diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 0d185ec018a5..fe3e38dd5324 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -243,6 +243,16 @@ static void regmap_format_7_9_write(struct regmap *map,
 	*out = cpu_to_be16((reg << 9) | val);
 }
 
+static void regmap_format_7_17_write(struct regmap *map,
+				    unsigned int reg, unsigned int val)
+{
+	u8 *out = map->work_buf;
+
+	out[2] = val;
+	out[1] = val >> 8;
+	out[0] = (val >> 16) | (reg << 1);
+}
+
 static void regmap_format_10_14_write(struct regmap *map,
 				    unsigned int reg, unsigned int val)
 {
@@ -885,6 +895,9 @@ struct regmap *__regmap_init(struct device *dev,
 		case 9:
 			map->format.format_write = regmap_format_7_9_write;
 			break;
+		case 17:
+			map->format.format_write = regmap_format_7_17_write;
+			break;
 		default:
 			goto err_hwlock;
 		}