regmap: Add provisions to have user-defined write operation

This commit is a preparatory commit to provide "no-bus" configuration
option for regmap API. It adds necessary plumbing needed to have the
ability to provide user define register write function.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/base/regmap/internal.h

@@ -75,6 +75,7 @@ struct regmap {
 	const struct regmap_access_table *precious_table;
 
 	int (*reg_read)(void *context, unsigned int reg, unsigned int *val);
+	int (*reg_write)(void *context, unsigned int reg, unsigned int val);
 
 	u8 read_flag_mask;
 	u8 write_flag_mask;

drivers/base/regmap/regmap.c

@@ -36,6 +36,10 @@ static int _regmap_update_bits(struct regmap *map, unsigned int reg,
 
 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_raw_write(void *context, unsigned int reg,
+				 unsigned int val);
 
 bool regmap_reg_in_ranges(unsigned int reg,
 			  const struct regmap_range *ranges,
@@ -580,6 +584,11 @@ struct regmap *regmap_init(struct device *dev,
 		goto err_map;
 	}
 
+	if (map->format.format_write)
+		map->reg_write = _regmap_bus_formatted_write;
+	else if (map->format.format_val)
+		map->reg_write = _regmap_bus_raw_write;
+
 	map->range_tree = RB_ROOT;
 	for (i = 0; i < config->num_ranges; i++) {
 		const struct regmap_range_cfg *range_cfg = &config->ranges[i];
@@ -986,12 +995,54 @@ static int _regmap_raw_write(struct regmap *map, unsigned int reg,
 	return ret;
 }
 
+static int _regmap_bus_formatted_write(void *context, unsigned int reg,
+				       unsigned int val)
+{
+	int ret;
+	struct regmap_range_node *range;
+	struct regmap *map = context;
+
+	BUG_ON(!map->format.format_write);
+
+	range = _regmap_range_lookup(map, reg);
+	if (range) {
+		ret = _regmap_select_page(map, &reg, range, 1);
+		if (ret != 0)
+			return ret;
+	}
+
+	map->format.format_write(map, reg, val);
+
+	trace_regmap_hw_write_start(map->dev, reg, 1);
+
+	ret = map->bus->write(map->bus_context, map->work_buf,
+			      map->format.buf_size);
+
+	trace_regmap_hw_write_done(map->dev, reg, 1);
+
+	return ret;
+}
+
+static int _regmap_bus_raw_write(void *context, unsigned int reg,
+				 unsigned int val)
+{
+	struct regmap *map = context;
+
+	BUG_ON(!map->format.format_val);
+
+	map->format.format_val(map->work_buf + map->format.reg_bytes
+			       + map->format.pad_bytes, val, 0);
+	return _regmap_raw_write(map, reg,
+				 map->work_buf +
+				 map->format.reg_bytes +
+				 map->format.pad_bytes,
+				 map->format.val_bytes);
+}
+
 int _regmap_write(struct regmap *map, unsigned int reg,
 		  unsigned int val)
 {
-	struct regmap_range_node *range;
 	int ret;
-	BUG_ON(!map->format.format_write && !map->format.format_val);
 
 	if (!map->cache_bypass && map->format.format_write) {
 		ret = regcache_write(map, reg, val);
@@ -1010,33 +1061,7 @@ int _regmap_write(struct regmap *map, unsigned int reg,
 
 	trace_regmap_reg_write(map->dev, reg, val);
 
-	if (map->format.format_write) {
-		range = _regmap_range_lookup(map, reg);
-		if (range) {
-			ret = _regmap_select_page(map, &reg, range, 1);
-			if (ret != 0)
-				return ret;
-		}
-
-		map->format.format_write(map, reg, val);
-
-		trace_regmap_hw_write_start(map->dev, reg, 1);
-
-		ret = map->bus->write(map->bus_context, map->work_buf,
-				      map->format.buf_size);
-
-		trace_regmap_hw_write_done(map->dev, reg, 1);
-
-		return ret;
-	} else {
-		map->format.format_val(map->work_buf + map->format.reg_bytes
-				       + map->format.pad_bytes, val, 0);
-		return _regmap_raw_write(map, reg,
-					 map->work_buf +
-					 map->format.reg_bytes +
-					 map->format.pad_bytes,
-					 map->format.val_bytes);
-	}
+	return map->reg_write(map, reg, val);
 }
 
 /**