ASoC: fixes to caching implementations

This patch takes fixes a number of bugs in the caching code used by
several ASoC codec drivers. Mostly off-by-one fixes.

Signed-off-by: Ian Molton <ian@mnementh.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/sound/soc/codecs/twl4030.c b/sound/soc/codecs/twl4030.c
index ddc9f37d863f..f530c1e6d9e8 100644
--- a/sound/soc/codecs/twl4030.c
+++ b/sound/soc/codecs/twl4030.c
@@ -125,6 +125,9 @@ static inline unsigned int twl4030_read_reg_cache(struct snd_soc_codec *codec,
 {
         u8 *cache = codec->reg_cache;
 
+        if (reg >= TWL4030_CACHEREGNUM)
+                return -EIO;
+
         return cache[reg];
 }