[PATCH v2] imx6: Re-add mmc aliases

[Peter Robinson]

On Thu, Dec 8, 2022 at 3:23 PM Detlev Casanova
<detlev.casanova at collabora.com> wrote:
>
> In commit d0399a46e7cda63c07e3eb8558bef84cfb068028, the device tree was
> synchronized from linux and the aliases were dropped.

Is there a reason not to get this change upstreamed in to Linux and
then this wouldn't be a problem moving forward?

> They need to be kept so that the mmc cards are in the right order.
> Without the aliases, u-boot reports:
> MMC:   FSL_SDHC: 2, FSL_SDHC: 3
>
> With the aliases, u-boot reports:
> MMC:   FSL_SDHC: 0, FSL_SDHC: 1
>
> The upstream linux device tree does not contain the same aliases than
> u-boot (It keeps the devices order with /dev/mmcblk2 and /dev/mmcblk3).
> Because this board has been using different aliases in u-boot
> and linux, a imx6q-sabrelite-u-boot.dtsi file is added to be
> automatically included in imx6q-sabrelite.dts.
>
> This way, linux and u-boot each keep their own aliases and there
> is no breakage on current installations.
>
> This should never be done for new boards as we want to keep linux and
> u-boot with the same aliases as much as possible.
> This patch is only necessary to avoid breaking existing setups.
>
> Signed-off-by: Detlev Casanova <detlev.casanova at collabora.com>
>
> Gbp-Pq: Topic apertis/imx6
> Gbp-Pq: Name 0010-imx6-Re-add-mmc-aliases.patch
> ---
>  arch/arm/dts/imx6q-sabrelite-u-boot.dtsi | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
>  create mode 100644 arch/arm/dts/imx6q-sabrelite-u-boot.dtsi
>
> diff --git a/arch/arm/dts/imx6q-sabrelite-u-boot.dtsi b/arch/arm/dts/imx6q-sabrelite-u-boot.dtsi
> new file mode 100644
> index 0000000000..706ec9ba25
> --- /dev/null
> +++ b/arch/arm/dts/imx6q-sabrelite-u-boot.dtsi
> @@ -0,0 +1,15 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2022 Collabora
> + */
> +
> +#include "imx6qdl-u-boot.dtsi"
> +
> +/ {
> +       aliases {
> +               mmc0 = &usdhc3;
> +               mmc1 = &usdhc4;
> +               pwm_lcd = &pwm1;
> +               pwm_lvds = &pwm4;
> +       };
> +};
> --
> 2.38.1
>