Re: [PATCH v1 2/2] ASoC: tegra: Unify ASoC machine drivers

[Rob Herring]

On Tue, May 18, 2021 at 03:13:56AM +0300, Dmitry Osipenko wrote:
> Squash all machine drivers into a single-universal one. This reduces
> code duplication, eases addition of a new drivers and upgrades older
> code to a modern Linux kernel APIs.

Nice, I never understood why each codec needed it's own machine driver 
(and typically in turn compatible string).

>
> Suggested-by: Jonathan Hunter <jonathanh@xxxxxxxxxx>
> Co-developed-by: Ion Agorria <ion@xxxxxxxxxxx>
> Signed-off-by: Ion Agorria <ion@xxxxxxxxxxx>
> Co-developed-by: Svyatoslav Ryhel <clamor95@xxxxxxxxx>
> Signed-off-by: Svyatoslav Ryhel <clamor95@xxxxxxxxx>
> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
> ---

[...]

> diff --git a/sound/soc/tegra/tegra_wm8903.c b/sound/soc/tegra/tegra_wm8903.c
> index e4863fa37b0c..fdf74bfd728e 100644
> --- a/sound/soc/tegra/tegra_wm8903.c
> +++ b/sound/soc/tegra/tegra_wm8903.c
> @@ -14,192 +14,80 @@
>   *         graeme.gregory@xxxxxxxxxxxxxxxx or linux@xxxxxxxxxxxxxxxx
>   */
>  
> +#include <linux/gpio/consumer.h>
> +#include <linux/of.h>
>  #include <linux/module.h>
>  #include <linux/platform_device.h>
> -#include <linux/slab.h>
> -#include <linux/gpio.h>
> -#include <linux/of_gpio.h>
>  
>  #include <sound/core.h>
>  #include <sound/jack.h>
> -#include <sound/pcm.h>
> -#include <sound/pcm_params.h>
>  #include <sound/soc.h>
>  
>  #include "../codecs/wm8903.h"
>  
> -#include "tegra_asoc_utils.h"
> +#include "tegra_asoc_machine.h"
>  
> -#define DRV_NAME "tegra-snd-wm8903"
> +static struct snd_soc_jack_pin tegra_wm8903_mic_jack_pins[] = {
> +	{ .pin = "Mic Jack", .mask = SND_JACK_MICROPHONE },
> +};
>  
> -struct tegra_wm8903 {
> -	int gpio_spkr_en;
> -	int gpio_hp_det;
> -	int gpio_hp_mute;
> -	int gpio_int_mic_en;
> -	int gpio_ext_mic_en;
> -	struct tegra_asoc_utils_data util_data;
> +static const char * const tegra_active_low_hp_compats[] = {
> +	"ad,tegra-audio-plutux",
> +	"ad,tegra-audio-wm8903-medcom-wide",
> +	"ad,tegra-audio-wm8903-tec",
> +	"nvidia,tegra-audio-wm8903-cardhu",
> +	"nvidia,tegra-audio-wm8903-harmony",
> +	"nvidia,tegra-audio-wm8903-picasso",
> +	"nvidia,tegra-audio-wm8903-seaboard",
> +	"nvidia,tegra-audio-wm8903-ventana",
> +	NULL,

I think this list should be added to the main match table below with 
data having a flag for active low HP. Then you only match once, don't 
need the exported function and the next difference is much easier to 
add.

>  };
>  
> -static int tegra_wm8903_hw_params(struct snd_pcm_substream *substream,
> -					struct snd_pcm_hw_params *params)
> +static int tegra_wm8903_init(struct snd_soc_pcm_runtime *rtd)
>  {
> -	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
> -	struct snd_soc_dai *codec_dai = asoc_rtd_to_codec(rtd, 0);
> +	struct tegra_machine *machine = snd_soc_card_get_drvdata(rtd->card);
> +	struct device_node *np = rtd->card->dev->of_node;
>  	struct snd_soc_card *card = rtd->card;
> -	struct tegra_wm8903 *machine = snd_soc_card_get_drvdata(card);
> -	int srate, mclk;
>  	int err;
>  
> -	srate = params_rate(params);
> -	switch (srate) {
> -	case 64000:
> -	case 88200:
> -	case 96000:
> -		mclk = 128 * srate;
> -		break;
> -	default:
> -		mclk = 256 * srate;
> -		break;
> -	}
> -	/* FIXME: Codec only requires >= 3MHz if OSR==0 */
> -	while (mclk < 6000000)
> -		mclk *= 2;
> +	/*
> +	 * Older version of machine driver was ignoring GPIO polarity,
> +	 * forcing it to active-low.  This means that all older device-trees
> +	 * which set the polarity to active-high are wrong and we need to fix
> +	 * up them.
> +	 */
> +	if (of_device_compatible_match(np, tegra_active_low_hp_compats)) {
> +		bool active_low = gpiod_is_active_low(machine->gpiod_hp_det);

[...]

> +static const struct tegra_asoc_data tegra_wm8903_data = {
> +	.mclk_rate = tegra_asoc_machine_mclk_rate,
> +	.card = &snd_soc_tegra_wm8903,
> +	.add_common_dapm_widgets = true,
> +	.add_common_controls = true,
> +	.add_common_soc_ops = true,
> +	.add_mic_jack = true,
> +	.add_hp_jack = true,
> +};
>  
>  static const struct of_device_id tegra_wm8903_of_match[] = {
> -	{ .compatible = "nvidia,tegra-audio-wm8903", },
> +	{ .compatible = "nvidia,tegra-audio-wm8903", .data = &tegra_wm8903_data },
>  	{},
>  };
> +MODULE_DEVICE_TABLE(of, tegra_wm8903_of_match);
>  
>  static struct platform_driver tegra_wm8903_driver = {
>  	.driver = {
> -		.name = DRV_NAME,
> -		.pm = &snd_soc_pm_ops,
> +		.name = "tegra-wm8903",
>  		.of_match_table = tegra_wm8903_of_match,
> +		.pm = &snd_soc_pm_ops,
>  	},
> -	.probe = tegra_wm8903_driver_probe,
> +	.probe = tegra_asoc_machine_probe,
>  };
>  module_platform_driver(tegra_wm8903_driver);
>  
>  MODULE_AUTHOR("Stephen Warren <swarren@xxxxxxxxxx>");
>  MODULE_DESCRIPTION("Tegra+WM8903 machine ASoC driver");
>  MODULE_LICENSE("GPL");
> -MODULE_ALIAS("platform:" DRV_NAME);
> -MODULE_DEVICE_TABLE(of, tegra_wm8903_of_match);