ASoC WM8940 Driver

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

4 files changed, 1065 insertions, 0 deletions

diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 121d63f13dbb..1c19ad54a9f9 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -35,6 +35,7 @@ config SND_SOC_ALL_CODECS
         select SND_SOC_WM8753 if SND_SOC_I2C_AND_SPI
         select SND_SOC_WM8900 if I2C
         select SND_SOC_WM8903 if I2C
+        select SND_SOC_WM8940 if I2C
         select SND_SOC_WM8960 if I2C
         select SND_SOC_WM8971 if I2C
         select SND_SOC_WM8988 if SND_SOC_I2C_AND_SPI
@@ -140,6 +141,9 @@ config SND_SOC_WM8900
 config SND_SOC_WM8903
         tristate
 
+config SND_SOC_WM8940
+        tristate
+
 config SND_SOC_WM8960
         tristate
 
diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile
index 811696861d31..3d31b6bea834 100644
--- a/sound/soc/codecs/Makefile
+++ b/sound/soc/codecs/Makefile
@@ -23,6 +23,7 @@ snd-soc-wm8750-objs := wm8750.o
 snd-soc-wm8753-objs := wm8753.o
 snd-soc-wm8900-objs := wm8900.o
 snd-soc-wm8903-objs := wm8903.o
+snd-soc-wm8940-objs := wm8940.o
 snd-soc-wm8960-objs := wm8960.o
 snd-soc-wm8971-objs := wm8971.o
 snd-soc-wm8988-objs := wm8988.o
@@ -57,6 +58,7 @@ obj-$(CONFIG_SND_SOC_WM8753)	+= snd-soc-wm8753.o
 obj-$(CONFIG_SND_SOC_WM8900)    += snd-soc-wm8900.o
 obj-$(CONFIG_SND_SOC_WM8903)    += snd-soc-wm8903.o
 obj-$(CONFIG_SND_SOC_WM8971)    += snd-soc-wm8971.o
+obj-$(CONFIG_SND_SOC_WM8940)    += snd-soc-wm8940.o
 obj-$(CONFIG_SND_SOC_WM8960)    += snd-soc-wm8960.o
 obj-$(CONFIG_SND_SOC_WM8988)    += snd-soc-wm8988.o
 obj-$(CONFIG_SND_SOC_WM8990)    += snd-soc-wm8990.o
diff --git a/sound/soc/codecs/wm8940.c b/sound/soc/codecs/wm8940.c
new file mode 100644
index 000000000000..26987dcd8d55
--- /dev/null
+++ b/sound/soc/codecs/wm8940.c
@@ -0,0 +1,955 @@
+/*
+ * wm8940.c  --  WM8940 ALSA Soc Audio driver
+ *
+ * Author: Jonathan Cameron <jic23@cam.ac.uk>
+ *
+ * Based on wm8510.c
+ *    Copyright  2006 Wolfson Microelectronics PLC.
+ *    Author:  Liam Girdwood <lrg@slimlogic.co.uk>
+ *
+ * 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.
+ *
+ * Not currently handled:
+ * Notch filter control
+ * AUXMode (inverting vs mixer)
+ * No means to obtain current gain if alc enabled.
+ * No use made of gpio
+ * Fast VMID discharge for power down
+ * Soft Start
+ * DLR and ALR Swaps not enabled
+ * Digital Sidetone not supported
+ */
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/pm.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.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 "wm8940.h"
+
+struct wm8940_priv {
+        unsigned int sysclk;
+        u16 reg_cache[WM8940_CACHEREGNUM];
+        struct snd_soc_codec codec;
+};
+
+static u16 wm8940_reg_defaults[] = {
+        0x8940, /* Soft Reset */
+        0x0000, /* Power 1 */
+        0x0000, /* Power 2 */
+        0x0000, /* Power 3 */
+        0x0010, /* Interface Control */
+        0x0000, /* Companding Control */
+        0x0140, /* Clock Control */
+        0x0000, /* Additional Controls */
+        0x0000, /* GPIO Control */
+        0x0002, /* Auto Increment Control */
+        0x0000, /* DAC Control */
+        0x00FF, /* DAC Volume */
+        0,
+        0,
+        0x0100, /* ADC Control */
+        0x00FF, /* ADC Volume */
+        0x0000, /* Notch Filter 1 Control 1 */
+        0x0000, /* Notch Filter 1 Control 2 */
+        0x0000, /* Notch Filter 2 Control 1 */
+        0x0000, /* Notch Filter 2 Control 2 */
+        0x0000, /* Notch Filter 3 Control 1 */
+        0x0000, /* Notch Filter 3 Control 2 */
+        0x0000, /* Notch Filter 4 Control 1 */
+        0x0000, /* Notch Filter 4 Control 2 */
+        0x0032, /* DAC Limit Control 1 */
+        0x0000, /* DAC Limit Control 2 */
+        0,
+        0,
+        0,
+        0,
+        0,
+        0,
+        0x0038, /* ALC Control 1 */
+        0x000B, /* ALC Control 2 */
+        0x0032, /* ALC Control 3 */
+        0x0000, /* Noise Gate */
+        0x0041, /* PLLN */
+        0x000C, /* PLLK1 */
+        0x0093, /* PLLK2 */
+        0x00E9, /* PLLK3 */
+        0,
+        0,
+        0x0030, /* ALC Control 4 */
+        0,
+        0x0002, /* Input Control */
+        0x0050, /* PGA Gain */
+        0,
+        0x0002, /* ADC Boost Control */
+        0,
+        0x0002, /* Output Control */
+        0x0000, /* Speaker Mixer Control */
+        0,
+        0,
+        0,
+        0x0079, /* Speaker Volume */
+        0,
+        0x0000, /* Mono Mixer Control */
+};
+
+static inline unsigned int wm8940_read_reg_cache(struct snd_soc_codec *codec,
+                                                 unsigned int reg)
