[PATCH V2 3/4] ASoC: tas571x: New driver for TI TAS571x power amplifiers

From: Kevin Cernekee
Date: Fri Apr 24 2015 - 18:37:52 EST


Introduce a new codec driver for the Texas Instruments
TAS5711/TAS5717/TAS5719 power amplifier chips. These chips are typically
used to take an I2S digital audio input and drive 10-20W into a pair of
speakers.

Signed-off-by: Kevin Cernekee <cernekee@xxxxxxxxxxxx>
---
sound/soc/codecs/Kconfig | 5 +
sound/soc/codecs/Makefile | 2 +
sound/soc/codecs/tas571x.c | 521 +++++++++++++++++++++++++++++++++++++++++++++
sound/soc/codecs/tas571x.h | 33 +++
4 files changed, 561 insertions(+)
create mode 100644 sound/soc/codecs/tas571x.c
create mode 100644 sound/soc/codecs/tas571x.h

diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 061c46587628..befff910d71a 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -104,6 +104,7 @@ config SND_SOC_ALL_CODECS
select SND_SOC_STAC9766 if SND_SOC_AC97_BUS
select SND_SOC_TAS2552 if I2C
select SND_SOC_TAS5086 if I2C
+ select SND_SOC_TAS571X if I2C
select SND_SOC_TFA9879 if I2C
select SND_SOC_TLV320AIC23_I2C if I2C
select SND_SOC_TLV320AIC23_SPI if SPI_MASTER
@@ -611,6 +612,10 @@ config SND_SOC_TAS5086
tristate "Texas Instruments TAS5086 speaker amplifier"
depends on I2C

+config SND_SOC_TAS571X
+ tristate "Texas Instruments TAS5711/TAS5717/TAS5719 power amplifiers"
+ depends on I2C
+
config SND_SOC_TFA9879
tristate "NXP Semiconductors TFA9879 amplifier"
depends on I2C
diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile
index abe2d7edf65c..3dcf5ac85e89 100644
--- a/sound/soc/codecs/Makefile
+++ b/sound/soc/codecs/Makefile
@@ -106,6 +106,7 @@ snd-soc-sta350-objs := sta350.o
snd-soc-sta529-objs := sta529.o
snd-soc-stac9766-objs := stac9766.o
snd-soc-tas5086-objs := tas5086.o
+snd-soc-tas571x-objs := tas571x.o
snd-soc-tfa9879-objs := tfa9879.o
snd-soc-tlv320aic23-objs := tlv320aic23.o
snd-soc-tlv320aic23-i2c-objs := tlv320aic23-i2c.o
@@ -288,6 +289,7 @@ obj-$(CONFIG_SND_SOC_STA529) += snd-soc-sta529.o
obj-$(CONFIG_SND_SOC_STAC9766) += snd-soc-stac9766.o
obj-$(CONFIG_SND_SOC_TAS2552) += snd-soc-tas2552.o
obj-$(CONFIG_SND_SOC_TAS5086) += snd-soc-tas5086.o
+obj-$(CONFIG_SND_SOC_TAS571X) += snd-soc-tas571x.o
obj-$(CONFIG_SND_SOC_TFA9879) += snd-soc-tfa9879.o
obj-$(CONFIG_SND_SOC_TLV320AIC23) += snd-soc-tlv320aic23.o
obj-$(CONFIG_SND_SOC_TLV320AIC23_I2C) += snd-soc-tlv320aic23-i2c.o
diff --git a/sound/soc/codecs/tas571x.c b/sound/soc/codecs/tas571x.c
new file mode 100644
index 000000000000..08e358638f2e
--- /dev/null
+++ b/sound/soc/codecs/tas571x.c
@@ -0,0 +1,521 @@
+/*
+ * TAS571x amplifier audio driver
+ *
+ * Copyright (C) 2015 Google, Inc.
