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mtd: spi-nor: Check bus width while setting QE bit

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spi_nor_write_16bit_sr_and_check() should also check if bus width is
4 before setting QE bit.

Fixes: 39d1e3340c ("mtd: spi-nor: Fix clearing of QE bit on lock()/unlock()")
Suggested-by: Michael Walle <michael@walle.cc>
Suggested-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20230818064524.1229100-2-hsinyi@chromium.org
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
This commit is contained in:
Hsin-Yi Wang 2023-08-18 14:42:23 +08:00 committed by Tudor Ambarus
parent aa517a29d6
commit f01d8155a9
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GPG key ID: 4B554F47A58D14E9
1 changed files with 10 additions and 9 deletions
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19
drivers/mtd/spi-nor/core.c
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@ -870,21 +870,22 @@ static int spi_nor_write_16bit_sr_and_check(struct spi_nor *nor, u8 sr1)
ret = spi_nor_read_cr(nor, &sr_cr[1]);
if (ret)
return ret;
} else if (nor->params->quad_enable) {
} else if (spi_nor_get_protocol_width(nor->read_proto) == 4 &&
spi_nor_get_protocol_width(nor->write_proto) == 4 &&
nor->params->quad_enable) {
/*
* If the Status Register 2 Read command (35h) is not
* supported, we should at least be sure we don't
* change the value of the SR2 Quad Enable bit.
*
* We can safely assume that when the Quad Enable method is
* set, the value of the QE bit is one, as a consequence of the
* nor->params->quad_enable() call.
* When the Quad Enable method is set and the buswidth is 4, we
* can safely assume that the value of the QE bit is one, as a
* consequence of the nor->params->quad_enable() call.
*
* We can safely assume that the Quad Enable bit is present in
* the Status Register 2 at BIT(1). According to the JESD216
* revB standard, BFPT DWORDS[15], bits 22:20, the 16-bit
* Write Status (01h) command is available just for the cases
* in which the QE bit is described in SR2 at BIT(1).
* According to the JESD216 revB standard, BFPT DWORDS[15],
* bits 22:20, the 16-bit Write Status (01h) command is
* available just for the cases in which the QE bit is
* described in SR2 at BIT(1).
*/
sr_cr[1] = SR2_QUAD_EN_BIT1;
} else {