ASoC: Add WM2000 driver

The WM2000 is a low power, high quality handset receiver speaker
driver with Wolfson myZone™ Ambient Noise Cancellation (ANC). It
provides enhanced voice communication quality in a noisy environment
if the handset acoustics are designed appropriately.

Signed-off-by: Mark Brown <[e-mail]>
Acked-by: Liam Girdwood <[e-mail]>

include/sound/wm2000.h

···
+/*
+ * linux/sound/wm2000.h -- Platform data for WM2000
+ *
+ * Copyright 2010 Wolfson Microelectronics. PLC.
+ *
+ * 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 __LINUX_SND_WM2000_H
+#define __LINUX_SND_WM2000_H
+
+struct wm2000_platform_data {
+	/** Filename for system-specific image to download to device. */
+	const char *download_file;
+
+	/** Divide MCLK by 2 for system clock? */
+	unsigned int mclkdiv2:1;
+
+	/** Disable speech clarity enhancement, for use when an
+	 * external algorithm is used. */
+	unsigned int speech_enh_disable:1;
+};
+
+#endif

sound/soc/codecs/Kconfig

···
 	select SND_SOC_TWL4030 if TWL4030_CORE
 	select SND_SOC_UDA134X
 	select SND_SOC_UDA1380 if I2C
+	select SND_SOC_WM2000 if I2C
 	select SND_SOC_WM8350 if MFD_WM8350
 	select SND_SOC_WM8400 if MFD_WM8400
 	select SND_SOC_WM8510 if SND_SOC_I2C_AND_SPI
···
 	tristate
 
 config SND_SOC_TPA6130A2
+	tristate
+
+config SND_SOC_WM2000
 	tristate

sound/soc/codecs/Makefile

···
 # Amp
 snd-soc-max9877-objs := max9877.o
 snd-soc-tpa6130a2-objs := tpa6130a2.o
+snd-soc-wm2000-objs := wm2000.o
 
 obj-$(CONFIG_SND_SOC_AC97_CODEC)	+= snd-soc-ac97.o
 obj-$(CONFIG_SND_SOC_AD1836)	+= snd-soc-ad1836.o
···
 # Amp
 obj-$(CONFIG_SND_SOC_MAX9877)	+= snd-soc-max9877.o
 obj-$(CONFIG_SND_SOC_TPA6130A2)	+= snd-soc-tpa6130a2.o
+obj-$(CONFIG_SND_SOC_WM2000)	+= snd-soc-wm2000.o

sound/soc/codecs/wm2000.c

···
+/*
+ * wm2000.c  --  WM2000 ALSA Soc Audio driver
+ *
+ * Copyright 2008-2010 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <[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.
+ *
+ * The download image for the WM2000 will be requested as
+ * 'wm2000_anc.bin' by default (overridable via platform data) at
+ * runtime and is expected to be in flat binary format.  This is
+ * generated by Wolfson configuration tools and includes
+ * system-specific callibration information.  If supplied as a
+ * sequence of ASCII-encoded hexidecimal bytes this can be converted
+ * into a flat binary with a command such as this on the command line:
+ *
+ * perl -e 'while (<>) { s/[\r\n]+// ; printf("%c", hex($_)); }'
+ *                 < file  > wm2000_anc.bin
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/firmware.h>
+#include <linux/delay.h>
+#include <linux/pm.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/debugfs.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 <sound/wm2000.h>
+
+#include "wm2000.h"
+
+enum wm2000_anc_mode {
+	ANC_ACTIVE = 0,
+	ANC_BYPASS = 1,
+	ANC_STANDBY = 2,
+	ANC_OFF = 3,
+};
+
+struct wm2000_priv {
+	struct i2c_client *i2c;
+
+	enum wm2000_anc_mode anc_mode;
+
+	unsigned int anc_active:1;
+	unsigned int anc_eng_ena:1;
+	unsigned int spk_ena:1;
+
+	unsigned int mclk_div:1;
+	unsigned int speech_clarity:1;
+
+	int anc_download_size;
