Re: [U-Boot] [PATCH v2 3/4] colibri_t20: fix display configuration

On 09/14/2016 04:14 PM, Marcel Ziswiler wrote:

Without this patch the following error will be shown:

stdio_add_devices: Video device failed (ret=-22)

As commit ec5507707a1d1e84056a6c864338f95f6118d3ca (video: tegra: Move to using simple-panel and pwm-backlight) states the Colibri T20 needs updating too which this patch finally attempts doing.

Please note that the current U-Boot implementation requires a dummy GPIO e.g. for a fixed backlight regulator to be explicitly defined in order to work unlike in the Linux kernel where this is taken care of automatically.

diff --git a/arch/arm/dts/tegra20-colibri.dts b/arch/arm/dts/tegra20-colibri.dts

• 	compatible = "regulator-fixed";
  

• 	reg = <0>;
  

• 	regulator-name = "+V3.3";
  

• 	regulator-min-microvolt = <3300000>;
  

• 	regulator-max-microvolt = <3300000>;
  

• 	regulator-always-on;
  

• 	/* Dummy N/C */
  

• 	gpio = <&gpio TEGRA_GPIO(V, 7) GPIO_ACTIVE_HIGH>;
  

NAK while this new DT doesn't actually represent the HW.