regmap: debugfs: Discard the cache if we fail to allocate an entry

Rather than trying to soldier on with a partially allocated cache just
throw the cache away and pretend we don't have one in case we can get a
full cache next time around.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c
index e8d15db..9099cd3 100644
--- a/drivers/base/regmap/regmap-debugfs.c
+++ b/drivers/base/regmap/regmap-debugfs.c
@@ -56,6 +56,19 @@
 	.llseek = default_llseek,
 };
 
+static void regmap_debugfs_free_dump_cache(struct regmap *map)
+{
+	struct regmap_debugfs_off_cache *c;
+
+	while (!list_empty(&map->debugfs_off_cache)) {
+		c = list_first_entry(&map->debugfs_off_cache,
+				     struct regmap_debugfs_off_cache,
+				     list);
+		list_del(&c->list);
+		kfree(c);
+	}
+}
+
 /*
  * Work out where the start offset maps into register numbers, bearing
  * in mind that we suppress hidden registers.
@@ -91,8 +104,10 @@
 			/* No cache entry?  Start a new one */
 			if (!c) {
 				c = kzalloc(sizeof(*c), GFP_KERNEL);
-				if (!c)
-					break;
+				if (!c) {
+					regmap_debugfs_free_dump_cache(map);
+					return base;
+				}
 				c->min = p;
 				c->base_reg = i;
 			}
@@ -388,16 +403,8 @@
 
 void regmap_debugfs_exit(struct regmap *map)
 {
-	struct regmap_debugfs_off_cache *c;
-
 	debugfs_remove_recursive(map->debugfs);
-	while (!list_empty(&map->debugfs_off_cache)) {
-		c = list_first_entry(&map->debugfs_off_cache,
-				     struct regmap_debugfs_off_cache,
-				     list);
-		list_del(&c->list);
-		kfree(c);
-	}
+	regmap_debugfs_free_dump_cache(map);
 	kfree(map->debugfs_name);
 }