xref: /openbmc/linux/sound/soc/soc-core.c (revision b627b4ed)
1 /*
2  * soc-core.c  --  ALSA SoC Audio Layer
3  *
4  * Copyright 2005 Wolfson Microelectronics PLC.
5  * Copyright 2005 Openedhand Ltd.
6  *
7  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
8  *         with code, comments and ideas from :-
9  *         Richard Purdie <richard@openedhand.com>
10  *
11  *  This program is free software; you can redistribute  it and/or modify it
12  *  under  the terms of  the GNU General  Public License as published by the
13  *  Free Software Foundation;  either version 2 of the  License, or (at your
14  *  option) any later version.
15  *
16  *  TODO:
17  *   o Add hw rules to enforce rates, etc.
18  *   o More testing with other codecs/machines.
19  *   o Add more codecs and platforms to ensure good API coverage.
20  *   o Support TDM on PCM and I2S
21  */
22 
23 #include <linux/module.h>
24 #include <linux/moduleparam.h>
25 #include <linux/init.h>
26 #include <linux/delay.h>
27 #include <linux/pm.h>
28 #include <linux/bitops.h>
29 #include <linux/debugfs.h>
30 #include <linux/platform_device.h>
31 #include <sound/core.h>
32 #include <sound/pcm.h>
33 #include <sound/pcm_params.h>
34 #include <sound/soc.h>
35 #include <sound/soc-dapm.h>
36 #include <sound/initval.h>
37 
38 static DEFINE_MUTEX(pcm_mutex);
39 static DEFINE_MUTEX(io_mutex);
40 static DECLARE_WAIT_QUEUE_HEAD(soc_pm_waitq);
41 
42 #ifdef CONFIG_DEBUG_FS
43 static struct dentry *debugfs_root;
44 #endif
45 
46 static DEFINE_MUTEX(client_mutex);
47 static LIST_HEAD(card_list);
48 static LIST_HEAD(dai_list);
49 static LIST_HEAD(platform_list);
50 static LIST_HEAD(codec_list);
51 
52 static int snd_soc_register_card(struct snd_soc_card *card);
53 static int snd_soc_unregister_card(struct snd_soc_card *card);
54 
55 /*
56  * This is a timeout to do a DAPM powerdown after a stream is closed().
57  * It can be used to eliminate pops between different playback streams, e.g.
58  * between two audio tracks.
59  */
60 static int pmdown_time = 5000;
61 module_param(pmdown_time, int, 0);
62 MODULE_PARM_DESC(pmdown_time, "DAPM stream powerdown time (msecs)");
63 
64 /*
65  * This function forces any delayed work to be queued and run.
66  */
67 static int run_delayed_work(struct delayed_work *dwork)
68 {
69 	int ret;
70 
71 	/* cancel any work waiting to be queued. */
72 	ret = cancel_delayed_work(dwork);
73 
74 	/* if there was any work waiting then we run it now and
75 	 * wait for it's completion */
76 	if (ret) {
77 		schedule_delayed_work(dwork, 0);
78 		flush_scheduled_work();
79 	}
80 	return ret;
81 }
82 
83 #ifdef CONFIG_SND_SOC_AC97_BUS
84 /* unregister ac97 codec */
85 static int soc_ac97_dev_unregister(struct snd_soc_codec *codec)
86 {
87 	if (codec->ac97->dev.bus)
88 		device_unregister(&codec->ac97->dev);
89 	return 0;
90 }
91 
92 /* stop no dev release warning */
93 static void soc_ac97_device_release(struct device *dev){}
94 
95 /* register ac97 codec to bus */
96 static int soc_ac97_dev_register(struct snd_soc_codec *codec)
97 {
98 	int err;
99 
100 	codec->ac97->dev.bus = &ac97_bus_type;
101 	codec->ac97->dev.parent = codec->card->dev;
102 	codec->ac97->dev.release = soc_ac97_device_release;
103 
104 	dev_set_name(&codec->ac97->dev, "%d-%d:%s",
105 		     codec->card->number, 0, codec->name);
106 	err = device_register(&codec->ac97->dev);
107 	if (err < 0) {
108 		snd_printk(KERN_ERR "Can't register ac97 bus\n");
109 		codec->ac97->dev.bus = NULL;
110 		return err;
111 	}
112 	return 0;
113 }
114 #endif
115 
116 /*
117  * Called by ALSA when a PCM substream is opened, the runtime->hw record is
118  * then initialized and any private data can be allocated. This also calls
119  * startup for the cpu DAI, platform, machine and codec DAI.
120  */
121 static int soc_pcm_open(struct snd_pcm_substream *substream)
122 {
123 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
124 	struct snd_soc_device *socdev = rtd->socdev;
125 	struct snd_soc_card *card = socdev->card;
126 	struct snd_pcm_runtime *runtime = substream->runtime;
127 	struct snd_soc_dai_link *machine = rtd->dai;
128 	struct snd_soc_platform *platform = card->platform;
129 	struct snd_soc_dai *cpu_dai = machine->cpu_dai;
130 	struct snd_soc_dai *codec_dai = machine->codec_dai;
131 	int ret = 0;
132 
133 	mutex_lock(&pcm_mutex);
134 
135 	/* startup the audio subsystem */
136 	if (cpu_dai->ops->startup) {
137 		ret = cpu_dai->ops->startup(substream, cpu_dai);
138 		if (ret < 0) {
139 			printk(KERN_ERR "asoc: can't open interface %s\n",
140 				cpu_dai->name);
141 			goto out;
142 		}
143 	}
144 
145 	if (platform->pcm_ops->open) {
146 		ret = platform->pcm_ops->open(substream);
147 		if (ret < 0) {
148 			printk(KERN_ERR "asoc: can't open platform %s\n", platform->name);
149 			goto platform_err;
150 		}
151 	}
152 
153 	if (codec_dai->ops->startup) {
154 		ret = codec_dai->ops->startup(substream, codec_dai);
155 		if (ret < 0) {
156 			printk(KERN_ERR "asoc: can't open codec %s\n",
157 				codec_dai->name);
158 			goto codec_dai_err;
159 		}
160 	}
161 
162 	if (machine->ops && machine->ops->startup) {
163 		ret = machine->ops->startup(substream);
164 		if (ret < 0) {
165 			printk(KERN_ERR "asoc: %s startup failed\n", machine->name);
166 			goto machine_err;
167 		}
168 	}
169 
170 	/* Check that the codec and cpu DAI's are compatible */
171 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
172 		runtime->hw.rate_min =
173 			max(codec_dai->playback.rate_min,
174 			    cpu_dai->playback.rate_min);
175 		runtime->hw.rate_max =
176 			min(codec_dai->playback.rate_max,
177 			    cpu_dai->playback.rate_max);
178 		runtime->hw.channels_min =
179 			max(codec_dai->playback.channels_min,
180 				cpu_dai->playback.channels_min);
181 		runtime->hw.channels_max =
182 			min(codec_dai->playback.channels_max,
183 				cpu_dai->playback.channels_max);
184 		runtime->hw.formats =
185 			codec_dai->playback.formats & cpu_dai->playback.formats;
186 		runtime->hw.rates =
187 			codec_dai->playback.rates & cpu_dai->playback.rates;
188 	} else {
189 		runtime->hw.rate_min =
190 			max(codec_dai->capture.rate_min,
191 			    cpu_dai->capture.rate_min);
192 		runtime->hw.rate_max =
193 			min(codec_dai->capture.rate_max,
194 			    cpu_dai->capture.rate_max);
195 		runtime->hw.channels_min =
196 			max(codec_dai->capture.channels_min,
197 				cpu_dai->capture.channels_min);
198 		runtime->hw.channels_max =
199 			min(codec_dai->capture.channels_max,
200 				cpu_dai->capture.channels_max);
201 		runtime->hw.formats =
202 			codec_dai->capture.formats & cpu_dai->capture.formats;
203 		runtime->hw.rates =
204 			codec_dai->capture.rates & cpu_dai->capture.rates;
205 	}
206 
207 	snd_pcm_limit_hw_rates(runtime);
208 	if (!runtime->hw.rates) {
209 		printk(KERN_ERR "asoc: %s <-> %s No matching rates\n",
210 			codec_dai->name, cpu_dai->name);
211 		goto machine_err;
212 	}
213 	if (!runtime->hw.formats) {
214 		printk(KERN_ERR "asoc: %s <-> %s No matching formats\n",
215 			codec_dai->name, cpu_dai->name);
216 		goto machine_err;
217 	}
218 	if (!runtime->hw.channels_min || !runtime->hw.channels_max) {
219 		printk(KERN_ERR "asoc: %s <-> %s No matching channels\n",
220 			codec_dai->name, cpu_dai->name);
221 		goto machine_err;
222 	}
223 
224 	pr_debug("asoc: %s <-> %s info:\n", codec_dai->name, cpu_dai->name);
225 	pr_debug("asoc: rate mask 0x%x\n", runtime->hw.rates);
226 	pr_debug("asoc: min ch %d max ch %d\n", runtime->hw.channels_min,
227 		 runtime->hw.channels_max);
228 	pr_debug("asoc: min rate %d max rate %d\n", runtime->hw.rate_min,
229 		 runtime->hw.rate_max);
230 
231 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
232 		cpu_dai->playback.active = codec_dai->playback.active = 1;
233 	else
234 		cpu_dai->capture.active = codec_dai->capture.active = 1;
235 	cpu_dai->active = codec_dai->active = 1;
236 	cpu_dai->runtime = runtime;
237 	card->codec->active++;
238 	mutex_unlock(&pcm_mutex);
239 	return 0;
240 
241 machine_err:
242 	if (machine->ops && machine->ops->shutdown)
243 		machine->ops->shutdown(substream);
244 
245 codec_dai_err:
246 	if (platform->pcm_ops->close)
247 		platform->pcm_ops->close(substream);
248 
249 platform_err:
250 	if (cpu_dai->ops->shutdown)
251 		cpu_dai->ops->shutdown(substream, cpu_dai);
252 out:
253 	mutex_unlock(&pcm_mutex);
254 	return ret;
255 }
256 
257 /*
258  * Power down the audio subsystem pmdown_time msecs after close is called.
259  * This is to ensure there are no pops or clicks in between any music tracks
260  * due to DAPM power cycling.
261  */
262 static void close_delayed_work(struct work_struct *work)
263 {
264 	struct snd_soc_card *card = container_of(work, struct snd_soc_card,
265 						 delayed_work.work);
266 	struct snd_soc_device *socdev = card->socdev;
267 	struct snd_soc_codec *codec = card->codec;
268 	struct snd_soc_dai *codec_dai;
269 	int i;
270 
271 	mutex_lock(&pcm_mutex);
272 	for (i = 0; i < codec->num_dai; i++) {
273 		codec_dai = &codec->dai[i];
274 
275 		pr_debug("pop wq checking: %s status: %s waiting: %s\n",
276 			 codec_dai->playback.stream_name,
277 			 codec_dai->playback.active ? "active" : "inactive",
278 			 codec_dai->pop_wait ? "yes" : "no");
279 
280 		/* are we waiting on this codec DAI stream */
281 		if (codec_dai->pop_wait == 1) {
282 
283 			/* Reduce power if no longer active */
284 			if (codec->active == 0) {
285 				pr_debug("pop wq D1 %s %s\n", codec->name,
286 					 codec_dai->playback.stream_name);
287 				snd_soc_dapm_set_bias_level(socdev,
288 					SND_SOC_BIAS_PREPARE);
289 			}
290 
291 			codec_dai->pop_wait = 0;
292 			snd_soc_dapm_stream_event(codec,
293 				codec_dai->playback.stream_name,
294 				SND_SOC_DAPM_STREAM_STOP);
295 
296 			/* Fall into standby if no longer active */
297 			if (codec->active == 0) {
298 				pr_debug("pop wq D3 %s %s\n", codec->name,
299 					 codec_dai->playback.stream_name);
300 				snd_soc_dapm_set_bias_level(socdev,
301 					SND_SOC_BIAS_STANDBY);
302 			}
303 		}
304 	}
305 	mutex_unlock(&pcm_mutex);
306 }
307 
308 /*
309  * Called by ALSA when a PCM substream is closed. Private data can be
310  * freed here. The cpu DAI, codec DAI, machine and platform are also
311  * shutdown.
