)
162 {
163 	return find_format(&subs->fmt_list, params_format(params),
164 			   params_rate(params), params_channels(params),
165 			   true, subs);
166 }
167 
init_pitch_v1(struct snd_usb_audio * chip,int ep)168 static int init_pitch_v1(struct snd_usb_audio *chip, int ep)
169 {
170 	struct usb_device *dev = chip->dev;
171 	unsigned char data[1];
172 	int err;
173 
174 	data[0] = 1;
175 	err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
176 			      USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT,
177 			      UAC_EP_CS_ATTR_PITCH_CONTROL << 8, ep,
178 			      data, sizeof(data));
179 	return err;
180 }
181 
init_pitch_v2(struct snd_usb_audio * chip,int ep)182 static int init_pitch_v2(struct snd_usb_audio *chip, int ep)
183 {
184 	struct usb_device *dev = chip->dev;
185 	unsigned char data[1];
186 	int err;
187 
188 	data[0] = 1;
189 	err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC2_CS_CUR,
190 			      USB_TYPE_CLASS | USB_RECIP_ENDPOINT | USB_DIR_OUT,
191 			      UAC2_EP_CS_PITCH << 8, 0,
192 			      data, sizeof(data));
193 	return err;
194 }
195 
196 /*
197  * initialize the pitch control and sample rate
198  */
snd_usb_init_pitch(struct snd_usb_audio * chip,const struct audioformat * fmt)199 int snd_usb_init_pitch(struct snd_usb_audio *chip,
200 		       const struct audioformat *fmt)
201 {
202 	int err;
203 
204 	/* if endpoint doesn't have pitch control, bail out */
205 	if (!(fmt->attributes & UAC_EP_CS_ATTR_PITCH_CONTROL))
206 		return 0;
207 
208 	usb_audio_dbg(chip, "enable PITCH for EP 0x%x\n", fmt->endpoint);
209 
210 	switch (fmt->protocol) {
211 	case UAC_VERSION_1:
212 		err = init_pitch_v1(chip, fmt->endpoint);
213 		break;
214 	case UAC_VERSION_2:
215 		err = init_pitch_v2(chip, fmt->endpoint);
216 		break;
217 	default:
218 		return 0;
219 	}
220 
221 	if (err < 0) {
222 		usb_audio_err(chip, "failed to enable PITCH for EP 0x%x\n",
223 			      fmt->endpoint);
224 		return err;
225 	}
226 
227 	return 0;
228 }
229 
stop_endpoints(struct snd_usb_substream * subs,bool keep_pending)230 static bool stop_endpoints(struct snd_usb_substream *subs, bool keep_pending)
231 {
232 	bool stopped = 0;
233 
234 	if (test_and_clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags)) {
235 		snd_usb_endpoint_stop(subs->sync_endpoint, keep_pending);
236 		stopped = true;
237 	}
238 	if (test_and_clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags)) {
239 		snd_usb_endpoint_stop(subs->data_endpoint, keep_pending);
240 		stopped = true;
241 	}
242 	return stopped;
243 }
244 
start_endpoints(struct snd_usb_substream * subs)245 static int start_endpoints(struct snd_usb_substream *subs)
246 {
247 	int err;
248 
249 	if (!subs->data_endpoint)
250 		return -EINVAL;
251 
252 	if (!test_and_set_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags)) {
253 		err = snd_usb_endpoint_start(subs->data_endpoint);
254 		if (err < 0) {
255 			clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags);
256 			goto error;
257 		}
258 	}
259 
260 	if (subs->sync_endpoint &&
261 	    !test_and_set_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags)) {
262 		err = snd_usb_endpoint_start(subs->sync_endpoint);
263 		if (err < 0) {
264 			clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
265 			goto error;
266 		}
267 	}
268 
269 	return 0;
270 
271  error:
272 	stop_endpoints(subs, false);
273 	return err;
274 }
275 
sync_pending_stops(struct snd_usb_substream * subs)276 static void sync_pending_stops(struct snd_usb_substream *subs)
277 {
278 	snd_usb_endpoint_sync_pending_stop(subs->sync_endpoint);
279 	snd_usb_endpoint_sync_pending_stop(subs->data_endpoint);
280 }
281 
282 /* PCM sync_stop callback */
snd_usb_pcm_sync_stop(struct snd_pcm_substream * substream)283 static int snd_usb_pcm_sync_stop(struct snd_pcm_substream *substream)
284 {
285 	struct snd_usb_substream *subs = substream->runtime->private_data;
286 
287 	sync_pending_stops(subs);
288 	return 0;
289 }
290 
291 /* Set up sync endpoint */
snd_usb_audioformat_set_sync_ep(struct snd_usb_audio * chip,struct audioformat * fmt)292 int snd_usb_audioformat_set_sync_ep(struct snd_usb_audio *chip,
293 				    struct audioformat *fmt)
294 {
295 	struct usb_device *dev = chip->dev;
296 	struct usb_host_interface *alts;
297 	struct usb_interface_descriptor *altsd;
298 	unsigned int ep, attr, sync_attr;
299 	bool is_playback;
300 	int err;
301 
302 	if (fmt->sync_ep)
303 		return 0; /* already set up */
304 
305 	alts = snd_usb_get_host_interface(chip, fmt->iface, fmt->altsetting);
306 	if (!alts)
307 		return 0;
308 	altsd = get_iface_desc(alts);
309 
310 	err = snd_usb_parse_implicit_fb_quirk(chip, fmt, alts);
311 	if (err > 0)
312 		return 0; /* matched */
313 
314 	/*
315 	 * Generic sync EP handling
316 	 */
317 
318 	if (fmt->ep_idx > 0 || altsd->bNumEndpoints < 2)
319 		return 0;
320 
321 	is_playback = !(get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN);
322 	attr = fmt->ep_attr & USB_ENDPOINT_SYNCTYPE;
323 	if ((is_playback && (attr == USB_ENDPOINT_SYNC_SYNC ||
324 			     attr == USB_ENDPOINT_SYNC_ADAPTIVE)) ||
325 	    (!is_playback && attr != USB_ENDPOINT_SYNC_ADAPTIVE))
326 		return 0;
327 
328 	sync_attr = get_endpoint(alts, 1)->bmAttributes;
329 
330 	/*
331 	 * In case of illegal SYNC_NONE for OUT endpoint, we keep going to see
332 	 * if we don't find a sync endpoint, as on M-Audio Transit. In case of
333 	 * error fall back to SYNC mode and don't create sync endpoint
334 	 */
335 
336 	/* check sync-pipe endpoint */
337 	/* ... and check descriptor size before accessing bSynchAddress
338 	   because there is a version of the SB Audigy 2 NX firmware lacking
339 	   the audio fields in the endpoint descriptors */
340 	if ((sync_attr & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_ISOC ||
341 	    (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
342 	     get_endpoint(alts, 1)->bSynchAddress != 0)) {
343 		dev_err(&dev->dev,
344 			"%d:%d : invalid sync pipe. bmAttributes %02x, bLength %d, bSynchAddress %02x\n",
345 			   fmt->iface, fmt->altsetting,
346 			   get_endpoint(alts, 1)->bmAttributes,
347 			   get_endpoint(alts, 1)->bLength,
348 			   get_endpoint(alts, 1)->bSynchAddress);
349 		if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
350 			return 0;
351 		return -EINVAL;
352 	}
353 	ep = get_endpoint(alts, 1)->bEndpointAddress;
354 	if (get_endpoint(alts, 0)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
355 	    get_endpoint(alts, 0)->bSynchAddress != 0 &&
356 	    ((is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress | USB_DIR_IN)) ||
357 	     (!is_playback && ep != (unsigned int)(get_endpoint(alts, 0)->bSynchAddress & ~USB_DIR_IN)))) {
358 		dev_err(&dev->dev,
359 			"%d:%d : invalid sync pipe. is_playback %d, ep %02x, bSynchAddress %02x\n",
360 			   fmt->iface, fmt->altsetting,
361 			   is_playback, ep, get_endpoint(alts, 0)->bSynchAddress);
362 		if (is_playback && attr == USB_ENDPOINT_SYNC_NONE)
363 			return 0;
364 		return -EINVAL;
365 	}
366 
367 	fmt->sync_ep = ep;
368 	fmt->sync_iface = altsd->bInterfaceNumber;
369 	fmt->sync_altsetting = altsd->bAlternateSetting;
370 	fmt->sync_ep_idx = 1;
371 	if ((sync_attr & USB_ENDPOINT_USAGE_MASK) == USB_ENDPOINT_USAGE_IMPLICIT_FB)
372 		fmt->implicit_fb = 1;
373 
374 	dev_dbg(&dev->dev, "%d:%d: found sync_ep=0x%x, iface=%d, alt=%d, implicit_fb=%d\n",
375 		fmt->iface, fmt->altsetting, fmt->sync_ep, fmt->sync_iface,
376 		fmt->sync_altsetting, fmt->implicit_fb);
377 
378 	return 0;
379 }
380 
snd_usb_pcm_change_state(struct snd_usb_substream * subs,int state)381 static int snd_usb_pcm_change_state(struct snd_usb_substream *subs, int state)
