xref: /openbmc/linux/sound/soc/codecs/wm8731.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
1 /*
2  * wm8731.c  --  WM8731 ALSA SoC Audio driver
3  *
4  * Copyright 2005 Openedhand Ltd.
5  *
6  * Author: Richard Purdie <richard@openedhand.com>
7  *
8  * Based on wm8753.c by Liam Girdwood
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 
15 #include <linux/module.h>
16 #include <linux/moduleparam.h>
17 #include <linux/init.h>
18 #include <linux/delay.h>
19 #include <linux/pm.h>
20 #include <linux/i2c.h>
21 #include <linux/platform_device.h>
22 #include <linux/spi/spi.h>
23 #include <sound/core.h>
24 #include <sound/pcm.h>
25 #include <sound/pcm_params.h>
26 #include <sound/soc.h>
27 #include <sound/soc-dapm.h>
28 #include <sound/initval.h>
29 
30 #include "wm8731.h"
31 
32 static struct snd_soc_codec *wm8731_codec;
33 struct snd_soc_codec_device soc_codec_dev_wm8731;
34 
35 /* codec private data */
36 struct wm8731_priv {
37 	struct snd_soc_codec codec;
38 	u16 reg_cache[WM8731_CACHEREGNUM];
39 	unsigned int sysclk;
40 };
41 
42 #ifdef CONFIG_SPI_MASTER
43 static int wm8731_spi_write(struct spi_device *spi, const char *data, int len);
44 #endif
45 
46 /*
47  * wm8731 register cache
48  * We can't read the WM8731 register space when we are
49  * using 2 wire for device control, so we cache them instead.
50  * There is no point in caching the reset register
51  */
52 static const u16 wm8731_reg[WM8731_CACHEREGNUM] = {
53     0x0097, 0x0097, 0x0079, 0x0079,
54     0x000a, 0x0008, 0x009f, 0x000a,
55     0x0000, 0x0000
56 };
57 
58 /*
59  * read wm8731 register cache
60  */
61 static inline unsigned int wm8731_read_reg_cache(struct snd_soc_codec *codec,
62 	unsigned int reg)
63 {
64 	u16 *cache = codec->reg_cache;
65 	if (reg == WM8731_RESET)
66 		return 0;
67 	if (reg >= WM8731_CACHEREGNUM)
68 		return -1;
69 	return cache[reg];
70 }
71 
72 /*
73  * write wm8731 register cache
74  */
75 static inline void wm8731_write_reg_cache(struct snd_soc_codec *codec,
76 	u16 reg, unsigned int value)
77 {
78 	u16 *cache = codec->reg_cache;
79 	if (reg >= WM8731_CACHEREGNUM)
80 		return;
81 	cache[reg] = value;
82 }
83 
84 /*
85  * write to the WM8731 register space
86  */
87 static int wm8731_write(struct snd_soc_codec *codec, unsigned int reg,
88 	unsigned int value)
89 {
90 	u8 data[2];
91 
92 	/* data is
93 	 *   D15..D9 WM8731 register offset
94 	 *   D8...D0 register data
95 	 */
96 	data[0] = (reg << 1) | ((value >> 8) & 0x0001);
97 	data[1] = value & 0x00ff;
98 
99 	wm8731_write_reg_cache(codec, reg, value);
100 	if (codec->hw_write(codec->control_data, data, 2) == 2)
101 		return 0;
102 	else
103 		return -EIO;
104 }
105 
106 #define wm8731_reset(c)	wm8731_write(c, WM8731_RESET, 0)
107 
108 static const char *wm8731_input_select[] = {"Line In", "Mic"};
109 static const char *wm8731_deemph[] = {"None", "32Khz", "44.1Khz", "48Khz"};
110 
111 static const struct soc_enum wm8731_enum[] = {
112 	SOC_ENUM_SINGLE(WM8731_APANA, 2, 2, wm8731_input_select),
113 	SOC_ENUM_SINGLE(WM8731_APDIGI, 1, 4, wm8731_deemph),
114 };
115 
116 static const struct snd_kcontrol_new wm8731_snd_controls[] = {
117 
