ASoC: Add a cache_sync bit to the CODEC structure

Add a bit to the CODEC structure indicating if a cache sync is required.
By default this will be set if a cache only write is done to a soc-cache
register cache.  This allows us to avoid syncing the cache back after
using cache only writes if there were no changes.

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

2 files changed, 16 insertions, 5 deletions

diff --git a/include/sound/soc.h b/include/sound/soc.h
index 4e8f14bc8ed3..e6a6d10de1d3 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -424,6 +424,7 @@ struct snd_soc_codec {
 
         unsigned int idle_bias_off:1; /* Use BIAS_OFF instead of STANDBY */
         unsigned int cache_only:1;  /* Suppress writes to hardware */
+        unsigned int cache_sync:1; /* Cache needs to be synced to hardware */
 
         /* dapm */
         u32 pop_time;
diff --git a/sound/soc/soc-cache.c b/sound/soc/soc-cache.c
index 84b6916db87d..5869dc3be781 100644
--- a/sound/soc/soc-cache.c
+++ b/sound/soc/soc-cache.c
@@ -39,8 +39,10 @@ static int snd_soc_4_12_write(struct snd_soc_codec *codec, unsigned int reg,
         if (reg < codec->reg_cache_size)
                 cache[reg] = value;
 
-        if (codec->cache_only)
+        if (codec->cache_only) {
+                codec->cache_sync = 1;
                 return 0;
+        }
 
         ret = codec->hw_write(codec->control_data, data, 2);
         if (ret == 2)
@@ -105,8 +107,10 @@ static int snd_soc_7_9_write(struct snd_soc_codec *codec, unsigned int reg,
         if (reg < codec->reg_cache_size)
                 cache[reg] = value;
 
-        if (codec->cache_only)
+        if (codec->cache_only) {
+                codec->cache_sync = 1;
                 return 0;
+        }
 
         ret = codec->hw_write(codec->control_data, data, 2);
         if (ret == 2)
@@ -161,8 +165,10 @@ static int snd_soc_8_8_write(struct snd_soc_codec *codec, unsigned int reg,
         if (reg < codec->reg_cache_size)
                 cache[reg] = value;
 
-        if (codec->cache_only)
+        if (codec->cache_only) {
+                codec->cache_sync = 1;
                 return 0;
+        }
 
         if (codec->hw_write(codec->control_data, data, 2) == 2)
                 return 0;
@@ -192,8 +198,10 @@ static int snd_soc_8_16_write(struct snd_soc_codec *codec, unsigned int reg,
         if (!snd_soc_codec_volatile_register(codec, reg))
                 reg_cache[reg] = value;
 
-        if (codec->cache_only)
+        if (codec->cache_only) {
+                codec->cache_sync = 1;
                 return 0;
+        }
 
         if (codec->hw_write(codec->control_data, data, 3) == 3)
                 return 0;
@@ -313,8 +321,10 @@ static int snd_soc_16_8_write(struct snd_soc_codec *codec, unsigned int reg,
         if (reg < codec->reg_cache_size)
                 cache[reg] = value;
 
-        if (codec->cache_only)
+        if (codec->cache_only) {
+                codec->cache_sync = 1;
                 return 0;
+        }
 
         ret = codec->hw_write(codec->control_data, data, 3);
         if (ret == 3)