382 {
383 	int ret;
384 
385 	if (!subs->str_pd)
386 		return 0;
387 
388 	ret = snd_usb_power_domain_set(subs->stream->chip, subs->str_pd, state);
389 	if (ret < 0) {
390 		dev_err(&subs->dev->dev,
391 			"Cannot change Power Domain ID: %d to state: %d. Err: %d\n",
392 			subs->str_pd->pd_id, state, ret);
393 		return ret;
394 	}
395 
396 	return 0;
397 }
398 
snd_usb_pcm_suspend(struct snd_usb_stream * as)399 int snd_usb_pcm_suspend(struct snd_usb_stream *as)
400 {
401 	int ret;
402 
403 	ret = snd_usb_pcm_change_state(&as->substream[0], UAC3_PD_STATE_D2);
404 	if (ret < 0)
405 		return ret;
406 
407 	ret = snd_usb_pcm_change_state(&as->substream[1], UAC3_PD_STATE_D2);
408 	if (ret < 0)
409 		return ret;
410 
411 	return 0;
412 }
413 
snd_usb_pcm_resume(struct snd_usb_stream * as)414 int snd_usb_pcm_resume(struct snd_usb_stream *as)
415 {
416 	int ret;
417 
418 	ret = snd_usb_pcm_change_state(&as->substream[0], UAC3_PD_STATE_D1);
419 	if (ret < 0)
420 		return ret;
421 
422 	ret = snd_usb_pcm_change_state(&as->substream[1], UAC3_PD_STATE_D1);
423 	if (ret < 0)
424 		return ret;
425 
426 	return 0;
427 }
428 
close_endpoints(struct snd_usb_audio * chip,struct snd_usb_substream * subs)429 static void close_endpoints(struct snd_usb_audio *chip,
430 			    struct snd_usb_substream *subs)
431 {
432 	if (subs->data_endpoint) {
433 		snd_usb_endpoint_set_sync(chip, subs->data_endpoint, NULL);
434 		snd_usb_endpoint_close(chip, subs->data_endpoint);
435 		subs->data_endpoint = NULL;
436 	}
437 
438 	if (subs->sync_endpoint) {
439 		snd_usb_endpoint_close(chip, subs->sync_endpoint);
440 		subs->sync_endpoint = NULL;
441 	}
442 }
443 
configure_endpoints(struct snd_usb_audio * chip,struct snd_usb_substream * subs)444 static int configure_endpoints(struct snd_usb_audio *chip,
445 			       struct snd_usb_substream *subs)
446 {
447 	int err;
448 
449 	if (subs->data_endpoint->need_setup) {
450 		/* stop any running stream beforehand */
451 		if (stop_endpoints(subs, false))
452 			sync_pending_stops(subs);
453 		if (subs->sync_endpoint) {
454 			err = snd_usb_endpoint_configure(chip, subs->sync_endpoint);
455 			if (err < 0)
456 				return err;
457 		}
458 		err = snd_usb_endpoint_configure(chip, subs->data_endpoint);
459 		if (err < 0)
460 			return err;
461 		snd_usb_set_format_quirk(subs, subs->cur_audiofmt);
462 	} else {
463 		if (subs->sync_endpoint) {
464 			err = snd_usb_endpoint_configure(chip, subs->sync_endpoint);
465 			if (err < 0)
466 				return err;
467 		}
468 	}
469 
470 	return 0;
471 }
472 
473 /*
474  * hw_params callback
475  *
476  * allocate a buffer and set the given audio format.
477  *
478  * so far we use a physically linear buffer although packetize transfer
479  * doesn't need a continuous area.
480  * if sg buffer is supported on the later version of alsa, we'll follow
481  * that.
482  */
snd_usb_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * hw_params)483 static int snd_usb_hw_params(struct snd_pcm_substream *substream,
484 			     struct snd_pcm_hw_params *hw_params)
485 {
486 	struct snd_usb_substream *subs = substream->runtime->private_data;
487 	struct snd_usb_audio *chip = subs->stream->chip;
488 	const struct audioformat *fmt;
489 	const struct audioformat *sync_fmt;
490 	int ret;
491 
492 	ret = snd_media_start_pipeline(subs);
493 	if (ret)
494 		return ret;
495 
496 	fmt = find_substream_format(subs, hw_params);
497 	if (!fmt) {
498 		usb_audio_dbg(chip,
499 			      "cannot find format: format=%s, rate=%d, channels=%d\n",
500 			      snd_pcm_format_name(params_format(hw_params)),
501 			      params_rate(hw_params), params_channels(hw_params));
502 		ret = -EINVAL;
503 		goto stop_pipeline;
504 	}
505 
506 	if (fmt->implicit_fb) {
507 		sync_fmt = snd_usb_find_implicit_fb_sync_format(chip, fmt,
508 								hw_params,
509 								!substream->stream);
510 		if (!sync_fmt) {
511 			usb_audio_dbg(chip,
512 				      "cannot find sync format: ep=0x%x, iface=%d:%d, format=%s, rate=%d, channels=%d\n",
513 				      fmt->sync_ep, fmt->sync_iface,
514 				      fmt->sync_altsetting,
515 				      snd_pcm_format_name(params_format(hw_params)),
516 				      params_rate(hw_params), params_channels(hw_params));
517 			ret = -EINVAL;
518 			goto stop_pipeline;
519 		}
520 	} else {
521 		sync_fmt = fmt;
522 	}
523 
524 	ret = snd_usb_lock_shutdown(chip);
525 	if (ret < 0)
526 		goto stop_pipeline;
527 
528 	ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D0);
529 	if (ret < 0)
530 		goto unlock;
531 
532 	if (subs->data_endpoint) {
533 		if (snd_usb_endpoint_compatible(chip, subs->data_endpoint,
534 						fmt, hw_params))
535 			goto unlock;
536 		if (stop_endpoints(subs, false))
537 			sync_pending_stops(subs);
538 		close_endpoints(chip, subs);
539 	}
540 
541 	subs->data_endpoint = snd_usb_endpoint_open(chip, fmt, hw_params, false);
542 	if (!subs->data_endpoint) {
543 		ret = -EINVAL;
544 		goto unlock;
545 	}
546 
547 	if (fmt->sync_ep) {
548 		subs->sync_endpoint = snd_usb_endpoint_open(chip, sync_fmt,
549 							    hw_params,
550 							    fmt == sync_fmt);
551 		if (!subs->sync_endpoint) {
552 			ret = -EINVAL;
553 			goto unlock;
554 		}
555 
556 		snd_usb_endpoint_set_sync(chip, subs->data_endpoint,
557 					  subs->sync_endpoint);
558 	}
559 
560 	mutex_lock(&chip->mutex);
561 	subs->cur_audiofmt = fmt;
562 	mutex_unlock(&chip->mutex);
563 
564 	if (subs->sync_endpoint) {
565 		ret = snd_usb_endpoint_set_params(chip, subs->sync_endpoint);
566 		if (ret < 0)
567 			goto unlock;
568 	}
569 
570 	ret = snd_usb_endpoint_set_params(chip, subs->data_endpoint);
571 
572  unlock:
573 	if (ret < 0)
574 		close_endpoints(chip, subs);
575 
576 	snd_usb_unlock_shutdown(chip);
577  stop_pipeline:
578 	if (ret < 0)
579 		snd_media_stop_pipeline(subs);
580 
581 	return ret;
582 }
583 
584 /*
585  * hw_free callback
586  *
587  * reset the audio format and release the buffer
588  */
snd_usb_hw_free(struct snd_pcm_substream * substream)589 static int snd_usb_hw_free(struct snd_pcm_substream *substream)
590 {
591 	struct snd_usb_substream *subs = substream->runtime->private_data;
592 	struct snd_usb_audio *chip = subs->stream->chip;
593 
594 	snd_media_stop_pipeline(subs);
595 	mutex_lock(&chip->mutex);
596 	subs->cur_audiofmt = NULL;
597 	mutex_unlock(&chip->mutex);
598 	if (!snd_usb_lock_shutdown(chip)) {
599 		if (stop_endpoints(subs, false))
600 			sync_pending_stops(subs);
601 		close_endpoints(chip, subs);
602 		snd_usb_unlock_shutdown(chip);
603 	}
604 
605 	return 0;
606 }
607 
608 /* free-wheeling mode? (e.g. dmix) */
in_free_wheeling_mode(struct snd_pcm_runtime * runtime)609 static int in_free_wheeling_mode(struct snd_pcm_runtime *runtime)
610 {
611 	return runtime->stop_threshold > runtime->buffer_size;
612 }
613 
614 /* check whether early start is needed for playback stream */
lowlatency_playback_available(struct snd_pcm_runtime * runtime,struct snd_usb_substream * subs)615 static int lowlatency_playback_available(struct snd_pcm_runtime *runtime,
616 					 struct snd_usb_substream *subs)
617 {
618 	struct snd_usb_audio *chip = subs->stream->chip;
619 
620 	if (subs->direction == SNDRV_PCM_STREAM_CAPTURE)
621 		return false;
622 	/* disabled via module option? */
623 	if (!chip->lowlatency)
624 		return false;
625 	if (in_free_wheeling_mode(runtime))
626 		return false;
627 	/* implicit feedback mode has own operation mode */
628 	if (snd_usb_endpoint_implicit_feedback_sink(subs->data_endpoint))
629 		return false;
630 	return true;
631 }
632 
633 /*
634  * prepare callback
635  *
636  * only a few subtle things...