312  */
313 static int soc_codec_close(struct snd_pcm_substream *substream)
314 {
315 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
316 	struct snd_soc_device *socdev = rtd->socdev;
317 	struct snd_soc_card *card = socdev->card;
318 	struct snd_soc_dai_link *machine = rtd->dai;
319 	struct snd_soc_platform *platform = card->platform;
320 	struct snd_soc_dai *cpu_dai = machine->cpu_dai;
321 	struct snd_soc_dai *codec_dai = machine->codec_dai;
322 	struct snd_soc_codec *codec = card->codec;
323 
324 	mutex_lock(&pcm_mutex);
325 
326 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
327 		cpu_dai->playback.active = codec_dai->playback.active = 0;
328 	else
329 		cpu_dai->capture.active = codec_dai->capture.active = 0;
330 
331 	if (codec_dai->playback.active == 0 &&
332 		codec_dai->capture.active == 0) {
333 		cpu_dai->active = codec_dai->active = 0;
334 	}
335 	codec->active--;
336 
337 	/* Muting the DAC suppresses artifacts caused during digital
338 	 * shutdown, for example from stopping clocks.
339 	 */
340 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
341 		snd_soc_dai_digital_mute(codec_dai, 1);
342 
343 	if (cpu_dai->ops->shutdown)
344 		cpu_dai->ops->shutdown(substream, cpu_dai);
345 
346 	if (codec_dai->ops->shutdown)
347 		codec_dai->ops->shutdown(substream, codec_dai);
348 
349 	if (machine->ops && machine->ops->shutdown)
350 		machine->ops->shutdown(substream);
351 
352 	if (platform->pcm_ops->close)
353 		platform->pcm_ops->close(substream);
354 	cpu_dai->runtime = NULL;
355 
356 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
357 		/* start delayed pop wq here for playback streams */
358 		codec_dai->pop_wait = 1;
359 		schedule_delayed_work(&card->delayed_work,
360 			msecs_to_jiffies(pmdown_time));
361 	} else {
362 		/* capture streams can be powered down now */
363 		snd_soc_dapm_stream_event(codec,
364 			codec_dai->capture.stream_name,
365 			SND_SOC_DAPM_STREAM_STOP);
366 
367 		if (codec->active == 0 && codec_dai->pop_wait == 0)
368 			snd_soc_dapm_set_bias_level(socdev,
369 						SND_SOC_BIAS_STANDBY);
370 	}
371 
372 	mutex_unlock(&pcm_mutex);
373 	return 0;
374 }
375 
376 /*
377  * Called by ALSA when the PCM substream is prepared, can set format, sample
378  * rate, etc.  This function is non atomic and can be called multiple times,
379  * it can refer to the runtime info.
380  */
381 static int soc_pcm_prepare(struct snd_pcm_substream *substream)
382 {
383 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
384 	struct snd_soc_device *socdev = rtd->socdev;
385 	struct snd_soc_card *card = socdev->card;
386 	struct snd_soc_dai_link *machine = rtd->dai;
387 	struct snd_soc_platform *platform = card->platform;
388 	struct snd_soc_dai *cpu_dai = machine->cpu_dai;
389 	struct snd_soc_dai *codec_dai = machine->codec_dai;
390 	struct snd_soc_codec *codec = card->codec;
391 	int ret = 0;
392 
393 	mutex_lock(&pcm_mutex);
394 
395 	if (machine->ops && machine->ops->prepare) {
396 		ret = machine->ops->prepare(substream);
397 		if (ret < 0) {
398 			printk(KERN_ERR "asoc: machine prepare error\n");
399 			goto out;
400 		}
401 	}
402 
403 	if (platform->pcm_ops->prepare) {
404 		ret = platform->pcm_ops->prepare(substream);
405 		if (ret < 0) {
406 			printk(KERN_ERR "asoc: platform prepare error\n");
407 			goto out;
408 		}
409 	}
410 
411 	if (codec_dai->ops->prepare) {
412 		ret = codec_dai->ops->prepare(substream, codec_dai);
413 		if (ret < 0) {
414 			printk(KERN_ERR "asoc: codec DAI prepare error\n");
415 			goto out;
416 		}
417 	}
418 
419 	if (cpu_dai->ops->prepare) {
420 		ret = cpu_dai->ops->prepare(substream, cpu_dai);
421 		if (ret < 0) {
422 			printk(KERN_ERR "asoc: cpu DAI prepare error\n");
423 			goto out;
424 		}
425 	}
426 
427 	/* cancel any delayed stream shutdown that is pending */
428 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
429 	    codec_dai->pop_wait) {
430 		codec_dai->pop_wait = 0;
431 		cancel_delayed_work(&card->delayed_work);
432 	}
433 
434 	/* do we need to power up codec */
435 	if (codec->bias_level != SND_SOC_BIAS_ON) {
436 		snd_soc_dapm_set_bias_level(socdev,
437 					    SND_SOC_BIAS_PREPARE);
438 
439 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
440 			snd_soc_dapm_stream_event(codec,
441 					codec_dai->playback.stream_name,
442 					SND_SOC_DAPM_STREAM_START);
443 		else
444 			snd_soc_dapm_stream_event(codec,
445 					codec_dai->capture.stream_name,
446 					SND_SOC_DAPM_STREAM_START);
447 
448 		snd_soc_dapm_set_bias_level(socdev, SND_SOC_BIAS_ON);
449 		snd_soc_dai_digital_mute(codec_dai, 0);
450 
451 	} else {
452 		/* codec already powered - power on widgets */
453 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
454 			snd_soc_dapm_stream_event(codec,
455 					codec_dai->playback.stream_name,
456 					SND_SOC_DAPM_STREAM_START);
457 		else
458 			snd_soc_dapm_stream_event(codec,
459 					codec_dai->capture.stream_name,
460 					SND_SOC_DAPM_STREAM_START);
461 
462 		snd_soc_dai_digital_mute(codec_dai, 0);
463 	}
464 
465 out:
466 	mutex_unlock(&pcm_mutex);
467 	return ret;
468 }
469 
470 /*
471  * Called by ALSA when the hardware params are set by application. This
472  * function can also be called multiple times and can allocate buffers
473  * (using snd_pcm_lib_* ). It's non-atomic.
474  */
475 static int soc_pcm_hw_params(struct snd_pcm_substream *substream,
476 				struct snd_pcm_hw_params *params)
477 {
478 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
479 	struct snd_soc_device *socdev = rtd->socdev;
480 	struct snd_soc_dai_link *machine = rtd->dai;
481 	struct snd_soc_card *card = socdev->card;
482 	struct snd_soc_platform *platform = card->platform;
483 	struct snd_soc_dai *cpu_dai = machine->cpu_dai;
484 	struct snd_soc_dai *codec_dai = machine->codec_dai;
485 	int ret = 0;
486 
487 	mutex_lock(&pcm_mutex);
488 
489 	if (machine->ops && machine->ops->hw_params) {
490 		ret = machine->ops->hw_params(substream, params);
491 		if (ret < 0) {
492 			printk(KERN_ERR "asoc: machine hw_params failed\n");
493 			goto out;
494 		}
495 	}
496 
497 	if (codec_dai->ops->hw_params) {
498 		ret = codec_dai->ops->hw_params(substream, params, codec_dai);
499 		if (ret < 0) {
500 			printk(KERN_ERR "asoc: can't set codec %s hw params\n",
501 				codec_dai->name);
502 			goto codec_err;
503 		}
504 	}
505 
506 	if (cpu_dai->ops->hw_params) {
507 		ret = cpu_dai->ops->hw_params(substream, params, cpu_dai);
508 		if (ret < 0) {
509 			printk(KERN_ERR "asoc: interface %s hw params failed\n",
510 				cpu_dai->name);
511 			goto interface_err;
512 		}
513 	}
514 
515 	if (platform->pcm_ops->hw_params) {
516 		ret = platform->pcm_ops->hw_params(substream, params);
517 		if (ret < 0) {
518 			printk(KERN_ERR "asoc: platform %s hw params failed\n",
519 				platform->name);
520 			goto platform_err;
521 		}
522 	}
523 
524 out:
525 	mutex_unlock(&pcm_mutex);
526 	return ret;
527 
528 platform_err:
529 	if (cpu_dai->ops->hw_free)
530 		cpu_dai->ops->hw_free(substream, cpu_dai);
531 
532 interface_err:
533 	if (codec_dai->ops->hw_free)
534 		codec_dai->ops->hw_free(substream, codec_dai);
535 
536 codec_err:
537 	if (machine->ops && machine->ops->hw_free)
538 		machine->ops->hw_free(substream);
539 
540 	mutex_unlock(&pcm_mutex);
541 	return ret;
542 }
543 
544 /*
545  * Free's resources allocated by hw_params, can be called multiple times
546  */
547 static int soc_pcm_hw_free(struct snd_pcm_substream *substream)
548 {
549 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
550 	struct snd_soc_device *socdev = rtd->socdev;
551 	struct snd_soc_dai_link *machine = rtd->dai;
552 	struct snd_soc_card *card = socdev->card;
553 	struct snd_soc_platform *platform = card->platform;
554 	struct snd_soc_dai *cpu_dai = machine->cpu_dai;
555 	struct snd_soc_dai *codec_dai = machine->codec_dai;
556 	struct snd_soc_codec *codec = card->codec;
557 
558 	mutex_lock(&pcm_mutex);
559 
560 	/* apply codec digital mute */
561 	if (!codec->active)
562 		snd_soc_dai_digital_mute(codec_dai, 1);
563 
564 	/* free any machine hw params */
565 	if (machine->ops && machine->ops->hw_free)
566 		machine->ops->hw_free(substream);
567 
568 	/* free any DMA resources */
569 	if (platform->pcm_ops->hw_free)
570 		platform->pcm_ops->hw_free(substream);
571 
572 	/* now free hw params for the DAI's  */
573 	if (codec_dai->ops->hw_free)
574 		codec_dai->ops->hw_free(substream, codec_dai);
575 
576 	if (cpu_dai->ops->hw_free)
577 		cpu_dai->ops->hw_free(substream, cpu_dai);
578 
579 	mutex_unlock(&pcm_mutex);
580 	return 0;
581 }
582 
583 static int soc_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
584 {
585 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
586 	struct snd_soc_device *socdev = rtd->socdev;
587 	struct snd_soc_card *card= socdev->card;
588 	struct snd_soc_dai_link *machine = rtd->dai;
589 	struct snd_soc_platform *platform = card->platform;
590 	struct snd_soc_dai *cpu_dai = machine->cpu_dai;
591 	struct snd_soc_dai *codec_dai = machine->codec_dai;
592 	int ret;
593 
594 	if (codec_dai->ops->trigger) {
595 		ret = codec_dai->ops->trigger(substream, cmd, codec_dai);
596 		if (ret < 0)
597 			return ret;
598 	}
599 
600 	if (platform->pcm_ops->trigger) {
601 		ret = platform->pcm_ops->trigger(substream, cmd);
602 		if (ret < 0)
603 			return ret;
604 	}
605 
606 	if (cpu_dai->ops->trigger) {
607 		ret = cpu_dai->ops->trigger(substream, cmd, cpu_dai);
608 		if (ret < 0)
609 			return ret;
610 	}
611 	return 0;
612 }
613 
614 /* ASoC PCM operations */
615 static struct snd_pcm_ops soc_pcm_ops = {
616 	.open		= soc_pcm_open,
617 	.close		= soc_codec_close,
618 	.hw_params	= soc_pcm_hw_params,
619 	.hw_free	= soc_pcm_hw_free,
620 	.prepare	= soc_pcm_prepare,
621 	.trigger	= soc_pcm_trigger,
622 };
623 
624 #ifdef CONFIG_PM
625 /* powers down audio subsystem for suspend */
626 static int soc_suspend(struct platform_device *pdev, pm_message_t state)
627 {
628 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
629 	struct snd_soc_card *card = socdev->card;
630 	struct snd_soc_platform *platform = card->platform;
631 	struct snd_soc_codec_device *codec_dev = socdev->codec_dev;
632 	struct snd_soc_codec *codec = card->codec;
633 	int i;
634 
635 	/* Due to the resume being scheduled into a workqueue we could
636 	* suspend before that's finished - wait for it to complete.
