[PATCH v2 2/2] ASoC: fsl_asrc: always use internal ratio

From: Arnaud Ferraris
Date: Thu Jul 16 2020 - 11:15:22 EST


Even though the current driver calculates the dividers to be used
depending on the clocks and sample rates, enabling the internal ratio
can lead to noticeable improvements in the audio quality, based on my
testing.

As stated in the documentation, "When USRx=1 and IDRx=0, ASRC internal
measured ratio will be used", so setting this bit even when not in
"Ideal Ratio" mode still makes sense.

Signed-off-by: Arnaud Ferraris <arnaud.ferraris@xxxxxxxxxxxxx>
---
sound/soc/fsl/fsl_asrc.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/sound/soc/fsl/fsl_asrc.c b/sound/soc/fsl/fsl_asrc.c
index 6d43cab6c885..0b79a02d0d76 100644
--- a/sound/soc/fsl/fsl_asrc.c
+++ b/sound/soc/fsl/fsl_asrc.c
@@ -465,7 +465,7 @@ static int fsl_asrc_config_pair(struct fsl_asrc_pair *pair, bool use_ideal_rate)
regmap_update_bits(asrc->regmap, REG_ASRCTR,
ASRCTR_ATSi_MASK(index), ASRCTR_ATS(index));
regmap_update_bits(asrc->regmap, REG_ASRCTR,
- ASRCTR_USRi_MASK(index), 0);
+ ASRCTR_USRi_MASK(index), ASRCTR_USR(index));

/* Set the input and output clock sources */
regmap_update_bits(asrc->regmap, REG_ASRCSR,
@@ -507,8 +507,7 @@ static int fsl_asrc_config_pair(struct fsl_asrc_pair *pair, bool use_ideal_rate)

/* Enable Ideal Ratio mode */
regmap_update_bits(asrc->regmap, REG_ASRCTR,
- ASRCTR_IDRi_MASK(index) | ASRCTR_USRi_MASK(index),
- ASRCTR_IDR(index) | ASRCTR_USR(index));
+ ASRCTR_IDRi_MASK(index), ASRCTR_IDR(index);

fsl_asrc_sel_proc(inrate, outrate, &pre_proc, &post_proc);

--
2.27.0