637  */
snd_usb_pcm_prepare(struct snd_pcm_substream * substream)638 static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
639 {
640 	struct snd_pcm_runtime *runtime = substream->runtime;
641 	struct snd_usb_substream *subs = runtime->private_data;
642 	struct snd_usb_audio *chip = subs->stream->chip;
643 	int ret;
644 
645 	ret = snd_usb_lock_shutdown(chip);
646 	if (ret < 0)
647 		return ret;
648 	if (snd_BUG_ON(!subs->data_endpoint)) {
649 		ret = -EIO;
650 		goto unlock;
651 	}
652 
653 	ret = configure_endpoints(chip, subs);
654 	if (ret < 0)
655 		goto unlock;
656 
657 	/* reset the pointer */
658 	subs->buffer_bytes = frames_to_bytes(runtime, runtime->buffer_size);
659 	subs->inflight_bytes = 0;
660 	subs->hwptr_done = 0;
661 	subs->transfer_done = 0;
662 	subs->last_frame_number = 0;
663 	subs->period_elapsed_pending = 0;
664 	runtime->delay = 0;
665 
666 	subs->lowlatency_playback = lowlatency_playback_available(runtime, subs);
667 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
668 	    !subs->lowlatency_playback)
669 		ret = start_endpoints(subs);
670 
671  unlock:
672 	snd_usb_unlock_shutdown(chip);
673 	return ret;
674 }
675 
676 /*
677  * h/w constraints
678  */
679 
680 #ifdef HW_CONST_DEBUG
681 #define hwc_debug(fmt, args...) pr_debug(fmt, ##args)
682 #else
683 #define hwc_debug(fmt, args...) do { } while(0)
684 #endif
685 
686 static const struct snd_pcm_hardware snd_usb_hardware =
687 {
688 	.info =			SNDRV_PCM_INFO_MMAP |
689 				SNDRV_PCM_INFO_MMAP_VALID |
690 				SNDRV_PCM_INFO_BATCH |
691 				SNDRV_PCM_INFO_INTERLEAVED |
692 				SNDRV_PCM_INFO_BLOCK_TRANSFER |
693 				SNDRV_PCM_INFO_PAUSE,
694 	.channels_min =		1,
695 	.channels_max =		256,
696 	.buffer_bytes_max =	INT_MAX, /* limited by BUFFER_TIME later */
697 	.period_bytes_min =	64,
698 	.period_bytes_max =	INT_MAX, /* limited by PERIOD_TIME later */
699 	.periods_min =		2,
700 	.periods_max =		1024,
701 };
702 
hw_check_valid_format(struct snd_usb_substream * subs,struct snd_pcm_hw_params * params,const struct audioformat * fp)703 static int hw_check_valid_format(struct snd_usb_substream *subs,
704 				 struct snd_pcm_hw_params *params,
705 				 const struct audioformat *fp)
706 {
707 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
708 	struct snd_interval *ct = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
709 	struct snd_mask *fmts = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
710 	struct snd_interval *pt = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
711 	struct snd_mask check_fmts;
712 	unsigned int ptime;
713 
714 	/* check the format */
715 	snd_mask_none(&check_fmts);
716 	check_fmts.bits[0] = (u32)fp->formats;
717 	check_fmts.bits[1] = (u32)(fp->formats >> 32);
718 	snd_mask_intersect(&check_fmts, fmts);
719 	if (snd_mask_empty(&check_fmts)) {
720 		hwc_debug("   > check: no supported format 0x%llx\n", fp->formats);
721 		return 0;
722 	}
723 	/* check the channels */
724 	if (fp->channels < ct->min || fp->channels > ct->max) {
725 		hwc_debug("   > check: no valid channels %d (%d/%d)\n", fp->channels, ct->min, ct->max);
726 		return 0;
727 	}
728 	/* check the rate is within the range */
729 	if (fp->rate_min > it->max || (fp->rate_min == it->max && it->openmax)) {
730 		hwc_debug("   > check: rate_min %d > max %d\n", fp->rate_min, it->max);
731 		return 0;
732 	}
733 	if (fp->rate_max < it->min || (fp->rate_max == it->min && it->openmin)) {
734 		hwc_debug("   > check: rate_max %d < min %d\n", fp->rate_max, it->min);
735 		return 0;
736 	}
737 	/* check whether the period time is >= the data packet interval */
738 	if (subs->speed != USB_SPEED_FULL) {
739 		ptime = 125 * (1 << fp->datainterval);
740 		if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
741 			hwc_debug("   > check: ptime %u > max %u\n", ptime, pt->max);
742 			return 0;
743 		}
744 	}
745 	return 1;
746 }
747 
apply_hw_params_minmax(struct snd_interval * it,unsigned int rmin,unsigned int rmax)748 static int apply_hw_params_minmax(struct snd_interval *it, unsigned int rmin,
749 				  unsigned int rmax)
750 {
751 	int changed;
752 
753 	if (rmin > rmax) {
754 		hwc_debug("  --> get empty\n");
755 		it->empty = 1;
756 		return -EINVAL;
757 	}
758 
759 	changed = 0;
760 	if (it->min < rmin) {
761 		it->min = rmin;
762 		it->openmin = 0;
763 		changed = 1;
764 	}
765 	if (it->max > rmax) {
766 		it->max = rmax;
767 		it->openmax = 0;
768 		changed = 1;
769 	}
770 	if (snd_interval_checkempty(it)) {
771 		it->empty = 1;
772 		return -EINVAL;
773 	}
774 	hwc_debug("  --> (%d, %d) (changed = %d)\n", it->min, it->max, changed);
775 	return changed;
776 }
777 
hw_rule_rate(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)778 static int hw_rule_rate(struct snd_pcm_hw_params *params,
779 			struct snd_pcm_hw_rule *rule)
780 {
781 	struct snd_usb_substream *subs = rule->private;
782 	struct snd_usb_audio *chip = subs->stream->chip;
783 	const struct audioformat *fp;
784 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
785 	unsigned int rmin, rmax, r;
786 	int i;
787 
788 	hwc_debug("hw_rule_rate: (%d,%d)\n", it->min, it->max);
789 	rmin = UINT_MAX;
790 	rmax = 0;
791 	list_for_each_entry(fp, &subs->fmt_list, list) {
792 		if (!hw_check_valid_format(subs, params, fp))
793 			continue;
794 		r = snd_usb_endpoint_get_clock_rate(chip, fp->clock);
795 		if (r > 0) {
796 			if (!snd_interval_test(it, r))
797 				continue;
798 			rmin = min(rmin, r);
799 			rmax = max(rmax, r);
800 			continue;
801 		}
802 		if (fp->rate_table && fp->nr_rates) {
803 			for (i = 0; i < fp->nr_rates; i++) {
804 				r = fp->rate_table[i];
805 				if (!snd_interval_test(it, r))
806 					continue;
807 				rmin = min(rmin, r);
808 				rmax = max(rmax, r);
809 			}
810 		} else {
811 			rmin = min(rmin, fp->rate_min);
812 			rmax = max(rmax, fp->rate_max);
813 		}
814 	}
815 
816 	return apply_hw_params_minmax(it, rmin, rmax);
817 }
818 
819 
hw_rule_channels(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)820 static int hw_rule_channels(struct snd_pcm_hw_params *params,
821 			    struct snd_pcm_hw_rule *rule)
822 {
823 	struct snd_usb_substream *subs = rule->private;
824 	const struct audioformat *fp;
825 	struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
826 	unsigned int rmin, rmax;
827 
828 	hwc_debug("hw_rule_channels: (%d,%d)\n", it->min, it->max);
829 	rmin = UINT_MAX;
