1 // SPDX-License-Identifier: GPL-2.0-only
3 * wm8731.c -- WM8731 ALSA SoC Audio driver
5 * Copyright 2005 Openedhand Ltd.
6 * Copyright 2006-12 Wolfson Microelectronics, plc
8 * Author: Richard Purdie <richard@openedhand.com>
10 * Based on wm8753.c by Liam Girdwood
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/init.h>
16 #include <linux/delay.h>
18 #include <linux/i2c.h>
19 #include <linux/slab.h>
20 #include <linux/regmap.h>
21 #include <linux/regulator/consumer.h>
22 #include <linux/spi/spi.h>
23 #include <linux/of_device.h>
24 #include <linux/mutex.h>
25 #include <linux/clk.h>
26 #include <sound/core.h>
27 #include <sound/pcm.h>
28 #include <sound/pcm_params.h>
29 #include <sound/soc.h>
30 #include <sound/initval.h>
31 #include <sound/tlv.h>
35 #define WM8731_NUM_SUPPLIES 4
36 static const char *wm8731_supply_names[WM8731_NUM_SUPPLIES] = {
43 /* codec private data */
45 struct regmap *regmap;
47 struct regulator_bulk_data supplies[WM8731_NUM_SUPPLIES];
48 const struct snd_pcm_hw_constraint_list *constraints;
59 * wm8731 register cache
61 static const struct reg_default wm8731_reg_defaults[] = {
74 static bool wm8731_volatile(struct device *dev, unsigned int reg)
76 return reg == WM8731_RESET;
79 #define wm8731_reset(m) regmap_write(m, WM8731_RESET, 0)
81 static const char *wm8731_input_select[] = {"Line In", "Mic"};
83 static SOC_ENUM_SINGLE_DECL(wm8731_insel_enum,
84 WM8731_APANA, 2, wm8731_input_select);
86 static int wm8731_deemph[] = { 0, 32000, 44100, 48000 };
88 static int wm8731_set_deemph(struct snd_soc_component *component)
90 struct wm8731_priv *wm8731 = snd_soc_component_get_drvdata(component);
93 /* If we're using deemphasis select the nearest available sample
98 for (i = 2; i < ARRAY_SIZE(wm8731_deemph); i++) {
99 if (abs(wm8731_deemph[i] - wm8731->playback_fs) <
100 abs(wm8731_deemph[best] - wm8731->playback_fs))
110 dev_dbg(component->dev, "Set deemphasis %d (%dHz)\n",
111 best, wm8731_deemph[best]);
113 return snd_soc_component_update_bits(component, WM8731_APDIGI, 0x6, val);
116 static int wm8731_get_deemph(struct snd_kcontrol *kcontrol,
117 struct snd_ctl_elem_value *ucontrol)
119 struct snd_soc_component *component = snd_soc_kcontrol_component(kcontrol);
120 struct wm8731_priv *wm8731 = snd_soc_component_get_drvdata(component);
122 ucontrol->value.integer.value[0] = wm8731->deemph;
127 static int wm8731_put_deemph(struct snd_kcontrol *kcontrol,
128 struct snd_ctl_elem_value *ucontrol)
130 struct snd_soc_component *component = snd_soc_kcontrol_component(kcontrol);
131 struct wm8731_priv *wm8731 = snd_soc_component_get_drvdata(component);
132 unsigned int deemph = ucontrol->value.integer.value[0];
138 mutex_lock(&wm8731->lock);
139 if (wm8731->deemph != deemph) {
140 wm8731->deemph = deemph;
142 wm8731_set_deemph(component);
146 mutex_unlock(&wm8731->lock);
151 static const DECLARE_TLV_DB_SCALE(in_tlv, -3450, 150, 0);
152 static const DECLARE_TLV_DB_SCALE(sidetone_tlv, -1500, 300, 0);
153 static const DECLARE_TLV_DB_SCALE(out_tlv, -12100, 100, 1);
