xref: /openbmc/linux/sound/soc/soc-pcm.c (revision bb0eb050)
1 /*
2  * soc-pcm.c  --  ALSA SoC PCM
3  *
4  * Copyright 2005 Wolfson Microelectronics PLC.
5  * Copyright 2005 Openedhand Ltd.
6  * Copyright (C) 2010 Slimlogic Ltd.
7  * Copyright (C) 2010 Texas Instruments Inc.
8  *
9  * Authors: Liam Girdwood <lrg@ti.com>
10  *          Mark Brown <broonie@opensource.wolfsonmicro.com>
11  *
12  *  This program is free software; you can redistribute  it and/or modify it
13  *  under  the terms of  the GNU General  Public License as published by the
14  *  Free Software Foundation;  either version 2 of the  License, or (at your
15  *  option) any later version.
16  *
17  */
18 
19 #include <linux/kernel.h>
20 #include <linux/init.h>
21 #include <linux/delay.h>
22 #include <linux/pinctrl/consumer.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/slab.h>
25 #include <linux/workqueue.h>
26 #include <linux/export.h>
27 #include <linux/debugfs.h>
28 #include <sound/core.h>
29 #include <sound/pcm.h>
30 #include <sound/pcm_params.h>
31 #include <sound/soc.h>
32 #include <sound/soc-dpcm.h>
33 #include <sound/initval.h>
34 
35 #define DPCM_MAX_BE_USERS	8
36 
37 /*
38  * snd_soc_dai_stream_valid() - check if a DAI supports the given stream
39  *
40  * Returns true if the DAI supports the indicated stream type.
41  */
42 static bool snd_soc_dai_stream_valid(struct snd_soc_dai *dai, int stream)
43 {
44 	struct snd_soc_pcm_stream *codec_stream;
45 
46 	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
47 		codec_stream = &dai->driver->playback;
48 	else
49 		codec_stream = &dai->driver->capture;
50 
51 	/* If the codec specifies any rate at all, it supports the stream. */
52 	return codec_stream->rates;
53 }
54 
55 /**
56  * snd_soc_runtime_activate() - Increment active count for PCM runtime components
57  * @rtd: ASoC PCM runtime that is activated
58  * @stream: Direction of the PCM stream
59  *
60  * Increments the active count for all the DAIs and components attached to a PCM
61  * runtime. Should typically be called when a stream is opened.
62  *
63  * Must be called with the rtd->pcm_mutex being held
64  */
65 void snd_soc_runtime_activate(struct snd_soc_pcm_runtime *rtd, int stream)
66 {
67 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
68 	int i;
69 
70 	lockdep_assert_held(&rtd->pcm_mutex);
71 
72 	if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
73 		cpu_dai->playback_active++;
74 		for (i = 0; i < rtd->num_codecs; i++)
75 			rtd->codec_dais[i]->playback_active++;
76 	} else {
77 		cpu_dai->capture_active++;
78 		for (i = 0; i < rtd->num_codecs; i++)
79 			rtd->codec_dais[i]->capture_active++;
80 	}
81 
82 	cpu_dai->active++;
83 	cpu_dai->component->active++;
84 	for (i = 0; i < rtd->num_codecs; i++) {
85 		rtd->codec_dais[i]->active++;
86 		rtd->codec_dais[i]->component->active++;
87 	}
88 }
89 
90 /**
91  * snd_soc_runtime_deactivate() - Decrement active count for PCM runtime components
92  * @rtd: ASoC PCM runtime that is deactivated
93  * @stream: Direction of the PCM stream
94  *
95  * Decrements the active count for all the DAIs and components attached to a PCM
96  * runtime. Should typically be called when a stream is closed.
97  *
98  * Must be called with the rtd->pcm_mutex being held
99  */
100 void snd_soc_runtime_deactivate(struct snd_soc_pcm_runtime *rtd, int stream)
101 {
102 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
103 	int i;
104 
105 	lockdep_assert_held(&rtd->pcm_mutex);
106 
107 	if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
108 		cpu_dai->playback_active--;
109 		for (i = 0; i < rtd->num_codecs; i++)
110 			rtd->codec_dais[i]->playback_active--;
111 	} else {
112 		cpu_dai->capture_active--;
113 		for (i = 0; i < rtd->num_codecs; i++)
114 			rtd->codec_dais[i]->capture_active--;
115 	}
116 
117 	cpu_dai->active--;
118 	cpu_dai->component->active--;
119 	for (i = 0; i < rtd->num_codecs; i++) {
120 		rtd->codec_dais[i]->component->active--;
121 		rtd->codec_dais[i]->active--;
122 	}
123 }
124 
125 /**
126  * snd_soc_runtime_ignore_pmdown_time() - Check whether to ignore the power down delay
127  * @rtd: The ASoC PCM runtime that should be checked.
128  *
129  * This function checks whether the power down delay should be ignored for a
130  * specific PCM runtime. Returns true if the delay is 0, if it the DAI link has
131  * been configured to ignore the delay, or if none of the components benefits
132  * from having the delay.
133  */
134 bool snd_soc_runtime_ignore_pmdown_time(struct snd_soc_pcm_runtime *rtd)
135 {
136 	int i;
137 	bool ignore = true;
138 
139 	if (!rtd->pmdown_time || rtd->dai_link->ignore_pmdown_time)
140 		return true;
141 
142 	for (i = 0; i < rtd->num_codecs; i++)
143 		ignore &= rtd->codec_dais[i]->component->ignore_pmdown_time;
144 
145 	return rtd->cpu_dai->component->ignore_pmdown_time && ignore;
146 }
147 
148 /**
149  * snd_soc_set_runtime_hwparams - set the runtime hardware parameters
150  * @substream: the pcm substream
151  * @hw: the hardware parameters
152  *
153  * Sets the substream runtime hardware parameters.
154  */
155 int snd_soc_set_runtime_hwparams(struct snd_pcm_substream *substream,
156 	const struct snd_pcm_hardware *hw)
157 {
158 	struct snd_pcm_runtime *runtime = substream->runtime;
159 	runtime->hw.info = hw->info;
160 	runtime->hw.formats = hw->formats;
161 	runtime->hw.period_bytes_min = hw->period_bytes_min;
162 	runtime->hw.period_bytes_max = hw->period_bytes_max;
163 	runtime->hw.periods_min = hw->periods_min;
164 	runtime->hw.periods_max = hw->periods_max;
165 	runtime->hw.buffer_bytes_max = hw->buffer_bytes_max;
166 	runtime->hw.fifo_size = hw->fifo_size;
167 	return 0;
168 }
169 EXPORT_SYMBOL_GPL(snd_soc_set_runtime_hwparams);
170 
171 /* DPCM stream event, send event to FE and all active BEs. */
172 int dpcm_dapm_stream_event(struct snd_soc_pcm_runtime *fe, int dir,
173 	int event)
174 {
175 	struct snd_soc_dpcm *dpcm;
176 
177 	list_for_each_entry(dpcm, &fe->dpcm[dir].be_clients, list_be) {
178 
179 		struct snd_soc_pcm_runtime *be = dpcm->be;
180 
181 		dev_dbg(be->dev, "ASoC: BE %s event %d dir %d\n",
182 				be->dai_link->name, event, dir);
183 
184 		snd_soc_dapm_stream_event(be, dir, event);
185 	}
186 
187 	snd_soc_dapm_stream_event(fe, dir, event);
188 
189 	return 0;
190 }
191 
192 static int soc_pcm_apply_symmetry(struct snd_pcm_substream *substream,
193 					struct snd_soc_dai *soc_dai)
194 {
195 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
196 	int ret;
197 
198 	if (soc_dai->rate && (soc_dai->driver->symmetric_rates ||
199 				rtd->dai_link->symmetric_rates)) {
200 		dev_dbg(soc_dai->dev, "ASoC: Symmetry forces %dHz rate\n",
201 				soc_dai->rate);
202 
203 		ret = snd_pcm_hw_constraint_single(substream->runtime,
204 						SNDRV_PCM_HW_PARAM_RATE,
205 						soc_dai->rate);
206 		if (ret < 0) {
207 			dev_err(soc_dai->dev,
208 				"ASoC: Unable to apply rate constraint: %d\n",
209 				ret);
210 			return ret;
211 		}
212 	}
213 
214 	if (soc_dai->channels && (soc_dai->driver->symmetric_channels ||
215 				rtd->dai_link->symmetric_channels)) {
216 		dev_dbg(soc_dai->dev, "ASoC: Symmetry forces %d channel(s)\n",
217 				soc_dai->channels);
218 
219 		ret = snd_pcm_hw_constraint_single(substream->runtime,
220 						SNDRV_PCM_HW_PARAM_CHANNELS,
221 						soc_dai->channels);
222 		if (ret < 0) {
223 			dev_err(soc_dai->dev,
224 				"ASoC: Unable to apply channel symmetry constraint: %d\n",
225 				ret);
226 			return ret;
227 		}
228 	}
229 
230 	if (soc_dai->sample_bits && (soc_dai->driver->symmetric_samplebits ||
231 				rtd->dai_link->symmetric_samplebits)) {
232 		dev_dbg(soc_dai->dev, "ASoC: Symmetry forces %d sample bits\n",
233 				soc_dai->sample_bits);
234 
235 		ret = snd_pcm_hw_constraint_single(substream->runtime,
236 						SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
237 						soc_dai->sample_bits);
238 		if (ret < 0) {
239 			dev_err(soc_dai->dev,
240 				"ASoC: Unable to apply sample bits symmetry constraint: %d\n",
241 				ret);
242 			return ret;
243 		}
244 	}
245 
246 	return 0;
247 }
248 
249 static int soc_pcm_params_symmetry(struct snd_pcm_substream *substream,
250 				struct snd_pcm_hw_params *params)
251 {
252 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
253 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
254 	unsigned int rate, channels, sample_bits, symmetry, i;
255 
256 	rate = params_rate(params);
257 	channels = params_channels(params);
258 	sample_bits = snd_pcm_format_physical_width(params_format(params));
259 
260 	/* reject unmatched parameters when applying symmetry */
261 	symmetry = cpu_dai->driver->symmetric_rates ||
262 		rtd->dai_link->symmetric_rates;
263 
264 	for (i = 0; i < rtd->num_codecs; i++)
265 		symmetry |= rtd->codec_dais[i]->driver->symmetric_rates;
266 
267 	if (symmetry && cpu_dai->rate && cpu_dai->rate != rate) {
268 		dev_err(rtd->dev, "ASoC: unmatched rate symmetry: %d - %d\n",
269 				cpu_dai->rate, rate);
270 		return -EINVAL;
271 	}
272 
273 	symmetry = cpu_dai->driver->symmetric_channels ||
274 		rtd->dai_link->symmetric_channels;
275 
276 	for (i = 0; i < rtd->num_codecs; i++)
277 		symmetry |= rtd->codec_dais[i]->driver->symmetric_channels;
278 
279 	if (symmetry && cpu_dai->channels && cpu_dai->channels != channels) {
280 		dev_err(rtd->dev, "ASoC: unmatched channel symmetry: %d - %d\n",
281 				cpu_dai->channels, channels);
282 		return -EINVAL;
283 	}
284 
285 	symmetry = cpu_dai->driver->symmetric_samplebits ||
286 		rtd->dai_link->symmetric_samplebits;
287 
288 	for (i = 0; i < rtd->num_codecs; i++)
289 		symmetry |= rtd->codec_dais[i]->driver->symmetric_samplebits;
290 
291 	if (symmetry && cpu_dai->sample_bits && cpu_dai->sample_bits != sample_bits) {
292 		dev_err(rtd->dev, "ASoC: unmatched sample bits symmetry: %d - %d\n",
293 				cpu_dai->sample_bits, sample_bits);
294 		return -EINVAL;
295 	}
296 
297 	return 0;
298 }
299 
300 static bool soc_pcm_has_symmetry(struct snd_pcm_substream *substream)
301 {
302 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
303 	struct snd_soc_dai_driver *cpu_driver = rtd->cpu_dai->driver;
304 	struct snd_soc_dai_link *link = rtd->dai_link;
305 	unsigned int symmetry, i;
306 
307 	symmetry = cpu_driver->symmetric_rates || link->symmetric_rates ||
308 		cpu_driver->symmetric_channels || link->symmetric_channels ||
309 		cpu_driver->symmetric_samplebits || link->symmetric_samplebits;
310 
311 	for (i = 0; i < rtd->num_codecs; i++)
312 		symmetry = symmetry ||
313 			rtd->codec_dais[i]->driver->symmetric_rates ||
314 			rtd->codec_dais[i]->driver->symmetric_channels ||
315 			rtd->codec_dais[i]->driver->symmetric_samplebits;
316 
317 	return symmetry;
318 }
319 
320 static void soc_pcm_set_msb(struct snd_pcm_substream *substream, int bits)
321 {
322 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
323 	int ret;
324 
325 	if (!bits)
326 		return;
327 
328 	ret = snd_pcm_hw_constraint_msbits(substream->runtime, 0, 0, bits);
329 	if (ret != 0)
330 		dev_warn(rtd->dev, "ASoC: Failed to set MSB %d: %d\n",
331 				 bits, ret);
332 }
333 
334 static void soc_pcm_apply_msb(struct snd_pcm_substream *substream)
335 {
336 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
337 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
338 	struct snd_soc_dai *codec_dai;
339 	int i;
340 	unsigned int bits = 0, cpu_bits;
341 
342 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
343 		for (i = 0; i < rtd->num_codecs; i++) {
344 			codec_dai = rtd->codec_dais[i];
345 			if (codec_dai->driver->playback.sig_bits == 0) {
346 				bits = 0;
347 				break;
348 			}
349 			bits = max(codec_dai->driver->playback.sig_bits, bits);
350 		}
351 		cpu_bits = cpu_dai->driver->playback.sig_bits;
352 	} else {
353 		for (i = 0; i < rtd->num_codecs; i++) {
354 			codec_dai = rtd->codec_dais[i];
355 			if (codec_dai->driver->capture.sig_bits == 0) {
356 				bits = 0;
357 				break;
358 			}
359 			bits = max(codec_dai->driver->capture.sig_bits, bits);
360 		}
361 		cpu_bits = cpu_dai->driver->capture.sig_bits;
362 	}
363 
364 	soc_pcm_set_msb(substream, bits);
365 	soc_pcm_set_msb(substream, cpu_bits);
366 }
367 
368 static void soc_pcm_init_runtime_hw(struct snd_pcm_substream *substream)
369 {
370 	struct snd_pcm_runtime *runtime = substream->runtime;
371 	struct snd_pcm_hardware *hw = &runtime->hw;
372 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
373 	struct snd_soc_dai_driver *cpu_dai_drv = rtd->cpu_dai->driver;
374 	struct snd_soc_dai_driver *codec_dai_drv;
375 	struct snd_soc_pcm_stream *codec_stream;
376 	struct snd_soc_pcm_stream *cpu_stream;
377 	unsigned int chan_min = 0, chan_max = UINT_MAX;
378 	unsigned int rate_min = 0, rate_max = UINT_MAX;
379 	unsigned int rates = UINT_MAX;
380 	u64 formats = ULLONG_MAX;
381 	int i;
382 
383 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
384 		cpu_stream = &cpu_dai_drv->playback;
385 	else
386 		cpu_stream = &cpu_dai_drv->capture;
387 
388 	/* first calculate min/max only for CODECs in the DAI link */
389 	for (i = 0; i < rtd->num_codecs; i++) {
390 
391 		/*
392 		 * Skip CODECs which don't support the current stream type.
