[PATCH] ASoC: mediatek: mt8195: update audio tuner settings

Trevor Wu trevor.wu at mediatek.com
Tue Sep 27 08:11:41 PDT 2022


Audio tuner is used to handle clock drift between 26M and APLL domain.

It's expected when abs(chg_cnt) equals to upper bound, tuner updates pcw
setting automatically, and then abs(chg_cnt) decreases.
In the stress test, we found abs(chg_cnt) possibly equals to 2 at the
unexpected timing. This results in wrong pcw updating.
Finally, abs(chg_cnt) will always be larger than upper bound,

As a result, we update the upper bound to 3 to handle the corner case.

Signed-off-by: Trevor Wu <trevor.wu at mediatek.com>
---
 sound/soc/mediatek/mt8195/mt8195-afe-clk.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sound/soc/mediatek/mt8195/mt8195-afe-clk.c b/sound/soc/mediatek/mt8195/mt8195-afe-clk.c
index 2ee3872c83c3..9ca2cb8c8a9c 100644
--- a/sound/soc/mediatek/mt8195/mt8195-afe-clk.c
+++ b/sound/soc/mediatek/mt8195/mt8195-afe-clk.c
@@ -117,7 +117,7 @@ static struct mt8195_afe_tuner_cfg mt8195_afe_tuner_cfgs[MT8195_AUD_PLL_NUM] = {
 		.upper_bound_reg = AFE_APLL_TUNER_CFG,
 		.upper_bound_shift = 8,
 		.upper_bound_maskbit = 0xff,
-		.upper_bound_default = 0x2,
+		.upper_bound_default = 0x3,
 	},
 	[MT8195_AUD_PLL2] = {
 		.id = MT8195_AUD_PLL2,
@@ -135,7 +135,7 @@ static struct mt8195_afe_tuner_cfg mt8195_afe_tuner_cfgs[MT8195_AUD_PLL_NUM] = {
 		.upper_bound_reg = AFE_APLL_TUNER_CFG1,
 		.upper_bound_shift = 8,
 		.upper_bound_maskbit = 0xff,
-		.upper_bound_default = 0x2,
+		.upper_bound_default = 0x3,
 	},
 	[MT8195_AUD_PLL3] = {
 		.id = MT8195_AUD_PLL3,
-- 
2.18.0




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