+	char *anc_download;
+};
+
+static struct i2c_client *wm2000_i2c;
+
+static int wm2000_write(struct i2c_client *i2c, unsigned int reg,
+			unsigned int value)
+{
+	u8 data[3];
+	int ret;
+
+	data[0] = (reg >> 8) & 0xff;
+	data[1] = reg & 0xff;
+	data[2] = value & 0xff;
+
+	dev_vdbg(&i2c->dev, "write %x = %x\n", reg, value);
+
+	ret = i2c_master_send(i2c, data, 3);
+	if (ret == 3)
+		return 0;
+	if (ret < 0)
+		return ret;
+	else
+		return -EIO;
+}
+
+static unsigned int wm2000_read(struct i2c_client *i2c, unsigned int r)
+{
+	struct i2c_msg xfer[2];
+	u8 reg[2];
+	u8 data;
+	int ret;
+
+	/* Write register */
+	reg[0] = (r >> 8) & 0xff;
+	reg[1] = r & 0xff;
+	xfer[0].addr = i2c->addr;
+	xfer[0].flags = 0;
+	xfer[0].len = sizeof(reg);
+	xfer[0].buf = &reg[0];
+
+	/* Read data */
+	xfer[1].addr = i2c->addr;
+	xfer[1].flags = I2C_M_RD;
+	xfer[1].len = 1;
+	xfer[1].buf = &data;
+
+	ret = i2c_transfer(i2c->adapter, xfer, 2);
+	if (ret != 2) {
+		dev_err(&i2c->dev, "i2c_transfer() returned %d\n", ret);
+		return 0;
+	}
+
+	dev_vdbg(&i2c->dev, "read %x from %x\n", data, r);
+
+	return data;
+}
+
+static void wm2000_reset(struct wm2000_priv *wm2000)
+{
+	struct i2c_client *i2c = wm2000->i2c;
+
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_ENG_CLR);
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_CLR);
+	wm2000_write(i2c, WM2000_REG_ID1, 0);
+
+	wm2000->anc_mode = ANC_OFF;
+}
+
+static int wm2000_poll_bit(struct i2c_client *i2c,
+			   unsigned int reg, u8 mask, int timeout)
+{
+	int val;
+
+	val = wm2000_read(i2c, reg);
+
+	while (!(val & mask) && --timeout) {
+		msleep(1);
+		val = wm2000_read(i2c, reg);
+	}
+
+	if (timeout == 0)
+		return 0;
+	else
+		return 1;
+}
+
+static int wm2000_power_up(struct i2c_client *i2c, int analogue)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);
+	int ret, timeout;
+
+	BUG_ON(wm2000->anc_mode != ANC_OFF);
+
+	dev_dbg(&i2c->dev, "Beginning power up\n");
+
+	if (!wm2000->mclk_div) {
+		dev_dbg(&i2c->dev, "Disabling MCLK divider\n");
+		wm2000_write(i2c, WM2000_REG_SYS_CTL2,
+			     WM2000_MCLK_DIV2_ENA_CLR);
+	} else {
+		dev_dbg(&i2c->dev, "Enabling MCLK divider\n");
+		wm2000_write(i2c, WM2000_REG_SYS_CTL2,
+			     WM2000_MCLK_DIV2_ENA_SET);
+	}
+
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_ENG_CLR);
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_ENG_SET);
+
+	/* Wait for ANC engine to become ready */
+	if (!wm2000_poll_bit(i2c, WM2000_REG_ANC_STAT,
+			     WM2000_ANC_ENG_IDLE, 1)) {
+		dev_err(&i2c->dev, "ANC engine failed to reset\n");
+		return -ETIMEDOUT;
+	}
+
+	if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
+			     WM2000_STATUS_BOOT_COMPLETE, 1)) {
+		dev_err(&i2c->dev, "ANC engine failed to initialise\n");
+		return -ETIMEDOUT;
+	}
+
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_SET);
+
+	/* Open code download of the data since it is the only bulk
+	 * write we do. */
+	dev_dbg(&i2c->dev, "Downloading %d bytes\n",
+		wm2000->anc_download_size - 2);
+
+	ret = i2c_master_send(i2c, wm2000->anc_download,
+			      wm2000->anc_download_size);
+	if (ret < 0) {
+		dev_err(&i2c->dev, "i2c_transfer() failed: %d\n", ret);