154 static const DECLARE_TLV_DB_SCALE(mic_tlv, 0, 2000, 0);
156 static const struct snd_kcontrol_new wm8731_snd_controls[] = {
158 SOC_DOUBLE_R_TLV("Master Playback Volume", WM8731_LOUT1V, WM8731_ROUT1V,
160 SOC_DOUBLE_R("Master Playback ZC Switch", WM8731_LOUT1V, WM8731_ROUT1V,
163 SOC_DOUBLE_R_TLV("Capture Volume", WM8731_LINVOL, WM8731_RINVOL, 0, 31, 0,
165 SOC_DOUBLE_R("Line Capture Switch", WM8731_LINVOL, WM8731_RINVOL, 7, 1, 1),
167 SOC_SINGLE_TLV("Mic Boost Volume", WM8731_APANA, 0, 1, 0, mic_tlv),
168 SOC_SINGLE("Mic Capture Switch", WM8731_APANA, 1, 1, 1),
170 SOC_SINGLE_TLV("Sidetone Playback Volume", WM8731_APANA, 6, 3, 1,
173 SOC_SINGLE("ADC High Pass Filter Switch", WM8731_APDIGI, 0, 1, 1),
174 SOC_SINGLE("Store DC Offset Switch", WM8731_APDIGI, 4, 1, 0),
176 SOC_SINGLE_BOOL_EXT("Playback Deemphasis Switch", 0,
177 wm8731_get_deemph, wm8731_put_deemph),
181 static const struct snd_kcontrol_new wm8731_output_mixer_controls[] = {
182 SOC_DAPM_SINGLE("Line Bypass Switch", WM8731_APANA, 3, 1, 0),
183 SOC_DAPM_SINGLE("Mic Sidetone Switch", WM8731_APANA, 5, 1, 0),
184 SOC_DAPM_SINGLE("HiFi Playback Switch", WM8731_APANA, 4, 1, 0),
188 static const struct snd_kcontrol_new wm8731_input_mux_controls =
189 SOC_DAPM_ENUM("Input Select", wm8731_insel_enum);
191 static const struct snd_soc_dapm_widget wm8731_dapm_widgets[] = {
192 SND_SOC_DAPM_SUPPLY("ACTIVE",WM8731_ACTIVE, 0, 0, NULL, 0),
193 SND_SOC_DAPM_SUPPLY("OSC", WM8731_PWR, 5, 1, NULL, 0),
194 SND_SOC_DAPM_MIXER("Output Mixer", WM8731_PWR, 4, 1,
195 &wm8731_output_mixer_controls[0],
196 ARRAY_SIZE(wm8731_output_mixer_controls)),
197 SND_SOC_DAPM_DAC("DAC", "HiFi Playback", WM8731_PWR, 3, 1),
198 SND_SOC_DAPM_OUTPUT("LOUT"),
199 SND_SOC_DAPM_OUTPUT("LHPOUT"),
200 SND_SOC_DAPM_OUTPUT("ROUT"),
201 SND_SOC_DAPM_OUTPUT("RHPOUT"),
202 SND_SOC_DAPM_ADC("ADC", "HiFi Capture", WM8731_PWR, 2, 1),
203 SND_SOC_DAPM_MUX("Input Mux", SND_SOC_NOPM, 0, 0, &wm8731_input_mux_controls),
204 SND_SOC_DAPM_PGA("Line Input", WM8731_PWR, 0, 1, NULL, 0),
205 SND_SOC_DAPM_MICBIAS("Mic Bias", WM8731_PWR, 1, 1),
206 SND_SOC_DAPM_INPUT("MICIN"),
207 SND_SOC_DAPM_INPUT("RLINEIN"),
208 SND_SOC_DAPM_INPUT("LLINEIN"),
211 static int wm8731_check_osc(struct snd_soc_dapm_widget *source,
212 struct snd_soc_dapm_widget *sink)
214 struct snd_soc_component *component = snd_soc_dapm_to_component(source->dapm);
215 struct wm8731_priv *wm8731 = snd_soc_component_get_drvdata(component);
217 return wm8731->sysclk_type == WM8731_SYSCLK_XTAL;
220 static const struct snd_soc_dapm_route wm8731_intercon[] = {
221 {"DAC", NULL, "OSC", wm8731_check_osc},
222 {"ADC", NULL, "OSC", wm8731_check_osc},
223 {"DAC", NULL, "ACTIVE"},
224 {"ADC", NULL, "ACTIVE"},
227 {"Output Mixer", "Line Bypass Switch", "Line Input"},
228 {"Output Mixer", "HiFi Playback Switch", "DAC"},
229 {"Output Mixer", "Mic Sidetone Switch", "Mic Bias"},
232 {"RHPOUT", NULL, "Output Mixer"},
233 {"ROUT", NULL, "Output Mixer"},
234 {"LHPOUT", NULL, "Output Mixer"},
235 {"LOUT", NULL, "Output Mixer"},
238 {"Input Mux", "Line In", "Line Input"},