637 	 */
638 	snd_power_lock(codec->card);
639 	snd_power_wait(codec->card, SNDRV_CTL_POWER_D0);
640 	snd_power_unlock(codec->card);
641 
642 	/* we're going to block userspace touching us until resume completes */
643 	snd_power_change_state(codec->card, SNDRV_CTL_POWER_D3hot);
644 
645 	/* mute any active DAC's */
646 	for (i = 0; i < card->num_links; i++) {
647 		struct snd_soc_dai *dai = card->dai_link[i].codec_dai;
648 		if (dai->ops->digital_mute && dai->playback.active)
649 			dai->ops->digital_mute(dai, 1);
650 	}
651 
652 	/* suspend all pcms */
653 	for (i = 0; i < card->num_links; i++)
654 		snd_pcm_suspend_all(card->dai_link[i].pcm);
655 
656 	if (card->suspend_pre)
657 		card->suspend_pre(pdev, state);
658 
659 	for (i = 0; i < card->num_links; i++) {
660 		struct snd_soc_dai  *cpu_dai = card->dai_link[i].cpu_dai;
661 		if (cpu_dai->suspend && !cpu_dai->ac97_control)
662 			cpu_dai->suspend(cpu_dai);
663 		if (platform->suspend)
664 			platform->suspend(cpu_dai);
665 	}
666 
667 	/* close any waiting streams and save state */
668 	run_delayed_work(&card->delayed_work);
669 	codec->suspend_bias_level = codec->bias_level;
670 
671 	for (i = 0; i < codec->num_dai; i++) {
672 		char *stream = codec->dai[i].playback.stream_name;
673 		if (stream != NULL)
674 			snd_soc_dapm_stream_event(codec, stream,
675 				SND_SOC_DAPM_STREAM_SUSPEND);
676 		stream = codec->dai[i].capture.stream_name;
677 		if (stream != NULL)
678 			snd_soc_dapm_stream_event(codec, stream,
679 				SND_SOC_DAPM_STREAM_SUSPEND);
680 	}
681 
682 	if (codec_dev->suspend)
683 		codec_dev->suspend(pdev, state);
684 
685 	for (i = 0; i < card->num_links; i++) {
686 		struct snd_soc_dai *cpu_dai = card->dai_link[i].cpu_dai;
687 		if (cpu_dai->suspend && cpu_dai->ac97_control)
688 			cpu_dai->suspend(cpu_dai);
689 	}
690 
691 	if (card->suspend_post)
692 		card->suspend_post(pdev, state);
693 
694 	return 0;
695 }
696 
697 /* deferred resume work, so resume can complete before we finished
698  * setting our codec back up, which can be very slow on I2C
699  */
700 static void soc_resume_deferred(struct work_struct *work)
701 {
702 	struct snd_soc_card *card = container_of(work,
703 						 struct snd_soc_card,
704 						 deferred_resume_work);
705 	struct snd_soc_device *socdev = card->socdev;
706 	struct snd_soc_platform *platform = card->platform;
707 	struct snd_soc_codec_device *codec_dev = socdev->codec_dev;
708 	struct snd_soc_codec *codec = card->codec;
709 	struct platform_device *pdev = to_platform_device(socdev->dev);
710 	int i;
711 
712 	/* our power state is still SNDRV_CTL_POWER_D3hot from suspend time,
713 	 * so userspace apps are blocked from touching us
714 	 */
715 
716 	dev_dbg(socdev->dev, "starting resume work\n");
717 
718 	if (card->resume_pre)
719 		card->resume_pre(pdev);
720 
721 	for (i = 0; i < card->num_links; i++) {
722 		struct snd_soc_dai *cpu_dai = card->dai_link[i].cpu_dai;
723 		if (cpu_dai->resume && cpu_dai->ac97_control)
724 			cpu_dai->resume(cpu_dai);
725 	}
726 
727 	if (codec_dev->resume)
728 		codec_dev->resume(pdev);
729 
730 	for (i = 0; i < codec->num_dai; i++) {
731 		char *stream = codec->dai[i].playback.stream_name;
732 		if (stream != NULL)
733 			snd_soc_dapm_stream_event(codec, stream,
734 				SND_SOC_DAPM_STREAM_RESUME);
735 		stream = codec->dai[i].capture.stream_name;
736 		if (stream != NULL)
737 			snd_soc_dapm_stream_event(codec, stream,
738 				SND_SOC_DAPM_STREAM_RESUME);
739 	}
740 
741 	/* unmute any active DACs */
742 	for (i = 0; i < card->num_links; i++) {
743 		struct snd_soc_dai *dai = card->dai_link[i].codec_dai;
744 		if (dai->ops->digital_mute && dai->playback.active)
745 			dai->ops->digital_mute(dai, 0);
746 	}
747 
748 	for (i = 0; i < card->num_links; i++) {
749 		struct snd_soc_dai *cpu_dai = card->dai_link[i].cpu_dai;
750 		if (cpu_dai->resume && !cpu_dai->ac97_control)
751 			cpu_dai->resume(cpu_dai);
752 		if (platform->resume)
753 			platform->resume(cpu_dai);
754 	}
755 
756 	if (card->resume_post)
757 		card->resume_post(pdev);
758 
759 	dev_dbg(socdev->dev, "resume work completed\n");
760 
761 	/* userspace can access us now we are back as we were before */
762 	snd_power_change_state(codec->card, SNDRV_CTL_POWER_D0);
763 }
764 
765 /* powers up audio subsystem after a suspend */
766 static int soc_resume(struct platform_device *pdev)
767 {
768 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
769 	struct snd_soc_card *card = socdev->card;
770 	struct snd_soc_dai *cpu_dai = card->dai_link[0].cpu_dai;
771 
772 	/* AC97 devices might have other drivers hanging off them so
773 	 * need to resume immediately.  Other drivers don't have that
774 	 * problem and may take a substantial amount of time to resume
775 	 * due to I/O costs and anti-pop so handle them out of line.
776 	 */
777 	if (cpu_dai->ac97_control) {
778 		dev_dbg(socdev->dev, "Resuming AC97 immediately\n");
779 		soc_resume_deferred(&card->deferred_resume_work);
780 	} else {
781 		dev_dbg(socdev->dev, "Scheduling resume work\n");
782 		if (!schedule_work(&card->deferred_resume_work))
783 			dev_err(socdev->dev, "resume work item may be lost\n");
784 	}
785 
786 	return 0;
787 }
788 
789 #else
790 #define soc_suspend	NULL
791 #define soc_resume	NULL
792 #endif
793 
794 static void snd_soc_instantiate_card(struct snd_soc_card *card)
795 {
796 	struct platform_device *pdev = container_of(card->dev,
797 						    struct platform_device,
798 						    dev);
799 	struct snd_soc_codec_device *codec_dev = card->socdev->codec_dev;
800 	struct snd_soc_platform *platform;
801 	struct snd_soc_dai *dai;
802 	int i, found, ret, ac97;
803 
804 	if (card->instantiated)
805 		return;
806 
807 	found = 0;
808 	list_for_each_entry(platform, &platform_list, list)
809 		if (card->platform == platform) {
810 			found = 1;
811 			break;
812 		}
813 	if (!found) {
814 		dev_dbg(card->dev, "Platform %s not registered\n",
815 			card->platform->name);
816 		return;
817 	}
818 
819 	ac97 = 0;
820 	for (i = 0; i < card->num_links; i++) {
821 		found = 0;
822 		list_for_each_entry(dai, &dai_list, list)
823 			if (card->dai_link[i].cpu_dai == dai) {
824 				found = 1;
825 				break;
826 			}
827 		if (!found) {
828 			dev_dbg(card->dev, "DAI %s not registered\n",
829 				card->dai_link[i].cpu_dai->name);
830 			return;
831 		}
832 
833 		if (card->dai_link[i].cpu_dai->ac97_control)
834 			ac97 = 1;
835 	}
836 
837 	/* If we have AC97 in the system then don't wait for the
838 	 * codec.  This will need revisiting if we have to handle
839 	 * systems with mixed AC97 and non-AC97 parts.  Only check for
840 	 * DAIs currently; we can't do this per link since some AC97
841 	 * codecs have non-AC97 DAIs.
842 	 */
843 	if (!ac97)
844 		for (i = 0; i < card->num_links; i++) {
845 			found = 0;
846 			list_for_each_entry(dai, &dai_list, list)
847 				if (card->dai_link[i].codec_dai == dai) {
848 					found = 1;
849 					break;
850 				}
851 			if (!found) {
852 				dev_dbg(card->dev, "DAI %s not registered\n",
853 					card->dai_link[i].codec_dai->name);
854 				return;
855 			}
856 		}
857 
858 	/* Note that we do not current check for codec components */
859 
860 	dev_dbg(card->dev, "All components present, instantiating\n");
861 
862 	/* Found everything, bring it up */
863 	if (card->probe) {
864 		ret = card->probe(pdev);
865 		if (ret < 0)
866 			return;
867 	}
868 
869 	for (i = 0; i < card->num_links; i++) {
870 		struct snd_soc_dai *cpu_dai = card->dai_link[i].cpu_dai;
871 		if (cpu_dai->probe) {
872 			ret = cpu_dai->probe(pdev, cpu_dai);
873 			if (ret < 0)
874 				goto cpu_dai_err;
875 		}
876 	}
877 
878 	if (codec_dev->probe) {
879 		ret = codec_dev->probe(pdev);
880 		if (ret < 0)
881 			goto cpu_dai_err;
882 	}
883 
884 	if (platform->probe) {
885 		ret = platform->probe(pdev);
886 		if (ret < 0)
887 			goto platform_err;
888 	}
889 
890 	/* DAPM stream work */
891 	INIT_DELAYED_WORK(&card->delayed_work, close_delayed_work);
892 #ifdef CONFIG_PM
893 	/* deferred resume work */
894 	INIT_WORK(&card->deferred_resume_work, soc_resume_deferred);
895 #endif
896 
897 	card->instantiated = 1;
898 
899 	return;
900 
901 platform_err:
902 	if (codec_dev->remove)
903 		codec_dev->remove(pdev);
904 
905 cpu_dai_err:
906 	for (i--; i >= 0; i--) {
907 		struct snd_soc_dai *cpu_dai = card->dai_link[i].cpu_dai;
908 		if (cpu_dai->remove)
909 			cpu_dai->remove(pdev, cpu_dai);
910 	}
911 
912 	if (card->remove)
913 		card->remove(pdev);
914 }
915 
916 /*
917  * Attempt to initialise any uninitalised cards.  Must be called with
918  * client_mutex.
