sound/soc/codecs/spdif_transmitter.c

   1 /*
   2  * ALSA SoC SPDIF DIT driver
   3  *
   4  *  This driver is used by controllers which can operate in DIT (SPDI/F) where
   5  *  no codec is needed.  This file provides stub codec that can be used
   6  *  in these configurations. TI DaVinci Audio controller uses this driver.
   7  *
   8  * Author:      Steve Chen,  <schen@mvista.com>
   9  * Copyright:   (C) 2009 MontaVista Software, Inc., <source@mvista.com>
  10  * Copyright:   (C) 2009  Texas Instruments, India
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15  */
  16
  17 #include <linux/module.h>
  18 #include <linux/moduleparam.h>
  19 #include <linux/slab.h>
  20 #include <sound/soc.h>
  21 #include <sound/pcm.h>
  22 #include <sound/initval.h>
  23 #include <linux/of.h>
  24
  25 #define DRV_NAME "spdif-dit"
  26
  27 #define STUB_RATES      SNDRV_PCM_RATE_8000_192000
  28 #define STUB_FORMATS    (SNDRV_PCM_FMTBIT_S16_LE | \
  29                         SNDRV_PCM_FMTBIT_S20_3LE | \
  30                         SNDRV_PCM_FMTBIT_S24_LE  | \
  31                         SNDRV_PCM_FMTBIT_S32_LE)
  32
  33 static const struct snd_soc_dapm_widget dit_widgets[] = {
  34         SND_SOC_DAPM_OUTPUT("spdif-out"),
  35 };
  36
  37 static const struct snd_soc_dapm_route dit_routes[] = {
  38         { "spdif-out", NULL, "Playback" },
  39 };
  40
  41 static struct snd_soc_component_driver soc_codec_spdif_dit = {
  42         .dapm_widgets           = dit_widgets,
  43         .num_dapm_widgets       = ARRAY_SIZE(dit_widgets),
  44         .dapm_routes            = dit_routes,
  45         .num_dapm_routes        = ARRAY_SIZE(dit_routes),
  46         .idle_bias_on           = 1,
  47         .use_pmdown_time        = 1,
  48         .endianness             = 1,
  49         .non_legacy_dai_naming  = 1,
  50 };
  51
  52 static struct snd_soc_dai_driver dit_stub_dai = {
  53         .name           = "dit-hifi",
  54         .playback       = {
  55                 .stream_name    = "Playback",
  56                 .channels_min   = 1,
  57                 .channels_max   = 384,
  58                 .rates          = STUB_RATES,
  59                 .formats        = STUB_FORMATS,
  60         },
  61 };
  62
  63 static int spdif_dit_probe(struct platform_device *pdev)
  64 {
  65         return devm_snd_soc_register_component(&pdev->dev,
  66                         &soc_codec_spdif_dit,
  67                         &dit_stub_dai, 1);
  68 }
  69
  70 #ifdef CONFIG_OF
  71 static const struct of_device_id spdif_dit_dt_ids[] = {
  72         { .compatible = "linux,spdif-dit", },
  73         { }
  74 };
  75 MODULE_DEVICE_TABLE(of, spdif_dit_dt_ids);
  76 #endif
  77
  78 static struct platform_driver spdif_dit_driver = {
  79         .probe          = spdif_dit_probe,
  80         .driver         = {
  81                 .name   = DRV_NAME,
  82                 .of_match_table = of_match_ptr(spdif_dit_dt_ids),
  83         },
  84 };
  85
  86 module_platform_driver(spdif_dit_driver);
  87
  88 MODULE_AUTHOR("Steve Chen <schen@mvista.com>");
  89 MODULE_DESCRIPTION("SPDIF dummy codec driver");
  90 MODULE_LICENSE("GPL");
  91 MODULE_ALIAS("platform:" DRV_NAME);