118 SOC_DOUBLE_R("Master Playback Volume", WM8731_LOUT1V, WM8731_ROUT1V,
119 	0, 127, 0),
120 SOC_DOUBLE_R("Master Playback ZC Switch", WM8731_LOUT1V, WM8731_ROUT1V,
121 	7, 1, 0),
122 
123 SOC_DOUBLE_R("Capture Volume", WM8731_LINVOL, WM8731_RINVOL, 0, 31, 0),
124 SOC_DOUBLE_R("Line Capture Switch", WM8731_LINVOL, WM8731_RINVOL, 7, 1, 1),
125 
126 SOC_SINGLE("Mic Boost (+20dB)", WM8731_APANA, 0, 1, 0),
127 SOC_SINGLE("Capture Mic Switch", WM8731_APANA, 1, 1, 1),
128 
129 SOC_SINGLE("Sidetone Playback Volume", WM8731_APANA, 6, 3, 1),
130 
131 SOC_SINGLE("ADC High Pass Filter Switch", WM8731_APDIGI, 0, 1, 1),
132 SOC_SINGLE("Store DC Offset Switch", WM8731_APDIGI, 4, 1, 0),
133 
134 SOC_ENUM("Playback De-emphasis", wm8731_enum[1]),
135 };
136 
137 /* Output Mixer */
138 static const struct snd_kcontrol_new wm8731_output_mixer_controls[] = {
139 SOC_DAPM_SINGLE("Line Bypass Switch", WM8731_APANA, 3, 1, 0),
140 SOC_DAPM_SINGLE("Mic Sidetone Switch", WM8731_APANA, 5, 1, 0),
141 SOC_DAPM_SINGLE("HiFi Playback Switch", WM8731_APANA, 4, 1, 0),
142 };
143 
144 /* Input mux */
145 static const struct snd_kcontrol_new wm8731_input_mux_controls =
146 SOC_DAPM_ENUM("Input Select", wm8731_enum[0]);
147 
148 static const struct snd_soc_dapm_widget wm8731_dapm_widgets[] = {
149 SND_SOC_DAPM_MIXER("Output Mixer", WM8731_PWR, 4, 1,
150 	&wm8731_output_mixer_controls[0],
151 	ARRAY_SIZE(wm8731_output_mixer_controls)),
152 SND_SOC_DAPM_DAC("DAC", "HiFi Playback", WM8731_PWR, 3, 1),
153 SND_SOC_DAPM_OUTPUT("LOUT"),
154 SND_SOC_DAPM_OUTPUT("LHPOUT"),
155 SND_SOC_DAPM_OUTPUT("ROUT"),
156 SND_SOC_DAPM_OUTPUT("RHPOUT"),
157 SND_SOC_DAPM_ADC("ADC", "HiFi Capture", WM8731_PWR, 2, 1),
158 SND_SOC_DAPM_MUX("Input Mux", SND_SOC_NOPM, 0, 0, &wm8731_input_mux_controls),
159 SND_SOC_DAPM_PGA("Line Input", WM8731_PWR, 0, 1, NULL, 0),
160 SND_SOC_DAPM_MICBIAS("Mic Bias", WM8731_PWR, 1, 1),
161 SND_SOC_DAPM_INPUT("MICIN"),
162 SND_SOC_DAPM_INPUT("RLINEIN"),
163 SND_SOC_DAPM_INPUT("LLINEIN"),
164 };
165 
166 static const struct snd_soc_dapm_route intercon[] = {
167 	/* output mixer */
168 	{"Output Mixer", "Line Bypass Switch", "Line Input"},
169 	{"Output Mixer", "HiFi Playback Switch", "DAC"},
170 	{"Output Mixer", "Mic Sidetone Switch", "Mic Bias"},
171 
172 	/* outputs */
173 	{"RHPOUT", NULL, "Output Mixer"},
174 	{"ROUT", NULL, "Output Mixer"},
175 	{"LHPOUT", NULL, "Output Mixer"},
176 	{"LOUT", NULL, "Output Mixer"},
177 
178 	/* input mux */
179 	{"Input Mux", "Line In", "Line Input"},
180 	{"Input Mux", "Mic", "Mic Bias"},
181 	{"ADC", NULL, "Input Mux"},
182 
183 	/* inputs */
184 	{"Line Input", NULL, "LLINEIN"},
185 	{"Line Input", NULL, "RLINEIN"},
186 	{"Mic Bias", NULL, "MICIN"},
187 };
188 
189 static int wm8731_add_widgets(struct snd_soc_codec *codec)
190 {
191 	snd_soc_dapm_new_controls(codec, wm8731_dapm_widgets,
192 				  ARRAY_SIZE(wm8731_dapm_widgets));
193 
194 	snd_soc_dapm_add_routes(codec, intercon, ARRAY_SIZE(intercon));
195 
196 	snd_soc_dapm_new_widgets(codec);
197 	return 0;
198 }
199 
200 struct _coeff_div {
201 	u32 mclk;
202 	u32 rate;
203 	u16 fs;
204 	u8 sr:4;
205 	u8 bosr:1;
206 	u8 usb:1;
