From: Shengjiu Wang shengjiu.wang@nxp.com
[ Upstream commit 16b82e75c15a7dbd564ea3654f3feb61df9e1e6f ]
The input MCLK is 12.288MHz, the desired output sysclk is 11.2896MHz and sample rate is 44100Hz, with the configuration pllprescale=2, postscale=sysclkdiv=1, some chip may have wrong bclk and lrclk output with pll enabled in master mode, but with the configuration pllprescale=1, postscale=2, the output clock is correct.
From Datasheet, the PLL performs best when f2 is between
90MHz and 100MHz when the desired sysclk output is 11.2896MHz or 12.288MHz, so sysclkdiv = 2 (f2/8) is the best choice.
So search available sysclk_divs from 2 to 1 other than from 1 to 2.
Fixes: 84fdc00d519f ("ASoC: codec: wm9860: Refactor PLL out freq search") Signed-off-by: Shengjiu Wang shengjiu.wang@nxp.com Acked-by: Charles Keepax ckeepax@opensource.cirrus.com Link: https://lore.kernel.org/r/1616150926-22892-1-git-send-email-shengjiu.wang@nx... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- sound/soc/codecs/wm8960.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/sound/soc/codecs/wm8960.c b/sound/soc/codecs/wm8960.c index 660ec46eecf2..ceaf3bbb18e6 100644 --- a/sound/soc/codecs/wm8960.c +++ b/sound/soc/codecs/wm8960.c @@ -707,7 +707,13 @@ int wm8960_configure_pll(struct snd_soc_component *component, int freq_in, best_freq_out = -EINVAL; *sysclk_idx = *dac_idx = *bclk_idx = -1;
- for (i = 0; i < ARRAY_SIZE(sysclk_divs); ++i) { + /* + * From Datasheet, the PLL performs best when f2 is between + * 90MHz and 100MHz, the desired sysclk output is 11.2896MHz + * or 12.288MHz, then sysclkdiv = 2 is the best choice. + * So search sysclk_divs from 2 to 1 other than from 1 to 2. + */ + for (i = ARRAY_SIZE(sysclk_divs) - 1; i >= 0; --i) { if (sysclk_divs[i] == -1) continue; for (j = 0; j < ARRAY_SIZE(dac_divs); ++j) {