ASoC: WM8770: Initial driver

The WM8770 is a high performance, multi-channel audio
codec. The WM8770 is ideal for surround sound processing
applications for home hi-fi, automotive and other audio
visual equipment.

Signed-off-by: Dimitris Papastamos <[e-mail]>
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/codecs/Kconfig

···
 	select SND_SOC_WM8741 if SND_SOC_I2C_AND_SPI
 	select SND_SOC_WM8750 if SND_SOC_I2C_AND_SPI
 	select SND_SOC_WM8753 if SND_SOC_I2C_AND_SPI
+	select SND_SOC_WM8770 if SPI_MASTER
 	select SND_SOC_WM8776 if SND_SOC_I2C_AND_SPI
 	select SND_SOC_WM8804 if SND_SOC_I2C_AND_SPI
 	select SND_SOC_WM8900 if I2C
···
 	tristate
 
 config SND_SOC_WM8753
+	tristate
+
+config SND_SOC_WM8770
 	tristate
 
 config SND_SOC_WM8776

sound/soc/codecs/Makefile

···
 snd-soc-wm8741-objs := wm8741.o
 snd-soc-wm8750-objs := wm8750.o
 snd-soc-wm8753-objs := wm8753.o
+snd-soc-wm8770-objs := wm8770.o
 snd-soc-wm8776-objs := wm8776.o
 snd-soc-wm8804-objs := wm8804.o
 snd-soc-wm8900-objs := wm8900.o
···
 obj-$(CONFIG_SND_SOC_WM8741)	+= snd-soc-wm8741.o
 obj-$(CONFIG_SND_SOC_WM8750)	+= snd-soc-wm8750.o
 obj-$(CONFIG_SND_SOC_WM8753)	+= snd-soc-wm8753.o
+obj-$(CONFIG_SND_SOC_WM8770)	+= snd-soc-wm8770.o
 obj-$(CONFIG_SND_SOC_WM8776)	+= snd-soc-wm8776.o
 obj-$(CONFIG_SND_SOC_WM8804)	+= snd-soc-wm8804.o
 obj-$(CONFIG_SND_SOC_WM8900)	+= snd-soc-wm8900.o

sound/soc/codecs/wm8770.c

···
+/*
+ * wm8770.c  --  WM8770 ALSA SoC Audio driver
+ *
+ * Copyright 2010 Wolfson Microelectronics plc
+ *
+ * Author: Dimitris Papastamos <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/pm.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/soc-dapm.h>
+#include <sound/initval.h>
+#include <sound/tlv.h>
+
+#include "wm8770.h"
+
+#define WM8770_NUM_SUPPLIES 3
+static const char *wm8770_supply_names[WM8770_NUM_SUPPLIES] = {
+	"AVDD1",
+	"AVDD2",
+	"DVDD"
+};
+
+static const u16 wm8770_reg_defs[WM8770_CACHEREGNUM] = {
+	0x7f, 0x7f, 0x7f, 0x7f,
+	0x7f, 0x7f, 0x7f, 0x7f,
+	0x7f, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0, 0x90, 0,
+	0, 0x22, 0x22, 0x3e,
+	0xc, 0xc, 0x100, 0x189,
+	0x189, 0x8770
+};
+
+struct wm8770_priv {
+	enum snd_soc_control_type control_type;
+	struct regulator_bulk_data supplies[WM8770_NUM_SUPPLIES];
+	struct notifier_block disable_nb[WM8770_NUM_SUPPLIES];
+	struct snd_soc_codec *codec;
+	int sysclk;
+};
+
+static int vout12supply_event(struct snd_soc_dapm_widget *w,
+	struct snd_kcontrol *kcontrol, int event);
+static int vout34supply_event(struct snd_soc_dapm_widget *w,
+	struct snd_kcontrol *kcontrol, int event);
+
+/*
+ * We can't use the same notifier block for more than one supply and
+ * there's no way I can see to get from a callback to the caller
+ * except container_of().
