[PATCH RFC 0/4] Add set_iofv() callback

[Biju Das <biju.das.jz@xxxxxxxxxxxxxx>]

As per section 8.14 on the AT25QL128A hardware manual[1],
IO0..IO3 must be set to Hi-Z state for this flash for fast read quad IO.
Snippet from HW manual section 8.14:
The upper nibble of the Mode(M7-4) controls the length of the next FAST
Read Quad IO instruction through the inclusion or exclusion of the first
byte instruction code. The lower nibble bits of the Mode(M3-0) are don't
care. However, the IO pins must be high-impedance before the falling edge
of the first data out clock.

Add set_iofv() callback for configuring IO fixed values to control the
pin state.

[1]
https://www.renesas.com/eu/en/document/dst/at25ql128a-datasheet?r=1608586

Ref:
 https://patchwork.kernel.org/project/linux-renesas-soc/patch/20230830145835.296690-1-biju.das.jz@xxxxxxxxxxxxxx/

Biju Das (4):
  spi: spi-mem: Add set_iofv() callback
  mtd: spi-nor: Add post_sfdp() callback
  memory: renesas-rpc-if: Add support for overriding IO fixed values
  spi: rpc-if: Add set_iofv() callback

 drivers/memory/renesas-rpc-if.c | 20 ++++++++++++++++++++
 drivers/mtd/spi-nor/core.c      | 20 ++++++++++++++++++++
 drivers/spi/spi-mem.c           | 20 ++++++++++++++++++++
 drivers/spi/spi-rpc-if.c        |  9 +++++++++
 include/linux/spi/spi-mem.h     |  4 ++++
 include/memory/renesas-rpc-if.h |  1 +
 6 files changed, 74 insertions(+)

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2.25.1