919  */
920 static void snd_soc_instantiate_cards(void)
921 {
922 	struct snd_soc_card *card;
923 	list_for_each_entry(card, &card_list, list)
924 		snd_soc_instantiate_card(card);
925 }
926 
927 /* probes a new socdev */
928 static int soc_probe(struct platform_device *pdev)
929 {
930 	int ret = 0;
931 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
932 	struct snd_soc_card *card = socdev->card;
933 
934 	/* Bodge while we push things out of socdev */
935 	card->socdev = socdev;
936 
937 	/* Bodge while we unpick instantiation */
938 	card->dev = &pdev->dev;
939 	ret = snd_soc_register_card(card);
940 	if (ret != 0) {
941 		dev_err(&pdev->dev, "Failed to register card\n");
942 		return ret;
943 	}
944 
945 	return 0;
946 }
947 
948 /* removes a socdev */
949 static int soc_remove(struct platform_device *pdev)
950 {
951 	int i;
952 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
953 	struct snd_soc_card *card = socdev->card;
954 	struct snd_soc_platform *platform = card->platform;
955 	struct snd_soc_codec_device *codec_dev = socdev->codec_dev;
956 
957 	run_delayed_work(&card->delayed_work);
958 
959 	if (platform->remove)
960 		platform->remove(pdev);
961 
962 	if (codec_dev->remove)
963 		codec_dev->remove(pdev);
964 
965 	for (i = 0; i < card->num_links; i++) {
966 		struct snd_soc_dai *cpu_dai = card->dai_link[i].cpu_dai;
967 		if (cpu_dai->remove)
968 			cpu_dai->remove(pdev, cpu_dai);
969 	}
970 
971 	if (card->remove)
972 		card->remove(pdev);
973 
974 	snd_soc_unregister_card(card);
975 
976 	return 0;
977 }
978 
979 /* ASoC platform driver */
980 static struct platform_driver soc_driver = {
981 	.driver		= {
982 		.name		= "soc-audio",
983 		.owner		= THIS_MODULE,
984 	},
985 	.probe		= soc_probe,
986 	.remove		= soc_remove,
987 	.suspend	= soc_suspend,
988 	.resume		= soc_resume,
989 };
990 
991 /* create a new pcm */
992 static int soc_new_pcm(struct snd_soc_device *socdev,
993 	struct snd_soc_dai_link *dai_link, int num)
994 {
995 	struct snd_soc_card *card = socdev->card;
996 	struct snd_soc_codec *codec = card->codec;
997 	struct snd_soc_platform *platform = card->platform;
998 	struct snd_soc_dai *codec_dai = dai_link->codec_dai;
999 	struct snd_soc_dai *cpu_dai = dai_link->cpu_dai;
1000 	struct snd_soc_pcm_runtime *rtd;
1001 	struct snd_pcm *pcm;
1002 	char new_name[64];
1003 	int ret = 0, playback = 0, capture = 0;
1004 
1005 	rtd = kzalloc(sizeof(struct snd_soc_pcm_runtime), GFP_KERNEL);
1006 	if (rtd == NULL)
1007 		return -ENOMEM;
1008 
1009 	rtd->dai = dai_link;
1010 	rtd->socdev = socdev;
1011 	codec_dai->codec = card->codec;
1012 
1013 	/* check client and interface hw capabilities */
1014 	sprintf(new_name, "%s %s-%d", dai_link->stream_name, codec_dai->name,
1015 		num);
1016 
1017 	if (codec_dai->playback.channels_min)
1018 		playback = 1;
1019 	if (codec_dai->capture.channels_min)
1020 		capture = 1;
1021 
1022 	ret = snd_pcm_new(codec->card, new_name, codec->pcm_devs++, playback,
1023 		capture, &pcm);
1024 	if (ret < 0) {
1025 		printk(KERN_ERR "asoc: can't create pcm for codec %s\n",
1026 			codec->name);
1027 		kfree(rtd);
1028 		return ret;
1029 	}
1030 
1031 	dai_link->pcm = pcm;
1032 	pcm->private_data = rtd;
1033 	soc_pcm_ops.mmap = platform->pcm_ops->mmap;
1034 	soc_pcm_ops.pointer = platform->pcm_ops->pointer;
1035 	soc_pcm_ops.ioctl = platform->pcm_ops->ioctl;
1036 	soc_pcm_ops.copy = platform->pcm_ops->copy;
1037 	soc_pcm_ops.silence = platform->pcm_ops->silence;
1038 	soc_pcm_ops.ack = platform->pcm_ops->ack;
1039 	soc_pcm_ops.page = platform->pcm_ops->page;
1040 
1041 	if (playback)
1042 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &soc_pcm_ops);
1043 
1044 	if (capture)
1045 		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &soc_pcm_ops);
1046 
1047 	ret = platform->pcm_new(codec->card, codec_dai, pcm);
1048 	if (ret < 0) {
1049 		printk(KERN_ERR "asoc: platform pcm constructor failed\n");
1050 		kfree(rtd);
1051 		return ret;
1052 	}
1053 
1054 	pcm->private_free = platform->pcm_free;
1055 	printk(KERN_INFO "asoc: %s <-> %s mapping ok\n", codec_dai->name,
1056 		cpu_dai->name);
1057 	return ret;
1058 }
1059 
1060 /* codec register dump */
1061 static ssize_t soc_codec_reg_show(struct snd_soc_codec *codec, char *buf)
1062 {
1063 	int i, step = 1, count = 0;
1064 
1065 	if (!codec->reg_cache_size)
1066 		return 0;
1067 
1068 	if (codec->reg_cache_step)
1069 		step = codec->reg_cache_step;
1070 
1071 	count += sprintf(buf, "%s registers\n", codec->name);
1072 	for (i = 0; i < codec->reg_cache_size; i += step) {
1073 		count += sprintf(buf + count, "%2x: ", i);
1074 		if (count >= PAGE_SIZE - 1)
1075 			break;
1076 
1077 		if (codec->display_register)
1078 			count += codec->display_register(codec, buf + count,
1079 							 PAGE_SIZE - count, i);
1080 		else
1081 			count += snprintf(buf + count, PAGE_SIZE - count,
1082 					  "%4x", codec->read(codec, i));
1083 
1084 		if (count >= PAGE_SIZE - 1)
1085 			break;
1086 
1087 		count += snprintf(buf + count, PAGE_SIZE - count, "\n");
1088 		if (count >= PAGE_SIZE - 1)
1089 			break;
1090 	}
1091 
1092 	/* Truncate count; min() would cause a warning */
1093 	if (count >= PAGE_SIZE)
1094 		count = PAGE_SIZE - 1;
1095 
1096 	return count;
1097 }
1098 static ssize_t codec_reg_show(struct device *dev,
1099 	struct device_attribute *attr, char *buf)
1100 {
1101 	struct snd_soc_device *devdata = dev_get_drvdata(dev);
1102 	return soc_codec_reg_show(devdata->card->codec, buf);
1103 }
1104 
1105 static DEVICE_ATTR(codec_reg, 0444, codec_reg_show, NULL);
1106 
1107 #ifdef CONFIG_DEBUG_FS
1108 static int codec_reg_open_file(struct inode *inode, struct file *file)
1109 {
1110 	file->private_data = inode->i_private;
1111 	return 0;
1112 }
1113 
1114 static ssize_t codec_reg_read_file(struct file *file, char __user *user_buf,
1115 			       size_t count, loff_t *ppos)
1116 {
1117 	ssize_t ret;
1118 	struct snd_soc_codec *codec = file->private_data;
1119 	char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1120 	if (!buf)
1121 		return -ENOMEM;
1122 	ret = soc_codec_reg_show(codec, buf);
1123 	if (ret >= 0)
1124 		ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
1125 	kfree(buf);
1126 	return ret;
1127 }
1128 
1129 static ssize_t codec_reg_write_file(struct file *file,
1130 		const char __user *user_buf, size_t count, loff_t *ppos)
1131 {
1132 	char buf[32];
1133 	int buf_size;
1134 	char *start = buf;
1135 	unsigned long reg, value;
1136 	int step = 1;
1137 	struct snd_soc_codec *codec = file->private_data;
1138 
1139 	buf_size = min(count, (sizeof(buf)-1));
1140 	if (copy_from_user(buf, user_buf, buf_size))
1141 		return -EFAULT;
1142 	buf[buf_size] = 0;
1143 
1144 	if (codec->reg_cache_step)
1145 		step = codec->reg_cache_step;
1146 
1147 	while (*start == ' ')
1148 		start++;
1149 	reg = simple_strtoul(start, &start, 16);
1150 	if ((reg >= codec->reg_cache_size) || (reg % step))
1151 		return -EINVAL;
1152 	while (*start == ' ')
1153 		start++;
1154 	if (strict_strtoul(start, 16, &value))
1155 		return -EINVAL;
1156 	codec->write(codec, reg, value);
1157 	return buf_size;
1158 }
1159 
1160 static const struct file_operations codec_reg_fops = {
1161 	.open = codec_reg_open_file,
1162 	.read = codec_reg_read_file,
1163 	.write = codec_reg_write_file,
1164 };
1165 
1166 static void soc_init_codec_debugfs(struct snd_soc_codec *codec)
1167 {
1168 	codec->debugfs_reg = debugfs_create_file("codec_reg", 0644,
1169 						 debugfs_root, codec,
1170 						 &codec_reg_fops);
1171 	if (!codec->debugfs_reg)
1172 		printk(KERN_WARNING
1173 		       "ASoC: Failed to create codec register debugfs file\n");
1174 
1175 	codec->debugfs_pop_time = debugfs_create_u32("dapm_pop_time", 0744,
1176 						     debugfs_root,
1177 						     &codec->pop_time);
1178 	if (!codec->debugfs_pop_time)
1179 		printk(KERN_WARNING
1180 		       "Failed to create pop time debugfs file\n");
1181 }
1182 
1183 static void soc_cleanup_codec_debugfs(struct snd_soc_codec *codec)
1184 {
1185 	debugfs_remove(codec->debugfs_pop_time);
1186 	debugfs_remove(codec->debugfs_reg);
1187 }
1188 
1189 #else
1190 
1191 static inline void soc_init_codec_debugfs(struct snd_soc_codec *codec)
1192 {
1193 }
1194 
1195 static inline void soc_cleanup_codec_debugfs(struct snd_soc_codec *codec)
1196 {
1197 }
1198 #endif
1199 
1200 /**
1201  * snd_soc_new_ac97_codec - initailise AC97 device
1202  * @codec: audio codec
1203  * @ops: AC97 bus operations
1204  * @num: AC97 codec number
1205  *
1206  * Initialises AC97 codec resources for use by ad-hoc devices only.
