1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * ALSA SoC SPDIF DIR (Digital Interface Reciever) driver
4 *
5 * Based on ALSA SoC SPDIF DIT driver
6 *
7 * This driver is used by controllers which can operate in DIR (SPDI/F) where
8 * no codec is needed. This file provides stub codec that can be used
9 * in these configurations. SPEAr SPDIF IN Audio controller uses this driver.
10 *
11 * Author: Vipin Kumar, <vipin.kumar@st.com>
12 * Copyright: (C) 2012 ST Microelectronics
13 */
14
15#include <linux/module.h>
16#include <linux/moduleparam.h>
17#include <linux/slab.h>
18#include <sound/soc.h>
19#include <sound/pcm.h>
20#include <sound/initval.h>
21#include <linux/of.h>
22
23static const struct snd_soc_dapm_widget dir_widgets[] = {
24 SND_SOC_DAPM_INPUT("spdif-in"),
25};
26
27static const struct snd_soc_dapm_route dir_routes[] = {
28 { "Capture", NULL, "spdif-in" },
29};
30
31#define STUB_RATES SNDRV_PCM_RATE_8000_192000
32#define STUB_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | \
33 SNDRV_PCM_FMTBIT_S20_3LE | \
34 SNDRV_PCM_FMTBIT_S24_LE | \
35 SNDRV_PCM_FMTBIT_S32_LE | \
36 SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE)
37
38static struct snd_soc_component_driver soc_codec_spdif_dir = {
39 .dapm_widgets = dir_widgets,
40 .num_dapm_widgets = ARRAY_SIZE(dir_widgets),
41 .dapm_routes = dir_routes,
42 .num_dapm_routes = ARRAY_SIZE(dir_routes),
43 .idle_bias_on = 1,
44 .use_pmdown_time = 1,
45 .endianness = 1,
46};
47
48static struct snd_soc_dai_driver dir_stub_dai = {
49 .name = "dir-hifi",
50 .capture = {
51 .stream_name = "Capture",
52 .channels_min = 1,
53 .channels_max = 384,
54 .rates = STUB_RATES,
55 .formats = STUB_FORMATS,
56 },
57};
58
59static int spdif_dir_probe(struct platform_device *pdev)
60{
61 return devm_snd_soc_register_component(dev: &pdev->dev,
62 component_driver: &soc_codec_spdif_dir,
63 dai_drv: &dir_stub_dai, num_dai: 1);
64}
65
66#ifdef CONFIG_OF
67static const struct of_device_id spdif_dir_dt_ids[] = {
68 { .compatible = "linux,spdif-dir", },
69 { }
70};
71MODULE_DEVICE_TABLE(of, spdif_dir_dt_ids);
72#endif
73
74static struct platform_driver spdif_dir_driver = {
75 .probe = spdif_dir_probe,
76 .driver = {
77 .name = "spdif-dir",
78 .of_match_table = of_match_ptr(spdif_dir_dt_ids),
79 },
80};
81
82module_platform_driver(spdif_dir_driver);
83
84MODULE_DESCRIPTION("ASoC SPDIF DIR driver");
85MODULE_AUTHOR("Vipin Kumar <vipin.kumar@st.com>");
86MODULE_LICENSE("GPL");
87

source code of linux/sound/soc/codecs/spdif_receiver.c