| Message ID | 20210324025534.1837405-1-swboyd@chromium.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 5f551b5ce55575b14c26933fe9b49365ea246b3d |
| Headers | show |
| Series | arm64: dts: qcom: trogdor: Add no-hpd to DSI bridge node | expand |
Hi Stephen, Thank you for the patch. On Tue, Mar 23, 2021 at 07:55:34PM -0700, Stephen Boyd 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 on trogdor boards. We didn't notice > this before because the kernel driver blindly disables hpd, but that > won't be true for much longer. > > 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> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > --- > arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > index 07c8b2c926c0..298af6d7fb4a 100644 > --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > @@ -595,6 +595,8 @@ sn65dsi86_bridge: bridge@2d { > clocks = <&rpmhcc RPMH_LN_BB_CLK3>; > clock-names = "refclk"; > > + no-hpd; > + > ports { > #address-cells = <1>; > #size-cells = <0>;
Hi, On Tue, Mar 23, 2021 at 7:55 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 on trogdor boards. We didn't notice > this before because the kernel driver blindly disables hpd, but that > won't be true for much longer. > > 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/sc7180-trogdor.dtsi | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > index 07c8b2c926c0..298af6d7fb4a 100644 > --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > @@ -595,6 +595,8 @@ sn65dsi86_bridge: bridge@2d { > clocks = <&rpmhcc RPMH_LN_BB_CLK3>; > clock-names = "refclk"; > > + no-hpd; > + Sigh. I can't believe that I added this for cheza in commit 0d1ce0d14bd7 ("arm64: dts: sdm845: Add "no-hpd" to sn65dsi86 on cheza") but forgot trogdor. Thanks. Reviewed-by: Douglas Anderson <dianders@chromium.org> NOTE: if you were feeling charitable you might consider sending a patch for "sdm850-lenovo-yoga-c630.dts" as well. I don't personally know if HPD is hooked up on that system, but presumably even if it is it's just as useless as it is on other systems where the bridge is used for eDP. If nothing else setting it preserves existing behavior. Someone (I forget who) requested that I word the bindings specifically to say that "no-hpd" was OK to specify in cases like that, since the bindings say: > Set if the HPD line on the bridge isn't hooked up to anything or is > otherwise unusable. -Doug
Quoting Doug Anderson (2021-03-24 08:32:00) > NOTE: if you were feeling charitable you might consider sending a > patch for "sdm850-lenovo-yoga-c630.dts" as well. I don't personally > know if HPD is hooked up on that system, but presumably even if it is > it's just as useless as it is on other systems where the bridge is > used for eDP. If nothing else setting it preserves existing behavior. Ok I can cook up another patch for this one too.
Hello: This patch was applied to qcom/linux.git (refs/heads/for-next): On Tue, 23 Mar 2021 19:55:34 -0700 you 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 on trogdor boards. We didn't notice > this before because the kernel driver blindly disables hpd, but that > won't be true for much longer. > > [...] Here is the summary with links: - arm64: dts: qcom: trogdor: Add no-hpd to DSI bridge node https://git.kernel.org/qcom/c/5f551b5ce555 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi index 07c8b2c926c0..298af6d7fb4a 100644 --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi @@ -595,6 +595,8 @@ sn65dsi86_bridge: bridge@2d { clocks = <&rpmhcc RPMH_LN_BB_CLK3>; 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 on trogdor boards. We didn't notice this before because the kernel driver blindly disables hpd, but that won't be true for much longer. 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/sc7180-trogdor.dtsi | 2 ++ 1 file changed, 2 insertions(+)