diff mbox

[2/2] ASoC: codecs: add support for TAS5720 digital amplifier

Message ID 1458343678-4086-3-git-send-email-dannenberg@ti.com
State New
Headers show

Commit Message

Andreas Dannenberg March 18, 2016, 11:27 p.m. UTC
The Texas Instruments TAS5720L/M device is a high-efficiency mono
Class-D audio power amplifier optimized for high transient power
capability to use the dynamic power headroom of small loudspeakers.
Its digital time division multiplexed (TDM) interface enables up to
16 devices to share the same bus.

Signed-off-by: Andreas Dannenberg <dannenberg@ti.com>

---
 sound/soc/codecs/Kconfig   |  10 +
 sound/soc/codecs/Makefile  |   2 +
 sound/soc/codecs/tas5720.c | 733 +++++++++++++++++++++++++++++++++++++++++++++
 sound/soc/codecs/tas5720.h |  90 ++++++
 4 files changed, 835 insertions(+)
 create mode 100644 sound/soc/codecs/tas5720.c
 create mode 100644 sound/soc/codecs/tas5720.h

-- 
2.6.4

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diff mbox

Patch

diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 7ef3a0c..a0bb8cb 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -124,6 +124,7 @@  config SND_SOC_ALL_CODECS
 	select SND_SOC_TAS2552 if I2C
 	select SND_SOC_TAS5086 if I2C
 	select SND_SOC_TAS571X if I2C
+	select SND_SOC_TAS5720 if I2C
 	select SND_SOC_TFA9879 if I2C
 	select SND_SOC_TLV320AIC23_I2C if I2C
 	select SND_SOC_TLV320AIC23_SPI if SPI_MASTER
@@ -741,6 +742,15 @@  config SND_SOC_TAS571X
 	tristate "Texas Instruments TAS5711/TAS5717/TAS5719 power amplifiers"
 	depends on I2C
 
+config SND_SOC_TAS5720
+	tristate "Texas Instruments TAS5720 Mono Audio amplifier"
+	depends on I2C
+	help
+	  Enable support for Texas Instruments TAS5720L/M high-efficiency mono
+	  Class-D audio power amplifiers. The devices use an I2C interface for
+	  setup/control and support an optional GPIO interrupt signal for fault
+	  reporting.
+
 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 185a712..83d352e 100644
--- a/sound/soc/codecs/Makefile
+++ b/sound/soc/codecs/Makefile
@@ -129,6 +129,7 @@  snd-soc-stac9766-objs := stac9766.o
 snd-soc-sti-sas-objs := sti-sas.o
 snd-soc-tas5086-objs := tas5086.o
 snd-soc-tas571x-objs := tas571x.o
+snd-soc-tas5720-objs := tas5720.o
 snd-soc-tfa9879-objs := tfa9879.o
 snd-soc-tlv320aic23-objs := tlv320aic23.o
 snd-soc-tlv320aic23-i2c-objs := tlv320aic23-i2c.o
@@ -335,6 +336,7 @@  obj-$(CONFIG_SND_SOC_STI_SAS)	+= snd-soc-sti-sas.o
 obj-$(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-$(CONFIG_SND_SOC_TAS5720)	+= snd-soc-tas5720.o
 obj-$(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/tas5720.c b/sound/soc/codecs/tas5720.c
new file mode 100644
index 0000000..ac22c22
--- /dev/null
+++ b/sound/soc/codecs/tas5720.c
@@ -0,0 +1,733 @@ 
+/*
+ * tas5720.c - ALSA SoC Texas Instruments TAS5720 Mono Audio Amplifier
+ *
+ * Copyright (C)2015-2016 Texas Instruments Incorporated -  http://www.ti.com
+ *
+ * Author: Andreas Dannenberg <dannenberg@ti.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.
