ASoC: fsl_sai: Set SYNC bit of TCR2 to Asynchronous Mode

commit 855675f6e6a65688a7f4cf45b9b5a98cf6c6f5c3 upstream.

There is one design rule according to SAI's reference manual:
If the transmitter bit clock and frame sync are to be used by both transmitter
and receiver, the transmitter must be configured for asynchronous operation
and the receiver for synchronous operation.

And SYNC of TCR2 is a 2-width control bit:
00 Asynchronous mode.
01 Synchronous with receiver.
10 Synchronous with another SAI transmitter.
11 Synchronous with another SAI receiver.

So the driver should have set SYNC bit of TCR2 to 0x0, and meanwhile set SYNC
bit of RCR2 to 0x1 (Synchronous with transmitter).

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c
index c5a0e8af8226147bd8b35a3f523756cec69490c8..60465646fed8f82635f19896c1b07ea41f56d861 100644 (file)
--- a/sound/soc/fsl/fsl_sai.c
+++ b/sound/soc/fsl/fsl_sai.c
@@ -333,8 +333,7 @@ static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd,
         * The transmitter bit clock and frame sync are to be
         * used by both the transmitter and receiver.
         */
-       regmap_update_bits(sai->regmap, FSL_SAI_TCR2, FSL_SAI_CR2_SYNC,
-                          ~FSL_SAI_CR2_SYNC);
+       regmap_update_bits(sai->regmap, FSL_SAI_TCR2, FSL_SAI_CR2_SYNC, 0);
        regmap_update_bits(sai->regmap, FSL_SAI_RCR2, FSL_SAI_CR2_SYNC,
                           FSL_SAI_CR2_SYNC);