+ * Copyright (c) 2013 Daniel Mack <zonque@xxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/stddef.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/tlv.h>
+
+#include "tas571x.h"
+
+#define TAS571X_MAX_SUPPLIES 6
+
+struct tas571x_chip {
+ const char *const *supply_names;
+ int num_supply_names;
+ const struct snd_kcontrol_new *controls;
+ int num_controls;
+ const struct regmap_config *regmap_config;
+ int vol_reg_size;
+};
+
+struct tas571x_private {
+ const struct tas571x_chip *chip;
+ struct regmap *regmap;
+ struct regulator_bulk_data supplies[TAS571X_MAX_SUPPLIES];
+ struct clk *mclk;
+ unsigned int format;
+ struct gpio_desc *reset_gpio;
+ struct gpio_desc *pdn_gpio;
+ struct snd_soc_codec_driver codec_driver;
+};
+
+static int tas571x_register_size(struct tas571x_private *priv, unsigned int reg)
+{
+ switch (reg) {
+ case TAS571X_MVOL_REG:
+ case TAS571X_CH1_VOL_REG:
+ case TAS571X_CH2_VOL_REG:
+ return priv->chip->vol_reg_size;
+ default:
+ return 1;
+ }
+}
+
+static int tas571x_reg_write(void *context, unsigned int reg,
+ unsigned int value)
+{
+ struct i2c_client *client = context;
+ struct tas571x_private *priv = i2c_get_clientdata(client);
+ unsigned int i, size;
+ uint8_t buf[5];
+ int ret;
+
+ size = tas571x_register_size(priv, reg);
+ buf[0] = reg;
+
+ for (i = size; i >= 1; --i) {
+ buf[i] = value;
+ value >>= 8;
+ }
+
+ ret = i2c_master_send(client, buf, size + 1);
+ if (ret == size + 1)
+ return 0;
+ else if (ret < 0)
+ return ret;
+ else
+ return -EIO;
+}
+
+static int tas571x_reg_read(void *context, unsigned int reg,
+ unsigned int *value)
+{
+ struct i2c_client *client = context;
+ struct tas571x_private *priv = i2c_get_clientdata(client);
+ uint8_t send_buf, recv_buf[4];
+ struct i2c_msg msgs[2];
+ unsigned int size;
+ unsigned int i;
+ int ret;
+
+ size = tas571x_register_size(priv, reg);
+ send_buf = reg;
+
+ msgs[0].addr = client->addr;
+ msgs[0].len = sizeof(send_buf);
+ msgs[0].buf = &send_buf;
+ msgs[0].flags = 0;
+
+ msgs[1].addr = client->addr;
+ msgs[1].len = size;
+ msgs[1].buf = recv_buf;
+ msgs[1].flags = I2C_M_RD;
+
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (ret < 0)
+ return ret;
+ else if (ret != ARRAY_SIZE(msgs))
+ return -EIO;
+
+ *value = 0;
+
+ for (i = 0; i < size; i++) {
+ *value <<= 8;
+ *value |= recv_buf[i];
+ }
+
+ return 0;
+}
+
+static int tas571x_set_dai_fmt(struct snd_soc_dai *dai, unsigned int format)
+{
+ struct tas571x_private *priv = snd_soc_codec_get_drvdata(dai->codec);
+
+ priv->format = format;
+
+ return 0;
+}
+
+static int tas571x_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params,
+ struct snd_soc_dai *dai)
+{
+ struct tas571x_private *priv = snd_soc_codec_get_drvdata(dai->codec);
+ u32 val;
+
+ switch (priv->format & SND_SOC_DAIFMT_FORMAT_MASK) {
+ case SND_SOC_DAIFMT_RIGHT_J:
+ val = 0x00;
+ break;
+ case SND_SOC_DAIFMT_I2S:
+ val = 0x03;
+ break;
+ case SND_SOC_DAIFMT_LEFT_J:
+ val = 0x06;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (params_width(params) >= 24)
+ val += 2;
+ else if (params_width(params) >= 20)
+ val += 1;
+
+ return regmap_update_bits(priv->regmap, TAS571X_SDI_REG,
+ TAS571X_SDI_FMT_MASK, val);
+}
+
+static int tas571x_set_bias_level(struct snd_soc_codec *codec,
+ enum snd_soc_bias_level level)
+{
+ struct tas571x_private *priv = snd_soc_codec_get_drvdata(codec);
+ int ret;
+
+ 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) {
+ if (!IS_ERR(priv->mclk)) {
+ ret = clk_prepare_enable(priv->mclk);
+ if (ret) {
+ dev_err(codec->dev,
+ "Failed to enable master clock: %d\n",
+ ret);
+ return ret;
+ }
+ }
+
+ gpiod_set_value(priv->pdn_gpio, 0);
+ usleep_range(5000, 6000);
+
+ regcache_cache_only(priv->regmap, false);
