mtd: docg3 add protection against concurrency
As docg3 is intolerant against reentrancy, especially
because of its weird register access (ie. a register read is
performed by a first register write), each access to the
docg3 IO space must be locked.
Lock the IO space with a mutex, shared by all chips on the
same cascade, as they all share the same IO space.
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/devices/docg3.h b/drivers/mtd/devices/docg3.h
index 642e606..19fb93f 100644
--- a/drivers/mtd/devices/docg3.h
+++ b/drivers/mtd/devices/docg3.h
@@ -273,11 +273,13 @@
* @floors: floors (ie. one physical docg3 chip is one floor)
* @base: IO space to access all chips in the cascade
* @bch: the BCH correcting control structure
+ * @lock: lock to protect docg3 IO space from concurrent accesses
*/
struct docg3_cascade {
struct mtd_info *floors[DOC_MAX_NBFLOORS];
void __iomem *base;
struct bch_control *bch;
+ struct mutex lock;
};
/**