+ */
+#define WM8770_REGULATOR_EVENT(n) \
+static int wm8770_regulator_event_##n(struct notifier_block *nb, \
+				      unsigned long event, void *data)    \
+{ \
+	struct wm8770_priv *wm8770 = container_of(nb, struct wm8770_priv, \
+				     disable_nb[n]); \
+	if (event & REGULATOR_EVENT_DISABLE) { \
+		wm8770->codec->cache_sync = 1; \
+	} \
+	return 0; \
+}
+
+WM8770_REGULATOR_EVENT(0)
+WM8770_REGULATOR_EVENT(1)
+WM8770_REGULATOR_EVENT(2)
+
+static const DECLARE_TLV_DB_SCALE(adc_tlv, -1200, 100, 0);
+static const DECLARE_TLV_DB_SCALE(dac_dig_tlv, -12750, 50, 1);
+static const DECLARE_TLV_DB_SCALE(dac_alg_tlv, -12700, 100, 1);
+
+static const char *dac_phase_text[][2] = {
+	{ "DAC1 Normal", "DAC1 Inverted" },
+	{ "DAC2 Normal", "DAC2 Inverted" },
+	{ "DAC3 Normal", "DAC3 Inverted" },
+	{ "DAC4 Normal", "DAC4 Inverted" },
+};
+
+static const struct soc_enum dac_phase[] = {
+	SOC_ENUM_DOUBLE(WM8770_DACPHASE, 0, 1, 2, dac_phase_text[0]),
+	SOC_ENUM_DOUBLE(WM8770_DACPHASE, 2, 3, 2, dac_phase_text[1]),
+	SOC_ENUM_DOUBLE(WM8770_DACPHASE, 4, 5, 2, dac_phase_text[2]),
+	SOC_ENUM_DOUBLE(WM8770_DACPHASE, 6, 7, 2, dac_phase_text[3]),
+};
+
+static const struct snd_kcontrol_new wm8770_snd_controls[] = {
+	/* global DAC playback controls */
+	SOC_SINGLE_TLV("DAC Playback Volume", WM8770_MSDIGVOL, 0, 255, 0,
+		dac_dig_tlv),
+	SOC_SINGLE("DAC Playback Switch", WM8770_DACMUTE, 4, 1, 1),
+	SOC_SINGLE("DAC Playback ZC Switch", WM8770_DACCTRL1, 0, 1, 0),
+
+	/* global VOUT playback controls */
+	SOC_SINGLE_TLV("VOUT Playback Volume", WM8770_MSALGVOL, 0, 127, 0,
+		dac_alg_tlv),
+	SOC_SINGLE("VOUT Playback ZC Switch", WM8770_MSALGVOL, 7, 1, 0),
+
+	/* VOUT1/2/3/4 specific controls */
+	SOC_DOUBLE_R_TLV("VOUT1 Playback Volume", WM8770_VOUT1LVOL,
+		WM8770_VOUT1RVOL, 0, 127, 0, dac_alg_tlv),
+	SOC_DOUBLE_R("VOUT1 Playback ZC Switch", WM8770_VOUT1LVOL,
+		WM8770_VOUT1RVOL, 7, 1, 0),
+	SOC_DOUBLE_R_TLV("VOUT2 Playback Volume", WM8770_VOUT2LVOL,
+		WM8770_VOUT2RVOL, 0, 127, 0, dac_alg_tlv),
+	SOC_DOUBLE_R("VOUT2 Playback ZC Switch", WM8770_VOUT2LVOL,
+		WM8770_VOUT2RVOL, 7, 1, 0),
+	SOC_DOUBLE_R_TLV("VOUT3 Playback Volume", WM8770_VOUT3LVOL,
+		WM8770_VOUT3RVOL, 0, 127, 0, dac_alg_tlv),
+	SOC_DOUBLE_R("VOUT3 Playback ZC Switch", WM8770_VOUT3LVOL,
+		WM8770_VOUT3RVOL, 7, 1, 0),
+	SOC_DOUBLE_R_TLV("VOUT4 Playback Volume", WM8770_VOUT4LVOL,
+		WM8770_VOUT4RVOL, 0, 127, 0, dac_alg_tlv),
+	SOC_DOUBLE_R("VOUT4 Playback ZC Switch", WM8770_VOUT4LVOL,
+		WM8770_VOUT4RVOL, 7, 1, 0),
+
+	/* DAC1/2/3/4 specific controls */
+	SOC_DOUBLE_R_TLV("DAC1 Playback Volume", WM8770_DAC1LVOL,
+		WM8770_DAC1RVOL, 0, 255, 0, dac_dig_tlv),
+	SOC_SINGLE("DAC1 Deemphasis Switch", WM8770_DACCTRL2, 0, 1, 0),
+	SOC_ENUM("DAC1 Phase", dac_phase[0]),
+	SOC_DOUBLE_R_TLV("DAC2 Playback Volume", WM8770_DAC2LVOL,
+		WM8770_DAC2RVOL, 0, 255, 0, dac_dig_tlv),
+	SOC_SINGLE("DAC2 Deemphasis Switch", WM8770_DACCTRL2, 1, 1, 0),
+	SOC_ENUM("DAC2 Phase", dac_phase[1]),
+	SOC_DOUBLE_R_TLV("DAC3 Playback Volume", WM8770_DAC3LVOL,