+		return ret;
+	}
+	if (ret != wm2000->anc_download_size) {
+		dev_err(&i2c->dev, "i2c_transfer() failed, %d != %d\n",
+			ret, wm2000->anc_download_size);
+		return -EIO;
+	}
+
+	dev_dbg(&i2c->dev, "Download complete\n");
+
+	if (analogue) {
+		timeout = 248;
+		wm2000_write(i2c, WM2000_REG_ANA_VMID_PU_TIME, timeout / 4);
+
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_ANA_SEQ_INCLUDE |
+			     WM2000_MODE_MOUSE_ENABLE |
+			     WM2000_MODE_THERMAL_ENABLE);
+	} else {
+		timeout = 10;
+
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_MOUSE_ENABLE |
+			     WM2000_MODE_THERMAL_ENABLE);
+	}
+
+	ret = wm2000_read(i2c, WM2000_REG_SPEECH_CLARITY);
+	if (wm2000->speech_clarity)
+		ret &= ~WM2000_SPEECH_CLARITY;
+	else
+		ret |= WM2000_SPEECH_CLARITY;
+	wm2000_write(i2c, WM2000_REG_SPEECH_CLARITY, ret);
+
+	wm2000_write(i2c, WM2000_REG_SYS_START0, 0x33);
+	wm2000_write(i2c, WM2000_REG_SYS_START1, 0x02);
+
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_INT_N_CLR);
+
+	if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
+			     WM2000_STATUS_MOUSE_ACTIVE, timeout)) {
+		dev_err(&i2c->dev, "Timed out waiting for device after %dms\n",
+			timeout * 10);
+		return -ETIMEDOUT;
+	}
+
+	dev_dbg(&i2c->dev, "ANC active\n");
+	if (analogue)
+		dev_dbg(&i2c->dev, "Analogue active\n");
+	wm2000->anc_mode = ANC_ACTIVE;
+
+	return 0;
+}
+
+static int wm2000_power_down(struct i2c_client *i2c, int analogue)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);
+	int timeout;
+
+	if (analogue) {
+		timeout = 248;
+		wm2000_write(i2c, WM2000_REG_ANA_VMID_PD_TIME, timeout / 4);
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_ANA_SEQ_INCLUDE |
+			     WM2000_MODE_POWER_DOWN);
+	} else {
+		timeout = 10;
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_POWER_DOWN);
+	}
+
+	if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
+			     WM2000_STATUS_POWER_DOWN_COMPLETE, timeout)) {
+		dev_err(&i2c->dev, "Timeout waiting for ANC power down\n");
+		return -ETIMEDOUT;
+	}
+
+	if (!wm2000_poll_bit(i2c, WM2000_REG_ANC_STAT,
+			     WM2000_ANC_ENG_IDLE, 1)) {
+		dev_err(&i2c->dev, "Timeout waiting for ANC engine idle\n");
+		return -ETIMEDOUT;
+	}
+
+	dev_dbg(&i2c->dev, "powered off\n");
+	wm2000->anc_mode = ANC_OFF;
+
+	return 0;
+}
+
+static int wm2000_enter_bypass(struct i2c_client *i2c, int analogue)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);
+
+	BUG_ON(wm2000->anc_mode != ANC_ACTIVE);
+
+	if (analogue) {
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_ANA_SEQ_INCLUDE |
+			     WM2000_MODE_THERMAL_ENABLE |
+			     WM2000_MODE_BYPASS_ENTRY);
+	} else {
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_THERMAL_ENABLE |
+			     WM2000_MODE_BYPASS_ENTRY);
+	}
+
+	if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
+			     WM2000_STATUS_ANC_DISABLED, 10)) {
+		dev_err(&i2c->dev, "Timeout waiting for ANC disable\n");
+		return -ETIMEDOUT;
+	}
+
+	if (!wm2000_poll_bit(i2c, WM2000_REG_ANC_STAT,
+			     WM2000_ANC_ENG_IDLE, 1)) {
+		dev_err(&i2c->dev, "Timeout waiting for ANC engine idle\n");
+		return -ETIMEDOUT;
+	}
+
+	wm2000_write(i2c, WM2000_REG_SYS_CTL1, WM2000_SYS_STBY);
