ASoC: soc-cache: Use BUG_ON() for unsupported hw_read() calls

Instead of dereferencing a NULL function pointer and falling apart
use BUG_ON() for any unimplemented hw_read() calls.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/sound/soc/soc-cache.c b/sound/soc/soc-cache.c
index 8785a0c918d2..e7479988deca 100644
--- a/sound/soc/soc-cache.c
+++ b/sound/soc/soc-cache.c
@@ -25,6 +25,7 @@ static unsigned int snd_soc_4_12_read(struct snd_soc_codec *codec,
                         if (codec->cache_only)
                                 return -1;
 
+                        BUG_ON(!codec->hw_read);
                         return codec->hw_read(codec, reg);
         }
 
@@ -99,6 +100,7 @@ static unsigned int snd_soc_7_9_read(struct snd_soc_codec *codec,
                         if (codec->cache_only)
                                 return -1;
 
+                        BUG_ON(!codec->hw_read);
                         return codec->hw_read(codec, reg);
         }
 
@@ -199,6 +201,7 @@ static unsigned int snd_soc_8_8_read(struct snd_soc_codec *codec,
                         if (codec->cache_only)
                                 return -1;
 
+                        BUG_ON(!codec->hw_read);
                         return codec->hw_read(codec, reg);
         }
 
@@ -270,6 +273,7 @@ static unsigned int snd_soc_8_16_read(struct snd_soc_codec *codec,
                 if (codec->cache_only)
                         return -1;
 
+                BUG_ON(!codec->hw_read);
                 return codec->hw_read(codec, reg);
         } else {
                 return cache[reg];
@@ -420,6 +424,7 @@ static unsigned int snd_soc_16_8_read(struct snd_soc_codec *codec,
                         if (codec->cache_only)
                                 return -1;
 
+                        BUG_ON(!codec->hw_read);
                         return codec->hw_read(codec, reg);
         }
 
@@ -531,6 +536,7 @@ static unsigned int snd_soc_16_16_read(struct snd_soc_codec *codec,
                 if (codec->cache_only)
                         return -1;
 
+                BUG_ON(!codec->hw_read);
                 return codec->hw_read(codec, reg);
         }