830 	rmax = 0;
831 	list_for_each_entry(fp, &subs->fmt_list, list) {
832 		if (!hw_check_valid_format(subs, params, fp))
833 			continue;
834 		rmin = min(rmin, fp->channels);
835 		rmax = max(rmax, fp->channels);
836 	}
837 
838 	return apply_hw_params_minmax(it, rmin, rmax);
839 }
840 
apply_hw_params_format_bits(struct snd_mask * fmt,u64 fbits)841 static int apply_hw_params_format_bits(struct snd_mask *fmt, u64 fbits)
842 {
843 	u32 oldbits[2];
844 	int changed;
845 
846 	oldbits[0] = fmt->bits[0];
847 	oldbits[1] = fmt->bits[1];
848 	fmt->bits[0] &= (u32)fbits;
849 	fmt->bits[1] &= (u32)(fbits >> 32);
850 	if (!fmt->bits[0] && !fmt->bits[1]) {
851 		hwc_debug("  --> get empty\n");
852 		return -EINVAL;
853 	}
854 	changed = (oldbits[0] != fmt->bits[0] || oldbits[1] != fmt->bits[1]);
855 	hwc_debug("  --> %x:%x (changed = %d)\n", fmt->bits[0], fmt->bits[1], changed);
856 	return changed;
857 }
858 
hw_rule_format(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)859 static int hw_rule_format(struct snd_pcm_hw_params *params,
860 			  struct snd_pcm_hw_rule *rule)
861 {
862 	struct snd_usb_substream *subs = rule->private;
863 	const struct audioformat *fp;
864 	struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
865 	u64 fbits;
866 
867 	hwc_debug("hw_rule_format: %x:%x\n", fmt->bits[0], fmt->bits[1]);
868 	fbits = 0;
869 	list_for_each_entry(fp, &subs->fmt_list, list) {
870 		if (!hw_check_valid_format(subs, params, fp))
871 			continue;
872 		fbits |= fp->formats;
873 	}
874 	return apply_hw_params_format_bits(fmt, fbits);
875 }
876 
hw_rule_period_time(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)877 static int hw_rule_period_time(struct snd_pcm_hw_params *params,
878 			       struct snd_pcm_hw_rule *rule)
879 {
880 	struct snd_usb_substream *subs = rule->private;
881 	const struct audioformat *fp;
882 	struct snd_interval *it;
883 	unsigned char min_datainterval;
884 	unsigned int pmin;
885 
886 	it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
887 	hwc_debug("hw_rule_period_time: (%u,%u)\n", it->min, it->max);
888 	min_datainterval = 0xff;
889 	list_for_each_entry(fp, &subs->fmt_list, list) {
890 		if (!hw_check_valid_format(subs, params, fp))
891 			continue;
892 		min_datainterval = min(min_datainterval, fp->datainterval);
893 	}
894 	if (min_datainterval == 0xff) {
895 		hwc_debug("  --> get empty\n");
896 		it->empty = 1;
897 		return -EINVAL;
898 	}
899 	pmin = 125 * (1 << min_datainterval);
900 
901 	return apply_hw_params_minmax(it, pmin, UINT_MAX);
902 }
903 
904 /* get the EP or the sync EP for implicit fb when it's already set up */
905 static const struct snd_usb_endpoint *
get_sync_ep_from_substream(struct snd_usb_substream * subs)906 get_sync_ep_from_substream(struct snd_usb_substream *subs)
907 {
908 	struct snd_usb_audio *chip = subs->stream->chip;
909 	const struct audioformat *fp;
910 	const struct snd_usb_endpoint *ep;
911 
912 	list_for_each_entry(fp, &subs->fmt_list, list) {
913 		ep = snd_usb_get_endpoint(chip, fp->endpoint);
914 		if (ep && ep->cur_audiofmt) {
915 			/* if EP is already opened solely for this substream,
916 			 * we still allow us to change the parameter; otherwise
917 			 * this substream has to follow the existing parameter
918 			 */
919 			if (ep->cur_audiofmt != subs->cur_audiofmt || ep->opened > 1)
920 				return ep;
921 		}
922 		if (!fp->implicit_fb)
923 			continue;
924 		/* for the implicit fb, check the sync ep as well */
925 		ep = snd_usb_get_endpoint(chip, fp->sync_ep);
926 		if (ep && ep->cur_audiofmt) {
927 			/* ditto, if the sync (data) ep is used by others,
928 			 * this stream is restricted by the sync ep
929 			 */
930 			if (ep != subs->sync_endpoint || ep->opened > 1)
931 				return ep;
932 		}
933 	}
934 	return NULL;
935 }
936 
937 /* additional hw constraints for implicit feedback mode */
hw_rule_format_implicit_fb(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)938 static int hw_rule_format_implicit_fb(struct snd_pcm_hw_params *params,
939 				      struct snd_pcm_hw_rule *rule)
940 {
941 	struct snd_usb_substream *subs = rule->private;
942 	const struct snd_usb_endpoint *ep;
943 	struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
944 
945 	ep = get_sync_ep_from_substream(subs);
946 	if (!ep)
947 		return 0;
948 
949 	hwc_debug("applying %s\n", __func__);
950 	return apply_hw_params_format_bits(fmt, pcm_format_to_bits(ep->cur_format));
951 }
952 
hw_rule_rate_implicit_fb(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)953 static int hw_rule_rate_implicit_fb(struct snd_pcm_hw_params *params,
954 				    struct snd_pcm_hw_rule *rule)
955 {
956 	struct snd_usb_substream *subs = rule->private;
957 	const struct snd_usb_endpoint *ep;
958 	struct snd_interval *it;
959 
960 	ep = get_sync_ep_from_substream(subs);
961 	if (!ep)
962 		return 0;
963 
964 	hwc_debug("applying %s\n", __func__);
965 	it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
966 	return apply_hw_params_minmax(it, ep->cur_rate, ep->cur_rate);
967 }
968 
hw_rule_period_size_implicit_fb(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)969 static int hw_rule_period_size_implicit_fb(struct snd_pcm_hw_params *params,
970 					   struct snd_pcm_hw_rule *rule)
971 {
972 	struct snd_usb_substream *subs = rule->private;
973 	const struct snd_usb_endpoint *ep;
974 	struct snd_interval *it;
975 
976 	ep = get_sync_ep_from_substream(subs);
977 	if (!ep)
978 		return 0;
979 
980 	hwc_debug("applying %s\n", __func__);
981 	it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
982 	return apply_hw_params_minmax(it, ep->cur_period_frames,
983 				      ep->cur_period_frames);
984 }
985 
hw_rule_periods_implicit_fb(struct snd_pcm_hw_params * params,struct snd_pcm_hw_rule * rule)986 static int hw_rule_periods_implicit_fb(struct snd_pcm_hw_params *params,
987 				       struct snd_pcm_hw_rule *rule)
988 {
989 	struct snd_usb_substream *subs = rule->private;
990 	const struct snd_usb_endpoint *ep;
991 	struct snd_interval *it;
992 
993 	ep = get_sync_ep_from_substream(subs);
994 	if (!ep)
995 		return 0;
996 
997 	hwc_debug("applying %s\n", __func__);
998 	it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIODS);
999 	return apply_hw_params_minmax(it, ep->cur_buffer_periods,
1000 				      ep->cur_buffer_periods);
1001 }
1002 
1003 /*
1004  * set up the runtime hardware information.