207 };
208 
209 /* codec mclk clock divider coefficients */
210 static const struct _coeff_div coeff_div[] = {
211 	/* 48k */
212 	{12288000, 48000, 256, 0x0, 0x0, 0x0},
213 	{18432000, 48000, 384, 0x0, 0x1, 0x0},
214 	{12000000, 48000, 250, 0x0, 0x0, 0x1},
215 
216 	/* 32k */
217 	{12288000, 32000, 384, 0x6, 0x0, 0x0},
218 	{18432000, 32000, 576, 0x6, 0x1, 0x0},
219 	{12000000, 32000, 375, 0x6, 0x0, 0x1},
220 
221 	/* 8k */
222 	{12288000, 8000, 1536, 0x3, 0x0, 0x0},
223 	{18432000, 8000, 2304, 0x3, 0x1, 0x0},
224 	{11289600, 8000, 1408, 0xb, 0x0, 0x0},
225 	{16934400, 8000, 2112, 0xb, 0x1, 0x0},
226 	{12000000, 8000, 1500, 0x3, 0x0, 0x1},
227 
228 	/* 96k */
229 	{12288000, 96000, 128, 0x7, 0x0, 0x0},
230 	{18432000, 96000, 192, 0x7, 0x1, 0x0},
231 	{12000000, 96000, 125, 0x7, 0x0, 0x1},
232 
233 	/* 44.1k */
234 	{11289600, 44100, 256, 0x8, 0x0, 0x0},
235 	{16934400, 44100, 384, 0x8, 0x1, 0x0},
236 	{12000000, 44100, 272, 0x8, 0x1, 0x1},
237 
238 	/* 88.2k */
239 	{11289600, 88200, 128, 0xf, 0x0, 0x0},
240 	{16934400, 88200, 192, 0xf, 0x1, 0x0},
241 	{12000000, 88200, 136, 0xf, 0x1, 0x1},
242 };
243 
244 static inline int get_coeff(int mclk, int rate)
245 {
246 	int i;
247 
248 	for (i = 0; i < ARRAY_SIZE(coeff_div); i++) {
249 		if (coeff_div[i].rate == rate && coeff_div[i].mclk == mclk)
250 			return i;
251 	}
252 	return 0;
253 }
254 
255 static int wm8731_hw_params(struct snd_pcm_substream *substream,
256 			    struct snd_pcm_hw_params *params,
257 			    struct snd_soc_dai *dai)
258 {
259 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
260 	struct snd_soc_device *socdev = rtd->socdev;
261 	struct snd_soc_codec *codec = socdev->card->codec;
262 	struct wm8731_priv *wm8731 = codec->private_data;
263 	u16 iface = wm8731_read_reg_cache(codec, WM8731_IFACE) & 0xfff3;
264 	int i = get_coeff(wm8731->sysclk, params_rate(params));
265 	u16 srate = (coeff_div[i].sr << 2) |
266 		(coeff_div[i].bosr << 1) | coeff_div[i].usb;
267 
268 	wm8731_write(codec, WM8731_SRATE, srate);
269 
270 	/* bit size */
271 	switch (params_format(params)) {
272 	case SNDRV_PCM_FORMAT_S16_LE:
273 		break;
274 	case SNDRV_PCM_FORMAT_S20_3LE:
275 		iface |= 0x0004;
276 		break;
277 	case SNDRV_PCM_FORMAT_S24_LE:
278 		iface |= 0x0008;
279 		break;
280 	}
281 
282 	wm8731_write(codec, WM8731_IFACE, iface);
283 	return 0;
284 }
285 
286 static int wm8731_pcm_prepare(struct snd_pcm_substream *substream,
287 			      struct snd_soc_dai *dai)
288 {
289 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
290 	struct snd_soc_device *socdev = rtd->socdev;
291 	struct snd_soc_codec *codec = socdev->card->codec;
292 
293 	/* set active */
294 	wm8731_write(codec, WM8731_ACTIVE, 0x0001);
295 
296 	return 0;
297 }
298 
299 static void wm8731_shutdown(struct snd_pcm_substream *substream,
300 			    struct snd_soc_dai *dai)
301 {
302 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
303 	struct snd_soc_device *socdev = rtd->socdev;
304 	struct snd_soc_codec *codec = socdev->card->codec;
305 
306 	/* deactivate */
307 	if (!codec->active) {
308 		udelay(50);
309 		wm8731_write(codec, WM8731_ACTIVE, 0x0);
310 	}
311 }
312 
