sound/soc/samsung/littlemill.c

Source file repositories/reference/linux-study-clean/sound/soc/samsung/littlemill.c

File Facts

System
Linux kernel
Corpus path
sound/soc/samsung/littlemill.c
Extension
.c
Size
8842 bytes
Lines
361
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

if (snd_soc_dapm_get_bias_level(dapm) == SND_SOC_BIAS_STANDBY) {
			ret = snd_soc_dai_set_pll(aif1_dai, WM8994_FLL1,
						  WM8994_FLL_SRC_MCLK2, 32768,
						  sample_rate * 512);
			if (ret < 0) {
				pr_err("Failed to start FLL: %d\n", ret);
				return ret;
			}

			ret = snd_soc_dai_set_sysclk(aif1_dai,
						     WM8994_SYSCLK_FLL1,
						     sample_rate * 512,
						     SND_SOC_CLOCK_IN);
			if (ret < 0) {
				pr_err("Failed to set SYSCLK: %d\n", ret);
				return ret;
			}
		}
		break;

	default:
		break;
	}

	return 0;
}

static int littlemill_set_bias_level_post(struct snd_soc_card *card,
					       struct snd_soc_dapm_context *dapm,
					       enum snd_soc_bias_level level)
{
	struct snd_soc_pcm_runtime *rtd;
	struct snd_soc_dai *aif1_dai;
	int ret;

	rtd = snd_soc_get_pcm_runtime(card, &card->dai_link[0]);
	aif1_dai = snd_soc_rtd_to_codec(rtd, 0);

	if (snd_soc_dapm_to_dev(dapm) != aif1_dai->dev)
		return 0;

	switch (level) {
	case SND_SOC_BIAS_STANDBY:
		ret = snd_soc_dai_set_sysclk(aif1_dai, WM8994_SYSCLK_MCLK2,
					     32768, SND_SOC_CLOCK_IN);
		if (ret < 0) {
			pr_err("Failed to switch away from FLL1: %d\n", ret);
			return ret;
		}

		ret = snd_soc_dai_set_pll(aif1_dai, WM8994_FLL1,
					  0, 0, 0);
		if (ret < 0) {
			pr_err("Failed to stop FLL1: %d\n", ret);
			return ret;
		}
		break;

	default:
		break;
	}

	return 0;
}

static int littlemill_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);
	int ret;

	sample_rate = params_rate(params);

	ret = snd_soc_dai_set_pll(codec_dai, WM8994_FLL1,
				  WM8994_FLL_SRC_MCLK2, 32768,
				  sample_rate * 512);
	if (ret < 0) {
		pr_err("Failed to start FLL: %d\n", ret);
		return ret;
	}

	ret = snd_soc_dai_set_sysclk(codec_dai,
				     WM8994_SYSCLK_FLL1,
				     sample_rate * 512,
				     SND_SOC_CLOCK_IN);
	if (ret < 0) {
		pr_err("Failed to set SYSCLK: %d\n", ret);
		return ret;
	}

Annotation

Implementation Notes