239 {"Input Mux", "Mic", "Mic Bias"},
240 {"ADC", NULL, "Input Mux"},
243 {"Line Input", NULL, "LLINEIN"},
244 {"Line Input", NULL, "RLINEIN"},
245 {"Mic Bias", NULL, "MICIN"},
257 /* codec mclk clock divider coefficients */
258 static const struct _coeff_div coeff_div[] = {
260 {12288000, 48000, 256, 0x0, 0x0, 0x0},
261 {18432000, 48000, 384, 0x0, 0x1, 0x0},
262 {12000000, 48000, 250, 0x0, 0x0, 0x1},
265 {12288000, 32000, 384, 0x6, 0x0, 0x0},
266 {18432000, 32000, 576, 0x6, 0x1, 0x0},
267 {12000000, 32000, 375, 0x6, 0x0, 0x1},
270 {12288000, 8000, 1536, 0x3, 0x0, 0x0},
271 {18432000, 8000, 2304, 0x3, 0x1, 0x0},
272 {11289600, 8000, 1408, 0xb, 0x0, 0x0},
273 {16934400, 8000, 2112, 0xb, 0x1, 0x0},
274 {12000000, 8000, 1500, 0x3, 0x0, 0x1},
277 {12288000, 96000, 128, 0x7, 0x0, 0x0},
278 {18432000, 96000, 192, 0x7, 0x1, 0x0},
279 {12000000, 96000, 125, 0x7, 0x0, 0x1},
282 {11289600, 44100, 256, 0x8, 0x0, 0x0},
283 {16934400, 44100, 384, 0x8, 0x1, 0x0},
284 {12000000, 44100, 272, 0x8, 0x1, 0x1},
287 {11289600, 88200, 128, 0xf, 0x0, 0x0},
288 {16934400, 88200, 192, 0xf, 0x1, 0x0},
289 {12000000, 88200, 136, 0xf, 0x1, 0x1},
292 /* rates constraints */
293 static const unsigned int wm8731_rates_12000000[] = {
294 8000, 32000, 44100, 48000, 96000, 88200,
297 static const unsigned int wm8731_rates_12288000_18432000[] = {
298 8000, 32000, 48000, 96000,
301 static const unsigned int wm8731_rates_11289600_16934400[] = {
305 static const struct snd_pcm_hw_constraint_list wm8731_constraints_12000000 = {
306 .list = wm8731_rates_12000000,
307 .count = ARRAY_SIZE(wm8731_rates_12000000),
311 struct snd_pcm_hw_constraint_list wm8731_constraints_12288000_18432000 = {
312 .list = wm8731_rates_12288000_18432000,
313 .count = ARRAY_SIZE(wm8731_rates_12288000_18432000),
317 struct snd_pcm_hw_constraint_list wm8731_constraints_11289600_16934400 = {
318 .list = wm8731_rates_11289600_16934400,
319 .count = ARRAY_SIZE(wm8731_rates_11289600_16934400),
322 static inline int get_coeff(int mclk, int rate)
326 for (i = 0; i < ARRAY_SIZE(coeff_div); i++) {
327 if (coeff_div[i].rate == rate && coeff_div[i].mclk == mclk)
333 static int wm8731_hw_params(struct snd_pcm_substream *substream,
334 struct snd_pcm_hw_params *params,
335 struct snd_soc_dai *dai)
337 struct snd_soc_component *component = dai->component;
338 struct wm8731_priv *wm8731 = snd_soc_component_get_drvdata(component);
339 u16 iface = snd_soc_component_read(component, WM8731_IFACE) & 0xfff3;
340 int i = get_coeff(wm8731->sysclk, params_rate(params));
341 u16 srate = (coeff_div[i].sr << 2) |
342 (coeff_div[i].bosr << 1) | coeff_div[i].usb;
344 wm8731->playback_fs = params_rate(params);
346 snd_soc_component_write(component, WM8731_SRATE, srate);
349 switch (params_width(params)) {
363 wm8731_set_deemph(component);
365 snd_soc_component_write(component, WM8731_IFACE, iface);
369 static int wm8731_mute(struct snd_soc_dai *dai, int mute, int direction)
371 struct snd_soc_component *component = dai->component;
