[alsa-devel] [PATCH v3 1/3] ASoC: codecs: adau1701: allow configuration of PLL mode pins

Lars-Peter Clausen lars at metafoo.de
Fri Jun 21 10:09:04 CEST 2013


On 06/21/2013 09:54 AM, Daniel Mack wrote:
> The ADAU1701 has 2 hardware pins to configure the PLL mode in accordance
> to the MCLK-to-LRCLK ratio. These pins have to be stable before the chip
> is released from reset, and a full reset cycle, including a new firmware
> download is needed whenever they change.
> 
> This patch adds GPIO properties to the DT bindings of the Codec, and
> implements makes the set_sysclk memorize the configured sysclk.
> 
> To avoid excessive reset cycles and firmware downloads, the default
> clock divider can be specified in DT as well. Whenever a ratio change is
> detected in the hw_params callback, the PLL mode lines are updates and a
> full reset cycle is issued.
> 
> Signed-off-by: Daniel Mack <zonque at gmail.com>

Acked-by: Lars-Peter Clausen <lars at metafoo.de>

Thanks.

> ---
>  .../devicetree/bindings/sound/adi,adau1701.txt     |  15 +++
>  sound/soc/codecs/adau1701.c                        | 105 ++++++++++++++++-----
>  2 files changed, 99 insertions(+), 21 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/sound/adi,adau1701.txt b/Documentation/devicetree/bindings/sound/adi,adau1701.txt
> index 3afeda7..173ae06 100644
> --- a/Documentation/devicetree/bindings/sound/adi,adau1701.txt
> +++ b/Documentation/devicetree/bindings/sound/adi,adau1701.txt
> @@ -11,6 +11,20 @@ Optional properties:
>   - reset-gpio: 		A GPIO spec to define which pin is connected to the
>  			chip's !RESET pin. If specified, the driver will
>  			assert a hardware reset at probe time.
> + - adi,pll-clkdiv: 	The PLL clock divider, specifing the ratio between
> +			MCLK and fsclk. The value is used to determine the
> +			correct state of the two mode pins below.
> +			Note that this value can be overridden at runtime
> +			by configuring the Codec in an altered MCLK/LRCLK ratio
> +			via its hwparams() call. However, the chips needs a
> +			full reset cycle and a new firmware download each time
> +			the configuration changes, hence this property can help
> +			systems provide a sane default.
> + - adi,pll-mode-gpios:	An array of two GPIO specs to describe the GPIOs
> +			the ADAU's PLL config pins are connected to.
> +			The state of the pins are set according to the
> +			configured clock divider on ASoC side before the
> +			firmware is loaded.
>  
>  Examples:
>  
> @@ -19,5 +33,6 @@ Examples:
>  			compatible = "adi,adau1701";
>  			reg = <0x34>;
>  			reset-gpio = <&gpio 23 0>;
> +			adi,pll-mode-gpios = <&gpio 24 0 &gpio 25 0>;
>  		};
>  	};
> diff --git a/sound/soc/codecs/adau1701.c b/sound/soc/codecs/adau1701.c
> index b6b1a77..6bc566f 100644
> --- a/sound/soc/codecs/adau1701.c
> +++ b/sound/soc/codecs/adau1701.c
> @@ -91,7 +91,10 @@
>  
>  struct adau1701 {
>  	int gpio_nreset;
> +	int gpio_pll_mode[2];