1005  */
1006 
setup_hw_info(struct snd_pcm_runtime * runtime,struct snd_usb_substream * subs)1007 static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substream *subs)
1008 {
1009 	const struct audioformat *fp;
1010 	unsigned int pt, ptmin;
1011 	int param_period_time_if_needed = -1;
1012 	int err;
1013 
1014 	runtime->hw.formats = subs->formats;
1015 
1016 	runtime->hw.rate_min = 0x7fffffff;
1017 	runtime->hw.rate_max = 0;
1018 	runtime->hw.channels_min = 256;
1019 	runtime->hw.channels_max = 0;
1020 	runtime->hw.rates = 0;
1021 	ptmin = UINT_MAX;
1022 	/* check min/max rates and channels */
1023 	list_for_each_entry(fp, &subs->fmt_list, list) {
1024 		runtime->hw.rates |= fp->rates;
1025 		if (runtime->hw.rate_min > fp->rate_min)
1026 			runtime->hw.rate_min = fp->rate_min;
1027 		if (runtime->hw.rate_max < fp->rate_max)
1028 			runtime->hw.rate_max = fp->rate_max;
1029 		if (runtime->hw.channels_min > fp->channels)
1030 			runtime->hw.channels_min = fp->channels;
1031 		if (runtime->hw.channels_max < fp->channels)
1032 			runtime->hw.channels_max = fp->channels;
1033 		if (fp->fmt_type == UAC_FORMAT_TYPE_II && fp->frame_size > 0) {
1034 			/* FIXME: there might be more than one audio formats... */
1035 			runtime->hw.period_bytes_min = runtime->hw.period_bytes_max =
1036 				fp->frame_size;
1037 		}
1038 		pt = 125 * (1 << fp->datainterval);
1039 		ptmin = min(ptmin, pt);
1040 	}
1041 
1042 	param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
1043 	if (subs->speed == USB_SPEED_FULL)
1044 		/* full speed devices have fixed data packet interval */
1045 		ptmin = 1000;
1046 	if (ptmin == 1000)
1047 		/* if period time doesn't go below 1 ms, no rules needed */
1048 		param_period_time_if_needed = -1;
1049 
1050 	err = snd_pcm_hw_constraint_minmax(runtime,
1051 					   SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1052 					   ptmin, UINT_MAX);
1053 	if (err < 0)
1054 		return err;
1055 
1056 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1057 				  hw_rule_rate, subs,
1058 				  SNDRV_PCM_HW_PARAM_RATE,
1059 				  SNDRV_PCM_HW_PARAM_FORMAT,
1060 				  SNDRV_PCM_HW_PARAM_CHANNELS,
1061 				  param_period_time_if_needed,
1062 				  -1);
1063 	if (err < 0)
1064 		return err;
1065 
1066 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
1067 				  hw_rule_channels, subs,
1068 				  SNDRV_PCM_HW_PARAM_CHANNELS,
1069 				  SNDRV_PCM_HW_PARAM_FORMAT,
1070 				  SNDRV_PCM_HW_PARAM_RATE,
1071 				  param_period_time_if_needed,
1072 				  -1);
1073 	if (err < 0)
1074 		return err;
1075 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
1076 				  hw_rule_format, subs,
1077 				  SNDRV_PCM_HW_PARAM_FORMAT,
1078 				  SNDRV_PCM_HW_PARAM_RATE,
1079 				  SNDRV_PCM_HW_PARAM_CHANNELS,
1080 				  param_period_time_if_needed,
1081 				  -1);
1082 	if (err < 0)
1083 		return err;
1084 	if (param_period_time_if_needed >= 0) {
1085 		err = snd_pcm_hw_rule_add(runtime, 0,
1086 					  SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1087 					  hw_rule_period_time, subs,
1088 					  SNDRV_PCM_HW_PARAM_FORMAT,
1089 					  SNDRV_PCM_HW_PARAM_CHANNELS,
1090 					  SNDRV_PCM_HW_PARAM_RATE,
1091 					  -1);
1092 		if (err < 0)
1093 			return err;
1094 	}
1095 
1096 	/* set max period and buffer sizes for 1 and 2 seconds, respectively */
1097 	err = snd_pcm_hw_constraint_minmax(runtime,
1098 					   SNDRV_PCM_HW_PARAM_PERIOD_TIME,
1099 					   0, 1000000);
1100 	if (err < 0)
1101 		return err;
1102 	err = snd_pcm_hw_constraint_minmax(runtime,
1103 					   SNDRV_PCM_HW_PARAM_BUFFER_TIME,
1104 					   0, 2000000);
1105 	if (err < 0)
1106 		return err;
1107 
1108 	/* additional hw constraints for implicit fb */
1109 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
1110 				  hw_rule_format_implicit_fb, subs,
1111 				  SNDRV_PCM_HW_PARAM_FORMAT, -1);
1112 	if (err < 0)
1113 		return err;
1114 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
1115 				  hw_rule_rate_implicit_fb, subs,
1116 				  SNDRV_PCM_HW_PARAM_RATE, -1);
1117 	if (err < 0)
1118 		return err;
1119 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
1120 				  hw_rule_period_size_implicit_fb, subs,
1121 				  SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
1122 	if (err < 0)
1123 		return err;
1124 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIODS,
1125 				  hw_rule_periods_implicit_fb, subs,
1126 				  SNDRV_PCM_HW_PARAM_PERIODS, -1);
1127 	if (err < 0)
1128 		return err;
1129 
1130 	return 0;
1131 }
1132 
snd_usb_pcm_open(struct snd_pcm_substream * substream)1133 static int snd_usb_pcm_open(struct snd_pcm_substream *substream)
1134 {
1135 	int direction = substream->stream;
1136 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1137 	struct snd_pcm_runtime *runtime = substream->runtime;
1138 	struct snd_usb_substream *subs = &as->substream[direction];
1139 	int ret;
1140 
1141 	runtime->hw = snd_usb_hardware;
1142 	/* need an explicit sync to catch applptr update in low-latency mode */
1143 	if (direction == SNDRV_PCM_STREAM_PLAYBACK &&
1144 	    as->chip->lowlatency)
1145 		runtime->hw.info |= SNDRV_PCM_INFO_SYNC_APPLPTR;
1146 	runtime->private_data = subs;
1147 	subs->pcm_substream = substream;
1148 	/* runtime PM is also done there */
1149 
1150 	/* initialize DSD/DOP context */
1151 	subs->dsd_dop.byte_idx = 0;
1152 	subs->dsd_dop.channel = 0;
1153 	subs->dsd_dop.marker = 1;
1154 
1155 	ret = setup_hw_info(runtime, subs);
1156 	if (ret < 0)
1157 		return ret;
1158 	ret = snd_usb_autoresume(subs->stream->chip);
1159 	if (ret < 0)
1160 		return ret;
1161 	ret = snd_media_stream_init(subs, as->pcm, direction);
1162 	if (ret < 0)
1163 		snd_usb_autosuspend(subs->stream->chip);
1164 	return ret;
1165 }
1166 
snd_usb_pcm_close(struct snd_pcm_substream * substream)1167 static int snd_usb_pcm_close(struct snd_pcm_substream *substream)
1168 {
1169 	int direction = substream->stream;
1170 	struct snd_usb_stream *as = snd_pcm_substream_chip(substream);
1171 	struct snd_usb_substream *subs = &as->substream[direction];
1172 	int ret;
1173 
1174 	snd_media_stop_pipeline(subs);
1175 
1176 	if (!snd_usb_lock_shutdown(subs->stream->chip)) {
1177 		ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D1);
1178 		snd_usb_unlock_shutdown(subs->stream->chip);
1179 		if (ret < 0)
1180 			return ret;
1181 	}
1182 
1183 	subs->pcm_substream = NULL;
1184 	snd_usb_autosuspend(subs->stream->chip);
1185 
1186 	return 0;
1187 }
1188 
1189 /* Since a URB can handle only a single linear buffer, we must use double
1190  * buffering when the data to be transferred overflows the buffer boundary.
