* [PATCH] ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel [not found] <1421749355-23050-1-git-send-email-r63905@freescale.com> @ 2015-01-20 11:38 ` Shawn Guo 2015-01-22 15:38 ` Philipp Zabel 0 siblings, 1 reply; 4+ messages in thread From: Shawn Guo @ 2015-01-20 11:38 UTC (permalink / raw) To: linux-arm-kernel Add LAKML and a few interested people. Shawn On Tue, Jan 20, 2015 at 06:22:35PM +0800, Robby Cai wrote: > Hannstar XGA panel is used by default on i.MX6QDL Sabre Auto/Lite/SD > or derived board. > > According to its data sheet [1], > a) the dimming duty cycle is 20% - 100%. > This patch changes the brightness-level from 20 to 100 with step 10 to > make it straight-forward. > b) the typical dimming frequency is 20KHz. > The previous setting is 200Hz. This patch corrects it. > > [1] > http://boundarydevices.com/wp-content/uploads/2013/06/HSD100PXN1-A00-C11-1.0.pdf > > Signed-off-by: Robby Cai <r63905@freescale.com> > --- > arch/arm/boot/dts/imx6qdl-gw52xx.dtsi | 6 +++--- > arch/arm/boot/dts/imx6qdl-gw53xx.dtsi | 6 +++--- > arch/arm/boot/dts/imx6qdl-gw54xx.dtsi | 6 +++--- > arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi | 6 +++--- > arch/arm/boot/dts/imx6qdl-sabreauto.dtsi | 6 +++--- > arch/arm/boot/dts/imx6qdl-sabrelite.dtsi | 6 +++--- > arch/arm/boot/dts/imx6qdl-sabresd.dtsi | 6 +++--- > 7 files changed, 21 insertions(+), 21 deletions(-) > > diff --git a/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi b/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi > index b5756c2..33484d8 100644 > --- a/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi > +++ b/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi > @@ -29,9 +29,9 @@ > > backlight { > compatible = "pwm-backlight"; > - pwms = <&pwm4 0 5000000>; > - brightness-levels = <0 4 8 16 32 64 128 255>; > - default-brightness-level = <7>; > + pwms = <&pwm4 0 50000>; > + brightness-levels = <0 20 30 40 50 60 70 80 90 100>; > + default-brightness-level = <9>; > }; > > leds { > diff --git a/arch/arm/boot/dts/imx6qdl-gw53xx.dtsi b/arch/arm/boot/dts/imx6qdl-gw53xx.dtsi > index 86f03c1..0d01751 100644 > --- a/arch/arm/boot/dts/imx6qdl-gw53xx.dtsi > +++ b/arch/arm/boot/dts/imx6qdl-gw53xx.dtsi > @@ -30,9 +30,9 @@ > > backlight { > compatible = "pwm-backlight"; > - pwms = <&pwm4 0 5000000>; > - brightness-levels = <0 4 8 16 32 64 128 255>; > - default-brightness-level = <7>; > + pwms = <&pwm4 0 50000>; > + brightness-levels = <0 20 30 40 50 60 70 80 90 100>; > + default-brightness-level = <9>; > }; > > leds { > diff --git a/arch/arm/boot/dts/imx6qdl-gw54xx.dtsi b/arch/arm/boot/dts/imx6qdl-gw54xx.dtsi > index 4a8d97f..8973bf2 100644 > --- a/arch/arm/boot/dts/imx6qdl-gw54xx.dtsi > +++ b/arch/arm/boot/dts/imx6qdl-gw54xx.dtsi > @@ -30,9 +30,9 @@ > > backlight { > compatible = "pwm-backlight"; > - pwms = <&pwm4 0 5000000>; > - brightness-levels = <0 4 8 16 32 64 128 255>; > - default-brightness-level = <7>; > + pwms = <&pwm4 0 50000>; > + brightness-levels = <0 20 30 40 50 60 70 80 90 100>; > + default-brightness-level = <9>; > }; > > leds { > diff --git a/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi b/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi > index 0821812..5453cf0 100644 > --- a/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi > +++ b/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi > @@ -124,9 +124,9 @@ > > backlight_lvds { > compatible = "pwm-backlight"; > - pwms = <&pwm4 0 5000000>; > - brightness-levels = <0 4 8 16 32 64 128 255>; > - default-brightness-level = <7>; > + pwms = <&pwm4 0 50000>; > + brightness-levels = <0 20 30 40 50 60 70 80 90 100>; > + default-brightness-level = <9>; > power-supply = <®_3p3v>; > status = "okay"; > }; > diff --git a/arch/arm/boot/dts/imx6qdl-sabreauto.dtsi b/arch/arm/boot/dts/imx6qdl-sabreauto.dtsi > index 009abd6..2bfcf5a 100644 > --- a/arch/arm/boot/dts/imx6qdl-sabreauto.dtsi > +++ b/arch/arm/boot/dts/imx6qdl-sabreauto.dtsi > @@ -38,9 +38,9 @@ > > backlight { > compatible = "pwm-backlight"; > - pwms = <&pwm3 0 5000000>; > - brightness-levels = <0 4 8 16 32 64 128 255>; > - default-brightness-level = <7>; > + pwms = <&pwm3 0 50000>; > + brightness-levels = <0 20 30 40 50 60 70 80 90 100>; > + default-brightness-level = <9>; > status = "okay"; > }; > }; > diff --git a/arch/arm/boot/dts/imx6qdl-sabrelite.dtsi b/arch/arm/boot/dts/imx6qdl-sabrelite.dtsi > index 0b28a9d..d1409c0 100644 > --- a/arch/arm/boot/dts/imx6qdl-sabrelite.dtsi > +++ b/arch/arm/boot/dts/imx6qdl-sabrelite.dtsi > @@ -123,9 +123,9 @@ > > backlight_lvds { > compatible = "pwm-backlight"; > - pwms = <&pwm4 0 5000000>; > - brightness-levels = <0 4 8 16 32 64 128 255>; > - default-brightness-level = <7>; > + pwms = <&pwm4 0 50000>; > + brightness-levels = <0 20 30 40 50 60 70 80 90 100>; > + default-brightness-level = <9>; > power-supply = <®_3p3v>; > status = "okay"; > }; > diff --git a/arch/arm/boot/dts/imx6qdl-sabresd.dtsi b/arch/arm/boot/dts/imx6qdl-sabresd.dtsi > index f1cd214..3efc363 100644 > --- a/arch/arm/boot/dts/imx6qdl-sabresd.dtsi > +++ b/arch/arm/boot/dts/imx6qdl-sabresd.dtsi > @@ -115,9 +115,9 @@ > > backlight { > compatible = "pwm-backlight"; > - pwms = <&pwm1 0 5000000>; > - brightness-levels = <0 4 8 16 32 64 128 255>; > - default-brightness-level = <7>; > + pwms = <&pwm1 0 50000>; > + brightness-levels = <0 20 30 40 50 60 70 80 90 100>; > + default-brightness-level = <9>; > status = "okay"; > }; > > -- > 1.9.1 > ^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH] ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel 2015-01-20 11:38 ` [PATCH] ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel Shawn Guo @ 2015-01-22 15:38 ` Philipp Zabel 2015-01-26 14:44 ` Robby.Cai at freescale.com 0 siblings, 1 reply; 4+ messages in thread From: Philipp Zabel @ 2015-01-22 15:38 UTC (permalink / raw) To: linux-arm-kernel Am Dienstag, den 20.01.2015, 19:38 +0800 schrieb Shawn Guo: > Add LAKML and a few interested people. > > Shawn > > On Tue, Jan 20, 2015 at 06:22:35PM +0800, Robby Cai wrote: > > Hannstar XGA panel is used by default on i.MX6QDL Sabre Auto/Lite/SD > > or derived board. > > > > According to its data sheet [1], > > a) the dimming duty cycle is 20% - 100%. > > This patch changes the brightness-level from 20 to 100 with step 10 to > > make it straight-forward. > > b) the typical dimming frequency is 20KHz. > > The previous setting is 200Hz. This patch corrects it. > > > > [1] > > http://boundarydevices.com/wp-content/uploads/2013/06/HSD100PXN1-A00-C11-1.0.pdf > > > > Signed-off-by: Robby Cai <r63905@freescale.com> > > --- > > arch/arm/boot/dts/imx6qdl-gw52xx.dtsi | 6 +++--- > > arch/arm/boot/dts/imx6qdl-gw53xx.dtsi | 6 +++--- > > arch/arm/boot/dts/imx6qdl-gw54xx.dtsi | 6 +++--- > > arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi | 6 +++--- > > arch/arm/boot/dts/imx6qdl-sabreauto.dtsi | 6 +++--- > > arch/arm/boot/dts/imx6qdl-sabrelite.dtsi | 6 +++--- > > arch/arm/boot/dts/imx6qdl-sabresd.dtsi | 6 +++--- > > 7 files changed, 21 insertions(+), 21 deletions(-) > > > > diff --git a/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi b/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi > > index b5756c2..33484d8 100644 > > --- a/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi > > +++ b/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi > > @@ -29,9 +29,9 @@ > > > > backlight { > > compatible = "pwm-backlight"; > > - pwms = <&pwm4 0 5000000>; > > - brightness-levels = <0 4 8 16 32 64 128 255>; > > - default-brightness-level = <7>; > > + pwms = <&pwm4 0 50000>; > > + brightness-levels = <0 20 30 40 50 60 70 80 90 100>; > > + default-brightness-level = <9>; I notice that the intervals are changed from exponential to linear. Is this really wanted here? I expect that the new settings result in huge steps in perceived brightness at low levels and a nearly imperceptible change at the last step. regards Philipp ^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH] ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel 2015-01-22 15:38 ` Philipp Zabel @ 2015-01-26 14:44 ` Robby.Cai at freescale.com 2015-01-27 15:21 ` Philipp Zabel 0 siblings, 1 reply; 4+ messages in thread From: Robby.Cai at freescale.com @ 2015-01-26 14:44 UTC (permalink / raw) To: linux-arm-kernel > -----Original Message----- > From: Philipp Zabel [mailto:p.zabel at pengutronix.de] > Sent: Thursday, January 22, 2015 11:38 PM > To: Shawn Guo > Cc: Cai Robby-R63905; linux-pwm at vger.kernel.org; Eric