diff --git a/drivers/mtd_mci/mtd_mci.c b/drivers/mtd_mci/mtd_mci.c
index 7c83260417..77da2a2230 100644
--- a/drivers/mtd_mci/mtd_mci.c
+++ b/drivers/mtd_mci/mtd_mci.c
@@ -118,10 +118,11 @@ static int mtd_mci_erase_sector(mtd_dev_t *dev, uint32_t sector, uint32_t count)
 {
     (void)dev;
 
-    while (count--) {
-        mci_ioctl(CTRL_ERASE_SECTOR, &sector);
-        ++sector;
-    }
+    uint32_t arg[2] = {
+        sector, sector + count - 1
+    };
+
+    mci_ioctl(CTRL_ERASE_SECTOR, arg);
     return 0;
 }