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_CLR);
+
+	wm2000->anc_mode = ANC_BYPASS;
+	dev_dbg(&i2c->dev, "bypass enabled\n");
+
+	return 0;
+}
+
+static int wm2000_exit_bypass(struct i2c_client *i2c, int analogue)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);
+
+	BUG_ON(wm2000->anc_mode != ANC_BYPASS);
+	
+	wm2000_write(i2c, WM2000_REG_SYS_CTL1, 0);
+
+	if (analogue) {
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_ANA_SEQ_INCLUDE |
+			     WM2000_MODE_MOUSE_ENABLE |
+			     WM2000_MODE_THERMAL_ENABLE);
+	} else {
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_MOUSE_ENABLE |
+			     WM2000_MODE_THERMAL_ENABLE);
+	}
+
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_SET);
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_INT_N_CLR);
+
+	if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
+			     WM2000_STATUS_MOUSE_ACTIVE, 10)) {
+		dev_err(&i2c->dev, "Timed out waiting for MOUSE\n");
+		return -ETIMEDOUT;
+	}
+
+	wm2000->anc_mode = ANC_ACTIVE;
+	dev_dbg(&i2c->dev, "MOUSE active\n");
+
+	return 0;
+}
+
+static int wm2000_enter_standby(struct i2c_client *i2c, int analogue)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);
+	int timeout;
+
+	BUG_ON(wm2000->anc_mode != ANC_ACTIVE);
+
+	if (analogue) {
+		timeout = 248;
+		wm2000_write(i2c, WM2000_REG_ANA_VMID_PD_TIME, timeout / 4);
+
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_ANA_SEQ_INCLUDE |
+			     WM2000_MODE_THERMAL_ENABLE |
+			     WM2000_MODE_STANDBY_ENTRY);
+	} else {
+		timeout = 10;
+
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_THERMAL_ENABLE |
+			     WM2000_MODE_STANDBY_ENTRY);
+	}
+
+	if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
+			     WM2000_STATUS_ANC_DISABLED, timeout)) {
+		dev_err(&i2c->dev,
+			"Timed out waiting for ANC disable after 1ms\n");
+		return -ETIMEDOUT;
+	}
+
+	if (!wm2000_poll_bit(i2c, WM2000_REG_ANC_STAT, WM2000_ANC_ENG_IDLE,
+			     1)) {
+		dev_err(&i2c->dev,
+			"Timed out waiting for standby after %dms\n",
+			timeout * 10);
+		return -ETIMEDOUT;
+	}
+
+	wm2000_write(i2c, WM2000_REG_SYS_CTL1, WM2000_SYS_STBY);
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_CLR);
+
+	wm2000->anc_mode = ANC_STANDBY;
+	dev_dbg(&i2c->dev, "standby\n");
+	if (analogue)
+		dev_dbg(&i2c->dev, "Analogue disabled\n");
+
+	return 0;
+}
+
+static int wm2000_exit_standby(struct i2c_client *i2c, int analogue)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);
+	int timeout;
+
+	BUG_ON(wm2000->anc_mode != ANC_STANDBY);
+
+	wm2000_write(i2c, WM2000_REG_SYS_CTL1, 0);
+
+	if (analogue) {
+		timeout = 248;
+		wm2000_write(i2c, WM2000_REG_ANA_VMID_PU_TIME, timeout / 4);
+
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_ANA_SEQ_INCLUDE |
+			     WM2000_MODE_THERMAL_ENABLE |
+			     WM2000_MODE_MOUSE_ENABLE);
+	} else {
+		timeout = 10;
+
+		wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
+			     WM2000_MODE_THERMAL_ENABLE |
+			     WM2000_MODE_MOUSE_ENABLE);
+	}
+
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_SET);
+	wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_INT_N_CLR);
+
+	if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
