ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel
Subsystems (3)
PATCH 1/1 ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel
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
--- 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(-)
arch/arm/boot/dts/imx6qdl-gw52xx.dtsi +3 -3
@@ -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 {
arch/arm/boot/dts/imx6qdl-gw53xx.dtsi +3 -3
@@ -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 {
arch/arm/boot/dts/imx6qdl-gw54xx.dtsi +3 -3
@@ -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 {
arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi +3 -3
@@ -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"; };
arch/arm/boot/dts/imx6qdl-sabreauto.dtsi +3 -3
@@ -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"; }; };
arch/arm/boot/dts/imx6qdl-sabrelite.dtsi +3 -3
@@ -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"; };
arch/arm/boot/dts/imx6qdl-sabresd.dtsi +3 -3
@@ -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"; };
Signature · 1 line
1.9.1
PATCH 1/1 ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel
Add LAKML and a few interested people.
Shawn
Quoted 146 lines · Robby Cai
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.pdfSigned-off-by Robby Cai <[email protected]>--- 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(-)arch/arm/boot/dts/imx6qdl-gw52xx.dtsi +3
-3@@ -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 {arch/arm/boot/dts/imx6qdl-gw53xx.dtsi +3
-3@@ -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 {arch/arm/boot/dts/imx6qdl-gw54xx.dtsi +3
-3@@ -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 {arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi +3
-3@@ -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"; };arch/arm/boot/dts/imx6qdl-sabreauto.dtsi +3
-3@@ -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"; }; };arch/arm/boot/dts/imx6qdl-sabrelite.dtsi +3
-3@@ -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"; };arch/arm/boot/dts/imx6qdl-sabresd.dtsi +3
-3@@ -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"; };Signature · 1 line
1.9.1
PATCH 1/1 ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel
Am Dienstag, den 20.01.2015, 19:38 +0800 schrieb Shawn Guo:
Quoted 35 lines
Add LAKML and a few interested people.
Shawn
Quoted 30 lines · Robby Cai
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.pdfSigned-off-by Robby Cai <[email protected]>--- 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(-)arch/arm/boot/dts/imx6qdl-gw52xx.dtsi +0
-0@@ -29,9 +29,9 @@
Quoted 8 lines
arch/arm/boot/dts/imx6qdl-gw52xx.dtsi line 34
Quoted 8 lines
arch/arm/boot/dts/imx6qdl-gw52xx.dtsi +3
-3backlight { 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
PATCH 1/1 ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel
Quoted 66 lines
-----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 panelAm Dienstag, den 20.01.2015, 19:38 +0800 schrieb Shawn Guo:
Quoted 37 lines
Add LAKML and a few interested people.
Shawn
Quoted 32 lines · Robby Cai
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.pdfSigned-off-by Robby Cai <[email protected]>--- 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(-)arch/arm/boot/dts/imx6qdl-gw52xx.dtsi +0
-0@@ -29,9 +29,9 @@Quoted 8 lines
arch/arm/boot/dts/imx6qdl-gw52xx.dtsi line 34
Quoted 8 lines
arch/arm/boot/dts/imx6qdl-gw52xx.dtsi +3
-3backlight { 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.
Quoted 2 lines
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
PATCH 1/1 ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel
Am Montag, den 26.01.2015, 14:44 +0000 schrieb Robby.Cai at freescale.com:
Quoted 6 lines
Quoted 6 lines
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.
Quoted 7 lines
Quoted 2 lines
regards
PhilippNo 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