Hi,
On Mon, Jul 29, 2019 at 10:45:26PM +0200, Pavel Machek wrote:
> Hi!
>
> > On Mon, Jul 29, 2019 at 03:55:23PM +0200, Pavel Machek wrote:
> > > > Oh and the new backlight module comes up blanked right now so it
> > > > needs to be manually enabled via sysfs.
> > >
> > > Or you can enable ledtrig-backlight and apply this.
> > >
> > > (I know, we need better solution).
> >
> > https://lore.kernel.org/lkml/20190717141514.21171-1-jjhiblot@ti.com/
> >
> > The above patchset is the proper solution. It is a backlight
> > driver, which takes the LED driver as input and exposes a
> > proper backlight device. This makes it possible to reference
> > the backlight in DT:
> >
> > ----------------
> > led-node {
> > blabla;
> > };
> >
> > backlight-node {
> > blabla;
> > led = <&led-node>;
> > };
> >
> > panel-node {
> > backlight = <&backlight-node>;
> > };
> > ----------------
>
> Hmm, I guess I should try to get it to work.
>
> I came up with this, and ... it does not work. If you see
> something obviously wrong, tell me.
DT change looks sensible to me. I did not yet do any test myself.
I'm too busy with converting the omapdrm DSI code to drm_panel.
-- Sebastian
>
> Thanks,
> Pavel
>
> diff --git a/arch/arm/boot/dts/omap4-droid4-xt894.dts b/arch/arm/boot/dts/omap4-droid4-xt894.dts
> index 62af1b8..0195580 100644
> --- a/arch/arm/boot/dts/omap4-droid4-xt894.dts
> +++ b/arch/arm/boot/dts/omap4-droid4-xt894.dts
> @@ -202,12 +202,22 @@
> };
> };
>
> + backlight: backlight {
> + compatible = "led-backlight";
> +
> + leds = <&backlight_led>;
> + brightness-levels = <0 4 8 16 32 64 128 255>;
> + default-brightness-level = <6>;
> + };
> +
> lcd0: display {
> compatible = "panel-dsi-cm";
> label = "lcd0";
> vddi-supply = <&lcd_regulator>;
> reset-gpios = <&gpio4 5 GPIO_ACTIVE_HIGH>; /* gpio101 */
>
> + backlight = <&backlight>;
> +
> width-mm = <50>;
> height-mm = <89>;
>
> @@ -417,12 +427,11 @@
> ramp-up-us = <1024>;
> ramp-down-us = <8193>;
>
> - led@0 {
> + backlight_led: led@0 {
> reg = <0>;
> led-sources = <2>;
> ti,led-mode = <0>;
> label = ":backlight";
> - linux,default-trigger = "backlight";
> };
>
> led@1 {
>
>
> --
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
::
Re: [maemo-leste] Backlight on Droi…
