From 77792b11409c9270d98e604b4314b85ce886ac7d Mon Sep 17 00:00:00 2001 From: Jon Ringle Date: Thu, 1 Oct 2015 12:38:07 -0400 Subject: [PATCH] regmap: Allow installing custom reg_update_bits function This commit allows installing a custom reg_update_bits function for cases where the hardware provides a mechanism to set or clear register bits without a read/modify/write cycle. Such is the case with the Microchip ENCX24J600. If a custom reg_update_bits function is provided, it will only be used against volatile registers. Signed-off-by: Jon Ringle Signed-off-by: Mark Brown --- drivers/base/regmap/internal.h | 2 ++ drivers/base/regmap/regmap.c | 29 ++++++++++++++++++----------- include/linux/regmap.h | 3 +++ 3 files changed, 23 insertions(+), 11 deletions(-) diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h index cc557886ab23..628ad7ac078b 100644 --- a/drivers/base/regmap/internal.h +++ b/drivers/base/regmap/internal.h @@ -98,6 +98,8 @@ struct regmap { int (*reg_read)(void *context, unsigned int reg, unsigned int *val); int (*reg_write)(void *context, unsigned int reg, unsigned int val); + int (*reg_update_bits)(void *context, unsigned int reg, + unsigned int mask, unsigned int val); bool defer_caching; diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index afaf56200674..8cd155af3d63 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -619,6 +619,7 @@ struct regmap *__regmap_init(struct device *dev, goto skip_format_initialization; } else { map->reg_read = _regmap_bus_read; + map->reg_update_bits = bus->reg_update_bits; } reg_endian = regmap_get_reg_endian(bus, config); @@ -2509,20 +2510,26 @@ static int _regmap_update_bits(struct regmap *map, unsigned int reg, int ret; unsigned int tmp, orig; - ret = _regmap_read(map, reg, &orig); - if (ret != 0) - return ret; + if (change) + *change = false; - tmp = orig & ~mask; - tmp |= val & mask; - - if (force_write || (tmp != orig)) { - ret = _regmap_write(map, reg, tmp); - if (change) + if (regmap_volatile(map, reg) && map->reg_update_bits) { + ret = map->reg_update_bits(map->bus_context, reg, mask, val); + if (ret == 0 && change) *change = true; } else { - if (change) - *change = false; + ret = _regmap_read(map, reg, &orig); + if (ret != 0) + return ret; + + tmp = orig & ~mask; + tmp |= val & mask; + + if (force_write || (tmp != orig)) { + ret = _regmap_write(map, reg, tmp); + if (ret == 0 && change) + *change = true; + } } return ret; diff --git a/include/linux/regmap.h b/include/linux/regmap.h index 8fc0bfd8edc4..b49d4133750e 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -296,6 +296,8 @@ typedef int (*regmap_hw_reg_read)(void *context, unsigned int reg, unsigned int *val); typedef int (*regmap_hw_reg_write)(void *context, unsigned int reg, unsigned int val); +typedef int (*regmap_hw_reg_update_bits)(void *context, unsigned int reg, + unsigned int mask, unsigned int val); typedef struct regmap_async *(*regmap_hw_async_alloc)(void); typedef void (*regmap_hw_free_context)(void *context); @@ -335,6 +337,7 @@ struct regmap_bus { regmap_hw_gather_write gather_write; regmap_hw_async_write async_write; regmap_hw_reg_write reg_write; + regmap_hw_reg_update_bits reg_update_bits; regmap_hw_read read; regmap_hw_reg_read reg_read; regmap_hw_free_context free_context;