+		WM8770_DAC3RVOL, 0, 255, 0, dac_dig_tlv),
+	SOC_SINGLE("DAC3 Deemphasis Switch", WM8770_DACCTRL2, 2, 1, 0),
+	SOC_ENUM("DAC3 Phase", dac_phase[2]),
+	SOC_DOUBLE_R_TLV("DAC4 Playback Volume", WM8770_DAC4LVOL,
+		WM8770_DAC4RVOL, 0, 255, 0, dac_dig_tlv),
+	SOC_SINGLE("DAC4 Deemphasis Switch", WM8770_DACCTRL2, 3, 1, 0),
+	SOC_ENUM("DAC4 Phase", dac_phase[3]),
+
+	/* ADC specific controls */
+	SOC_DOUBLE_R_TLV("Capture Volume", WM8770_ADCLCTRL, WM8770_ADCRCTRL,
+		0, 31, 0, adc_tlv),
+	SOC_DOUBLE_R("Capture Switch", WM8770_ADCLCTRL, WM8770_ADCRCTRL,
+		5, 1, 1),
+
+	/* other controls */
+	SOC_SINGLE("ADC 128x Oversampling Switch", WM8770_MSTRCTRL, 3, 1, 0),
+	SOC_SINGLE("ADC Highpass Filter Switch", WM8770_IFACECTRL, 8, 1, 1)
+};
+
+static const char *ain_text[] = {
+	"AIN1", "AIN2", "AIN3", "AIN4",
+	"AIN5", "AIN6", "AIN7", "AIN8"
+};
+
+static const struct soc_enum ain_enum =
+	SOC_ENUM_DOUBLE(WM8770_ADCMUX, 0, 4, 8, ain_text);
+
+static const struct snd_kcontrol_new ain_mux =
+	SOC_DAPM_ENUM("Capture Mux", ain_enum);
+
+static const struct snd_kcontrol_new vout1_mix_controls[] = {
+	SOC_DAPM_SINGLE("DAC1 Switch", WM8770_OUTMUX1, 0, 1, 0),
+	SOC_DAPM_SINGLE("AUX1 Switch", WM8770_OUTMUX1, 1, 1, 0),
+	SOC_DAPM_SINGLE("Bypass Switch", WM8770_OUTMUX1, 2, 1, 0)
+};
+
+static const struct snd_kcontrol_new vout2_mix_controls[] = {
+	SOC_DAPM_SINGLE("DAC2 Switch", WM8770_OUTMUX1, 3, 1, 0),
+	SOC_DAPM_SINGLE("AUX2 Switch", WM8770_OUTMUX1, 4, 1, 0),
+	SOC_DAPM_SINGLE("Bypass Switch", WM8770_OUTMUX1, 5, 1, 0)
+};
+
+static const struct snd_kcontrol_new vout3_mix_controls[] = {
+	SOC_DAPM_SINGLE("DAC3 Switch", WM8770_OUTMUX2, 0, 1, 0),
+	SOC_DAPM_SINGLE("AUX3 Switch", WM8770_OUTMUX2, 1, 1, 0),
+	SOC_DAPM_SINGLE("Bypass Switch", WM8770_OUTMUX2, 2, 1, 0)
+};
+
+static const struct snd_kcontrol_new vout4_mix_controls[] = {
+	SOC_DAPM_SINGLE("DAC4 Switch", WM8770_OUTMUX2, 3, 1, 0),
+	SOC_DAPM_SINGLE("Bypass Switch", WM8770_OUTMUX2, 4, 1, 0)
+};
+
+static const struct snd_soc_dapm_widget wm8770_dapm_widgets[] = {
+	SND_SOC_DAPM_INPUT("AUX1"),
+	SND_SOC_DAPM_INPUT("AUX2"),
+	SND_SOC_DAPM_INPUT("AUX3"),
+
+	SND_SOC_DAPM_INPUT("AIN1"),
+	SND_SOC_DAPM_INPUT("AIN2"),
+	SND_SOC_DAPM_INPUT("AIN3"),
+	SND_SOC_DAPM_INPUT("AIN4"),
+	SND_SOC_DAPM_INPUT("AIN5"),
+	SND_SOC_DAPM_INPUT("AIN6"),
+	SND_SOC_DAPM_INPUT("AIN7"),
+	SND_SOC_DAPM_INPUT("AIN8"),
+
+	SND_SOC_DAPM_MUX("Capture Mux", WM8770_ADCMUX, 8, 1, &ain_mux),
+
+	SND_SOC_DAPM_ADC("ADC", "Capture", WM8770_PWDNCTRL, 1, 1),
+
+	SND_SOC_DAPM_DAC("DAC1", "Playback", WM8770_PWDNCTRL, 2, 1),
+	SND_SOC_DAPM_DAC("DAC2", "Playback", WM8770_PWDNCTRL, 3, 1),
+	SND_SOC_DAPM_DAC("DAC3", "Playback", WM8770_PWDNCTRL, 4, 1),
+	SND_SOC_DAPM_DAC("DAC4", "Playback", WM8770_PWDNCTRL, 5, 1),
+
+	SND_SOC_DAPM_SUPPLY("VOUT12 Supply", SND_SOC_NOPM, 0, 0,
+		vout12supply_event, SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMD),
+	SND_SOC_DAPM_SUPPLY("VOUT34 Supply", SND_SOC_NOPM, 0, 0,