313 static int wm8731_mute(struct snd_soc_dai *dai, int mute)
314 {
315 	struct snd_soc_codec *codec = dai->codec;
316 	u16 mute_reg = wm8731_read_reg_cache(codec, WM8731_APDIGI) & 0xfff7;
317 
318 	if (mute)
319 		wm8731_write(codec, WM8731_APDIGI, mute_reg | 0x8);
320 	else
321 		wm8731_write(codec, WM8731_APDIGI, mute_reg);
322 	return 0;
323 }
324 
325 static int wm8731_set_dai_sysclk(struct snd_soc_dai *codec_dai,
326 		int clk_id, unsigned int freq, int dir)
327 {
328 	struct snd_soc_codec *codec = codec_dai->codec;
329 	struct wm8731_priv *wm8731 = codec->private_data;
330 
331 	switch (freq) {
332 	case 11289600:
333 	case 12000000:
334 	case 12288000:
335 	case 16934400:
336 	case 18432000:
337 		wm8731->sysclk = freq;
338 		return 0;
339 	}
340 	return -EINVAL;
341 }
342 
343 
344 static int wm8731_set_dai_fmt(struct snd_soc_dai *codec_dai,
345 		unsigned int fmt)
346 {
347 	struct snd_soc_codec *codec = codec_dai->codec;
348 	u16 iface = 0;
349 
350 	/* set master/slave audio interface */
351 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
352 	case SND_SOC_DAIFMT_CBM_CFM:
353 		iface |= 0x0040;
354 		break;
355 	case SND_SOC_DAIFMT_CBS_CFS:
356 		break;
357 	default:
358 		return -EINVAL;
359 	}
360 
361 	/* interface format */
362 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
363 	case SND_SOC_DAIFMT_I2S:
364 		iface |= 0x0002;
365 		break;
366 	case SND_SOC_DAIFMT_RIGHT_J:
367 		break;
368 	case SND_SOC_DAIFMT_LEFT_J:
369 		iface |= 0x0001;
370 		break;
371 	case SND_SOC_DAIFMT_DSP_A:
372 		iface |= 0x0003;
373 		break;
374 	case SND_SOC_DAIFMT_DSP_B:
375 		iface |= 0x0013;
376 		break;
377 	default:
378 		return -EINVAL;
379 	}
380 
381 	/* clock inversion */
382 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
383 	case SND_SOC_DAIFMT_NB_NF:
384 		break;
385 	case SND_SOC_DAIFMT_IB_IF:
386 		iface |= 0x0090;
387 		break;
388 	case SND_SOC_DAIFMT_IB_NF:
389 		iface |= 0x0080;
390 		break;
391 	case SND_SOC_DAIFMT_NB_IF:
392 		iface |= 0x0010;
393 		break;
394 	default:
395 		return -EINVAL;
396 	}
397 
398 	/* set iface */
399 	wm8731_write(codec, WM8731_IFACE, iface);
400 	return 0;
401 }
402 
403 static int wm8731_set_bias_level(struct snd_soc_codec *codec,
404 				 enum snd_soc_bias_level level)
405 {
406 	u16 reg;
407 
408 	switch (level) {
409 	case SND_SOC_BIAS_ON:
410 		break;
411 	case SND_SOC_BIAS_PREPARE:
412 		break;
413 	case SND_SOC_BIAS_STANDBY:
414 		/* Clear PWROFF, gate CLKOUT, everything else as-is */
415 		reg = wm8731_read_reg_cache(codec, WM8731_PWR) & 0xff7f;
416 		wm8731_write(codec, WM8731_PWR, reg | 0x0040);
417 		break;
418 	case SND_SOC_BIAS_OFF:
419 		wm8731_write(codec, WM8731_ACTIVE, 0x0);
420 		wm8731_write(codec, WM8731_PWR, 0xffff);
421 		break;
422 	}
423 	codec->bias_level = level;
424 	return 0;
425 }
426 
427 #define WM8731_RATES (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 |\
428 		SNDRV_PCM_RATE_16000 | SNDRV_PCM_RATE_22050 |\
429 		SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 |\
430 		SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_88200 |\
431 		SNDRV_PCM_RATE_96000)
432 
