ASoC: fsl_sai: Enable 'FIFO continue on error' FCONT bit

FCONT=1 means On FIFO error, the SAI will continue from the
same word that caused the FIFO error to set after the FIFO
warning flag has been cleared.

Set FCONT bit in control register to avoid the channel swap
issue after SAI xrun.

Signed-off-by: Shengjiu Wang <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>

Author: TE-N-ShengjiuWang

sound/soc/fsl/fsl_sai.c

@@ -613,6 +613,9 @@ static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
 
 	val_cr4 |= FSL_SAI_CR4_FRSZ(slots);
 
+	/* Set to avoid channel swap */
+	val_cr4 |= FSL_SAI_CR4_FCONT;
+
 	/* Set to output mode to avoid tri-stated data pins */
 	if (tx)
 		val_cr4 |= FSL_SAI_CR4_CHMOD;
@@ -699,7 +702,7 @@ static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
 
 	regmap_update_bits(sai->regmap, FSL_SAI_xCR4(tx, ofs),
 			   FSL_SAI_CR4_SYWD_MASK | FSL_SAI_CR4_FRSZ_MASK |
-			   FSL_SAI_CR4_CHMOD_MASK,
+			   FSL_SAI_CR4_CHMOD_MASK | FSL_SAI_CR4_FCONT_MASK,
 			   val_cr4);
 	regmap_update_bits(sai->regmap, FSL_SAI_xCR5(tx, ofs),
 			   FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |

sound/soc/fsl/fsl_sai.h

@@ -137,6 +137,7 @@
 
 /* SAI Transmit and Receive Configuration 4 Register */
 
+#define FSL_SAI_CR4_FCONT_MASK	BIT(28)
 #define FSL_SAI_CR4_FCONT	BIT(28)
 #define FSL_SAI_CR4_FCOMB_SHIFT BIT(26)
 #define FSL_SAI_CR4_FCOMB_SOFT  BIT(27)