sound/soc/samsung/smdk_wm8994pcm.c

Source file repositories/reference/linux-study-clean/sound/soc/samsung/smdk_wm8994pcm.c

File Facts

System
Linux kernel
Corpus path
sound/soc/samsung/smdk_wm8994pcm.c
Extension
.c
Size
3469 bytes
Lines
139
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

// SPDX-License-Identifier: GPL-2.0+
//
// Copyright (c) 2011 Samsung Electronics Co., Ltd
//		http://www.samsung.com

#include <linux/module.h>
#include <sound/soc.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>

#include "../codecs/wm8994.h"
#include "pcm.h"

/*
 * Board Settings:
 *  o '1' means 'ON'
 *  o '0' means 'OFF'
 *  o 'X' means 'Don't care'
 *
 * SMDKC210, SMDKV310: CFG3- 1001, CFG5-1000, CFG7-111111
 */

/*
 * Configure audio route as :-
 * $ amixer sset 'DAC1' on,on
 * $ amixer sset 'Right Headphone Mux' 'DAC'
 * $ amixer sset 'Left Headphone Mux' 'DAC'
 * $ amixer sset 'DAC1R Mixer AIF1.1' on
 * $ amixer sset 'DAC1L Mixer AIF1.1' on
 * $ amixer sset 'IN2L' on
 * $ amixer sset 'IN2L PGA IN2LN' on
 * $ amixer sset 'MIXINL IN2L' on
 * $ amixer sset 'AIF1ADC1L Mixer ADC/DMIC' on
 * $ amixer sset 'IN2R' on
 * $ amixer sset 'IN2R PGA IN2RN' on
 * $ amixer sset 'MIXINR IN2R' on
 * $ amixer sset 'AIF1ADC1R Mixer ADC/DMIC' on
 */

/* SMDK has a 16.9344MHZ crystal attached to WM8994 */
#define SMDK_WM8994_FREQ 16934400

static int smdk_wm8994_pcm_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);
	unsigned long mclk_freq;
	int rfs, ret;

	switch(params_rate(params)) {
	case 8000:
		rfs = 512;
		break;
	default:
		dev_err(cpu_dai->dev, "%s:%d Sampling Rate %u not supported!\n",
		__func__, __LINE__, params_rate(params));
		return -EINVAL;
	}

	mclk_freq = params_rate(params) * rfs;

	ret = snd_soc_dai_set_sysclk(codec_dai, WM8994_SYSCLK_FLL1,
					mclk_freq, SND_SOC_CLOCK_IN);
	if (ret < 0)
		return ret;

	ret = snd_soc_dai_set_pll(codec_dai, WM8994_FLL1, WM8994_FLL_SRC_MCLK1,
					SMDK_WM8994_FREQ, mclk_freq);
	if (ret < 0)
		return ret;

	/* Set PCM source clock on CPU */
	ret = snd_soc_dai_set_sysclk(cpu_dai, S3C_PCM_CLKSRC_MUX,
					mclk_freq, SND_SOC_CLOCK_IN);
	if (ret < 0)
		return ret;

	/* Set SCLK_DIV for making bclk */
	ret = snd_soc_dai_set_clkdiv(cpu_dai, S3C_PCM_SCLK_PER_FS, rfs);
	if (ret < 0)
		return ret;

	return 0;
}

static const struct snd_soc_ops smdk_wm8994_pcm_ops = {
	.hw_params = smdk_wm8994_pcm_hw_params,
};

Annotation

Implementation Notes