Commit 0d4529c5 authored by Davide Ciminaghi's avatar Davide Ciminaghi Committed by Mark Brown
Browse files

regmap: make lock/unlock functions customizable 



It is sometimes convenient for a regmap user to override the standard
regmap lock/unlock functions with custom functions.
For instance this can be useful in case an already existing spinlock
or mutex has to be used for locking a set of registers instead of the
internal regmap spinlock/mutex.
Note that the fast_io field of struct regmap_bus is ignored in case
custom locking functions are used.

Signed-off-by: default avatarDavide Ciminaghi <ciminaghi@gnudd.com>
Signed-off-by: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
parent ddffeb8c

drivers/base/regmap/internal.h

+1 −3
Original line number Diff line number Diff line
@@ -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 */

drivers/base/regmap/regmap.c

+38 −27
Original line number Diff line number Diff line
@@ -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);

}
@@ -335,6 +339,11 @@ struct regmap *regmap_init(struct device *dev, 
		goto err;

	}



	if (config->lock && config->unlock) {

		map->lock = config->lock;

		map->unlock = config->unlock;

		map->lock_arg = config->lock_arg;

	} else {

		if (bus->fast_io) {

			spin_lock_init(&map->spinlock);

			map->lock = regmap_lock_spinlock;
@@ -344,6 +353,8 @@ struct regmap *regmap_init(struct device *dev, 
			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;

	map->format.val_bytes = DIV_ROUND_UP(config->val_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;

}

include/linux/regmap.h

+15 −1
Original line number Diff line number Diff line
@@ -53,6 +53,9 @@ enum regmap_endian { 
	REGMAP_ENDIAN_NATIVE,

};



typedef void (*regmap_lock)(void *);

typedef void (*regmap_unlock)(void *);



/**

 * Configuration for the register map of a device.

 *
@@ -75,6 +78,12 @@ 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
@@ -116,6 +125,9 @@ 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;
@@ -181,7 +193,9 @@ 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.

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