diff options
Diffstat (limited to 'drivers/mtd/spi-nor/spi-nor.c')
| -rw-r--r-- | drivers/mtd/spi-nor/spi-nor.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index 9363f299e4ee..494b7a269872 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -284,6 +284,20 @@ static inline int set_4byte(struct spi_nor *nor, const struct flash_info *info, if (need_wren) write_disable(nor); + if (!status && !enable && + JEDEC_MFR(info) == SNOR_MFR_WINBOND) { + /* + * On Winbond W25Q256FV, leaving 4byte mode causes + * the Extended Address Register to be set to 1, so all + * 3-byte-address reads come from the second 16M. + * We must clear the register to enable normal behavior. + */ + write_enable(nor); + nor->cmd_buf[0] = 0; + nor->write_reg(nor, SPINOR_OP_WREAR, nor->cmd_buf, 1); + write_disable(nor); + } + return status; default: /* Spansion style */ |