| Message ID | 20201013010056.v2.3.Ie4d84af5a85e8dcb8f575845518fa39f324a827d@changeid (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | PWM backlight interpolation adjustments | expand |
Hi, On Tue, Oct 13, 2020 at 1:01 AM Alexandru Stan <amstan@chromium.org> wrote: > > Now that we have better interpolation for the backlight > ("backlight: pwm_bl: Fix interpolation"), we can now add the curve to > the trogdor boards, being careful to crop the low end. Just to make it clear, the patch this depends on hasn't landed yet. Presumably it will land in the v5.10 timeframe? That means that without extra coordination this patch can target v5.11. > Signed-off-by: Alexandru Stan <amstan@chromium.org> > --- > > arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > index bf875589d364..ccdabc6c4994 100644 > --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > @@ -179,6 +179,15 @@ pp3300_fp_tp: pp3300-fp-tp-regulator { > backlight: backlight { > compatible = "pwm-backlight"; > > + /* The panels don't seem to like anything below ~ 5% */ > + brightness-levels = < > + 196 256 324 400 484 576 676 784 900 1024 1156 1296 > + 1444 1600 1764 1936 2116 2304 2500 2704 2916 3136 > + 3364 3600 3844 4096 > + >; > + num-interpolated-steps = <64>; > + default-brightness-level = <951>; I haven't done lots of digging here, but this matches what Alexandru and Matthias agreed upon for the downstream tree and seems sane. Thus: Reviewed-by: Douglas Anderson <dianders@chromium.org>
On Tue, Oct 13, 2020 at 09:28:38AM -0700, Doug Anderson wrote: > Hi, > > On Tue, Oct 13, 2020 at 1:01 AM Alexandru Stan <amstan@chromium.org> wrote: > > > > Now that we have better interpolation for the backlight > > ("backlight: pwm_bl: Fix interpolation"), we can now add the curve to > > the trogdor boards, being careful to crop the low end. > > Just to make it clear, the patch this depends on hasn't landed yet. > Presumably it will land in the v5.10 timeframe? That means that > without extra coordination this patch can target v5.11. You're talking about patch 1 from this set? Despite the title I view the patch as changing policy (albeit one that does also fix some annoying quantization errors at the same time) so it's not necessarily a candidate for merging outside the merge window (I've not checked with Lee but I think it likely the shutter is already down for features). Moreover I'm not clear why there a dependency here that would stop the changes landing in different trees. Daniel. > > Signed-off-by: Alexandru Stan <amstan@chromium.org> > > --- > > > > arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi | 9 +++++++++ > > 1 file changed, 9 insertions(+) > > > > diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > > index bf875589d364..ccdabc6c4994 100644 > > --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > > +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > > @@ -179,6 +179,15 @@ pp3300_fp_tp: pp3300-fp-tp-regulator { > > backlight: backlight { > > compatible = "pwm-backlight"; > > > > + /* The panels don't seem to like anything below ~ 5% */ > > + brightness-levels = < > > + 196 256 324 400 484 576 676 784 900 1024 1156 1296 > > + 1444 1600 1764 1936 2116 2304 2500 2704 2916 3136 > > + 3364 3600 3844 4096 > > + >; > > + num-interpolated-steps = <64>; > > + default-brightness-level = <951>; > > I haven't done lots of digging here, but this matches what Alexandru > and Matthias agreed upon for the downstream tree and seems sane. > Thus: > > Reviewed-by: Douglas Anderson <dianders@chromium.org>
Hi, On Wed, Oct 14, 2020 at 4:33 AM Daniel Thompson <daniel.thompson@linaro.org> wrote: > > On Tue, Oct 13, 2020 at 09:28:38AM -0700, Doug Anderson wrote: > > Hi, > > > > On Tue, Oct 13, 2020 at 1:01 AM Alexandru Stan <amstan@chromium.org> wrote: > > > > > > Now that we have better interpolation for the backlight > > > ("backlight: pwm_bl: Fix interpolation"), we can now add the curve to > > > the trogdor boards, being careful to crop the low end. > > > > Just to make it clear, the patch this depends on hasn't landed yet. > > Presumably it will land in the v5.10 timeframe? That means that > > without extra coordination this patch can target v5.11. > > You're talking about patch 1 from this set? Despite the title I view > the patch as changing policy (albeit one that does also fix some annoying > quantization errors at the same time) so it's not necessarily a > candidate for merging outside the merge window (I've not checked with > Lee but I think it likely the shutter is already down for features). Ugh, I'm off by one. :( Right. New features prepared for v5.10 should already have been baking in linuxnext and merge requests have already started flowing towards Linus. After v5.10-rc1 then it'd just fixes and this doesn't really qualify. So the timing dictates that patch #1 will land in v5.11, not v5.10. > Moreover I'm not clear why there a dependency here that would stop the > changes landing in different trees. I haven't tried Alexandru's device tree patch without the associated code changes, but I guess I just assumed that it would make a really ugly (non)ideal backlight curve and we'd be better off with what we currently have (AKA no curve specified at all). Hrm, thinking about it, I guess the worst case is a slightly non-ideal backlight curve and it would be all good in the final v5.11 which would have the device tree and code changes, so you're right that both the code and device tree could target v5.11 without anything too bad... > Daniel. > > > > > Signed-off-by: Alexandru Stan <amstan@chromium.org> > > > --- > > > > > > arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi | 9 +++++++++ > > > 1 file changed, 9 insertions(+) > > > > > > diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > > > index bf875589d364..ccdabc6c4994 100644 > > > --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > > > +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > > > @@ -179,6 +179,15 @@ pp3300_fp_tp: pp3300-fp-tp-regulator { > > > backlight: backlight { > > > compatible = "pwm-backlight"; > > > > > > + /* The panels don't seem to like anything below ~ 5% */ > > > + brightness-levels = < > > > + 196 256 324 400 484 576 676 784 900 1024 1156 1296 > > > + 1444 1600 1764 1936 2116 2304 2500 2704 2916 3136 > > > + 3364 3600 3844 4096 > > > + >; > > > + num-interpolated-steps = <64>; > > > + default-brightness-level = <951>; > > > > I haven't done lots of digging here, but this matches what Alexandru > > and Matthias agreed upon for the downstream tree and seems sane. > > Thus: > > > > Reviewed-by: Douglas Anderson <dianders@chromium.org>
On Wed, Oct 14, 2020 at 06:51:19AM -0700, Doug Anderson wrote: > Hi, > > On Wed, Oct 14, 2020 at 4:33 AM Daniel Thompson > <daniel.thompson@linaro.org> wrote: > > > > On Tue, Oct 13, 2020 at 09:28:38AM -0700, Doug Anderson wrote: > > > Hi, > > > > > > On Tue, Oct 13, 2020 at 1:01 AM Alexandru Stan <amstan@chromium.org> wrote: > > > > > > > > Now that we have better interpolation for the backlight > > > > ("backlight: pwm_bl: Fix interpolation"), we can now add the curve to > > > > the trogdor boards, being careful to crop the low end. > > > > > > Just to make it clear, the patch this depends on hasn't landed yet. > > > Presumably it will land in the v5.10 timeframe? That means that > > > without extra coordination this patch can target v5.11. > > > > You're talking about patch 1 from this set? Despite the title I view > > the patch as changing policy (albeit one that does also fix some annoying > > quantization errors at the same time) so it's not necessarily a > > candidate for merging outside the merge window (I've not checked with > > Lee but I think it likely the shutter is already down for features). > > Ugh, I'm off by one. :( Right. New features prepared for v5.10 > should already have been baking in linuxnext and merge requests have > already started flowing towards Linus. After v5.10-rc1 then it'd just > fixes and this doesn't really qualify. So the timing dictates that > patch #1 will land in v5.11, not v5.10. > > > > Moreover I'm not clear why there a dependency here that would stop the > > changes landing in different trees. > > I haven't tried Alexandru's device tree patch without the associated > code changes, but I guess I just assumed that it would make a really > ugly (non)ideal backlight curve and we'd be better off with what we > currently have (AKA no curve specified at all). > > Hrm, thinking about it, I guess the worst case is a slightly non-ideal > backlight curve and it would be all good in the final v5.11 which > would have the device tree and code changes, so you're right that both > the code and device tree could target v5.11 without anything too > bad... Excellent. I'll try to remember this for v3 so I can get my Acked-by versus Reviewed-by tags correct ;-) . Daniel. > > > > Daniel. > > > > > > > > Signed-off-by: Alexandru Stan <amstan@chromium.org> > > > > --- > > > > > > > > arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi | 9 +++++++++ > > > > 1 file changed, 9 insertions(+) > > > > > > > > diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > > > > index bf875589d364..ccdabc6c4994 100644 > > > > --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > > > > +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi > > > > @@ -179,6 +179,15 @@ pp3300_fp_tp: pp3300-fp-tp-regulator { > > > > backlight: backlight { > > > > compatible = "pwm-backlight"; > > > > > > > > + /* The panels don't seem to like anything below ~ 5% */ > > > > + brightness-levels = < > > > > + 196 256 324 400 484 576 676 784 900 1024 1156 1296 > > > > + 1444 1600 1764 1936 2116 2304 2500 2704 2916 3136 > > > > + 3364 3600 3844 4096 > > > > + >; > > > > + num-interpolated-steps = <64>; > > > > + default-brightness-level = <951>; > > > > > > I haven't done lots of digging here, but this matches what Alexandru > > > and Matthias agreed upon for the downstream tree and seems sane. > > > Thus: > > > > > > Reviewed-by: Douglas Anderson <dianders@chromium.org>
diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi index bf875589d364..ccdabc6c4994 100644 --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi @@ -179,6 +179,15 @@ pp3300_fp_tp: pp3300-fp-tp-regulator { backlight: backlight { compatible = "pwm-backlight"; + /* The panels don't seem to like anything below ~ 5% */ + brightness-levels = < + 196 256 324 400 484 576 676 784 900 1024 1156 1296 + 1444 1600 1764 1936 2116 2304 2500 2704 2916 3136 + 3364 3600 3844 4096 + >; + num-interpolated-steps = <64>; + default-brightness-level = <951>; + pwms = <&cros_ec_pwm 1>; enable-gpios = <&tlmm 12 GPIO_ACTIVE_HIGH>; power-supply = <&ppvar_sys>;
Now that we have better interpolation for the backlight ("backlight: pwm_bl: Fix interpolation"), we can now add the curve to the trogdor boards, being careful to crop the low end. Signed-off-by: Alexandru Stan <amstan@chromium.org> --- arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi | 9 +++++++++ 1 file changed, 9 insertions(+)