diff --git a/drivers/hid/hid-picolcd_core.c b/drivers/hid/hid-picolcd_core.c
index b48092d0e139..acbb021065ec 100644
--- a/drivers/hid/hid-picolcd_core.c
+++ b/drivers/hid/hid-picolcd_core.c
@@ -290,7 +290,7 @@ static ssize_t picolcd_operation_mode_store(struct device *dev,
 		buf += 10;
 		cnt -= 10;
 	}
-	if (!report)
+	if (!report || report->maxfield != 1)
 		return -EINVAL;
 
 	while (cnt > 0 && (buf[cnt-1] == '\n' || buf[cnt-1] == '\r'))