+		vout34supply_event, SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMD),
+
+	SND_SOC_DAPM_MIXER("VOUT1 Mixer", SND_SOC_NOPM, 0, 0,
+		vout1_mix_controls, ARRAY_SIZE(vout1_mix_controls)),
+	SND_SOC_DAPM_MIXER("VOUT2 Mixer", SND_SOC_NOPM, 0, 0,
+		vout2_mix_controls, ARRAY_SIZE(vout2_mix_controls)),
+	SND_SOC_DAPM_MIXER("VOUT3 Mixer", SND_SOC_NOPM, 0, 0,
+		vout3_mix_controls, ARRAY_SIZE(vout3_mix_controls)),
+	SND_SOC_DAPM_MIXER("VOUT4 Mixer", SND_SOC_NOPM, 0, 0,
+		vout4_mix_controls, ARRAY_SIZE(vout4_mix_controls)),
+
+	SND_SOC_DAPM_OUTPUT("VOUT1"),
+	SND_SOC_DAPM_OUTPUT("VOUT2"),
+	SND_SOC_DAPM_OUTPUT("VOUT3"),
+	SND_SOC_DAPM_OUTPUT("VOUT4")
+};
+
+static const struct snd_soc_dapm_route wm8770_intercon[] = {
+	{ "Capture Mux", "AIN1", "AIN1" },
+	{ "Capture Mux", "AIN2", "AIN2" },
+	{ "Capture Mux", "AIN3", "AIN3" },
+	{ "Capture Mux", "AIN4", "AIN4" },
+	{ "Capture Mux", "AIN5", "AIN5" },
+	{ "Capture Mux", "AIN6", "AIN6" },
+	{ "Capture Mux", "AIN7", "AIN7" },
+	{ "Capture Mux", "AIN8", "AIN8" },
+
+	{ "ADC", NULL, "Capture Mux" },
+
+	{ "VOUT1 Mixer", NULL, "VOUT12 Supply" },
+	{ "VOUT1 Mixer", "DAC1 Switch", "DAC1" },
+	{ "VOUT1 Mixer", "AUX1 Switch", "AUX1" },
+	{ "VOUT1 Mixer", "Bypass Switch", "Capture Mux" },
+
+	{ "VOUT2 Mixer", NULL, "VOUT12 Supply" },
+	{ "VOUT2 Mixer", "DAC2 Switch", "DAC2" },
+	{ "VOUT2 Mixer", "AUX2 Switch", "AUX2" },
+	{ "VOUT2 Mixer", "Bypass Switch", "Capture Mux" },
+
+	{ "VOUT3 Mixer", NULL, "VOUT34 Supply" },
+	{ "VOUT3 Mixer", "DAC3 Switch", "DAC3" },
+	{ "VOUT3 Mixer", "AUX3 Switch", "AUX3" },
+	{ "VOUT3 Mixer", "Bypass Switch", "Capture Mux" },
+
+	{ "VOUT4 Mixer", NULL, "VOUT34 Supply" },
+	{ "VOUT4 Mixer", "DAC4 Switch", "DAC4" },
+	{ "VOUT4 Mixer", "Bypass Switch", "Capture Mux" },
+
+	{ "VOUT1", NULL, "VOUT1 Mixer" },
+	{ "VOUT2", NULL, "VOUT2 Mixer" },
+	{ "VOUT3", NULL, "VOUT3 Mixer" },
+	{ "VOUT4", NULL, "VOUT4 Mixer" }
+};
+
+static int vout12supply_event(struct snd_soc_dapm_widget *w,
+	struct snd_kcontrol *kcontrol, int event)
+{
+	struct snd_soc_codec *codec;
+
+	codec = w->codec;
+
+	switch (event) {
+	case SND_SOC_DAPM_PRE_PMU:
+		snd_soc_update_bits(codec, WM8770_OUTMUX1, 0x180, 0);
+		break;
+	case SND_SOC_DAPM_POST_PMD:
+		snd_soc_update_bits(codec, WM8770_OUTMUX1, 0x180, 0x180);
+		break;
+	}
+
+	return 0;
+}
+
+static int vout34supply_event(struct snd_soc_dapm_widget *w,
+	struct snd_kcontrol *kcontrol, int event)
+{
+	struct snd_soc_codec *codec;
+
+	codec = w->codec;
+
+	switch (event) {
+	case SND_SOC_DAPM_PRE_PMU:
+		snd_soc_update_bits(codec, WM8770_OUTMUX2, 0x180, 0);
+		break;
+	case SND_SOC_DAPM_POST_PMD:
+		snd_soc_update_bits(codec, WM8770_OUTMUX2, 0x180, 0x180);
+		break;
+	}
+
+	return 0;
+}
+
+static int wm8770_reset(struct snd_soc_codec *codec)
+{
+	return snd_soc_write(codec, WM8770_RESET, 0);
+}
+
+static int wm8770_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
+{
+	struct snd_soc_codec *codec;
+	int iface, master;
+
+	codec = dai->codec;
+
+	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+	case SND_SOC_DAIFMT_CBM_CFM:
