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regmap: Allow installing custom reg_update_bits function

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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>
This commit is contained in:
Jon Ringle 2015-10-01 12:38:07 -04:00 committed by Mark Brown
parent 6ff33f3902
commit 77792b1140
3 changed files with 23 additions and 11 deletions
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2
drivers/base/regmap/internal.h
View File

@ -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;

29
drivers/base/regmap/regmap.c
View File

@ -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;

3
include/linux/regmap.h
View File

@ -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;