[alsa-devel] [PATCH] ASoC: Add PCM1681 codec driver.

Daniel Mack zonque at gmail.com
Wed Jun 26 15:55:56 CEST 2013


On 26.06.2013 15:46, Marek Belisko wrote:
> Hi Daniel,
> On 06/26/2013 03:16 PM, Daniel Mack wrote:
>> Hi Marek,
>>
>> On 26.06.2013 15:05, Marek Belisko wrote:
>>> PCM1681 can be controlled via I2C, SPI or in bootstrap mode. This code add
>>> support only for I2C mode.
>>>
>>> Signed-off-by: Marek Belisko <marek.belisko at streamunlimited.com>
>>> ---
>>>   .../devicetree/bindings/sound/ti,pcm1681.txt       |   15 +
>>>   sound/soc/codecs/Kconfig                           |    4 +
>>>   sound/soc/codecs/Makefile                          |    2 +
>>>   sound/soc/codecs/pcm1681.c                         |  328 ++++++++++++++++++++
>>>   4 files changed, 349 insertions(+)
>>>   create mode 100644 Documentation/devicetree/bindings/sound/ti,pcm1681.txt
>>>   create mode 100644 sound/soc/codecs/pcm1681.c
>>>
>>> diff --git a/Documentation/devicetree/bindings/sound/ti,pcm1681.txt b/Documentation/devicetree/bindings/sound/ti,pcm1681.txt
>>> new file mode 100644
>>> index 0000000..4df1718
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/sound/ti,pcm1681.txt
>>> @@ -0,0 +1,15 @@
>>> +Texas Instruments PCM1681 8-channel PWM Processor
>>> +
>>> +Required properties:
>>> +
>>> + - compatible:		Should contain "ti,pcm1681".
>>> + - reg:			The i2c address. Should contain <0x4c>.
>>> +
>>> +Examples:
>>> +
>>> +	i2c_bus {
>>> +		pcm1681 at 4c {
>>> +			compatible = "ti,pcm1681";
>>> +			reg = <0x4c>;
>>> +		};
>>> +	};
>>> diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
>>> index badb6fb..e2daf82 100644
>>> --- a/sound/soc/codecs/Kconfig
>>> +++ b/sound/soc/codecs/Kconfig
>>> @@ -54,6 +54,7 @@ config SND_SOC_ALL_CODECS
>>>   	select SND_SOC_MC13783 if MFD_MC13XXX
>>>   	select SND_SOC_ML26124 if I2C
>>>   	select SND_SOC_HDMI_CODEC
>>> +	select SND_SOC_PCM1681 if I2C
>>>   	select SND_SOC_PCM3008
>>>   	select SND_SOC_RT5631 if I2C
>>>   	select SND_SOC_RT5640 if I2C
>>> @@ -292,6 +293,9 @@ config SND_SOC_MAX9850
>>>   config SND_SOC_HDMI_CODEC
>>>          tristate
>>>
>>> +config SND_SOC_PCM1681
>>> +       tristate
>>> +
>>>   config SND_SOC_PCM3008
>>>          tristate
>>>
>>> diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile
>>> index 70fd806..4a068d2 100644
>>> --- a/sound/soc/codecs/Makefile
>>> +++ b/sound/soc/codecs/Makefile
>>> @@ -42,6 +42,7 @@ snd-soc-max9850-objs := max9850.o
>>>   snd-soc-mc13783-objs := mc13783.o
>>>   snd-soc-ml26124-objs := ml26124.o
>>>   snd-soc-hdmi-codec-objs := hdmi.o
>>> +snd-soc-pcm1681-objs := pcm1681.o
>>>   snd-soc-pcm3008-objs := pcm3008.o
>>>   snd-soc-rt5631-objs := rt5631.o
>>>   snd-soc-rt5640-objs := rt5640.o
>>> @@ -171,6 +172,7 @@ obj-$(CONFIG_SND_SOC_MAX9850)	+= snd-soc-max9850.o
>>>   obj-$(CONFIG_SND_SOC_MC13783)	+= snd-soc-mc13783.o
>>>   obj-$(CONFIG_SND_SOC_ML26124)	+= snd-soc-ml26124.o
>>>   obj-$(CONFIG_SND_SOC_HDMI_CODEC) += snd-soc-hdmi-codec.o
>>> +obj-$(CONFIG_SND_SOC_PCM1681)	+= snd-soc-pcm1681.o
>>>   obj-$(CONFIG_SND_SOC_PCM3008)	+= snd-soc-pcm3008.o
>>>   obj-$(CONFIG_SND_SOC_RT5631)	+= snd-soc-rt5631.o
>>>   obj-$(CONFIG_SND_SOC_RT5640)	+= snd-soc-rt5640.o
>>> diff --git a/sound/soc/codecs/pcm1681.c b/sound/soc/codecs/pcm1681.c
>>> new file mode 100644
>>> index 0000000..6122fd1
>>> --- /dev/null
>>> +++ b/sound/soc/codecs/pcm1681.c
>>> @@ -0,0 +1,328 @@
>>> +/*