393 		 * Otherwise, since the rate, channel, and format values will
394 		 * zero in that case, we would have no usable settings left,
395 		 * causing the resulting setup to fail.
396 		 * At least one CODEC should match, otherwise we should have
397 		 * bailed out on a higher level, since there would be no
398 		 * CODEC to support the transfer direction in that case.
399 		 */
400 		if (!snd_soc_dai_stream_valid(rtd->codec_dais[i],
401 					      substream->stream))
402 			continue;
403 
404 		codec_dai_drv = rtd->codec_dais[i]->driver;
405 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
406 			codec_stream = &codec_dai_drv->playback;
407 		else
408 			codec_stream = &codec_dai_drv->capture;
409 		chan_min = max(chan_min, codec_stream->channels_min);
410 		chan_max = min(chan_max, codec_stream->channels_max);
411 		rate_min = max(rate_min, codec_stream->rate_min);
412 		rate_max = min_not_zero(rate_max, codec_stream->rate_max);
413 		formats &= codec_stream->formats;
414 		rates = snd_pcm_rate_mask_intersect(codec_stream->rates, rates);
415 	}
416 
417 	/*
418 	 * chan min/max cannot be enforced if there are multiple CODEC DAIs
419 	 * connected to a single CPU DAI, use CPU DAI's directly and let
420 	 * channel allocation be fixed up later
421 	 */
422 	if (rtd->num_codecs > 1) {
423 		chan_min = cpu_stream->channels_min;
424 		chan_max = cpu_stream->channels_max;
425 	}
426 
427 	hw->channels_min = max(chan_min, cpu_stream->channels_min);
428 	hw->channels_max = min(chan_max, cpu_stream->channels_max);
429 	if (hw->formats)
430 		hw->formats &= formats & cpu_stream->formats;
431 	else
432 		hw->formats = formats & cpu_stream->formats;
433 	hw->rates = snd_pcm_rate_mask_intersect(rates, cpu_stream->rates);
434 
435 	snd_pcm_limit_hw_rates(runtime);
436 
437 	hw->rate_min = max(hw->rate_min, cpu_stream->rate_min);
438 	hw->rate_min = max(hw->rate_min, rate_min);
439 	hw->rate_max = min_not_zero(hw->rate_max, cpu_stream->rate_max);
440 	hw->rate_max = min_not_zero(hw->rate_max, rate_max);
441 }
442 
443 /*
444  * Called by ALSA when a PCM substream is opened, the runtime->hw record is
445  * then initialized and any private data can be allocated. This also calls
446  * startup for the cpu DAI, platform, machine and codec DAI.
447  */
448 static int soc_pcm_open(struct snd_pcm_substream *substream)
449 {
450 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
451 	struct snd_pcm_runtime *runtime = substream->runtime;
452 	struct snd_soc_platform *platform = rtd->platform;
453 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
454 	struct snd_soc_dai *codec_dai;
455 	const char *codec_dai_name = "multicodec";
456 	int i, ret = 0;
457 
458 	pinctrl_pm_select_default_state(cpu_dai->dev);
459 	for (i = 0; i < rtd->num_codecs; i++)
460 		pinctrl_pm_select_default_state(rtd->codec_dais[i]->dev);
461 	pm_runtime_get_sync(cpu_dai->dev);
462 	for (i = 0; i < rtd->num_codecs; i++)
463 		pm_runtime_get_sync(rtd->codec_dais[i]->dev);
464 	pm_runtime_get_sync(platform->dev);
465 
466 	mutex_lock_nested(&rtd->pcm_mutex, rtd->pcm_subclass);
467 
468 	/* startup the audio subsystem */
469 	if (cpu_dai->driver->ops && cpu_dai->driver->ops->startup) {
470 		ret = cpu_dai->driver->ops->startup(substream, cpu_dai);
471 		if (ret < 0) {
472 			dev_err(cpu_dai->dev, "ASoC: can't open interface"
473 				" %s: %d\n", cpu_dai->name, ret);
474 			goto out;
475 		}
476 	}
477 
478 	if (platform->driver->ops && platform->driver->ops->open) {
479 		ret = platform->driver->ops->open(substream);
480 		if (ret < 0) {
481 			dev_err(platform->dev, "ASoC: can't open platform"
482 				" %s: %d\n", platform->component.name, ret);
483 			goto platform_err;
484 		}
485 	}
486 
487 	for (i = 0; i < rtd->num_codecs; i++) {
488 		codec_dai = rtd->codec_dais[i];
489 		if (codec_dai->driver->ops && codec_dai->driver->ops->startup) {
490 			ret = codec_dai->driver->ops->startup(substream,
491 							      codec_dai);
492 			if (ret < 0) {
493 				dev_err(codec_dai->dev,
494 					"ASoC: can't open codec %s: %d\n",
495 					codec_dai->name, ret);
496 				goto codec_dai_err;
497 			}
498 		}
499 
500 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
501 			codec_dai->tx_mask = 0;
502 		else
503 			codec_dai->rx_mask = 0;
504 	}
505 
506 	if (rtd->dai_link->ops && rtd->dai_link->ops->startup) {
507 		ret = rtd->dai_link->ops->startup(substream);
508 		if (ret < 0) {
509 			pr_err("ASoC: %s startup failed: %d\n",
510 			       rtd->dai_link->name, ret);
511 			goto machine_err;
512 		}
513 	}
514 
515 	/* Dynamic PCM DAI links compat checks use dynamic capabilities */
516 	if (rtd->dai_link->dynamic || rtd->dai_link->no_pcm)
517 		goto dynamic;
518 
519 	/* Check that the codec and cpu DAIs are compatible */
520 	soc_pcm_init_runtime_hw(substream);
521 
522 	if (rtd->num_codecs == 1)
523 		codec_dai_name = rtd->codec_dai->name;
524 
525 	if (soc_pcm_has_symmetry(substream))
526 		runtime->hw.info |= SNDRV_PCM_INFO_JOINT_DUPLEX;
527 
528 	ret = -EINVAL;
529 	if (!runtime->hw.rates) {
530 		printk(KERN_ERR "ASoC: %s <-> %s No matching rates\n",
531 			codec_dai_name, cpu_dai->name);
532 		goto config_err;
533 	}
534 	if (!runtime->hw.formats) {
535 		printk(KERN_ERR "ASoC: %s <-> %s No matching formats\n",
536 			codec_dai_name, cpu_dai->name);
537 		goto config_err;
538 	}
539 	if (!runtime->hw.channels_min || !runtime->hw.channels_max ||
540 	    runtime->hw.channels_min > runtime->hw.channels_max) {
541 		printk(KERN_ERR "ASoC: %s <-> %s No matching channels\n",
542 				codec_dai_name, cpu_dai->name);
543 		goto config_err;
544 	}
545 
546 	soc_pcm_apply_msb(substream);
547 
548 	/* Symmetry only applies if we've already got an active stream. */
549 	if (cpu_dai->active) {
550 		ret = soc_pcm_apply_symmetry(substream, cpu_dai);
551 		if (ret != 0)
552 			goto config_err;
553 	}
554 
555 	for (i = 0; i < rtd->num_codecs; i++) {
556 		if (rtd->codec_dais[i]->active) {
557 			ret = soc_pcm_apply_symmetry(substream,
558 						     rtd->codec_dais[i]);
559 			if (ret != 0)
560 				goto config_err;
561 		}
562 	}
563 
564 	pr_debug("ASoC: %s <-> %s info:\n",
565 			codec_dai_name, cpu_dai->name);
566 	pr_debug("ASoC: rate mask 0x%x\n", runtime->hw.rates);
567 	pr_debug("ASoC: min ch %d max ch %d\n", runtime->hw.channels_min,
568 		 runtime->hw.channels_max);
569 	pr_debug("ASoC: min rate %d max rate %d\n", runtime->hw.rate_min,
570 		 runtime->hw.rate_max);
571 
572 dynamic:
573 
574 	snd_soc_runtime_activate(rtd, substream->stream);
575 
576 	mutex_unlock(&rtd->pcm_mutex);
577 	return 0;
578 
579 config_err:
580 	if (rtd->dai_link->ops && rtd->dai_link->ops->shutdown)
581 		rtd->dai_link->ops->shutdown(substream);
582 
583 machine_err:
584 	i = rtd->num_codecs;
585 
586 codec_dai_err:
587 	while (--i >= 0) {
588 		codec_dai = rtd->codec_dais[i];
589 		if (codec_dai->driver->ops->shutdown)
590 			codec_dai->driver->ops->shutdown(substream, codec_dai);
591 	}
592 
593 	if (platform->driver->ops && platform->driver->ops->close)
594 		platform->driver->ops->close(substream);
595 
596 platform_err:
597 	if (cpu_dai->driver->ops->shutdown)
598 		cpu_dai->driver->ops->shutdown(substream, cpu_dai);
599 out:
600 	mutex_unlock(&rtd->pcm_mutex);
601 
602 	pm_runtime_mark_last_busy(platform->dev);
603 	pm_runtime_put_autosuspend(platform->dev);
604 	for (i = 0; i < rtd->num_codecs; i++) {
605 		pm_runtime_mark_last_busy(rtd->codec_dais[i]->dev);
606 		pm_runtime_put_autosuspend(rtd->codec_dais[i]->dev);
607 	}
608 
609 	pm_runtime_mark_last_busy(cpu_dai->dev);
610 	pm_runtime_put_autosuspend(cpu_dai->dev);
611 	for (i = 0; i < rtd->num_codecs; i++) {
612 		if (!rtd->codec_dais[i]->active)
613 			pinctrl_pm_select_sleep_state(rtd->codec_dais[i]->dev);
614 	}
615 	if (!cpu_dai->active)
616 		pinctrl_pm_select_sleep_state(cpu_dai->dev);
617 
618 	return ret;
619 }
620 
621 /*
622  * Power down the audio subsystem pmdown_time msecs after close is called.
623  * This is to ensure there are no pops or clicks in between any music tracks
624  * due to DAPM power cycling.
625  */
626 static void close_delayed_work(struct work_struct *work)
627 {
628 	struct snd_soc_pcm_runtime *rtd =
629 			container_of(work, struct snd_soc_pcm_runtime, delayed_work.work);
630 	struct snd_soc_dai *codec_dai = rtd->codec_dais[0];
631 
632 	mutex_lock_nested(&rtd->pcm_mutex, rtd->pcm_subclass);
633 
634 	dev_dbg(rtd->dev, "ASoC: pop wq checking: %s status: %s waiting: %s\n",
635 		 codec_dai->driver->playback.stream_name,
636 		 codec_dai->playback_active ? "active" : "inactive",
637 		 rtd->pop_wait ? "yes" : "no");
638 
639 	/* are we waiting on this codec DAI stream */
640 	if (rtd->pop_wait == 1) {
641 		rtd->pop_wait = 0;
642 		snd_soc_dapm_stream_event(rtd, SNDRV_PCM_STREAM_PLAYBACK,
643 					  SND_SOC_DAPM_STREAM_STOP);
644 	}
645 
646 	mutex_unlock(&rtd->pcm_mutex);
647 }
648 
649 /*
650  * Called by ALSA when a PCM substream is closed. Private data can be
651  * freed here. The cpu DAI, codec DAI, machine and platform are also
652  * shutdown.
653  */
654 static int soc_pcm_close(struct snd_pcm_substream *substream)
655 {
656 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
657 	struct snd_soc_platform *platform = rtd->platform;
658 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
659 	struct snd_soc_dai *codec_dai;
660 	int i;
661 
662 	mutex_lock_nested(&rtd->pcm_mutex, rtd->pcm_subclass);
663 
664 	snd_soc_runtime_deactivate(rtd, substream->stream);
665 
666 	/* clear the corresponding DAIs rate when inactive */
667 	if (!cpu_dai->active)
668 		cpu_dai->rate = 0;
669 
670 	for (i = 0; i < rtd->num_codecs; i++) {
671 		codec_dai = rtd->codec_dais[i];
672 		if (!codec_dai->active)
673 			codec_dai->rate = 0;
674 	}
675 
676 	snd_soc_dai_digital_mute(cpu_dai, 1, substream->stream);
677 
678 	if (cpu_dai->driver->ops->shutdown)
679 		cpu_dai->driver->ops->shutdown(substream, cpu_dai);
680 
681 	for (i = 0; i < rtd->num_codecs; i++) {
682 		codec_dai = rtd->codec_dais[i];
683 		if (codec_dai->driver->ops->shutdown)
684 			codec_dai->driver->ops->shutdown(substream, codec_dai);
685 	}
686 
687 	if (rtd->dai_link->ops && rtd->dai_link->ops->shutdown)
688 		rtd->dai_link->ops->shutdown(substream);
689 
690 	if (platform->driver->ops && platform->driver->ops->close)
691 		platform->driver->ops->close(substream);
692 
693 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
694 		if (snd_soc_runtime_ignore_pmdown_time(rtd)) {
695 			/* powered down playback stream now */
696 			snd_soc_dapm_stream_event(rtd,
697 						  SNDRV_PCM_STREAM_PLAYBACK,
698 						  SND_SOC_DAPM_STREAM_STOP);
699 		} else {
700 			/* start delayed pop wq here for playback streams */
701 			rtd->pop_wait = 1;
702 			queue_delayed_work(system_power_efficient_wq,
703 					   &rtd->delayed_work,
704 					   msecs_to_jiffies(rtd->pmdown_time));
705 		}
706 	} else {
707 		/* capture streams can be powered down now */
708 		snd_soc_dapm_stream_event(rtd, SNDRV_PCM_STREAM_CAPTURE,
709 					  SND_SOC_DAPM_STREAM_STOP);
710 	}
711 
712 	mutex_unlock(&rtd->pcm_mutex);
713 
714 	pm_runtime_mark_last_busy(platform->dev);
715 	pm_runtime_put_autosuspend(platform->dev);
716 
717 	for (i = 0; i < rtd->num_codecs; i++) {
718 		pm_runtime_mark_last_busy(rtd->codec_dais[i]->dev);
719 		pm_runtime_put_autosuspend(rtd->codec_dais[i]->dev);
720 	}
721 
722 	pm_runtime_mark_last_busy(cpu_dai->dev);
723 	pm_runtime_put_autosuspend(cpu_dai->dev);
724 
725 	for (i = 0; i < rtd->num_codecs; i++) {
726 		if (!rtd->codec_dais[i]->active)
727 			pinctrl_pm_select_sleep_state(rtd->codec_dais[i]->dev);
728 	}
729 	if (!cpu_dai->active)
730 		pinctrl_pm_select_sleep_state(cpu_dai->dev);
731 
732 	return 0;
733 }
734 
735 /*
736  * Called by ALSA when the PCM substream is prepared, can set format, sample
737  * rate, etc.  This function is non atomic and can be called multiple times,
738  * it can refer to the runtime info.