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/regulator/consumer.h>
+#include <linux/delay.h>
+
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/soc-dapm.h>
+#include <sound/tlv.h>
+
+#include "tas5720.h"
+
+static const char * const tas5720_supply_names[] = {
+	"dvdd",		/* Digital power supply. Connect to 3.3-V supply. */
+	"pvdd",		/* Class-D amp and analog power supply (connected). */
+};
+#define TAS5720_NUM_SUPPLIES	ARRAY_SIZE(tas5720_supply_names)
+
+struct tas5720_data {
+	struct snd_soc_codec *codec;
+	struct regmap *regmap;
+	struct i2c_client *tas5720_client;
+	struct regulator_bulk_data supplies[TAS5720_NUM_SUPPLIES];
+	struct gpio_desc *gpiod_faultz;
+	struct delayed_work irq_enable_work;
+};
+
+static int tas5720_hw_params(struct snd_pcm_substream *substream,
+			     struct snd_pcm_hw_params *params,
+			     struct snd_soc_dai *dai)
+{
+	struct snd_soc_codec *codec = dai->codec;
+	int width = params_width(params);
+	unsigned int rate = params_rate(params);
+	bool ssz_ds;
+	int ret;
+
+	switch (width) {
+	case 16:
+	case 18:
+	case 20:
+	case 24:
+		/*
+		 * We only support the different left-justified serial audio
+		 * formats in which case there is nothing to configure in the
+		 * TAS5720.
+		 */
+		break;
+	default:
+		dev_err(codec->dev, "unsupported sample size: %d\n", width);
+		return -EINVAL;
+	}
+
+	switch (rate) {
+	case 44100:
+	case 48000:
+		ssz_ds = false;
+		break;
+	case 88200:
+	case 96000:
+		ssz_ds = true;
+		break;
+	default:
+		dev_err(codec->dev, "unsupported sample rate: %u\n", rate);
+		return -EINVAL;
+	}
+
+	ret = snd_soc_update_bits(codec, TAS5720_DIGITAL_CTRL1_REG,
+				  TAS5720_SSZ_DS, ssz_ds);
+	if (ret < 0) {
+		dev_err(codec->dev, "error setting sample rate: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int tas5720_set_dai_fmt(struct snd_soc_dai *dai, unsigned int fmt)
+{
+	struct snd_soc_codec *codec = dai->codec;
+	u8 serial_format;
+	int ret;
+
+	if ((fmt & SND_SOC_DAIFMT_MASTER_MASK) != SND_SOC_DAIFMT_CBS_CFS) {
+		dev_vdbg(codec->dev, "DAI Format master is not found\n");
+		return -EINVAL;
+	}
+
+	switch (fmt & (SND_SOC_DAIFMT_FORMAT_MASK |
+		       SND_SOC_DAIFMT_INV_MASK)) {
+	case (SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF):
+		/* 1st data bit occur one BCLK cycle after the frame sync */
+		serial_format = TAS5720_SAIF_I2S;
+		break;
+	case (SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_NB_NF):
+		/*
+		 * Note that although the TAS5720 does not have a dedicated DSP
+		 * mode it doesn't care about the LRCLK duty cycle during TDM
+		 * operation. Therefore we can use the device's I2S mode with
+		 * its delaying of the 1st data bit to receive DSP_A formatted
+		 * data. See device datasheet for additional details.
+		 */
+		serial_format = TAS5720_SAIF_I2S;
+		break;
+	case (SND_SOC_DAIFMT_DSP_B | SND_SOC_DAIFMT_NB_NF):
+		/*
+		 * Similar to DSP_A, we can use the fact that the TAS5720 does
+		 * not care about the LRCLK duty cycle during TDM to receive
+		 * DSP_B formatted data in LEFTJ mode (no delaying of the 1st
+		 * data bit).
+		 */
+		serial_format = TAS5720_SAIF_LEFTJ;
+		break;
+	case (SND_SOC_DAIFMT_LEFT_J | SND_SOC_DAIFMT_NB_NF):
+		/* No delay after the frame sync */
+		serial_format = TAS5720_SAIF_LEFTJ;
+		break;
+	default:
+		dev_vdbg(codec->dev, "DAI Format is not found\n");
+		return -EINVAL;
+	}
+
+	ret = snd_soc_update_bits(codec, TAS5720_DIGITAL_CTRL1_REG,
+				  TAS5720_SAIF_FORMAT_MASK,
+				  serial_format);
+	if (ret < 0) {
+		dev_err(codec->dev, "error setting SAIF format: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int tas5720_set_dai_sysclk(struct snd_soc_dai *dai, int clk_id,
+				  unsigned int freq, int dir)
+{
+	/*
+	 * Nothing to configure here for TAS5720. It's a simple codec slave.
