[PATCHv4 25/29] drm/omap: displays: panel-dpi: Support for handling backlight devices

[Rob Herring]

On Thu, Mar 30, 2017 at 02:15:25PM +0300, Tomi Valkeinen wrote:
> From: Peter Ujfalusi <peter.ujfalusi at ti.com>
> 
> The associated backlight device can be configured via DT by providing the
> phandle to the device.
> 
> If the backlight device is configured, the driver can manage the backligt
> along with the panel's power state, iow it can turn on the backlight when
> the panel is enabled and turn it off when the panel is disabled.
> 
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi at ti.com>
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen at ti.com>
> Cc: devicetree at vger.kernel.org
> ---
>  .../bindings/display/panel/panel-dpi.txt           |  3 ++
>  drivers/gpu/drm/omapdrm/displays/panel-dpi.c       | 37 ++++++++++++++++++++--
>  2 files changed, 38 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/panel/panel-dpi.txt b/Documentation/devicetree/bindings/display/panel/panel-dpi.txt
> index d4add13e592d..6b203bc4d932 100644
> --- a/Documentation/devicetree/bindings/display/panel/panel-dpi.txt
> +++ b/Documentation/devicetree/bindings/display/panel/panel-dpi.txt
> @@ -9,6 +9,7 @@ Optional properties:
>  - enable-gpios: panel enable gpio
>  - reset-gpios: GPIO to control the RESET pin
>  - vcc-supply: phandle of regulator that will be used to enable power to the display
> +- backlight: phandle of the backlight device

Any panel can have a backlight, so please add to panel/panel.txt 
instead.

>  
>  Required nodes:
>  - "panel-timing" containing video timings
> @@ -22,6 +23,8 @@ lcd0: display at 0 {
>          compatible = "samsung,lte430wq-f0c", "panel-dpi";
>          label = "lcd";
>  
> +        backlight = <&backlight>;
> +
>          port {
>              lcd_in: endpoint {
>                      remote-endpoint = <&dpi_out>;