regmap: Provide debugfs read of register ranges

If a register range is named then provide a debugfs file showing the
contents of the range separately.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

3 files changed, 33 insertions, 0 deletions

diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index 27e66c3e7a59..ac869d28d5ba 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -121,6 +121,7 @@ int _regmap_write(struct regmap *map, unsigned int reg,
 struct regmap_range_node {
         struct rb_node node;
         const char *name;
+        struct regmap *map;
 
         unsigned int range_min;
         unsigned int range_max;
diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c
index 25b6843d6a41..f4b9dd01c981 100644
--- a/drivers/base/regmap/regmap-debugfs.c
+++ b/drivers/base/regmap/regmap-debugfs.c
@@ -183,6 +183,22 @@ static const struct file_operations regmap_map_fops = {
         .llseek = default_llseek,
 };
 
+static ssize_t regmap_range_read_file(struct file *file, char __user *user_buf,
+                                      size_t count, loff_t *ppos)
+{
+        struct regmap_range_node *range = file->private_data;
+        struct regmap *map = range->map;
+
+        return regmap_read_debugfs(map, range->range_min, range->range_max,
+                                   user_buf, count, ppos);
+}
+
+static const struct file_operations regmap_range_fops = {
+        .open = simple_open,
+        .read = regmap_range_read_file,
+        .llseek = default_llseek,
+};
+
 static ssize_t regmap_access_read_file(struct file *file,
                                        char __user *user_buf, size_t count,
                                        loff_t *ppos)
@@ -253,6 +269,9 @@ static const struct file_operations regmap_access_fops = {
 
 void regmap_debugfs_init(struct regmap *map, const char *name)
 {
+        struct rb_node *next;
+        struct regmap_range_node *range_node;
+
         if (name) {
                 map->debugfs_name = kasprintf(GFP_KERNEL, "%s-%s",
                                               dev_name(map->dev), name);
@@ -285,6 +304,18 @@ void regmap_debugfs_init(struct regmap *map, const char *name)
                 debugfs_create_bool("cache_bypass", 0400, map->debugfs,
                                     &map->cache_bypass);
         }
+
+        next = rb_first(&map->range_tree);
+        while (next) {
+                range_node = rb_entry(next, struct regmap_range_node, node);
+
+                if (range_node->name)
+                        debugfs_create_file(range_node->name, 0400,
+                                            map->debugfs, range_node,
+                                            &regmap_range_fops);
+
+                next = rb_next(&range_node->node);
+        }
 }
 
 void regmap_debugfs_exit(struct regmap *map)
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index ce5129df4406..366b629f4b10 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -579,6 +579,7 @@ struct regmap *regmap_init(struct device *dev,
                         goto err_range;
                 }
 
+                new->map = map;
                 new->name = range_cfg->name;
                 new->range_min = range_cfg->range_min;
                 new->range_max = range_cfg->range_max;