ASoC: TPA6130A2 amplifier driver

Driver for Texas Instruments TPA6130A2 stereo headphone
amplifier.

The driver provides playback gain control and also pre-defined
DAPM_HP widgets and DAPM routings for power management.

The DAPM_HP widget names are:
"TPA6130A2 Headphone Left"
"TPA6130A2 Headphone Right"

From soc machine drivers to use with the tpa6130a2 amplifier,
the tpa6130a2_add_controls has to be called, which adds the alsa
controls and the DAPM routing needed for the tpa6130a2.
After that the machine driver can connect the codec's output
with 'TPA6130A2 Left' and 'TPA6130A2 Right':

        {"TPA6130A2 Left", NULL, "CODEC LEFT OUT"},
        {"TPA6130A2 Right", NULL, "CODEC RIGHT OUT"},

Internally the left and right channels are powered separately.
When none of the channels are needed the amplifier is powered
down:
hard power: valid GPIO number is passed within platform data
soft power: Using the software shutdown of the amplifier

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 463 insertions, 0 deletions

diff --git a/sound/soc/codecs/tpa6130a2.c b/sound/soc/codecs/tpa6130a2.c
new file mode 100644
index 00000000000..1b77c959e2d
--- /dev/null
+++ b/sound/soc/codecs/tpa6130a2.c
@@ -0,0 +1,463 @@
+/*
+ * ALSA SoC Texas Instruments TPA6130A2 headset stereo amplifier driver
+ *
+ * Copyright (C) Nokia Corporation
+ *
+ * Author: Peter Ujfalusi <peter.ujfalusi@nokia.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+#include <sound/tpa6130a2-plat.h>
+#include <sound/soc.h>
+#include <sound/soc-dapm.h>
+#include <sound/tlv.h>
+
+#include "tpa6130a2.h"
+
+struct i2c_client *tpa6130a2_client;
+
+/* This struct is used to save the context */
+struct tpa6130a2_data {
+	struct mutex mutex;
+	unsigned char regs[TPA6130A2_CACHEREGNUM];
+	int power_gpio;
+	unsigned char power_state;
+};
+
+static int tpa6130a2_i2c_read(int reg)
+{
+	struct tpa6130a2_data *data;
+	int val;
+
+	BUG_ON(tpa6130a2_client == NULL);
+	data = i2c_get_clientdata(tpa6130a2_client);
+
+	/* If powered off, return the cached value */
+	if (data->power_state) {
+		val = i2c_smbus_read_byte_data(tpa6130a2_client, reg);
+		if (val < 0)
+			dev_err(&tpa6130a2_client->dev, "Read failed\n");
+		else
+			data->regs[reg] = val;
+	} else {
+		val = data->regs[reg];
+	}
+
+	return val;
+}
+
+static int tpa6130a2_i2c_write(int reg, u8 value)
+{
+	struct tpa6130a2_data *data;
+	int val = 0;
+
+	BUG_ON(tpa6130a2_client == NULL);
+	data = i2c_get_clientdata(tpa6130a2_client);
+
+	if (data->power_state) {
+		val = i2c_smbus_write_byte_data(tpa6130a2_client, reg, value);
+		if (val < 0)
+			dev_err(&tpa6130a2_client->dev, "Write failed\n");
+	}
+
+	/* Either powered on or off, we save the context */
+	data->regs[reg] = value;
+
+	return val;
+}
+
+static u8 tpa6130a2_read(int reg)
+{
+	struct tpa6130a2_data *data;
+
+	BUG_ON(tpa6130a2_client == NULL);
+	data = i2c_get_clientdata(tpa6130a2_client);
+
+	return data->regs[reg];
+}
+
+static void tpa6130a2_initialize(void)
+{
+	struct tpa6130a2_data *data;
+	int i;
+
+	BUG_ON(tpa6130a2_client == NULL);
+	data = i2c_get_clientdata(tpa6130a2_client);
