From: Chen-Tsung Hsieh <chentsung@xxxxxxxxxxxx>
[ 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@xxxxxxxxxxxx>
Signed-off-by: Pratyush Yadav <p.yadav@xxxxxx>
Reviewed-by: Michael Walle <michael@xxxxxxxx>
Reviewed-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
Acked-by: Pratyush Yadav <p.yadav@xxxxxx>
Link: https://lore.kernel.org/r/20220126073227.3401275-1-chentsung@xxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 2b26a875a855..e8146a47da12 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -827,6 +827,15 @@ 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;
--
2.35.1