>  	unsigned int dai_fmt;
> +	unsigned int pll_clkdiv;
> +	unsigned int sysclk;
>  };
>  
>  static const struct snd_kcontrol_new adau1701_controls[] = {
> @@ -184,13 +187,37 @@ static unsigned int adau1701_read(struct snd_soc_codec *codec, unsigned int reg)
>  	return value;
>  }
>  
> -static void adau1701_reset(struct snd_soc_codec *codec)
> +static void adau1701_reset(struct snd_soc_codec *codec, unsigned int clkdiv)
>  {
>  	struct adau1701 *adau1701 = snd_soc_codec_get_drvdata(codec);
>  
>  	if (!gpio_is_valid(adau1701->gpio_nreset))
>  		return;
>  
> +	if (gpio_is_valid(adau1701->gpio_pll_mode[0]) &&
> +	    gpio_is_valid(adau1701->gpio_pll_mode[1])) {
> +		switch (clkdiv) {
> +		case 64:
> +			gpio_set_value(adau1701->gpio_pll_mode[0], 0);
> +			gpio_set_value(adau1701->gpio_pll_mode[1], 0);
> +			break;
> +		case 256:
> +			gpio_set_value(adau1701->gpio_pll_mode[0], 0);
> +			gpio_set_value(adau1701->gpio_pll_mode[1], 1);
> +			break;
> +		case 384:
> +			gpio_set_value(adau1701->gpio_pll_mode[0], 1);
> +			gpio_set_value(adau1701->gpio_pll_mode[1], 0);
> +			break;
> +		case 512:
> +			gpio_set_value(adau1701->gpio_pll_mode[0], 1);
> +			gpio_set_value(adau1701->gpio_pll_mode[1], 1);
> +			break;
> +		}
> +	}
> +
> +	adau1701->pll_clkdiv = clkdiv;
> +
>  	gpio_set_value(adau1701->gpio_nreset, 0);
>  	/* minimum reset time is 20ns */
>  	udelay(1);
> @@ -199,24 +226,6 @@ static void adau1701_reset(struct snd_soc_codec *codec)
>  	mdelay(85);
>  }
>  
> -static int adau1701_init(struct snd_soc_codec *codec)
> -{
> -	int ret;
> -	struct i2c_client *client = to_i2c_client(codec->dev);
> -
> -	adau1701_reset(codec);
> -
> -	ret = process_sigma_firmware(client, ADAU1701_FIRMWARE);
> -	if (ret) {
> -		dev_warn(codec->dev, "Failed to load firmware\n");
> -		return ret;
> -	}
> -
> -	snd_soc_write(codec, ADAU1701_DACSET, ADAU1701_DACSET_DACINIT);
> -
> -	return 0;
> -}
> -
>  static int adau1701_set_capture_pcm_format(struct snd_soc_codec *codec,
>  		snd_pcm_format_t format)
>  {
> @@ -291,9 +300,22 @@ static int adau1701_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 adau1701 *adau1701 = snd_soc_codec_get_drvdata(codec);
>  	snd_pcm_format_t format;
>  	unsigned int val;
>  
> +	if (adau1701->sysclk) {
> +		unsigned int clkdiv = adau1701->sysclk / params_rate(params);
> +
> +		/*
> +		 * If the mclk/lrclk ratio changes, the chip needs updated PLL
> +		 * mode GPIO settings, and a full reset cycle, including a new
> +		 * firmware upload.
> +		 */
> +		if (clkdiv != adau1701->pll_clkdiv)
> +			adau1701_reset(codec, clkdiv);
> +	}
> +
>  	switch (params_rate(params)) {
>  	case 192000:
>  		val = ADAU1701_DSPCTRL_SR_192;
> @@ -435,6 +457,7 @@ static int adau1701_set_sysclk(struct snd_soc_codec *codec, int clk_id,
>  	int source, unsigned int freq, int dir)
>  {
>  	unsigned int val;
> +	struct adau1701 *adau1701 = snd_soc_codec_get_drvdata(codec);
>  
>  	switch (clk_id) {
>  	case ADAU1701_CLK_SRC_OSC:
