[PATCH] mtd: spi-nor: Return error when nor->addr_width not match the device size

From: Liu Xiang
Date: Wed Nov 14 2018 - 08:09:21 EST


In is25lp256, the DWORD1 of JEDEC Basic Flash Parameter Header
is 0xfff920e5. So the DWORD1[18:17] Address Bytes bits are 0b00,
means that 3-Byte only addressing. But the device size is larger
than 16MB, nor->addr_width must be 4 to access the whole address.
An error should be returned when nor->addr_width not match
the device size in spi_nor_parse_sfdp().

Suggested-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx>
Signed-off-by: Liu Xiang <liu.xiang6@xxxxxxxxxx>
---
drivers/mtd/spi-nor/spi-nor.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 3eba13a..77eaf22 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -2669,6 +2669,10 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
}
params->size >>= 3; /* Convert to bytes. */

+ /*if the device exceeds 16MiB, addr_width must be 4*/
+ if ((params->size > 0x1000000) && (nor->addr_width == 3))
+ return -EINVAL;
+
/* Fast Read settings. */
for (i = 0; i < ARRAY_SIZE(sfdp_bfpt_reads); i++) {
const struct sfdp_bfpt_read *rd = &sfdp_bfpt_reads[i];
--
1.9.1