ASoC: davinci-mcasp: Add Support BCLK-to-LRCLK ratio for TDM modes

For TDM mode, BCLK-to-LCLK ratio is computed as (tdm_slots) x (word_length).
I2S mode is only subset of TDM mode with specific tdm_slots = 2 channels.
Also bclk_lrclk_ratio can be greater than 255, therefore u16 need to be used.

Signed-off-by: Michal Bachraty <michal.bachraty@streamunlimited.com>
Acked-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

2 files changed, 5 insertions, 4 deletions

diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c
index 59143373afc6..8b85049daab0 100644
--- a/sound/soc/davinci/davinci-mcasp.c
+++ b/sound/soc/davinci/davinci-mcasp.c
@@ -636,11 +636,12 @@ static int davinci_config_channel_size(struct davinci_audio_dev *dev,
          * callback, take it into account here. That allows us to for example
          * send 32 bits per channel to the codec, while only 16 of them carry
          * audio payload.
-         * The clock ratio is given for a full period of data (both left and
-         * right channels), so it has to be divided by 2.
+         * The clock ratio is given for a full period of data (for I2S format
+         * both left and right channels), so it has to be divided by number of
+         * tdm-slots (for I2S - divided by 2).
          */
         if (dev->bclk_lrclk_ratio)
-                word_length = dev->bclk_lrclk_ratio / 2;
+                word_length = dev->bclk_lrclk_ratio / dev->tdm_slots;
 
         /* mapping of the XSSZ bit-field as described in the datasheet */
         fmt = (word_length >> 1) - 1;
diff --git a/sound/soc/davinci/davinci-mcasp.h b/sound/soc/davinci/davinci-mcasp.h
index 0edd3b5a37fd..a9ac0c11da71 100644
--- a/sound/soc/davinci/davinci-mcasp.h
+++ b/sound/soc/davinci/davinci-mcasp.h
@@ -38,7 +38,7 @@ struct davinci_audio_dev {
         u8      num_serializer;
         u8      *serial_dir;
         u8      version;
-        u8      bclk_lrclk_ratio;
+        u16     bclk_lrclk_ratio;
 
         /* McASP FIFO related */
         u8      txnumevt;