sound/soc/meson/gx-card.c

Source file repositories/reference/linux-study-clean/sound/soc/meson/gx-card.c

File Facts

System
Linux kernel
Corpus path
sound/soc/meson/gx-card.c
Extension
.c
Size
3647 bytes
Lines
143
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 gx_dai_link_i2s_data {
	unsigned int mclk_fs;
};

/*
 * Base params for the codec to codec links
 * Those will be over-written by the CPU side of the link
 */
static const struct snd_soc_pcm_stream codec_params = {
	.formats = SNDRV_PCM_FMTBIT_S24_LE,
	.rate_min = 5525,
	.rate_max = 192000,
	.channels_min = 1,
	.channels_max = 8,
};

static int gx_card_i2s_be_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 meson_card *priv = snd_soc_card_get_drvdata(rtd->card);
	struct gx_dai_link_i2s_data *be =
		(struct gx_dai_link_i2s_data *)priv->link_data[rtd->id];

	return meson_card_i2s_set_sysclk(substream, params, be->mclk_fs);
}

static const struct snd_soc_ops gx_card_i2s_be_ops = {
	.hw_params = gx_card_i2s_be_hw_params,
};

static int gx_card_parse_i2s(struct snd_soc_card *card,
			     struct device_node *node,
			     int *index)
{
	struct meson_card *priv = snd_soc_card_get_drvdata(card);
	struct snd_soc_dai_link *link = &card->dai_link[*index];
	struct gx_dai_link_i2s_data *be;

	/* Allocate i2s link parameters */
	be = devm_kzalloc(card->dev, sizeof(*be), GFP_KERNEL);
	if (!be)
		return -ENOMEM;
	priv->link_data[*index] = be;

	/* Setup i2s link */
	link->ops = &gx_card_i2s_be_ops;
	link->dai_fmt = meson_card_parse_daifmt(node, link->cpus->of_node);

	of_property_read_u32(node, "mclk-fs", &be->mclk_fs);

	return 0;
}

static int gx_card_cpu_identify(struct snd_soc_dai_link_component *c,
				char *match)
{
	if (of_device_is_compatible(c->of_node, DT_PREFIX "aiu")) {
		if (strstr(c->dai_name, match))
			return 1;
	}

	/* dai not matched */
	return 0;
}

static int gx_card_add_link(struct snd_soc_card *card, struct device_node *np,
			    int *index)
{
	struct snd_soc_dai_link *dai_link = &card->dai_link[*index];
	struct snd_soc_dai_link_component *cpu;
	int ret;

	cpu = devm_kzalloc(card->dev, sizeof(*cpu), GFP_KERNEL);
	if (!cpu)
		return -ENOMEM;

	dai_link->cpus = cpu;
	dai_link->num_cpus = 1;

	ret = meson_card_parse_dai(card, np, dai_link->cpus);
	if (ret)
		return ret;

	if (gx_card_cpu_identify(dai_link->cpus, "FIFO"))
		return  meson_card_set_fe_link(card, dai_link, np, true);

	ret = meson_card_set_be_link(card, dai_link, np);
	if (ret)
		return ret;

Annotation

Implementation Notes