+			     WM2000_STATUS_MOUSE_ACTIVE, timeout)) {
+		dev_err(&i2c->dev, "Timed out waiting for MOUSE after %dms\n",
+			timeout * 10);
+		return -ETIMEDOUT;
+	}
+
+	wm2000->anc_mode = ANC_ACTIVE;
+	dev_dbg(&i2c->dev, "MOUSE active\n");
+	if (analogue)
+		dev_dbg(&i2c->dev, "Analogue enabled\n");
+
+	return 0;
+}
+
+typedef int (*wm2000_mode_fn)(struct i2c_client *i2c, int analogue);
+
+static struct {
+	enum wm2000_anc_mode source;
+	enum wm2000_anc_mode dest;
+	int analogue;
+	wm2000_mode_fn step[2];
+} anc_transitions[] = {
+	{
+		.source = ANC_OFF,
+		.dest = ANC_ACTIVE,
+		.analogue = 1,
+		.step = {
+			wm2000_power_up,
+		},
+	},
+	{
+		.source = ANC_OFF,
+		.dest = ANC_STANDBY,
+		.step = {
+			wm2000_power_up,
+			wm2000_enter_standby,
+		},
+	},
+	{
+		.source = ANC_OFF,
+		.dest = ANC_BYPASS,
+		.analogue = 1,
+		.step = {
+			wm2000_power_up,
+			wm2000_enter_bypass,
+		},
+	},
+	{
+		.source = ANC_ACTIVE,
+		.dest = ANC_BYPASS,
+		.analogue = 1,
+		.step = {
+			wm2000_enter_bypass,
+		},
+	},
+	{
+		.source = ANC_ACTIVE,
+		.dest = ANC_STANDBY,
+		.analogue = 1,
+		.step = {
+			wm2000_enter_standby,
+		},
+	},
+	{
+		.source = ANC_ACTIVE,
+		.dest = ANC_OFF,
+		.analogue = 1,
+		.step = {
+			wm2000_power_down,
+		},
+	},
+	{
+		.source = ANC_BYPASS,
+		.dest = ANC_ACTIVE,
+		.analogue = 1,
+		.step = {
+			wm2000_exit_bypass,
+		},
+	},
+	{
+		.source = ANC_BYPASS,
+		.dest = ANC_STANDBY,
+		.analogue = 1,
+		.step = {
+			wm2000_exit_bypass,
+			wm2000_enter_standby,
+		},
+	},
+	{
+		.source = ANC_BYPASS,
+		.dest = ANC_OFF,
+		.step = {
+			wm2000_exit_bypass,
+			wm2000_power_down,
+		},
+	},
+	{
+		.source = ANC_STANDBY,
+		.dest = ANC_ACTIVE,
+		.analogue = 1,
+		.step = {
+			wm2000_exit_standby,
+		},
+	},
+	{
+		.source = ANC_STANDBY,
+		.dest = ANC_BYPASS,
+		.analogue = 1,
+		.step = {
+			wm2000_exit_standby,
+			wm2000_enter_bypass,
+		},
+	},
+	{
+		.source = ANC_STANDBY,
+		.dest = ANC_OFF,
+		.step = {
+			wm2000_exit_standby,
+			wm2000_power_down,
+		},
+	},
+};
+
+static int wm2000_anc_transition(struct wm2000_priv *wm2000,
+				 enum wm2000_anc_mode mode)
+{
+	struct i2c_client *i2c = wm2000->i2c;
+	int i, j;
+	int ret;
+
+	if (wm2000->anc_mode == mode)
+		return 0;
+
+	for (i = 0; i < ARRAY_SIZE(anc_transitions); i++)
+		if (anc_transitions[i].source == wm2000->anc_mode &&
+		    anc_transitions[i].dest == mode)
+			break;
+	if (i == ARRAY_SIZE(anc_transitions)) {
+		dev_err(&i2c->dev, "No transition for %d->%d\n",
+			wm2000->anc_mode, mode);
+		return -EINVAL;
+	}
+
+	for (j = 0; j < ARRAY_SIZE(anc_transitions[j].step); j++) {
+		if (!anc_transitions[i].step[j])
+			break;
+		ret = anc_transitions[i].step[j](i2c,
+						 anc_transitions[i].analogue);
+		if (ret != 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int wm2000_anc_set_mode(struct wm2000_priv *wm2000)
+{
+	struct i2c_client *i2c = wm2000->i2c;
+	enum wm2000_anc_mode mode;
+
+	if (wm2000->anc_eng_ena && wm2000->spk_ena)
+		if (wm2000->anc_active)
+			mode = ANC_ACTIVE;
+		else
+			mode = ANC_BYPASS;
+	else
+		mode = ANC_STANDBY;
+
+	dev_dbg(&i2c->dev, "Set mode %d (enabled %d, mute %d, active %d)\n",
