diff --git a/sst28sf040.c b/sst28sf040.c
index 6c22591..ab57835 100644
--- a/sst28sf040.c
+++ b/sst28sf040.c
@@ -115,7 +115,7 @@
 int erase_chip_28sf040(struct flashctx *flash, unsigned int addr,
 		       unsigned int blocklen)
 {
-	if ((addr != 0) || (blocklen != flash->chip->total_size * 1024)) {
+	if ((addr != 0) || (blocklen != flashprog_flash_getsize(flash))) {
 		msg_cerr("%s called with incorrect arguments\n",
 			__func__);
 		return -1;