+ ret = regcache_sync_region(priv->regmap, 0,
+ priv->chip->regmap_config->max_register, false);
+ if (ret)
+ return ret;
+ }
+ break;
+ case SND_SOC_BIAS_OFF:
+ regcache_cache_only(priv->regmap, true);
+ gpiod_set_value(priv->pdn_gpio, 1);
+
+ if (!IS_ERR(priv->mclk))
+ clk_disable_unprepare(priv->mclk);
+ break;
+ }
+
+ codec->dapm.bias_level = level;
+ return 0;
+}
+
+static const struct snd_soc_dai_ops tas571x_dai_ops = {
+ .set_fmt = tas571x_set_dai_fmt,
+ .hw_params = tas571x_hw_params,
+};
+
+static const char *const tas5711_supply_names[] = {
+ "AVDD",
+ "DVDD",
+ "PVDD_A",
+ "PVDD_B",
+ "PVDD_C",
+ "PVDD_D",
+};
+
+static const DECLARE_TLV_DB_SCALE(tas5711_volume_tlv, -10350, 50, 1);
+
+static const struct snd_kcontrol_new tas5711_controls[] = {
+ SOC_SINGLE_TLV("Master Volume",
+ TAS571X_MVOL_REG,
+ 0, 0xff, 1, tas5711_volume_tlv),
+ SOC_DOUBLE_R_TLV("Speaker Volume",
+ TAS571X_CH1_VOL_REG,
+ TAS571X_CH2_VOL_REG,
+ 0, 0xff, 1, tas5711_volume_tlv),
+ SOC_DOUBLE("Speaker Switch",
+ TAS571X_SOFT_MUTE_REG,
+ TAS571X_SOFT_MUTE_CH1_SHIFT, TAS571X_SOFT_MUTE_CH2_SHIFT,
+ 1, 1),
+};
+
+static const struct reg_default tas5711_reg_defaults[] = {
+ { 0x04, 0x05 },
+ { 0x05, 0x40 },
+ { 0x06, 0x00 },
+ { 0x07, 0xff },
+ { 0x08, 0x30 },
+ { 0x09, 0x30 },
+ { 0x1b, 0x82 },
+};
+
+static const struct regmap_config tas5711_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 32,
+ .max_register = 0xff,
+ .reg_read = tas571x_reg_read,
+ .reg_write = tas571x_reg_write,
+ .reg_defaults = tas5711_reg_defaults,
+ .num_reg_defaults = ARRAY_SIZE(tas5711_reg_defaults),
+ .cache_type = REGCACHE_RBTREE,
+};
+
+static const struct tas571x_chip tas5711_chip = {
+ .supply_names = tas5711_supply_names,
+ .num_supply_names = ARRAY_SIZE(tas5711_supply_names),
+ .controls = tas5711_controls,
+ .num_controls = ARRAY_SIZE(tas5711_controls),
+ .regmap_config = &tas5711_regmap_config,
+ .vol_reg_size = 1,
+};
+
+static const char *const tas5717_supply_names[] = {
+ "AVDD",
+ "DVDD",
+ "HPVDD",
+ "PVDD_AB",
+ "PVDD_CD",
+};
+
+static const DECLARE_TLV_DB_SCALE(tas5717_volume_tlv, -10375, 25, 0);
+
+static const struct snd_kcontrol_new tas5717_controls[] = {
+ /* MVOL LSB is ignored - see comments in tas571x_i2c_probe() */
+ SOC_SINGLE_TLV("Master Volume",
+ TAS571X_MVOL_REG, 1, 0x1ff, 1,
+ tas5717_volume_tlv),
+ SOC_DOUBLE_R_TLV("Speaker Volume",
+ TAS571X_CH1_VOL_REG, TAS571X_CH2_VOL_REG,
+ 1, 0x1ff, 1, tas5717_volume_tlv),
+ SOC_DOUBLE("Speaker Switch",
+ TAS571X_SOFT_MUTE_REG,
+ TAS571X_SOFT_MUTE_CH1_SHIFT, TAS571X_SOFT_MUTE_CH2_SHIFT,
+ 1, 1),
+};
+
+static const struct reg_default tas5717_reg_defaults[] = {
+ { 0x04, 0x05 },
+ { 0x05, 0x40 },
+ { 0x06, 0x00 },
+ { 0x07, 0x03ff },
+ { 0x08, 0x00c0 },
+ { 0x09, 0x00c0 },
+ { 0x1b, 0x82 },
+};
+
+static const struct regmap_config tas5717_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 32,
+ .max_register = 0xff,
+ .reg_read = tas571x_reg_read,
+ .reg_write = tas571x_reg_write,
+ .reg_defaults = tas5717_reg_defaults,
+ .num_reg_defaults = ARRAY_SIZE(tas5717_reg_defaults),
+ .cache_type = REGCACHE_RBTREE,
+};
+
+/* This entry is reused for tas5719 as the software interface is identical. */
+static const struct tas571x_chip tas5717_chip = {
+ .supply_names = tas5717_supply_names,
+ .num_supply_names = ARRAY_SIZE(tas5717_supply_names),
+ .controls = tas5717_controls,
+ .num_controls = ARRAY_SIZE(tas5717_controls),
+ .regmap_config = &tas5717_regmap_config,
+ .vol_reg_size = 2,
+};
+
+static const struct snd_soc_dapm_widget tas571x_dapm_widgets[] = {
+ SND_SOC_DAPM_DAC("DACL", NULL, SND_SOC_NOPM, 0, 0),
+ SND_SOC_DAPM_DAC("DACR", NULL, SND_SOC_NOPM, 0, 0),
+
+ SND_SOC_DAPM_OUTPUT("OUT_A"),
