| Message ID | 20210324191549.2043808-1-swboyd@chromium.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | arm64: dts: qcom: c630: Add no-hpd to DSI bridge node | expand |
Hi, On Wed, Mar 24, 2021 at 12:15 PM Stephen Boyd <swboyd@chromium.org> wrote: > > We should indicate that we're not using the HPD pin on this device, per > the binding document. Otherwise if code in the future wants to enable > HPD in the bridge when this property is absent we'll be wasting power > powering hpd when we don't use it. It's not really about wasting power. It's really more about: a) If HPD is actually hooked up on the board, it's actually _slower_ to use it than to just assume the worst case time. b) If HPD isn't hooked up but we try to use it then everything will just fail. I don't know which of a) or b) is true, but I'd imagine that one or the other is. > Presumably this board isn't using hpd > on the bridge. > > Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> > Cc: Douglas Anderson <dianders@chromium.org> Cc: Steev Klimaszewski <steev@kali.org> > Fixes: 7ec3e67307f8 ("arm64: dts: qcom: sc7180-trogdor: add initial trogdor and lazor dt") Wrong Fixes? > Signed-off-by: Stephen Boyd <swboyd@chromium.org> > --- > arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts b/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts > index 140db2d5ba31..c2a709a384e9 100644 > --- a/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts > +++ b/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts > @@ -376,6 +376,8 @@ sn65dsi86: bridge@2c { > clocks = <&sn65dsi86_refclk>; > clock-names = "refclk"; > > + no-hpd; > + > ports { > #address-cells = <1>; > #size-cells = <0>; > > base-commit: a38fd8748464831584a19438cbb3082b5a2dab15 > -- > https://chromeos.dev >
diff --git a/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts b/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts index 140db2d5ba31..c2a709a384e9 100644 --- a/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts +++ b/arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts @@ -376,6 +376,8 @@ sn65dsi86: bridge@2c { clocks = <&sn65dsi86_refclk>; clock-names = "refclk"; + no-hpd; + ports { #address-cells = <1>; #size-cells = <0>;
We should indicate that we're not using the HPD pin on this device, per the binding document. Otherwise if code in the future wants to enable HPD in the bridge when this property is absent we'll be wasting power powering hpd when we don't use it. Presumably this board isn't using hpd on the bridge. Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Cc: Douglas Anderson <dianders@chromium.org> Fixes: 7ec3e67307f8 ("arm64: dts: qcom: sc7180-trogdor: add initial trogdor and lazor dt") Signed-off-by: Stephen Boyd <swboyd@chromium.org> --- arch/arm64/boot/dts/qcom/sdm850-lenovo-yoga-c630.dts | 2 ++ 1 file changed, 2 insertions(+) base-commit: a38fd8748464831584a19438cbb3082b5a2dab15