1207  */
1208 int snd_soc_new_ac97_codec(struct snd_soc_codec *codec,
1209 	struct snd_ac97_bus_ops *ops, int num)
1210 {
1211 	mutex_lock(&codec->mutex);
1212 
1213 	codec->ac97 = kzalloc(sizeof(struct snd_ac97), GFP_KERNEL);
1214 	if (codec->ac97 == NULL) {
1215 		mutex_unlock(&codec->mutex);
1216 		return -ENOMEM;
1217 	}
1218 
1219 	codec->ac97->bus = kzalloc(sizeof(struct snd_ac97_bus), GFP_KERNEL);
1220 	if (codec->ac97->bus == NULL) {
1221 		kfree(codec->ac97);
1222 		codec->ac97 = NULL;
1223 		mutex_unlock(&codec->mutex);
1224 		return -ENOMEM;
1225 	}
1226 
1227 	codec->ac97->bus->ops = ops;
1228 	codec->ac97->num = num;
1229 	mutex_unlock(&codec->mutex);
1230 	return 0;
1231 }
1232 EXPORT_SYMBOL_GPL(snd_soc_new_ac97_codec);
1233 
1234 /**
1235  * snd_soc_free_ac97_codec - free AC97 codec device
1236  * @codec: audio codec
1237  *
1238  * Frees AC97 codec device resources.
1239  */
1240 void snd_soc_free_ac97_codec(struct snd_soc_codec *codec)
1241 {
1242 	mutex_lock(&codec->mutex);
1243 	kfree(codec->ac97->bus);
1244 	kfree(codec->ac97);
1245 	codec->ac97 = NULL;
1246 	mutex_unlock(&codec->mutex);
1247 }
1248 EXPORT_SYMBOL_GPL(snd_soc_free_ac97_codec);
1249 
1250 /**
1251  * snd_soc_update_bits - update codec register bits
1252  * @codec: audio codec
1253  * @reg: codec register
1254  * @mask: register mask
1255  * @value: new value
1256  *
1257  * Writes new register value.
1258  *
1259  * Returns 1 for change else 0.
1260  */
1261 int snd_soc_update_bits(struct snd_soc_codec *codec, unsigned short reg,
1262 				unsigned short mask, unsigned short value)
1263 {
1264 	int change;
1265 	unsigned short old, new;
1266 
1267 	mutex_lock(&io_mutex);
1268 	old = snd_soc_read(codec, reg);
1269 	new = (old & ~mask) | value;
1270 	change = old != new;
1271 	if (change)
1272 		snd_soc_write(codec, reg, new);
1273 
1274 	mutex_unlock(&io_mutex);
1275 	return change;
1276 }
1277 EXPORT_SYMBOL_GPL(snd_soc_update_bits);
1278 
1279 /**
1280  * snd_soc_test_bits - test register for change
1281  * @codec: audio codec
1282  * @reg: codec register
1283  * @mask: register mask
1284  * @value: new value
1285  *
1286  * Tests a register with a new value and checks if the new value is
1287  * different from the old value.
1288  *
1289  * Returns 1 for change else 0.
1290  */
1291 int snd_soc_test_bits(struct snd_soc_codec *codec, unsigned short reg,
1292 				unsigned short mask, unsigned short value)
1293 {
1294 	int change;
1295 	unsigned short old, new;
1296 
1297 	mutex_lock(&io_mutex);
1298 	old = snd_soc_read(codec, reg);
1299 	new = (old & ~mask) | value;
1300 	change = old != new;
1301 	mutex_unlock(&io_mutex);
1302 
1303 	return change;
1304 }
1305 EXPORT_SYMBOL_GPL(snd_soc_test_bits);
1306 
1307 /**
1308  * snd_soc_new_pcms - create new sound card and pcms
1309  * @socdev: the SoC audio device
1310  * @idx: ALSA card index
1311  * @xid: card identification
1312  *
1313  * Create a new sound card based upon the codec and interface pcms.
1314  *
1315  * Returns 0 for success, else error.
1316  */
1317 int snd_soc_new_pcms(struct snd_soc_device *socdev, int idx, const char *xid)
1318 {
1319 	struct snd_soc_card *card = socdev->card;
1320 	struct snd_soc_codec *codec = card->codec;
1321 	int ret, i;
1322 
1323 	mutex_lock(&codec->mutex);
1324 
1325 	/* register a sound card */
1326 	ret = snd_card_create(idx, xid, codec->owner, 0, &codec->card);
1327 	if (ret < 0) {
1328 		printk(KERN_ERR "asoc: can't create sound card for codec %s\n",
1329 			codec->name);
1330 		mutex_unlock(&codec->mutex);
1331 		return ret;
1332 	}
1333 
1334 	codec->card->dev = socdev->dev;
1335 	codec->card->private_data = codec;
1336 	strncpy(codec->card->driver, codec->name, sizeof(codec->card->driver));
1337 
1338 	/* create the pcms */
1339 	for (i = 0; i < card->num_links; i++) {
1340 		ret = soc_new_pcm(socdev, &card->dai_link[i], i);
1341 		if (ret < 0) {
1342 			printk(KERN_ERR "asoc: can't create pcm %s\n",
1343 				card->dai_link[i].stream_name);
1344 			mutex_unlock(&codec->mutex);
1345 			return ret;
1346 		}
1347 	}
1348 
1349 	mutex_unlock(&codec->mutex);
1350 	return ret;
1351 }
1352 EXPORT_SYMBOL_GPL(snd_soc_new_pcms);
1353 
1354 /**
1355  * snd_soc_init_card - register sound card
1356  * @socdev: the SoC audio device
1357  *
1358  * Register a SoC sound card. Also registers an AC97 device if the
1359  * codec is AC97 for ad hoc devices.
1360  *
1361  * Returns 0 for success, else error.
1362  */
1363 int snd_soc_init_card(struct snd_soc_device *socdev)
1364 {
1365 	struct snd_soc_card *card = socdev->card;
1366 	struct snd_soc_codec *codec = card->codec;
1367 	int ret = 0, i, ac97 = 0, err = 0;
1368 
1369 	for (i = 0; i < card->num_links; i++) {
1370 		if (card->dai_link[i].init) {
1371 			err = card->dai_link[i].init(codec);
1372 			if (err < 0) {
1373 				printk(KERN_ERR "asoc: failed to init %s\n",
1374 					card->dai_link[i].stream_name);
1375 				continue;
1376 			}
1377 		}
1378 		if (card->dai_link[i].codec_dai->ac97_control)
1379 			ac97 = 1;
1380 	}
1381 	snprintf(codec->card->shortname, sizeof(codec->card->shortname),
1382 		 "%s",  card->name);
1383 	snprintf(codec->card->longname, sizeof(codec->card->longname),
1384 		 "%s (%s)", card->name, codec->name);
1385 
1386 	ret = snd_card_register(codec->card);
1387 	if (ret < 0) {
1388 		printk(KERN_ERR "asoc: failed to register soundcard for %s\n",
1389 				codec->name);
1390 		goto out;
1391 	}
1392 
1393 	mutex_lock(&codec->mutex);
1394 #ifdef CONFIG_SND_SOC_AC97_BUS
1395 	/* Only instantiate AC97 if not already done by the adaptor
1396 	 * for the generic AC97 subsystem.
1397 	 */
1398 	if (ac97 && strcmp(codec->name, "AC97") != 0) {
1399 		ret = soc_ac97_dev_register(codec);
1400 		if (ret < 0) {
1401 			printk(KERN_ERR "asoc: AC97 device register failed\n");
1402 			snd_card_free(codec->card);
1403 			mutex_unlock(&codec->mutex);
1404 			goto out;
1405 		}
1406 	}
1407 #endif
1408 
1409 	err = snd_soc_dapm_sys_add(socdev->dev);
1410 	if (err < 0)
1411 		printk(KERN_WARNING "asoc: failed to add dapm sysfs entries\n");
1412 
1413 	err = device_create_file(socdev->dev, &dev_attr_codec_reg);
1414 	if (err < 0)
1415 		printk(KERN_WARNING "asoc: failed to add codec sysfs files\n");
1416 
1417 	soc_init_codec_debugfs(codec);
1418 	mutex_unlock(&codec->mutex);
1419 
1420 out:
1421 	return ret;
1422 }
1423 EXPORT_SYMBOL_GPL(snd_soc_init_card);
1424 
1425 /**
1426  * snd_soc_free_pcms - free sound card and pcms
1427  * @socdev: the SoC audio device
1428  *
1429  * Frees sound card and pcms associated with the socdev.
1430  * Also unregister the codec if it is an AC97 device.
1431  */
1432 void snd_soc_free_pcms(struct snd_soc_device *socdev)
1433 {
1434 	struct snd_soc_codec *codec = socdev->card->codec;
1435 #ifdef CONFIG_SND_SOC_AC97_BUS
1436 	struct snd_soc_dai *codec_dai;
1437 	int i;
1438 #endif
1439 
1440 	mutex_lock(&codec->mutex);
1441 	soc_cleanup_codec_debugfs(codec);
1442 #ifdef CONFIG_SND_SOC_AC97_BUS
1443 	for (i = 0; i < codec->num_dai; i++) {
1444 		codec_dai = &codec->dai[i];
1445 		if (codec_dai->ac97_control && codec->ac97 &&
1446 		    strcmp(codec->name, "AC97") != 0) {
1447 			soc_ac97_dev_unregister(codec);
1448 			goto free_card;
1449 		}
1450 	}
1451 free_card:
1452 #endif
1453 
1454 	if (codec->card)
1455 		snd_card_free(codec->card);
1456 	device_remove_file(socdev->dev, &dev_attr_codec_reg);
1457 	mutex_unlock(&codec->mutex);
1458 }
1459 EXPORT_SYMBOL_GPL(snd_soc_free_pcms);
1460 
1461 /**
1462  * snd_soc_set_runtime_hwparams - set the runtime hardware parameters
1463  * @substream: the pcm substream
1464  * @hw: the hardware parameters
1465  *
1466  * Sets the substream runtime hardware parameters.
1467  */
1468 int snd_soc_set_runtime_hwparams(struct snd_pcm_substream *substream,
1469 	const struct snd_pcm_hardware *hw)
1470 {
1471 	struct snd_pcm_runtime *runtime = substream->runtime;
1472 	runtime->hw.info = hw->info;
1473 	runtime->hw.formats = hw->formats;
1474 	runtime->hw.period_bytes_min = hw->period_bytes_min;
1475 	runtime->hw.period_bytes_max = hw->period_bytes_max;
1476 	runtime->hw.periods_min = hw->periods_min;
1477 	runtime->hw.periods_max = hw->periods_max;
1478 	runtime->hw.buffer_bytes_max = hw->buffer_bytes_max;
1479 	runtime->hw.fifo_size = hw->fifo_size;
1480 	return 0;
1481 }
1482 EXPORT_SYMBOL_GPL(snd_soc_set_runtime_hwparams);
1483 
1484 /**
1485  * snd_soc_cnew - create new control
1486  * @_template: control template
1487  * @data: control private data
1488  * @long_name: control long name
1489  *
1490  * Create a new mixer control from a template control.
1491  *
1492  * Returns 0 for success, else error.
1493  */
1494 struct snd_kcontrol *snd_soc_cnew(const struct snd_kcontrol_new *_template,
1495 	void *data, char *long_name)
1496 {
1497 	struct snd_kcontrol_new template;
1498 
1499 	memcpy(&template, _template, sizeof(template));
1500 	if (long_name)
1501 		template.name = long_name;
1502 	template.index = 0;
1503 
1504 	return snd_ctl_new1(&template, data);
1505 }
1506 EXPORT_SYMBOL_GPL(snd_soc_cnew);
1507 
1508 /**
1509  * snd_soc_add_controls - add an array of controls to a codec.
1510  * Convienience function to add a list of controls. Many codecs were
1511  * duplicating this code.
