regmap: add regmap_write_bits()

regmap_write_bits() is similar to regmap_update_bits(),
but regmap_write_bits() write data to register even though
it is same value.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/base/regmap/regmap.c

@@ -2374,6 +2374,29 @@ int regmap_update_bits(struct regmap *map, unsigned int reg,
 }
 EXPORT_SYMBOL_GPL(regmap_update_bits);
 
+/**
+ * regmap_write_bits: Perform a read/modify/write cycle on the register map
+ *
+ * @map: Register map to update
+ * @reg: Register to update
+ * @mask: Bitmask to change
+ * @val: New value for bitmask
+ *
+ * Returns zero for success, a negative number on error.
+ */
+int regmap_write_bits(struct regmap *map, unsigned int reg,
+		      unsigned int mask, unsigned int val)
+{
+	int ret;
+
+	map->lock(map->lock_arg);
+	ret = _regmap_update_bits(map, reg, mask, val, NULL, true);
+	map->unlock(map->lock_arg);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_write_bits);
+
 /**
  * regmap_update_bits_async: Perform a read/modify/write cycle on the register
  *                           map asynchronously

include/linux/regmap.h

@@ -424,6 +424,8 @@ int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
 		     size_t val_count);
 int regmap_update_bits(struct regmap *map, unsigned int reg,
 		       unsigned int mask, unsigned int val);
+int regmap_write_bits(struct regmap *map, unsigned int reg,
+		       unsigned int mask, unsigned int val);
 int regmap_update_bits_async(struct regmap *map, unsigned int reg,
 			     unsigned int mask, unsigned int val);
 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
@@ -645,6 +647,13 @@ static inline int regmap_update_bits(struct regmap *map, unsigned int reg,
 	return -EINVAL;
 }
 
+static inline int regmap_write_bits(struct regmap *map, unsigned int reg,
+				     unsigned int mask, unsigned int val)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
 static inline int regmap_update_bits_async(struct regmap *map,
 					   unsigned int reg,
 					   unsigned int mask, unsigned int val)