1 files changed, 49 insertions, 0 deletions

diff --git a/drivers/base/regmap/regcache-rbtree.c b/drivers/base/regmap/regcache-rbtree.c
index e71320f61d18..7767cbb8d15a 100644
--- a/drivers/base/regmap/regcache-rbtree.c
+++ b/drivers/base/regmap/regcache-rbtree.c
@@ -11,7 +11,9 @@
  */
 
 #include <linux/slab.h>
+#include <linux/debugfs.h>
 #include <linux/rbtree.h>
+#include <linux/seq_file.h>
 
 #include "internal.h"
 
@@ -125,6 +127,51 @@ static int regcache_rbtree_insert(struct rb_root *root,
         return 1;
 }
 
+#ifdef CONFIG_DEBUG_FS
+static int rbtree_show(struct seq_file *s, void *ignored)
+{
+        struct regmap *map = s->private;
+        struct regcache_rbtree_ctx *rbtree_ctx = map->cache;
+        struct regcache_rbtree_node *n;
+        struct rb_node *node;
+        unsigned int base, top;
+        int nodes = 0;
+        int registers = 0;
+
+        mutex_lock(&map->lock);
+
+        for (node = rb_first(&rbtree_ctx->root); node != NULL;
+             node = rb_next(node)) {
+                n = container_of(node, struct regcache_rbtree_node, node);
+
+                regcache_rbtree_get_base_top_reg(n, &base, &top);
+                seq_printf(s, "%x-%x (%d)\n", base, top, top - base + 1);
+
+                nodes++;
+                registers += top - base + 1;
+        }
+
+        seq_printf(s, "%d nodes, %d registers, average %d registers\n",
+                   nodes, registers, registers / nodes);
+
+        mutex_unlock(&map->lock);
+
+        return 0;
+}
+
+static int rbtree_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, rbtree_show, inode->i_private);
+}
+
+static const struct file_operations rbtree_fops = {
+        .open           = rbtree_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+};
+#endif
+
 static int regcache_rbtree_init(struct regmap *map)
 {
         struct regcache_rbtree_ctx *rbtree_ctx;
@@ -147,6 +194,8 @@ static int regcache_rbtree_init(struct regmap *map)
                         goto err;
         }
 
+        debugfs_create_file("rbtree", 0400, map->debugfs, map, &rbtree_fops);
+
         return 0;
 
 err: