target/linux/brcm2708/patches-3.18/0084-Add-a-parameter-to-turn-off-SPDIF-output-if-no-audio.patch

   1 From a09a8ebce7251e2a42668bd5ae57c12ed24fdca8 Mon Sep 17 00:00:00 2001
   2 From: Daniel Matuschek <daniel@hifiberry.com>
   3 Date: Sat, 31 Jan 2015 16:07:56 +0100
   4 Subject: [PATCH 084/114] Add a parameter to turn off SPDIF output if no audio
   5  is playing
   6
   7 This patch adds the paramater auto_shutdown_output to the kernel module.
   8 Default behaviour of the module is the same, but when auto_shutdown_output
   9 is set to 1, the SPDIF oputput will shutdown if no stream is playing.
  10 ---
  11  sound/soc/bcm/hifiberry_digi.c | 29 ++++++++++++++++++++++++++++-
  12  1 file changed, 28 insertions(+), 1 deletion(-)
  13
  14 --- a/sound/soc/bcm/hifiberry_digi.c
  15 +++ b/sound/soc/bcm/hifiberry_digi.c
  16 @@ -26,6 +26,11 @@
  17
  18  #include "../codecs/wm8804.h"
  19
  20 +static short int auto_shutdown_output = 0;
  21 +module_param(auto_shutdown_output, short, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
  22 +MODULE_PARM_DESC(auto_shutdown_output, "Shutdown SP/DIF output if playback is stopped");
  23 +
  24 +
  25  static int samplerate=44100;
  26
  27  static int snd_rpi_hifiberry_digi_init(struct snd_soc_pcm_runtime *rtd)
  28 @@ -38,6 +43,25 @@ static int snd_rpi_hifiberry_digi_init(s
  29         return 0;
  30  }
  31
  32 +static int snd_rpi_hifiberry_digi_startup(struct snd_pcm_substream *substream) {
  33 +       /* turn on digital output */
  34 +       struct snd_soc_pcm_runtime *rtd = substream->private_data;
  35 +       struct snd_soc_codec *codec = rtd->codec;
  36 +       snd_soc_update_bits(codec, WM8804_PWRDN, 0x3c, 0x00);
  37 +       return 0;
  38 +}
  39 +
  40 +static void snd_rpi_hifiberry_digi_shutdown(struct snd_pcm_substream *substream) {
  41 +       /* turn off output */
  42 +       if (auto_shutdown_output) {
  43 +               /* turn off output */
  44 +               struct snd_soc_pcm_runtime *rtd = substream->private_data;
  45 +               struct snd_soc_codec *codec = rtd->codec;
  46 +               snd_soc_update_bits(codec, WM8804_PWRDN, 0x3c, 0x3c);
  47 +       }
  48 +}
  49 +
  50 +
  51  static int snd_rpi_hifiberry_digi_hw_params(struct snd_pcm_substream *substream,
  52                                        struct snd_pcm_hw_params *params)
  53  {
  54 @@ -70,7 +94,8 @@ static int snd_rpi_hifiberry_digi_hw_par
  55                         break;
  56                 default:
  57                         dev_err(substream->pcm->dev,
  58 -                       "Failed to set WM8804 SYSCLK, unsupported samplerate\n");
  59 +                       "Failed to set WM8804 SYSCLK, unsupported samplerate %d\n",
  60 +                       samplerate);
  61         }
  62
  63         snd_soc_dai_set_clkdiv(codec_dai, WM8804_MCLK_DIV, mclk_div);
  64 @@ -96,6 +121,8 @@ static int snd_rpi_hifiberry_digi_hw_par
  65  /* machine stream operations */
  66  static struct snd_soc_ops snd_rpi_hifiberry_digi_ops = {
  67         .hw_params = snd_rpi_hifiberry_digi_hw_params,
  68 +        .startup = snd_rpi_hifiberry_digi_startup,
  69 +        .shutdown = snd_rpi_hifiberry_digi_shutdown,
  70  };
  71
  72  static struct snd_soc_dai_link snd_rpi_hifiberry_digi_dai[] = {