372 u16 mute_reg = snd_soc_component_read(component, WM8731_APDIGI) & 0xfff7;
375 snd_soc_component_write(component, WM8731_APDIGI, mute_reg | 0x8);
377 snd_soc_component_write(component, WM8731_APDIGI, mute_reg);
381 static int wm8731_set_dai_sysclk(struct snd_soc_dai *codec_dai,
382 int clk_id, unsigned int freq, int dir)
384 struct snd_soc_component *component = codec_dai->component;
385 struct snd_soc_dapm_context *dapm = snd_soc_component_get_dapm(component);
386 struct wm8731_priv *wm8731 = snd_soc_component_get_drvdata(component);
389 case WM8731_SYSCLK_XTAL:
390 case WM8731_SYSCLK_MCLK:
391 if (wm8731->mclk && clk_set_rate(wm8731->mclk, freq))
393 wm8731->sysclk_type = clk_id;
401 wm8731->constraints = NULL;
404 wm8731->constraints = &wm8731_constraints_12000000;
408 wm8731->constraints = &wm8731_constraints_12288000_18432000;
412 wm8731->constraints = &wm8731_constraints_11289600_16934400;
418 wm8731->sysclk = freq;
420 snd_soc_dapm_sync(dapm);
426 static int wm8731_set_dai_fmt(struct snd_soc_dai *codec_dai,
429 struct snd_soc_component *component = codec_dai->component;
432 /* set master/slave audio interface */
433 switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
434 case SND_SOC_DAIFMT_CBM_CFM:
437 case SND_SOC_DAIFMT_CBS_CFS:
443 /* interface format */
444 switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
445 case SND_SOC_DAIFMT_I2S:
448 case SND_SOC_DAIFMT_RIGHT_J:
450 case SND_SOC_DAIFMT_LEFT_J:
453 case SND_SOC_DAIFMT_DSP_A:
456 case SND_SOC_DAIFMT_DSP_B:
463 /* clock inversion */
464 switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
465 case SND_SOC_DAIFMT_NB_NF:
467 case SND_SOC_DAIFMT_IB_IF:
470 case SND_SOC_DAIFMT_IB_NF:
473 case SND_SOC_DAIFMT_NB_IF:
481 snd_soc_component_write(component, WM8731_IFACE, iface);
485 static int wm8731_set_bias_level(struct snd_soc_component *component,
486 enum snd_soc_bias_level level)
488 struct wm8731_priv *wm8731 = snd_soc_component_get_drvdata(component);
493 case SND_SOC_BIAS_ON:
495 ret = clk_prepare_enable(wm8731->mclk);
500 case SND_SOC_BIAS_PREPARE:
502 case SND_SOC_BIAS_STANDBY:
503 if (snd_soc_component_get_bias_level(component) == SND_SOC_BIAS_OFF) {
504 ret = regulator_bulk_enable(ARRAY_SIZE(wm8731->supplies),
509 regcache_sync(wm8731->regmap);
512 /* Clear PWROFF, gate CLKOUT, everything else as-is */
513 reg = snd_soc_component_read(component, WM8731_PWR) & 0xff7f;
514 snd_soc_component_write(component, WM8731_PWR, reg | 0x0040);
516 case SND_SOC_BIAS_OFF:
518 clk_disable_unprepare(wm8731->mclk);
519 snd_soc_component_write(component, WM8731_PWR, 0xffff);
520 regulator_bulk_disable(ARRAY_SIZE(wm8731->supplies),
522 regcache_mark_dirty(wm8731->regmap);
528 static int wm8731_startup(struct snd_pcm_substream *substream,
529 struct snd_soc_dai *dai)
531 struct wm8731_priv *wm8731 = snd_soc_component_get_drvdata(dai->component);
533 if (wm8731->constraints)
534 snd_pcm_hw_constraint_list(substream->runtime, 0,
535 SNDRV_PCM_HW_PARAM_RATE,
536 wm8731->constraints);
541 #define WM8731_RATES SNDRV_PCM_RATE_8000_96000