+	 * However we need to keep this function in here otherwise the ASoC
+	 * platform driver will throw an ENOTSUPP at us when trying to play
+	 * audio.
+	 */
+
+	return 0;
+}
+
+static int tas5720_set_dai_tdm_slot(struct snd_soc_dai *dai,
+				    unsigned int tx_mask, unsigned int rx_mask,
+				    int slots, int slot_width)
+{
+	struct snd_soc_codec *codec = dai->codec;
+	unsigned int first_slot;
+	int ret;
+
+	if (unlikely(!tx_mask)) {
+		dev_err(codec->dev, "tx masks must not be 0\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Determine the first slot that is being requested. We will only
+	 * use the first slot that is found since the TAS5720 is a mono
+	 * amplifier.
+	 */
+	first_slot = __ffs(tx_mask);
+
+	if (first_slot > 7) {
+		dev_err(codec->dev, "slot selection out of bounds (%u)\n",
+			first_slot);
+		return -EINVAL;
+	}
+
+	/* Enable manual TDM slot selection (instead of I2C ID based) */
+	ret = snd_soc_update_bits(codec, TAS5720_DIGITAL_CTRL1_REG,
+				  TAS5720_TDM_CFG_SRC, TAS5720_TDM_CFG_SRC);
+	if (ret < 0)
+		goto error_snd_soc_update_bits;
+
+	/* Configure the TDM slot to process audio from */
+	ret = snd_soc_update_bits(codec, TAS5720_DIGITAL_CTRL2_REG,
+				  TAS5720_TDM_SLOT_SEL_MASK, first_slot);
+	if (ret < 0)
+		goto error_snd_soc_update_bits;
+
+	return 0;
+
+error_snd_soc_update_bits:
+	dev_err(codec->dev, "error configuring TDM mode: %d\n", ret);
+	return ret;
+}
+
+static int tas5720_mute(struct snd_soc_dai *dai, int mute)
+{
+	struct snd_soc_codec *codec = dai->codec;
+	int ret;
+
+	ret = snd_soc_update_bits(codec, TAS5720_DIGITAL_CTRL2_REG,
+				  TAS5720_MUTE, mute ? TAS5720_MUTE : 0);
+	if (ret < 0) {
+		dev_err(codec->dev, "error (un-)muting device: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static irqreturn_t tas5720_irq_handler(int irq, void *_dev)
+{
+	/*
+	 * Immediately disable TAS5720 FAULTZ interrupts inside the low-level
+	 * handler to prevent the system getting saturated or even overrun
+	 * by interrupt requests. Normally the fact that we create a threaded
+	 * interrupt with IRQF_ONESHOT should take care of this as by design
+	 * it masks interrupts while the thread is processed however testing
+	 * has shown that at the high frequency the FAULTZ signal triggers
+	 * (every 300us!) occasionally the system would lock up even with a
+	 * threaded handler that's completely empty until the Kernel breaks the
+	 * cycle, disables that interrupt, and reports a "nobody cared" error.
+	 *
+	 * Disabling the interrupt here combined with a deferred re-enabling
+	 * after the thread has run not only prevents this lock condition but
+	 * also helps to rate-limit the processing of FAULTZ interrupts.
+	 */
+	disable_irq_nosync(irq);
+
+	return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t tas5720_irq_thread(int irq, void *_dev)
+{
+	struct device *dev = _dev;
+	struct tas5720_data *tas5720 = dev_get_drvdata(dev);
+	unsigned int fault_val;
+	int ret;
+
+	ret = regmap_read(tas5720->regmap, TAS5720_FAULT_REG, &fault_val);
+	if (ret < 0) {
+		dev_err(dev, "failed to read FAULT register: %d\n", ret);
+		goto out;
+	}
+
+	/*
+	 * Check all errors except SAIF clock errors which can only be checked
+	 * during actual audio playback. However currently there is no good way
+	 * to start allowing those checks just after the audio stream is being
+	 * output and vice versa. Note that we rely on a connection between the
+	 * TAS5720 SDZ and FAULTZ pins to automatically clear and recover from
+	 * error conditions. See the "Auto Recovery Circuit" in the datasheet
+	 * for further information.
