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>

drivers/mtd/nand/nand_base.c

@@ -108,13 +108,13 @@ static int check_offs_len(struct mtd_info *mtd,
 	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 @@ static int nand_block_markbad_lowlevel(struct mtd_info *mtd, loff_t ofs)
 		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 @@ int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
 		}
 
 		/* 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 */