+{
+        u16 *cache = codec->reg_cache;
+
+        if (reg >= ARRAY_SIZE(wm8940_reg_defaults))
+                return -1;
+
+        return cache[reg];
+}
+
+static inline int wm8940_write_reg_cache(struct snd_soc_codec *codec,
+                                          u16 reg, unsigned int value)
+{
+        u16 *cache = codec->reg_cache;
+
+        if (reg >= ARRAY_SIZE(wm8940_reg_defaults))
+                return -1;
+
+        cache[reg] = value;
+
+        return 0;
+}
+
+static int wm8940_write(struct snd_soc_codec *codec, unsigned int reg,
+                        unsigned int value)
+{
+        int ret;
+        u8 data[3] = { reg,
+                       (value & 0xff00) >> 8,
+                       (value & 0x00ff)
+        };
+
+        wm8940_write_reg_cache(codec, reg, value);
+
+        ret = codec->hw_write(codec->control_data, data, 3);
+
+        if (ret < 0)
+                return ret;
+        else if (ret != 3)
+                return -EIO;
+        return 0;
+}
+
+static const char *wm8940_companding[] = { "Off", "NC", "u-law", "A-law" };
+static const struct soc_enum wm8940_adc_companding_enum
+= SOC_ENUM_SINGLE(WM8940_COMPANDINGCTL, 1, 4, wm8940_companding);
+static const struct soc_enum wm8940_dac_companding_enum
+= SOC_ENUM_SINGLE(WM8940_COMPANDINGCTL, 3, 4, wm8940_companding);
+
+static const char *wm8940_alc_mode_text[] = {"ALC", "Limiter"};
+static const struct soc_enum wm8940_alc_mode_enum
+= SOC_ENUM_SINGLE(WM8940_ALC3, 8, 2, wm8940_alc_mode_text);
+
+static const char *wm8940_mic_bias_level_text[] = {"0.9", "0.65"};
+static const struct soc_enum wm8940_mic_bias_level_enum
+= SOC_ENUM_SINGLE(WM8940_INPUTCTL, 8, 2, wm8940_mic_bias_level_text);
+
+static const char *wm8940_filter_mode_text[] = {"Audio", "Application"};
+static const struct soc_enum wm8940_filter_mode_enum
+= SOC_ENUM_SINGLE(WM8940_ADC, 7, 2, wm8940_filter_mode_text);
+
+DECLARE_TLV_DB_SCALE(wm8940_spk_vol_tlv, -5700, 100, 1);
+DECLARE_TLV_DB_SCALE(wm8940_att_tlv, -1000, 1000, 0);
+DECLARE_TLV_DB_SCALE(wm8940_pga_vol_tlv, -1200, 75, 0);
+DECLARE_TLV_DB_SCALE(wm8940_alc_min_tlv, -1200, 600, 0);
+DECLARE_TLV_DB_SCALE(wm8940_alc_max_tlv, 675, 600, 0);
+DECLARE_TLV_DB_SCALE(wm8940_alc_tar_tlv, -2250, 50, 0);
+DECLARE_TLV_DB_SCALE(wm8940_lim_boost_tlv, 0, 100, 0);
+DECLARE_TLV_DB_SCALE(wm8940_lim_thresh_tlv, -600, 100, 0);
+DECLARE_TLV_DB_SCALE(wm8940_adc_tlv, -12750, 50, 1);
+DECLARE_TLV_DB_SCALE(wm8940_capture_boost_vol_tlv, 0, 2000, 0);
+
+static const struct snd_kcontrol_new wm8940_snd_controls[] = {
+        SOC_SINGLE("Digital Loopback Switch", WM8940_COMPANDINGCTL,
+                   6, 1, 0),
+        SOC_ENUM("DAC Companding", wm8940_dac_companding_enum),
+        SOC_ENUM("ADC Companding", wm8940_adc_companding_enum),
+
+        SOC_ENUM("ALC Mode", wm8940_alc_mode_enum),
+        SOC_SINGLE("ALC Switch", WM8940_ALC1, 8, 1, 0),
+        SOC_SINGLE_TLV("ALC Capture Max Gain", WM8940_ALC1,
+                       3, 7, 1, wm8940_alc_max_tlv),
+        SOC_SINGLE_TLV("ALC Capture Min Gain", WM8940_ALC1,
+                       0, 7, 0, wm8940_alc_min_tlv),
+        SOC_SINGLE_TLV("ALC Capture Target", WM8940_ALC2,
+                       0, 14, 0, wm8940_alc_tar_tlv),
+        SOC_SINGLE("ALC Capture Hold", WM8940_ALC2, 4, 10, 0),
+        SOC_SINGLE("ALC Capture Decay", WM8940_ALC3, 4, 10, 0),
+        SOC_SINGLE("ALC Capture Attach", WM8940_ALC3, 0, 10, 0),
+        SOC_SINGLE("ALC ZC Switch", WM8940_ALC4, 1, 1, 0),
+        SOC_SINGLE("ALC Capture Noise Gate Switch", WM8940_NOISEGATE,
+                   3, 1, 0),
+        SOC_SINGLE("ALC Capture Noise Gate Threshold", WM8940_NOISEGATE,
+                   0, 7, 0),
+
+        SOC_SINGLE("DAC Playback Limiter Switch", WM8940_DACLIM1, 8, 1, 0),
+        SOC_SINGLE("DAC Playback Limiter Attack", WM8940_DACLIM1, 0, 9, 0),
+        SOC_SINGLE("DAC Playback Limiter Decay", WM8940_DACLIM1, 4, 11, 0),
+        SOC_SINGLE_TLV("DAC Playback Limiter Threshold", WM8940_DACLIM2,
+                       4, 9, 1, wm8940_lim_thresh_tlv),
+        SOC_SINGLE_TLV("DAC Playback Limiter Boost", WM8940_DACLIM2,
+                       0, 12, 0, wm8940_lim_boost_tlv),
+
+        SOC_SINGLE("Capture PGA ZC Switch", WM8940_PGAGAIN, 7, 1, 0),
+        SOC_SINGLE_TLV("Capture PGA Volume", WM8940_PGAGAIN,
+                       0, 63, 0, wm8940_pga_vol_tlv),
+        SOC_SINGLE_TLV("Digital Playback Volume", WM8940_DACVOL,
+                       0, 255, 0, wm8940_adc_tlv),
+        SOC_SINGLE_TLV("Digital Capture Volume", WM8940_ADCVOL,
+                       0, 255, 0, wm8940_adc_tlv),
+        SOC_ENUM("Mic Bias Level", wm8940_mic_bias_level_enum),
