| Message ID | 1458265206-15733-5-git-send-email-heiko@sntech.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi, On Wed, Fri, 18 Mar 2016 Heiko Stuebner <heiko@sntech.de> wrote: > > The panels need a bit of time to actually turn on. If this isn't > observed, this results in problems when trying talk to the panels > and thus produces detection errors. 100ms seem to be a safe value > for the time being. > > Signed-off-by: Heiko Stuebner <heiko@sntech.de> > --- > arch/arm/boot/dts/rk3288-veyron-jaq.dts | 1 + > arch/arm/boot/dts/rk3288-veyron-jerry.dts | 1 + > arch/arm/boot/dts/rk3288-veyron-minnie.dts | 1 + > arch/arm/boot/dts/rk3288-veyron-speedy.dts | 1 + > 4 files changed, 4 insertions(+) I know it was 3 years ago, but any idea how to reproduce the problems you were seeing without this patch? I believe the downstream kernel never had any delay like this and I'm not aware of any issues. I wonder if the need for this extra 100 ms delay is no longer there now that we have: 3157694d8c7f pwm-backlight: Add support for PWM delays proprieties. 5fb5caee92ba pwm-backlight: Enable/disable the PWM before/after LCD enable toggle. 6d5922dd0d60 ARM: dts: rockchip: set PWM delay backlight settings for Veyron
Hi Doug, Am Donnerstag, 20. Juni 2019, 03:27:55 CEST schrieb Doug Anderson: > On Wed, Fri, 18 Mar 2016 Heiko Stuebner <heiko@sntech.de> wrote: > > > > The panels need a bit of time to actually turn on. If this isn't > > observed, this results in problems when trying talk to the panels > > and thus produces detection errors. 100ms seem to be a safe value > > for the time being. > > > > Signed-off-by: Heiko Stuebner <heiko@sntech.de> > > --- > > arch/arm/boot/dts/rk3288-veyron-jaq.dts | 1 + > > arch/arm/boot/dts/rk3288-veyron-jerry.dts | 1 + > > arch/arm/boot/dts/rk3288-veyron-minnie.dts | 1 + > > arch/arm/boot/dts/rk3288-veyron-speedy.dts | 1 + > > 4 files changed, 4 insertions(+) > > I know it was 3 years ago, but any idea how to reproduce the problems > you were seeing without this patch? I believe the downstream kernel > never had any delay like this and I'm not aware of any issues. > > I wonder if the need for this extra 100 ms delay is no longer there > now that we have: > > 3157694d8c7f pwm-backlight: Add support for PWM delays proprieties. > 5fb5caee92ba pwm-backlight: Enable/disable the PWM before/after LCD > enable toggle. > 6d5922dd0d60 ARM: dts: rockchip: set PWM delay backlight settings for Veyron I just did a non-scientific test on my jerry+minnie and yes, simply reverting that patch does not seem to affect display bringup and I still get a prompt. So I guess we could just revert that patch in light of the changes. [patches welcome ;-) ] Heiko
diff --git a/arch/arm/boot/dts/rk3288-veyron-jaq.dts b/arch/arm/boot/dts/rk3288-veyron-jaq.dts index 5c97e31..2123ac2 100644 --- a/arch/arm/boot/dts/rk3288-veyron-jaq.dts +++ b/arch/arm/boot/dts/rk3288-veyron-jaq.dts @@ -61,6 +61,7 @@ pinctrl-names = "default"; pinctrl-0 = <&lcd_enable_h>; regulator-name = "panel_regulator"; + startup-delay-us = <100000>; vin-supply = <&vcc33_sys>; }; diff --git a/arch/arm/boot/dts/rk3288-veyron-jerry.dts b/arch/arm/boot/dts/rk3288-veyron-jerry.dts index 60bd6e9..1a9bef1 100644 --- a/arch/arm/boot/dts/rk3288-veyron-jerry.dts +++ b/arch/arm/boot/dts/rk3288-veyron-jerry.dts @@ -60,6 +60,7 @@ pinctrl-names = "default"; pinctrl-0 = <&lcd_enable_h>; regulator-name = "panel_regulator"; + startup-delay-us = <100000>; vin-supply = <&vcc33_sys>; }; diff --git a/arch/arm/boot/dts/rk3288-veyron-minnie.dts b/arch/arm/boot/dts/rk3288-veyron-minnie.dts index 699beb0..8b16f37 100644 --- a/arch/arm/boot/dts/rk3288-veyron-minnie.dts +++ b/arch/arm/boot/dts/rk3288-veyron-minnie.dts @@ -70,6 +70,7 @@ pinctrl-names = "default"; pinctrl-0 = <&lcd_enable_h>; regulator-name = "panel_regulator"; + startup-delay-us = <100000>; vin-supply = <&vcc33_sys>; }; diff --git a/arch/arm/boot/dts/rk3288-veyron-speedy.dts b/arch/arm/boot/dts/rk3288-veyron-speedy.dts index b34a7b5..e62cdee 100644 --- a/arch/arm/boot/dts/rk3288-veyron-speedy.dts +++ b/arch/arm/boot/dts/rk3288-veyron-speedy.dts @@ -61,6 +61,7 @@ pinctrl-names = "default"; pinctrl-0 = <&lcd_enable_h>; regulator-name = "panel_regulator"; + startup-delay-us = <100000>; vin-supply = <&vcc33_sys>; };
The panels need a bit of time to actually turn on. If this isn't observed, this results in problems when trying talk to the panels and thus produces detection errors. 100ms seem to be a safe value for the time being. Signed-off-by: Heiko Stuebner <heiko@sntech.de> --- arch/arm/boot/dts/rk3288-veyron-jaq.dts | 1 + arch/arm/boot/dts/rk3288-veyron-jerry.dts | 1 + arch/arm/boot/dts/rk3288-veyron-minnie.dts | 1 + arch/arm/boot/dts/rk3288-veyron-speedy.dts | 1 + 4 files changed, 4 insertions(+)