+
+	for (i = 1; i < TPA6130A2_REG_VERSION; i++)
+		tpa6130a2_i2c_write(i, data->regs[i]);
+}
+
+void tpa6130a2_power(int power)
+{
+	struct	tpa6130a2_data *data;
+	u8	val;
+
+	BUG_ON(tpa6130a2_client == NULL);
+	data = i2c_get_clientdata(tpa6130a2_client);
+
+	mutex_lock(&data->mutex);
+	if (power) {
+		/* Power on */
+		if (data->power_gpio >= 0) {
+			gpio_set_value(data->power_gpio, 1);
+			data->power_state = 1;
+			tpa6130a2_initialize();
+		}
+		/* Clear SWS */
+		val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
+		val &= ~TPA6130A2_SWS;
+		tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);
+	} else {
+		/* set SWS */
+		val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
+		val |= TPA6130A2_SWS;
+		tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);
+		/* Power off */
+		if (data->power_gpio >= 0) {
+			gpio_set_value(data->power_gpio, 0);
+			data->power_state = 0;
+		}
+	}
+	mutex_unlock(&data->mutex);
+}
+
+static int tpa6130a2_get_reg(struct snd_kcontrol *kcontrol,
+		struct snd_ctl_elem_value *ucontrol)
+{
+	struct soc_mixer_control *mc =
+		(struct soc_mixer_control *)kcontrol->private_value;
+	struct tpa6130a2_data *data;
+	unsigned int reg = mc->reg;
+	unsigned int shift = mc->shift;
+	unsigned int mask = mc->max;
+	unsigned int invert = mc->invert;
+
+	BUG_ON(tpa6130a2_client == NULL);
+	data = i2c_get_clientdata(tpa6130a2_client);
+
+	mutex_lock(&data->mutex);
+
+	ucontrol->value.integer.value[0] =
+		(tpa6130a2_read(reg) >> shift) & mask;
+
+	if (invert)
+		ucontrol->value.integer.value[0] =
+			mask - ucontrol->value.integer.value[0];
+
+	mutex_unlock(&data->mutex);
+	return 0;
+}
+
+static int tpa6130a2_set_reg(struct snd_kcontrol *kcontrol,
+		struct snd_ctl_elem_value *ucontrol)
+{
+	struct soc_mixer_control *mc =
+		(struct soc_mixer_control *)kcontrol->private_value;
+	struct tpa6130a2_data *data;
+	unsigned int reg = mc->reg;
+	unsigned int shift = mc->shift;
+	unsigned int mask = mc->max;
+	unsigned int invert = mc->invert;
+	unsigned int val = (ucontrol->value.integer.value[0] & mask);
+	unsigned int val_reg;
+
+	BUG_ON(tpa6130a2_client == NULL);
+	data = i2c_get_clientdata(tpa6130a2_client);
+
+	if (invert)
+		val = mask - val;
+
+	mutex_lock(&data->mutex);
+
+	val_reg = tpa6130a2_read(reg);
+	if (((val_reg >> shift) & mask) == val) {
+		mutex_unlock(&data->mutex);
+		return 0;
+	}
+
+	val_reg &= ~(mask << shift);
+	val_reg |= val << shift;
+	tpa6130a2_i2c_write(reg, val_reg);
+
+	mutex_unlock(&data->mutex);
+
+	return 1;
+}
+
+/*
+ * TPA6130 volume. From -59.5 to 4 dB with increasing step size when going
+ * down in gain.
+ */
+static const unsigned int tpa6130_tlv[] = {
+	TLV_DB_RANGE_HEAD(10),
+	0, 1, TLV_DB_SCALE_ITEM(-5950, 600, 0),
+	2, 3, TLV_DB_SCALE_ITEM(-5000, 250, 0),
+	4, 5, TLV_DB_SCALE_ITEM(-4550, 160, 0),
+	6, 7, TLV_DB_SCALE_ITEM(-4140, 190, 0),
+	8, 9, TLV_DB_SCALE_ITEM(-3650, 120, 0),
+	10, 11, TLV_DB_SCALE_ITEM(-3330, 160, 0),
+	12, 13, TLV_DB_SCALE_ITEM(-3040, 180, 0),
+	14, 20, TLV_DB_SCALE_ITEM(-2710, 110, 0),
+	21, 37, TLV_DB_SCALE_ITEM(-1960, 74, 0),
+	38, 63, TLV_DB_SCALE_ITEM(-720, 45, 0),