1512  *
1513  * @codec: codec to add controls to
1514  * @controls: array of controls to add
1515  * @num_controls: number of elements in the array
1516  *
1517  * Return 0 for success, else error.
1518  */
1519 int snd_soc_add_controls(struct snd_soc_codec *codec,
1520 	const struct snd_kcontrol_new *controls, int num_controls)
1521 {
1522 	struct snd_card *card = codec->card;
1523 	int err, i;
1524 
1525 	for (i = 0; i < num_controls; i++) {
1526 		const struct snd_kcontrol_new *control = &controls[i];
1527 		err = snd_ctl_add(card, snd_soc_cnew(control, codec, NULL));
1528 		if (err < 0) {
1529 			dev_err(codec->dev, "%s: Failed to add %s\n",
1530 				codec->name, control->name);
1531 			return err;
1532 		}
1533 	}
1534 
1535 	return 0;
1536 }
1537 EXPORT_SYMBOL_GPL(snd_soc_add_controls);
1538 
1539 /**
1540  * snd_soc_info_enum_double - enumerated double mixer info callback
1541  * @kcontrol: mixer control
1542  * @uinfo: control element information
1543  *
1544  * Callback to provide information about a double enumerated
1545  * mixer control.
1546  *
1547  * Returns 0 for success.
1548  */
1549 int snd_soc_info_enum_double(struct snd_kcontrol *kcontrol,
1550 	struct snd_ctl_elem_info *uinfo)
1551 {
1552 	struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
1553 
1554 	uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
1555 	uinfo->count = e->shift_l == e->shift_r ? 1 : 2;
1556 	uinfo->value.enumerated.items = e->max;
1557 
1558 	if (uinfo->value.enumerated.item > e->max - 1)
1559 		uinfo->value.enumerated.item = e->max - 1;
1560 	strcpy(uinfo->value.enumerated.name,
1561 		e->texts[uinfo->value.enumerated.item]);
1562 	return 0;
1563 }
1564 EXPORT_SYMBOL_GPL(snd_soc_info_enum_double);
1565 
1566 /**
1567  * snd_soc_get_enum_double - enumerated double mixer get callback
1568  * @kcontrol: mixer control
1569  * @ucontrol: control element information
1570  *
1571  * Callback to get the value of a double enumerated mixer.
1572  *
1573  * Returns 0 for success.
1574  */
1575 int snd_soc_get_enum_double(struct snd_kcontrol *kcontrol,
1576 	struct snd_ctl_elem_value *ucontrol)
1577 {
1578 	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
1579 	struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
1580 	unsigned short val, bitmask;
1581 
1582 	for (bitmask = 1; bitmask < e->max; bitmask <<= 1)
1583 		;
1584 	val = snd_soc_read(codec, e->reg);
1585 	ucontrol->value.enumerated.item[0]
1586 		= (val >> e->shift_l) & (bitmask - 1);
1587 	if (e->shift_l != e->shift_r)
1588 		ucontrol->value.enumerated.item[1] =
1589 			(val >> e->shift_r) & (bitmask - 1);
1590 
1591 	return 0;
1592 }
1593 EXPORT_SYMBOL_GPL(snd_soc_get_enum_double);
1594 
1595 /**
1596  * snd_soc_put_enum_double - enumerated double mixer put callback
1597  * @kcontrol: mixer control
1598  * @ucontrol: control element information
1599  *
1600  * Callback to set the value of a double enumerated mixer.
1601  *
1602  * Returns 0 for success.
1603  */
1604 int snd_soc_put_enum_double(struct snd_kcontrol *kcontrol,
1605 	struct snd_ctl_elem_value *ucontrol)
1606 {
1607 	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
1608 	struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
1609 	unsigned short val;
1610 	unsigned short mask, bitmask;
1611 
1612 	for (bitmask = 1; bitmask < e->max; bitmask <<= 1)
1613 		;
1614 	if (ucontrol->value.enumerated.item[0] > e->max - 1)
1615 		return -EINVAL;
1616 	val = ucontrol->value.enumerated.item[0] << e->shift_l;
1617 	mask = (bitmask - 1) << e->shift_l;
1618 	if (e->shift_l != e->shift_r) {
1619 		if (ucontrol->value.enumerated.item[1] > e->max - 1)
1620 			return -EINVAL;
1621 		val |= ucontrol->value.enumerated.item[1] << e->shift_r;
1622 		mask |= (bitmask - 1) << e->shift_r;
1623 	}
1624 
1625 	return snd_soc_update_bits(codec, e->reg, mask, val);
1626 }
1627 EXPORT_SYMBOL_GPL(snd_soc_put_enum_double);
1628 
1629 /**
1630  * snd_soc_get_value_enum_double - semi enumerated double mixer get callback
1631  * @kcontrol: mixer control
1632  * @ucontrol: control element information
1633  *
1634  * Callback to get the value of a double semi enumerated mixer.
1635  *
1636  * Semi enumerated mixer: the enumerated items are referred as values. Can be
1637  * used for handling bitfield coded enumeration for example.
1638  *
1639  * Returns 0 for success.
1640  */
1641 int snd_soc_get_value_enum_double(struct snd_kcontrol *kcontrol,
1642 	struct snd_ctl_elem_value *ucontrol)
1643 {
1644 	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
1645 	struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
1646 	unsigned short reg_val, val, mux;
1647 
1648 	reg_val = snd_soc_read(codec, e->reg);
1649 	val = (reg_val >> e->shift_l) & e->mask;
1650 	for (mux = 0; mux < e->max; mux++) {
1651 		if (val == e->values[mux])
1652 			break;
1653 	}
1654 	ucontrol->value.enumerated.item[0] = mux;
1655 	if (e->shift_l != e->shift_r) {
1656 		val = (reg_val >> e->shift_r) & e->mask;
1657 		for (mux = 0; mux < e->max; mux++) {
1658 			if (val == e->values[mux])
1659 				break;
1660 		}
1661 		ucontrol->value.enumerated.item[1] = mux;
1662 	}
1663 
1664 	return 0;
1665 }
1666 EXPORT_SYMBOL_GPL(snd_soc_get_value_enum_double);
1667 
1668 /**
1669  * snd_soc_put_value_enum_double - semi enumerated double mixer put callback
1670  * @kcontrol: mixer control
1671  * @ucontrol: control element information
1672  *
1673  * Callback to set the value of a double semi enumerated mixer.
1674  *
1675  * Semi enumerated mixer: the enumerated items are referred as values. Can be
1676  * used for handling bitfield coded enumeration for example.
1677  *
1678  * Returns 0 for success.
1679  */
1680 int snd_soc_put_value_enum_double(struct snd_kcontrol *kcontrol,
1681 	struct snd_ctl_elem_value *ucontrol)
1682 {
1683 	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
1684 	struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
1685 	unsigned short val;
1686 	unsigned short mask;
1687 
1688 	if (ucontrol->value.enumerated.item[0] > e->max - 1)
1689 		return -EINVAL;
1690 	val = e->values[ucontrol->value.enumerated.item[0]] << e->shift_l;
1691 	mask = e->mask << e->shift_l;
1692 	if (e->shift_l != e->shift_r) {
1693 		if (ucontrol->value.enumerated.item[1] > e->max - 1)
1694 			return -EINVAL;
1695 		val |= e->values[ucontrol->value.enumerated.item[1]] << e->shift_r;
1696 		mask |= e->mask << e->shift_r;
1697 	}
1698 
1699 	return snd_soc_update_bits(codec, e->reg, mask, val);
1700 }
1701 EXPORT_SYMBOL_GPL(snd_soc_put_value_enum_double);
1702 
1703 /**
1704  * snd_soc_info_enum_ext - external enumerated single mixer info callback
1705  * @kcontrol: mixer control
1706  * @uinfo: control element information
1707  *
1708  * Callback to provide information about an external enumerated
1709  * single mixer.
1710  *
1711  * Returns 0 for success.
1712  */
1713 int snd_soc_info_enum_ext(struct snd_kcontrol *kcontrol,
1714 	struct snd_ctl_elem_info *uinfo)
1715 {
1716 	struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
1717 
1718 	uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
1719 	uinfo->count = 1;
1720 	uinfo->value.enumerated.items = e->max;
1721 
1722 	if (uinfo->value.enumerated.item > e->max - 1)
1723 		uinfo->value.enumerated.item = e->max - 1;
1724 	strcpy(uinfo->value.enumerated.name,
1725 		e->texts[uinfo->value.enumerated.item]);
1726 	return 0;
1727 }
1728 EXPORT_SYMBOL_GPL(snd_soc_info_enum_ext);
1729 
1730 /**
1731  * snd_soc_info_volsw_ext - external single mixer info callback
1732  * @kcontrol: mixer control
1733  * @uinfo: control element information
1734  *
1735  * Callback to provide information about a single external mixer control.
1736  *
1737  * Returns 0 for success.
1738  */
1739 int snd_soc_info_volsw_ext(struct snd_kcontrol *kcontrol,
1740 	struct snd_ctl_elem_info *uinfo)
1741 {
1742 	int max = kcontrol->private_value;
1743 
1744 	if (max == 1)
1745 		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1746 	else
1747 		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1748 
1749 	uinfo->count = 1;
1750 	uinfo->value.integer.min = 0;
1751 	uinfo->value.integer.max = max;
1752 	return 0;
1753 }
1754 EXPORT_SYMBOL_GPL(snd_soc_info_volsw_ext);
1755 
1756 /**
1757  * snd_soc_info_volsw - single mixer info callback
1758  * @kcontrol: mixer control
1759  * @uinfo: control element information
1760  *
1761  * Callback to provide information about a single mixer control.
1762  *
1763  * Returns 0 for success.
1764  */
1765 int snd_soc_info_volsw(struct snd_kcontrol *kcontrol,
1766 	struct snd_ctl_elem_info *uinfo)
1767 {
1768 	struct soc_mixer_control *mc =
1769 		(struct soc_mixer_control *)kcontrol->private_value;
1770 	int max = mc->max;
1771 	unsigned int shift = mc->shift;
1772 	unsigned int rshift = mc->rshift;
1773 
1774 	if (max == 1)
1775 		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1776 	else
1777 		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1778 
1779 	uinfo->count = shift == rshift ? 1 : 2;
1780 	uinfo->value.integer.min = 0;
1781 	uinfo->value.integer.max = max;
1782 	return 0;
1783 }
1784 EXPORT_SYMBOL_GPL(snd_soc_info_volsw);
1785 
1786 /**
1787  * snd_soc_get_volsw - single mixer get callback
1788  * @kcontrol: mixer control
1789  * @ucontrol: control element information
1790  *
1791  * Callback to get the value of a single mixer control.
1792  *
1793  * Returns 0 for success.
1794  */
1795 int snd_soc_get_volsw(struct snd_kcontrol *kcontrol,
1796 	struct snd_ctl_elem_value *ucontrol)
1797 {
1798 	struct soc_mixer_control *mc =
1799 		(struct soc_mixer_control *)kcontrol->private_value;
1800 	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
1801 	unsigned int reg = mc->reg;
1802 	unsigned int shift = mc->shift;
1803 	unsigned int rshift = mc->rshift;
1804 	int max = mc->max;
1805 	unsigned int mask = (1 << fls(max)) - 1;
1806 	unsigned int invert = mc->invert;
1807 
1808 	ucontrol->value.integer.value[0] =
1809 		(snd_soc_read(codec, reg) >> shift) & mask;
1810 	if (shift != rshift)
1811 		ucontrol->value.integer.value[1] =
1812 			(snd_soc_read(codec, reg) >> rshift) & mask;
1813 	if (invert) {
1814 		ucontrol->value.integer.value[0] =
1815 			max - ucontrol->value.integer.value[0];
1816 		if (shift != rshift)
1817 			ucontrol->value.integer.value[1] =
1818 				max - ucontrol->value.integer.value[1];
1819 	}
1820 
1821 	return 0;
1822 }
1823 EXPORT_SYMBOL_GPL(snd_soc_get_volsw);
1824 
1825 /**
1826  * snd_soc_put_volsw - single mixer put callback
1827  * @kcontrol: mixer control
1828  * @ucontrol: control element information
1829  *
1830  * Callback to set the value of a single mixer control.