>>> + * PCM1681 ASoC codec driver
>>> + *
>>> + * Copyright (c) StreamUnlimited GmbH 2013
>>> + *	Marek Belisko <marek.belisko at streamunlimited.com>
>>> + *
>>> + * 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.
>>> + *
>>> + * 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/slab.h>
>>> +#include <linux/delay.h>
>>> +#include <linux/gpio.h>
>>> +#include <linux/i2c.h>
>>> +#include <linux/regmap.h>
>>> +#include <linux/of_device.h>
>>> +#include <linux/of_gpio.h>
>>> +#include <sound/pcm.h>
>>> +#include <sound/pcm_params.h>
>>> +#include <sound/soc.h>
>>> +#include <sound/tlv.h>
>>> +
>>> +#define PCM1681_PCM_FORMATS (SNDRV_PCM_FMTBIT_S16_LE  |		\
>>> +			     SNDRV_PCM_FMTBIT_S24_LE)
>>> +
>>> +#define PCM1681_PCM_RATES   (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_16000 | \
>>> +			     SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100  | \
>>> +			     SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_88200  | \
>>> +			     SNDRV_PCM_RATE_96000 | SNDRV_PCM_RATE_192000)
>>> +
>>> +#define PCM1681_SOFT_MUTE_ALL		0xff
>>> +#define PCM1681_DEEMPH_RATE_MASK	0x18
>>> +#define PCM1681_DEEMPH_MASK		0x01
>>> +
>>> +#define PCM1681_ATT_CONTROL(X)	(X <= 6 ? X : X + 9) /* Attenuation level */
>>> +#define PCM1681_SOFT_MUTE	0x07	/* Soft mute control register */
>>> +#define PCM1681_DAC_CONTROL	0x08	/* DAC operation control */
>>> +#define PCM1681_FMT_CONTROL	0x09	/* Audio interface data format */
>>> +#define PCM1681_DEEMPH_CONTROL	0x0a	/* De-emphasis control */
>>> +#define PCM1681_ZERO_DETECT_STATUS	0x0e	/* Zero detect status reg */
>>> +
>>> +static const struct reg_default pcm1681_reg_defaults[] = {
>>> +	{ 0x01,	0xff },
>>> +	{ 0x02,	0xff },
>>> +	{ 0x03,	0xff },
>>> +	{ 0x04,	0xff },
>>> +	{ 0x05,	0xff },
>>> +	{ 0x06,	0xff },
>>> +	{ 0x07,	0x00 },
>>> +	{ 0x08,	0x00 },
>>> +	{ 0x09,	0x06 },
>>> +	{ 0x0A,	0x00 },
>>> +	{ 0x0B,	0xff },
>>> +	{ 0x0C,	0x0f },
>>> +	{ 0x0D,	0x00 },
>>> +	{ 0x10,	0xff },
>>> +	{ 0x11,	0xff },
>>> +	{ 0x12,	0x00 },
>>> +	{ 0x13,	0x00 },
>>> +};
>>> +
>>> +static bool pcm1681_accessible_reg(struct device *dev, unsigned int reg)
>>> +{
>>> +	return !((reg == 0x00) || (reg == 0x0f));
>>> +}
>>> +
>>> +static bool pcm1681_writeable_reg(struct device *dev, unsigned register reg)
>>> +{
>>> +	return pcm1681_accessible_reg(dev, reg) &&
>>> +		(reg != PCM1681_ZERO_DETECT_STATUS);
>>> +}
>>> +
>>> +struct pcm1681_private {
>>> +	struct regmap *regmap;
>>> +	unsigned int format;
>>> +	/* Current deemphasis status */
>>> +	unsigned int deemph;
>>> +	/* Current rate for deemphasis control */
>>> +	unsigned int rate;
>>> +};
>>> +
>>> +static int pcm1681_deemph[] = { 44100, 48000, 32000 };
>>> +
>>> +static int pcm1681_set_deemph(struct snd_soc_codec *codec)
>>> +{
>>> +	struct pcm1681_private *priv = snd_soc_codec_get_drvdata(codec);
>>> +	int i = 0, val = -1, ret;
>>> +
>>> +	if (priv->deemph)
>>> +		for (i = 0; i < ARRAY_SIZE(pcm1681_deemph); i++)
>>> +			if (pcm1681_deemph[i] == priv->rate)
>>> +				val = i;
>>> +
>>> +	/* enable choosen frequency */
>>> +	if (val != -1)
>>> +		regmap_update_bits(priv->regmap, PCM1681_DEEMPH_CONTROL,
>>> +					PCM1681_DEEMPH_RATE_MASK, val);
>>> +
>>> +	/* enable/disable deemphasis functionality */
>>> +	ret = regmap_update_bits(priv->regmap, PCM1681_DEEMPH_CONTROL,
>>> +				PCM1681_DEEMPH_MASK, priv->deemph);
>>> +
>>> +	return ret;
>>> +}
>>> +
>>> +static int pcm1681_get_deemph(struct snd_kcontrol *kcontrol,
