summaryrefslogtreecommitdiff
path: root/drivers/i2c
diff options
context:
space:
mode:
authorBartosz Golaszewski <bgolaszewski@baylibre.com>2016-09-16 18:02:44 +0200
committerWolfram Sang <wsa@the-dreams.de>2016-09-24 10:50:00 +0200
commit2771dc34ddaa313127d6431f23ae4cea26b869b0 (patch)
tree94baef22dc81107ef9c081e75554dbe090474f67 /drivers/i2c
parenta5ecddfe0bf82c92cc2e47385e287b21361a8d70 (diff)
i2c: add a warning to i2c_adapter_depth()
This routine is only used together with lockdep for nested locking. The number of lock subclasses is limited to 8 as defined in lockdep.h Emit a warning if the adapter depth exceeds the maximum number of lockdep subclasses. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Acked-by: Peter Rosin <peda@axentia.se> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/i2c-core.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 981de21ab814..98fffa3a09f7 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1433,6 +1433,9 @@ unsigned int i2c_adapter_depth(struct i2c_adapter *adapter)
while ((adapter = i2c_parent_is_i2c_adapter(adapter)))
depth++;
+ WARN_ONCE(depth >= MAX_LOCKDEP_SUBCLASSES,
+ "adapter depth exceeds lockdep subclass limit\n");
+
return depth;
}
EXPORT_SYMBOL_GPL(i2c_adapter_depth);