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SubjectRe: [PATCH V4 2/4] arm64: dts: qcom: sc7180: Improve the pin config settings for CTS and TX
Hi Doug,

On 2020-09-10 02:58, Doug Anderson wrote:
> Hi,
>
> On Thu, Sep 3, 2020 at 8:07 AM satya priya <skakit@codeaurora.org>
> wrote:
>>
>> --- a/arch/arm64/boot/dts/qcom/sc7180-idp.dts
>> +++ b/arch/arm64/boot/dts/qcom/sc7180-idp.dts
>> @@ -474,32 +474,30 @@
>> &qup_uart3_default {
>> pinconf-cts {
>> /*
>> - * Configure a pull-down on 38 (CTS) to match the pull
>> of
>> - * the Bluetooth module.
>> + * 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-pull-down;
>> - output-high;
>
> Weird, how did that output-high sneak in there? Glad it's going away.
>
>
>> + bias-disable;
>
> I'm not convinced that the removal of the pul is the correct thing
> here. Specifically for the rx line the comment makes the argument
> that if we power off the Bluetooth module then it will stop driving
> this pin. In that case if we remove the pull here then the line will
> be floating and that can cause some extra power consumption as the
> line floats between different logic levels. Do you really need to
> remove this pull?
>

Okay, will keep the pull-down back for CTS.

> Same comment for the next patch where you add the sleep settings.
>
>
> -Doug

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