regmap: prevent division by zero in rbtree_show
Stephen Warren [Wed, 4 Apr 2012 21:48:33 +0000 (15:48 -0600)]
If there are no nodes in the cache, nodes will be 0, so calculating
"registers / nodes" will cause division by zero.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@vger.kernel.org
(cherry picked from commit c04c1b9ee8f30c7a3a25e20e406247003f634ebe)

Change-Id: I30047f1e0bd08417794c3d19e2fe1d480a74e083
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-on: http://git-master/r/96501
Reviewed-by: Simone Willett <swillett@nvidia.com>
Tested-by: Simone Willett <swillett@nvidia.com>

drivers/base/regmap/regcache-rbtree.c

index 5157fa0..ea76a90 100644 (file)
@@ -138,6 +138,7 @@ static int rbtree_show(struct seq_file *s, void *ignored)
        unsigned int base, top;
        int nodes = 0;
        int registers = 0;
+       int average;
 
        mutex_lock(&map->lock);
 
@@ -152,8 +153,13 @@ static int rbtree_show(struct seq_file *s, void *ignored)
                registers += top - base + 1;
        }
 
+       if (nodes)
+               average = registers / nodes;
+       else
+               average = 0;
+
        seq_printf(s, "%d nodes, %d registers, average %d registers\n",
-                  nodes, registers, registers / nodes);
+                  nodes, registers, average);
 
        mutex_unlock(&map->lock);