+		master = 0x100;
+		break;
+	case SND_SOC_DAIFMT_CBS_CFS:
+		master = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	iface = 0;
+	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+	case SND_SOC_DAIFMT_I2S:
+		iface |= 0x2;
+		break;
+	case SND_SOC_DAIFMT_RIGHT_J:
+		break;
+	case SND_SOC_DAIFMT_LEFT_J:
+		iface |= 0x1;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+	case SND_SOC_DAIFMT_NB_NF:
+		break;
+	case SND_SOC_DAIFMT_IB_IF:
+		iface |= 0xc;
+		break;
+	case SND_SOC_DAIFMT_IB_NF:
+		iface |= 0x8;
+		break;
+	case SND_SOC_DAIFMT_NB_IF:
+		iface |= 0x4;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	snd_soc_update_bits(codec, WM8770_IFACECTRL, 0xf, iface);
+	snd_soc_update_bits(codec, WM8770_MSTRCTRL, 0x100, master);
+
+	return 0;
+}
+
+static const int mclk_ratios[] = {
+	128,
+	192,
+	256,
+	384,
+	512,
+	768
+};
+
+static int wm8770_hw_params(struct snd_pcm_substream *substream,
+			    struct snd_pcm_hw_params *params,
+			    struct snd_soc_dai *dai)
+{
+	struct snd_soc_codec *codec;
+	struct wm8770_priv *wm8770;
+	int i;
+	int iface;
+	int shift;
+	int ratio;
+
+	codec = dai->codec;
+	wm8770 = snd_soc_codec_get_drvdata(codec);
+
+	iface = 0;
+	switch (params_format(params)) {
+	case SNDRV_PCM_FORMAT_S16_LE:
+		break;
+	case SNDRV_PCM_FORMAT_S20_3LE:
+		iface |= 0x10;
+		break;
+	case SNDRV_PCM_FORMAT_S24_LE:
+		iface |= 0x20;
+		break;
+	case SNDRV_PCM_FORMAT_S32_LE:
+		iface |= 0x30;
+		break;
+	}
+
+	switch (substream->stream) {
+	case SNDRV_PCM_STREAM_PLAYBACK:
+		i = 0;
+		shift = 4;
+		break;
+	case SNDRV_PCM_STREAM_CAPTURE:
+		i = 2;
+		shift = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* Only need to set MCLK/LRCLK ratio if we're master */
+	if (snd_soc_read(codec, WM8770_MSTRCTRL) & 0x100) {
+		for (; i < ARRAY_SIZE(mclk_ratios); ++i) {
+			ratio = wm8770->sysclk / params_rate(params);
+			if (ratio == mclk_ratios[i])
+				break;
+		}
+
+		if (i == ARRAY_SIZE(mclk_ratios)) {
+			dev_err(codec->dev,
+				"Unable to configure MCLK ratio %d/%d\n",
+				wm8770->sysclk, params_rate(params));
+			return -EINVAL;
+		}
+
+		dev_dbg(codec->dev, "MCLK is %dfs\n", mclk_ratios[i]);
+
+		snd_soc_update_bits(codec, WM8770_MSTRCTRL, 0x7 << shift,
+				    i << shift);
+	}
+
+	snd_soc_update_bits(codec, WM8770_IFACECTRL, 0x30, iface);
+
+	return 0;
+}
+
+static int wm8770_mute(struct snd_soc_dai *dai, int mute)
+{
+	struct snd_soc_codec *codec;
+
+	codec = dai->codec;
+	return snd_soc_update_bits(codec, WM8770_DACMUTE, 0x10,
+				   !!mute << 4);
+}
+
+static int wm8770_set_sysclk(struct snd_soc_dai *dai,
+			     int clk_id, unsigned int freq, int dir)
+{
+	struct snd_soc_codec *codec;
+	struct wm8770_priv *wm8770;
+
+	codec = dai->codec;
+	wm8770 = snd_soc_codec_get_drvdata(codec);
+	wm8770->sysclk = freq;
+	return 0;
+}
+
+static void wm8770_sync_cache(struct snd_soc_codec *codec)
+{
+	int i;
+	u16 *cache;
+
+	if (!codec->cache_sync)
+		return;
+
+	codec->cache_only = 0;
+	cache = codec->reg_cache;