739  */
740 static int soc_pcm_prepare(struct snd_pcm_substream *substream)
741 {
742 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
743 	struct snd_soc_platform *platform = rtd->platform;
744 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
745 	struct snd_soc_dai *codec_dai;
746 	int i, ret = 0;
747 
748 	mutex_lock_nested(&rtd->pcm_mutex, rtd->pcm_subclass);
749 
750 	if (rtd->dai_link->ops && rtd->dai_link->ops->prepare) {
751 		ret = rtd->dai_link->ops->prepare(substream);
752 		if (ret < 0) {
753 			dev_err(rtd->card->dev, "ASoC: machine prepare error:"
754 				" %d\n", ret);
755 			goto out;
756 		}
757 	}
758 
759 	if (platform->driver->ops && platform->driver->ops->prepare) {
760 		ret = platform->driver->ops->prepare(substream);
761 		if (ret < 0) {
762 			dev_err(platform->dev, "ASoC: platform prepare error:"
763 				" %d\n", ret);
764 			goto out;
765 		}
766 	}
767 
768 	for (i = 0; i < rtd->num_codecs; i++) {
769 		codec_dai = rtd->codec_dais[i];
770 		if (codec_dai->driver->ops && codec_dai->driver->ops->prepare) {
771 			ret = codec_dai->driver->ops->prepare(substream,
772 							      codec_dai);
773 			if (ret < 0) {
774 				dev_err(codec_dai->dev,
775 					"ASoC: codec DAI prepare error: %d\n",
776 					ret);
777 				goto out;
778 			}
779 		}
780 	}
781 
782 	if (cpu_dai->driver->ops && cpu_dai->driver->ops->prepare) {
783 		ret = cpu_dai->driver->ops->prepare(substream, cpu_dai);
784 		if (ret < 0) {
785 			dev_err(cpu_dai->dev,
786 				"ASoC: cpu DAI prepare error: %d\n", ret);
787 			goto out;
788 		}
789 	}
790 
791 	/* cancel any delayed stream shutdown that is pending */
792 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
793 	    rtd->pop_wait) {
794 		rtd->pop_wait = 0;
795 		cancel_delayed_work(&rtd->delayed_work);
796 	}
797 
798 	snd_soc_dapm_stream_event(rtd, substream->stream,
799 			SND_SOC_DAPM_STREAM_START);
800 
801 	for (i = 0; i < rtd->num_codecs; i++)
802 		snd_soc_dai_digital_mute(rtd->codec_dais[i], 0,
803 					 substream->stream);
804 	snd_soc_dai_digital_mute(cpu_dai, 0, substream->stream);
805 
806 out:
807 	mutex_unlock(&rtd->pcm_mutex);
808 	return ret;
809 }
810 
811 static void soc_pcm_codec_params_fixup(struct snd_pcm_hw_params *params,
812 				       unsigned int mask)
813 {
814 	struct snd_interval *interval;
815 	int channels = hweight_long(mask);
816 
817 	interval = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
818 	interval->min = channels;
819 	interval->max = channels;
820 }
821 
822 int soc_dai_hw_params(struct snd_pcm_substream *substream,
823 		      struct snd_pcm_hw_params *params,
824 		      struct snd_soc_dai *dai)
825 {
826 	int ret;
827 
828 	if (dai->driver->ops && dai->driver->ops->hw_params) {
829 		ret = dai->driver->ops->hw_params(substream, params, dai);
830 		if (ret < 0) {
831 			dev_err(dai->dev, "ASoC: can't set %s hw params: %d\n",
832 				dai->name, ret);
833 			return ret;
834 		}
835 	}
836 
837 	return 0;
838 }
839 
840 /*
841  * Called by ALSA when the hardware params are set by application. This
842  * function can also be called multiple times and can allocate buffers
843  * (using snd_pcm_lib_* ). It's non-atomic.
844  */
845 static int soc_pcm_hw_params(struct snd_pcm_substream *substream,
846 				struct snd_pcm_hw_params *params)
847 {
848 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
849 	struct snd_soc_platform *platform = rtd->platform;
850 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
851 	int i, ret = 0;
852 
853 	mutex_lock_nested(&rtd->pcm_mutex, rtd->pcm_subclass);
854 
855 	ret = soc_pcm_params_symmetry(substream, params);
856 	if (ret)
857 		goto out;
858 
859 	if (rtd->dai_link->ops && rtd->dai_link->ops->hw_params) {
860 		ret = rtd->dai_link->ops->hw_params(substream, params);
861 		if (ret < 0) {
862 			dev_err(rtd->card->dev, "ASoC: machine hw_params"
863 				" failed: %d\n", ret);
864 			goto out;
865 		}
866 	}
867 
868 	for (i = 0; i < rtd->num_codecs; i++) {
869 		struct snd_soc_dai *codec_dai = rtd->codec_dais[i];
870 		struct snd_pcm_hw_params codec_params;
871 
872 		/*
873 		 * Skip CODECs which don't support the current stream type,
874 		 * the idea being that if a CODEC is not used for the currently
875 		 * set up transfer direction, it should not need to be
876 		 * configured, especially since the configuration used might
877 		 * not even be supported by that CODEC. There may be cases
878 		 * however where a CODEC needs to be set up although it is
879 		 * actually not being used for the transfer, e.g. if a
880 		 * capture-only CODEC is acting as an LRCLK and/or BCLK master
881 		 * for the DAI link including a playback-only CODEC.
882 		 * If this becomes necessary, we will have to augment the
883 		 * machine driver setup with information on how to act, so
884 		 * we can do the right thing here.
885 		 */
886 		if (!snd_soc_dai_stream_valid(codec_dai, substream->stream))
887 			continue;
888 
889 		/* copy params for each codec */
890 		codec_params = *params;
891 
892 		/* fixup params based on TDM slot masks */
893 		if (codec_dai->tx_mask)
894 			soc_pcm_codec_params_fixup(&codec_params,
895 						   codec_dai->tx_mask);
896 		if (codec_dai->rx_mask)
897 			soc_pcm_codec_params_fixup(&codec_params,
898 						   codec_dai->rx_mask);
899 
900 		ret = soc_dai_hw_params(substream, &codec_params, codec_dai);
901 		if(ret < 0)
902 			goto codec_err;
903 
904 		codec_dai->rate = params_rate(&codec_params);
905 		codec_dai->channels = params_channels(&codec_params);
906 		codec_dai->sample_bits = snd_pcm_format_physical_width(
907 						params_format(&codec_params));
908 	}
909 
910 	ret = soc_dai_hw_params(substream, params, cpu_dai);
911 	if (ret < 0)
912 		goto interface_err;
913 
914 	if (platform->driver->ops && platform->driver->ops->hw_params) {
915 		ret = platform->driver->ops->hw_params(substream, params);
916 		if (ret < 0) {
917 			dev_err(platform->dev, "ASoC: %s hw params failed: %d\n",
918 			       platform->component.name, ret);
919 			goto platform_err;
920 		}
921 	}
922 
923 	/* store the parameters for each DAIs */
924 	cpu_dai->rate = params_rate(params);
925 	cpu_dai->channels = params_channels(params);
926 	cpu_dai->sample_bits =
927 		snd_pcm_format_physical_width(params_format(params));
928 
929 out:
930 	mutex_unlock(&rtd->pcm_mutex);
931 	return ret;
932 
933 platform_err:
934 	if (cpu_dai->driver->ops && cpu_dai->driver->ops->hw_free)
935 		cpu_dai->driver->ops->hw_free(substream, cpu_dai);
936 
937 interface_err:
938 	i = rtd->num_codecs;
939 
940 codec_err:
941 	while (--i >= 0) {
942 		struct snd_soc_dai *codec_dai = rtd->codec_dais[i];
943 		if (codec_dai->driver->ops && codec_dai->driver->ops->hw_free)
944 			codec_dai->driver->ops->hw_free(substream, codec_dai);
945 		codec_dai->rate = 0;
946 	}
947 
948 	if (rtd->dai_link->ops && rtd->dai_link->ops->hw_free)
949 		rtd->dai_link->ops->hw_free(substream);
950 
951 	mutex_unlock(&rtd->pcm_mutex);
952 	return ret;
953 }
954 
955 /*
956  * Frees resources allocated by hw_params, can be called multiple times
957  */
958 static int soc_pcm_hw_free(struct snd_pcm_substream *substream)
959 {
960 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
961 	struct snd_soc_platform *platform = rtd->platform;
962 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
963 	struct snd_soc_dai *codec_dai;
964 	bool playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
965 	int i;
966 
967 	mutex_lock_nested(&rtd->pcm_mutex, rtd->pcm_subclass);
968 
969 	/* clear the corresponding DAIs parameters when going to be inactive */
970 	if (cpu_dai->active == 1) {
971 		cpu_dai->rate = 0;
972 		cpu_dai->channels = 0;
973 		cpu_dai->sample_bits = 0;
974 	}
975 
976 	for (i = 0; i < rtd->num_codecs; i++) {
977 		codec_dai = rtd->codec_dais[i];
978 		if (codec_dai->active == 1) {
979 			codec_dai->rate = 0;
980 			codec_dai->channels = 0;
981 			codec_dai->sample_bits = 0;
982 		}
983 	}
984 
985 	/* apply codec digital mute */
986 	for (i = 0; i < rtd->num_codecs; i++) {
987 		if ((playback && rtd->codec_dais[i]->playback_active == 1) ||
988 		    (!playback && rtd->codec_dais[i]->capture_active == 1))
989 			snd_soc_dai_digital_mute(rtd->codec_dais[i], 1,
990 						 substream->stream);
991 	}
992 
993 	/* free any machine hw params */
994 	if (rtd->dai_link->ops && rtd->dai_link->ops->hw_free)
995 		rtd->dai_link->ops->hw_free(substream);
996 
997 	/* free any DMA resources */
998 	if (platform->driver->ops && platform->driver->ops->hw_free)
999 		platform->driver->ops->hw_free(substream);
1000 
1001 	/* now free hw params for the DAIs  */
1002 	for (i = 0; i < rtd->num_codecs; i++) {
1003 		codec_dai = rtd->codec_dais[i];
1004 		if (codec_dai->driver->ops && codec_dai->driver->ops->hw_free)
1005 			codec_dai->driver->ops->hw_free(substream, codec_dai);
1006 	}
1007 
1008 	if (cpu_dai->driver->ops && cpu_dai->driver->ops->hw_free)
1009 		cpu_dai->driver->ops->hw_free(substream, cpu_dai);
1010 
1011 	mutex_unlock(&rtd->pcm_mutex);
1012 	return 0;
1013 }
1014 
1015 static int soc_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
1016 {
1017 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
1018 	struct snd_soc_platform *platform = rtd->platform;
1019 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
1020 	struct snd_soc_dai *codec_dai;
1021 	int i, ret;
1022 
1023 	for (i = 0; i < rtd->num_codecs; i++) {
1024 		codec_dai = rtd->codec_dais[i];
1025 		if (codec_dai->driver->ops && codec_dai->driver->ops->trigger) {
1026 			ret = codec_dai->driver->ops->trigger(substream,
1027 							      cmd, codec_dai);
1028 			if (ret < 0)
1029 				return ret;
1030 		}
1031 	}
1032 
1033 	if (platform->driver->ops && platform->driver->ops->trigger) {
1034 		ret = platform->driver->ops->trigger(substream, cmd);
1035 		if (ret < 0)
1036 			return ret;
1037 	}
1038 
1039 	if (cpu_dai->driver->ops && cpu_dai->driver->ops->trigger) {
1040 		ret = cpu_dai->driver->ops->trigger(substream, cmd, cpu_dai);
1041 		if (ret < 0)
1042 			return ret;
1043 	}
1044 
1045 	if (rtd->dai_link->ops && rtd->dai_link->ops->trigger) {
1046 		ret = rtd->dai_link->ops->trigger(substream, cmd);
1047 		if (ret < 0)
1048 			return ret;
1049 	}
1050 
1051 	return 0;
1052 }
1053 
1054 static int soc_pcm_bespoke_trigger(struct snd_pcm_substream *substream,
1055 				   int cmd)
1056 {
1057 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
1058 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
1059 	struct snd_soc_dai *codec_dai;
1060 	int i, ret;
1061 
1062 	for (i = 0; i < rtd->num_codecs; i++) {
1063 		codec_dai = rtd->codec_dais[i];
1064 		if (codec_dai->driver->ops &&
1065 		    codec_dai->driver->ops->bespoke_trigger) {
1066 			ret = codec_dai->driver->ops->bespoke_trigger(substream,
1067 								cmd, codec_dai);
1068 			if (ret < 0)
1069 				return ret;
1070 		}
1071 	}
1072 
1073 	if (cpu_dai->driver->ops && cpu_dai->driver->ops->bespoke_trigger) {
1074 		ret = cpu_dai->driver->ops->bespoke_trigger(substream, cmd, cpu_dai);
1075 		if (ret < 0)
1076 			return ret;
1077 	}
1078 	return 0;
1079 }
1080 /*
1081  * soc level wrapper for pointer callback
1082  * If cpu_dai, codec_dai, platform driver has the delay callback, than
1083  * the runtime->delay will be updated accordingly.