>>> +			      struct snd_ctl_elem_value *ucontrol)
>>> +{
>>> +	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
>>> +	struct pcm1681_private *priv = snd_soc_codec_get_drvdata(codec);
>>> +
>>> +	ucontrol->value.enumerated.item[0] = priv->deemph;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int pcm1681_put_deemph(struct snd_kcontrol *kcontrol,
>>> +			      struct snd_ctl_elem_value *ucontrol)
>>> +{
>>> +	struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
>>> +	struct pcm1681_private *priv = snd_soc_codec_get_drvdata(codec);
>>> +
>>> +	priv->deemph = ucontrol->value.enumerated.item[0];
>>> +
>>> +	return pcm1681_set_deemph(codec);
>>> +}
>>> +
>>> +static int pcm1681_set_dai_fmt(struct snd_soc_dai *codec_dai,
>>> +			      unsigned int format)
>>> +{
>>> +	struct snd_soc_codec *codec = codec_dai->codec;
>>> +	struct pcm1681_private *priv = snd_soc_codec_get_drvdata(codec);
>>> +
>>> +	/* The PCM1681 can only be slave to all clocks */
>>> +	if ((format & SND_SOC_DAIFMT_MASTER_MASK) != SND_SOC_DAIFMT_CBS_CFS) {
>>> +		dev_err(codec->dev, "Invalid clocking mode\n");
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	priv->format = format;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int pcm1681_digital_mute(struct snd_soc_dai *dai, int mute)
>>> +{
>>> +	struct snd_soc_codec *codec = dai->codec;
>>> +	struct pcm1681_private *priv = snd_soc_codec_get_drvdata(codec);
>>> +	int ret, val = 0;
>>> +
>>> +	if (mute)
>>> +		val = PCM1681_SOFT_MUTE_ALL;
>>> +
>>> +	ret = regmap_write(priv->regmap, PCM1681_SOFT_MUTE, val);
>>> +	if (ret < 0)
>>> +		return ret;
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static int pcm1681_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;
>>> +	struct pcm1681_private *priv = snd_soc_codec_get_drvdata(codec);
>>> +	int val = 0;
>>> +	int pcm_format = params_format(params);
>>> +
>>> +	priv->rate = params_rate(params);
>>> +
>>> +	switch (priv->format & SND_SOC_DAIFMT_FORMAT_MASK) {
>>> +	case SND_SOC_DAIFMT_RIGHT_J:
>>> +		if (pcm_format == SNDRV_PCM_FORMAT_S24_LE)
>>> +			val = 0x00;
>>> +		else if (pcm_format == SNDRV_PCM_FORMAT_S16_LE)
>>> +			val = 0x03;
>>> +		break;
>>> +	case SND_SOC_DAIFMT_I2S:
>>> +		val = 0x04;
>>> +		break;
>>> +	case SND_SOC_DAIFMT_LEFT_J:
>>> +		val = 0x05;
>>> +		break;
>>> +	default:
>>> +		dev_err(codec->dev, "Invalid DAI format\n");
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	regmap_update_bits(priv->regmap, PCM1681_FMT_CONTROL, 0x0f, val);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static const struct snd_soc_dai_ops pcm1681_dai_ops = {
>>> +	.set_fmt	= pcm1681_set_dai_fmt,
>>> +	.hw_params	= pcm1681_hw_params,
>>> +	.digital_mute	= pcm1681_digital_mute,
>>> +};
>>> +
>>> +static const DECLARE_TLV_DB_SCALE(pcm1681_dac_tlv, -6350, 50, 1);
>>> +
>>> +static const struct snd_kcontrol_new pcm1681_controls[] = {
>>> +	SOC_DOUBLE_R_TLV("PCM1681 Channel 1/2 Playback Volume",
>>> +			PCM1681_ATT_CONTROL(1), PCM1681_ATT_CONTROL(2), 0,
>>> +			0x7f, 0, pcm1681_dac_tlv),
>>> +	SOC_DOUBLE_R_TLV("PCM1681 Channel 3/4 Playback Volume",
>>> +			PCM1681_ATT_CONTROL(3), PCM1681_ATT_CONTROL(4), 0,
>>> +			0x7f, 0, pcm1681_dac_tlv),
>>> +	SOC_DOUBLE_R_TLV("PCM1681 Channel 5/6 Playback Volume",
>>> +			PCM1681_ATT_CONTROL(5), PCM1681_ATT_CONTROL(6), 0,
>>> +			0x7f, 0, pcm1681_dac_tlv),
>>> +	SOC_DOUBLE_R_TLV("PCM1681 Channel 7/8 Playback Volume",