+        SOC_SINGLE_TLV("Capture Boost Volue", WM8940_ADCBOOST,
+                       8, 1, 0, wm8940_capture_boost_vol_tlv),
+        SOC_SINGLE_TLV("Speaker Playback Volume", WM8940_SPKVOL,
+                       0, 63, 0, wm8940_spk_vol_tlv),
+        SOC_SINGLE("Speaker Playback Switch", WM8940_SPKVOL,  6, 1, 1),
+
+        SOC_SINGLE_TLV("Speaker Mixer Line Bypass Volume", WM8940_SPKVOL,
+                       8, 1, 1, wm8940_att_tlv),
+        SOC_SINGLE("Speaker Playback ZC Switch", WM8940_SPKVOL, 7, 1, 0),
+
+        SOC_SINGLE("Mono Out Switch", WM8940_MONOMIX, 6, 1, 1),
+        SOC_SINGLE_TLV("Mono Mixer Line Bypass Volume", WM8940_MONOMIX,
+                       7, 1, 1, wm8940_att_tlv),
+
+        SOC_SINGLE("High Pass Filter Switch", WM8940_ADC, 8, 1, 0),
+        SOC_ENUM("High Pass Filter Mode", wm8940_filter_mode_enum),
+        SOC_SINGLE("High Pass Filter Cut Off", WM8940_ADC, 4, 7, 0),
+        SOC_SINGLE("ADC Inversion Switch", WM8940_ADC, 0, 1, 0),
+        SOC_SINGLE("DAC Inversion Switch", WM8940_DAC, 0, 1, 0),
+        SOC_SINGLE("DAC Auto Mute Switch", WM8940_DAC, 2, 1, 0),
+        SOC_SINGLE("ZC Timeout Clock Switch", WM8940_ADDCNTRL, 0, 1, 0),
+};
+
+static const struct snd_kcontrol_new wm8940_speaker_mixer_controls[] = {
+        SOC_DAPM_SINGLE("Line Bypass Switch", WM8940_SPKMIX, 1, 1, 0),
+        SOC_DAPM_SINGLE("Aux Playback Switch", WM8940_SPKMIX, 5, 1, 0),
+        SOC_DAPM_SINGLE("PCM Playback Switch", WM8940_SPKMIX, 0, 1, 0),
+};
+
+static const struct snd_kcontrol_new wm8940_mono_mixer_controls[] = {
+        SOC_DAPM_SINGLE("Line Bypass Switch", WM8940_MONOMIX, 1, 1, 0),
+        SOC_DAPM_SINGLE("Aux Playback Switch", WM8940_MONOMIX, 2, 1, 0),
+        SOC_DAPM_SINGLE("PCM Playback Switch", WM8940_MONOMIX, 0, 1, 0),
+};
+
+DECLARE_TLV_DB_SCALE(wm8940_boost_vol_tlv, -1500, 300, 1);
+static const struct snd_kcontrol_new wm8940_input_boost_controls[] = {
+        SOC_DAPM_SINGLE("Mic PGA Switch", WM8940_PGAGAIN, 6, 1, 1),
+        SOC_DAPM_SINGLE_TLV("Aux Volume", WM8940_ADCBOOST,
+                            0, 7, 0, wm8940_boost_vol_tlv),
+        SOC_DAPM_SINGLE_TLV("Mic Volume", WM8940_ADCBOOST,
+                            4, 7, 0, wm8940_boost_vol_tlv),
+};
+
+static const struct snd_kcontrol_new wm8940_micpga_controls[] = {
+        SOC_DAPM_SINGLE("AUX Switch", WM8940_INPUTCTL, 2, 1, 0),
+        SOC_DAPM_SINGLE("MICP Switch", WM8940_INPUTCTL, 0, 1, 0),
+        SOC_DAPM_SINGLE("MICN Switch", WM8940_INPUTCTL, 1, 1, 0),
+};
+
+static const struct snd_soc_dapm_widget wm8940_dapm_widgets[] = {
+        SND_SOC_DAPM_MIXER("Speaker Mixer", WM8940_POWER3, 2, 0,
+                           &wm8940_speaker_mixer_controls[0],
+                           ARRAY_SIZE(wm8940_speaker_mixer_controls)),
+        SND_SOC_DAPM_MIXER("Mono Mixer", WM8940_POWER3, 3, 0,
+                           &wm8940_mono_mixer_controls[0],
+                           ARRAY_SIZE(wm8940_mono_mixer_controls)),
+        SND_SOC_DAPM_DAC("DAC", "HiFi Playback", WM8940_POWER3, 0, 0),
+
+        SND_SOC_DAPM_PGA("SpkN Out", WM8940_POWER3, 5, 0, NULL, 0),
+        SND_SOC_DAPM_PGA("SpkP Out", WM8940_POWER3, 6, 0, NULL, 0),
+        SND_SOC_DAPM_PGA("Mono Out", WM8940_POWER3, 7, 0, NULL, 0),
+        SND_SOC_DAPM_OUTPUT("MONOOUT"),
+        SND_SOC_DAPM_OUTPUT("SPKOUTP"),
+        SND_SOC_DAPM_OUTPUT("SPKOUTN"),
+
+        SND_SOC_DAPM_PGA("Aux Input", WM8940_POWER1, 6, 0, NULL, 0),
+        SND_SOC_DAPM_ADC("ADC", "HiFi Capture", WM8940_POWER2, 0, 0),
+        SND_SOC_DAPM_MIXER("Mic PGA", WM8940_POWER2, 2, 0,
+                           &wm8940_micpga_controls[0],
+                           ARRAY_SIZE(wm8940_micpga_controls)),
+        SND_SOC_DAPM_MIXER("Boost Mixer", WM8940_POWER2, 4, 0,
+                           &wm8940_input_boost_controls[0],
+                           ARRAY_SIZE(wm8940_input_boost_controls)),
+        SND_SOC_DAPM_MICBIAS("Mic Bias", WM8940_POWER1, 4, 0),
+
+        SND_SOC_DAPM_INPUT("MICN"),
+        SND_SOC_DAPM_INPUT("MICP"),
+        SND_SOC_DAPM_INPUT("AUX"),
+};
+
+static const struct snd_soc_dapm_route audio_map[] = {
+        /* Mono output mixer */
+        {"Mono Mixer", "PCM Playback Switch", "DAC"},
+        {"Mono Mixer", "Aux Playback Switch", "Aux Input"},
+        {"Mono Mixer", "Line Bypass Switch", "Boost Mixer"},
+
+        /* Speaker output mixer */
+        {"Speaker Mixer", "PCM Playback Switch", "DAC"},
+        {"Speaker Mixer", "Aux Playback Switch", "Aux Input"},
+        {"Speaker Mixer", "Line Bypass Switch", "Boost Mixer"},
+
+        /* Outputs */
+        {"Mono Out", NULL, "Mono Mixer"},
+        {"MONOOUT", NULL, "Mono Out"},
