[PATCH 4.4 042/114] ASoC: ak4613: Enable cache usage to fix crashes on resume

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit dcd2d1f78664fdc75eadaaf65257834e24383d01 ]

During system resume:

    kernel BUG at drivers/base/regmap/regcache.c:347!
    ...
    PC is at regcache_sync+0x1c/0x128
    LR is at ak4613_resume+0x28/0x34

The ak4613 driver is using a regmap cache sync to restore the
configuration of the chip on resume but does not actually define a
register cache which means that the resume 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@xxxxxxxxxx>.

Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 sound/soc/codecs/ak4613.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sound/soc/codecs/ak4613.c b/sound/soc/codecs/ak4613.c
index 07a266460ec3..b4b36cc92ffe 100644
--- a/sound/soc/codecs/ak4613.c
+++ b/sound/soc/codecs/ak4613.c
@@ -143,6 +143,7 @@ static const struct regmap_config ak4613_regmap_cfg = {
 	.max_register		= 0x16,
 	.reg_defaults		= ak4613_reg,
 	.num_reg_defaults	= ARRAY_SIZE(ak4613_reg),
+	.cache_type		= REGCACHE_RBTREE,
 };
 
 static const struct of_device_id ak4613_of_match[] = {
-- 
2.17.1