1084  */
1085 static snd_pcm_uframes_t soc_pcm_pointer(struct snd_pcm_substream *substream)
1086 {
1087 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
1088 	struct snd_soc_platform *platform = rtd->platform;
1089 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
1090 	struct snd_soc_dai *codec_dai;
1091 	struct snd_pcm_runtime *runtime = substream->runtime;
1092 	snd_pcm_uframes_t offset = 0;
1093 	snd_pcm_sframes_t delay = 0;
1094 	snd_pcm_sframes_t codec_delay = 0;
1095 	int i;
1096 
1097 	if (platform->driver->ops && platform->driver->ops->pointer)
1098 		offset = platform->driver->ops->pointer(substream);
1099 
1100 	if (cpu_dai->driver->ops && cpu_dai->driver->ops->delay)
1101 		delay += cpu_dai->driver->ops->delay(substream, cpu_dai);
1102 
1103 	for (i = 0; i < rtd->num_codecs; i++) {
1104 		codec_dai = rtd->codec_dais[i];
1105 		if (codec_dai->driver->ops && codec_dai->driver->ops->delay)
1106 			codec_delay = max(codec_delay,
1107 					codec_dai->driver->ops->delay(substream,
1108 								    codec_dai));
1109 	}
1110 	delay += codec_delay;
1111 
1112 	runtime->delay = delay;
1113 
1114 	return offset;
1115 }
1116 
1117 /* connect a FE and BE */
1118 static int dpcm_be_connect(struct snd_soc_pcm_runtime *fe,
1119 		struct snd_soc_pcm_runtime *be, int stream)
1120 {
1121 	struct snd_soc_dpcm *dpcm;
1122 
1123 	/* only add new dpcms */
1124 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
1125 		if (dpcm->be == be && dpcm->fe == fe)
1126 			return 0;
1127 	}
1128 
1129 	dpcm = kzalloc(sizeof(struct snd_soc_dpcm), GFP_KERNEL);
1130 	if (!dpcm)
1131 		return -ENOMEM;
1132 
1133 	dpcm->be = be;
1134 	dpcm->fe = fe;
1135 	be->dpcm[stream].runtime = fe->dpcm[stream].runtime;
1136 	dpcm->state = SND_SOC_DPCM_LINK_STATE_NEW;
1137 	list_add(&dpcm->list_be, &fe->dpcm[stream].be_clients);
1138 	list_add(&dpcm->list_fe, &be->dpcm[stream].fe_clients);
1139 
1140 	dev_dbg(fe->dev, "connected new DPCM %s path %s %s %s\n",
1141 			stream ? "capture" : "playback",  fe->dai_link->name,
1142 			stream ? "<-" : "->", be->dai_link->name);
1143 
1144 #ifdef CONFIG_DEBUG_FS
1145 	if (fe->debugfs_dpcm_root)
1146 		dpcm->debugfs_state = debugfs_create_u32(be->dai_link->name, 0644,
1147 				fe->debugfs_dpcm_root, &dpcm->state);
1148 #endif
1149 	return 1;
1150 }
1151 
1152 /* reparent a BE onto another FE */
1153 static void dpcm_be_reparent(struct snd_soc_pcm_runtime *fe,
1154 			struct snd_soc_pcm_runtime *be, int stream)
1155 {
1156 	struct snd_soc_dpcm *dpcm;
1157 	struct snd_pcm_substream *fe_substream, *be_substream;
1158 
1159 	/* reparent if BE is connected to other FEs */
1160 	if (!be->dpcm[stream].users)
1161 		return;
1162 
1163 	be_substream = snd_soc_dpcm_get_substream(be, stream);
1164 
1165 	list_for_each_entry(dpcm, &be->dpcm[stream].fe_clients, list_fe) {
1166 		if (dpcm->fe == fe)
1167 			continue;
1168 
1169 		dev_dbg(fe->dev, "reparent %s path %s %s %s\n",
1170 			stream ? "capture" : "playback",
1171 			dpcm->fe->dai_link->name,
1172 			stream ? "<-" : "->", dpcm->be->dai_link->name);
1173 
1174 		fe_substream = snd_soc_dpcm_get_substream(dpcm->fe, stream);
1175 		be_substream->runtime = fe_substream->runtime;
1176 		break;
1177 	}
1178 }
1179 
1180 /* disconnect a BE and FE */
1181 void dpcm_be_disconnect(struct snd_soc_pcm_runtime *fe, int stream)
1182 {
1183 	struct snd_soc_dpcm *dpcm, *d;
1184 
1185 	list_for_each_entry_safe(dpcm, d, &fe->dpcm[stream].be_clients, list_be) {
1186 		dev_dbg(fe->dev, "ASoC: BE %s disconnect check for %s\n",
1187 				stream ? "capture" : "playback",
1188 				dpcm->be->dai_link->name);
1189 
1190 		if (dpcm->state != SND_SOC_DPCM_LINK_STATE_FREE)
1191 			continue;
1192 
1193 		dev_dbg(fe->dev, "freed DSP %s path %s %s %s\n",
1194 			stream ? "capture" : "playback", fe->dai_link->name,
1195 			stream ? "<-" : "->", dpcm->be->dai_link->name);
1196 
1197 		/* BEs still alive need new FE */
1198 		dpcm_be_reparent(fe, dpcm->be, stream);
1199 
1200 #ifdef CONFIG_DEBUG_FS
1201 		debugfs_remove(dpcm->debugfs_state);
1202 #endif
1203 		list_del(&dpcm->list_be);
1204 		list_del(&dpcm->list_fe);
1205 		kfree(dpcm);
1206 	}
1207 }
1208 
1209 /* get BE for DAI widget and stream */
1210 static struct snd_soc_pcm_runtime *dpcm_get_be(struct snd_soc_card *card,
1211 		struct snd_soc_dapm_widget *widget, int stream)
1212 {
1213 	struct snd_soc_pcm_runtime *be;
1214 	int i;
1215 
1216 	if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
1217 		list_for_each_entry(be, &card->rtd_list, list) {
1218 
1219 			if (!be->dai_link->no_pcm)
1220 				continue;
1221 
1222 			if (be->cpu_dai->playback_widget == widget)
1223 				return be;
1224 
1225 			for (i = 0; i < be->num_codecs; i++) {
1226 				struct snd_soc_dai *dai = be->codec_dais[i];
1227 				if (dai->playback_widget == widget)
1228 					return be;
1229 			}
1230 		}
1231 	} else {
1232 
1233 		list_for_each_entry(be, &card->rtd_list, list) {
1234 
1235 			if (!be->dai_link->no_pcm)
1236 				continue;
1237 
1238 			if (be->cpu_dai->capture_widget == widget)
1239 				return be;
1240 
1241 			for (i = 0; i < be->num_codecs; i++) {
1242 				struct snd_soc_dai *dai = be->codec_dais[i];
1243 				if (dai->capture_widget == widget)
1244 					return be;
1245 			}
1246 		}
1247 	}
1248 
1249 	dev_err(card->dev, "ASoC: can't get %s BE for %s\n",
1250 		stream ? "capture" : "playback", widget->name);
1251 	return NULL;
1252 }
1253 
1254 static inline struct snd_soc_dapm_widget *
1255 	dai_get_widget(struct snd_soc_dai *dai, int stream)
1256 {
1257 	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
1258 		return dai->playback_widget;
1259 	else
1260 		return dai->capture_widget;
1261 }
1262 
1263 static int widget_in_list(struct snd_soc_dapm_widget_list *list,
1264 		struct snd_soc_dapm_widget *widget)
1265 {
1266 	int i;
1267 
1268 	for (i = 0; i < list->num_widgets; i++) {
1269 		if (widget == list->widgets[i])
1270 			return 1;
1271 	}
1272 
1273 	return 0;
1274 }
1275 
1276 static bool dpcm_end_walk_at_be(struct snd_soc_dapm_widget *widget,
1277 		enum snd_soc_dapm_direction dir)
1278 {
1279 	struct snd_soc_card *card = widget->dapm->card;
1280 	struct snd_soc_pcm_runtime *rtd;
1281 	int i;
1282 
1283 	if (dir == SND_SOC_DAPM_DIR_OUT) {
1284 		list_for_each_entry(rtd, &card->rtd_list, list) {
1285 			if (!rtd->dai_link->no_pcm)
1286 				continue;
1287 
1288 			if (rtd->cpu_dai->playback_widget == widget)
1289 				return true;
1290 
1291 			for (i = 0; i < rtd->num_codecs; ++i) {
1292 				struct snd_soc_dai *dai = rtd->codec_dais[i];
1293 				if (dai->playback_widget == widget)
1294 					return true;
1295 			}
1296 		}
1297 	} else { /* SND_SOC_DAPM_DIR_IN */
1298 		list_for_each_entry(rtd, &card->rtd_list, list) {
1299 			if (!rtd->dai_link->no_pcm)
1300 				continue;
1301 
1302 			if (rtd->cpu_dai->capture_widget == widget)
1303 				return true;
1304 
1305 			for (i = 0; i < rtd->num_codecs; ++i) {
1306 				struct snd_soc_dai *dai = rtd->codec_dais[i];
1307 				if (dai->capture_widget == widget)
1308 					return true;
1309 			}
1310 		}
1311 	}
1312 
1313 	return false;
1314 }
1315 
1316 int dpcm_path_get(struct snd_soc_pcm_runtime *fe,
1317 	int stream, struct snd_soc_dapm_widget_list **list)
1318 {
1319 	struct snd_soc_dai *cpu_dai = fe->cpu_dai;
1320 	int paths;
1321 
1322 	/* get number of valid DAI paths and their widgets */
1323 	paths = snd_soc_dapm_dai_get_connected_widgets(cpu_dai, stream, list,
1324 			dpcm_end_walk_at_be);
1325 
1326 	dev_dbg(fe->dev, "ASoC: found %d audio %s paths\n", paths,
1327 			stream ? "capture" : "playback");
1328 
1329 	return paths;
1330 }
1331 
1332 static int dpcm_prune_paths(struct snd_soc_pcm_runtime *fe, int stream,
1333 	struct snd_soc_dapm_widget_list **list_)
1334 {
1335 	struct snd_soc_dpcm *dpcm;
1336 	struct snd_soc_dapm_widget_list *list = *list_;
1337 	struct snd_soc_dapm_widget *widget;
1338 	int prune = 0;
1339 
1340 	/* Destroy any old FE <--> BE connections */
1341 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
1342 		unsigned int i;
1343 
1344 		/* is there a valid CPU DAI widget for this BE */
1345 		widget = dai_get_widget(dpcm->be->cpu_dai, stream);
1346 
1347 		/* prune the BE if it's no longer in our active list */
1348 		if (widget && widget_in_list(list, widget))
1349 			continue;
1350 
1351 		/* is there a valid CODEC DAI widget for this BE */
1352 		for (i = 0; i < dpcm->be->num_codecs; i++) {
1353 			struct snd_soc_dai *dai = dpcm->be->codec_dais[i];
1354 			widget = dai_get_widget(dai, stream);
1355 
1356 			/* prune the BE if it's no longer in our active list */
1357 			if (widget && widget_in_list(list, widget))
1358 				continue;
1359 		}
1360 
1361 		dev_dbg(fe->dev, "ASoC: pruning %s BE %s for %s\n",
1362 			stream ? "capture" : "playback",
1363 			dpcm->be->dai_link->name, fe->dai_link->name);
1364 		dpcm->state = SND_SOC_DPCM_LINK_STATE_FREE;
1365 		dpcm->be->dpcm[stream].runtime_update = SND_SOC_DPCM_UPDATE_BE;
1366 		prune++;
1367 	}
1368 
1369 	dev_dbg(fe->dev, "ASoC: found %d old BE paths for pruning\n", prune);
1370 	return prune;
1371 }
1372 
1373 static int dpcm_add_paths(struct snd_soc_pcm_runtime *fe, int stream,
1374 	struct snd_soc_dapm_widget_list **list_)
1375 {
1376 	struct snd_soc_card *card = fe->card;
1377 	struct snd_soc_dapm_widget_list *list = *list_;
1378 	struct snd_soc_pcm_runtime *be;
1379 	int i, new = 0, err;
1380 
1381 	/* Create any new FE <--> BE connections */
1382 	for (i = 0; i < list->num_widgets; i++) {
1383 
1384 		switch (list->widgets[i]->id) {
1385 		case snd_soc_dapm_dai_in:
1386 			if (stream != SNDRV_PCM_STREAM_PLAYBACK)
1387 				continue;
1388 			break;
1389 		case snd_soc_dapm_dai_out:
1390 			if (stream != SNDRV_PCM_STREAM_CAPTURE)
1391 				continue;
1392 			break;
1393 		default:
1394 			continue;
1395 		}
1396 
1397 		/* is there a valid BE rtd for this widget */
1398 		be = dpcm_get_be(card, list->widgets[i], stream);
1399 		if (!be) {
1400 			dev_err(fe->dev, "ASoC: no BE found for %s\n",
1401 					list->widgets[i]->name);
1402 			continue;
1403 		}
1404 
1405 		/* make sure BE is a real BE */
1406 		if (!be->dai_link->no_pcm)
1407 			continue;
1408 
1409 		/* don't connect if FE is not running */
1410 		if (!fe->dpcm[stream].runtime && !fe->fe_compr)
1411 			continue;
1412 
1413 		/* newly connected FE and BE */
1414 		err = dpcm_be_connect(fe, be, stream);
1415 		if (err < 0) {
1416 			dev_err(fe->dev, "ASoC: can't connect %s\n",
1417 				list->widgets[i]->name);
1418 			break;
1419 		} else if (err == 0) /* already connected */
1420 			continue;
1421 
1422 		/* new */
1423 		be->dpcm[stream].runtime_update = SND_SOC_DPCM_UPDATE_BE;
1424 		new++;
1425 	}
1426 
1427 	dev_dbg(fe->dev, "ASoC: found %d new BE paths\n", new);
1428 	return new;
1429 }
1430 
1431 /*
1432  * Find the corresponding BE DAIs that source or sink audio to this
1433  * FE substream.
1434  */
1435 int dpcm_process_paths(struct snd_soc_pcm_runtime *fe,
1436 	int stream, struct snd_soc_dapm_widget_list **list, int new)
1437 {
1438 	if (new)
1439 		return dpcm_add_paths(fe, stream, list);
1440 	else
1441 		return dpcm_prune_paths(fe, stream, list);
1442 }
1443 
1444 void dpcm_clear_pending_state(struct snd_soc_pcm_runtime *fe, int stream)
1445 {
1446 	struct snd_soc_dpcm *dpcm;
1447 
1448 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be)
1449 		dpcm->be->dpcm[stream].runtime_update =
1450 						SND_SOC_DPCM_UPDATE_NO;
1451 }
1452 
1453 static void dpcm_be_dai_startup_unwind(struct snd_soc_pcm_runtime *fe,
1454 	int stream)
1455 {
1456 	struct snd_soc_dpcm *dpcm;
1457 
1458 	/* disable any enabled and non active backends */
1459 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
1460 
1461 		struct snd_soc_pcm_runtime *be = dpcm->be;
1462 		struct snd_pcm_substream *be_substream =
1463 			snd_soc_dpcm_get_substream(be, stream);
1464 
1465 		if (be->dpcm[stream].users == 0)
1466 			dev_err(be->dev, "ASoC: no users %s at close - state %d\n",
1467 				stream ? "capture" : "playback",
1468 				be->dpcm[stream].state);
1469 
1470 		if (--be->dpcm[stream].users != 0)
1471 			continue;
1472 
1473 		if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_OPEN)
1474 			continue;
1475 
1476 		soc_pcm_close(be_substream);
1477 		be_substream->runtime = NULL;
1478 		be->dpcm[stream].state = SND_SOC_DPCM_STATE_CLOSE;
1479 	}
1480 }
1481 
1482 int dpcm_be_dai_startup(struct snd_soc_pcm_runtime *fe, int stream)
1483 {
1484 	struct snd_soc_dpcm *dpcm;
1485 	int err, count = 0;
1486 
1487 	/* only startup BE DAIs that are either sinks or sources to this FE DAI */
1488 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
1489 
1490 		struct snd_soc_pcm_runtime *be = dpcm->be;
1491 		struct snd_pcm_substream *be_substream =
1492 			snd_soc_dpcm_get_substream(be, stream);
1493 
1494 		if (!be_substream) {
1495 			dev_err(be->dev, "ASoC: no backend %s stream\n",
1496 				stream ? "capture" : "playback");
1497 			continue;
1498 		}
1499 
1500 		/* is this op for this BE ? */
1501 		if (!snd_soc_dpcm_be_can_update(fe, be, stream))
1502 			continue;
1503 
1504 		/* first time the dpcm is open ? */
1505 		if (be->dpcm[stream].users == DPCM_MAX_BE_USERS)
1506 			dev_err(be->dev, "ASoC: too many users %s at open %d\n",
1507 				stream ? "capture" : "playback",
1508 				be->dpcm[stream].state);
1509 
1510 		if (be->dpcm[stream].users++ != 0)
1511 			continue;
1512 
1513 		if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_NEW) &&
1514 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_CLOSE))
1515 			continue;
1516 
1517 		dev_dbg(be->dev, "ASoC: open %s BE %s\n",
1518 			stream ? "capture" : "playback", be->dai_link->name);
1519 
1520 		be_substream->runtime = be->dpcm[stream].runtime;
1521 		err = soc_pcm_open(be_substream);
1522 		if (err < 0) {
1523 			dev_err(be->dev, "ASoC: BE open failed %d\n", err);
1524 			be->dpcm[stream].users--;
1525 			if (be->dpcm[stream].users < 0)
1526 				dev_err(be->dev, "ASoC: no users %s at unwind %d\n",
1527 					stream ? "capture" : "playback",
1528 					be->dpcm[stream].state);
1529 
1530 			be->dpcm[stream].state = SND_SOC_DPCM_STATE_CLOSE;
1531 			goto unwind;
1532 		}
1533 
1534 		be->dpcm[stream].state = SND_SOC_DPCM_STATE_OPEN;
1535 		count++;
1536 	}
1537 
1538 	return count;
1539 
1540 unwind:
1541 	/* disable any enabled and non active backends */
1542 	list_for_each_entry_continue_reverse(dpcm, &fe->dpcm[stream].be_clients, list_be) {
1543 		struct snd_soc_pcm_runtime *be = dpcm->be;
1544 		struct snd_pcm_substream *be_substream =
1545 			snd_soc_dpcm_get_substream(be, stream);
1546 
1547 		if (!snd_soc_dpcm_be_can_update(fe, be, stream))
1548 			continue;
1549 
1550 		if (be->dpcm[stream].users == 0)
1551 			dev_err(be->dev, "ASoC: no users %s at close %d\n",
1552 				stream ? "capture" : "playback",
1553 				be->dpcm[stream].state);
1554 
1555 		if (--be->dpcm[stream].users != 0)
1556 			continue;
1557 
1558 		if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_OPEN)
1559 			continue;
1560 
1561 		soc_pcm_close(be_substream);
1562 		be_substream->runtime = NULL;
1563 		be->dpcm[stream].state = SND_SOC_DPCM_STATE_CLOSE;
1564 	}
1565 
1566 	return err;
1567 }
1568 
1569 static void dpcm_init_runtime_hw(struct snd_pcm_runtime *runtime,
1570 				 struct snd_soc_pcm_stream *stream,
1571 				 u64 formats)
1572 {
1573 	runtime->hw.rate_min = stream->rate_min;
1574 	runtime->hw.rate_max = stream->rate_max;
1575 	runtime->hw.channels_min = stream->channels_min;
1576 	runtime->hw.channels_max = stream->channels_max;
1577 	if (runtime->hw.formats)
1578 		runtime->hw.formats &= formats & stream->formats;
1579 	else
1580 		runtime->hw.formats = formats & stream->formats;
1581 	runtime->hw.rates = stream->rates;
1582 }
1583 
1584 static u64 dpcm_runtime_base_format(struct snd_pcm_substream *substream)
1585 {
1586 	struct snd_soc_pcm_runtime *fe = substream->private_data;
1587 	struct snd_soc_dpcm *dpcm;
1588 	u64 formats = ULLONG_MAX;
1589 	int stream = substream->stream;
1590 
1591 	if (!fe->dai_link->dpcm_merged_format)
1592 		return formats;
1593 
1594 	/*
1595 	 * It returns merged BE codec format
1596 	 * if FE want to use it (= dpcm_merged_format)
1597 	 */
1598 
1599 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
1600 		struct snd_soc_pcm_runtime *be = dpcm->be;
1601 		struct snd_soc_dai_driver *codec_dai_drv;
1602 		struct snd_soc_pcm_stream *codec_stream;
1603 		int i;
1604 
1605 		for (i = 0; i < be->num_codecs; i++) {
1606 			codec_dai_drv = be->codec_dais[i]->driver;
1607 			if (stream == SNDRV_PCM_STREAM_PLAYBACK)
1608 				codec_stream = &codec_dai_drv->playback;
1609 			else
1610 				codec_stream = &codec_dai_drv->capture;
1611 
1612 			formats &= codec_stream->formats;
1613 		}
1614 	}
1615 
1616 	return formats;
1617 }
1618 
1619 static void dpcm_set_fe_runtime(struct snd_pcm_substream *substream)
1620 {
1621 	struct snd_pcm_runtime *runtime = substream->runtime;
1622 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
1623 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
1624 	struct snd_soc_dai_driver *cpu_dai_drv = cpu_dai->driver;
1625 	u64 format = dpcm_runtime_base_format(substream);
1626 
1627 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
1628 		dpcm_init_runtime_hw(runtime, &cpu_dai_drv->playback, format);
1629 	else
1630 		dpcm_init_runtime_hw(runtime, &cpu_dai_drv->capture, format);
1631 }
1632 
1633 static int dpcm_fe_dai_do_trigger(struct snd_pcm_substream *substream, int cmd);
1634 
1635 /* Set FE's runtime_update state; the state is protected via PCM stream lock
1636  * for avoiding the race with trigger callback.