543 #define WM8731_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE |\
544 SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
546 static const struct snd_soc_dai_ops wm8731_dai_ops = {
547 .startup = wm8731_startup,
548 .hw_params = wm8731_hw_params,
549 .mute_stream = wm8731_mute,
550 .set_sysclk = wm8731_set_dai_sysclk,
551 .set_fmt = wm8731_set_dai_fmt,
552 .no_capture_mute = 1,
555 static struct snd_soc_dai_driver wm8731_dai = {
556 .name = "wm8731-hifi",
558 .stream_name = "Playback",
561 .rates = WM8731_RATES,
562 .formats = WM8731_FORMATS,},
564 .stream_name = "Capture",
567 .rates = WM8731_RATES,
568 .formats = WM8731_FORMATS,},
569 .ops = &wm8731_dai_ops,
573 static int wm8731_request_supplies(struct device *dev,
574 struct wm8731_priv *wm8731)
578 for (i = 0; i < ARRAY_SIZE(wm8731->supplies); i++)
579 wm8731->supplies[i].supply = wm8731_supply_names[i];
581 ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(wm8731->supplies),
584 dev_err(dev, "Failed to request supplies: %d\n", ret);
588 ret = regulator_bulk_enable(ARRAY_SIZE(wm8731->supplies),
591 dev_err(dev, "Failed to enable supplies: %d\n", ret);
598 static int wm8731_hw_init(struct device *dev, struct wm8731_priv *wm8731)
602 ret = wm8731_reset(wm8731->regmap);
604 dev_err(dev, "Failed to issue reset: %d\n", ret);
605 goto err_regulator_enable;
608 /* Clear POWEROFF, keep everything else disabled */
609 regmap_write(wm8731->regmap, WM8731_PWR, 0x7f);
611 /* Latch the update bits */
612 regmap_update_bits(wm8731->regmap, WM8731_LOUT1V, 0x100, 0);
613 regmap_update_bits(wm8731->regmap, WM8731_ROUT1V, 0x100, 0);
614 regmap_update_bits(wm8731->regmap, WM8731_LINVOL, 0x100, 0);
615 regmap_update_bits(wm8731->regmap, WM8731_RINVOL, 0x100, 0);
617 /* Disable bypass path by default */
618 regmap_update_bits(wm8731->regmap, WM8731_APANA, 0x8, 0);
620 regcache_mark_dirty(wm8731->regmap);
622 err_regulator_enable:
623 /* Regulators will be enabled by bias management */
624 regulator_bulk_disable(ARRAY_SIZE(wm8731->supplies), wm8731->supplies);
629 static const struct snd_soc_component_driver soc_component_dev_wm8731 = {
630 .set_bias_level = wm8731_set_bias_level,
631 .controls = wm8731_snd_controls,
632 .num_controls = ARRAY_SIZE(wm8731_snd_controls),
633 .dapm_widgets = wm8731_dapm_widgets,
634 .num_dapm_widgets = ARRAY_SIZE(wm8731_dapm_widgets),
635 .dapm_routes = wm8731_intercon,
636 .num_dapm_routes = ARRAY_SIZE(wm8731_intercon),
637 .suspend_bias_off = 1,
639 .use_pmdown_time = 1,
641 .non_legacy_dai_naming = 1,
644 static const struct of_device_id wm8731_of_match[] = {
645 { .compatible = "wlf,wm8731", },
649 MODULE_DEVICE_TABLE(of, wm8731_of_match);
651 static const struct regmap_config wm8731_regmap = {
655 .max_register = WM8731_RESET,
656 .volatile_reg = wm8731_volatile,
658 .cache_type = REGCACHE_RBTREE,
659 .reg_defaults = wm8731_reg_defaults,
660 .num_reg_defaults = ARRAY_SIZE(wm8731_reg_defaults),
663 #if defined(CONFIG_SPI_MASTER)
664 static int wm8731_spi_probe(struct spi_device *spi)
666 struct wm8731_priv *wm8731;
