On Thu, Jul 16, 2020 at 05:13:54PM +0200, Arnaud Ferraris wrote:
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@collabora.com
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 */
The code is against the comments now -- need to update this line.
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);
The driver falls back to ideal ratio mode if there is no matched clock source. Your change seems to apply internal ratio mode any way? Probably would break the fallback routine.