Some device drivers using the register map API need to copy the value from one register to another. Even though it can be done with a combination of regmap_read() and regmap_write(), it is better to have a function to avoid code duplication, sanity check passed values and do it atomically by holding the regmap lock. Signed-off-by: Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx> --- drivers/base/regmap/regmap.c | 34 ++++++++++++++++++++++++++++++++++ include/linux/regmap.h | 9 +++++++++ 2 files changed, 43 insertions(+) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 74d8c06..a2e0b04 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -2555,6 +2555,40 @@ int regmap_parse_val(struct regmap *map, const void *buf, } EXPORT_SYMBOL_GPL(regmap_parse_val); +/** + * regmap_reg_copy(): Copy a value from a single register to another one + * + * @map: Register map to operate on + * @dest: Register to copy the value to + * @src: Register to copy the value from + * + * A value of zero will be returned on success, a negative errno will + * be returned in error cases. + */ +int regmap_reg_copy(struct regmap *map, unsigned int dest, unsigned int src) +{ + int val; + int ret = 0; + + if (dest == src) + return ret; + + if (dest % map->reg_stride || + src % map->reg_stride) + return -EINVAL; + + map->lock(map->lock_arg); + + ret = _regmap_read(map, src, &val); + if (!ret) + ret = _regmap_write(map, dest, val); + + map->unlock(map->lock_arg); + + return ret; +} +EXPORT_SYMBOL_GPL(regmap_reg_copy); + static int __init regmap_initcall(void) { regmap_debugfs_initcall(); diff --git a/include/linux/regmap.h b/include/linux/regmap.h index 7b0e4b4..116c22b 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -445,6 +445,8 @@ int regmap_register_patch(struct regmap *map, const struct reg_default *regs, int regmap_parse_val(struct regmap *map, const void *buf, unsigned int *val); +int regmap_reg_copy(struct regmap *map, unsigned int dest, unsigned int src); + static inline bool regmap_reg_in_range(unsigned int reg, const struct regmap_range *range) { @@ -723,6 +725,13 @@ static inline int regmap_parse_val(struct regmap *map, const void *buf, return -EINVAL; } +static inline int regmap_reg_copy(struct regmap *map, unsigned int dest, + unsigned int src) +{ + WARN_ONCE(1, "regmap API is disabled"); + return -EINVAL; +} + static inline struct regmap *dev_get_regmap(struct device *dev, const char *name) { -- 2.0.0.rc2 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html