target/linux/brcm2708/patches-4.4/0571-Revert-bcm2835-i2s-Changes-for-allowing-asymmetric-s.patch

   1 From ba1f22a0d2179a0201e764c341d9dbf8f1c27ffe Mon Sep 17 00:00:00 2001
   2 From: Phil Elwell <phil@raspberrypi.org>
   3 Date: Mon, 16 Jan 2017 20:58:18 +0000
   4 Subject: [PATCH] Revert "bcm2835-i2s: Changes for allowing asymmetric sample
   5  formats. (#1783)"
   6
   7 This reverts commit 4897c5c2f7adb4f77d638121e9959174dff87b9c.
   8
   9 Signed-off-by: Phil Elwell <phil@raspberrypi.org>
  10
  11 See: https://github.com/raspberrypi/linux/issues/1799
  12 ---
  13  sound/soc/bcm/bcm2835-i2s.c | 54 ++++++++++++++-------------------------------
  14  1 file changed, 16 insertions(+), 38 deletions(-)
  15
  16 --- a/sound/soc/bcm/bcm2835-i2s.c
  17 +++ b/sound/soc/bcm/bcm2835-i2s.c
  18 @@ -310,7 +310,6 @@ static int bcm2835_i2s_hw_params(struct
  19         unsigned int sampling_rate = params_rate(params);
  20         unsigned int data_length, data_delay, bclk_ratio;
  21         unsigned int ch1pos, ch2pos, mode, format;
  22 -       unsigned int previous_ftxp, previous_frxp;
  23         unsigned int mash = BCM2835_CLK_MASH_1;
  24         unsigned int divi, divf, target_frequency;
  25         int clk_src = -1;
  26 @@ -321,7 +320,6 @@ static int bcm2835_i2s_hw_params(struct
  27         bool frame_master =     (master == SND_SOC_DAIFMT_CBS_CFS
  28                                         || master == SND_SOC_DAIFMT_CBM_CFS);
  29         uint32_t csreg;
  30 -       bool packed;
  31
  32         /*
  33          * If a stream is already enabled,
  34 @@ -467,46 +465,26 @@ static int bcm2835_i2s_hw_params(struct
  35                 return -EINVAL;
  36         }
  37
  38 -       /* Set the format for the matching stream direction. */
  39 -       switch (substream->stream) {
  40 -       case SNDRV_PCM_STREAM_PLAYBACK:
  41 -               regmap_write(dev->i2s_regmap, BCM2835_I2S_TXC_A_REG, format);
  42 -               break;
  43 -       case SNDRV_PCM_STREAM_CAPTURE:
  44 -               regmap_write(dev->i2s_regmap, BCM2835_I2S_RXC_A_REG, format);
  45 -               break;
  46 -       default:
  47 -               return -EINVAL;
  48 -       }
  49 +       /*
  50 +        * Set format for both streams.
  51 +        * We cannot set another frame length
  52 +        * (and therefore word length) anyway,
  53 +        * so the format will be the same.
  54 +        */
  55 +       regmap_write(dev->i2s_regmap, BCM2835_I2S_RXC_A_REG, format);
  56 +       regmap_write(dev->i2s_regmap, BCM2835_I2S_TXC_A_REG, format);
  57
  58         /* Setup the I2S mode */
  59 -       /* Keep existing FTXP and FRXP values. */
  60 -       regmap_read(dev->i2s_regmap, BCM2835_I2S_MODE_A_REG, &mode);
  61 -
  62 -       previous_ftxp = mode & BCM2835_I2S_FTXP;
  63 -       previous_frxp = mode & BCM2835_I2S_FRXP;
  64 -
  65         mode = 0;
  66
  67 -       /*
  68 -        * Retain the frame packed mode (2 channels per 32 bit word)
  69 -        * of the other direction stream intact. The formats of each
  70 -        * direction can be different as long as the frame length is
  71 -        * shared for both.
  72 -        */
  73 -       packed = data_length <= 16;
  74 -
  75 -       switch (substream->stream) {
  76 -       case SNDRV_PCM_STREAM_PLAYBACK:
  77 -               mode |= previous_frxp;
  78 -               mode |= packed ? BCM2835_I2S_FTXP : 0;
  79 -               break;
  80 -       case SNDRV_PCM_STREAM_CAPTURE:
  81 -               mode |= previous_ftxp;
  82 -               mode |= packed ? BCM2835_I2S_FRXP : 0;
  83 -               break;
  84 -       default:
  85 -               return -EINVAL;
  86 +       if (data_length <= 16) {
  87 +               /*
  88 +                * Use frame packed mode (2 channels per 32 bit word)
  89 +                * We cannot set another frame length in the second stream
  90 +                * (and therefore word length) anyway,
  91 +                * so the format will be the same.
  92 +                */
  93 +               mode |= BCM2835_I2S_FTXP | BCM2835_I2S_FRXP;
  94         }
  95
  96         mode |= BCM2835_I2S_FLEN(bclk_ratio - 1);