From c9b41fcf272b4926b373d21c2b83dfe374313780 Mon Sep 17 00:00:00 2001 From: Bartosz Golaszewski Date: Wed, 6 Dec 2017 15:26:21 +0100 Subject: regmap: allow to disable all locking mechanisms We have a use case in the at24 EEPROM driver (recently converted to using regmap instead of raw i2c/smbus calls) where we read from/write to the regmap in a loop, while protecting the entire loop with a mutex. Currently this implicitly makes us use two mutexes - one in the driver and one in regmap. While browsing the code for similar use cases I noticed a significant number of places where locking *seems* redundant. Allow users to completely disable any locking mechanisms in regmap config. Signed-off-by: Bartosz Golaszewski Signed-off-by: Mark Brown --- include/linux/regmap.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux/regmap.h') diff --git a/include/linux/regmap.h b/include/linux/regmap.h index 15eddc1353ba..072a90229e34 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -264,6 +264,9 @@ typedef void (*regmap_unlock)(void *); * field is NULL but precious_table (see below) is not, the * check is performed on such table (a register is precious if * it belongs to one of the ranges specified by precious_table). + * @disable_locking: This regmap is either protected by external means or + * is guaranteed not be be accessed from multiple threads. + * Don't use any locking mechanisms. * @lock: Optional lock callback (overrides regmap's default lock * function, based on spinlock or mutex). * @unlock: As above for unlocking. @@ -333,6 +336,8 @@ 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); + + bool disable_locking; regmap_lock lock; regmap_unlock unlock; void *lock_arg; -- cgit v1.2.3