On Thu, Sep 03, 2020 at 08:34:57PM +0530, satya priya wrote:
> Add sleep state for BT uart to support the wakeup feature.
>
> Signed-off-by: satya priya <skakit@xxxxxxxxxxxxxx>
> Reviewed-by: Akash Asthana <akashast@xxxxxxxxxxxxxx>
> ---
> Changes in V2:
> - This patch adds sleep state for BT UART. Newly added in V2.
>
> Changes in V3:
> - Remove "output-high" for TX from both sleep and default states
> as it is not required. Configure pull-up for TX in sleep state.
>
> Changes in V4:
> - As per Matthias's comment, removed drive-strength for sleep state
> and fixed nit-pick.
>
> arch/arm64/boot/dts/qcom/sc7180-idp.dts | 37 +++++++++++++++++++++++++++++++++
> 1 file changed, 37 insertions(+)
>
> 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;
> + };
> +
> + 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 {
> pinconf-tx {
> pins = "gpio44";
Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