433 #define WM8731_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE |\
434 	SNDRV_PCM_FMTBIT_S24_LE)
435 
436 static struct snd_soc_dai_ops wm8731_dai_ops = {
437 	.prepare	= wm8731_pcm_prepare,
438 	.hw_params	= wm8731_hw_params,
439 	.shutdown	= wm8731_shutdown,
440 	.digital_mute	= wm8731_mute,
441 	.set_sysclk	= wm8731_set_dai_sysclk,
442 	.set_fmt	= wm8731_set_dai_fmt,
443 };
444 
445 struct snd_soc_dai wm8731_dai = {
446 	.name = "WM8731",
447 	.playback = {
448 		.stream_name = "Playback",
449 		.channels_min = 1,
450 		.channels_max = 2,
451 		.rates = WM8731_RATES,
452 		.formats = WM8731_FORMATS,},
453 	.capture = {
454 		.stream_name = "Capture",
455 		.channels_min = 1,
456 		.channels_max = 2,
457 		.rates = WM8731_RATES,
458 		.formats = WM8731_FORMATS,},
459 	.ops = &wm8731_dai_ops,
460 };
461 EXPORT_SYMBOL_GPL(wm8731_dai);
462 
463 static int wm8731_suspend(struct platform_device *pdev, pm_message_t state)
464 {
465 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
466 	struct snd_soc_codec *codec = socdev->card->codec;
467 
468 	wm8731_write(codec, WM8731_ACTIVE, 0x0);
469 	wm8731_set_bias_level(codec, SND_SOC_BIAS_OFF);
470 	return 0;
471 }
472 
473 static int wm8731_resume(struct platform_device *pdev)
474 {
475 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
476 	struct snd_soc_codec *codec = socdev->card->codec;
477 	int i;
478 	u8 data[2];
479 	u16 *cache = codec->reg_cache;
480 
481 	/* Sync reg_cache with the hardware */
482 	for (i = 0; i < ARRAY_SIZE(wm8731_reg); i++) {
483 		data[0] = (i << 1) | ((cache[i] >> 8) & 0x0001);
484 		data[1] = cache[i] & 0x00ff;
485 		codec->hw_write(codec->control_data, data, 2);
486 	}
487 	wm8731_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
488 	wm8731_set_bias_level(codec, codec->suspend_bias_level);
489 	return 0;
490 }
491 
492 static int wm8731_probe(struct platform_device *pdev)
493 {
494 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
495 	struct snd_soc_codec *codec;
496 	int ret = 0;
497 
498 	if (wm8731_codec == NULL) {
499 		dev_err(&pdev->dev, "Codec device not registered\n");
500 		return -ENODEV;
501 	}
502 
503 	socdev->card->codec = wm8731_codec;
504 	codec = wm8731_codec;
505 
506 	/* register pcms */
507 	ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
508 	if (ret < 0) {
509 		dev_err(codec->dev, "failed to create pcms: %d\n", ret);
510 		goto pcm_err;
511 	}
512 
513 	snd_soc_add_controls(codec, wm8731_snd_controls,
514 			     ARRAY_SIZE(wm8731_snd_controls));
515 	wm8731_add_widgets(codec);
516 	ret = snd_soc_init_card(socdev);
517 	if (ret < 0) {
518 		dev_err(codec->dev, "failed to register card: %d\n", ret);
519 		goto card_err;
520 	}
521 
522 	return ret;
523 
524 card_err:
525 	snd_soc_free_pcms(socdev);
526 	snd_soc_dapm_free(socdev);
527 pcm_err:
528 	return ret;
529 }
530 
531 /* power down chip */
532 static int wm8731_remove(struct platform_device *pdev)
533 {
534 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
535 
536 	snd_soc_free_pcms(socdev);
537 	snd_soc_dapm_free(socdev);
538 
539 	return 0;
540 }
541 
542 struct snd_soc_codec_device soc_codec_dev_wm8731 = {
