1 files changed, 26 insertions, 0 deletions

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 63e30ef096e2..2209de0ceabc 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -35,10 +35,14 @@ static int _regmap_update_bits(struct regmap *map, unsigned int reg,
                                unsigned int mask, unsigned int val,
                                bool *change);
 
+static int _regmap_bus_reg_read(void *context, unsigned int reg,
+                                unsigned int *val);
 static int _regmap_bus_read(void *context, unsigned int reg,
                             unsigned int *val);
 static int _regmap_bus_formatted_write(void *context, unsigned int reg,
                                        unsigned int val);
+static int _regmap_bus_reg_write(void *context, unsigned int reg,
+                                 unsigned int val);
 static int _regmap_bus_raw_write(void *context, unsigned int reg,
                                  unsigned int val);
 
@@ -495,6 +499,12 @@ struct regmap *regmap_init(struct device *dev,
 
                 map->defer_caching = false;
                 goto skip_format_initialization;
+        } else if (!bus->read || !bus->write) {
+                map->reg_read = _regmap_bus_reg_read;
+                map->reg_write = _regmap_bus_reg_write;
+
+                map->defer_caching = false;
+                goto skip_format_initialization;
         } else {
                 map->reg_read  = _regmap_bus_read;
         }
@@ -1284,6 +1294,14 @@ static int _regmap_bus_formatted_write(void *context, unsigned int reg,
         return ret;
 }
 
+static int _regmap_bus_reg_write(void *context, unsigned int reg,
+                                 unsigned int val)
+{
+        struct regmap *map = context;
+
+        return map->bus->reg_write(map->bus_context, reg, val);
+}
+
 static int _regmap_bus_raw_write(void *context, unsigned int reg,
                                  unsigned int val)
 {
@@ -1925,6 +1943,14 @@ static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
         return ret;
 }
 
+static int _regmap_bus_reg_read(void *context, unsigned int reg,
+                                unsigned int *val)
+{
+        struct regmap *map = context;
+
+        return map->bus->reg_read(map->bus_context, reg, val);
+}
+
 static int _regmap_bus_read(void *context, unsigned int reg,
                             unsigned int *val)
 {