+	for (i = 0; i < codec->driver->reg_cache_size; i++) {
+		if (i == WM8770_RESET || cache[i] == wm8770_reg_defs[i])
+			continue;
+		snd_soc_write(codec, i, cache[i]);
+	}
+	codec->cache_sync = 0;
+}
+
+static int wm8770_set_bias_level(struct snd_soc_codec *codec,
+				 enum snd_soc_bias_level level)
+{
+	int ret;
+	struct wm8770_priv *wm8770;
+
+	wm8770 = snd_soc_codec_get_drvdata(codec);
+
+	switch (level) {
+	case SND_SOC_BIAS_ON:
+		break;
+	case SND_SOC_BIAS_PREPARE:
+		break;
+	case SND_SOC_BIAS_STANDBY:
+		if (codec->dapm.bias_level == SND_SOC_BIAS_OFF) {
+			ret = regulator_bulk_enable(ARRAY_SIZE(wm8770->supplies),
+						    wm8770->supplies);
+			if (ret) {
+				dev_err(codec->dev,
+					"Failed to enable supplies: %d\n",
+					ret);
+				return ret;
+			}
+			wm8770_sync_cache(codec);
+			/* global powerup */
+			snd_soc_write(codec, WM8770_PWDNCTRL, 0);
+		}
+		break;
+	case SND_SOC_BIAS_OFF:
+		/* global powerdown */
+		snd_soc_write(codec, WM8770_PWDNCTRL, 1);
+		regulator_bulk_disable(ARRAY_SIZE(wm8770->supplies),
+				       wm8770->supplies);
+		break;
+	}
+
+	codec->dapm.bias_level = level;
+	return 0;
+}
+
+#define WM8770_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE | \
+			SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
+
+static struct snd_soc_dai_ops wm8770_dai_ops = {
+	.digital_mute = wm8770_mute,
+	.hw_params = wm8770_hw_params,
+	.set_fmt = wm8770_set_fmt,
+	.set_sysclk = wm8770_set_sysclk,
+};
+
+static struct snd_soc_dai_driver wm8770_dai = {
+	.name = "wm8770-hifi",
+	.playback = {
+		.stream_name = "Playback",
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_8000_192000,
+		.formats = WM8770_FORMATS
+	},
+	.capture = {
+		.stream_name = "Capture",
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_8000_96000,
+		.formats = WM8770_FORMATS
+	},
+	.ops = &wm8770_dai_ops,
+	.symmetric_rates = 1
+};
+
+#ifdef CONFIG_PM
+static int wm8770_suspend(struct snd_soc_codec *codec, pm_message_t state)
+{
+	wm8770_set_bias_level(codec, SND_SOC_BIAS_OFF);
+	return 0;
+}
+
+static int wm8770_resume(struct snd_soc_codec *codec)
+{
+	wm8770_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
+	return 0;
+}
+#else
+#define wm8770_suspend NULL
+#define wm8770_resume NULL
+#endif
+
+static int wm8770_probe(struct snd_soc_codec *codec)
+{
+	struct wm8770_priv *wm8770;
+	int ret;
+	int i;
+
+	wm8770 = snd_soc_codec_get_drvdata(codec);
+	wm8770->codec = codec;
+
+	codec->dapm.idle_bias_off = 1;
+
+	ret = snd_soc_codec_set_cache_io(codec, 7, 9, wm8770->control_type);
+	if (ret < 0) {
+		dev_err(codec->dev, "Failed to set cache I/O: %d\n", ret);
+		return ret;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(wm8770->supplies); i++)
+		wm8770->supplies[i].supply = wm8770_supply_names[i];
+
+	ret = regulator_bulk_get(codec->dev, ARRAY_SIZE(wm8770->supplies),
+				 wm8770->supplies);
+	if (ret) {
+		dev_err(codec->dev, "Failed to request supplies: %d\n", ret);
+		return ret;
+	}
+