543 	.probe = 	wm8731_probe,
544 	.remove = 	wm8731_remove,
545 	.suspend = 	wm8731_suspend,
546 	.resume =	wm8731_resume,
547 };
548 EXPORT_SYMBOL_GPL(soc_codec_dev_wm8731);
549 
550 static int wm8731_register(struct wm8731_priv *wm8731)
551 {
552 	int ret;
553 	struct snd_soc_codec *codec = &wm8731->codec;
554 	u16 reg;
555 
556 	if (wm8731_codec) {
557 		dev_err(codec->dev, "Another WM8731 is registered\n");
558 		return -EINVAL;
559 	}
560 
561 	mutex_init(&codec->mutex);
562 	INIT_LIST_HEAD(&codec->dapm_widgets);
563 	INIT_LIST_HEAD(&codec->dapm_paths);
564 
565 	codec->private_data = wm8731;
566 	codec->name = "WM8731";
567 	codec->owner = THIS_MODULE;
568 	codec->read = wm8731_read_reg_cache;
569 	codec->write = wm8731_write;
570 	codec->bias_level = SND_SOC_BIAS_OFF;
571 	codec->set_bias_level = wm8731_set_bias_level;
572 	codec->dai = &wm8731_dai;
573 	codec->num_dai = 1;
574 	codec->reg_cache_size = WM8731_CACHEREGNUM;
575 	codec->reg_cache = &wm8731->reg_cache;
576 
577 	memcpy(codec->reg_cache, wm8731_reg, sizeof(wm8731_reg));
578 
579 	ret = wm8731_reset(codec);
580 	if (ret < 0) {
581 		dev_err(codec->dev, "Failed to issue reset\n");
582 		return ret;
583 	}
584 
585 	wm8731_dai.dev = codec->dev;
586 
587 	wm8731_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
588 
589 	/* Latch the update bits */
590 	reg = wm8731_read_reg_cache(codec, WM8731_LOUT1V);
591 	wm8731_write(codec, WM8731_LOUT1V, reg & ~0x0100);
592 	reg = wm8731_read_reg_cache(codec, WM8731_ROUT1V);
593 	wm8731_write(codec, WM8731_ROUT1V, reg & ~0x0100);
594 	reg = wm8731_read_reg_cache(codec, WM8731_LINVOL);
595 	wm8731_write(codec, WM8731_LINVOL, reg & ~0x0100);
596 	reg = wm8731_read_reg_cache(codec, WM8731_RINVOL);
597 	wm8731_write(codec, WM8731_RINVOL, reg & ~0x0100);
598 
599 	/* Disable bypass path by default */
600 	reg = wm8731_read_reg_cache(codec, WM8731_APANA);
601 	wm8731_write(codec, WM8731_APANA, reg & ~0x4);
602 
603 	wm8731_codec = codec;
604 
605 	ret = snd_soc_register_codec(codec);
606 	if (ret != 0) {
607 		dev_err(codec->dev, "Failed to register codec: %d\n", ret);
608 		return ret;
609 	}
610 
611 	ret = snd_soc_register_dai(&wm8731_dai);
612 	if (ret != 0) {
613 		dev_err(codec->dev, "Failed to register DAI: %d\n", ret);
614 		snd_soc_unregister_codec(codec);
615 		return ret;
616 	}
617 
618 	return 0;
619 }
620 
621 static void wm8731_unregister(struct wm8731_priv *wm8731)
622 {
623 	wm8731_set_bias_level(&wm8731->codec, SND_SOC_BIAS_OFF);
624 	snd_soc_unregister_dai(&wm8731_dai);
625 	snd_soc_unregister_codec(&wm8731->codec);
626 	kfree(wm8731);
627 	wm8731_codec = NULL;
628 }
629 
630 #if defined(CONFIG_SPI_MASTER)
631 static int wm8731_spi_write(struct spi_device *spi, const char *data, int len)
632 {
633 	struct spi_transfer t;
634 	struct spi_message m;
635 	u8 msg[2];
636 
637 	if (len <= 0)
638 		return 0;
639 
640 	msg[0] = data[0];
641 	msg[1] = data[1];
642 
643 	spi_message_init(&m);
644 	memset(&t, 0, (sizeof t));
645 
646 	t.tx_buf = &msg[0];
647 	t.len = len;
648 
649 	spi_message_add_tail(&t, &m);
650 	spi_sync(spi, &m);
651 
652 	return len;
653 }
654 