1831  *
1832  * Returns 0 for success.
1833  */
1834 int snd_soc_put_volsw(struct snd_kcontrol *kcontrol,
1835 	struct snd_ctl_elem_value *ucontrol)
1836 {
1837 	struct soc_mixer_control *mc =
1838 		(struct soc_mixer_control *)kcontrol->private_value;
1839 	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
1840 	unsigned int reg = mc->reg;
1841 	unsigned int shift = mc->shift;
1842 	unsigned int rshift = mc->rshift;
1843 	int max = mc->max;
1844 	unsigned int mask = (1 << fls(max)) - 1;
1845 	unsigned int invert = mc->invert;
1846 	unsigned short val, val2, val_mask;
1847 
1848 	val = (ucontrol->value.integer.value[0] & mask);
1849 	if (invert)
1850 		val = max - val;
1851 	val_mask = mask << shift;
1852 	val = val << shift;
1853 	if (shift != rshift) {
1854 		val2 = (ucontrol->value.integer.value[1] & mask);
1855 		if (invert)
1856 			val2 = max - val2;
1857 		val_mask |= mask << rshift;
1858 		val |= val2 << rshift;
1859 	}
1860 	return snd_soc_update_bits(codec, reg, val_mask, val);
1861 }
1862 EXPORT_SYMBOL_GPL(snd_soc_put_volsw);
1863 
1864 /**
1865  * snd_soc_info_volsw_2r - double mixer info callback
1866  * @kcontrol: mixer control
1867  * @uinfo: control element information
1868  *
1869  * Callback to provide information about a double mixer control that
1870  * spans 2 codec registers.
1871  *
1872  * Returns 0 for success.
1873  */
1874 int snd_soc_info_volsw_2r(struct snd_kcontrol *kcontrol,
1875 	struct snd_ctl_elem_info *uinfo)
1876 {
1877 	struct soc_mixer_control *mc =
1878 		(struct soc_mixer_control *)kcontrol->private_value;
1879 	int max = mc->max;
1880 
1881 	if (max == 1)
1882 		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1883 	else
1884 		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1885 
1886 	uinfo->count = 2;
1887 	uinfo->value.integer.min = 0;
1888 	uinfo->value.integer.max = max;
1889 	return 0;
1890 }
1891 EXPORT_SYMBOL_GPL(snd_soc_info_volsw_2r);
1892 
1893 /**
1894  * snd_soc_get_volsw_2r - double mixer get callback
1895  * @kcontrol: mixer control
1896  * @ucontrol: control element information
1897  *
1898  * Callback to get the value of a double mixer control that spans 2 registers.
1899  *
1900  * Returns 0 for success.
1901  */
1902 int snd_soc_get_volsw_2r(struct snd_kcontrol *kcontrol,
1903 	struct snd_ctl_elem_value *ucontrol)
1904 {
1905 	struct soc_mixer_control *mc =
1906 		(struct soc_mixer_control *)kcontrol->private_value;
1907 	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
1908 	unsigned int reg = mc->reg;
1909 	unsigned int reg2 = mc->rreg;
1910 	unsigned int shift = mc->shift;
1911 	int max = mc->max;
1912 	unsigned int mask = (1<<fls(max))-1;
1913 	unsigned int invert = mc->invert;
1914 
1915 	ucontrol->value.integer.value[0] =
1916 		(snd_soc_read(codec, reg) >> shift) & mask;
1917 	ucontrol->value.integer.value[1] =
1918 		(snd_soc_read(codec, reg2) >> shift) & mask;
1919 	if (invert) {
1920 		ucontrol->value.integer.value[0] =
1921 			max - ucontrol->value.integer.value[0];
1922 		ucontrol->value.integer.value[1] =
1923 			max - ucontrol->value.integer.value[1];
1924 	}
1925 
1926 	return 0;
1927 }
1928 EXPORT_SYMBOL_GPL(snd_soc_get_volsw_2r);
1929 
1930 /**
1931  * snd_soc_put_volsw_2r - double mixer set callback
1932  * @kcontrol: mixer control
1933  * @ucontrol: control element information
1934  *
1935  * Callback to set the value of a double mixer control that spans 2 registers.
1936  *
1937  * Returns 0 for success.
1938  */
1939 int snd_soc_put_volsw_2r(struct snd_kcontrol *kcontrol,
1940 	struct snd_ctl_elem_value *ucontrol)
1941 {
1942 	struct soc_mixer_control *mc =
1943 		(struct soc_mixer_control *)kcontrol->private_value;
1944 	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
1945 	unsigned int reg = mc->reg;
1946 	unsigned int reg2 = mc->rreg;
1947 	unsigned int shift = mc->shift;
1948 	int max = mc->max;
1949 	unsigned int mask = (1 << fls(max)) - 1;
1950 	unsigned int invert = mc->invert;
1951 	int err;
1952 	unsigned short val, val2, val_mask;
1953 
1954 	val_mask = mask << shift;
1955 	val = (ucontrol->value.integer.value[0] & mask);
1956 	val2 = (ucontrol->value.integer.value[1] & mask);
1957 
1958 	if (invert) {
1959 		val = max - val;
1960 		val2 = max - val2;
1961 	}
1962 
1963 	val = val << shift;
1964 	val2 = val2 << shift;
1965 
1966 	err = snd_soc_update_bits(codec, reg, val_mask, val);
1967 	if (err < 0)
1968 		return err;
1969 
1970 	err = snd_soc_update_bits(codec, reg2, val_mask, val2);
1971 	return err;
1972 }
1973 EXPORT_SYMBOL_GPL(snd_soc_put_volsw_2r);
1974 
1975 /**
1976  * snd_soc_info_volsw_s8 - signed mixer info callback
1977  * @kcontrol: mixer control
1978  * @uinfo: control element information
1979  *
1980  * Callback to provide information about a signed mixer control.
1981  *
1982  * Returns 0 for success.
1983  */
1984 int snd_soc_info_volsw_s8(struct snd_kcontrol *kcontrol,
1985 	struct snd_ctl_elem_info *uinfo)
1986 {
1987 	struct soc_mixer_control *mc =
1988 		(struct soc_mixer_control *)kcontrol->private_value;
1989 	int max = mc->max;
1990 	int min = mc->min;
1991 
1992 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1993 	uinfo->count = 2;
1994 	uinfo->value.integer.min = 0;
1995 	uinfo->value.integer.max = max-min;
1996 	return 0;
1997 }
1998 EXPORT_SYMBOL_GPL(snd_soc_info_volsw_s8);
1999 
2000 /**
2001  * snd_soc_get_volsw_s8 - signed mixer get callback
2002  * @kcontrol: mixer control
2003  * @ucontrol: control element information
2004  *
2005  * Callback to get the value of a signed mixer control.
2006  *
2007  * Returns 0 for success.
2008  */
2009 int snd_soc_get_volsw_s8(struct snd_kcontrol *kcontrol,
2010 	struct snd_ctl_elem_value *ucontrol)
2011 {
2012 	struct soc_mixer_control *mc =
2013 		(struct soc_mixer_control *)kcontrol->private_value;
2014 	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
2015 	unsigned int reg = mc->reg;
2016 	int min = mc->min;
2017 	int val = snd_soc_read(codec, reg);
2018 
2019 	ucontrol->value.integer.value[0] =
2020 		((signed char)(val & 0xff))-min;
2021 	ucontrol->value.integer.value[1] =
2022 		((signed char)((val >> 8) & 0xff))-min;
2023 	return 0;
2024 }
2025 EXPORT_SYMBOL_GPL(snd_soc_get_volsw_s8);
2026 
2027 /**
2028  * snd_soc_put_volsw_sgn - signed mixer put callback
2029  * @kcontrol: mixer control
2030  * @ucontrol: control element information
2031  *
2032  * Callback to set the value of a signed mixer control.
2033  *
2034  * Returns 0 for success.
2035  */
2036 int snd_soc_put_volsw_s8(struct snd_kcontrol *kcontrol,
2037 	struct snd_ctl_elem_value *ucontrol)
2038 {
2039 	struct soc_mixer_control *mc =
2040 		(struct soc_mixer_control *)kcontrol->private_value;
2041 	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
2042 	unsigned int reg = mc->reg;
2043 	int min = mc->min;
2044 	unsigned short val;
2045 
2046 	val = (ucontrol->value.integer.value[0]+min) & 0xff;
2047 	val |= ((ucontrol->value.integer.value[1]+min) & 0xff) << 8;
2048 
2049 	return snd_soc_update_bits(codec, reg, 0xffff, val);
2050 }
2051 EXPORT_SYMBOL_GPL(snd_soc_put_volsw_s8);
2052 
2053 /**
2054  * snd_soc_dai_set_sysclk - configure DAI system or master clock.
2055  * @dai: DAI
2056  * @clk_id: DAI specific clock ID
2057  * @freq: new clock frequency in Hz
2058  * @dir: new clock direction - input/output.
2059  *
2060  * Configures the DAI master (MCLK) or system (SYSCLK) clocking.
2061  */
2062 int snd_soc_dai_set_sysclk(struct snd_soc_dai *dai, int clk_id,
2063 	unsigned int freq, int dir)
2064 {
2065 	if (dai->ops->set_sysclk)
2066 		return dai->ops->set_sysclk(dai, clk_id, freq, dir);
2067 	else
2068 		return -EINVAL;
2069 }
2070 EXPORT_SYMBOL_GPL(snd_soc_dai_set_sysclk);
2071 
2072 /**
2073  * snd_soc_dai_set_clkdiv - configure DAI clock dividers.
2074  * @dai: DAI
2075  * @div_id: DAI specific clock divider ID
2076  * @div: new clock divisor.
2077  *
2078  * Configures the clock dividers. This is used to derive the best DAI bit and
2079  * frame clocks from the system or master clock. It's best to set the DAI bit
2080  * and frame clocks as low as possible to save system power.
2081  */
2082 int snd_soc_dai_set_clkdiv(struct snd_soc_dai *dai,
2083 	int div_id, int div)
2084 {
2085 	if (dai->ops->set_clkdiv)
2086 		return dai->ops->set_clkdiv(dai, div_id, div);
2087 	else
2088 		return -EINVAL;
2089 }
2090 EXPORT_SYMBOL_GPL(snd_soc_dai_set_clkdiv);
2091 
2092 /**
2093  * snd_soc_dai_set_pll - configure DAI PLL.
2094  * @dai: DAI
2095  * @pll_id: DAI specific PLL ID
2096  * @freq_in: PLL input clock frequency in Hz
2097  * @freq_out: requested PLL output clock frequency in Hz
2098  *
2099  * Configures and enables PLL to generate output clock based on input clock.