>>> +			PCM1681_ATT_CONTROL(7), PCM1681_ATT_CONTROL(8), 0,
>>> +			0x7f, 0, pcm1681_dac_tlv),
>>> +	SOC_SINGLE_BOOL_EXT("PCM1681 De-emphasis Switch", 0,
>>> +			    pcm1681_get_deemph, pcm1681_put_deemph),
>>> +};
>>> +
>>> +struct snd_soc_dai_driver pcm1681_dai = {
>>> +	.name = "pcm1681-hifi",
>>> +	.playback = {
>>> +		.stream_name = "Playback",
>>> +		.channels_min = 2,
>>> +		.channels_max = 8,
>>> +		.rates = PCM1681_PCM_RATES,
>>> +		.formats = PCM1681_PCM_FORMATS,
>>> +	},
>>> +	.ops = &pcm1681_dai_ops,
>>> +};
>>> +
>>> +#ifdef CONFIG_OF
>>> +static const struct of_device_id pcm1681_dt_ids[] = {
>>> +	{ .compatible = "ti,pcm1681", },
>>> +	{ }
>>> +};
>>> +MODULE_DEVICE_TABLE(of, pcm1681_dt_ids);
>>> +#endif
>>> +
>>> +static const struct regmap_config pcm1681_regmap = {
>>> +	.reg_bits		= 8,
>>> +	.val_bits		= 8,
>>> +	.max_register		= ARRAY_SIZE(pcm1681_reg_defaults),
>>> +	.reg_defaults		= pcm1681_reg_defaults,
>>> +	.num_reg_defaults	= ARRAY_SIZE(pcm1681_reg_defaults),
>>> +	.writeable_reg		= pcm1681_writeable_reg,
>>> +	.readable_reg		= pcm1681_accessible_reg,
>>> +};
>>> +
>>> +static int pcm1681_probe(struct snd_soc_codec *codec)
>>> +{
>>> +	return 0;
>>
>> Is there really nothing the driver has to do in order to bring the codec
>> into full operation mode?
> This codec have only POWER-ON-RESET function. It means codec need system 
> clock (normally MCLK) for some amount of time to get out of reset and 
> then you can communicate with it.
>>
>>> +}
>>> +
>>> +static int pcm1681_remove(struct snd_soc_codec *codec)
>>> +{
>>> +	return 0;
>>> +}
>>> +
>>> +static struct snd_soc_codec_driver soc_codec_dev_pcm1681 = {
>>> +	.probe			= pcm1681_probe,
>>> +	.remove			= pcm1681_remove,
>>> +	.controls		= pcm1681_controls,
>>> +	.num_controls		= ARRAY_SIZE(pcm1681_controls),
>>> +};
>>> +
>>> +#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
>>> +static const struct i2c_device_id pcm1681_i2c_id[] = {
>>> +	{"pcm1681", 0},
>>> +	{}
>>> +};
>>> +MODULE_DEVICE_TABLE(i2c, pcm1681_i2c_id);
>>> +
>>> +static int pcm1681_i2c_probe(struct i2c_client *client,
>>> +			      const struct i2c_device_id *id)
>>> +{
>>> +	int ret;
>>> +	struct pcm1681_private *priv;
>>> +
>>> +	priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
>>> +	if (!priv)
>>> +		return -ENOMEM;
>>> +
>>> +	priv->regmap = devm_regmap_init_i2c(client, &pcm1681_regmap);
>>> +	if (IS_ERR(priv->regmap)) {
>>> +		ret = PTR_ERR(priv->regmap);
>>> +		dev_err(&client->dev, "Failed to create regmap: %d\n", ret);
>>> +		return ret;
>>> +	}
>>> +
>>> +	i2c_set_clientdata(client, priv);
>>> +
>>
>> Is there any way to probe the device is there at all? I'd like to bail
>> early in case the bus or i2c address doesn't match for example.
> Probing is done here because we assume that codec is out of reset.

Yes, I know. I wondered whether there is any register that the driver
can read back in order to check the presence of the device. But I
quickly checked the datasheet, and there does in fact not seem to be
such a register.

>> Also, I wonder whether there are any reset lines that might be connected
>> to GPIOs of the MCU. If so, it would be good idea to add support for
>> that in this driver. But that can be done at some later point as well.
> No other pins which can be handled.

I see. Well ok then, I have no further remarks :)


Daniel



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