+};
+
+static const struct snd_kcontrol_new tpa6130a2_controls[] = {
+	SOC_SINGLE_EXT_TLV("TPA6130A2 Headphone Playback Volume",
+		       TPA6130A2_REG_VOL_MUTE, 0, 0x3f, 0,
+		       tpa6130a2_get_reg, tpa6130a2_set_reg,
+		       tpa6130_tlv),
+};
+
+/*
+ * Enable or disable channel (left or right)
+ * The bit number for mute and amplifier are the same per channel:
+ * bit 6: Right channel
+ * bit 7: Left channel
+ * in both registers.
+ */
+static void tpa6130a2_channel_enable(u8 channel, int enable)
+{
+	struct	tpa6130a2_data *data;
+	u8	val;
+
+	BUG_ON(tpa6130a2_client == NULL);
+	data = i2c_get_clientdata(tpa6130a2_client);
+
+	if (enable) {
+		/* Enable channel */
+		/* Enable amplifier */
+		val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
+		val |= channel;
+		tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);
+
+		/* Unmute channel */
+		val = tpa6130a2_read(TPA6130A2_REG_VOL_MUTE);
+		val &= ~channel;
+		tpa6130a2_i2c_write(TPA6130A2_REG_VOL_MUTE, val);
+	} else {
+		/* Disable channel */
+		/* Mute channel */
+		val = tpa6130a2_read(TPA6130A2_REG_VOL_MUTE);
+		val |= channel;
+		tpa6130a2_i2c_write(TPA6130A2_REG_VOL_MUTE, val);
+
+		/* Disable amplifier */
+		val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
+		val &= ~channel;
+		tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);
+	}
+}
+
+static int tpa6130a2_left_event(struct snd_soc_dapm_widget *w,
+		struct snd_kcontrol *kcontrol, int event)
+{
+	switch (event) {
+	case SND_SOC_DAPM_POST_PMU:
+		tpa6130a2_channel_enable(TPA6130A2_HP_EN_L, 1);
+		break;
+	case SND_SOC_DAPM_POST_PMD:
+		tpa6130a2_channel_enable(TPA6130A2_HP_EN_L, 0);
+		break;
+	}
+	return 0;
+}
+
+static int tpa6130a2_right_event(struct snd_soc_dapm_widget *w,
+		struct snd_kcontrol *kcontrol, int event)
+{
+	switch (event) {
+	case SND_SOC_DAPM_POST_PMU:
+		tpa6130a2_channel_enable(TPA6130A2_HP_EN_R, 1);
+		break;
+	case SND_SOC_DAPM_POST_PMD:
+		tpa6130a2_channel_enable(TPA6130A2_HP_EN_R, 0);
+		break;
+	}
+	return 0;
+}
+
+static int tpa6130a2_supply_event(struct snd_soc_dapm_widget *w,
+		struct snd_kcontrol *kcontrol, int event)
+{
+	switch (event) {
+	case SND_SOC_DAPM_POST_PMU:
+		tpa6130a2_power(1);
+		break;
+	case SND_SOC_DAPM_POST_PMD:
+		tpa6130a2_power(0);
+		break;
+	}
+	return 0;
+}
+
+static const struct snd_soc_dapm_widget tpa6130a2_dapm_widgets[] = {
+	SND_SOC_DAPM_PGA_E("TPA6130A2 Left", SND_SOC_NOPM,
+			0, 0, NULL, 0, tpa6130a2_left_event,
+			SND_SOC_DAPM_POST_PMU|SND_SOC_DAPM_POST_PMD),
+	SND_SOC_DAPM_PGA_E("TPA6130A2 Right", SND_SOC_NOPM,
+			0, 0, NULL, 0, tpa6130a2_right_event,
+			SND_SOC_DAPM_POST_PMU|SND_SOC_DAPM_POST_PMD),
+	SND_SOC_DAPM_SUPPLY("TPA6130A2 Enable", SND_SOC_NOPM,
+			0, 0, tpa6130a2_supply_event,
+			SND_SOC_DAPM_POST_PMU|SND_SOC_DAPM_POST_PMD),
+	/* Outputs */
+	SND_SOC_DAPM_HP("TPA6130A2 Headphone Left", NULL),
+	SND_SOC_DAPM_HP("TPA6130A2 Headphone Right", NULL),
+};
+
+static const struct snd_soc_dapm_route audio_map[] = {
+	{"TPA6130A2 Headphone Left", NULL, "TPA6130A2 Left"},
+	{"TPA6130A2 Headphone Right", NULL, "TPA6130A2 Right"},
+
