[PATCH v2 2/2] mtd: spi-nor: Disable the flash quad mode in spi_nor_restore()

Yicong Yang yangyicong at hisilicon.com
Mon Jul 6 05:22:36 EDT 2020

If the flash's quad mode is enabled, it'll remain in the quad mode when
it's removed. If we drive the flash next time in Standard/Dual SPI mode,
the QE bit is not cleared and the function of flash's WP# and RESET#/HOLD#
have been switched to IO2 and IO3 and are not restored.

Disable the Quad mode in spi_nor_restore(), then the flash's QE bit will
be cleared when removed. This will make sure the flash always enter the
Standard/Dual SPI mode when loaded.

Signed-off-by: Yicong Yang <yangyicong at hisilicon.com>
Reviewed-by: Pratyush Yadav <p.yadav at ti.com>
 drivers/mtd/spi-nor/core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index f3d4b96..2099403 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -3000,6 +3000,8 @@ void spi_nor_restore(struct spi_nor *nor)
 	if (nor->addr_width == 4 && !(nor->flags & SNOR_F_4B_OPCODES) &&
 	    nor->flags & SNOR_F_BROKEN_RESET)
 		nor->params->set_4byte_addr_mode(nor, false);
+	spi_nor_quad_enable(nor, false);

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