+		mode, wm2000->anc_eng_ena, !wm2000->spk_ena,
+		wm2000->anc_active);
+
+	return wm2000_anc_transition(wm2000, mode);
+}
+
+static int wm2000_anc_mode_get(struct snd_kcontrol *kcontrol,
+			       struct snd_ctl_elem_value *ucontrol)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&wm2000_i2c->dev);
+
+	ucontrol->value.enumerated.item[0] = wm2000->anc_active;
+
+	return 0;
+}
+
+static int wm2000_anc_mode_put(struct snd_kcontrol *kcontrol,
+			       struct snd_ctl_elem_value *ucontrol)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&wm2000_i2c->dev);
+	int anc_active = ucontrol->value.enumerated.item[0];
+
+	if (anc_active > 1)
+		return -EINVAL;
+
+	wm2000->anc_active = anc_active;
+
+	return wm2000_anc_set_mode(wm2000);
+}
+
+static int wm2000_speaker_get(struct snd_kcontrol *kcontrol,
+			      struct snd_ctl_elem_value *ucontrol)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&wm2000_i2c->dev);
+
+	ucontrol->value.enumerated.item[0] = wm2000->spk_ena;
+
+	return 0;
+}
+
+static int wm2000_speaker_put(struct snd_kcontrol *kcontrol,
+			      struct snd_ctl_elem_value *ucontrol)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&wm2000_i2c->dev);
+	int val = ucontrol->value.enumerated.item[0];
+
+	if (val > 1)
+		return -EINVAL;
+
+	wm2000->spk_ena = val;
+
+	return wm2000_anc_set_mode(wm2000);
+}
+
+static const struct snd_kcontrol_new wm2000_controls[] = {
+	SOC_SINGLE_BOOL_EXT("WM2000 ANC Switch", 0,
+			    wm2000_anc_mode_get,
+			    wm2000_anc_mode_put),
+	SOC_SINGLE_BOOL_EXT("WM2000 Switch", 0,
+			    wm2000_speaker_get,
+			    wm2000_speaker_put),
+};
+
+static int wm2000_anc_power_event(struct snd_soc_dapm_widget *w,
+				  struct snd_kcontrol *kcontrol, int event)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&wm2000_i2c->dev);
+
+	if (SND_SOC_DAPM_EVENT_ON(event))
+		wm2000->anc_eng_ena = 1;
+
+	if (SND_SOC_DAPM_EVENT_OFF(event))
+		wm2000->anc_eng_ena = 0;
+
+	return wm2000_anc_set_mode(wm2000);
+}
+
+static const struct snd_soc_dapm_widget wm2000_dapm_widgets[] = {
+/* Externally visible pins */
+SND_SOC_DAPM_OUTPUT("WM2000 SPKN"),
+SND_SOC_DAPM_OUTPUT("WM2000 SPKP"),
+
+SND_SOC_DAPM_INPUT("WM2000 LINN"),
+SND_SOC_DAPM_INPUT("WM2000 LINP"),
+
+SND_SOC_DAPM_PGA_E("ANC Engine", SND_SOC_NOPM, 0, 0, NULL, 0,
+		   wm2000_anc_power_event,
+		   SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
+};
+
+/* Target, Path, Source */
+static const struct snd_soc_dapm_route audio_map[] = {
+	{ "WM2000 SPKN", NULL, "ANC Engine" },
+	{ "WM2000 SPKP", NULL, "ANC Engine" },
+	{ "ANC Engine", NULL, "WM2000 LINN" },
+	{ "ANC Engine", NULL, "WM2000 LINP" },
+};
+
+/* Called from the machine driver */
+int wm2000_add_controls(struct snd_soc_codec *codec)
+{
+	int ret;
+
+	if (!wm2000_i2c) {
+		pr_err("WM2000 not yet probed\n");
+		return -ENODEV;
+	}
+
+	ret = snd_soc_dapm_new_controls(codec, wm2000_dapm_widgets,
+					ARRAY_SIZE(wm2000_dapm_widgets));
+	if (ret < 0)
+		return ret;
+
+	ret = snd_soc_dapm_add_routes(codec, audio_map, ARRAY_SIZE(audio_map));
+	if (ret < 0)
+		return ret;
+
+	return snd_soc_add_controls(codec, wm2000_controls,
+			ARRAY_SIZE(wm2000_controls));