+        {"SpkN Out", NULL, "Speaker Mixer"},
+        {"SpkP Out", NULL, "Speaker Mixer"},
+        {"SPKOUTN", NULL, "SpkN Out"},
+        {"SPKOUTP", NULL, "SpkP Out"},
+
+        /*  Microphone PGA */
+        {"Mic PGA", "MICN Switch", "MICN"},
+        {"Mic PGA", "MICP Switch", "MICP"},
+        {"Mic PGA", "AUX Switch", "AUX"},
+
+        /* Boost Mixer */
+        {"Boost Mixer", "Mic PGA Switch", "Mic PGA"},
+        {"Boost Mixer", "Mic Volume",  "MICP"},
+        {"Boost Mixer", "Aux Volume", "Aux Input"},
+
+        {"ADC", NULL, "Boost Mixer"},
+};
+
+static int wm8940_add_widgets(struct snd_soc_codec *codec)
+{
+        int ret;
+
+        ret = snd_soc_dapm_new_controls(codec, wm8940_dapm_widgets,
+                                        ARRAY_SIZE(wm8940_dapm_widgets));
+        if (ret)
+                goto error_ret;
+        ret = snd_soc_dapm_add_routes(codec, audio_map, ARRAY_SIZE(audio_map));
+        if (ret)
+                goto error_ret;
+        ret = snd_soc_dapm_new_widgets(codec);
+
+error_ret:
+        return ret;
+}
+
+#define wm8940_reset(c) wm8940_write(c, WM8940_SOFTRESET, 0);
+
+static int wm8940_set_dai_fmt(struct snd_soc_dai *codec_dai,
+                              unsigned int fmt)
+{
+        struct snd_soc_codec *codec = codec_dai->codec;
+        u16 iface = wm8940_read_reg_cache(codec, WM8940_IFACE) & 0xFE67;
+        u16 clk = wm8940_read_reg_cache(codec, WM8940_CLOCK) & 0x1fe;
+
+        switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+        case SND_SOC_DAIFMT_CBM_CFM:
+                clk |= 1;
+                break;
+        case SND_SOC_DAIFMT_CBS_CFS:
+                break;
+        default:
+                return -EINVAL;
+        }
+        wm8940_write(codec, WM8940_CLOCK, clk);
+
+        switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+        case SND_SOC_DAIFMT_I2S:
+                iface |= (2 << 3);
+                break;
+        case SND_SOC_DAIFMT_LEFT_J:
+                iface |= (1 << 3);
+                break;
+        case SND_SOC_DAIFMT_RIGHT_J:
+                break;
+        case SND_SOC_DAIFMT_DSP_A:
+                iface |= (3 << 3);
+                break;
+        case SND_SOC_DAIFMT_DSP_B:
+                iface |= (3 << 3) | (1 << 7);
+                break;
+        }
+
+        switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+        case SND_SOC_DAIFMT_NB_NF:
+                break;
+        case SND_SOC_DAIFMT_NB_IF:
+                iface |= (1 << 7);
+                break;
+        case SND_SOC_DAIFMT_IB_NF:
+                iface |= (1 << 8);
+                break;
+        case SND_SOC_DAIFMT_IB_IF:
+                iface |= (1 << 8) | (1 << 7);
+                break;
+        }
+
+        wm8940_write(codec, WM8940_IFACE, iface);
+
+        return 0;
+}
+
+static int wm8940_i2s_hw_params(struct snd_pcm_substream *substream,
+                                struct snd_pcm_hw_params *params,
+                                struct snd_soc_dai *dai)
+{
+        struct snd_soc_pcm_runtime *rtd = substream->private_data;
+        struct snd_soc_device *socdev = rtd->socdev;
+        struct snd_soc_codec *codec = socdev->card->codec;
+        u16 iface = wm8940_read_reg_cache(codec, WM8940_IFACE) & 0xFD9F;
+        u16 addcntrl = wm8940_read_reg_cache(codec, WM8940_ADDCNTRL) & 0xFFF1;
+        u16 companding =  wm8940_read_reg_cache(codec,
+                                                WM8940_COMPANDINGCTL) & 0xFFDF;
+        int ret;
+
+        /* LoutR control */
+        if (substream->stream == SNDRV_PCM_STREAM_CAPTURE
+            && params_channels(params) == 2)
+                iface |= (1 << 9);
+
+        switch (params_rate(params)) {
+        case SNDRV_PCM_RATE_8000:
+                addcntrl |= (0x5 << 1);
+                break;
+        case SNDRV_PCM_RATE_11025:
+                addcntrl |= (0x4 << 1);
+                break;
+        case SNDRV_PCM_RATE_16000:
+                addcntrl |= (0x3 << 1);
+                break;
+        case SNDRV_PCM_RATE_22050:
+                addcntrl |= (0x2 << 1);
+                break;
+        case SNDRV_PCM_RATE_32000:
+                addcntrl |= (0x1 << 1);
+                break;
+        case SNDRV_PCM_RATE_44100:
+        case SNDRV_PCM_RATE_48000:
+                break;
+        }
+        ret = wm8940_write(codec, WM8940_ADDCNTRL, addcntrl);
+        if (ret)
+                goto error_ret;
+
+        switch (params_format(params)) {
+        case SNDRV_PCM_FORMAT_S8:
+                companding = companding | (1 << 5);
+                break;
+        case SNDRV_PCM_FORMAT_S16_LE:
+                break;