+	 */
+	if (fault_val & TAS5720_OCE)
+		dev_warn(dev, "The Class-D output stage has experienced an over current event\n");
+
+	if (fault_val & TAS5720_DCE)
+		dev_warn(dev, "The Class-D output stage has experienced a DC detect error\n");
+
+	if (fault_val & TAS5720_OTE)
+		dev_warn(dev, "The Class-D output stage has experienced an over temperature error\n");
+
+	/*
+	 * Re-enable interrupts 100ms after this handler has finished. This
+	 * will allow us to rate-limit the TAS5720-generated SAIF interrupt
+	 * storm that starts once the audio signal is shut off while the
+	 * device has not yet entered shutdown mode.
+	 *
+	 * We chose 100ms to strike a reasonable balance between reacting to
+	 * actual fault conditions quickly while not overwhelming the system
+	 * as checking the fault condition involves expensive I2C operations.
+	 */
+out:
+	ret = schedule_delayed_work(&tas5720->irq_enable_work,
+				    msecs_to_jiffies(100));
+	if (!ret) {
+		/*
+		 * This should never happen, but just as another safety net
+		 * add some error reporting nevertheless. If we do get this
+		 * error that's bad since it likely means that our interrupt
+		 * disable/enable scheme became unbalanced and with this the
+		 * fault reporting stopped functioning.
+		 */
+		dev_err(dev, "scheduled irq enable work already in queue!\n");
+	}
+
+	return IRQ_HANDLED;
+}
+
+static void tas5720_irq_enable_work(struct work_struct *work)
+{
+	struct tas5720_data *tas5720 =
+		container_of(work, struct tas5720_data, irq_enable_work.work);
+	int irq = tas5720->tas5720_client->irq;
+
+	enable_irq(irq);
+}
+
+static int tas5720_codec_probe(struct snd_soc_codec *codec)
+{
+	struct tas5720_data *tas5720 = snd_soc_codec_get_drvdata(codec);
+	int irq = tas5720->tas5720_client->irq;
+	unsigned int device_id;
+	int ret;
+
+	tas5720->codec = codec;
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(tas5720->supplies),
+				    tas5720->supplies);
+	if (ret != 0) {
+		dev_err(codec->dev, "failed to enable supplies: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_read(tas5720->regmap, TAS5720_DEVICE_ID_REG, &device_id);
+	if (ret < 0) {
+		dev_err(codec->dev, "failed to read device ID register: %d\n",
+			ret);
+		goto probe_fail;
+	}
+
+	if (device_id != TAS5720_DEVICE_ID) {
+		dev_err(codec->dev, "wrong device ID. expected: %u read: %u\n",
+			TAS5720_DEVICE_ID, device_id);
+		ret = -ENODEV;
+		goto probe_fail;
+	}
+
+	/* Set device to mute */
+	ret = snd_soc_update_bits(codec, TAS5720_DIGITAL_CTRL2_REG,
+				  TAS5720_MUTE, TAS5720_MUTE);
+	if (ret < 0)
+		goto error_snd_soc_update_bits;
+
+	/*
+	 * Enter shutdown mode - our default when not playing audio. This has
+	 * also the desired side-effect of squelching TAS5720-generated fault
+	 * interrupts (that can't be masked on the TAS5720 itself in a more
+	 * elegant fashion) before we install the IRQ handler so that we don't
+	 * get hammered with interrupts that we are not yet interested in.
+	 */
+	ret = snd_soc_update_bits(codec, TAS5720_POWER_CTRL_REG,
+				  TAS5720_SDZ, 0);
+	if (ret < 0)
+		goto error_snd_soc_update_bits;
+
+	/*
+	 * The use of a fault interrupt is optional. If used, the processor
+	 * interrupt signal should be connected to the TAS5720 FAULTZ pin.
+	 * Note that the connection between the TAS5720 FAULTZ and SDZ pins
+	 * should always be made to allow automatic fault recovery.
