sound/soc/ti/davinci-evm.c

Source file repositories/reference/linux-study-clean/sound/soc/ti/davinci-evm.c

File Facts

System
Linux kernel
Corpus path
sound/soc/ti/davinci-evm.c
Extension
.c
Size
7463 bytes
Lines
286
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 snd_soc_card_drvdata_davinci {
	struct clk *mclk;
	unsigned sysclk;
};

static int evm_startup(struct snd_pcm_substream *substream)
{
	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
	struct snd_soc_card *soc_card = rtd->card;
	struct snd_soc_card_drvdata_davinci *drvdata =
		snd_soc_card_get_drvdata(soc_card);

	if (drvdata->mclk)
		return clk_prepare_enable(drvdata->mclk);

	return 0;
}

static void evm_shutdown(struct snd_pcm_substream *substream)
{
	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
	struct snd_soc_card *soc_card = rtd->card;
	struct snd_soc_card_drvdata_davinci *drvdata =
		snd_soc_card_get_drvdata(soc_card);

	clk_disable_unprepare(drvdata->mclk);
}

static int evm_hw_params(struct snd_pcm_substream *substream,
			 struct snd_pcm_hw_params *params)
{
	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
	struct snd_soc_dai *codec_dai = snd_soc_rtd_to_codec(rtd, 0);
	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
	struct snd_soc_card *soc_card = rtd->card;
	int ret = 0;
	unsigned sysclk = ((struct snd_soc_card_drvdata_davinci *)
			   snd_soc_card_get_drvdata(soc_card))->sysclk;

	/* set the codec system clock */
	ret = snd_soc_dai_set_sysclk(codec_dai, 0, sysclk, SND_SOC_CLOCK_OUT);
	if (ret < 0)
		return ret;

	/* set the CPU system clock */
	ret = snd_soc_dai_set_sysclk(cpu_dai, 0, sysclk, SND_SOC_CLOCK_OUT);
	if (ret < 0 && ret != -ENOTSUPP)
		return ret;

	return 0;
}

static const struct snd_soc_ops evm_ops = {
	.startup = evm_startup,
	.shutdown = evm_shutdown,
	.hw_params = evm_hw_params,
};

/* davinci-evm machine dapm widgets */
static const struct snd_soc_dapm_widget aic3x_dapm_widgets[] = {
	SND_SOC_DAPM_HP("Headphone Jack", NULL),
	SND_SOC_DAPM_LINE("Line Out", NULL),
	SND_SOC_DAPM_MIC("Mic Jack", NULL),
	SND_SOC_DAPM_LINE("Line In", NULL),
};

/* davinci-evm machine audio_mapnections to the codec pins */
static const struct snd_soc_dapm_route audio_map[] = {
	/* Headphone connected to HPLOUT, HPROUT */
	{"Headphone Jack", NULL, "HPLOUT"},
	{"Headphone Jack", NULL, "HPROUT"},

	/* Line Out connected to LLOUT, RLOUT */
	{"Line Out", NULL, "LLOUT"},
	{"Line Out", NULL, "RLOUT"},

	/* Mic connected to (MIC3L | MIC3R) */
	{"MIC3L", NULL, "Mic Bias"},
	{"MIC3R", NULL, "Mic Bias"},
	{"Mic Bias", NULL, "Mic Jack"},

	/* Line In connected to (LINE1L | LINE2L), (LINE1R | LINE2R) */
	{"LINE1L", NULL, "Line In"},
	{"LINE2L", NULL, "Line In"},
	{"LINE1R", NULL, "Line In"},
	{"LINE2R", NULL, "Line In"},
};

/* Logic for a aic3x as connected on a davinci-evm */
static int evm_aic3x_init(struct snd_soc_pcm_runtime *rtd)

Annotation

Implementation Notes