+        case SNDRV_PCM_FORMAT_S20_3LE:
+                iface |= (1 << 5);
+                break;
+        case SNDRV_PCM_FORMAT_S24_LE:
+                iface |= (2 << 5);
+                break;
+        case SNDRV_PCM_FORMAT_S32_LE:
+                iface |= (3 << 5);
+                break;
+        }
+        ret = wm8940_write(codec, WM8940_COMPANDINGCTL, companding);
+        if (ret)
+                goto error_ret;
+        ret = wm8940_write(codec, WM8940_IFACE, iface);
+
+error_ret:
+        return ret;
+}
+
+static int wm8940_mute(struct snd_soc_dai *dai, int mute)
+{
+        struct snd_soc_codec *codec = dai->codec;
+        u16 mute_reg = wm8940_read_reg_cache(codec, WM8940_DAC) & 0xffbf;
+
+        if (mute)
+                mute_reg |= 0x40;
+
+        return wm8940_write(codec, WM8940_DAC, mute_reg);
+}
+
+static int wm8940_set_bias_level(struct snd_soc_codec *codec,
+                                 enum snd_soc_bias_level level)
+{
+        u16 val;
+        u16 pwr_reg = wm8940_read_reg_cache(codec, WM8940_POWER1) & 0x1F0;
+        int ret = 0;
+
+        switch (level) {
+        case SND_SOC_BIAS_ON:
+                /* ensure bufioen and biasen */
+                pwr_reg |= (1 << 2) | (1 << 3);
+                /* Enable thermal shutdown */
+                val = wm8940_read_reg_cache(codec, WM8940_OUTPUTCTL);
+                ret = wm8940_write(codec, WM8940_OUTPUTCTL, val | 0x2);
+                if (ret)
+                        break;
+                /* set vmid to 75k */
+                ret = wm8940_write(codec, WM8940_POWER1, pwr_reg | 0x1);
+                break;
+        case SND_SOC_BIAS_PREPARE:
+                /* ensure bufioen and biasen */
+                pwr_reg |= (1 << 2) | (1 << 3);
+                ret = wm8940_write(codec, WM8940_POWER1, pwr_reg | 0x1);
+                break;
+        case SND_SOC_BIAS_STANDBY:
+                /* ensure bufioen and biasen */
+                pwr_reg |= (1 << 2) | (1 << 3);
+                /* set vmid to 300k for standby */
+                ret = wm8940_write(codec, WM8940_POWER1, pwr_reg | 0x2);
+                break;
+        case SND_SOC_BIAS_OFF:
+                ret = wm8940_write(codec, WM8940_POWER1, pwr_reg);
+                break;
+        }
+
+        return ret;
+}
+
+struct pll_ {
+        unsigned int pre_scale:2;
+        unsigned int n:4;
+        unsigned int k;
+};
+
+static struct pll_ pll_div;
+
+/* The size in bits of the pll divide multiplied by 10
+ * to allow rounding later */
+#define FIXED_PLL_SIZE ((1 << 24) * 10)
+static void pll_factors(unsigned int target, unsigned int source)
+{
+        unsigned long long Kpart;
+        unsigned int K, Ndiv, Nmod;
+        /* The left shift ist to avoid accuracy loss when right shifting */
+        Ndiv = target / source;
+
+        if (Ndiv > 12) {
+                source <<= 1;
+                /* Multiply by 2 */
+                pll_div.pre_scale = 0;
+                Ndiv = target / source;
+        } else if (Ndiv < 3) {
+                source >>= 2;
+                /* Divide by 4 */
+                pll_div.pre_scale = 3;
+                Ndiv = target / source;
+        } else if (Ndiv < 6) {
+                source >>= 1;
+                /* divide by 2 */
+                pll_div.pre_scale = 2;
+                Ndiv = target / source;
+        } else
+                pll_div.pre_scale = 1;
+
+        if ((Ndiv < 6) || (Ndiv > 12))
+                printk(KERN_WARNING
+                        "WM8940 N value %d outwith recommended range!d\n",
+                        Ndiv);
+
+        pll_div.n = Ndiv;
+        Nmod = target % source;
+        Kpart = FIXED_PLL_SIZE * (long long)Nmod;
+
+        do_div(Kpart, source);
+
+        K = Kpart & 0xFFFFFFFF;
+
+        /* Check if we need to round */
+        if ((K % 10) >= 5)
+                K += 5;
+
+        /* Move down to proper range now rounding is done */
+        K /= 10;
+
+        pll_div.k = K;
+}
+
+/* Untested at the moment */
+static int wm8940_set_dai_pll(struct snd_soc_dai *codec_dai,
+                int pll_id, unsigned int freq_in, unsigned int freq_out)
+{
+        struct snd_soc_codec *codec = codec_dai->codec;
+        u16 reg;
+
+        /* Turn off PLL */
+        reg = wm8940_read_reg_cache(codec, WM8940_POWER1);
+        wm8940_write(codec, WM8940_POWER1, reg & 0x1df);
+
+        if (freq_in == 0 || freq_out == 0) {
+                /* Clock CODEC directly from MCLK */
+                reg = wm8940_read_reg_cache(codec, WM8940_CLOCK);
+                wm8940_write(codec, WM8940_CLOCK, reg & 0x0ff);
+                /* Pll power down */
