diff options
| -rw-r--r-- | drivers/base/regmap/regmap.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index e533368e5598..10ecbba32e10 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -583,18 +583,19 @@ int regmap_update_bits(struct regmap *map, unsigned int reg, unsigned int mask, unsigned int val) { int ret; - unsigned int tmp; + unsigned int tmp, orig; mutex_lock(&map->lock); - ret = _regmap_read(map, reg, &tmp); + ret = _regmap_read(map, reg, &orig); if (ret != 0) goto out; - tmp &= ~mask; + tmp = orig & ~mask; tmp |= val & mask; - ret = _regmap_write(map, reg, tmp); + if (tmp != orig) + ret = _regmap_write(map, reg, tmp); out: mutex_unlock(&map->lock); |