1191  * To avoid inconsistencies when updating hwptr_done, we use double buffering
1192  * for all URBs.
1193  */
retire_capture_urb(struct snd_usb_substream * subs,struct urb * urb)1194 static void retire_capture_urb(struct snd_usb_substream *subs,
1195 			       struct urb *urb)
1196 {
1197 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1198 	unsigned int stride, frames, bytes, oldptr;
1199 	int i, period_elapsed = 0;
1200 	unsigned long flags;
1201 	unsigned char *cp;
1202 	int current_frame_number;
1203 
1204 	/* read frame number here, update pointer in critical section */
1205 	current_frame_number = usb_get_current_frame_number(subs->dev);
1206 
1207 	stride = runtime->frame_bits >> 3;
1208 
1209 	for (i = 0; i < urb->number_of_packets; i++) {
1210 		cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset + subs->pkt_offset_adj;
1211 		if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
1212 			dev_dbg(&subs->dev->dev, "frame %d active: %d\n",
1213 				i, urb->iso_frame_desc[i].status);
1214 			// continue;
1215 		}
1216 		bytes = urb->iso_frame_desc[i].actual_length;
1217 		if (subs->stream_offset_adj > 0) {
1218 			unsigned int adj = min(subs->stream_offset_adj, bytes);
1219 			cp += adj;
1220 			bytes -= adj;
1221 			subs->stream_offset_adj -= adj;
1222 		}
1223 		frames = bytes / stride;
1224 		if (!subs->txfr_quirk)
1225 			bytes = frames * stride;
1226 		if (bytes % (runtime->sample_bits >> 3) != 0) {
1227 			int oldbytes = bytes;
1228 			bytes = frames * stride;
1229 			dev_warn_ratelimited(&subs->dev->dev,
1230 				 "Corrected urb data len. %d->%d\n",
1231 							oldbytes, bytes);
1232 		}
1233 		/* update the current pointer */
1234 		spin_lock_irqsave(&subs->lock, flags);
1235 		oldptr = subs->hwptr_done;
1236 		subs->hwptr_done += bytes;
1237 		if (subs->hwptr_done >= subs->buffer_bytes)
1238 			subs->hwptr_done -= subs->buffer_bytes;
1239 		frames = (bytes + (oldptr % stride)) / stride;
1240 		subs->transfer_done += frames;
1241 		if (subs->transfer_done >= runtime->period_size) {
1242 			subs->transfer_done -= runtime->period_size;
1243 			period_elapsed = 1;
1244 		}
1245 
1246 		/* realign last_frame_number */
1247 		subs->last_frame_number = current_frame_number;
1248 
1249 		spin_unlock_irqrestore(&subs->lock, flags);
1250 		/* copy a data chunk */
1251 		if (oldptr + bytes > subs->buffer_bytes) {
1252 			unsigned int bytes1 = subs->buffer_bytes - oldptr;
1253 
1254 			memcpy(runtime->dma_area + oldptr, cp, bytes1);
1255 			memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
1256 		} else {
1257 			memcpy(runtime->dma_area + oldptr, cp, bytes);
1258 		}
1259 	}
1260 
1261 	if (period_elapsed)
1262 		snd_pcm_period_elapsed(subs->pcm_substream);
1263 }
1264 
urb_ctx_queue_advance(struct snd_usb_substream * subs,struct urb * urb,unsigned int bytes)1265 static void urb_ctx_queue_advance(struct snd_usb_substream *subs,
1266 				  struct urb *urb, unsigned int bytes)
1267 {
1268 	struct snd_urb_ctx *ctx = urb->context;
1269 
1270 	ctx->queued += bytes;
1271 	subs->inflight_bytes += bytes;
1272 	subs->hwptr_done += bytes;
1273 	if (subs->hwptr_done >= subs->buffer_bytes)
1274 		subs->hwptr_done -= subs->buffer_bytes;
1275 }
1276 
fill_playback_urb_dsd_dop(struct snd_usb_substream * subs,struct urb * urb,unsigned int bytes)1277 static inline void fill_playback_urb_dsd_dop(struct snd_usb_substream *subs,
1278 					     struct urb *urb, unsigned int bytes)
1279 {
1280 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1281 	unsigned int dst_idx = 0;
1282 	unsigned int src_idx = subs->hwptr_done;
1283 	unsigned int wrap = subs->buffer_bytes;
1284 	u8 *dst = urb->transfer_buffer;
1285 	u8 *src = runtime->dma_area;
1286 	u8 marker[] = { 0x05, 0xfa };
1287 	unsigned int queued = 0;
1288 
1289 	/*
1290 	 * The DSP DOP format defines a way to transport DSD samples over
1291 	 * normal PCM data endpoints. It requires stuffing of marker bytes
1292 	 * (0x05 and 0xfa, alternating per sample frame), and then expects
1293 	 * 2 additional bytes of actual payload. The whole frame is stored
1294 	 * LSB.
1295 	 *
1296 	 * Hence, for a stereo transport, the buffer layout looks like this,
1297 	 * where L refers to left channel samples and R to right.
1298 	 *
1299 	 *   L1 L2 0x05   R1 R2 0x05   L3 L4 0xfa  R3 R4 0xfa
1300 	 *   L5 L6 0x05   R5 R6 0x05   L7 L8 0xfa  R7 R8 0xfa
1301 	 *   .....