655 static int __devinit wm8731_spi_probe(struct spi_device *spi)
656 {
657 	struct snd_soc_codec *codec;
658 	struct wm8731_priv *wm8731;
659 
660 	wm8731 = kzalloc(sizeof(struct wm8731_priv), GFP_KERNEL);
661 	if (wm8731 == NULL)
662 		return -ENOMEM;
663 
664 	codec = &wm8731->codec;
665 	codec->control_data = spi;
666 	codec->hw_write = (hw_write_t)wm8731_spi_write;
667 	codec->dev = &spi->dev;
668 
669 	spi->dev.driver_data = wm8731;
670 
671 	return wm8731_register(wm8731);
672 }
673 
674 static int __devexit wm8731_spi_remove(struct spi_device *spi)
675 {
676 	struct wm8731_priv *wm8731 = spi->dev.driver_data;
677 
678 	wm8731_unregister(wm8731);
679 
680 	return 0;
681 }
682 
683 static struct spi_driver wm8731_spi_driver = {
684 	.driver = {
685 		.name	= "wm8731",
686 		.bus	= &spi_bus_type,
687 		.owner	= THIS_MODULE,
688 	},
689 	.probe		= wm8731_spi_probe,
690 	.remove		= __devexit_p(wm8731_spi_remove),
691 };
692 #endif /* CONFIG_SPI_MASTER */
693 
694 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
695 static __devinit int wm8731_i2c_probe(struct i2c_client *i2c,
696 				      const struct i2c_device_id *id)
697 {
698 	struct wm8731_priv *wm8731;
699 	struct snd_soc_codec *codec;
700 
701 	wm8731 = kzalloc(sizeof(struct wm8731_priv), GFP_KERNEL);
702 	if (wm8731 == NULL)
703 		return -ENOMEM;
704 
705 	codec = &wm8731->codec;
706 	codec->hw_write = (hw_write_t)i2c_master_send;
707 
708 	i2c_set_clientdata(i2c, wm8731);
709 	codec->control_data = i2c;
710 
711 	codec->dev = &i2c->dev;
712 
713 	return wm8731_register(wm8731);
714 }
715 
716 static __devexit int wm8731_i2c_remove(struct i2c_client *client)
717 {
718 	struct wm8731_priv *wm8731 = i2c_get_clientdata(client);
719 	wm8731_unregister(wm8731);
720 	return 0;
721 }
722 
723 static const struct i2c_device_id wm8731_i2c_id[] = {
724 	{ "wm8731", 0 },
725 	{ }
726 };
727 MODULE_DEVICE_TABLE(i2c, wm8731_i2c_id);
728 
729 static struct i2c_driver wm8731_i2c_driver = {
730 	.driver = {
731 		.name = "WM8731 I2C Codec",
732 		.owner = THIS_MODULE,
733 	},
734 	.probe =    wm8731_i2c_probe,
735 	.remove =   __devexit_p(wm8731_i2c_remove),
736 	.id_table = wm8731_i2c_id,
737 };
738 #endif
739 
740 static int __init wm8731_modinit(void)
741 {
742 	int ret;
743 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
744 	ret = i2c_add_driver(&wm8731_i2c_driver);
745 	if (ret != 0) {
746 		printk(KERN_ERR "Failed to register WM8731 I2C driver: %d\n",
747 		       ret);
748 	}
749 #endif
750 #if defined(CONFIG_SPI_MASTER)
751 	ret = spi_register_driver(&wm8731_spi_driver);
752 	if (ret != 0) {
753 		printk(KERN_ERR "Failed to register WM8731 SPI driver: %d\n",
754 		       ret);
755 	}
756 #endif
757 	return 0;
758 }
759 module_init(wm8731_modinit);
760 
761 static void __exit wm8731_exit(void)
762 {
763 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
764 	i2c_del_driver(&wm8731_i2c_driver);
765 #endif
766 #if defined(CONFIG_SPI_MASTER)
767 	spi_unregister_driver(&wm8731_spi_driver);
768 #endif
769 }
770 module_exit(wm8731_exit);
771 
772 MODULE_DESCRIPTION("ASoC WM8731 driver");
773 MODULE_AUTHOR("Richard Purdie");
774 MODULE_LICENSE("GPL");
775