+}
+EXPORT_SYMBOL_GPL(wm2000_add_controls);
+
+static int __devinit wm2000_i2c_probe(struct i2c_client *i2c,
+				      const struct i2c_device_id *i2c_id)
+{
+	struct wm2000_priv *wm2000;
+	struct wm2000_platform_data *pdata;
+	const char *filename;
+	const struct firmware *fw;
+	int reg, ret;
+	u16 id;
+
+	if (wm2000_i2c) {
+		dev_err(&i2c->dev, "Another WM2000 is already registered\n");
+		return -EINVAL;
+	}
+
+	wm2000 = kzalloc(sizeof(struct wm2000_priv), GFP_KERNEL);
+	if (wm2000 == NULL) {
+		dev_err(&i2c->dev, "Unable to allocate private data\n");
+		return -ENOMEM;
+	}
+
+	/* Verify that this is a WM2000 */
+	reg = wm2000_read(i2c, WM2000_REG_ID1);
+	id = reg << 8;
+	reg = wm2000_read(i2c, WM2000_REG_ID2);
+	id |= reg & 0xff;
+
+	if (id != 0x2000) {
+		dev_err(&i2c->dev, "Device is not a WM2000 - ID %x\n", id);
+		ret = -ENODEV;
+		goto err;
+	}
+
+	reg = wm2000_read(i2c, WM2000_REG_REVISON);
+	dev_info(&i2c->dev, "revision %c\n", reg + 'A');
+
+	filename = "wm2000_anc.bin";
+	pdata = dev_get_platdata(&i2c->dev);
+	if (pdata) {
+		wm2000->mclk_div = pdata->mclkdiv2;
+		wm2000->speech_clarity = !pdata->speech_enh_disable;
+
+		if (pdata->download_file)
+			filename = pdata->download_file;
+	}
+
+	ret = request_firmware(&fw, filename, &i2c->dev);
+	if (ret != 0) {
+		dev_err(&i2c->dev, "Failed to acquire ANC data: %d\n", ret);
+		goto err;
+	}
+
+	/* Pre-cook the concatenation of the register address onto the image */
+	wm2000->anc_download_size = fw->size + 2;
+	wm2000->anc_download = kmalloc(wm2000->anc_download_size, GFP_KERNEL);
+	if (wm2000->anc_download == NULL) {
+		dev_err(&i2c->dev, "Out of memory\n");
+		ret = -ENOMEM;
+		goto err_fw;
+	}
+
+	wm2000->anc_download[0] = 0x80;
+	wm2000->anc_download[1] = 0x00;
+	memcpy(wm2000->anc_download + 2, fw->data, fw->size);
+
+	release_firmware(fw);
+
+	dev_set_drvdata(&i2c->dev, wm2000);
+	wm2000->anc_eng_ena = 1;
+	wm2000->i2c = i2c;
+
+	wm2000_reset(wm2000);
+
+	/* This will trigger a transition to standby mode by default */
+	wm2000_anc_set_mode(wm2000);	
+
+	wm2000_i2c = i2c;
+
+	return 0;
+
+err_fw:
+	release_firmware(fw);
+err:
+	kfree(wm2000);
+	return ret;
+}
+
+static __devexit int wm2000_i2c_remove(struct i2c_client *i2c)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);
+
+	wm2000_anc_transition(wm2000, ANC_OFF);
+
+	wm2000_i2c = NULL;
+	kfree(wm2000->anc_download);
+	kfree(wm2000);
+
+	return 0;
+}
+
+static void wm2000_i2c_shutdown(struct i2c_client *i2c)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);
+
+	wm2000_anc_transition(wm2000, ANC_OFF);
+}
+
+#ifdef CONFIG_PM
+static int wm2000_i2c_suspend(struct i2c_client *i2c, pm_message_t mesg)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);
+
+	return wm2000_anc_transition(wm2000, ANC_OFF);
+}
+
+static int wm2000_i2c_resume(struct i2c_client *i2c)
+{
+	struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);
+
+	return wm2000_anc_set_mode(wm2000);
+}
+#else
+#define wm2000_i2c_suspend NULL
+#define wm2000_i2c_resume NULL
+#endif
+
+static const struct i2c_device_id wm2000_i2c_id[] = {
+	{ "wm2000", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, wm2000_i2c_id);