1302 	 *
1303 	 */
1304 
1305 	while (bytes--) {
1306 		if (++subs->dsd_dop.byte_idx == 3) {
1307 			/* frame boundary? */
1308 			dst[dst_idx++] = marker[subs->dsd_dop.marker];
1309 			src_idx += 2;
1310 			subs->dsd_dop.byte_idx = 0;
1311 
1312 			if (++subs->dsd_dop.channel % runtime->channels == 0) {
1313 				/* alternate the marker */
1314 				subs->dsd_dop.marker++;
1315 				subs->dsd_dop.marker %= ARRAY_SIZE(marker);
1316 				subs->dsd_dop.channel = 0;
1317 			}
1318 		} else {
1319 			/* stuff the DSD payload */
1320 			int idx = (src_idx + subs->dsd_dop.byte_idx - 1) % wrap;
1321 
1322 			if (subs->cur_audiofmt->dsd_bitrev)
1323 				dst[dst_idx++] = bitrev8(src[idx]);
1324 			else
1325 				dst[dst_idx++] = src[idx];
1326 			queued++;
1327 		}
1328 	}
1329 
1330 	urb_ctx_queue_advance(subs, urb, queued);
1331 }
1332 
1333 /* copy bit-reversed bytes onto transfer buffer */
fill_playback_urb_dsd_bitrev(struct snd_usb_substream * subs,struct urb * urb,unsigned int bytes)1334 static void fill_playback_urb_dsd_bitrev(struct snd_usb_substream *subs,
1335 					 struct urb *urb, unsigned int bytes)
1336 {
1337 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1338 	const u8 *src = runtime->dma_area;
1339 	u8 *buf = urb->transfer_buffer;
1340 	int i, ofs = subs->hwptr_done;
1341 
1342 	for (i = 0; i < bytes; i++) {
1343 		*buf++ = bitrev8(src[ofs]);
1344 		if (++ofs >= subs->buffer_bytes)
1345 			ofs = 0;
1346 	}
1347 
1348 	urb_ctx_queue_advance(subs, urb, bytes);
1349 }
1350 
copy_to_urb(struct snd_usb_substream * subs,struct urb * urb,int offset,int stride,unsigned int bytes)1351 static void copy_to_urb(struct snd_usb_substream *subs, struct urb *urb,
1352 			int offset, int stride, unsigned int bytes)
1353 {
1354 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1355 
1356 	if (subs->hwptr_done + bytes > subs->buffer_bytes) {
1357 		/* err, the transferred area goes over buffer boundary. */
1358 		unsigned int bytes1 = subs->buffer_bytes - subs->hwptr_done;
1359 
1360 		memcpy(urb->transfer_buffer + offset,
1361 		       runtime->dma_area + subs->hwptr_done, bytes1);
1362 		memcpy(urb->transfer_buffer + offset + bytes1,
1363 		       runtime->dma_area, bytes - bytes1);
1364 	} else {
1365 		memcpy(urb->transfer_buffer + offset,
1366 		       runtime->dma_area + subs->hwptr_done, bytes);
1367 	}
1368 
1369 	urb_ctx_queue_advance(subs, urb, bytes);
1370 }
1371 
copy_to_urb_quirk(struct snd_usb_substream * subs,struct urb * urb,int stride,unsigned int bytes)1372 static unsigned int copy_to_urb_quirk(struct snd_usb_substream *subs,
1373 				      struct urb *urb, int stride,
1374 				      unsigned int bytes)
1375 {
1376 	__le32 packet_length;
1377 	int i;
1378 
1379 	/* Put __le32 length descriptor at start of each packet. */
1380 	for (i = 0; i < urb->number_of_packets; i++) {
1381 		unsigned int length = urb->iso_frame_desc[i].length;
1382 		unsigned int offset = urb->iso_frame_desc[i].offset;
1383 
1384 		packet_length = cpu_to_le32(length);
1385 		offset += i * sizeof(packet_length);
1386 		urb->iso_frame_desc[i].offset = offset;
1387 		urb->iso_frame_desc[i].length += sizeof(packet_length);
1388 		memcpy(urb->transfer_buffer + offset,
1389 		       &packet_length, sizeof(packet_length));
1390 		copy_to_urb(subs, urb, offset + sizeof(packet_length),
1391 			    stride, length);
1392 	}
1393 	/* Adjust transfer size accordingly. */
1394 	bytes += urb->number_of_packets * sizeof(packet_length);
1395 	return bytes;
1396 }
1397 
prepare_playback_urb(struct snd_usb_substream * subs,struct urb * urb,bool in_stream_lock)1398 static int prepare_playback_urb(struct snd_usb_substream *subs,
1399 				struct urb *urb,
1400 				bool in_stream_lock)
1401 {
1402 	struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
1403 	struct snd_usb_endpoint *ep = subs->data_endpoint;
1404 	struct snd_urb_ctx *ctx = urb->context;
1405 	unsigned int frames, bytes;
1406 	int counts;
1407 	unsigned int transfer_done, frame_limit, avail = 0;
1408 	int i, stride, period_elapsed = 0;
1409 	unsigned long flags;
1410 	int err = 0;
1411 
1412 	stride = ep->stride;
1413 
1414 	frames = 0;
1415 	ctx->queued = 0;
1416 	urb->number_of_packets = 0;
1417 
1418 	spin_lock_irqsave(&subs->lock, flags);
1419 	frame_limit = subs->frame_limit + ep->max_urb_frames;
1420 	transfer_done = subs->transfer_done;
1421 
1422 	if (subs->lowlatency_playback &&
1423 	    runtime->status->state != SNDRV_PCM_STATE_DRAINING) {
1424 		unsigned int hwptr = subs->hwptr_done / stride;
1425 
1426 		/* calculate the byte offset-in-buffer of the appl_ptr */
1427 		avail = (runtime->control->appl_ptr - runtime->hw_ptr_base)
1428 			% runtime->buffer_size;
1429 		if (avail <= hwptr)
1430 			avail += runtime->buffer_size;
1431 		avail -= hwptr;
1432 	}
1433 
1434 	for (i = 0; i < ctx->packets; i++) {
1435 		counts = snd_usb_endpoint_next_packet_size(ep, ctx, i, avail);
1436 		if (counts < 0)
1437 			break;
1438 		/* set up descriptor */
1439 		urb->iso_frame_desc[i].offset = frames * stride;
1440 		urb->iso_frame_desc[i].length = counts * stride;
1441 		frames += counts;
1442 		avail -= counts;
1443 		urb->number_of_packets++;
1444 		transfer_done += counts;
1445 		if (transfer_done >= runtime->period_size) {
1446 			transfer_done -= runtime->period_size;
1447 			frame_limit = 0;
1448 			period_elapsed = 1;
1449 			if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
1450 				if (transfer_done > 0) {
1451 					/* FIXME: fill-max mode is not
1452 					 * supported yet */
1453 					frames -= transfer_done;
1454 					counts -= transfer_done;
1455 					urb->iso_frame_desc[i].length =
1456 						counts * stride;
1457 					transfer_done = 0;
1458 				}
1459 				i++;
1460 				if (i < ctx->packets) {
1461 					/* add a transfer delimiter */
1462 					urb->iso_frame_desc[i].offset =
1463 						frames * stride;
1464 					urb->iso_frame_desc[i].length = 0;
1465 					urb->number_of_packets++;
1466 				}
1467 				break;
1468 			}
1469 		}
1470 		/* finish at the period boundary or after enough frames */
1471 		if ((period_elapsed || transfer_done >= frame_limit) &&
1472 		    !snd_usb_endpoint_implicit_feedback_sink(ep))
1473 			break;
1474 	}
1475 
1476 	if (!frames) {
1477 		err = -EAGAIN;
1478 		goto unlock;
1479 	}
1480 
1481 	bytes = frames * stride;
1482 	subs->transfer_done = transfer_done;
1483 	subs->frame_limit = frame_limit;
1484 	if (unlikely(ep->cur_format == SNDRV_PCM_FORMAT_DSD_U16_LE &&
1485 		     subs->cur_audiofmt->dsd_dop)) {
1486 		fill_playback_urb_dsd_dop(subs, urb, bytes);
1487 	} else if (unlikely(ep->cur_format == SNDRV_PCM_FORMAT_DSD_U8 &&
1488 			   subs->cur_audiofmt->dsd_bitrev)) {
1489 		fill_playback_urb_dsd_bitrev(subs, urb, bytes);
1490 	} else {
1491 		/* usual PCM */
1492 		if (!subs->tx_length_quirk)
1493 			copy_to_urb(subs, urb, 0, stride, bytes);
1494 		else
1495 			bytes = copy_to_urb_quirk(subs, urb, stride, bytes);
1496 			/* bytes is now amount of outgoing data */
1497 	}
1498 
1499 	subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1500 
1501 	if (subs->trigger_tstamp_pending_update) {
1502 		/* this is the first actual URB submitted,
1503 		 * update trigger timestamp to reflect actual start time
1504 		 */
1505 		snd_pcm_gettime(runtime, &runtime->trigger_tstamp);
1506 		subs->trigger_tstamp_pending_update = false;
1507 	}
1508 
1509 	if (period_elapsed && !subs->running && subs->lowlatency_playback) {
1510 		subs->period_elapsed_pending = 1;
1511 		period_elapsed = 0;
1512 	}
1513 
1514  unlock:
1515 	spin_unlock_irqrestore(&subs->lock, flags);
1516 	if (err < 0)
1517 		return err;
1518 	urb->transfer_buffer_length = bytes;
1519 	if (period_elapsed) {
1520 		if (in_stream_lock)
1521 			snd_pcm_period_elapsed_under_stream_lock(subs->pcm_substream);
1522 		else
1523 			snd_pcm_period_elapsed(subs->pcm_substream);
1524 	}
1525 	return 0;
1526 }
1527 
1528 /*
1529  * process after playback data complete
1530  * - decrease the delay count again
1531  */
retire_playback_urb(struct snd_usb_substream * subs,struct urb * urb)1532 static void retire_playback_urb(struct snd_usb_substream *subs,
1533 			       struct urb *urb)
1534 {
1535 	unsigned long flags;
1536 	struct snd_urb_ctx *ctx = urb->context;
1537 	bool period_elapsed = false;
1538 
1539 	spin_lock_irqsave(&subs->lock, flags);
1540 	if (ctx->queued) {
1541 		if (subs->inflight_bytes >= ctx->queued)
1542 			subs->inflight_bytes -= ctx->queued;
1543 		else
1544 			subs->inflight_bytes = 0;
1545 	}
1546 
1547 	subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1548 	if (subs->running) {
1549 		period_elapsed = subs->period_elapsed_pending;
1550 		subs->period_elapsed_pending = 0;
1551 	}
1552 	spin_unlock_irqrestore(&subs->lock, flags);
1553 	if (period_elapsed)
1554 		snd_pcm_period_elapsed(subs->pcm_substream);
1555 }
1556 
1557 /* PCM ack callback for the playback stream;
1558  * this plays a role only when the stream is running in low-latency mode.
