mtd: nand: silence some shift wrap warnings

There are static checkers which complain when we declare variables as
64 bit bitfields but only use the lower 32 bits because of shift
wrapping.  In this case "len" is declared as u64 as opposed to unsigned
long or something which might be 32 bits.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 8f04fb0..761ef2f 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -108,13 +108,13 @@
 	int ret = 0;
 
 	/* Start address must align on block boundary */
-	if (ofs & ((1 << chip->phys_erase_shift) - 1)) {
+	if (ofs & ((1ULL << chip->phys_erase_shift) - 1)) {
 		pr_debug("%s: unaligned address\n", __func__);
 		ret = -EINVAL;
 	}
 
 	/* Length must align on block boundary */
-	if (len & ((1 << chip->phys_erase_shift) - 1)) {
+	if (len & ((1ULL << chip->phys_erase_shift) - 1)) {
 		pr_debug("%s: length not block aligned\n", __func__);
 		ret = -EINVAL;
 	}
@@ -394,7 +394,7 @@
 		memset(&einfo, 0, sizeof(einfo));
 		einfo.mtd = mtd;
 		einfo.addr = ofs;
-		einfo.len = 1 << chip->phys_erase_shift;
+		einfo.len = 1ULL << chip->phys_erase_shift;
 		nand_erase_nand(mtd, &einfo, 0);
 
 		/* Write bad block marker to OOB */
@@ -2630,7 +2630,7 @@
 		}
 
 		/* Increment page address and decrement length */
-		len -= (1 << chip->phys_erase_shift);
+		len -= (1ULL << chip->phys_erase_shift);
 		page += pages_per_block;
 
 		/* Check, if we cross a chip boundary */