[PATCH] ASoC: fsl_asrc: Set ASR76K and ASR56K based on processing clock

Shengjiu Wang shengjiu.wang at nxp.com
Tue May 12 20:22:59 AEST 2020


The processing clock is different for platforms, so it is better
to set ASR76K and ASR56K based on processing clock, rather than
hard coding the value for them.

Signed-off-by: Shengjiu Wang <shengjiu.wang at nxp.com>
Signed-off-by: Mihai Serban <mihai.serban at nxp.com>
---
 sound/soc/fsl/fsl_asrc.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/sound/soc/fsl/fsl_asrc.c b/sound/soc/fsl/fsl_asrc.c
index 067a54ab554f..ca926915068f 100644
--- a/sound/soc/fsl/fsl_asrc.c
+++ b/sound/soc/fsl/fsl_asrc.c
@@ -858,6 +858,8 @@ static const struct regmap_config fsl_asrc_regmap_config = {
  */
 static int fsl_asrc_init(struct fsl_asrc *asrc)
 {
+	unsigned long ipg_rate;
+
 	/* Halt ASRC internal FP when input FIFO needs data for pair A, B, C */
 	regmap_write(asrc->regmap, REG_ASRCTR, ASRCTR_ASRCEN);
 
@@ -875,11 +877,14 @@ static int fsl_asrc_init(struct fsl_asrc *asrc)
 	regmap_update_bits(asrc->regmap, REG_ASRTFR1,
 			   ASRTFR1_TF_BASE_MASK, ASRTFR1_TF_BASE(0xfc));
 
-	/* Set the processing clock for 76KHz to 133M */
-	regmap_write(asrc->regmap, REG_ASR76K, 0x06D6);
-
-	/* Set the processing clock for 56KHz to 133M */
-	return regmap_write(asrc->regmap, REG_ASR56K, 0x0947);
+	/*
+	 * Set the period of the 76KHz and 56KHz sampling clocks based on
+	 * the ASRC processing clock.
+	 * On iMX6, ipg_clk = 133MHz, REG_ASR76K = 0x06D6, REG_ASR56K = 0x0947
+	 */
+	ipg_rate = clk_get_rate(asrc->ipg_clk);
+	regmap_write(asrc->regmap, REG_ASR76K, ipg_rate / 76000);
+	return regmap_write(asrc->regmap, REG_ASR56K, ipg_rate / 56000);
 }
 
 /**
-- 
2.21.0



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