From: Chancel Liu <chancel.liu@xxxxxxx> [ Upstream commit 3ca507bf99611c82dafced73e921c1b10ee12869 ] DSPCLK_DIV field in WM8962_CLOCKING1 register is used to generate correct frequency of LRCLK and BCLK. Sometimes the read-only value can't be updated timely after enabling SYSCLK. This results in wrong calculation values. Delay is introduced here to wait for newest value from register. The time of the delay should be at least 500~1000us according to test. Signed-off-by: Chancel Liu <chancel.liu@xxxxxxx> Acked-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20221109121354.123958-1-chancel.liu@xxxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- sound/soc/codecs/wm8962.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/sound/soc/codecs/wm8962.c b/sound/soc/codecs/wm8962.c index 6df06fba4377..ee1cad5af535 100644 --- a/sound/soc/codecs/wm8962.c +++ b/sound/soc/codecs/wm8962.c @@ -2503,6 +2503,14 @@ static void wm8962_configure_bclk(struct snd_soc_component *component) snd_soc_component_update_bits(component, WM8962_CLOCKING2, WM8962_SYSCLK_ENA_MASK, WM8962_SYSCLK_ENA); + /* DSPCLK_DIV field in WM8962_CLOCKING1 register is used to generate + * correct frequency of LRCLK and BCLK. Sometimes the read-only value + * can't be updated timely after enabling SYSCLK. This results in wrong + * calculation values. Delay is introduced here to wait for newest + * value from register. The time of the delay should be at least + * 500~1000us according to test. + */ + usleep_range(500, 1000); dspclk = snd_soc_component_read(component, WM8962_CLOCKING1); if (snd_soc_component_get_bias_level(component) != SND_SOC_BIAS_ON) -- 2.35.1
