diff mbox series

[1/3] ARM: dts: imx6q-logicpd: Shutdown LCD regulator during suspend

Message ID 20190306140402.17122-1-aford173@gmail.com (mailing list archive)
State Mainlined, archived
Commit 6fd6d6f6a2f06cb921a0185072854c3d35d86ff1
Headers show
Series [1/3] ARM: dts: imx6q-logicpd: Shutdown LCD regulator during suspend | expand

Commit Message

Adam Ford March 6, 2019, 2:03 p.m. UTC 
The LCD power sequencer is very finicky.  The backlight cannot
be driven until after the sequencer is done.  Until now, the
regulators were marked with 'regulator-always-on' to make sure
it came up before the backlight.  This patch allows the LCD
regulators to power down and prevent the backlight from being
used again until the sequencer is ready.  This reduces
standby power consumption by ~100mW.

Fixes: 1c207f911fe9 ("ARM: dts: imx: Add support for Logic
PD i.MX6QD EVM")

Signed-off-by: Adam Ford <aford173@gmail.com>

Comments

Shawn Guo March 20, 2019, 12:42 p.m. UTC | #1 
On Wed, Mar 06, 2019 at 08:03:59AM -0600, Adam Ford wrote:
> The LCD power sequencer is very finicky.  The backlight cannot
> be driven until after the sequencer is done.  Until now, the
> regulators were marked with 'regulator-always-on' to make sure
> it came up before the backlight.  This patch allows the LCD
> regulators to power down and prevent the backlight from being
> used again until the sequencer is ready.  This reduces
> standby power consumption by ~100mW.
> 
> Fixes: 1c207f911fe9 ("ARM: dts: imx: Add support for Logic
> PD i.MX6QD EVM")

Fixes tag is more for regressions or serious bugs.  It looks the patch
is more like an improvement though.

Shawn

> 
> Signed-off-by: Adam Ford <aford173@gmail.com>
> 
> diff --git a/arch/arm/boot/dts/imx6q-logicpd.dts b/arch/arm/boot/dts/imx6q-logicpd.dts
> index 45eb0b7f75f8..d96ae54be338 100644
> --- a/arch/arm/boot/dts/imx6q-logicpd.dts
> +++ b/arch/arm/boot/dts/imx6q-logicpd.dts
> @@ -21,6 +21,8 @@
>  
>  	panel-lvds0 {
>  		compatible = "okaya,rs800480t-7x0gp";
> +		power-supply = <&reg_lcd_reset>;
> +		backlight = <&backlight>;
>  
>  		port {
>  			panel_in_lvds0: endpoint {
> @@ -38,7 +40,6 @@
>  		regulator-max-microvolt = <3300000>;
>  		gpio = <&gpio4 17 GPIO_ACTIVE_HIGH>;
>  		enable-active-high;
> -		regulator-always-on;
>  		vin-supply = <&reg_3v3>;
>  		startup-delay-us = <500000>;
>  	};
> @@ -52,7 +53,6 @@
>  		regulator-max-microvolt = <3300000>;
>  		gpio = <&gpio5 2 GPIO_ACTIVE_HIGH>;
>  		enable-active-high;
> -		regulator-always-on;
>  		vin-supply = <&reg_lcd>;
>  	};
>  };
> -- 
> 2.17.1
>
diff mbox series

Patch

diff --git a/arch/arm/boot/dts/imx6q-logicpd.dts b/arch/arm/boot/dts/imx6q-logicpd.dts
index 45eb0b7f75f8..d96ae54be338 100644
--- a/arch/arm/boot/dts/imx6q-logicpd.dts
+++ b/arch/arm/boot/dts/imx6q-logicpd.dts
@@ -21,6 +21,8 @@ 
 
 	panel-lvds0 {
 		compatible = "okaya,rs800480t-7x0gp";
+		power-supply = <&reg_lcd_reset>;
+		backlight = <&backlight>;
 
 		port {
 			panel_in_lvds0: endpoint {
@@ -38,7 +40,6 @@ 
 		regulator-max-microvolt = <3300000>;
 		gpio = <&gpio4 17 GPIO_ACTIVE_HIGH>;
 		enable-active-high;
-		regulator-always-on;
 		vin-supply = <&reg_3v3>;
 		startup-delay-us = <500000>;
 	};
@@ -52,7 +53,6 @@ 
 		regulator-max-microvolt = <3300000>;
 		gpio = <&gpio5 2 GPIO_ACTIVE_HIGH>;
 		enable-active-high;
-		regulator-always-on;
 		vin-supply = <&reg_lcd>;
 	};
 };