1637  * If the state is unset and a trigger is pending while the previous operation,
1638  * process the pending trigger action here.
1639  */
1640 static void dpcm_set_fe_update_state(struct snd_soc_pcm_runtime *fe,
1641 				     int stream, enum snd_soc_dpcm_update state)
1642 {
1643 	struct snd_pcm_substream *substream =
1644 		snd_soc_dpcm_get_substream(fe, stream);
1645 
1646 	snd_pcm_stream_lock_irq(substream);
1647 	if (state == SND_SOC_DPCM_UPDATE_NO && fe->dpcm[stream].trigger_pending) {
1648 		dpcm_fe_dai_do_trigger(substream,
1649 				       fe->dpcm[stream].trigger_pending - 1);
1650 		fe->dpcm[stream].trigger_pending = 0;
1651 	}
1652 	fe->dpcm[stream].runtime_update = state;
1653 	snd_pcm_stream_unlock_irq(substream);
1654 }
1655 
1656 static int dpcm_apply_symmetry(struct snd_pcm_substream *fe_substream,
1657 			       int stream)
1658 {
1659 	struct snd_soc_dpcm *dpcm;
1660 	struct snd_soc_pcm_runtime *fe = fe_substream->private_data;
1661 	struct snd_soc_dai *fe_cpu_dai = fe->cpu_dai;
1662 	int err;
1663 
1664 	/* apply symmetry for FE */
1665 	if (soc_pcm_has_symmetry(fe_substream))
1666 		fe_substream->runtime->hw.info |= SNDRV_PCM_INFO_JOINT_DUPLEX;
1667 
1668 	/* Symmetry only applies if we've got an active stream. */
1669 	if (fe_cpu_dai->active) {
1670 		err = soc_pcm_apply_symmetry(fe_substream, fe_cpu_dai);
1671 		if (err < 0)
1672 			return err;
1673 	}
1674 
1675 	/* apply symmetry for BE */
1676 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
1677 		struct snd_soc_pcm_runtime *be = dpcm->be;
1678 		struct snd_pcm_substream *be_substream =
1679 			snd_soc_dpcm_get_substream(be, stream);
1680 		struct snd_soc_pcm_runtime *rtd = be_substream->private_data;
1681 		int i;
1682 
1683 		if (rtd->dai_link->be_hw_params_fixup)
1684 			continue;
1685 
1686 		if (soc_pcm_has_symmetry(be_substream))
1687 			be_substream->runtime->hw.info |= SNDRV_PCM_INFO_JOINT_DUPLEX;
1688 
1689 		/* Symmetry only applies if we've got an active stream. */
1690 		if (rtd->cpu_dai->active) {
1691 			err = soc_pcm_apply_symmetry(be_substream, rtd->cpu_dai);
1692 			if (err < 0)
1693 				return err;
1694 		}
1695 
1696 		for (i = 0; i < rtd->num_codecs; i++) {
1697 			if (rtd->codec_dais[i]->active) {
1698 				err = soc_pcm_apply_symmetry(be_substream,
1699 							     rtd->codec_dais[i]);
1700 				if (err < 0)
1701 					return err;
1702 			}
1703 		}
1704 	}
1705 
1706 	return 0;
1707 }
1708 
1709 static int dpcm_fe_dai_startup(struct snd_pcm_substream *fe_substream)
1710 {
1711 	struct snd_soc_pcm_runtime *fe = fe_substream->private_data;
1712 	struct snd_pcm_runtime *runtime = fe_substream->runtime;
1713 	int stream = fe_substream->stream, ret = 0;
1714 
1715 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_FE);
1716 
1717 	ret = dpcm_be_dai_startup(fe, fe_substream->stream);
1718 	if (ret < 0) {
1719 		dev_err(fe->dev,"ASoC: failed to start some BEs %d\n", ret);
1720 		goto be_err;
1721 	}
1722 
1723 	dev_dbg(fe->dev, "ASoC: open FE %s\n", fe->dai_link->name);
1724 
1725 	/* start the DAI frontend */
1726 	ret = soc_pcm_open(fe_substream);
1727 	if (ret < 0) {
1728 		dev_err(fe->dev,"ASoC: failed to start FE %d\n", ret);
1729 		goto unwind;
1730 	}
1731 
1732 	fe->dpcm[stream].state = SND_SOC_DPCM_STATE_OPEN;
1733 
1734 	dpcm_set_fe_runtime(fe_substream);
1735 	snd_pcm_limit_hw_rates(runtime);
1736 
1737 	ret = dpcm_apply_symmetry(fe_substream, stream);
1738 	if (ret < 0) {
1739 		dev_err(fe->dev, "ASoC: failed to apply dpcm symmetry %d\n",
1740 			ret);
1741 		goto unwind;
1742 	}
1743 
1744 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_NO);
1745 	return 0;
1746 
1747 unwind:
1748 	dpcm_be_dai_startup_unwind(fe, fe_substream->stream);
1749 be_err:
1750 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_NO);
1751 	return ret;
1752 }
1753 
1754 int dpcm_be_dai_shutdown(struct snd_soc_pcm_runtime *fe, int stream)
1755 {
1756 	struct snd_soc_dpcm *dpcm;
1757 
1758 	/* only shutdown BEs that are either sinks or sources to this FE DAI */
1759 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
1760 
1761 		struct snd_soc_pcm_runtime *be = dpcm->be;
1762 		struct snd_pcm_substream *be_substream =
1763 			snd_soc_dpcm_get_substream(be, stream);
1764 
1765 		/* is this op for this BE ? */
1766 		if (!snd_soc_dpcm_be_can_update(fe, be, stream))
1767 			continue;
1768 
1769 		if (be->dpcm[stream].users == 0)
1770 			dev_err(be->dev, "ASoC: no users %s at close - state %d\n",
1771 				stream ? "capture" : "playback",
1772 				be->dpcm[stream].state);
1773 
1774 		if (--be->dpcm[stream].users != 0)
1775 			continue;
1776 
1777 		if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_FREE) &&
1778 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_OPEN))
1779 			continue;
1780 
1781 		dev_dbg(be->dev, "ASoC: close BE %s\n",
1782 			be->dai_link->name);
1783 
1784 		soc_pcm_close(be_substream);
1785 		be_substream->runtime = NULL;
1786 
1787 		be->dpcm[stream].state = SND_SOC_DPCM_STATE_CLOSE;
1788 	}
1789 	return 0;
1790 }
1791 
1792 static int dpcm_fe_dai_shutdown(struct snd_pcm_substream *substream)
1793 {
1794 	struct snd_soc_pcm_runtime *fe = substream->private_data;
1795 	int stream = substream->stream;
1796 
1797 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_FE);
1798 
1799 	/* shutdown the BEs */
1800 	dpcm_be_dai_shutdown(fe, substream->stream);
1801 
1802 	dev_dbg(fe->dev, "ASoC: close FE %s\n", fe->dai_link->name);
1803 
1804 	/* now shutdown the frontend */
1805 	soc_pcm_close(substream);
1806 
1807 	/* run the stream event for each BE */
1808 	dpcm_dapm_stream_event(fe, stream, SND_SOC_DAPM_STREAM_STOP);
1809 
1810 	fe->dpcm[stream].state = SND_SOC_DPCM_STATE_CLOSE;
1811 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_NO);
1812 	return 0;
1813 }
1814 
1815 int dpcm_be_dai_hw_free(struct snd_soc_pcm_runtime *fe, int stream)
1816 {
1817 	struct snd_soc_dpcm *dpcm;
1818 
1819 	/* only hw_params backends that are either sinks or sources
1820 	 * to this frontend DAI */
1821 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
1822 
1823 		struct snd_soc_pcm_runtime *be = dpcm->be;
1824 		struct snd_pcm_substream *be_substream =
1825 			snd_soc_dpcm_get_substream(be, stream);
1826 
1827 		/* is this op for this BE ? */
1828 		if (!snd_soc_dpcm_be_can_update(fe, be, stream))
1829 			continue;
1830 
1831 		/* only free hw when no longer used - check all FEs */
1832 		if (!snd_soc_dpcm_can_be_free_stop(fe, be, stream))
1833 				continue;
1834 
1835 		/* do not free hw if this BE is used by other FE */
1836 		if (be->dpcm[stream].users > 1)
1837 			continue;
1838 
1839 		if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_PARAMS) &&
1840 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PREPARE) &&
1841 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_FREE) &&
1842 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED) &&
1843 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP) &&
1844 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_SUSPEND))
1845 			continue;
1846 
1847 		dev_dbg(be->dev, "ASoC: hw_free BE %s\n",
1848 			be->dai_link->name);
1849 
1850 		soc_pcm_hw_free(be_substream);
1851 
1852 		be->dpcm[stream].state = SND_SOC_DPCM_STATE_HW_FREE;
1853 	}
1854 
1855 	return 0;
1856 }
1857 
1858 static int dpcm_fe_dai_hw_free(struct snd_pcm_substream *substream)
1859 {
1860 	struct snd_soc_pcm_runtime *fe = substream->private_data;
1861 	int err, stream = substream->stream;
1862 
1863 	mutex_lock_nested(&fe->card->mutex, SND_SOC_CARD_CLASS_RUNTIME);
1864 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_FE);
1865 
1866 	dev_dbg(fe->dev, "ASoC: hw_free FE %s\n", fe->dai_link->name);
1867 
1868 	/* call hw_free on the frontend */
1869 	err = soc_pcm_hw_free(substream);
1870 	if (err < 0)
1871 		dev_err(fe->dev,"ASoC: hw_free FE %s failed\n",
1872 			fe->dai_link->name);
1873 
1874 	/* only hw_params backends that are either sinks or sources
1875 	 * to this frontend DAI */
1876 	err = dpcm_be_dai_hw_free(fe, stream);
1877 
1878 	fe->dpcm[stream].state = SND_SOC_DPCM_STATE_HW_FREE;
1879 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_NO);
1880 
1881 	mutex_unlock(&fe->card->mutex);
1882 	return 0;
1883 }
1884 
1885 int dpcm_be_dai_hw_params(struct snd_soc_pcm_runtime *fe, int stream)
1886 {
1887 	struct snd_soc_dpcm *dpcm;
1888 	int ret;
1889 
1890 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
1891 
1892 		struct snd_soc_pcm_runtime *be = dpcm->be;
1893 		struct snd_pcm_substream *be_substream =
1894 			snd_soc_dpcm_get_substream(be, stream);
1895 
1896 		/* is this op for this BE ? */
1897 		if (!snd_soc_dpcm_be_can_update(fe, be, stream))
1898 			continue;
1899 
1900 		/* copy params for each dpcm */
1901 		memcpy(&dpcm->hw_params, &fe->dpcm[stream].hw_params,
1902 				sizeof(struct snd_pcm_hw_params));
1903 
1904 		/* perform any hw_params fixups */
1905 		if (be->dai_link->be_hw_params_fixup) {
1906 			ret = be->dai_link->be_hw_params_fixup(be,
1907 					&dpcm->hw_params);
1908 			if (ret < 0) {
1909 				dev_err(be->dev,
1910 					"ASoC: hw_params BE fixup failed %d\n",
1911 					ret);
1912 				goto unwind;
1913 			}
1914 		}
1915 
1916 		/* only allow hw_params() if no connected FEs are running */
1917 		if (!snd_soc_dpcm_can_be_params(fe, be, stream))
1918 			continue;
1919 
1920 		if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_OPEN) &&
1921 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_PARAMS) &&
1922 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_FREE))
1923 			continue;
1924 
1925 		dev_dbg(be->dev, "ASoC: hw_params BE %s\n",
1926 			be->dai_link->name);
1927 
1928 		ret = soc_pcm_hw_params(be_substream, &dpcm->hw_params);
1929 		if (ret < 0) {
1930 			dev_err(dpcm->be->dev,
1931 				"ASoC: hw_params BE failed %d\n", ret);
1932 			goto unwind;
1933 		}
1934 
1935 		be->dpcm[stream].state = SND_SOC_DPCM_STATE_HW_PARAMS;
1936 	}
1937 	return 0;
1938 
1939 unwind:
1940 	/* disable any enabled and non active backends */
1941 	list_for_each_entry_continue_reverse(dpcm, &fe->dpcm[stream].be_clients, list_be) {
1942 		struct snd_soc_pcm_runtime *be = dpcm->be;
1943 		struct snd_pcm_substream *be_substream =
1944 			snd_soc_dpcm_get_substream(be, stream);
1945 
1946 		if (!snd_soc_dpcm_be_can_update(fe, be, stream))
1947 			continue;
1948 
1949 		/* only allow hw_free() if no connected FEs are running */
1950 		if (!snd_soc_dpcm_can_be_free_stop(fe, be, stream))
1951 			continue;
1952 
1953 		if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_OPEN) &&
1954 		   (be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_PARAMS) &&
1955 		   (be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_FREE) &&
1956 		   (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP))
1957 			continue;
1958 
1959 		soc_pcm_hw_free(be_substream);
1960 	}
1961 
1962 	return ret;
1963 }
1964 
1965 static int dpcm_fe_dai_hw_params(struct snd_pcm_substream *substream,
1966 				 struct snd_pcm_hw_params *params)
1967 {
1968 	struct snd_soc_pcm_runtime *fe = substream->private_data;
1969 	int ret, stream = substream->stream;
1970 
1971 	mutex_lock_nested(&fe->card->mutex, SND_SOC_CARD_CLASS_RUNTIME);
1972 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_FE);
1973 
1974 	memcpy(&fe->dpcm[substream->stream].hw_params, params,
1975 			sizeof(struct snd_pcm_hw_params));
1976 	ret = dpcm_be_dai_hw_params(fe, substream->stream);
1977 	if (ret < 0) {
1978 		dev_err(fe->dev,"ASoC: hw_params BE failed %d\n", ret);
1979 		goto out;
1980 	}
1981 
