[RFC PATCH 0/2] Add support to Disable the flash quad mode

[Yicong Yang <yangyicong@xxxxxxxxxxxxx>]

Previously we didn't disable the flash's quad mode when it's removed
Then comes the problem that if we next time load the flash
in SPI/Dual mode, it will not be correctly enabled as the quad enable
bits has not been cleared. I validated the condition on Cypress s25fs128s1.

This series adds the capability to disable the flash's quad mode. And
restore the flash when it's removed in spi_nor_restore().

RFC:
- I cleared quad mode bit in spi_nor_restore() when flash removed or
shutdown, follow what reset 4byte address does. But I don't know if
there is a situation that the flash is in quad mode by default, then
we should disable it in probe stage.
- The issue occurs when the user switch the spi mode of the flash.
Not sure whether a situation exists.

Yicong Yang (2):
  mtd: spi-nor: Add capability to disable flash quad mode
  mtd: spi-nor: Disable the flash quad mode in spi_nor_restore()

 drivers/mtd/spi-nor/core.c | 43 +++++++++++++++++++++++++++++++++----------
 drivers/mtd/spi-nor/core.h |  8 ++++----
 2 files changed, 37 insertions(+), 14 deletions(-)

--
2.8.1


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