i2c: Add support for nested i2c bus locking
This patch adds the 'level' field into the i2c_adapter structure, which is
used to represent the 'logical' level of nesting for the purposes of
lockdep. This field is then used in the i2c_transfer() function, to
acquire the per-adapter bus_lock with correct nesting level.
Signed-off-by: Jiri Kosina <jikos@jikos.cz>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 9b5d047..08df416 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -216,6 +216,7 @@
int (*client_unregister)(struct i2c_client *);
/* data fields that are valid for all devices */
+ u8 level; /* nesting level for lockdep */
struct mutex bus_lock;
struct mutex clist_lock;