diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c index aec5a7486a29..b35f8751471d 100644 --- a/drivers/base/regmap/regcache.c +++ b/drivers/base/regmap/regcache.c @@ -298,6 +298,51 @@ int regcache_sync(struct regmap *map) } EXPORT_SYMBOL_GPL(regcache_sync); +/** + * regcache_sync_region: Sync part of the register cache with the hardware. + * + * @map: map to sync. + * @min: first register to sync + * @max: last register to sync + * + * Write all non-default register values in the specified region to + * the hardware. + * + * Return a negative value on failure, 0 on success. + */ +int regcache_sync_region(struct regmap *map, unsigned int min, + unsigned int max) +{ + int ret = 0; + const char *name; + unsigned int bypass; + + BUG_ON(!map->cache_ops || !map->cache_ops->sync); + + mutex_lock(&map->lock); + + /* Remember the initial bypass state */ + bypass = map->cache_bypass; + + name = map->cache_ops->name; + dev_dbg(map->dev, "Syncing %s cache from %d-%d\n", name, min, max); + + trace_regcache_sync(map->dev, name, "start region"); + + if (!map->cache_dirty) + goto out; + + ret = map->cache_ops->sync(map, min, max); + +out: + trace_regcache_sync(map->dev, name, "stop region"); + /* Restore the bypass state */ + map->cache_bypass = bypass; + mutex_unlock(&map->lock); + + return ret; +} + /** * regcache_cache_only: Put a register map into cache only mode * diff --git a/include/linux/regmap.h b/include/linux/regmap.h index 860739a8a6dd..5ff7d44730e5 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -145,6 +145,8 @@ int regmap_update_bits_check(struct regmap *map, unsigned int reg, bool *change); int regcache_sync(struct regmap *map); +int regcache_sync_region(struct regmap *map, unsigned int min, + unsigned int max); void regcache_cache_only(struct regmap *map, bool enable); void regcache_cache_bypass(struct regmap *map, bool enable); void regcache_mark_dirty(struct regmap *map);