From: Chen-Tsung Hsieh chentsung@chromium.org
[ Upstream commit 70dd83d737d8900b2d98db6dc6b928c596334d37 ]
Read back Status Register 1 to ensure that the written byte match the received value and return -EIO if read back test failed.
Without this patch, spi_nor_write_16bit_sr_and_check() only check the second half of the 16bit. It causes errors like spi_nor_sr_unlock() return success incorrectly when spi_nor_write_16bit_sr_and_check() doesn't write SR successfully.
Fixes: 39d1e3340c73 ("mtd: spi-nor: Fix clearing of QE bit on lock()/unlock()") Signed-off-by: Chen-Tsung Hsieh chentsung@chromium.org Signed-off-by: Pratyush Yadav p.yadav@ti.com Reviewed-by: Michael Walle michael@walle.cc Reviewed-by: Tudor Ambarus tudor.ambarus@microchip.com Acked-by: Pratyush Yadav p.yadav@ti.com Link: https://lore.kernel.org/r/20220126073227.3401275-1-chentsung@chromium.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mtd/spi-nor/core.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c index cc08bd707378..90f39aabc1ff 100644 --- a/drivers/mtd/spi-nor/core.c +++ b/drivers/mtd/spi-nor/core.c @@ -1007,6 +1007,15 @@ static int spi_nor_write_16bit_sr_and_check(struct spi_nor *nor, u8 sr1) if (ret) return ret;
+ ret = spi_nor_read_sr(nor, sr_cr); + if (ret) + return ret; + + if (sr1 != sr_cr[0]) { + dev_dbg(nor->dev, "SR: Read back test failed\n"); + return -EIO; + } + if (nor->flags & SNOR_F_NO_READ_CR) return 0;