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regmap: Customisable lock functions

Browse source 
Allow maps to replace the lock function for integration with dynamic
 register accessability states.
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Merge tag 'lock' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap into for-next

regmap: Customisable lock functions

Allow maps to replace the lock function for integration with dynamic
register accessability states.
This commit is contained in:
Samuel Ortiz 2012-11-20 12:20:58 +01:00
commit 7aae79fd88
3 changed files with 54 additions and 31 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
drivers/base/regmap/internal.h
View file

@ -31,14 +31,12 @@ struct regmap_format {
unsigned int (*parse_val)(void *buf);
};
typedef void (*regmap_lock)(struct regmap *map);
typedef void (*regmap_unlock)(struct regmap *map);
struct regmap {
struct mutex mutex;
spinlock_t spinlock;
regmap_lock lock;
regmap_unlock unlock;
void *lock_arg; /* This is passed to lock/unlock functions */
struct device *dev; /* Device we do I/O on */
void *work_buf; /* Scratch buffer used to format I/O */

65
drivers/base/regmap/regmap.c
View file

@ -214,23 +214,27 @@ static unsigned int regmap_parse_32_native(void *buf)
return *(u32 *)buf;
}
static void regmap_lock_mutex(struct regmap *map)
static void regmap_lock_mutex(void *__map)
{
struct regmap *map = __map;
mutex_lock(&map->mutex);
}
static void regmap_unlock_mutex(struct regmap *map)
static void regmap_unlock_mutex(void *__map)
{
struct regmap *map = __map;
mutex_unlock(&map->mutex);
}
static void regmap_lock_spinlock(struct regmap *map)
static void regmap_lock_spinlock(void *__map)
{
struct regmap *map = __map;
spin_lock(&map->spinlock);
}
static void regmap_unlock_spinlock(struct regmap *map)
static void regmap_unlock_spinlock(void *__map)
{
struct regmap *map = __map;
spin_unlock(&map->spinlock);
}
@ -335,14 +339,21 @@ struct regmap *regmap_init(struct device *dev,
goto err;
}
if (bus->fast_io) {
spin_lock_init(&map->spinlock);
map->lock = regmap_lock_spinlock;
map->unlock = regmap_unlock_spinlock;
if (config->lock && config->unlock) {
map->lock = config->lock;
map->unlock = config->unlock;
map->lock_arg = config->lock_arg;
} else {
mutex_init(&map->mutex);
map->lock = regmap_lock_mutex;
map->unlock = regmap_unlock_mutex;
if (bus->fast_io) {
spin_lock_init(&map->spinlock);
map->lock = regmap_lock_spinlock;
map->unlock = regmap_unlock_spinlock;
} else {
mutex_init(&map->mutex);
map->lock = regmap_lock_mutex;
map->unlock = regmap_unlock_mutex;
}
map->lock_arg = map;
}
map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8);
map->format.pad_bytes = config->pad_bits / 8;
@ -939,11 +950,11 @@ int regmap_write(struct regmap *map, unsigned int reg, unsigned int val)
if (reg % map->reg_stride)
return -EINVAL;
map->lock(map);
map->lock(map->lock_arg);
ret = _regmap_write(map, reg, val);
map->unlock(map);
map->unlock(map->lock_arg);
return ret;
}
@ -975,11 +986,11 @@ int regmap_raw_write(struct regmap *map, unsigned int reg,
if (reg % map->reg_stride)
return -EINVAL;
map->lock(map);
map->lock(map->lock_arg);
ret = _regmap_raw_write(map, reg, val, val_len);
map->unlock(map);
map->unlock(map->lock_arg);
return ret;
}
@ -1011,7 +1022,7 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
if (reg % map->reg_stride)
return -EINVAL;
map->lock(map);
map->lock(map->lock_arg);
/* No formatting is require if val_byte is 1 */
if (val_bytes == 1) {
@ -1047,7 +1058,7 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
kfree(wval);
out:
map->unlock(map);
map->unlock(map->lock_arg);
return ret;
}
EXPORT_SYMBOL_GPL(regmap_bulk_write);
@ -1137,11 +1148,11 @@ int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val)
if (reg % map->reg_stride)
return -EINVAL;
map->lock(map);
map->lock(map->lock_arg);
ret = _regmap_read(map, reg, val);
map->unlock(map);
map->unlock(map->lock_arg);
return ret;
}
@ -1171,7 +1182,7 @@ int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
if (reg % map->reg_stride)
return -EINVAL;
map->lock(map);
map->lock(map->lock_arg);
if (regmap_volatile_range(map, reg, val_count) || map->cache_bypass ||
map->cache_type == REGCACHE_NONE) {
@ -1193,7 +1204,7 @@ int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
}
out:
map->unlock(map);
map->unlock(map->lock_arg);
return ret;
}
@ -1300,9 +1311,9 @@ int regmap_update_bits(struct regmap *map, unsigned int reg,
bool change;
int ret;
map->lock(map);
map->lock(map->lock_arg);
ret = _regmap_update_bits(map, reg, mask, val, &change);
map->unlock(map);
map->unlock(map->lock_arg);
return ret;
}
@ -1326,9 +1337,9 @@ int regmap_update_bits_check(struct regmap *map, unsigned int reg,
{
int ret;
map->lock(map);
map->lock(map->lock_arg);
ret = _regmap_update_bits(map, reg, mask, val, change);
map->unlock(map);
map->unlock(map->lock_arg);
return ret;
}
EXPORT_SYMBOL_GPL(regmap_update_bits_check);
@ -1357,7 +1368,7 @@ int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
if (map->patch)
return -EBUSY;
map->lock(map);
map->lock(map->lock_arg);
bypass = map->cache_bypass;
@ -1385,7 +1396,7 @@ int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
out:
map->cache_bypass = bypass;
map->unlock(map);
map->unlock(map->lock_arg);
return ret;
}

16
include/linux/regmap.h
View file

@ -54,6 +54,9 @@ enum regmap_endian {
REGMAP_ENDIAN_NATIVE,
};
typedef void (*regmap_lock)(void *);
typedef void (*regmap_unlock)(void *);
/**
* Configuration for the register map of a device.
*
@ -76,6 +79,12 @@ enum regmap_endian {
* @precious_reg: Optional callback returning true if the rgister
* should not be read outside of a call from the driver
* (eg, a clear on read interrupt status register).
* @lock: Optional lock callback (overrides regmap's default lock
* function, based on spinlock or mutex).
* @unlock: As above for unlocking.
* @lock_arg: this field is passed as the only argument of lock/unlock
* functions (ignored in case regular lock/unlock functions
* are not overridden).
*
* @max_register: Optional, specifies the maximum valid register index.
* @reg_defaults: Power on reset values for registers (for use with
@ -117,6 +126,9 @@ struct regmap_config {
bool (*readable_reg)(struct device *dev, unsigned int reg);
bool (*volatile_reg)(struct device *dev, unsigned int reg);
bool (*precious_reg)(struct device *dev, unsigned int reg);
regmap_lock lock;
regmap_unlock unlock;
void *lock_arg;
unsigned int max_register;
const struct reg_default *reg_defaults;
@ -182,7 +194,9 @@ typedef void (*regmap_hw_free_context)(void *context);
* Description of a hardware bus for the register map infrastructure.
*
* @fast_io: Register IO is fast. Use a spinlock instead of a mutex
* to perform locking.
* to perform locking. This field is ignored if custom lock/unlock
* functions are used (see fields lock/unlock of
* struct regmap_config).
* @write: Write operation.
* @gather_write: Write operation with split register/value, return -ENOTSUPP
* if not implemented on a given device.