[PATCH 3/3] ASoC: soc-cache: Ignore !codec->writable_register() during syncing

[Dimitris Papastamos <dp@opensource.wolfsonmicro.com>]

When syncing the cache, if the driver has given us a writable_register()
callback, use it to not sync any non-writable registers.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
---
 sound/soc/soc-cache.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/sound/soc/soc-cache.c b/sound/soc/soc-cache.c
index 657889d..0ec8e13 100644
--- a/sound/soc/soc-cache.c
+++ b/sound/soc/soc-cache.c
@@ -889,6 +889,9 @@ static int snd_soc_rbtree_cache_sync(struct snd_soc_codec *codec)
 		rbnode = rb_entry(node, struct snd_soc_rbtree_node, node);
 		if (rbnode->value == rbnode->defval)
 			continue;
+		if (codec->writable_register &&
+		    !codec->writable_register(codec, rbnode->reg))
+			continue;
 		ret = snd_soc_cache_read(codec, rbnode->reg, &val);
 		if (ret)
 			return ret;
@@ -1149,6 +1152,8 @@ static int snd_soc_lzo_cache_sync(struct snd_soc_codec *codec)
 
 	lzo_blocks = codec->reg_cache;
 	for_each_set_bit(i, lzo_blocks[0]->sync_bmp, lzo_blocks[0]->sync_bmp_nbits) {
+		if (codec->writable_register && !codec->writable_register(codec, i))
+			continue;
 		ret = snd_soc_cache_read(codec, i, &val);
 		if (ret)
 			return ret;
@@ -1407,6 +1412,8 @@ static int snd_soc_flat_cache_sync(struct snd_soc_codec *codec)
 
 	codec_drv = codec->driver;
 	for (i = 0; i < codec_drv->reg_cache_size; ++i) {
+		if (codec->writable_register && !codec->writable_register(codec, i))
+			continue;
 		ret = snd_soc_cache_read(codec, i, &val);
 		if (ret)
 			return ret;
-- 
1.7.4.1