1559  */
snd_usb_pcm_playback_ack(struct snd_pcm_substream * substream)1560 static int snd_usb_pcm_playback_ack(struct snd_pcm_substream *substream)
1561 {
1562 	struct snd_usb_substream *subs = substream->runtime->private_data;
1563 	struct snd_usb_endpoint *ep;
1564 
1565 	if (!subs->lowlatency_playback || !subs->running)
1566 		return 0;
1567 	ep = subs->data_endpoint;
1568 	if (!ep)
1569 		return 0;
1570 	/* When no more in-flight URBs available, try to process the pending
1571 	 * outputs here
1572 	 */
1573 	if (!ep->active_mask)
1574 		return snd_usb_queue_pending_output_urbs(ep, true);
1575 	return 0;
1576 }
1577 
snd_usb_substream_playback_trigger(struct snd_pcm_substream * substream,int cmd)1578 static int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream,
1579 					      int cmd)
1580 {
1581 	struct snd_usb_substream *subs = substream->runtime->private_data;
1582 	int err;
1583 	bool suspend = true;
1584 
1585 	switch (cmd) {
1586 	case SNDRV_PCM_TRIGGER_START:
1587 		subs->trigger_tstamp_pending_update = true;
1588 		fallthrough;
1589 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1590 		snd_usb_endpoint_set_callback(subs->data_endpoint,
1591 					      prepare_playback_urb,
1592 					      retire_playback_urb,
1593 					      subs);
1594 		if (subs->lowlatency_playback &&
1595 		    cmd == SNDRV_PCM_TRIGGER_START) {
1596 			if (in_free_wheeling_mode(substream->runtime))
1597 				subs->lowlatency_playback = false;
1598 			err = start_endpoints(subs);
1599 			if (err < 0) {
1600 				snd_usb_endpoint_set_callback(subs->data_endpoint,
1601 							      NULL, NULL, NULL);
1602 				return err;
1603 			}
1604 		}
1605 		subs->running = 1;
1606 		dev_dbg(&subs->dev->dev, "%d:%d Start Playback PCM\n",
1607 			subs->cur_audiofmt->iface,
1608 			subs->cur_audiofmt->altsetting);
1609 		return 0;
1610 	case SNDRV_PCM_TRIGGER_SUSPEND:
1611 		trace_android_vh_audio_usb_offload_suspend(substream, cmd, &suspend);
1612 		if (!suspend)
1613 			return 0;
1614 		fallthrough;
1615 	case SNDRV_PCM_TRIGGER_STOP:
1616 		stop_endpoints(subs, substream->runtime->status->state == SNDRV_PCM_STATE_DRAINING);
1617 		snd_usb_endpoint_set_callback(subs->data_endpoint,
1618 					      NULL, NULL, NULL);
1619 		subs->running = 0;
1620 		dev_dbg(&subs->dev->dev, "%d:%d Stop Playback PCM\n",
1621 			subs->cur_audiofmt->iface,
1622 			subs->cur_audiofmt->altsetting);
1623 		return 0;
1624 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1625 		/* keep retire_data_urb for delay calculation */
1626 		snd_usb_endpoint_set_callback(subs->data_endpoint,
1627 					      NULL,
1628 					      retire_playback_urb,
1629 					      subs);
1630 		subs->running = 0;
1631 		dev_dbg(&subs->dev->dev, "%d:%d Pause Playback PCM\n",
1632 			subs->cur_audiofmt->iface,
1633 			subs->cur_audiofmt->altsetting);
1634 		return 0;
1635 	}
1636 
1637 	return -EINVAL;
1638 }
1639 
snd_usb_substream_capture_trigger(struct snd_pcm_substream * substream,int cmd)1640 static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream,
1641 					     int cmd)
1642 {
1643 	int err;
1644 	struct snd_usb_substream *subs = substream->runtime->private_data;
1645 
1646 	switch (cmd) {
1647 	case SNDRV_PCM_TRIGGER_START:
1648 		err = start_endpoints(subs);
1649 		if (err < 0)
1650 			return err;
1651 		fallthrough;
1652 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
1653 		snd_usb_endpoint_set_callback(subs->data_endpoint,
1654 					      NULL, retire_capture_urb,
1655 					      subs);
1656 		subs->last_frame_number = usb_get_current_frame_number(subs->dev);
1657 		subs->running = 1;
1658 		dev_dbg(&subs->dev->dev, "%d:%d Start Capture PCM\n",
1659 			subs->cur_audiofmt->iface,
1660 			subs->cur_audiofmt->altsetting);
1661 		return 0;
1662 	case SNDRV_PCM_TRIGGER_SUSPEND:
1663 	case SNDRV_PCM_TRIGGER_STOP:
1664 		stop_endpoints(subs, false);
1665 		fallthrough;
1666 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
1667 		snd_usb_endpoint_set_callback(subs->data_endpoint,
1668 					      NULL, NULL, NULL);
1669 		subs->running = 0;
1670 		dev_dbg(&subs->dev->dev, "%d:%d Stop Capture PCM\n",
1671 			subs->cur_audiofmt->iface,
1672 			subs->cur_audiofmt->altsetting);
1673 		return 0;
1674 	}
1675 
1676 	return -EINVAL;
1677 }
1678 
1679 static const struct snd_pcm_ops snd_usb_playback_ops = {
1680 	.open =		snd_usb_pcm_open,
1681 	.close =	snd_usb_pcm_close,
1682 	.hw_params =	snd_usb_hw_params,
1683 	.hw_free =	snd_usb_hw_free,
1684 	.prepare =	snd_usb_pcm_prepare,
1685 	.trigger =	snd_usb_substream_playback_trigger,
1686 	.sync_stop =	snd_usb_pcm_sync_stop,
1687 	.pointer =	snd_usb_pcm_pointer,
1688 	.ack =		snd_usb_pcm_playback_ack,
1689 };
1690 
1691 static const struct snd_pcm_ops snd_usb_capture_ops = {
1692 	.open =		snd_usb_pcm_open,
1693 	.close =	snd_usb_pcm_close,
1694 	.hw_params =	snd_usb_hw_params,
1695 	.hw_free =	snd_usb_hw_free,
1696 	.prepare =	snd_usb_pcm_prepare,
1697 	.trigger =	snd_usb_substream_capture_trigger,
1698 	.sync_stop =	snd_usb_pcm_sync_stop,
1699 	.pointer =	snd_usb_pcm_pointer,
1700 };
1701 
snd_usb_set_pcm_ops(struct snd_pcm * pcm,int stream)1702 void snd_usb_set_pcm_ops(struct snd_pcm *pcm, int stream)
1703 {
1704 	const struct snd_pcm_ops *ops;
1705 
1706 	ops = stream == SNDRV_PCM_STREAM_PLAYBACK ?
1707 			&snd_usb_playback_ops : &snd_usb_capture_ops;
1708 	snd_pcm_set_ops(pcm, stream, ops);
1709 }
1710 
snd_usb_preallocate_buffer(struct snd_usb_substream * subs)1711 void snd_usb_preallocate_buffer(struct snd_usb_substream *subs)
1712 {
1713 	struct snd_pcm *pcm = subs->stream->pcm;
1714 	struct snd_pcm_substream *s = pcm->streams[subs->direction].substream;
1715 	struct device *dev = subs->dev->bus->sysdev;
1716 
1717 	if (snd_usb_use_vmalloc)
1718 		snd_pcm_set_managed_buffer(s, SNDRV_DMA_TYPE_VMALLOC,
1719 					   NULL, 0, 0);
1720 	else
1721 		snd_pcm_set_managed_buffer(s, SNDRV_DMA_TYPE_DEV_SG,
1722 					   dev, 64*1024, 512*1024);
1723 }
1724