[PATCH v4 1/3] spi: nxp_fspi: new driver for the FlexSPI controller

[Jagan Teki]

On Wed, Dec 18, 2019 at 4:40 AM Michael Walle <michael at walle.cc> wrote:
>
> This is a port of the kernel's spi-nxp-fspi driver. It uses the new
> spi-mem interface and does not expose the more generic spi-xfer
> interface. The source was taken from the v5.3-rc3 tag.
>
> The port was straightforward:
>  - remove the interrupt handling and the completion by busy polling the
>    controller
>  - remove locks
>  - move the setup of the memory windows into claim_bus()
>  - move the setup of the speed into set_speed()
>  - port the device tree bindings from the original fspi_probe() to
>    ofdata_to_platdata()
>
> There were only some style change fixes, no change in any logic. For
> example, there are busy loops where the return code is not handled
> correctly, eg. only prints a warning with WARN_ON(). This port
> intentionally left most functions unchanged to ease future bugfixes.
>
> This was tested on a custom LS1028A board. Because the LS1028A doesn't
> have proper clock framework support, changing the clock speed was not
> tested. This also means that it is not possible to change the SPI
> speed on LS1028A for now (neither is it possible in the linux driver).
>
> Signed-off-by: Michael Walle <michael at walle.cc>
> Reviewed-by: Jagan Teki <jagan at amarulasolutions.com>
> Tested-by: Kuldeep Singh <kuldeep.singh at nxp.com>

Applied to u-boot-spi/master