> @@ -448,6 +471,7 @@ static int adau1701_set_sysclk(struct snd_soc_codec *codec, int clk_id,
>  	}
>  
>  	snd_soc_update_bits(codec, ADAU1701_OSCIPOW, ADAU1701_OSCIPOW_OPD, val);
> +	adau1701->sysclk = freq;
>  
>  	return 0;
>  }
> @@ -495,13 +519,21 @@ MODULE_DEVICE_TABLE(of, adau1701_dt_ids);
>  static int adau1701_probe(struct snd_soc_codec *codec)
>  {
>  	int ret;
> +	struct i2c_client *client = to_i2c_client(codec->dev);
> +	struct adau1701 *adau1701 = snd_soc_codec_get_drvdata(codec);
>  
>  	codec->control_data = to_i2c_client(codec->dev);
>  
> -	ret = adau1701_init(codec);
> -	if (ret)
> +	/* initalize with pre-configured pll mode settings */
> +	adau1701_reset(codec, adau1701->pll_clkdiv);
> +
> +	ret = process_sigma_firmware(client, ADAU1701_FIRMWARE);
> +	if (ret) {
> +		dev_warn(codec->dev, "Failed to load firmware\n");
>  		return ret;
> +	}
>  
> +	snd_soc_write(codec, ADAU1701_DACSET, ADAU1701_DACSET_DACINIT);
>  	snd_soc_write(codec, ADAU1701_DSPCTRL, ADAU1701_DSPCTRL_CR);
>  
>  	return 0;
> @@ -534,6 +566,7 @@ static int adau1701_i2c_probe(struct i2c_client *client,
>  	struct adau1701 *adau1701;
>  	struct device *dev = &client->dev;
>  	int gpio_nreset = -EINVAL;
> +	int gpio_pll_mode[2] = { -EINVAL, -EINVAL };
>  	int ret;
>  
>  	adau1701 = devm_kzalloc(dev, sizeof(*adau1701), GFP_KERNEL);
> @@ -544,6 +577,19 @@ static int adau1701_i2c_probe(struct i2c_client *client,
>  		gpio_nreset = of_get_named_gpio(dev->of_node, "reset-gpio", 0);
>  		if (gpio_nreset < 0 && gpio_nreset != -ENOENT)
>  			return gpio_nreset;
> +
> +		gpio_pll_mode[0] = of_get_named_gpio(dev->of_node,
> +						   "adi,pll-mode-gpios", 0);
> +		if (gpio_pll_mode[0] < 0 && gpio_pll_mode[0] != -ENOENT)
> +			return gpio_pll_mode[0];
> +
> +		gpio_pll_mode[1] = of_get_named_gpio(dev->of_node,
> +						   "adi,pll-mode-gpios", 1);
> +		if (gpio_pll_mode[1] < 0 && gpio_pll_mode[1] != -ENOENT)
> +			return gpio_pll_mode[1];
> +
> +		of_property_read_u32(dev->of_node, "adi,pll-clkdiv",
> +				     &adau1701->pll_clkdiv);
>  	}
>  
>  	if (gpio_is_valid(gpio_nreset)) {
> @@ -553,7 +599,24 @@ static int adau1701_i2c_probe(struct i2c_client *client,
>  			return ret;
>  	}
>  
> +	if (gpio_is_valid(gpio_pll_mode[0]) &&
> +	    gpio_is_valid(gpio_pll_mode[1])) {
> +		ret = devm_gpio_request_one(dev, gpio_pll_mode[0],
> +					    GPIOF_OUT_INIT_LOW,
> +					    "ADAU1701 PLL mode 0");
> +		if (ret < 0)
> +			return ret;
> +
> +		ret = devm_gpio_request_one(dev, gpio_pll_mode[1],
> +					    GPIOF_OUT_INIT_LOW,
> +					    "ADAU1701 PLL mode 1");
> +		if (ret < 0)
> +			return ret;
> +	}
> +
>  	adau1701->gpio_nreset = gpio_nreset;
> +	adau1701->gpio_pll_mode[0] = gpio_pll_mode[0];
> +	adau1701->gpio_pll_mode[1] = gpio_pll_mode[1];
>  
>  	i2c_set_clientdata(client, adau1701);
>  	ret = snd_soc_register_codec(&client->dev, &adau1701_codec_drv,



More information about the Alsa-devel mailing list