[PATCH 1/3] ASoC: tlv320aic32x4: Ensure a minimum delay before clock stabilization

Miquel Raynal
2020-09-11T17:32:07Z

As indicated in the datasheet, a 10ms delay must be observed after
programming the divisors.

The lack of delay prevents the codec to work properly and the playback
appears extremely slow and totally un-audible on a custom sama5 based
board.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
sound/soc/codecs/tlv320aic32x4-clk.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/sound/soc/codecs/tlv320aic32x4-clk.c b/sound/soc/codecs/tlv320aic32x4-clk.c
index 156c153c12ab..2f78e6820c75 100644
--- a/sound/soc/codecs/tlv320aic32x4-clk.c
+++ b/sound/soc/codecs/tlv320aic32x4-clk.c
@@ -230,7 +230,14 @@ static int clk_aic32x4_pll_set_rate(struct clk_hw *hw,
if (ret < 0)
return -EINVAL;

- return clk_aic32x4_pll_set_muldiv(pll, &settings);
+ ret = clk_aic32x4_pll_set_muldiv(pll, &settings);
+ if (ret)
+ return ret;
+
+ /* 10ms is the delay to wait before the clocks are stable */
+ msleep(10);
+
+ return 0;
}

static int clk_aic32x4_pll_set_parent(struct clk_hw *hw, u8 index)
--
2.20.1