+	 */
+	if (irq > 0) {
+		ret = request_threaded_irq(irq,
+					   tas5720_irq_handler,
+					   tas5720_irq_thread,
+					   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+					   "tas5720", codec->dev);
+		if (ret) {
+			dev_err(codec->dev, "failed to request IRQ #%d\n", irq);
+			return ret;
+		}
+
+		dev_info(codec->dev, "using host FAULTZ reporting\n");
+	}
+
+	INIT_DELAYED_WORK(&tas5720->irq_enable_work, tas5720_irq_enable_work);
+
+	return 0;
+
+error_snd_soc_update_bits:
+	dev_err(codec->dev, "error configuring device registers: %d\n", ret);
+
+probe_fail:
+	regulator_bulk_disable(ARRAY_SIZE(tas5720->supplies),
+			       tas5720->supplies);
+	return ret;
+}
+
+static int tas5720_codec_remove(struct snd_soc_codec *codec)
+{
+	struct tas5720_data *tas5720 = snd_soc_codec_get_drvdata(codec);
+	int irq = tas5720->tas5720_client->irq;
+	int ret;
+
+	cancel_delayed_work_sync(&tas5720->irq_enable_work);
+
+	if (irq > 0)
+		free_irq(irq, codec->dev);
+
+	ret = regulator_bulk_disable(ARRAY_SIZE(tas5720->supplies),
+				     tas5720->supplies);
+	if (ret < 0)
+		dev_err(codec->dev, "failed to disable supplies: %d\n", ret);
+
+	return ret;
+};
+
+static int tas5720_dapm_post_event(struct snd_soc_dapm_widget *w,
+				   struct snd_kcontrol *kcontrol, int event)
+{
+	struct snd_soc_codec *codec = snd_soc_dapm_to_codec(w->dapm);
+	int ret;
+
+	switch (event) {
+	case SND_SOC_DAPM_POST_PMU:
+		/*
+		 * Check if the codec is still powered up in which case exit
+		 * right away also skipping the shutdown-to-active wait time.
+		 */
+		ret = snd_soc_test_bits(codec, TAS5720_POWER_CTRL_REG,
+					TAS5720_SDZ, 0);
+		if (ret < 0) {
+			dev_err(codec->dev, "error reading codec: %d\n", ret);
+			return ret;
+		} else if (ret) {
+			break;
+		}
+
+		/*
+		 * Take TAS5720 out of shutdown mode in preparation for widget
+		 * power up.
+		 */
+		ret = snd_soc_update_bits(codec, TAS5720_POWER_CTRL_REG,
+					  TAS5720_SDZ, TAS5720_SDZ);
+		if (ret < 0) {
+			dev_err(codec->dev, "error waking codec: %d\n", ret);
+			return ret;
+		}
+
+		/*
+		 * Observe codec shutdown-to-active time. The datasheet only
+		 * lists a nominal value however just use-it as-is without
+		 * additional padding to minimize the delay introduced in
+		 * starting to play audio (actually there is other setup done
+		 * by the ASoC framework that will provide additional delays,
+		 * so we should always be safe).
+		 */
+		msleep(25);
+		break;
+	}
+
+	return 0;
+}
+
+static int tas5720_dapm_pre_event(struct snd_soc_dapm_widget *w,
+				  struct snd_kcontrol *kcontrol, int event)
+{
+	struct snd_soc_codec *codec = snd_soc_dapm_to_codec(w->dapm);
+	int ret;
+
+	switch (event) {
+	case SND_SOC_DAPM_PRE_PMD:
+		/*
+		 * Place TAS5720 in shutdown mode in preparation for widget
+		 * power down. As a desired side effect, this will also prevent
+		 * the TAS5270 from inundating the host with SAIF fault
+		 * interrupts (if used)
+		 */
+		ret = snd_soc_update_bits(codec, TAS5720_POWER_CTRL_REG,
+					  TAS5720_SDZ, 0);
+		if (ret < 0) {
+			dev_err(codec->dev, "error shutting down codec: %d\n",
+				ret);
+			return ret;
+		}
+		break;
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int tas5720_suspend(struct snd_soc_codec *codec)
+{
+	struct tas5720_data *tas5720 = snd_soc_codec_get_drvdata(codec);
+	int ret;
+
+	regcache_cache_only(tas5720->regmap, true);
+	regcache_mark_dirty(tas5720->regmap);
+
+	ret = regulator_bulk_disable(ARRAY_SIZE(tas5720->supplies),
+				     tas5720->supplies);
+	if (ret < 0)
+		dev_err(codec->dev, "failed to disable supplies: %d\n", ret);
+
+	return ret;
+}
+
+static int tas5720_resume(struct snd_soc_codec *codec)
+{
+	struct tas5720_data *tas5720 = snd_soc_codec_get_drvdata(codec);
+	int ret;
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(tas5720->supplies),
+				    tas5720->supplies);
+	if (ret < 0) {
+		dev_err(codec->dev, "failed to enable supplies: %d\n", ret);
+		return ret;
+	}
+
+	regcache_cache_only(tas5720->regmap, false);
+
+	ret = regcache_sync(tas5720->regmap);
+	if (ret < 0) {
+		dev_err(codec->dev, "failed to sync regcache: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+#else
+#define tas5720_suspend NULL
+#define tas5720_resume NULL
+#endif
+
+static bool tas5720_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case TAS5720_DEVICE_ID_REG:
+	case TAS5720_FAULT_REG:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static const struct regmap_config tas5720_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+
+	.max_register = TAS5720_MAX_REG,
+	.cache_type = REGCACHE_RBTREE,
+	.volatile_reg = tas5720_is_volatile_reg,
+};
+
+/*
+ * DAC analog gain. There are four discrete values to select from, ranging
+ * from 19.2 dB to 26.3dB.