+                wm8940_write(codec, WM8940_PLLN, (1 << 7));
+                return 0;
+        }
+
+        /* Pll is followed by a frequency divide by 4 */
+        pll_factors(freq_out*4, freq_in);
+        if (pll_div.k)
+                wm8940_write(codec, WM8940_PLLN,
+                             (pll_div.pre_scale << 4) | pll_div.n | (1 << 6));
+        else /* No factional component */
+                wm8940_write(codec, WM8940_PLLN,
+                             (pll_div.pre_scale << 4) | pll_div.n);
+        wm8940_write(codec, WM8940_PLLK1, pll_div.k >> 18);
+        wm8940_write(codec, WM8940_PLLK2, (pll_div.k >> 9) & 0x1ff);
+        wm8940_write(codec, WM8940_PLLK3, pll_div.k & 0x1ff);
+        /* Enable the PLL */
+        reg = wm8940_read_reg_cache(codec, WM8940_POWER1);
+        wm8940_write(codec, WM8940_POWER1, reg | 0x020);
+
+        /* Run CODEC from PLL instead of MCLK */
+        reg = wm8940_read_reg_cache(codec, WM8940_CLOCK);
+        wm8940_write(codec, WM8940_CLOCK, reg | 0x100);
+
+        return 0;
+}
+
+static int wm8940_set_dai_sysclk(struct snd_soc_dai *codec_dai,
+                                 int clk_id, unsigned int freq, int dir)
+{
+        struct snd_soc_codec *codec = codec_dai->codec;
+        struct wm8940_priv *wm8940 = codec->private_data;
+
+        switch (freq) {
+        case 11289600:
+        case 12000000:
+        case 12288000:
+        case 16934400:
+        case 18432000:
+                wm8940->sysclk = freq;
+                return 0;
+        }
+        return -EINVAL;
+}
+
+static int wm8940_set_dai_clkdiv(struct snd_soc_dai *codec_dai,
+                                 int div_id, int div)
+{
+        struct snd_soc_codec *codec = codec_dai->codec;
+        u16 reg;
+        int ret = 0;
+
+        switch (div_id) {
+        case WM8940_BCLKDIV:
+                reg = wm8940_read_reg_cache(codec, WM8940_CLOCK) & 0xFFEF3;
+                ret = wm8940_write(codec, WM8940_CLOCK, reg | (div << 2));
+                break;
+        case WM8940_MCLKDIV:
+                reg = wm8940_read_reg_cache(codec, WM8940_CLOCK) & 0xFF1F;
+                ret = wm8940_write(codec, WM8940_CLOCK, reg | (div << 5));
+                break;
+        case WM8940_OPCLKDIV:
+                reg = wm8940_read_reg_cache(codec, WM8940_ADDCNTRL) & 0xFFCF;
+                ret = wm8940_write(codec, WM8940_ADDCNTRL, reg | (div << 4));
+                break;
+        }
+        return ret;
+}
+
+#define WM8940_RATES SNDRV_PCM_RATE_8000_48000
+
+#define WM8940_FORMATS (SNDRV_PCM_FMTBIT_S8 |                           \
+                        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 wm8940_dai_ops = {
+        .hw_params = wm8940_i2s_hw_params,
+        .set_sysclk = wm8940_set_dai_sysclk,
+        .digital_mute = wm8940_mute,
+        .set_fmt = wm8940_set_dai_fmt,
+        .set_clkdiv = wm8940_set_dai_clkdiv,
+        .set_pll = wm8940_set_dai_pll,
+};
+
+struct snd_soc_dai wm8940_dai = {
+        .name = "WM8940",
+        .playback = {
+                .stream_name = "Playback",
+                .channels_min = 1,
+                .channels_max = 2,
+                .rates = WM8940_RATES,
+                .formats = WM8940_FORMATS,
+        },
+        .capture = {
+                .stream_name = "Capture",
+                .channels_min = 1,
+                .channels_max = 2,
+                .rates = WM8940_RATES,
+                .formats = WM8940_FORMATS,
+        },
+        .ops = &wm8940_dai_ops,
+        .symmetric_rates = 1,
+};
+EXPORT_SYMBOL_GPL(wm8940_dai);
+
+static int wm8940_suspend(struct platform_device *pdev, pm_message_t state)
+{
+        struct snd_soc_device *socdev = platform_get_drvdata(pdev);
+        struct snd_soc_codec *codec = socdev->card->codec;
+
+        return wm8940_set_bias_level(codec, SND_SOC_BIAS_OFF);
+}
+
+static int wm8940_resume(struct platform_device *pdev)
+{
+        struct snd_soc_device *socdev = platform_get_drvdata(pdev);
+        struct snd_soc_codec *codec = socdev->card->codec;
+        int i;
+        int ret;
+        u8 data[3];
+        u16 *cache = codec->reg_cache;
+
+        /* Sync reg_cache with the hardware
+         * Could use auto incremented writes to speed this up
+         */
+        for (i = 0; i < ARRAY_SIZE(wm8940_reg_defaults); i++) {
+                data[0] = i;
+                data[1] = (cache[i] & 0xFF00) >> 8;
+                data[2] = cache[i] & 0x00FF;
+                ret = codec->hw_write(codec->control_data, data, 3);
+                if (ret < 0)
+                        goto error_ret;
+                else if (ret != 3) {
+                        ret = -EIO;