1982 	dev_dbg(fe->dev, "ASoC: hw_params FE %s rate %d chan %x fmt %d\n",
1983 			fe->dai_link->name, params_rate(params),
1984 			params_channels(params), params_format(params));
1985 
1986 	/* call hw_params on the frontend */
1987 	ret = soc_pcm_hw_params(substream, params);
1988 	if (ret < 0) {
1989 		dev_err(fe->dev,"ASoC: hw_params FE failed %d\n", ret);
1990 		dpcm_be_dai_hw_free(fe, stream);
1991 	 } else
1992 		fe->dpcm[stream].state = SND_SOC_DPCM_STATE_HW_PARAMS;
1993 
1994 out:
1995 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_NO);
1996 	mutex_unlock(&fe->card->mutex);
1997 	return ret;
1998 }
1999 
2000 static int dpcm_do_trigger(struct snd_soc_dpcm *dpcm,
2001 		struct snd_pcm_substream *substream, int cmd)
2002 {
2003 	int ret;
2004 
2005 	dev_dbg(dpcm->be->dev, "ASoC: trigger BE %s cmd %d\n",
2006 			dpcm->be->dai_link->name, cmd);
2007 
2008 	ret = soc_pcm_trigger(substream, cmd);
2009 	if (ret < 0)
2010 		dev_err(dpcm->be->dev,"ASoC: trigger BE failed %d\n", ret);
2011 
2012 	return ret;
2013 }
2014 
2015 int dpcm_be_dai_trigger(struct snd_soc_pcm_runtime *fe, int stream,
2016 			       int cmd)
2017 {
2018 	struct snd_soc_dpcm *dpcm;
2019 	int ret = 0;
2020 
2021 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
2022 
2023 		struct snd_soc_pcm_runtime *be = dpcm->be;
2024 		struct snd_pcm_substream *be_substream =
2025 			snd_soc_dpcm_get_substream(be, stream);
2026 
2027 		/* is this op for this BE ? */
2028 		if (!snd_soc_dpcm_be_can_update(fe, be, stream))
2029 			continue;
2030 
2031 		switch (cmd) {
2032 		case SNDRV_PCM_TRIGGER_START:
2033 			if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_PREPARE) &&
2034 			    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP))
2035 				continue;
2036 
2037 			ret = dpcm_do_trigger(dpcm, be_substream, cmd);
2038 			if (ret)
2039 				return ret;
2040 
2041 			be->dpcm[stream].state = SND_SOC_DPCM_STATE_START;
2042 			break;
2043 		case SNDRV_PCM_TRIGGER_RESUME:
2044 			if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_SUSPEND))
2045 				continue;
2046 
2047 			ret = dpcm_do_trigger(dpcm, be_substream, cmd);
2048 			if (ret)
2049 				return ret;
2050 
2051 			be->dpcm[stream].state = SND_SOC_DPCM_STATE_START;
2052 			break;
2053 		case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
2054 			if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_PAUSED))
2055 				continue;
2056 
2057 			ret = dpcm_do_trigger(dpcm, be_substream, cmd);
2058 			if (ret)
2059 				return ret;
2060 
2061 			be->dpcm[stream].state = SND_SOC_DPCM_STATE_START;
2062 			break;
2063 		case SNDRV_PCM_TRIGGER_STOP:
2064 			if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_START)
2065 				continue;
2066 
2067 			if (!snd_soc_dpcm_can_be_free_stop(fe, be, stream))
2068 				continue;
2069 
2070 			ret = dpcm_do_trigger(dpcm, be_substream, cmd);
2071 			if (ret)
2072 				return ret;
2073 
2074 			be->dpcm[stream].state = SND_SOC_DPCM_STATE_STOP;
2075 			break;
2076 		case SNDRV_PCM_TRIGGER_SUSPEND:
2077 			if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_START)
2078 				continue;
2079 
2080 			if (!snd_soc_dpcm_can_be_free_stop(fe, be, stream))
2081 				continue;
2082 
2083 			ret = dpcm_do_trigger(dpcm, be_substream, cmd);
2084 			if (ret)
2085 				return ret;
2086 
2087 			be->dpcm[stream].state = SND_SOC_DPCM_STATE_SUSPEND;
2088 			break;
2089 		case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
2090 			if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_START)
2091 				continue;
2092 
2093 			if (!snd_soc_dpcm_can_be_free_stop(fe, be, stream))
2094 				continue;
2095 
2096 			ret = dpcm_do_trigger(dpcm, be_substream, cmd);
2097 			if (ret)
2098 				return ret;
2099 
2100 			be->dpcm[stream].state = SND_SOC_DPCM_STATE_PAUSED;
2101 			break;
2102 		}
2103 	}
2104 
2105 	return ret;
2106 }
2107 EXPORT_SYMBOL_GPL(dpcm_be_dai_trigger);
2108 
2109 static int dpcm_fe_dai_do_trigger(struct snd_pcm_substream *substream, int cmd)
2110 {
2111 	struct snd_soc_pcm_runtime *fe = substream->private_data;
2112 	int stream = substream->stream, ret;
2113 	enum snd_soc_dpcm_trigger trigger = fe->dai_link->trigger[stream];
2114 
2115 	fe->dpcm[stream].runtime_update = SND_SOC_DPCM_UPDATE_FE;
2116 
2117 	switch (trigger) {
2118 	case SND_SOC_DPCM_TRIGGER_PRE:
2119 		/* call trigger on the frontend before the backend. */
2120 
2121 		dev_dbg(fe->dev, "ASoC: pre trigger FE %s cmd %d\n",
2122 				fe->dai_link->name, cmd);
2123 
2124 		ret = soc_pcm_trigger(substream, cmd);
2125 		if (ret < 0) {
2126 			dev_err(fe->dev,"ASoC: trigger FE failed %d\n", ret);
2127 			goto out;
2128 		}
2129 
2130 		ret = dpcm_be_dai_trigger(fe, substream->stream, cmd);
2131 		break;
2132 	case SND_SOC_DPCM_TRIGGER_POST:
2133 		/* call trigger on the frontend after the backend. */
2134 
2135 		ret = dpcm_be_dai_trigger(fe, substream->stream, cmd);
2136 		if (ret < 0) {
2137 			dev_err(fe->dev,"ASoC: trigger FE failed %d\n", ret);
2138 			goto out;
2139 		}
2140 
2141 		dev_dbg(fe->dev, "ASoC: post trigger FE %s cmd %d\n",
2142 				fe->dai_link->name, cmd);
2143 
2144 		ret = soc_pcm_trigger(substream, cmd);
2145 		break;
2146 	case SND_SOC_DPCM_TRIGGER_BESPOKE:
2147 		/* bespoke trigger() - handles both FE and BEs */
2148 
2149 		dev_dbg(fe->dev, "ASoC: bespoke trigger FE %s cmd %d\n",
2150 				fe->dai_link->name, cmd);
2151 
2152 		ret = soc_pcm_bespoke_trigger(substream, cmd);
2153 		if (ret < 0) {
2154 			dev_err(fe->dev,"ASoC: trigger FE failed %d\n", ret);
2155 			goto out;
2156 		}
2157 		break;
2158 	default:
2159 		dev_err(fe->dev, "ASoC: invalid trigger cmd %d for %s\n", cmd,
2160 				fe->dai_link->name);
2161 		ret = -EINVAL;
2162 		goto out;
2163 	}
2164 
2165 	switch (cmd) {
2166 	case SNDRV_PCM_TRIGGER_START:
2167 	case SNDRV_PCM_TRIGGER_RESUME:
2168 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
2169 		fe->dpcm[stream].state = SND_SOC_DPCM_STATE_START;
2170 		break;
2171 	case SNDRV_PCM_TRIGGER_STOP:
2172 	case SNDRV_PCM_TRIGGER_SUSPEND:
2173 		fe->dpcm[stream].state = SND_SOC_DPCM_STATE_STOP;
2174 		break;
2175 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
2176 		fe->dpcm[stream].state = SND_SOC_DPCM_STATE_PAUSED;
2177 		break;
2178 	}
2179 
2180 out:
2181 	fe->dpcm[stream].runtime_update = SND_SOC_DPCM_UPDATE_NO;
2182 	return ret;
2183 }
2184 
2185 static int dpcm_fe_dai_trigger(struct snd_pcm_substream *substream, int cmd)
2186 {
2187 	struct snd_soc_pcm_runtime *fe = substream->private_data;
2188 	int stream = substream->stream;
2189 
2190 	/* if FE's runtime_update is already set, we're in race;
2191 	 * process this trigger later at exit
2192 	 */
2193 	if (fe->dpcm[stream].runtime_update != SND_SOC_DPCM_UPDATE_NO) {
2194 		fe->dpcm[stream].trigger_pending = cmd + 1;
2195 		return 0; /* delayed, assuming it's successful */
2196 	}
2197 
2198 	/* we're alone, let's trigger */
2199 	return dpcm_fe_dai_do_trigger(substream, cmd);
2200 }
2201 
2202 int dpcm_be_dai_prepare(struct snd_soc_pcm_runtime *fe, int stream)
2203 {
2204 	struct snd_soc_dpcm *dpcm;
2205 	int ret = 0;
2206 
2207 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
2208 
2209 		struct snd_soc_pcm_runtime *be = dpcm->be;
2210 		struct snd_pcm_substream *be_substream =
2211 			snd_soc_dpcm_get_substream(be, stream);
2212 
2213 		/* is this op for this BE ? */
2214 		if (!snd_soc_dpcm_be_can_update(fe, be, stream))
2215 			continue;
2216 
2217 		if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_PARAMS) &&
2218 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP) &&
2219 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_SUSPEND))
2220 			continue;
2221 
2222 		dev_dbg(be->dev, "ASoC: prepare BE %s\n",
2223 			be->dai_link->name);
2224 
2225 		ret = soc_pcm_prepare(be_substream);
2226 		if (ret < 0) {
2227 			dev_err(be->dev, "ASoC: backend prepare failed %d\n",
2228 				ret);
2229 			break;
2230 		}
2231 
2232 		be->dpcm[stream].state = SND_SOC_DPCM_STATE_PREPARE;
2233 	}
2234 	return ret;
2235 }
2236 
2237 static int dpcm_fe_dai_prepare(struct snd_pcm_substream *substream)
2238 {
2239 	struct snd_soc_pcm_runtime *fe = substream->private_data;
2240 	int stream = substream->stream, ret = 0;
2241 
2242 	mutex_lock_nested(&fe->card->mutex, SND_SOC_CARD_CLASS_RUNTIME);
2243 
2244 	dev_dbg(fe->dev, "ASoC: prepare FE %s\n", fe->dai_link->name);
2245 
2246 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_FE);
2247 
2248 	/* there is no point preparing this FE if there are no BEs */
2249 	if (list_empty(&fe->dpcm[stream].be_clients)) {
2250 		dev_err(fe->dev, "ASoC: no backend DAIs enabled for %s\n",
2251 				fe->dai_link->name);
2252 		ret = -EINVAL;
2253 		goto out;
2254 	}
2255 
2256 	ret = dpcm_be_dai_prepare(fe, substream->stream);
2257 	if (ret < 0)
2258 		goto out;
2259 
2260 	/* call prepare on the frontend */
2261 	ret = soc_pcm_prepare(substream);
2262 	if (ret < 0) {
2263 		dev_err(fe->dev,"ASoC: prepare FE %s failed\n",
2264 			fe->dai_link->name);
2265 		goto out;
2266 	}
2267 
2268 	/* run the stream event for each BE */
2269 	dpcm_dapm_stream_event(fe, stream, SND_SOC_DAPM_STREAM_START);
2270 	fe->dpcm[stream].state = SND_SOC_DPCM_STATE_PREPARE;
2271 
2272 out:
2273 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_NO);
2274 	mutex_unlock(&fe->card->mutex);
2275 
2276 	return ret;
2277 }
2278 
2279 static int soc_pcm_ioctl(struct snd_pcm_substream *substream,
2280 		     unsigned int cmd, void *arg)
2281 {
2282 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
2283 	struct snd_soc_platform *platform = rtd->platform;
2284 
2285 	if (platform->driver->ops && platform->driver->ops->ioctl)
2286 		return platform->driver->ops->ioctl(substream, cmd, arg);
2287 	return snd_pcm_lib_ioctl(substream, cmd, arg);
2288 }
2289 
2290 static int dpcm_run_update_shutdown(struct snd_soc_pcm_runtime *fe, int stream)
2291 {
2292 	struct snd_pcm_substream *substream =
2293 		snd_soc_dpcm_get_substream(fe, stream);
2294 	enum snd_soc_dpcm_trigger trigger = fe->dai_link->trigger[stream];
2295 	int err;
2296 
2297 	dev_dbg(fe->dev, "ASoC: runtime %s close on FE %s\n",
2298 			stream ? "capture" : "playback", fe->dai_link->name);
2299 
2300 	if (trigger == SND_SOC_DPCM_TRIGGER_BESPOKE) {
2301 		/* call bespoke trigger - FE takes care of all BE triggers */
2302 		dev_dbg(fe->dev, "ASoC: bespoke trigger FE %s cmd stop\n",
2303 				fe->dai_link->name);
2304 
2305 		err = soc_pcm_bespoke_trigger(substream, SNDRV_PCM_TRIGGER_STOP);
2306 		if (err < 0)
2307 			dev_err(fe->dev,"ASoC: trigger FE failed %d\n", err);
2308 	} else {
2309 		dev_dbg(fe->dev, "ASoC: trigger FE %s cmd stop\n",
2310 			fe->dai_link->name);
2311 
2312 		err = dpcm_be_dai_trigger(fe, stream, SNDRV_PCM_TRIGGER_STOP);
2313 		if (err < 0)
2314 			dev_err(fe->dev,"ASoC: trigger FE failed %d\n", err);
2315 	}
2316 
2317 	err = dpcm_be_dai_hw_free(fe, stream);
2318 	if (err < 0)
2319 		dev_err(fe->dev,"ASoC: hw_free FE failed %d\n", err);
2320 
2321 	err = dpcm_be_dai_shutdown(fe, stream);
2322 	if (err < 0)
2323 		dev_err(fe->dev,"ASoC: shutdown FE failed %d\n", err);
2324 
2325 	/* run the stream event for each BE */
2326 	dpcm_dapm_stream_event(fe, stream, SND_SOC_DAPM_STREAM_NOP);
2327 
2328 	return 0;
2329 }
2330 
2331 static int dpcm_run_update_startup(struct snd_soc_pcm_runtime *fe, int stream)
2332 {
2333 	struct snd_pcm_substream *substream =
2334 		snd_soc_dpcm_get_substream(fe, stream);
2335 	struct snd_soc_dpcm *dpcm;
2336 	enum snd_soc_dpcm_trigger trigger = fe->dai_link->trigger[stream];
2337 	int ret;
2338 
2339 	dev_dbg(fe->dev, "ASoC: runtime %s open on FE %s\n",
