[PATCH] ARM: dts: Add mask-tpm-reset to the device tree
Tomasz Figa
t.figa at samsung.com
Thu Jun 26 02:52:27 PDT 2014
Hi Vikas, Doug,
On 26.06.2014 11:15, Vikas Sajjan wrote:
> From: Doug Anderson <dianders at chromium.org>
>
> The mask-tpm-reset GPIO is used by the kernel to prevent the TPM from
> being reset across sleep/wake. If we don't set it to anything then
> the TPM will be reset. U-Boot will detect this as invalid
> and will reset the system on resume time. This GPIO can always be low
> and not hurt anything. It will get pulled back high again during a
> normal warm reset when it will default back to an input.
>
> To properly preserve the TPM state across suspend/resume and to make
> the chrome U-Boot happy, properly set the GPIO to mask the
> reset to the TPM.
>
> Signed-off-by: Doug Anderson <dianders at chromium.org>
> Signed-off-by: Vikas Sajjan <vikas.sajjan at samsung.com>
> ---
> arch/arm/boot/dts/exynos5420-peach-pit.dts | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
> diff --git a/arch/arm/boot/dts/exynos5420-peach-pit.dts b/arch/arm/boot/dts/exynos5420-peach-pit.dts
> index 7649982..8fd990a 100644
> --- a/arch/arm/boot/dts/exynos5420-peach-pit.dts
> +++ b/arch/arm/boot/dts/exynos5420-peach-pit.dts
> @@ -87,6 +87,18 @@
> pinctrl-0 = <&usb301_vbus_en>;
> enable-active-high;
> };
> +
> + /* We need GPX0_6 to be low at sleep time; just keep it low always */
> + mask_tpm_reset_regulator: mask-tpm-reset-regulator {
> + compatible = "regulator-fixed";
> + regulator-name = "mask-tpm-reset ";
> + gpio = <&gpx0 6 0>;
> + enable-active-low;
> + regulator-boot-on;
> + regulator-always-on;
> + pinctrl-names = "default";
> + pinctrl-0 = <&mask_tpm_reset>;
> + };
I don't think this pin is supposed to be a real regulator. If I'm right,
you should just add a hog for it, if you don't have a proper driver to
handle it.
> };
>
> &dp {
> @@ -210,6 +222,14 @@
>
>
> &pinctrl_0 {
> +
nit: No need for this blank line.
Best regards,
Tomasz
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