+                        goto error_ret;
+                }
+        }
+        ret = wm8940_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
+        if (ret)
+                goto error_ret;
+        ret = wm8940_set_bias_level(codec, codec->suspend_bias_level);
+
+error_ret:
+        return ret;
+}
+
+static struct snd_soc_codec *wm8940_codec;
+
+static int wm8940_probe(struct platform_device *pdev)
+{
+        struct snd_soc_device *socdev = platform_get_drvdata(pdev);
+        struct snd_soc_codec *codec;
+
+        int ret = 0;
+
+        if (wm8940_codec == NULL) {
+                dev_err(&pdev->dev, "Codec device not registered\n");
+                return -ENODEV;
+        }
+
+        socdev->card->codec = wm8940_codec;
+        codec = wm8940_codec;
+
+        mutex_init(&codec->mutex);
+        /* register pcms */
+        ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
+        if (ret < 0) {
+                dev_err(codec->dev, "failed to create pcms: %d\n", ret);
+                goto pcm_err;
+        }
+
+        ret = snd_soc_add_controls(codec, wm8940_snd_controls,
+                             ARRAY_SIZE(wm8940_snd_controls));
+        if (ret)
+                goto error_free_pcms;
+        ret = wm8940_add_widgets(codec);
+        if (ret)
+                goto error_free_pcms;
+
+        ret = snd_soc_init_card(socdev);
+        if (ret < 0) {
+                dev_err(codec->dev, "failed to register card: %d\n", ret);
+                goto error_free_pcms;
+        }
+
+        return ret;
+
+error_free_pcms:
+        snd_soc_free_pcms(socdev);
+        snd_soc_dapm_free(socdev);
+pcm_err:
+        return ret;
+}
+
+static int wm8940_remove(struct platform_device *pdev)
+{
+        struct snd_soc_device *socdev = platform_get_drvdata(pdev);
+
+        snd_soc_free_pcms(socdev);
+        snd_soc_dapm_free(socdev);
+
+        return 0;
+}
+
+struct snd_soc_codec_device soc_codec_dev_wm8940 = {
+        .probe = wm8940_probe,
+        .remove = wm8940_remove,
+        .suspend = wm8940_suspend,
+        .resume = wm8940_resume,
+};
+EXPORT_SYMBOL_GPL(soc_codec_dev_wm8940);
+
+static int wm8940_register(struct wm8940_priv *wm8940)
+{
+        struct wm8940_setup_data *pdata = wm8940->codec.dev->platform_data;
+        struct snd_soc_codec *codec = &wm8940->codec;
+        int ret;
+        u16 reg;
+        if (wm8940_codec) {
+                dev_err(codec->dev, "Another WM8940 is registered\n");
+                return -EINVAL;
+        }
+
+        INIT_LIST_HEAD(&codec->dapm_widgets);
+        INIT_LIST_HEAD(&codec->dapm_paths);
+
+        codec->private_data = wm8940;
+        codec->name = "WM8940";
+        codec->owner = THIS_MODULE;
+        codec->read = wm8940_read_reg_cache;
+        codec->write = wm8940_write;
+        codec->bias_level = SND_SOC_BIAS_OFF;
+        codec->set_bias_level = wm8940_set_bias_level;
+        codec->dai = &wm8940_dai;
+        codec->num_dai = 1;
+        codec->reg_cache_size = ARRAY_SIZE(wm8940_reg_defaults);
+        codec->reg_cache = &wm8940->reg_cache;
+
+        memcpy(codec->reg_cache, wm8940_reg_defaults,
+               sizeof(wm8940_reg_defaults));
+
+        ret = wm8940_reset(codec);
+        if (ret < 0) {
+                dev_err(codec->dev, "Failed to issue reset\n");
+                return ret;
+        }
+
+        wm8940_dai.dev = codec->dev;
+
+        wm8940_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
+
+        ret = wm8940_write(codec, WM8940_POWER1, 0x180);
+        if (ret < 0)
+                return ret;
+
+        if (!pdata)
+                dev_warn(codec->dev, "No platform data supplied\n");
+        else {
+                reg = wm8940_read_reg_cache(codec, WM8940_OUTPUTCTL);
+                ret = wm8940_write(codec, WM8940_OUTPUTCTL, reg | pdata->vroi);
+                if (ret < 0)
+                        return ret;
+        }
+
+
+        wm8940_codec = codec;
+
+        ret = snd_soc_register_codec(codec);
+        if (ret) {
+                dev_err(codec->dev, "Failed to register codec: %d\n", ret);
+                return ret;
+        }
+
+        ret = snd_soc_register_dai(&wm8940_dai);
+        if (ret) {
+                dev_err(codec->dev, "Failed to register DAI: %d\n", ret);
+                snd_soc_unregister_codec(codec);
+                return ret;
+        }
+
+        return 0;
+}
+
+static void wm8940_unregister(struct wm8940_priv *wm8940)
+{
+        wm8940_set_bias_level(&wm8940->codec, SND_SOC_BIAS_OFF);
+        snd_soc_unregister_dai(&wm8940_dai);
+        snd_soc_unregister_codec(&wm8940->codec);
+        kfree(wm8940);
+        wm8940_codec = NULL;
+}