+	{"TPA6130A2 Headphone Left", NULL, "TPA6130A2 Enable"},
+	{"TPA6130A2 Headphone Right", NULL, "TPA6130A2 Enable"},
+};
+
+int tpa6130a2_add_controls(struct snd_soc_codec *codec)
+{
+	snd_soc_dapm_new_controls(codec, tpa6130a2_dapm_widgets,
+				ARRAY_SIZE(tpa6130a2_dapm_widgets));
+
+	snd_soc_dapm_add_routes(codec, audio_map, ARRAY_SIZE(audio_map));
+
+	return snd_soc_add_controls(codec, tpa6130a2_controls,
+				ARRAY_SIZE(tpa6130a2_controls));
+
+}
+EXPORT_SYMBOL_GPL(tpa6130a2_add_controls);
+
+static int tpa6130a2_probe(struct i2c_client *client,
+			   const struct i2c_device_id *id)
+{
+	struct device *dev;
+	struct tpa6130a2_data *data;
+	struct tpa6130a2_platform_data *pdata;
+	int ret;
+
+	dev = &client->dev;
+
+	if (client->dev.platform_data == NULL) {
+		dev_err(dev, "Platform data not set\n");
+		dump_stack();
+		return -ENODEV;
+	}
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (data == NULL) {
+		dev_err(dev, "Can not allocate memory\n");
+		return -ENOMEM;
+	}
+
+	tpa6130a2_client = client;
+
+	i2c_set_clientdata(tpa6130a2_client, data);
+
+	pdata = (struct tpa6130a2_platform_data *)client->dev.platform_data;
+	data->power_gpio = pdata->power_gpio;
+
+	mutex_init(&data->mutex);
+
+	/* Set default register values */
+	data->regs[TPA6130A2_REG_CONTROL] =	TPA6130A2_SWS;
+	data->regs[TPA6130A2_REG_VOL_MUTE] =	TPA6130A2_MUTE_R |
+						TPA6130A2_MUTE_L;
+
+	if (data->power_gpio >= 0) {
+		ret = gpio_request(data->power_gpio, "tpa6130a2 enable");
+		if (ret < 0) {
+			dev_err(dev, "Failed to request power GPIO (%d)\n",
+				data->power_gpio);
+			goto fail;
+		}
+		gpio_direction_output(data->power_gpio, 0);
+	} else {
+		data->power_state = 1;
+		tpa6130a2_initialize();
+	}
+
+	tpa6130a2_power(1);
+
+	/* Read version */
+	ret = tpa6130a2_i2c_read(TPA6130A2_REG_VERSION) &
+				 TPA6130A2_VERSION_MASK;
+	if ((ret != 1) && (ret != 2))
+		dev_warn(dev, "UNTESTED version detected (%d)\n", ret);
+
+	/* Disable the chip */
+	tpa6130a2_power(0);
+
+	return 0;
+fail:
+	kfree(data);
+	i2c_set_clientdata(tpa6130a2_client, NULL);
+	tpa6130a2_client = 0;
+
+	return ret;
+}
+
+static int tpa6130a2_remove(struct i2c_client *client)
+{
+	struct tpa6130a2_data *data = i2c_get_clientdata(client);
+
+	tpa6130a2_power(0);
+
+	if (data->power_gpio >= 0)
+		gpio_free(data->power_gpio);
+	kfree(data);
+	tpa6130a2_client = 0;
+
+	return 0;
+}
+
+static const struct i2c_device_id tpa6130a2_id[] = {
+	{ "tpa6130a2", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, tpa6130a2_id);
+
+static struct i2c_driver tpa6130a2_i2c_driver = {
+	.driver = {
+		.name = "tpa6130a2",
+		.owner = THIS_MODULE,
+	},
+	.probe = tpa6130a2_probe,
+	.remove = __devexit_p(tpa6130a2_remove),
+	.id_table = tpa6130a2_id,
+};
+
+static int __init tpa6130a2_init(void)
+{
+	return i2c_add_driver(&tpa6130a2_i2c_driver);
+}
+
+static void __exit tpa6130a2_exit(void)
+{
+	i2c_del_driver(&tpa6130a2_i2c_driver);
+}
+
+MODULE_AUTHOR("Peter Ujfalusi");
+MODULE_DESCRIPTION("TPA6130A2 Headphone amplifier driver");
+MODULE_LICENSE("GPL");
+
+module_init(tpa6130a2_init);
+module_exit(tpa6130a2_exit);