+	wm8770->disable_nb[0].notifier_call = wm8770_regulator_event_0;
+	wm8770->disable_nb[1].notifier_call = wm8770_regulator_event_1;
+	wm8770->disable_nb[2].notifier_call = wm8770_regulator_event_2;
+
+	/* This should really be moved into the regulator core */
+	for (i = 0; i < ARRAY_SIZE(wm8770->supplies); i++) {
+		ret = regulator_register_notifier(wm8770->supplies[i].consumer,
+						  &wm8770->disable_nb[i]);
+		if (ret) {
+			dev_err(codec->dev,
+				"Failed to register regulator notifier: %d\n",
+				ret);
+		}
+	}
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(wm8770->supplies),
+				    wm8770->supplies);
+	if (ret) {
+		dev_err(codec->dev, "Failed to enable supplies: %d\n", ret);
+		goto err_reg_get;
+	}
+
+	ret = wm8770_reset(codec);
+	if (ret < 0) {
+		dev_err(codec->dev, "Failed to issue reset: %d\n", ret);
+		goto err_reg_enable;
+	}
+
+	wm8770_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
+
+	/* latch the volume update bits */
+	snd_soc_update_bits(codec, WM8770_MSDIGVOL, 0x100, 0x100);
+	snd_soc_update_bits(codec, WM8770_MSALGVOL, 0x100, 0x100);
+	snd_soc_update_bits(codec, WM8770_VOUT1RVOL, 0x100, 0x100);
+	snd_soc_update_bits(codec, WM8770_VOUT2RVOL, 0x100, 0x100);
+	snd_soc_update_bits(codec, WM8770_VOUT3RVOL, 0x100, 0x100);
+	snd_soc_update_bits(codec, WM8770_VOUT4RVOL, 0x100, 0x100);
+	snd_soc_update_bits(codec, WM8770_DAC1RVOL, 0x100, 0x100);
+	snd_soc_update_bits(codec, WM8770_DAC2RVOL, 0x100, 0x100);
+	snd_soc_update_bits(codec, WM8770_DAC3RVOL, 0x100, 0x100);
+	snd_soc_update_bits(codec, WM8770_DAC4RVOL, 0x100, 0x100);
+
+	/* mute all DACs */
+	snd_soc_update_bits(codec, WM8770_DACMUTE, 0x10, 0x10);
+
+	snd_soc_add_controls(codec, wm8770_snd_controls,
+			     ARRAY_SIZE(wm8770_snd_controls));
+	snd_soc_dapm_new_controls(&codec->dapm, wm8770_dapm_widgets,
+				  ARRAY_SIZE(wm8770_dapm_widgets));
+	snd_soc_dapm_add_routes(&codec->dapm, wm8770_intercon,
+				ARRAY_SIZE(wm8770_intercon));
+	return 0;
+
+err_reg_enable:
+	regulator_bulk_disable(ARRAY_SIZE(wm8770->supplies), wm8770->supplies);
+err_reg_get:
+	regulator_bulk_free(ARRAY_SIZE(wm8770->supplies), wm8770->supplies);
+	return ret;
+}
+
+static int wm8770_remove(struct snd_soc_codec *codec)
+{
+	struct wm8770_priv *wm8770;
+	int i;
+
+	wm8770 = snd_soc_codec_get_drvdata(codec);
+	wm8770_set_bias_level(codec, SND_SOC_BIAS_OFF);
+
+	for (i = 0; i < ARRAY_SIZE(wm8770->supplies); ++i)
+		regulator_unregister_notifier(wm8770->supplies[i].consumer,
+					      &wm8770->disable_nb[i]);
+	regulator_bulk_free(ARRAY_SIZE(wm8770->supplies), wm8770->supplies);
+	return 0;
+}
+
+static struct snd_soc_codec_driver soc_codec_dev_wm8770 = {
+	.probe = wm8770_probe,
+	.remove = wm8770_remove,
+	.suspend = wm8770_suspend,
+	.resume = wm8770_resume,
+	.set_bias_level = wm8770_set_bias_level,
+	.reg_cache_size = ARRAY_SIZE(wm8770_reg_defs),
+	.reg_word_size = sizeof (u16),
+	.reg_cache_default = wm8770_reg_defs
+};
+
+#if defined(CONFIG_SPI_MASTER)
+static int __devinit wm8770_spi_probe(struct spi_device *spi)
