[PATCH linux dev-4.10 05/10] aspeed: zaius: Disable GPIO bias via devicetree pinconf requests

[Xo Wang]

Hi Andrew,

On Wed, Apr 26, 2017 at 11:08 PM, Andrew Jeffery <andrew at aj.id.au> wrote:
> Given there are fixes presumably present in revisions beyond EVT1, the
> special-casing done in the board file is implemented by separate
> devicetrees.

I don't think anyone is using EVT1 boards any more. They don't boot
CPUs. However, I like this approach for plumbing board special-casing
and we'll probably have to do it for EVT/DVT differences.

>
> Signed-off-by: Andrew Jeffery <andrew at aj.id.au>
> ---
>  arch/arm/boot/dts/Makefile                      |  1 +
>  arch/arm/boot/dts/aspeed-bmc-opp-zaius-evt1.dts | 20 ++++++++++++++++++++
>  arch/arm/boot/dts/aspeed-bmc-opp-zaius.dts      | 10 ++++++++++
>  arch/arm/mach-aspeed/aspeed.c                   | 11 -----------
>  4 files changed, 31 insertions(+), 11 deletions(-)
>  create mode 100644 arch/arm/boot/dts/aspeed-bmc-opp-zaius-evt1.dts
>
> diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
> index 6127fd94591c..6102e7bd21ae 100644
> --- a/arch/arm/boot/dts/Makefile
> +++ b/arch/arm/boot/dts/Makefile
> @@ -989,6 +989,7 @@ dtb-$(CONFIG_ARCH_ASPEED) += aspeed-bmc-opp-palmetto.dtb \
>         aspeed-bmc-opp-garrison.dtb \
>         aspeed-bmc-opp-witherspoon.dtb \
>         aspeed-bmc-opp-zaius.dtb \
> +       aspeed-bmc-opp-zaius-evt1.dtb \
>         aspeed-ast2500-evb.dtb
>  endif
>
> diff --git a/arch/arm/boot/dts/aspeed-bmc-opp-zaius-evt1.dts b/arch/arm/boot/dts/aspeed-bmc-opp-zaius-evt1.dts
> new file mode 100644
> index 000000000000..21b87a5dbae3
> --- /dev/null
> +++ b/arch/arm/boot/dts/aspeed-bmc-opp-zaius-evt1.dts
> @@ -0,0 +1,20 @@
> +#include "aspeed-bmc-opp-zaius.dts"
> +
> +&pinctrl {
> +       pinctrl_gpiogab_unbiased: gpiogab_unbiased {
> +               pins = "A14", "E13", "D13", "C13", "B13", "Y21", "AA22", "U18";
> +               bias-disable;
> +       };
> +
> +       pinctrl_gpioi_unbiased: gpioi_unbiased {
> +               pins = "C22", "G18", "D19", "C20", "B22", "G19", "C18", "E20";
> +               bias-disable;
> +       };
> +};
> +
> +&gpio {
> +       pinctrl-names = "default";
> +       pinctrl-0 = <&pinctrl_gpioh_unbiased
> +                       &pinctrl_gpiogab_unbiased
> +                       &pinctrl_gpioi_unbiased>;
> +};
> diff --git a/arch/arm/boot/dts/aspeed-bmc-opp-zaius.dts b/arch/arm/boot/dts/aspeed-bmc-opp-zaius.dts
> index 73496c8d50f6..c6e58c5b4df1 100644
> --- a/arch/arm/boot/dts/aspeed-bmc-opp-zaius.dts
> +++ b/arch/arm/boot/dts/aspeed-bmc-opp-zaius.dts
> @@ -359,4 +359,14 @@
>
>  &pinctrl {
>         aspeed,external-nodes = <&gfx &lhc>;
> +
> +       pinctrl_gpioh_unbiased: gpioi_unbiased {
> +               pins = "A8", "C7", "B7", "A7", "D7", "B6", "A6", "E7";
> +               bias-disable;
> +       };
> +};
> +
> +&gpio {
> +       pinctrl-names = "default";
> +       pinctrl-0 = <&pinctrl_gpioh_unbiased>;
>  };

Looks good.

> diff --git a/arch/arm/mach-aspeed/aspeed.c b/arch/arm/mach-aspeed/aspeed.c
> index b3aba87964bf..f73a72676437 100644
> --- a/arch/arm/mach-aspeed/aspeed.c
> +++ b/arch/arm/mach-aspeed/aspeed.c
> @@ -124,17 +124,6 @@ static void __init do_zaius_setup(void)
>         reg = readl(AST_IO(AST_BASE_GPIO | 0x78));
>         board_rev = (reg >> 3) & 0x1F;
>
> -       /* EVT1 hacks */
> -       if (board_rev == 0) {
> -               /* Disable GPIO I, G/AB pulldowns due to weak driving buffers */
> -               reg = readl(AST_IO(AST_BASE_SCU | 0x8C));
> -               writel(reg | BIT(24) | BIT(22), AST_IO(AST_BASE_SCU | 0x8C));
> -       }

Please remove this code (in a separate commit if you prefer) and omit
aspeed-bmc-opp-zaius-evt1.dts.

> -
> -       /* Disable GPIO H/AC pulldowns to float 1-wire interface pins */
> -       reg = readl(AST_IO(AST_BASE_SCU | 0x8C));
> -       writel(reg | BIT(23), AST_IO(AST_BASE_SCU | 0x8C));
> -
>         /* Assert MAC2 PHY hardware reset */
>         /* Set pin low */
>         reg = readl(AST_IO(AST_BASE_GPIO | 0x00));
> --
> 2.9.3
>

thanks
xo