669 wm8731 = devm_kzalloc(&spi->dev, sizeof(*wm8731), GFP_KERNEL);
673 wm8731->mclk = devm_clk_get(&spi->dev, "mclk");
674 if (IS_ERR(wm8731->mclk)) {
675 ret = PTR_ERR(wm8731->mclk);
676 if (ret == -ENOENT) {
678 dev_warn(&spi->dev, "Assuming static MCLK\n");
680 dev_err(&spi->dev, "Failed to get MCLK: %d\n",
686 mutex_init(&wm8731->lock);
688 spi_set_drvdata(spi, wm8731);
690 ret = wm8731_request_supplies(&spi->dev, wm8731);
694 wm8731->regmap = devm_regmap_init_spi(spi, &wm8731_regmap);
695 if (IS_ERR(wm8731->regmap)) {
696 ret = PTR_ERR(wm8731->regmap);
697 dev_err(&spi->dev, "Failed to allocate register map: %d\n",
702 ret = wm8731_hw_init(&spi->dev, wm8731);
706 ret = devm_snd_soc_register_component(&spi->dev,
707 &soc_component_dev_wm8731, &wm8731_dai, 1);
709 dev_err(&spi->dev, "Failed to register CODEC: %d\n", ret);
716 static struct spi_driver wm8731_spi_driver = {
719 .of_match_table = wm8731_of_match,
721 .probe = wm8731_spi_probe,
723 #endif /* CONFIG_SPI_MASTER */
725 #if IS_ENABLED(CONFIG_I2C)
726 static int wm8731_i2c_probe(struct i2c_client *i2c,
727 const struct i2c_device_id *id)
729 struct wm8731_priv *wm8731;
732 wm8731 = devm_kzalloc(&i2c->dev, sizeof(struct wm8731_priv),
737 wm8731->mclk = devm_clk_get(&i2c->dev, "mclk");
738 if (IS_ERR(wm8731->mclk)) {
739 ret = PTR_ERR(wm8731->mclk);
740 if (ret == -ENOENT) {
742 dev_warn(&i2c->dev, "Assuming static MCLK\n");
744 dev_err(&i2c->dev, "Failed to get MCLK: %d\n",
750 mutex_init(&wm8731->lock);
752 i2c_set_clientdata(i2c, wm8731);
754 ret = wm8731_request_supplies(&i2c->dev, wm8731);
758 wm8731->regmap = devm_regmap_init_i2c(i2c, &wm8731_regmap);
759 if (IS_ERR(wm8731->regmap)) {
760 ret = PTR_ERR(wm8731->regmap);
761 dev_err(&i2c->dev, "Failed to allocate register map: %d\n",
766 ret = wm8731_hw_init(&i2c->dev, wm8731);
770 ret = devm_snd_soc_register_component(&i2c->dev,
771 &soc_component_dev_wm8731, &wm8731_dai, 1);
773 dev_err(&i2c->dev, "Failed to register CODEC: %d\n", ret);
780 static int wm8731_i2c_remove(struct i2c_client *client)
785 static const struct i2c_device_id wm8731_i2c_id[] = {
789 MODULE_DEVICE_TABLE(i2c, wm8731_i2c_id);
791 static struct i2c_driver wm8731_i2c_driver = {
794 .of_match_table = wm8731_of_match,
796 .probe = wm8731_i2c_probe,
797 .remove = wm8731_i2c_remove,
798 .id_table = wm8731_i2c_id,
802 static int __init wm8731_modinit(void)
805 #if IS_ENABLED(CONFIG_I2C)
806 ret = i2c_add_driver(&wm8731_i2c_driver);
808 printk(KERN_ERR "Failed to register WM8731 I2C driver: %d\n",
812 #if defined(CONFIG_SPI_MASTER)
813 ret = spi_register_driver(&wm8731_spi_driver);
815 printk(KERN_ERR "Failed to register WM8731 SPI driver: %d\n",
821 module_init(wm8731_modinit);
823 static void __exit wm8731_exit(void)
825 #if IS_ENABLED(CONFIG_I2C)
826 i2c_del_driver(&wm8731_i2c_driver);
828 #if defined(CONFIG_SPI_MASTER)
829 spi_unregister_driver(&wm8731_spi_driver);
832 module_exit(wm8731_exit);
834 MODULE_DESCRIPTION("ASoC WM8731 driver");
835 MODULE_AUTHOR("Richard Purdie");
836 MODULE_LICENSE("GPL");