+ SND_SOC_DAPM_OUTPUT("OUT_B"),
+ SND_SOC_DAPM_OUTPUT("OUT_C"),
+ SND_SOC_DAPM_OUTPUT("OUT_D"),
+};
+
+static const struct snd_soc_dapm_route tas571x_dapm_routes[] = {
+ { "DACL", NULL, "Playback" },
+ { "DACR", NULL, "Playback" },
+
+ { "OUT_A", NULL, "DACL" },
+ { "OUT_B", NULL, "DACL" },
+ { "OUT_C", NULL, "DACR" },
+ { "OUT_D", NULL, "DACR" },
+};
+
+static const struct snd_soc_codec_driver tas571x_codec = {
+ .set_bias_level = tas571x_set_bias_level,
+ .idle_bias_off = true,
+
+ .dapm_widgets = tas571x_dapm_widgets,
+ .num_dapm_widgets = ARRAY_SIZE(tas571x_dapm_widgets),
+ .dapm_routes = tas571x_dapm_routes,
+ .num_dapm_routes = ARRAY_SIZE(tas571x_dapm_routes),
+};
+
+static struct snd_soc_dai_driver tas571x_dai = {
+ .name = "tas571x-hifi",
+ .playback = {
+ .stream_name = "Playback",
+ .channels_min = 2,
+ .channels_max = 2,
+ .rates = SNDRV_PCM_RATE_8000_48000,
+ .formats = SNDRV_PCM_FMTBIT_S32_LE |
+ SNDRV_PCM_FMTBIT_S24_LE |
+ SNDRV_PCM_FMTBIT_S16_LE,
+ },
+ .ops = &tas571x_dai_ops,
+};
+
+static const struct of_device_id tas571x_of_match[];
+
+static int tas571x_i2c_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct tas571x_private *priv;
+ struct device *dev = &client->dev;
+ int i, ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+ i2c_set_clientdata(client, priv);
+
+ if (dev->of_node) {
+ const struct of_device_id *of_id;
+
+ of_id = of_match_device(tas571x_of_match, dev);
+ if (of_id)
+ priv->chip = of_id->data;
+ }
+
+ if (!priv->chip) {
+ dev_err(dev, "Unknown device type\n");
+ return -EINVAL;
+ }
+
+ priv->mclk = devm_clk_get(dev, "mclk");
+ if (IS_ERR(priv->mclk) && PTR_ERR(priv->mclk) != -ENOENT) {
+ dev_err(dev, "Failed to request mclk: %ld\n",
+ PTR_ERR(priv->mclk));
+ return PTR_ERR(priv->mclk);
+ }
+
+ BUG_ON(priv->chip->num_supply_names > TAS571X_MAX_SUPPLIES);
+ for (i = 0; i < priv->chip->num_supply_names; i++)
+ priv->supplies[i].supply = priv->chip->supply_names[i];
+
+ ret = devm_regulator_bulk_get(dev, priv->chip->num_supply_names,
+ priv->supplies);
+ if (ret) {
+ dev_err(dev, "Failed to get supplies: %d\n", ret);
+ return ret;
+ }
+ ret = regulator_bulk_enable(priv->chip->num_supply_names,
+ priv->supplies);
+ if (ret) {
+ dev_err(dev, "Failed to enable supplies: %d\n", ret);
+ return ret;
+ }
+
+ priv->regmap = devm_regmap_init(dev, NULL, client,
+ priv->chip->regmap_config);
+ if (IS_ERR(priv->regmap))
+ return PTR_ERR(priv->regmap);
+
+ priv->pdn_gpio = devm_gpiod_get_optional(dev, "pdn", GPIOD_OUT_LOW);
+ if (IS_ERR(priv->pdn_gpio)) {
+ dev_err(dev, "error requesting pdn_gpio: %ld\n",
+ PTR_ERR(priv->pdn_gpio));
+ return PTR_ERR(priv->pdn_gpio);
+ }
+
+ priv->reset_gpio = devm_gpiod_get_optional(dev, "reset",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(priv->reset_gpio)) {
+ dev_err(dev, "error requesting reset_gpio: %ld\n",
+ PTR_ERR(priv->reset_gpio));
+ return PTR_ERR(priv->reset_gpio);
+ } else if (priv->reset_gpio) {
+ /* pulse the active low reset line for ~100us */
+ usleep_range(100, 200);
+ gpiod_set_value(priv->reset_gpio, 0);
+ usleep_range(12000, 20000);
+ }
+
+ ret = regmap_write(priv->regmap, TAS571X_OSC_TRIM_REG, 0);
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(priv->regmap, TAS571X_SYS_CTRL_2_REG,
+ TAS571X_SYS_CTRL_2_SDN_MASK, 0);
+ if (ret)
+ return ret;
+
+ memcpy(&priv->codec_driver, &tas571x_codec, sizeof(priv->codec_driver));
+ priv->codec_driver.controls = priv->chip->controls;
+ priv->codec_driver.num_controls = priv->chip->num_controls;
+
+ if (priv->chip->vol_reg_size == 2) {
+ /*
+ * The master volume defaults to 0x3ff (mute), but we ignore
+ * (zero) the LSB because the hardware step size is 0.125 dB
+ * and TLV_DB_SCALE_ITEM has a resolution of 0.01 dB.
