diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index eefdf25..fc03171 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -2229,7 +2229,8 @@
 		 * The CSD capacity field is in units of read_blkbits.
 		 * set_capacity takes units of 512 bytes.
 		 */
-		size = card->csd.capacity << (card->csd.read_blkbits - 9);
+		size = (typeof(sector_t))card->csd.capacity
+			<< (card->csd.read_blkbits - 9);
 	}
 
 	return mmc_blk_alloc_req(card, &card->dev, size, false, NULL,