Nelson; Tim Harvey; > jg1.han at samsung.com; Troy Kisky; thierry.reding at gmail.com; > kernel at pengutronix.de; lee.jones at linaro.org; linux-arm- > kernel at lists.infradead.org > Subject: Re: [PATCH] ARM: dts: imx6qdl: Adjust the brightness setting for > LVDS panel > > Am Dienstag, den 20.01.2015, 19:38 +0800 schrieb Shawn Guo: > > Add LAKML and a few interested people. > > > > Shawn > > > > On Tue, Jan 20, 2015 at 06:22:35PM +0800, Robby Cai wrote: > > > Hannstar XGA panel is used by default on i.MX6QDL Sabre Auto/Lite/SD > > > or derived board. > > > > > > According to its data sheet [1], > > > a) the dimming duty cycle is 20% - 100%. > > > This patch changes the brightness-level from 20 to 100 with step 10 > > > to make it straight-forward. > > > b) the typical dimming frequency is 20KHz. > > > The previous setting is 200Hz. This patch corrects it. > > > > > > [1] > > > http://boundarydevices.com/wp-content/uploads/2013/06/HSD100PXN1-A00 > > > -C11-1.0.pdf > > > > > > Signed-off-by: Robby Cai <r63905@freescale.com> > > > --- > > > arch/arm/boot/dts/imx6qdl-gw52xx.dtsi | 6 +++--- > > > arch/arm/boot/dts/imx6qdl-gw53xx.dtsi | 6 +++--- > > > arch/arm/boot/dts/imx6qdl-gw54xx.dtsi | 6 +++--- > > > arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi | 6 +++--- > > > arch/arm/boot/dts/imx6qdl-sabreauto.dtsi | 6 +++--- > > > arch/arm/boot/dts/imx6qdl-sabrelite.dtsi | 6 +++--- > > > arch/arm/boot/dts/imx6qdl-sabresd.dtsi | 6 +++--- > > > 7 files changed, 21 insertions(+), 21 deletions(-) > > > > > > diff --git a/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi > > > b/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi > > > index b5756c2..33484d8 100644 > > > --- a/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi > > > +++ b/arch/arm/boot/dts/imx6qdl-gw52xx.dtsi > > > @@ -29,9 +29,9 @@ > > > > > > backlight { > > > compatible = "pwm-backlight"; > > > - pwms = <&pwm4 0 5000000>; > > > - brightness-levels = <0 4 8 16 32 64 128 255>; > > > - default-brightness-level = <7>; > > > + pwms = <&pwm4 0 50000>; > > > + brightness-levels = <0 20 30 40 50 60 70 80 90 100>; > > > + default-brightness-level = <9>; > > I notice that the intervals are changed from exponential to linear. > Is this really wanted here? > I expect that the new settings result in huge steps in perceived > brightness at low levels and a nearly imperceptible change at the last > step. > > regards > Philipp No particular reason here. I understand your concern but seems there's no obvious rule. How about add some interpolation, such as <0 52 64 96 128 160 192 224 255> or even more, <0 52 64 80 96 112 128 144 160 176 192 208 224 240 255> Regards, Robby ^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH] ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel 2015-01-26 14:44 ` Robby.Cai at freescale.com @ 2015-01-27 15:21 ` Philipp Zabel 0 siblings, 0 replies; 4+ messages in thread From: Philipp Zabel @ 2015-01-27 15:21 UTC (permalink / raw) To: linux-arm-kernel Am Montag, den 26.01.2015, 14:44 +0000 schrieb Robby.Cai at freescale.com: > > I notice that the intervals are changed from exponential to linear. > > Is this really wanted here? > > I expect that the new settings result in huge steps in perceived > > brightness at low levels and a nearly imperceptible change at the last > > step. > > > > regards > > Philipp > > > No particular reason here. I understand your concern but seems there's no obvious rule. > How about add some interpolation, such as <0 52 64 96 128 160 192 224 255> > or even more, <0 52 64 80 96 112 128 144 160 176 192 208 224 240 255> I just wanted to point out the possible issue. Maybe somebody with the actual panel could sit down and experiment and come up with some visually pleasing steps. regards Philipp ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2015-01-27 15:21 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
[not found] <1421749355-23050-1-git-send-email-r63905@freescale.com>
2015-01-20 11:38 ` [PATCH] ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel Shawn Guo
2015-01-22 15:38 ` Philipp Zabel
2015-01-26 14:44 ` Robby.Cai at freescale.com
2015-01-27 15:21 ` Philipp Zabel
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).