+ */
+static const DECLARE_TLV_DB_RANGE(dac_analog_tlv,
+	0x0, 0x0, TLV_DB_SCALE_ITEM(1920, 0, 0),
+	0x1, 0x1, TLV_DB_SCALE_ITEM(2070, 0, 0),
+	0x2, 0x2, TLV_DB_SCALE_ITEM(2350, 0, 0),
+	0x3, 0x3, TLV_DB_SCALE_ITEM(2630, 0, 0),
+);
+
+/*
+ * DAC digital volumes. From -103.5 to 24 dB in 0.5 dB steps. Note that
+ * setting the gain below -100 dB (register value <0x7) is effectively a MUTE
+ * as per device datasheet.
+ */
+static DECLARE_TLV_DB_SCALE(dac_tlv, -10350, 50, 0);
+
+static const struct snd_kcontrol_new tas5720_snd_controls[] = {
+	SOC_SINGLE_TLV("Speaker Driver Playback Volume",
+		       TAS5720_VOLUME_CTRL_REG, 0, 0xff, 0, dac_tlv),
+	SOC_SINGLE_TLV("Speaker Driver Analog Gain", TAS5720_ANALOG_CTRL_REG,
+		       TAS5720_ANALOG_GAIN_SHIFT, 3, 0, dac_analog_tlv),
+};
+
+static const struct snd_soc_dapm_widget tas5720_dapm_widgets[] = {
+	SND_SOC_DAPM_AIF_IN("DAC IN", "Playback", 0, SND_SOC_NOPM, 0, 0),
+	SND_SOC_DAPM_DAC("DAC", NULL, SND_SOC_NOPM, 0, 0),
+
+	/* Events used to control the TAS5720 SHUTDOWN state */
+	SND_SOC_DAPM_PRE("Pre Event", tas5720_dapm_pre_event),
+	SND_SOC_DAPM_POST("Post Event", tas5720_dapm_post_event),
+
+	SND_SOC_DAPM_OUTPUT("OUT")
+};
+
+static const struct snd_soc_dapm_route tas5720_audio_map[] = {
+	{ "OUT", NULL, "DAC IN" },
+};
+
+static struct snd_soc_codec_driver soc_codec_dev_tas5720 = {
+	.probe = tas5720_codec_probe,
+	.remove = tas5720_codec_remove,
+	.suspend = tas5720_suspend,
+	.resume = tas5720_resume,
+
+	.controls = tas5720_snd_controls,
+	.num_controls = ARRAY_SIZE(tas5720_snd_controls),
+	.dapm_widgets = tas5720_dapm_widgets,
+	.num_dapm_widgets = ARRAY_SIZE(tas5720_dapm_widgets),
+	.dapm_routes = tas5720_audio_map,
+	.num_dapm_routes = ARRAY_SIZE(tas5720_audio_map),
+};
+
+/* PCM rates supported by the TAS5720 driver */
+#define TAS5720_RATES	(SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000 |\
+			 SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000)
+
+/* Formats supported by TAS5720 driver */
+#define TAS5720_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S18_3LE |\
+			 SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_S24_LE)
+
+static struct snd_soc_dai_ops tas5720_speaker_dai_ops = {
+	.hw_params	= tas5720_hw_params,
+	.set_sysclk	= tas5720_set_dai_sysclk,
+	.set_fmt	= tas5720_set_dai_fmt,
+	.set_tdm_slot	= tas5720_set_dai_tdm_slot,
+	.digital_mute	= tas5720_mute,
+};
+
+/*
+ * TAS5720 DAI structure
+ *
+ * Note that were are advertising .playback.channels_max = 2 despite this being
+ * a mono amplifier. The reason for that is that some serial ports such as TI's
+ * McASP module have a minimum number of channels (2) that they can output.
