regmap: Bypass the cache when applying patches

Otherwise any patch that affects a register which is writable may trash
cached values.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index 9c6a5c1..ee36bed 100644 (file)
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -273,6 +273,7 @@ int regcache_sync(struct regmap *map)
                goto out;
 
        /* Apply any patch first */
+       map->cache_bypass = 1;
        for (i = 0; i < map->patch_regs; i++) {
                ret = _regmap_write(map, map->patch[i].reg, map->patch[i].def);
                if (ret != 0) {
@@ -281,6 +282,7 @@ int regcache_sync(struct regmap *map)
                        goto out;
                }
        }
+       map->cache_bypass = 0;
 
        if (map->cache_ops->sync) {
                ret = map->cache_ops->sync(map);