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>
This commit is contained in:
Michal Bachraty 2013-04-19 15:28:44 +02:00 committed by Mark Brown
parent 7c21a78104
commit d486fea6ba
2 changed files with 5 additions and 4 deletions

View File

@ -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;

View File

@ -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;