diff --git a/drivers/mtd/nand/raw/atmel/nand-controller.c b/drivers/mtd/nand/raw/atmel/nand-controller.c
index 3f494f7c7ecb..4cb478bbee4a 100644
--- a/drivers/mtd/nand/raw/atmel/nand-controller.c
+++ b/drivers/mtd/nand/raw/atmel/nand-controller.c
@@ -165,7 +165,7 @@ struct atmel_nand {
 	struct atmel_pmecc_user *pmecc;
 	struct gpio_desc *cdgpio;
 	int numcs;
-	struct atmel_nand_cs cs[];
+	struct atmel_nand_cs cs[] __counted_by(numcs);
 };
 
 static inline struct atmel_nand *to_atmel_nand(struct nand_chip *chip)