kernel/sound/soc/codecs/spdif_receiver.c

   1 /*
   2  * ALSA SoC SPDIF DIR (Digital Interface Reciever) driver
   3  *
   4  * Based on ALSA SoC SPDIF DIT driver
   5  *
   6  *  This driver is used by controllers which can operate in DIR (SPDI/F) where
   7  *  no codec is needed.  This file provides stub codec that can be used
   8  *  in these configurations. SPEAr SPDIF IN Audio controller uses this driver.
   9  *
  10  * Author:      Vipin Kumar,  <vipin.kumar@st.com>
  11  * Copyright:   (C) 2012  ST Microelectronics
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License version 2 as
  15  * published by the Free Software Foundation.
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/moduleparam.h>
  20 #include <linux/slab.h>
  21 #include <sound/soc.h>
  22 #include <sound/pcm.h>
  23 #include <sound/initval.h>
  24 #include <linux/of.h>
  25
  26 static const struct snd_soc_dapm_widget dir_widgets[] = {
  27         SND_SOC_DAPM_INPUT("spdif-in"),
  28 };
  29
  30 static const struct snd_soc_dapm_route dir_routes[] = {
  31         { "Capture", NULL, "spdif-in" },
  32 };
  33
  34 #define STUB_RATES      SNDRV_PCM_RATE_8000_192000
  35 #define STUB_FORMATS    (SNDRV_PCM_FMTBIT_S16_LE | \
  36                         SNDRV_PCM_FMTBIT_S20_3LE | \
  37                         SNDRV_PCM_FMTBIT_S24_LE | \
  38                         SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE)
  39
  40 static struct snd_soc_codec_driver soc_codec_spdif_dir = {
  41         .dapm_widgets = dir_widgets,
  42         .num_dapm_widgets = ARRAY_SIZE(dir_widgets),
  43         .dapm_routes = dir_routes,
  44         .num_dapm_routes = ARRAY_SIZE(dir_routes),
  45 };
  46
  47 static struct snd_soc_dai_driver dir_stub_dai = {
  48         .name           = "dir-hifi",
  49         .capture        = {
  50                 .stream_name    = "Capture",
  51                 .channels_min   = 1,
  52                 .channels_max   = 384,
  53                 .rates          = STUB_RATES,
  54                 .formats        = STUB_FORMATS,
  55         },
  56 };
  57
  58 static int spdif_dir_probe(struct platform_device *pdev)
  59 {
  60         return snd_soc_register_codec(&pdev->dev, &soc_codec_spdif_dir,
  61                         &dir_stub_dai, 1);
  62 }
  63
  64 static int spdif_dir_remove(struct platform_device *pdev)
  65 {
  66         snd_soc_unregister_codec(&pdev->dev);
  67         return 0;
  68 }
  69
  70 #ifdef CONFIG_OF
  71 static const struct of_device_id spdif_dir_dt_ids[] = {
  72         { .compatible = "linux,spdif-dir", },
  73         { }
  74 };
  75 MODULE_DEVICE_TABLE(of, spdif_dir_dt_ids);
  76 #endif
  77
  78 static struct platform_driver spdif_dir_driver = {
  79         .probe          = spdif_dir_probe,
  80         .remove         = spdif_dir_remove,
  81         .driver         = {
  82                 .name   = "spdif-dir",
  83                 .of_match_table = of_match_ptr(spdif_dir_dt_ids),
  84         },
  85 };
  86
  87 module_platform_driver(spdif_dir_driver);
  88
  89 MODULE_DESCRIPTION("ASoC SPDIF DIR driver");
  90 MODULE_AUTHOR("Vipin Kumar <vipin.kumar@st.com>");
  91 MODULE_LICENSE("GPL");