2340 			stream ? "capture" : "playback", fe->dai_link->name);
2341 
2342 	/* Only start the BE if the FE is ready */
2343 	if (fe->dpcm[stream].state == SND_SOC_DPCM_STATE_HW_FREE ||
2344 		fe->dpcm[stream].state == SND_SOC_DPCM_STATE_CLOSE)
2345 		return -EINVAL;
2346 
2347 	/* startup must always be called for new BEs */
2348 	ret = dpcm_be_dai_startup(fe, stream);
2349 	if (ret < 0)
2350 		goto disconnect;
2351 
2352 	/* keep going if FE state is > open */
2353 	if (fe->dpcm[stream].state == SND_SOC_DPCM_STATE_OPEN)
2354 		return 0;
2355 
2356 	ret = dpcm_be_dai_hw_params(fe, stream);
2357 	if (ret < 0)
2358 		goto close;
2359 
2360 	/* keep going if FE state is > hw_params */
2361 	if (fe->dpcm[stream].state == SND_SOC_DPCM_STATE_HW_PARAMS)
2362 		return 0;
2363 
2364 
2365 	ret = dpcm_be_dai_prepare(fe, stream);
2366 	if (ret < 0)
2367 		goto hw_free;
2368 
2369 	/* run the stream event for each BE */
2370 	dpcm_dapm_stream_event(fe, stream, SND_SOC_DAPM_STREAM_NOP);
2371 
2372 	/* keep going if FE state is > prepare */
2373 	if (fe->dpcm[stream].state == SND_SOC_DPCM_STATE_PREPARE ||
2374 		fe->dpcm[stream].state == SND_SOC_DPCM_STATE_STOP)
2375 		return 0;
2376 
2377 	if (trigger == SND_SOC_DPCM_TRIGGER_BESPOKE) {
2378 		/* call trigger on the frontend - FE takes care of all BE triggers */
2379 		dev_dbg(fe->dev, "ASoC: bespoke trigger FE %s cmd start\n",
2380 				fe->dai_link->name);
2381 
2382 		ret = soc_pcm_bespoke_trigger(substream, SNDRV_PCM_TRIGGER_START);
2383 		if (ret < 0) {
2384 			dev_err(fe->dev,"ASoC: bespoke trigger FE failed %d\n", ret);
2385 			goto hw_free;
2386 		}
2387 	} else {
2388 		dev_dbg(fe->dev, "ASoC: trigger FE %s cmd start\n",
2389 			fe->dai_link->name);
2390 
2391 		ret = dpcm_be_dai_trigger(fe, stream,
2392 					SNDRV_PCM_TRIGGER_START);
2393 		if (ret < 0) {
2394 			dev_err(fe->dev,"ASoC: trigger FE failed %d\n", ret);
2395 			goto hw_free;
2396 		}
2397 	}
2398 
2399 	return 0;
2400 
2401 hw_free:
2402 	dpcm_be_dai_hw_free(fe, stream);
2403 close:
2404 	dpcm_be_dai_shutdown(fe, stream);
2405 disconnect:
2406 	/* disconnect any non started BEs */
2407 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
2408 		struct snd_soc_pcm_runtime *be = dpcm->be;
2409 		if (be->dpcm[stream].state != SND_SOC_DPCM_STATE_START)
2410 				dpcm->state = SND_SOC_DPCM_LINK_STATE_FREE;
2411 	}
2412 
2413 	return ret;
2414 }
2415 
2416 static int dpcm_run_new_update(struct snd_soc_pcm_runtime *fe, int stream)
2417 {
2418 	int ret;
2419 
2420 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_BE);
2421 	ret = dpcm_run_update_startup(fe, stream);
2422 	if (ret < 0)
2423 		dev_err(fe->dev, "ASoC: failed to startup some BEs\n");
2424 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_NO);
2425 
2426 	return ret;
2427 }
2428 
2429 static int dpcm_run_old_update(struct snd_soc_pcm_runtime *fe, int stream)
2430 {
2431 	int ret;
2432 
2433 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_BE);
2434 	ret = dpcm_run_update_shutdown(fe, stream);
2435 	if (ret < 0)
2436 		dev_err(fe->dev, "ASoC: failed to shutdown some BEs\n");
2437 	dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_NO);
2438 
2439 	return ret;
2440 }
2441 
2442 /* Called by DAPM mixer/mux changes to update audio routing between PCMs and
2443  * any DAI links.
2444  */
2445 int soc_dpcm_runtime_update(struct snd_soc_card *card)
2446 {
2447 	struct snd_soc_pcm_runtime *fe;
2448 	int old, new, paths;
2449 
2450 	mutex_lock_nested(&card->mutex, SND_SOC_CARD_CLASS_RUNTIME);
2451 	list_for_each_entry(fe, &card->rtd_list, list) {
2452 		struct snd_soc_dapm_widget_list *list;
2453 
2454 		/* make sure link is FE */
2455 		if (!fe->dai_link->dynamic)
2456 			continue;
2457 
2458 		/* only check active links */
2459 		if (!fe->cpu_dai->active)
2460 			continue;
2461 
2462 		/* DAPM sync will call this to update DSP paths */
2463 		dev_dbg(fe->dev, "ASoC: DPCM runtime update for FE %s\n",
2464 			fe->dai_link->name);
2465 
2466 		/* skip if FE doesn't have playback capability */
2467 		if (!fe->cpu_dai->driver->playback.channels_min
2468 		    || !fe->codec_dai->driver->playback.channels_min)
2469 			goto capture;
2470 
2471 		/* skip if FE isn't currently playing */
2472 		if (!fe->cpu_dai->playback_active
2473 		    || !fe->codec_dai->playback_active)
2474 			goto capture;
2475 
2476 		paths = dpcm_path_get(fe, SNDRV_PCM_STREAM_PLAYBACK, &list);
2477 		if (paths < 0) {
2478 			dev_warn(fe->dev, "ASoC: %s no valid %s path\n",
2479 					fe->dai_link->name,  "playback");
2480 			mutex_unlock(&card->mutex);
2481 			return paths;
2482 		}
2483 
2484 		/* update any new playback paths */
2485 		new = dpcm_process_paths(fe, SNDRV_PCM_STREAM_PLAYBACK, &list, 1);
2486 		if (new) {
2487 			dpcm_run_new_update(fe, SNDRV_PCM_STREAM_PLAYBACK);
2488 			dpcm_clear_pending_state(fe, SNDRV_PCM_STREAM_PLAYBACK);
2489 			dpcm_be_disconnect(fe, SNDRV_PCM_STREAM_PLAYBACK);
2490 		}
2491 
2492 		/* update any old playback paths */
2493 		old = dpcm_process_paths(fe, SNDRV_PCM_STREAM_PLAYBACK, &list, 0);
2494 		if (old) {
2495 			dpcm_run_old_update(fe, SNDRV_PCM_STREAM_PLAYBACK);
2496 			dpcm_clear_pending_state(fe, SNDRV_PCM_STREAM_PLAYBACK);
2497 			dpcm_be_disconnect(fe, SNDRV_PCM_STREAM_PLAYBACK);
2498 		}
2499 
2500 		dpcm_path_put(&list);
2501 capture:
2502 		/* skip if FE doesn't have capture capability */
2503 		if (!fe->cpu_dai->driver->capture.channels_min
2504 		    || !fe->codec_dai->driver->capture.channels_min)
2505 			continue;
2506 
2507 		/* skip if FE isn't currently capturing */
2508 		if (!fe->cpu_dai->capture_active
2509 		    || !fe->codec_dai->capture_active)
2510 			continue;
2511 
2512 		paths = dpcm_path_get(fe, SNDRV_PCM_STREAM_CAPTURE, &list);
2513 		if (paths < 0) {
2514 			dev_warn(fe->dev, "ASoC: %s no valid %s path\n",
2515 					fe->dai_link->name,  "capture");
2516 			mutex_unlock(&card->mutex);
2517 			return paths;
2518 		}
2519 
2520 		/* update any new capture paths */
2521 		new = dpcm_process_paths(fe, SNDRV_PCM_STREAM_CAPTURE, &list, 1);
2522 		if (new) {
2523 			dpcm_run_new_update(fe, SNDRV_PCM_STREAM_CAPTURE);
2524 			dpcm_clear_pending_state(fe, SNDRV_PCM_STREAM_CAPTURE);
2525 			dpcm_be_disconnect(fe, SNDRV_PCM_STREAM_CAPTURE);
2526 		}
2527 
2528 		/* update any old capture paths */
2529 		old = dpcm_process_paths(fe, SNDRV_PCM_STREAM_CAPTURE, &list, 0);
2530 		if (old) {
2531 			dpcm_run_old_update(fe, SNDRV_PCM_STREAM_CAPTURE);
2532 			dpcm_clear_pending_state(fe, SNDRV_PCM_STREAM_CAPTURE);
2533 			dpcm_be_disconnect(fe, SNDRV_PCM_STREAM_CAPTURE);
2534 		}
2535 
2536 		dpcm_path_put(&list);
2537 	}
2538 
2539 	mutex_unlock(&card->mutex);
2540 	return 0;
2541 }
2542 int soc_dpcm_be_digital_mute(struct snd_soc_pcm_runtime *fe, int mute)
2543 {
2544 	struct snd_soc_dpcm *dpcm;
2545 	struct list_head *clients =
2546 		&fe->dpcm[SNDRV_PCM_STREAM_PLAYBACK].be_clients;
2547 
2548 	list_for_each_entry(dpcm, clients, list_be) {
2549 
2550 		struct snd_soc_pcm_runtime *be = dpcm->be;
2551 		int i;
2552 
2553 		if (be->dai_link->ignore_suspend)
2554 			continue;
2555 
2556 		for (i = 0; i < be->num_codecs; i++) {
2557 			struct snd_soc_dai *dai = be->codec_dais[i];
2558 			struct snd_soc_dai_driver *drv = dai->driver;
2559 
2560 			dev_dbg(be->dev, "ASoC: BE digital mute %s\n",
2561 					 be->dai_link->name);
2562 
2563 			if (drv->ops && drv->ops->digital_mute &&
2564 							dai->playback_active)
2565 				drv->ops->digital_mute(dai, mute);
2566 		}
2567 	}
2568 
2569 	return 0;
2570 }
2571 
2572 static int dpcm_fe_dai_open(struct snd_pcm_substream *fe_substream)
2573 {
2574 	struct snd_soc_pcm_runtime *fe = fe_substream->private_data;
2575 	struct snd_soc_dpcm *dpcm;
2576 	struct snd_soc_dapm_widget_list *list;
2577 	int ret;
2578 	int stream = fe_substream->stream;
2579 
2580 	mutex_lock_nested(&fe->card->mutex, SND_SOC_CARD_CLASS_RUNTIME);
2581 	fe->dpcm[stream].runtime = fe_substream->runtime;
2582 
2583 	ret = dpcm_path_get(fe, stream, &list);
2584 	if (ret < 0) {
2585 		mutex_unlock(&fe->card->mutex);
2586 		return ret;
2587 	} else if (ret == 0) {
2588 		dev_dbg(fe->dev, "ASoC: %s no valid %s route\n",
2589 			fe->dai_link->name, stream ? "capture" : "playback");
2590 	}
2591 
2592 	/* calculate valid and active FE <-> BE dpcms */
2593 	dpcm_process_paths(fe, stream, &list, 1);
2594 
2595 	ret = dpcm_fe_dai_startup(fe_substream);
2596 	if (ret < 0) {
2597 		/* clean up all links */
2598 		list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be)
2599 			dpcm->state = SND_SOC_DPCM_LINK_STATE_FREE;
2600 
2601 		dpcm_be_disconnect(fe, stream);
2602 		fe->dpcm[stream].runtime = NULL;
2603 	}
2604 
2605 	dpcm_clear_pending_state(fe, stream);
2606 	dpcm_path_put(&list);
2607 	mutex_unlock(&fe->card->mutex);
2608 	return ret;
2609 }
2610 
2611 static int dpcm_fe_dai_close(struct snd_pcm_substream *fe_substream)
2612 {
2613 	struct snd_soc_pcm_runtime *fe = fe_substream->private_data;
2614 	struct snd_soc_dpcm *dpcm;
2615 	int stream = fe_substream->stream, ret;
2616 
2617 	mutex_lock_nested(&fe->card->mutex, SND_SOC_CARD_CLASS_RUNTIME);
2618 	ret = dpcm_fe_dai_shutdown(fe_substream);
2619 
2620 	/* mark FE's links ready to prune */
2621 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be)
2622 		dpcm->state = SND_SOC_DPCM_LINK_STATE_FREE;
2623 
2624 	dpcm_be_disconnect(fe, stream);
2625 
2626 	fe->dpcm[stream].runtime = NULL;
2627 	mutex_unlock(&fe->card->mutex);
2628 	return ret;
2629 }
2630 
2631 static void soc_pcm_free(struct snd_pcm *pcm)
2632 {
2633 	struct snd_soc_pcm_runtime *rtd = pcm->private_data;
2634 	struct snd_soc_component *component;
2635 
2636 	list_for_each_entry(component, &rtd->card->component_dev_list,
2637 			    card_list) {
2638 		if (component->pcm_free)
2639 			component->pcm_free(pcm);
2640 	}
2641 }
2642 
2643 /* create a new pcm */
2644 int soc_new_pcm(struct snd_soc_pcm_runtime *rtd, int num)
2645 {
2646 	struct snd_soc_platform *platform = rtd->platform;
2647 	struct snd_soc_dai *codec_dai;
2648 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
2649 	struct snd_soc_component *component;
2650 	struct snd_pcm *pcm;
2651 	char new_name[64];
2652 	int ret = 0, playback = 0, capture = 0;
2653 	int i;
2654 
2655 	if (rtd->dai_link->dynamic || rtd->dai_link->no_pcm) {
2656 		playback = rtd->dai_link->dpcm_playback;
2657 		capture = rtd->dai_link->dpcm_capture;
2658 	} else {
2659 		for (i = 0; i < rtd->num_codecs; i++) {
2660 			codec_dai = rtd->codec_dais[i];
2661 			if (codec_dai->driver->playback.channels_min)
2662 				playback = 1;
2663 			if (codec_dai->driver->capture.channels_min)
2664 				capture = 1;
2665 		}
2666 
2667 		capture = capture && cpu_dai->driver->capture.channels_min;
2668 		playback = playback && cpu_dai->driver->playback.channels_min;
2669 	}
2670 
2671 	if (rtd->dai_link->playback_only) {
2672 		playback = 1;
2673 		capture = 0;
2674 	}
2675 
2676 	if (rtd->dai_link->capture_only) {
2677 		playback = 0;
2678 		capture = 1;
2679 	}
2680 
2681 	/* create the PCM */
2682 	if (rtd->dai_link->no_pcm) {
2683 		snprintf(new_name, sizeof(new_name), "(%s)",
2684 			rtd->dai_link->stream_name);
2685 
2686 		ret = snd_pcm_new_internal(rtd->card->snd_card, new_name, num,
2687 				playback, capture, &pcm);
2688 	} else {
2689 		if (rtd->dai_link->dynamic)
2690 			snprintf(new_name, sizeof(new_name), "%s (*)",
2691 				rtd->dai_link->stream_name);
2692 		else
2693 			snprintf(new_name, sizeof(new_name), "%s %s-%d",
2694 				rtd->dai_link->stream_name,
2695 				(rtd->num_codecs > 1) ?