+
+static struct i2c_driver wm2000_i2c_driver = {
+	.driver = {
+		.name = "wm2000",
+		.owner = THIS_MODULE,
+	},
+	.probe = wm2000_i2c_probe,
+	.remove = __devexit_p(wm2000_i2c_remove),
+	.suspend = wm2000_i2c_suspend,
+	.resume = wm2000_i2c_resume,
+	.shutdown = wm2000_i2c_shutdown,
+	.id_table = wm2000_i2c_id,
+};
+
+static int __init wm2000_init(void)
+{
+	return i2c_add_driver(&wm2000_i2c_driver);
+}
+module_init(wm2000_init);
+
+static void __exit wm2000_exit(void)
+{
+	i2c_del_driver(&wm2000_i2c_driver);
+}
+module_exit(wm2000_exit);
+
+MODULE_DESCRIPTION("ASoC WM2000 driver");
+MODULE_AUTHOR("Mark Brown <[e-mail]>");
+MODULE_LICENSE("GPL");

sound/soc/codecs/wm2000.h

···
+/*
+ * wm2000.h  --  WM2000 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 _WM2000_H
+#define _WM2000_H
+
+struct wm2000_setup_data {
+	unsigned short i2c_address;
+	int mclk_div;   /* Set to a non-zero value if MCLK_DIV_2 required */
+};
+
+extern int wm2000_add_controls(struct snd_soc_codec *codec);
+
+extern struct snd_soc_dai wm2000_dai;
+extern struct snd_soc_codec_device soc_codec_dev_wm2000;
+
+#define WM2000_REG_SYS_START	    0x8000
+#define WM2000_REG_SPEECH_CLARITY   0x8fef
+#define WM2000_REG_SYS_WATCHDOG     0x8ff6
+#define WM2000_REG_ANA_VMID_PD_TIME 0x8ff7
+#define WM2000_REG_ANA_VMID_PU_TIME 0x8ff8
+#define WM2000_REG_CAT_FLTR_INDX    0x8ff9
+#define WM2000_REG_CAT_GAIN_0       0x8ffa
+#define WM2000_REG_SYS_STATUS       0x8ffc
+#define WM2000_REG_SYS_MODE_CNTRL   0x8ffd
+#define WM2000_REG_SYS_START0       0x8ffe
+#define WM2000_REG_SYS_START1       0x8fff
+#define WM2000_REG_ID1              0xf000
+#define WM2000_REG_ID2              0xf001
+#define WM2000_REG_REVISON          0xf002
+#define WM2000_REG_SYS_CTL1         0xf003
+#define WM2000_REG_SYS_CTL2         0xf004
+#define WM2000_REG_ANC_STAT         0xf005
+#define WM2000_REG_IF_CTL           0xf006
+
+/* SPEECH_CLARITY */
+#define WM2000_SPEECH_CLARITY   0x01
+
+/* SYS_STATUS */
+#define WM2000_STATUS_MOUSE_ACTIVE              0x40
+#define WM2000_STATUS_CAT_FREQ_COMPLETE         0x20
+#define WM2000_STATUS_CAT_GAIN_COMPLETE         0x10
+#define WM2000_STATUS_THERMAL_SHUTDOWN_COMPLETE 0x08
+#define WM2000_STATUS_ANC_DISABLED              0x04
+#define WM2000_STATUS_POWER_DOWN_COMPLETE       0x02
+#define WM2000_STATUS_BOOT_COMPLETE             0x01
+
+/* SYS_MODE_CNTRL */
+#define WM2000_MODE_ANA_SEQ_INCLUDE 0x80
+#define WM2000_MODE_MOUSE_ENABLE    0x40
+#define WM2000_MODE_CAT_FREQ_ENABLE 0x20
+#define WM2000_MODE_CAT_GAIN_ENABLE 0x10
+#define WM2000_MODE_BYPASS_ENTRY    0x08
+#define WM2000_MODE_STANDBY_ENTRY   0x04
+#define WM2000_MODE_THERMAL_ENABLE  0x02
+#define WM2000_MODE_POWER_DOWN      0x01
+
+/* SYS_CTL1 */
+#define WM2000_SYS_STBY          0x01
+
+/* SYS_CTL2 */
+#define WM2000_MCLK_DIV2_ENA_CLR 0x80
+#define WM2000_MCLK_DIV2_ENA_SET 0x40
+#define WM2000_ANC_ENG_CLR       0x20
+#define WM2000_ANC_ENG_SET       0x10
+#define WM2000_ANC_INT_N_CLR     0x08
+#define WM2000_ANC_INT_N_SET     0x04
+#define WM2000_RAM_CLR           0x02
+#define WM2000_RAM_SET           0x01
+
+/* ANC_STAT */
+#define WM2000_ANC_ENG_IDLE      0x01
+
+#endif