+
+static int wm8940_i2c_probe(struct i2c_client *i2c,
+                            const struct i2c_device_id *id)
+{
+        struct wm8940_priv *wm8940;
+        struct snd_soc_codec *codec;
+
+        wm8940 = kzalloc(sizeof *wm8940, GFP_KERNEL);
+        if (wm8940 == NULL)
+                return -ENOMEM;
+
+        codec = &wm8940->codec;
+        codec->hw_write = (hw_write_t)i2c_master_send;
+        i2c_set_clientdata(i2c, wm8940);
+        codec->control_data = i2c;
+        codec->dev = &i2c->dev;
+
+        return wm8940_register(wm8940);
+}
+
+static int wm8940_i2c_remove(struct i2c_client *client)
+{
+        struct wm8940_priv *wm8940 = i2c_get_clientdata(client);
+
+        wm8940_unregister(wm8940);
+
+        return 0;
+}
+
+static const struct i2c_device_id wm8940_i2c_id[] = {
+        { "wm8940", 0 },
+        { }
+};
+MODULE_DEVICE_TABLE(i2c, wm8940_i2c_id);
+
+static struct i2c_driver wm8940_i2c_driver = {
+        .driver = {
+                .name = "WM8940 I2C Codec",
+                .owner = THIS_MODULE,
+        },
+        .probe = wm8940_i2c_probe,
+        .remove = __devexit_p(wm8940_i2c_remove),
+        .id_table = wm8940_i2c_id,
+};
+
+static int __init wm8940_modinit(void)
+{
+        int ret;
+
+        ret = i2c_add_driver(&wm8940_i2c_driver);
+        if (ret)
+                printk(KERN_ERR "Failed to register WM8940 I2C driver: %d\n",
+                       ret);
+        return ret;
+}
+module_init(wm8940_modinit);
+
+static void __exit wm8940_exit(void)
+{
+        i2c_del_driver(&wm8940_i2c_driver);
+}
+module_exit(wm8940_exit);
+
+MODULE_DESCRIPTION("ASoC WM8940 driver");
+MODULE_AUTHOR("Jonathan Cameron");
+MODULE_LICENSE("GPL");
diff --git a/sound/soc/codecs/wm8940.h b/sound/soc/codecs/wm8940.h
new file mode 100644
index 000000000000..8410eed3ef84
--- /dev/null
+++ b/sound/soc/codecs/wm8940.h
@@ -0,0 +1,104 @@
+/*
+ * wm8940.h -- WM8940 Soc Audio driver
+ *
+ * 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 _WM8940_H
+#define _WM8940_H
+
+struct wm8940_setup_data {
+        /* Vref to analogue output resistance */
+#define WM8940_VROI_1K 0
+#define WM8940_VROI_30K 1
+        unsigned int vroi:1;
+};
+extern struct snd_soc_dai wm8940_dai;
+extern struct snd_soc_codec_device soc_codec_dev_wm8940;
+
+/* WM8940 register space */
+#define WM8940_SOFTRESET        0x00
+#define WM8940_POWER1           0x01
+#define WM8940_POWER2           0x02
+#define WM8940_POWER3           0x03
+#define WM8940_IFACE            0x04
+#define WM8940_COMPANDINGCTL    0x05
+#define WM8940_CLOCK            0x06
+#define WM8940_ADDCNTRL         0x07
+#define WM8940_GPIO             0x08
+#define WM8940_CTLINT           0x09
+#define WM8940_DAC              0x0A
+#define WM8940_DACVOL           0x0B
+
+#define WM8940_ADC              0x0E
+#define WM8940_ADCVOL           0x0F
+#define WM8940_NOTCH1           0x10
+#define WM8940_NOTCH2           0x11
+#define WM8940_NOTCH3           0x12
+#define WM8940_NOTCH4           0x13
+#define WM8940_NOTCH5           0x14
+#define WM8940_NOTCH6           0x15
+#define WM8940_NOTCH7           0x16
+#define WM8940_NOTCH8           0x17
+#define WM8940_DACLIM1          0x18
+#define WM8940_DACLIM2          0x19
+
+#define WM8940_ALC1             0x20
+#define WM8940_ALC2             0x21
+#define WM8940_ALC3             0x22
+#define WM8940_NOISEGATE        0x23
+#define WM8940_PLLN             0x24
+#define WM8940_PLLK1            0x25
+#define WM8940_PLLK2            0x26
+#define WM8940_PLLK3            0x27
+
+#define WM8940_ALC4             0x2A
+
+#define WM8940_INPUTCTL         0x2C
+#define WM8940_PGAGAIN          0x2D
+
+#define WM8940_ADCBOOST         0x2F
+
+#define WM8940_OUTPUTCTL        0x31
+#define WM8940_SPKMIX           0x32
+
+#define WM8940_SPKVOL           0x36
+
+#define WM8940_MONOMIX          0x38
+
+#define WM8940_CACHEREGNUM  0x57
+
+
+/* Clock divider Id's */
+#define WM8940_BCLKDIV 0
+#define WM8940_MCLKDIV 1
+#define WM8940_OPCLKDIV 2
+
+/* MCLK clock dividers */
+#define WM8940_MCLKDIV_1        0
+#define WM8940_MCLKDIV_1_5      1
+#define WM8940_MCLKDIV_2        2
+#define WM8940_MCLKDIV_3        3
+#define WM8940_MCLKDIV_4        4
+#define WM8940_MCLKDIV_6        5
+#define WM8940_MCLKDIV_8        6
+#define WM8940_MCLKDIV_12       7
+
+/* BCLK clock dividers */
+#define WM8940_BCLKDIV_1 0
+#define WM8940_BCLKDIV_2 1
+#define WM8940_BCLKDIV_4 2
+#define WM8940_BCLKDIV_8 3
+#define WM8940_BCLKDIV_16 4
+#define WM8940_BCLKDIV_32 5
+
+/* PLL Out Dividers */
+#define WM8940_OPCLKDIV_1 0
+#define WM8940_OPCLKDIV_2 1
+#define WM8940_OPCLKDIV_3 2
+#define WM8940_OPCLKDIV_4 3
+
+#endif /* _WM8940_H */
+