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ASoC: cs35l56: ASP1 DOUT must default to Hi-Z when not transmitting

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The ASP1 DOUT line must be defaulted to be high-impedance when
it is not actually transmitting data for an active channel.

In non-SoundWire modes ASP1 will usually be shared by multiple
amps so each amp must only drive the line during the slot for
an enabled TX channel.

In SoundWire mode a custom firmware can use ASP1 as a secondary
chip-to-chip audio link or as GPIO. It should be defaulted to
high-impedance since by default the purpose of this pin is not
known.

Backport note:
On kernel versions before 6.6 the cs35l56->base.regmap argument
to regmap_set_bits() must be changed to cs35l56->regmap.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: e49611252900 ("ASoC: cs35l56: Add driver for Cirrus Logic CS35L56")
Link: https://lore.kernel.org/r/20231009153412.30380-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Richard Fitzgerald 2023-10-09 16:34:12 +01:00 committed by Mark Brown
parent cc660a4a8e
commit 1bba0badff
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1 changed files with 6 additions and 0 deletions
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6
sound/soc/codecs/cs35l56.c
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@ -1186,6 +1186,12 @@ post_soft_reset:
/* Registers could be dirty after soft reset or SoundWire enumeration */
regcache_sync(cs35l56->base.regmap);
/* Set ASP1 DOUT to high-impedance when it is not transmitting audio data. */
ret = regmap_set_bits(cs35l56->base.regmap, CS35L56_ASP1_CONTROL3,
CS35L56_ASP1_DOUT_HIZ_CTRL_MASK);
if (ret)
return dev_err_probe(cs35l56->base.dev, ret, "Failed to write ASP1_CONTROL3\n");
cs35l56->base.init_done = true;
complete(&cs35l56->init_completion);