sound/soc/atmel/atmel_wm8904.c
Source file repositories/reference/linux-study-clean/sound/soc/atmel/atmel_wm8904.c
File Facts
- System
- Linux kernel
- Corpus path
sound/soc/atmel/atmel_wm8904.c- Extension
.c- Size
- 5097 bytes
- Lines
- 199
- 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.
- 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.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/clk.hlinux/module.hlinux/of.hsound/soc.h../codecs/wm8904.hatmel_ssc_dai.h
Detected Declarations
function atmel_asoc_wm8904_hw_paramsfunction atmel_asoc_wm8904_dt_initfunction atmel_asoc_wm8904_probefunction atmel_asoc_wm8904_remove
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* atmel_wm8904 - Atmel ASoC driver for boards with WM8904 codec.
*
* Copyright (C) 2012 Atmel
*
* Author: Bo Shen <voice.shen@atmel.com>
*/
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/of.h>
#include <sound/soc.h>
#include "../codecs/wm8904.h"
#include "atmel_ssc_dai.h"
static const struct snd_soc_dapm_widget atmel_asoc_wm8904_dapm_widgets[] = {
SND_SOC_DAPM_HP("Headphone Jack", NULL),
SND_SOC_DAPM_MIC("Mic", NULL),
SND_SOC_DAPM_LINE("Line In Jack", NULL),
};
static int atmel_asoc_wm8904_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;
ret = snd_soc_dai_set_pll(codec_dai, WM8904_FLL_MCLK, WM8904_FLL_MCLK,
32768, params_rate(params) * 256);
if (ret < 0) {
pr_err("%s - failed to set wm8904 codec PLL.", __func__);
return ret;
}
/*
* As here wm8904 use FLL output as its system clock
* so calling set_sysclk won't care freq parameter
* then we pass 0
*/
ret = snd_soc_dai_set_sysclk(codec_dai, WM8904_CLK_FLL,
0, SND_SOC_CLOCK_IN);
if (ret < 0) {
pr_err("%s -failed to set wm8904 SYSCLK\n", __func__);
return ret;
}
return 0;
}
static const struct snd_soc_ops atmel_asoc_wm8904_ops = {
.hw_params = atmel_asoc_wm8904_hw_params,
};
SND_SOC_DAILINK_DEFS(pcm,
DAILINK_COMP_ARRAY(COMP_EMPTY()),
DAILINK_COMP_ARRAY(COMP_CODEC(NULL, "wm8904-hifi")),
DAILINK_COMP_ARRAY(COMP_EMPTY()));
static struct snd_soc_dai_link atmel_asoc_wm8904_dailink = {
.name = "WM8904",
.stream_name = "WM8904 PCM",
.dai_fmt = SND_SOC_DAIFMT_I2S
| SND_SOC_DAIFMT_NB_NF
| SND_SOC_DAIFMT_CBP_CFP,
.ops = &atmel_asoc_wm8904_ops,
SND_SOC_DAILINK_REG(pcm),
};
static struct snd_soc_card atmel_asoc_wm8904_card = {
.name = "atmel_asoc_wm8904",
.owner = THIS_MODULE,
.dai_link = &atmel_asoc_wm8904_dailink,
.num_links = 1,
.dapm_widgets = atmel_asoc_wm8904_dapm_widgets,
.num_dapm_widgets = ARRAY_SIZE(atmel_asoc_wm8904_dapm_widgets),
.fully_routed = true,
};
static int atmel_asoc_wm8904_dt_init(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct device_node *codec_np, *cpu_np;
struct snd_soc_card *card = &atmel_asoc_wm8904_card;
struct snd_soc_dai_link *dailink = &atmel_asoc_wm8904_dailink;
int ret;
Annotation
- Immediate include surface: `linux/clk.h`, `linux/module.h`, `linux/of.h`, `sound/soc.h`, `../codecs/wm8904.h`, `atmel_ssc_dai.h`.
- Detected declarations: `function atmel_asoc_wm8904_hw_params`, `function atmel_asoc_wm8904_dt_init`, `function atmel_asoc_wm8904_probe`, `function atmel_asoc_wm8904_remove`.
- Atlas domain: Driver Families / sound/soc.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.