+{
+	struct wm8770_priv *wm8770;
+	int ret;
+
+	wm8770 = kzalloc(sizeof(struct wm8770_priv), GFP_KERNEL);
+	if (!wm8770)
+		return -ENOMEM;
+
+	wm8770->control_type = SND_SOC_SPI;
+	spi_set_drvdata(spi, wm8770);
+
+	ret = snd_soc_register_codec(&spi->dev,
+				     &soc_codec_dev_wm8770, &wm8770_dai, 1);
+	if (ret < 0)
+		kfree(wm8770);
+	return ret;
+}
+
+static int __devexit wm8770_spi_remove(struct spi_device *spi)
+{
+	snd_soc_unregister_codec(&spi->dev);
+	kfree(spi_get_drvdata(spi));
+	return 0;
+}
+
+static struct spi_driver wm8770_spi_driver = {
+	.driver = {
+		.name = "wm8770",
+		.owner = THIS_MODULE,
+	},
+	.probe = wm8770_spi_probe,
+	.remove = __devexit_p(wm8770_spi_remove)
+};
+#endif
+
+static int __init wm8770_modinit(void)
+{
+	int ret = 0;
+
+#if defined(CONFIG_SPI_MASTER)
+	ret = spi_register_driver(&wm8770_spi_driver);
+	if (ret) {
+		printk(KERN_ERR "Failed to register wm8770 SPI driver: %d\n",
+		       ret);
+	}
+#endif
+	return ret;
+}
+module_init(wm8770_modinit);
+
+static void __exit wm8770_exit(void)
+{
+#if defined(CONFIG_SPI_MASTER)
+	spi_unregister_driver(&wm8770_spi_driver);
+#endif
+}
+module_exit(wm8770_exit);
+
+MODULE_DESCRIPTION("ASoC WM8770 driver");
+MODULE_AUTHOR("Dimitris Papastamos <[e-mail]>");
+MODULE_LICENSE("GPL");

sound/soc/codecs/wm8770.h

···
+/*
+ * wm8770.h  --  WM8770 ASoC driver
+ *
+ * Copyright 2010 Wolfson Microelectronics plc
+ *
+ * Author: Dimitris Papastamos <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _WM8770_H
+#define _WM8770_H
+
+/* Registers */
+#define WM8770_VOUT1LVOL                0
+#define WM8770_VOUT1RVOL                0x1
+#define WM8770_VOUT2LVOL                0x2
+#define WM8770_VOUT2RVOL                0x3
+#define WM8770_VOUT3LVOL                0x4
+#define WM8770_VOUT3RVOL                0x5
+#define WM8770_VOUT4LVOL                0x6
+#define WM8770_VOUT4RVOL                0x7
+#define WM8770_MSALGVOL                 0x8
+#define WM8770_DAC1LVOL                 0x9
+#define WM8770_DAC1RVOL                 0xa
+#define WM8770_DAC2LVOL                 0xb
+#define WM8770_DAC2RVOL                 0xc
+#define WM8770_DAC3LVOL                 0xd
+#define WM8770_DAC3RVOL                 0xe
+#define WM8770_DAC4LVOL                 0xf
+#define WM8770_DAC4RVOL                 0x10
+#define WM8770_MSDIGVOL                 0x11
+#define WM8770_DACPHASE                 0x12
+#define WM8770_DACCTRL1                 0x13
+#define WM8770_DACMUTE                  0x14
+#define WM8770_DACCTRL2                 0x15
+#define WM8770_IFACECTRL                0x16
+#define WM8770_MSTRCTRL                 0x17
+#define WM8770_PWDNCTRL                 0x18
+#define WM8770_ADCLCTRL                 0x19
+#define WM8770_ADCRCTRL                 0x1a
+#define WM8770_ADCMUX                   0x1b
+#define WM8770_OUTMUX1                  0x1c
+#define WM8770_OUTMUX2                  0x1d
+#define WM8770_RESET                    0x31
+
+#define WM8770_CACHEREGNUM 0x20
+
+#endif