regmap: introduce fast_io busses, and use a spinlock for them
Some bus types have very fast IO. For these, acquiring a mutex for every
IO operation is a significant overhead. Allow busses to indicate their IO
is fast, and enhance regmap to use a spinlock for those busses.
[Currently limited to native endian registers -- broonie]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index b95fd1f..e46c279 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -31,8 +31,14 @@
unsigned int (*parse_val)(void *buf);
};
+typedef void (*regmap_lock)(struct regmap *map);
+typedef void (*regmap_unlock)(struct regmap *map);
+
struct regmap {
- struct mutex lock;
+ struct mutex mutex;
+ spinlock_t spinlock;
+ regmap_lock lock;
+ regmap_unlock unlock;
struct device *dev; /* Device we do I/O on */
void *work_buf; /* Scratch buffer used to format I/O */