sound/soc/codecs/max98357a.c

Source file repositories/reference/linux-study-clean/sound/soc/codecs/max98357a.c

File Facts

System
Linux kernel
Corpus path
sound/soc/codecs/max98357a.c
Extension
.c
Size
4791 bytes
Lines
183
Domain
Driver Families
Bucket
sound/soc
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct max98357a_priv {
	struct gpio_desc *sdmode;
	unsigned int sdmode_delay;
	int sdmode_switch;
};

static int max98357a_daiops_trigger(struct snd_pcm_substream *substream,
		int cmd, struct snd_soc_dai *dai)
{
	struct snd_soc_component *component = dai->component;
	struct max98357a_priv *max98357a =
		snd_soc_component_get_drvdata(component);

	if (!max98357a->sdmode)
		return 0;

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
		mdelay(max98357a->sdmode_delay);
		if (max98357a->sdmode_switch) {
			gpiod_set_value(max98357a->sdmode, 1);
			dev_dbg(component->dev, "set sdmode to 1");
		}
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
		gpiod_set_value(max98357a->sdmode, 0);
		dev_dbg(component->dev, "set sdmode to 0");
		break;
	}

	return 0;
}

static int max98357a_sdmode_event(struct snd_soc_dapm_widget *w,
		struct snd_kcontrol *kcontrol, int event)
{
	struct snd_soc_component *component =
		snd_soc_dapm_to_component(w->dapm);
	struct max98357a_priv *max98357a =
		snd_soc_component_get_drvdata(component);

	if (event & SND_SOC_DAPM_POST_PMU)
		max98357a->sdmode_switch = 1;
	else if (event & SND_SOC_DAPM_POST_PMD)
		max98357a->sdmode_switch = 0;

	return 0;
}

static const struct snd_soc_dapm_widget max98357a_dapm_widgets[] = {
	SND_SOC_DAPM_OUTPUT("Speaker"),
	SND_SOC_DAPM_OUT_DRV_E("SD_MODE", SND_SOC_NOPM, 0, 0, NULL, 0,
			max98357a_sdmode_event,
			SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_POST_PMD),
};

static const struct snd_soc_dapm_route max98357a_dapm_routes[] = {
	{"SD_MODE", NULL, "HiFi Playback"},
	{"Speaker", NULL, "SD_MODE"},
};

static const struct snd_soc_component_driver max98357a_component_driver = {
	.dapm_widgets		= max98357a_dapm_widgets,
	.num_dapm_widgets	= ARRAY_SIZE(max98357a_dapm_widgets),
	.dapm_routes		= max98357a_dapm_routes,
	.num_dapm_routes	= ARRAY_SIZE(max98357a_dapm_routes),
	.idle_bias_on		= 1,
	.use_pmdown_time	= 1,
	.endianness		= 1,
};

static const struct snd_soc_dai_ops max98357a_dai_ops = {
	.trigger        = max98357a_daiops_trigger,
};

static struct snd_soc_dai_driver max98357a_dai_driver = {
	.name = "HiFi",
	.playback = {
		.stream_name	= "HiFi Playback",
		.formats	= SNDRV_PCM_FMTBIT_S16 |
					SNDRV_PCM_FMTBIT_S24 |
					SNDRV_PCM_FMTBIT_S32,
		.rates		= SNDRV_PCM_RATE_8000 |
					SNDRV_PCM_RATE_16000 |
					SNDRV_PCM_RATE_32000 |
					SNDRV_PCM_RATE_44100 |

Annotation

Implementation Notes