2696 				"multicodec" : rtd->codec_dai->name, num);
2697 
2698 		ret = snd_pcm_new(rtd->card->snd_card, new_name, num, playback,
2699 			capture, &pcm);
2700 	}
2701 	if (ret < 0) {
2702 		dev_err(rtd->card->dev, "ASoC: can't create pcm for %s\n",
2703 			rtd->dai_link->name);
2704 		return ret;
2705 	}
2706 	dev_dbg(rtd->card->dev, "ASoC: registered pcm #%d %s\n",num, new_name);
2707 
2708 	/* DAPM dai link stream work */
2709 	INIT_DELAYED_WORK(&rtd->delayed_work, close_delayed_work);
2710 
2711 	pcm->nonatomic = rtd->dai_link->nonatomic;
2712 	rtd->pcm = pcm;
2713 	pcm->private_data = rtd;
2714 
2715 	if (rtd->dai_link->no_pcm) {
2716 		if (playback)
2717 			pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->private_data = rtd;
2718 		if (capture)
2719 			pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream->private_data = rtd;
2720 		goto out;
2721 	}
2722 
2723 	/* ASoC PCM operations */
2724 	if (rtd->dai_link->dynamic) {
2725 		rtd->ops.open		= dpcm_fe_dai_open;
2726 		rtd->ops.hw_params	= dpcm_fe_dai_hw_params;
2727 		rtd->ops.prepare	= dpcm_fe_dai_prepare;
2728 		rtd->ops.trigger	= dpcm_fe_dai_trigger;
2729 		rtd->ops.hw_free	= dpcm_fe_dai_hw_free;
2730 		rtd->ops.close		= dpcm_fe_dai_close;
2731 		rtd->ops.pointer	= soc_pcm_pointer;
2732 		rtd->ops.ioctl		= soc_pcm_ioctl;
2733 	} else {
2734 		rtd->ops.open		= soc_pcm_open;
2735 		rtd->ops.hw_params	= soc_pcm_hw_params;
2736 		rtd->ops.prepare	= soc_pcm_prepare;
2737 		rtd->ops.trigger	= soc_pcm_trigger;
2738 		rtd->ops.hw_free	= soc_pcm_hw_free;
2739 		rtd->ops.close		= soc_pcm_close;
2740 		rtd->ops.pointer	= soc_pcm_pointer;
2741 		rtd->ops.ioctl		= soc_pcm_ioctl;
2742 	}
2743 
2744 	if (platform->driver->ops) {
2745 		rtd->ops.ack		= platform->driver->ops->ack;
2746 		rtd->ops.copy		= platform->driver->ops->copy;
2747 		rtd->ops.silence	= platform->driver->ops->silence;
2748 		rtd->ops.page		= platform->driver->ops->page;
2749 		rtd->ops.mmap		= platform->driver->ops->mmap;
2750 	}
2751 
2752 	if (playback)
2753 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &rtd->ops);
2754 
2755 	if (capture)
2756 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &rtd->ops);
2757 
2758 	list_for_each_entry(component, &rtd->card->component_dev_list, card_list) {
2759 		if (component->pcm_new) {
2760 			ret = component->pcm_new(rtd);
2761 			if (ret < 0) {
2762 				dev_err(component->dev,
2763 					"ASoC: pcm constructor failed: %d\n",
2764 					ret);
2765 				return ret;
2766 			}
2767 		}
2768 	}
2769 	pcm->private_free = soc_pcm_free;
2770 out:
2771 	dev_info(rtd->card->dev, "%s <-> %s mapping ok\n",
2772 		 (rtd->num_codecs > 1) ? "multicodec" : rtd->codec_dai->name,
2773 		 cpu_dai->name);
2774 	return ret;
2775 }
2776 
2777 /* is the current PCM operation for this FE ? */
2778 int snd_soc_dpcm_fe_can_update(struct snd_soc_pcm_runtime *fe, int stream)
2779 {
2780 	if (fe->dpcm[stream].runtime_update == SND_SOC_DPCM_UPDATE_FE)
2781 		return 1;
2782 	return 0;
2783 }
2784 EXPORT_SYMBOL_GPL(snd_soc_dpcm_fe_can_update);
2785 
2786 /* is the current PCM operation for this BE ? */
2787 int snd_soc_dpcm_be_can_update(struct snd_soc_pcm_runtime *fe,
2788 		struct snd_soc_pcm_runtime *be, int stream)
2789 {
2790 	if ((fe->dpcm[stream].runtime_update == SND_SOC_DPCM_UPDATE_FE) ||
2791 	   ((fe->dpcm[stream].runtime_update == SND_SOC_DPCM_UPDATE_BE) &&
2792 		  be->dpcm[stream].runtime_update))
2793 		return 1;
2794 	return 0;
2795 }
2796 EXPORT_SYMBOL_GPL(snd_soc_dpcm_be_can_update);
2797 
2798 /* get the substream for this BE */
2799 struct snd_pcm_substream *
2800 	snd_soc_dpcm_get_substream(struct snd_soc_pcm_runtime *be, int stream)
2801 {
2802 	return be->pcm->streams[stream].substream;
2803 }
2804 EXPORT_SYMBOL_GPL(snd_soc_dpcm_get_substream);
2805 
2806 /* get the BE runtime state */
2807 enum snd_soc_dpcm_state
2808 	snd_soc_dpcm_be_get_state(struct snd_soc_pcm_runtime *be, int stream)
2809 {
2810 	return be->dpcm[stream].state;
2811 }
2812 EXPORT_SYMBOL_GPL(snd_soc_dpcm_be_get_state);
2813 
2814 /* set the BE runtime state */
2815 void snd_soc_dpcm_be_set_state(struct snd_soc_pcm_runtime *be,
2816 		int stream, enum snd_soc_dpcm_state state)
2817 {
2818 	be->dpcm[stream].state = state;
2819 }
2820 EXPORT_SYMBOL_GPL(snd_soc_dpcm_be_set_state);
2821 
2822 /*
2823  * We can only hw_free, stop, pause or suspend a BE DAI if any of it's FE
2824  * are not running, paused or suspended for the specified stream direction.
2825  */
2826 int snd_soc_dpcm_can_be_free_stop(struct snd_soc_pcm_runtime *fe,
2827 		struct snd_soc_pcm_runtime *be, int stream)
2828 {
2829 	struct snd_soc_dpcm *dpcm;
2830 	int state;
2831 
2832 	list_for_each_entry(dpcm, &be->dpcm[stream].fe_clients, list_fe) {
2833 
2834 		if (dpcm->fe == fe)
2835 			continue;
2836 
2837 		state = dpcm->fe->dpcm[stream].state;
2838 		if (state == SND_SOC_DPCM_STATE_START ||
2839 			state == SND_SOC_DPCM_STATE_PAUSED ||
2840 			state == SND_SOC_DPCM_STATE_SUSPEND)
2841 			return 0;
2842 	}
2843 
2844 	/* it's safe to free/stop this BE DAI */
2845 	return 1;
2846 }
2847 EXPORT_SYMBOL_GPL(snd_soc_dpcm_can_be_free_stop);
2848 
2849 /*
2850  * We can only change hw params a BE DAI if any of it's FE are not prepared,
2851  * running, paused or suspended for the specified stream direction.
2852  */
2853 int snd_soc_dpcm_can_be_params(struct snd_soc_pcm_runtime *fe,
2854 		struct snd_soc_pcm_runtime *be, int stream)
2855 {
2856 	struct snd_soc_dpcm *dpcm;
2857 	int state;
2858 
2859 	list_for_each_entry(dpcm, &be->dpcm[stream].fe_clients, list_fe) {
2860 
2861 		if (dpcm->fe == fe)
2862 			continue;
2863 
2864 		state = dpcm->fe->dpcm[stream].state;
2865 		if (state == SND_SOC_DPCM_STATE_START ||
2866 			state == SND_SOC_DPCM_STATE_PAUSED ||
2867 			state == SND_SOC_DPCM_STATE_SUSPEND ||
2868 			state == SND_SOC_DPCM_STATE_PREPARE)
2869 			return 0;
2870 	}
2871 
2872 	/* it's safe to change hw_params */
2873 	return 1;
2874 }
2875 EXPORT_SYMBOL_GPL(snd_soc_dpcm_can_be_params);
2876 
2877 #ifdef CONFIG_DEBUG_FS
2878 static const char *dpcm_state_string(enum snd_soc_dpcm_state state)
2879 {
2880 	switch (state) {
2881 	case SND_SOC_DPCM_STATE_NEW:
2882 		return "new";
2883 	case SND_SOC_DPCM_STATE_OPEN:
2884 		return "open";
2885 	case SND_SOC_DPCM_STATE_HW_PARAMS:
2886 		return "hw_params";
2887 	case SND_SOC_DPCM_STATE_PREPARE:
2888 		return "prepare";
2889 	case SND_SOC_DPCM_STATE_START:
2890 		return "start";
2891 	case SND_SOC_DPCM_STATE_STOP:
2892 		return "stop";
2893 	case SND_SOC_DPCM_STATE_SUSPEND:
2894 		return "suspend";
2895 	case SND_SOC_DPCM_STATE_PAUSED:
2896 		return "paused";
2897 	case SND_SOC_DPCM_STATE_HW_FREE:
2898 		return "hw_free";
2899 	case SND_SOC_DPCM_STATE_CLOSE:
2900 		return "close";
2901 	}
2902 
2903 	return "unknown";
2904 }
2905 
2906 static ssize_t dpcm_show_state(struct snd_soc_pcm_runtime *fe,
2907 				int stream, char *buf, size_t size)
2908 {
2909 	struct snd_pcm_hw_params *params = &fe->dpcm[stream].hw_params;
2910 	struct snd_soc_dpcm *dpcm;
2911 	ssize_t offset = 0;
2912 
2913 	/* FE state */
2914 	offset += snprintf(buf + offset, size - offset,
2915 			"[%s - %s]\n", fe->dai_link->name,
2916 			stream ? "Capture" : "Playback");
2917 
2918 	offset += snprintf(buf + offset, size - offset, "State: %s\n",
2919 	                dpcm_state_string(fe->dpcm[stream].state));
2920 
2921 	if ((fe->dpcm[stream].state >= SND_SOC_DPCM_STATE_HW_PARAMS) &&
2922 	    (fe->dpcm[stream].state <= SND_SOC_DPCM_STATE_STOP))
2923 		offset += snprintf(buf + offset, size - offset,
2924 				"Hardware Params: "
2925 				"Format = %s, Channels = %d, Rate = %d\n",
2926 				snd_pcm_format_name(params_format(params)),
2927 				params_channels(params),
2928 				params_rate(params));
2929 
2930 	/* BEs state */
2931 	offset += snprintf(buf + offset, size - offset, "Backends:\n");
2932 
2933 	if (list_empty(&fe->dpcm[stream].be_clients)) {
2934 		offset += snprintf(buf + offset, size - offset,
2935 				" No active DSP links\n");
2936 		goto out;
2937 	}
2938 
2939 	list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
2940 		struct snd_soc_pcm_runtime *be = dpcm->be;
2941 		params = &dpcm->hw_params;
2942 
2943 		offset += snprintf(buf + offset, size - offset,
2944 				"- %s\n", be->dai_link->name);
2945 
2946 		offset += snprintf(buf + offset, size - offset,
2947 				"   State: %s\n",
2948 				dpcm_state_string(be->dpcm[stream].state));
2949 
2950 		if ((be->dpcm[stream].state >= SND_SOC_DPCM_STATE_HW_PARAMS) &&
2951 		    (be->dpcm[stream].state <= SND_SOC_DPCM_STATE_STOP))
2952 			offset += snprintf(buf + offset, size - offset,
2953 				"   Hardware Params: "
2954 				"Format = %s, Channels = %d, Rate = %d\n",
2955 				snd_pcm_format_name(params_format(params)),
2956 				params_channels(params),
2957 				params_rate(params));
2958 	}
2959 
2960 out:
2961 	return offset;
2962 }
2963 
2964 static ssize_t dpcm_state_read_file(struct file *file, char __user *user_buf,
2965 				size_t count, loff_t *ppos)
2966 {
2967 	struct snd_soc_pcm_runtime *fe = file->private_data;
2968 	ssize_t out_count = PAGE_SIZE, offset = 0, ret = 0;
2969 	char *buf;
2970 
2971 	buf = kmalloc(out_count, GFP_KERNEL);
2972 	if (!buf)
2973 		return -ENOMEM;
2974 
2975 	if (fe->cpu_dai->driver->playback.channels_min)
2976 		offset += dpcm_show_state(fe, SNDRV_PCM_STREAM_PLAYBACK,
2977 					buf + offset, out_count - offset);
2978 
2979 	if (fe->cpu_dai->driver->capture.channels_min)
2980 		offset += dpcm_show_state(fe, SNDRV_PCM_STREAM_CAPTURE,
2981 					buf + offset, out_count - offset);
2982 
2983 	ret = simple_read_from_buffer(user_buf, count, ppos, buf, offset);
2984 
2985 	kfree(buf);
2986 	return ret;
2987 }
2988 
2989 static const struct file_operations dpcm_state_fops = {
2990 	.open = simple_open,
2991 	.read = dpcm_state_read_file,
2992 	.llseek = default_llseek,
2993 };
2994 
2995 void soc_dpcm_debugfs_add(struct snd_soc_pcm_runtime *rtd)
2996 {
2997 	if (!rtd->dai_link)
2998 		return;
2999 
3000 	if (!rtd->card->debugfs_card_root)
3001 		return;
3002 
3003 	rtd->debugfs_dpcm_root = debugfs_create_dir(rtd->dai_link->name,
3004 			rtd->card->debugfs_card_root);
3005 	if (!rtd->debugfs_dpcm_root) {
3006 		dev_dbg(rtd->dev,
3007 			 "ASoC: Failed to create dpcm debugfs directory %s\n",
3008 			 rtd->dai_link->name);
3009 		return;
3010 	}
3011 
3012 	rtd->debugfs_dpcm_state = debugfs_create_file("state", 0444,
3013 						rtd->debugfs_dpcm_root,
3014 						rtd, &dpcm_state_fops);
3015 }
3016 #endif
3017