[alsa-devel] [PATCH 3/3] ASoC: wm8940: Enable cache usage to fix crashes on resume

[Geert Uytterhoeven]

The wm8940 driver is using a regmap cache sync to restore the
configuration of the chip when switching from OFF to STANDBY, but does
not actually define a register cache which means that the restore is
never going to work and we trigger asserts in regmap.  Fix this by
enabling caching.

Based on commit d3030d11961a8c10 ("ASoC: ak4642: Enable cache usage to
fix crashes on resume") by Mark Brown <broonie at kernel.org>.

Signed-off-by: Geert Uytterhoeven <geert+renesas at glider.be>
---
Untested.
---
 sound/soc/codecs/wm8940.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sound/soc/codecs/wm8940.c b/sound/soc/codecs/wm8940.c
index f6f9395ea38ef88b..1c600819f7689b45 100644
--- a/sound/soc/codecs/wm8940.c
+++ b/sound/soc/codecs/wm8940.c
@@ -743,6 +743,7 @@ static const struct regmap_config wm8940_regmap = {
 	.max_register = WM8940_MONOMIX,
 	.reg_defaults = wm8940_reg_defaults,
 	.num_reg_defaults = ARRAY_SIZE(wm8940_reg_defaults),
+	.cache_type = REGCACHE_RBTREE,
 
 	.readable_reg = wm8940_readable_register,
 	.volatile_reg = wm8940_volatile_register,
-- 
1.9.1