regmap: Add support for 10/14 register formating

This patch adds support for 10 bits register, 14 bits value type register
formating. This is for example used by the Analog Devices AD5380.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/base/regmap/regmap.c

@@ -90,6 +90,16 @@ static void regmap_format_7_9_write(struct regmap *map,
 	*out = cpu_to_be16((reg << 9) | val);
 }
 
+static void regmap_format_10_14_write(struct regmap *map,
+				    unsigned int reg, unsigned int val)
+{
+	u8 *out = map->work_buf;
+
+	out[2] = val;
+	out[1] = (val >> 8) | (reg << 6);
+	out[0] = reg >> 2;
+}
+
 static void regmap_format_8(void *buf, unsigned int val)
 {
 	u8 *b = buf;
@@ -188,6 +198,16 @@ struct regmap *regmap_init(struct device *dev,
 		}
 		break;
 
+	case 10:
+		switch (config->val_bits) {
+		case 14:
+			map->format.format_write = regmap_format_10_14_write;
+			break;
+		default:
+			goto err_map;
+		}
+		break;
+
 	case 8:
 		map->format.format_reg = regmap_format_8;
 		break;