Re: [PATCH V4 3/4] arm64: dts: qcom: sc7180: Add sleep state for BT UART

[Doug Anderson]

Hi,

On Thu, Sep 3, 2020 at 8:08 AM satya priya <skakit@xxxxxxxxxxxxxx> wrote:
>
> diff --git a/arch/arm64/boot/dts/qcom/sc7180-idp.dts b/arch/arm64/boot/dts/qcom/sc7180-idp.dts
> index cecac3e..77e3523 100644
> --- a/arch/arm64/boot/dts/qcom/sc7180-idp.dts
> +++ b/arch/arm64/boot/dts/qcom/sc7180-idp.dts
> @@ -507,6 +507,43 @@
>         };
>  };
>
> +&qup_uart3_sleep {
> +       pinconf-cts {
> +               /*
> +                * Configure no-pull on CTS. As this is driven by BT, do not
> +                * specify any pull in order to not conflict with BT pulls.
> +                */
> +               pins = "gpio38";
> +               bias-disable;

Same comment as in the previous patch that I'm not convinced removing
the bias here is correct.


> +       };
> +
> +       pinconf-rts {
> +               /*
> +                * Configure pull-down on RTS to make sure that the BT SoC can
> +                * wake up the system by sending wakeup bytes during suspend.
> +                */
> +               pins = "gpio39";
> +               bias-pull-down;
> +       };
> +
> +       pinconf-tx {
> +               /* Configure pull-up on TX when it isn't actively driven */
> +               pins = "gpio40";
> +               bias-pull-up;
> +       };
> +
> +       pinconf-rx {
> +               /*
> +                * Configure a pull-up on RX. This is needed to avoid
> +                * garbage data when the TX pin of the Bluetooth module is
> +                * in tri-state (module powered off or not driving the
> +                * signal yet).
> +                */
> +               pins = "gpio41";
> +               bias-pull-up;
> +       };
> +};
> +
>  &qup_uart8_default {

Slight nit that "default" starts with a "d" which sorts before "sleep"
which starts with an "s".  Thus "qup_uart8_default" should be above
"qup_uart3_sleep", not below.