Messages in this thread | | | Date | Wed, 19 Aug 2020 09:13:11 -0700 | From | Matthias Kaehlcke <> | Subject | Re: [PATCH V2 2/3] arm64: dts: qcom: sc7180: Add sleep pin ctrl for BT uart |
| |
On Wed, Aug 19, 2020 at 07:19:25PM +0530, skakit@codeaurora.org wrote: > On 2020-08-17 23:31, Matthias Kaehlcke wrote: > > On Fri, Jul 24, 2020 at 09:28:01AM +0530, satya priya wrote: > > > Add sleep pin ctrl for BT uart, and also change the bias > > > configuration to match Bluetooth module. > > > > > > Signed-off-by: satya priya <skakit@codeaurora.org> > > > --- > > > Changes in V2: > > > - This patch adds sleep state for BT UART. Newly added in V2. > > > > > > arch/arm64/boot/dts/qcom/sc7180-idp.dts | 42 > > > ++++++++++++++++++++++++++++----- > > > 1 file changed, 36 insertions(+), 6 deletions(-) > > > > > > diff --git a/arch/arm64/boot/dts/qcom/sc7180-idp.dts > > > b/arch/arm64/boot/dts/qcom/sc7180-idp.dts > > > index 26cc491..bc919f2 100644 > > > --- a/arch/arm64/boot/dts/qcom/sc7180-idp.dts > > > +++ b/arch/arm64/boot/dts/qcom/sc7180-idp.dts > > > @@ -469,20 +469,50 @@ > > > > > > &qup_uart3_default { > > > pinconf-cts { > > > - /* > > > - * Configure a pull-down on 38 (CTS) to match the pull of > > > - * the Bluetooth module. > > > - */ > > > + /* Configure no pull on 38 (CTS) to match Bluetooth module */ > > > > Has the pull from the Bluetooth module been removed or did the previous > > config > > incorrectly claim that the Bluetooth module has a pull-down? > > > > The previous config was incorrect, so we corrected it to match the pull of > BT.
The pull config of the BT controller varies depending on its state, could you clarify which state you intend to match?
> > > > pins = "gpio38"; > > > + bias-disable; > > > + }; > > > + > > > + pinconf-rts { > > > + /* We'll drive 39 (RTS), so configure pull-down */ > > > + pins = "gpio39"; > > > + drive-strength = <2>; > > > bias-pull-down; > > > + }; > > > + > > > + pinconf-tx { > > > + /* We'll drive 40 (TX), so no pull */ > > > > The rationales for RTS and TX contradict each other. According to the > > comment > > the reason to configure a pull-down on RTS is that it is driven by the > > host. > > Then for TX the reason to configure no pull is that it is driven by the > > host. > > > > Please make sure the comments *really* describe the rationale, otherwise > > they > > are just confusing. > > The rationale for RTS is that we don't want it to be floating and want to > make sure that it is pulled down, to receive bytes. Will modify the comment > mentioning the same.
Could you clarify what you mean with "to receive bytes"?
Thanks
Matthias
| |