+ * Advertising more channels than we have will allow us to interface with such
+ * a serial port without really any negative side effects as the TAS5720 will
+ * simply ignore any extra channel(s) asides from the one channel that is
+ * configured to be played back.
+ */
+static struct snd_soc_dai_driver tas5720_dai[] = {
+	{
+		.name = "tas5720-amplifier",
+		.playback = {
+			.stream_name = "Playback",
+			.channels_min = 1,
+			.channels_max = 2,
+			.rates = TAS5720_RATES,
+			.formats = TAS5720_FORMATS,
+		},
+		.ops = &tas5720_speaker_dai_ops,
+	},
+};
+
+static int tas5720_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct tas5720_data *data;
+	int ret;
+	int i;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (data == NULL)
+		return -ENOMEM;
+
+	data->tas5720_client = client;
+	data->regmap = devm_regmap_init_i2c(client, &tas5720_regmap_config);
+	if (IS_ERR(data->regmap)) {
+		ret = PTR_ERR(data->regmap);
+		dev_err(dev, "failed to allocate register map: %d\n", ret);
+		return ret;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(data->supplies); i++)
+		data->supplies[i].supply = tas5720_supply_names[i];
+
+	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->supplies),
+				      data->supplies);
+	if (ret != 0) {
+		dev_err(dev, "failed to request supplies: %d\n", ret);
+		return ret;
+	}
+
+	dev_set_drvdata(dev, data);
+
+	ret = snd_soc_register_codec(&client->dev,
+				     &soc_codec_dev_tas5720,
+				     tas5720_dai, ARRAY_SIZE(tas5720_dai));
+	if (ret < 0) {
+		dev_err(dev, "failed to register codec: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int tas5720_remove(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+
+	snd_soc_unregister_codec(dev);
+
+	return 0;
+}
+
+static const struct i2c_device_id tas5720_id[] = {
+	{ "tas5720", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, tas5720_id);
+
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id tas5720_of_match[] = {
+	{ .compatible = "ti,tas5720", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, tas5720_of_match);
+#endif
+
+static struct i2c_driver tas5720_i2c_driver = {
+	.driver = {
+		.name = "tas5720",
+		.owner = THIS_MODULE,
+		.of_match_table = of_match_ptr(tas5720_of_match),
+	},
+	.probe = tas5720_probe,
+	.remove = tas5720_remove,
+	.id_table = tas5720_id,
+};
+
+module_i2c_driver(tas5720_i2c_driver);
+
+MODULE_AUTHOR("Andreas Dannenberg <dannenberg@ti.com>");
+MODULE_DESCRIPTION("TAS5720 Audio amplifier driver");
+MODULE_LICENSE("GPL");
diff --git a/sound/soc/codecs/tas5720.h b/sound/soc/codecs/tas5720.h
new file mode 100644
index 0000000..3d077c7
--- /dev/null
+++ b/sound/soc/codecs/tas5720.h
@@ -0,0 +1,90 @@ 
+/*
+ * tas5720.h - ALSA SoC Texas Instruments TAS5720 Mono Audio Amplifier
+ *
+ * Copyright (C)2015-2016 Texas Instruments Incorporated -  http://www.ti.com
+ *
+ * Author: Andreas Dannenberg <dannenberg@ti.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.
