[PATCH] ASoC: wm8904: fix regcache handling

From: Michael Walle
Date: Tue Nov 12 2019 - 17:36:50 EST


The current code assumes that the power is turned off in
SND_SOC_BIAS_OFF. If there are no actual regulator the codec isn't
turned off and the registers are not reset to their default values but
the regcache is still marked as dirty. Thus a value might not be written
to the hardware if it is set to the default value. Do a software reset
before turning off the power to make sure the registers are always reset
to their default states.

Signed-off-by: Michael Walle <michael@xxxxxxxx>
---
sound/soc/codecs/wm8904.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/sound/soc/codecs/wm8904.c b/sound/soc/codecs/wm8904.c
index 2a7d23a5daa8..7d7ea15d73e0 100644
--- a/sound/soc/codecs/wm8904.c
+++ b/sound/soc/codecs/wm8904.c
@@ -1933,6 +1933,7 @@ static int wm8904_set_bias_level(struct snd_soc_component *component,
snd_soc_component_update_bits(component, WM8904_BIAS_CONTROL_0,
WM8904_BIAS_ENA, 0);

+ snd_soc_component_write(component, WM8904_SW_RESET_AND_ID, 0);
regcache_cache_only(wm8904->regmap, true);
regcache_mark_dirty(wm8904->regmap);

--
2.20.1