[PATCH v2] regmap: Don't lock in regmap_reinit_cache()

From: Dimitris Papastamos
Date: Fri Jul 27 2012 - 09:54:10 EST


When bus->fast_io is set, the locking here is done with spinlocks.
This is currently true for the regmap-mmio bus implementation.

While holding a spinlock we can't go to sleep, various operations
like removing the debugfs entries or re-initializing the cache will
sleep, therefore, shift the locking up to the user.

Signed-off-by: Dimitris Papastamos <dp@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
---
V2, removed the change id that was automatically.

drivers/base/regmap/regmap.c | 13 ++++---------
1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index c241ae2..52069d2 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -659,13 +659,12 @@ EXPORT_SYMBOL_GPL(devm_regmap_init);
* new cache. This can be used to restore the cache to defaults or to
* update the cache configuration to reflect runtime discovery of the
* hardware.
+ *
+ * No explicit locking is done here, the user needs to ensure that
+ * this function will not race with other calls to regmap.
*/
int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config)
{
- int ret;
-
- map->lock(map);
-
regcache_exit(map);
regmap_debugfs_exit(map);

@@ -681,11 +680,7 @@ int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config)
map->cache_bypass = false;
map->cache_only = false;

- ret = regcache_init(map, config);
-
- map->unlock(map);
-
- return ret;
+ return regcache_init(map, config);
}
EXPORT_SYMBOL_GPL(regmap_reinit_cache);

--
1.7.11.3

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