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authorJon Ringle <jringle@gridpoint.com>2015-10-01 19:38:07 +0300
committerMark Brown <broonie@kernel.org>2015-10-06 18:12:34 +0300
commit77792b11409c9270d98e604b4314b85ce886ac7d (patch)
tree13f3a518de69bbbccbd410b26ff24f0379c28dfd /drivers/base
parent6ff33f3902c3b1c5d0db6b1e2c70b6d76fba357f (diff)
downloadlinux-77792b11409c9270d98e604b4314b85ce886ac7d.tar.xz
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 <jringle@gridpoint.com> Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/base')
-rw-r--r--drivers/base/regmap/internal.h2
-rw-r--r--drivers/base/regmap/regmap.c29
2 files changed, 20 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;