2100  */
2101 int snd_soc_dai_set_pll(struct snd_soc_dai *dai,
2102 	int pll_id, unsigned int freq_in, unsigned int freq_out)
2103 {
2104 	if (dai->ops->set_pll)
2105 		return dai->ops->set_pll(dai, pll_id, freq_in, freq_out);
2106 	else
2107 		return -EINVAL;
2108 }
2109 EXPORT_SYMBOL_GPL(snd_soc_dai_set_pll);
2110 
2111 /**
2112  * snd_soc_dai_set_fmt - configure DAI hardware audio format.
2113  * @dai: DAI
2114  * @fmt: SND_SOC_DAIFMT_ format value.
2115  *
2116  * Configures the DAI hardware format and clocking.
2117  */
2118 int snd_soc_dai_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
2119 {
2120 	if (dai->ops->set_fmt)
2121 		return dai->ops->set_fmt(dai, fmt);
2122 	else
2123 		return -EINVAL;
2124 }
2125 EXPORT_SYMBOL_GPL(snd_soc_dai_set_fmt);
2126 
2127 /**
2128  * snd_soc_dai_set_tdm_slot - configure DAI TDM.
2129  * @dai: DAI
2130  * @mask: DAI specific mask representing used slots.
2131  * @slots: Number of slots in use.
2132  *
2133  * Configures a DAI for TDM operation. Both mask and slots are codec and DAI
2134  * specific.
2135  */
2136 int snd_soc_dai_set_tdm_slot(struct snd_soc_dai *dai,
2137 	unsigned int mask, int slots)
2138 {
2139 	if (dai->ops->set_sysclk)
2140 		return dai->ops->set_tdm_slot(dai, mask, slots);
2141 	else
2142 		return -EINVAL;
2143 }
2144 EXPORT_SYMBOL_GPL(snd_soc_dai_set_tdm_slot);
2145 
2146 /**
2147  * snd_soc_dai_set_tristate - configure DAI system or master clock.
2148  * @dai: DAI
2149  * @tristate: tristate enable
2150  *
2151  * Tristates the DAI so that others can use it.
2152  */
2153 int snd_soc_dai_set_tristate(struct snd_soc_dai *dai, int tristate)
2154 {
2155 	if (dai->ops->set_sysclk)
2156 		return dai->ops->set_tristate(dai, tristate);
2157 	else
2158 		return -EINVAL;
2159 }
2160 EXPORT_SYMBOL_GPL(snd_soc_dai_set_tristate);
2161 
2162 /**
2163  * snd_soc_dai_digital_mute - configure DAI system or master clock.
2164  * @dai: DAI
2165  * @mute: mute enable
2166  *
2167  * Mutes the DAI DAC.
2168  */
2169 int snd_soc_dai_digital_mute(struct snd_soc_dai *dai, int mute)
2170 {
2171 	if (dai->ops->digital_mute)
2172 		return dai->ops->digital_mute(dai, mute);
2173 	else
2174 		return -EINVAL;
2175 }
2176 EXPORT_SYMBOL_GPL(snd_soc_dai_digital_mute);
2177 
2178 /**
2179  * snd_soc_register_card - Register a card with the ASoC core
2180  *
2181  * @card: Card to register
2182  *
2183  * Note that currently this is an internal only function: it will be
2184  * exposed to machine drivers after further backporting of ASoC v2
2185  * registration APIs.
2186  */
2187 static int snd_soc_register_card(struct snd_soc_card *card)
2188 {
2189 	if (!card->name || !card->dev)
2190 		return -EINVAL;
2191 
2192 	INIT_LIST_HEAD(&card->list);
2193 	card->instantiated = 0;
2194 
2195 	mutex_lock(&client_mutex);
2196 	list_add(&card->list, &card_list);
2197 	snd_soc_instantiate_cards();
2198 	mutex_unlock(&client_mutex);
2199 
2200 	dev_dbg(card->dev, "Registered card '%s'\n", card->name);
2201 
2202 	return 0;
2203 }
2204 
2205 /**
2206  * snd_soc_unregister_card - Unregister a card with the ASoC core
2207  *
2208  * @card: Card to unregister
2209  *
2210  * Note that currently this is an internal only function: it will be
2211  * exposed to machine drivers after further backporting of ASoC v2
2212  * registration APIs.
2213  */
2214 static int snd_soc_unregister_card(struct snd_soc_card *card)
2215 {
2216 	mutex_lock(&client_mutex);
2217 	list_del(&card->list);
2218 	mutex_unlock(&client_mutex);
2219 
2220 	dev_dbg(card->dev, "Unregistered card '%s'\n", card->name);
2221 
2222 	return 0;
2223 }
2224 
2225 static struct snd_soc_dai_ops null_dai_ops = {
2226 };
2227 
2228 /**
2229  * snd_soc_register_dai - Register a DAI with the ASoC core
2230  *
2231  * @dai: DAI to register
2232  */
2233 int snd_soc_register_dai(struct snd_soc_dai *dai)
2234 {
2235 	if (!dai->name)
2236 		return -EINVAL;
2237 
2238 	/* The device should become mandatory over time */
2239 	if (!dai->dev)
2240 		printk(KERN_WARNING "No device for DAI %s\n", dai->name);
2241 
2242 	if (!dai->ops)
2243 		dai->ops = &null_dai_ops;
2244 
2245 	INIT_LIST_HEAD(&dai->list);
2246 
2247 	mutex_lock(&client_mutex);
2248 	list_add(&dai->list, &dai_list);
2249 	snd_soc_instantiate_cards();
2250 	mutex_unlock(&client_mutex);
2251 
2252 	pr_debug("Registered DAI '%s'\n", dai->name);
2253 
2254 	return 0;
2255 }
2256 EXPORT_SYMBOL_GPL(snd_soc_register_dai);
2257 
2258 /**
2259  * snd_soc_unregister_dai - Unregister a DAI from the ASoC core
2260  *
2261  * @dai: DAI to unregister
2262  */
2263 void snd_soc_unregister_dai(struct snd_soc_dai *dai)
2264 {
2265 	mutex_lock(&client_mutex);
2266 	list_del(&dai->list);
2267 	mutex_unlock(&client_mutex);
2268 
2269 	pr_debug("Unregistered DAI '%s'\n", dai->name);
2270 }
2271 EXPORT_SYMBOL_GPL(snd_soc_unregister_dai);
2272 
2273 /**
2274  * snd_soc_register_dais - Register multiple DAIs with the ASoC core
2275  *
2276  * @dai: Array of DAIs to register
2277  * @count: Number of DAIs
2278  */
2279 int snd_soc_register_dais(struct snd_soc_dai *dai, size_t count)
2280 {
2281 	int i, ret;
2282 
2283 	for (i = 0; i < count; i++) {
2284 		ret = snd_soc_register_dai(&dai[i]);
2285 		if (ret != 0)
2286 			goto err;
2287 	}
2288 
2289 	return 0;
2290 
2291 err:
2292 	for (i--; i >= 0; i--)
2293 		snd_soc_unregister_dai(&dai[i]);
2294 
2295 	return ret;
2296 }
2297 EXPORT_SYMBOL_GPL(snd_soc_register_dais);
2298 
2299 /**
2300  * snd_soc_unregister_dais - Unregister multiple DAIs from the ASoC core
2301  *
2302  * @dai: Array of DAIs to unregister
2303  * @count: Number of DAIs
2304  */
2305 void snd_soc_unregister_dais(struct snd_soc_dai *dai, size_t count)
2306 {
2307 	int i;
2308 
2309 	for (i = 0; i < count; i++)
2310 		snd_soc_unregister_dai(&dai[i]);
2311 }
2312 EXPORT_SYMBOL_GPL(snd_soc_unregister_dais);
2313 
2314 /**
2315  * snd_soc_register_platform - Register a platform with the ASoC core
2316  *
2317  * @platform: platform to register
2318  */
2319 int snd_soc_register_platform(struct snd_soc_platform *platform)
2320 {
2321 	if (!platform->name)
2322 		return -EINVAL;
2323 
2324 	INIT_LIST_HEAD(&platform->list);
2325 
2326 	mutex_lock(&client_mutex);
2327 	list_add(&platform->list, &platform_list);
2328 	snd_soc_instantiate_cards();
2329 	mutex_unlock(&client_mutex);
2330 
2331 	pr_debug("Registered platform '%s'\n", platform->name);
2332 
2333 	return 0;
2334 }
2335 EXPORT_SYMBOL_GPL(snd_soc_register_platform);
2336 
2337 /**
2338  * snd_soc_unregister_platform - Unregister a platform from the ASoC core
2339  *
2340  * @platform: platform to unregister
2341  */
2342 void snd_soc_unregister_platform(struct snd_soc_platform *platform)
2343 {
2344 	mutex_lock(&client_mutex);
2345 	list_del(&platform->list);
2346 	mutex_unlock(&client_mutex);
2347 
2348 	pr_debug("Unregistered platform '%s'\n", platform->name);
2349 }
2350 EXPORT_SYMBOL_GPL(snd_soc_unregister_platform);
2351 
2352 /**
2353  * snd_soc_register_codec - Register a codec with the ASoC core
2354  *
2355  * @codec: codec to register
2356  */
2357 int snd_soc_register_codec(struct snd_soc_codec *codec)
2358 {
2359 	if (!codec->name)
2360 		return -EINVAL;
2361 
2362 	/* The device should become mandatory over time */
2363 	if (!codec->dev)
2364 		printk(KERN_WARNING "No device for codec %s\n", codec->name);
2365 
2366 	INIT_LIST_HEAD(&codec->list);
2367 
2368 	mutex_lock(&client_mutex);
2369 	list_add(&codec->list, &codec_list);
2370 	snd_soc_instantiate_cards();
2371 	mutex_unlock(&client_mutex);
2372 
2373 	pr_debug("Registered codec '%s'\n", codec->name);
2374 
2375 	return 0;
2376 }
2377 EXPORT_SYMBOL_GPL(snd_soc_register_codec);
2378 
2379 /**
2380  * snd_soc_unregister_codec - Unregister a codec from the ASoC core
2381  *
2382  * @codec: codec to unregister
2383  */
2384 void snd_soc_unregister_codec(struct snd_soc_codec *codec)
2385 {
2386 	mutex_lock(&client_mutex);
2387 	list_del(&codec->list);
2388 	mutex_unlock(&client_mutex);
2389 
2390 	pr_debug("Unregistered codec '%s'\n", codec->name);
2391 }
2392 EXPORT_SYMBOL_GPL(snd_soc_unregister_codec);
2393 
2394 static int __init snd_soc_init(void)
2395 {
2396 #ifdef CONFIG_DEBUG_FS
2397 	debugfs_root = debugfs_create_dir("asoc", NULL);
2398 	if (IS_ERR(debugfs_root) || !debugfs_root) {
2399 		printk(KERN_WARNING
2400 		       "ASoC: Failed to create debugfs directory\n");
2401 		debugfs_root = NULL;
2402 	}
2403 #endif
2404 
2405 	return platform_driver_register(&soc_driver);
2406 }
2407 
2408 static void __exit snd_soc_exit(void)
2409 {
2410 #ifdef CONFIG_DEBUG_FS
2411 	debugfs_remove_recursive(debugfs_root);
2412 #endif
2413 	platform_driver_unregister(&soc_driver);
2414 }
2415 
2416 module_init(snd_soc_init);
2417 module_exit(snd_soc_exit);
2418 
2419 /* Module information */
2420 MODULE_AUTHOR("Liam Girdwood, lrg@slimlogic.co.uk");
2421 MODULE_DESCRIPTION("ALSA SoC Core");
2422 MODULE_LICENSE("GPL");
2423 MODULE_ALIAS("platform:soc-audio");
2424