+ */
+ ret = regmap_update_bits(priv->regmap, TAS571X_MVOL_REG, 1, 0);
+ if (ret)
+ return ret;
+ }
+
+ regcache_cache_only(priv->regmap, true);
+ gpiod_set_value(priv->pdn_gpio, 1);
+
+ return snd_soc_register_codec(&client->dev, &priv->codec_driver,
+ &tas571x_dai, 1);
+}
+
+static int tas571x_i2c_remove(struct i2c_client *client)
+{
+ struct tas571x_private *priv = i2c_get_clientdata(client);
+
+ snd_soc_unregister_codec(&client->dev);
+ regulator_bulk_disable(priv->chip->num_supply_names, priv->supplies);
+
+ return 0;
+}
+
+static const struct of_device_id tas571x_of_match[] = {
+ { .compatible = "ti,tas5711", .data = &tas5711_chip, },
+ { .compatible = "ti,tas5717", .data = &tas5717_chip, },
+ { .compatible = "ti,tas5719", .data = &tas5717_chip, },
+ { }
+};
+MODULE_DEVICE_TABLE(of, tas571x_of_match);
+
+static const struct i2c_device_id tas571x_i2c_id[] = {
+ { "tas5711", 0 },
+ { "tas5717", 0 },
+ { "tas5719", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, tas571x_i2c_id);
+
+static struct i2c_driver tas571x_i2c_driver = {
+ .driver = {
+ .name = "tas571x",
+ .of_match_table = of_match_ptr(tas571x_of_match),
+ },
+ .probe = tas571x_i2c_probe,
+ .remove = tas571x_i2c_remove,
+ .id_table = tas571x_i2c_id,
+};
+module_i2c_driver(tas571x_i2c_driver);
+
+MODULE_DESCRIPTION("ASoC TAS571x driver");
+MODULE_AUTHOR("Kevin Cernekee <cernekee@xxxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
diff --git a/sound/soc/codecs/tas571x.h b/sound/soc/codecs/tas571x.h
new file mode 100644
index 000000000000..0aee471232cd
--- /dev/null
+++ b/sound/soc/codecs/tas571x.h
@@ -0,0 +1,33 @@
+/*
+ * TAS571x amplifier audio driver
+ *
+ * Copyright (C) 2015 Google, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef _TAS571X_H
+#define _TAS571X_H
+
+/* device registers */
+#define TAS571X_SDI_REG 0x04
+#define TAS571X_SDI_FMT_MASK 0x0f
+
+#define TAS571X_SYS_CTRL_2_REG 0x05
+#define TAS571X_SYS_CTRL_2_SDN_MASK 0x40
+
+#define TAS571X_SOFT_MUTE_REG 0x06
+#define TAS571X_SOFT_MUTE_CH1_SHIFT 0
+#define TAS571X_SOFT_MUTE_CH2_SHIFT 1
+#define TAS571X_SOFT_MUTE_CH3_SHIFT 2
+
+#define TAS571X_MVOL_REG 0x07
+#define TAS571X_CH1_VOL_REG 0x08
+#define TAS571X_CH2_VOL_REG 0x09
+
+#define TAS571X_OSC_TRIM_REG 0x1b
+
+#endif /* _TAS571X_H */
--
2.2.0.rc0.207.ga3a616c

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