[PATCH] imx: imx7d-sdb: fix ethernet, sync .dts with linux

[Fabio Estevam]

Hi Rasmus,

On Thu, Sep 16, 2021 at 11:53 AM Rasmus Villemoes
<rasmus.villemoes at prevas.dk> wrote:
>
> Commit 0d52bab46 (mx7dsabre: Enable DM_ETH) changed these flags from 0
> (aka GPIO_ACTIVE_HIGH) to GPIO_ACTIVE_LOW. It claimed to "Also sync
> device tree with v5.5-rc1", but in the linux tree, these gpios have
> always been GPIO_ACTIVE_HIGH ever since this node was introduced
> around v4.13 (linux commit 184f39b5).
>
> I'm guessing that the reason for the GPIO_ACTIVE_LOW was to work
> around the behaviour of the soft-spi driver back then, which
> effectively defaulted to spi-mode 3 and not 0. That was arguably a bug
> in the soft-spi driver, which then got fixed in 0e146993bb3 (spi: add
> support for all spi modes with soft spi), but that commit then broke
> ethernet on this board.
>
> Fix it by setting the gpios as active high, which as a bonus actually
> brings us in sync with the .dts in the linux source tree.
>
> Without this, one gets
>
>     Net:   Could not get PHY for FEC0: addr 0
>     No ethernet found.
>
> With this, ethernet (at least ping and tftp) works as expected from
> the U-Boot shell.
>
> Cc: Fabio Estevam <festevam at gmail.com>
> Cc: Joris Offouga <offougajoris at gmail.com>
> Cc: "Christian Bräuner Sørensen" <yocto at bsorensen.net>
> Signed-off-by: Rasmus Villemoes <rasmus.villemoes at prevas.dk>

Thanks for the fix:

Reviewed-by: Fabio Estevam <festevam at gmail.com>