+ */
+
+#ifndef __TAS5720_H__
+#define __TAS5720_H__
+
+/* Register Address Map */
+#define TAS5720_DEVICE_ID_REG		0x00
+#define TAS5720_POWER_CTRL_REG		0x01
+#define TAS5720_DIGITAL_CTRL1_REG	0x02
+#define TAS5720_DIGITAL_CTRL2_REG	0x03
+#define TAS5720_VOLUME_CTRL_REG		0x04
+#define TAS5720_ANALOG_CTRL_REG		0x06
+#define TAS5720_FAULT_REG		0x08
+#define TAS5720_DIGITAL_CLIP2_REG	0x10
+#define TAS5720_DIGITAL_CLIP1_REG	0x11
+#define TAS5720_MAX_REG			TAS5720_DIGITAL_CLIP1_REG
+
+/* TAS5720_DEVICE_ID_REG */
+#define TAS5720_DEVICE_ID		0x01
+
+/* TAS5720_POWER_CTRL_REG */
+#define TAS5720_DIG_CLIP_MASK		GENMASK(7, 2)
+#define TAS5720_SLEEP			BIT(1)
+#define TAS5720_SDZ			BIT(0)
+
+/* TAS5720_DIGITAL_CTRL1_REG */
+#define TAS5720_HPF_BYPASS		BIT(7)
+#define TAS5720_TDM_CFG_SRC		BIT(6)
+#define TAS5720_SSZ_DS			BIT(3)
+#define TAS5720_SAIF_RIGHTJ_24BIT	(0x0)
+#define TAS5720_SAIF_RIGHTJ_20BIT	(0x1)
+#define TAS5720_SAIF_RIGHTJ_18BIT	(0x2)
+#define TAS5720_SAIF_RIGHTJ_16BIT	(0x3)
+#define TAS5720_SAIF_I2S		(0x4)
+#define TAS5720_SAIF_LEFTJ		(0x5)
+#define TAS5720_SAIF_FORMAT_MASK	GENMASK(2, 0)
+
+/* TAS5720_DIGITAL_CTRL2_REG */
+#define TAS5720_MUTE			BIT(4)
+#define TAS5720_TDM_SLOT_SEL_MASK	GENMASK(2, 0)
+
+/* TAS5720_ANALOG_CTRL_REG */
+#define TAS5720_PWM_RATE_6_3_FSYNC	(0x0 << 4)
+#define TAS5720_PWM_RATE_8_4_FSYNC	(0x1 << 4)
+#define TAS5720_PWM_RATE_10_5_FSYNC	(0x2 << 4)
+#define TAS5720_PWM_RATE_12_6_FSYNC	(0x3 << 4)
+#define TAS5720_PWM_RATE_14_7_FSYNC	(0x4 << 4)
+#define TAS5720_PWM_RATE_16_8_FSYNC	(0x5 << 4)
+#define TAS5720_PWM_RATE_20_10_FSYNC	(0x6 << 4)
+#define TAS5720_PWM_RATE_24_12_FSYNC	(0x7 << 4)
+#define TAS5720_PWM_RATE_MASK		GENMASK(6, 4)
+#define TAS5720_ANALOG_GAIN_19_2DBV	(0x0 << 2)
+#define TAS5720_ANALOG_GAIN_20_7DBV	(0x1 << 2)
+#define TAS5720_ANALOG_GAIN_23_5DBV	(0x2 << 2)
+#define TAS5720_ANALOG_GAIN_26_3DBV	(0x3 << 2)
+#define TAS5720_ANALOG_GAIN_MASK	GENMASK(3, 2)
+#define TAS5720_ANALOG_GAIN_SHIFT	(0x2)
+
+/* TAS5720_FAULT_REG */
+#define TAS5720_OC_THRESH_100PCT	(0x0 << 4)
+#define TAS5720_OC_THRESH_75PCT		(0x1 << 4)
+#define TAS5720_OC_THRESH_50PCT		(0x2 << 4)
+#define TAS5720_OC_THRESH_25PCT		(0x3 << 4)
+#define TAS5720_OC_THRESH_MASK		GENMASK(5, 4)
+#define TAS5720_CLKE			BIT(3)
+#define TAS5720_OCE			BIT(2)
+#define TAS5720_DCE			BIT(1)
+#define TAS5720_OTE			BIT(0)
+#define TAS5720_FAULT_MASK		GENMASK(3, 0)
+
+/* TAS5720_DIGITAL_CLIP1_REG */
+#define TAS5720_CLIP1_MASK		GENMASK(7, 2)
+#define TAS5720_CLIP1_SHIFT		(0x2)
+
+#endif /* __TAS5720_H__ */