gma500: color distortion on framebuffer console unbind

[Patrik Jakobsson]

Hi,

Sorry for late reply. Could be that we're not restoring the state
properly. Not sure though that we guarantee that the framebuffer
contents is valid after unbind. Perhaps take a look at what other
drivers do. I see the same issue on my PSB systems which run SDVO so
it is at least not LVDS related. Unfortunately I wont have time to
look at anything gma500 related at the moment. Feel free to dig into
this and I'll also put it on my todo-list.

Cheers
Patrik


On Mon, Oct 10, 2016 at 10:01 AM, Baruch Siach <baruch at tkos.co.il> wrote:
> Hi Patrik,
>
> I am using the gma500 driver of the latest stable kernel, 4.8.1. My hardware
> is Atom N2600 processor integrated graphics controller, PCI PID: 0x0be1.
> Output is LVDS. The system starts with framebuffer console enabled. Later in
> the boot process I unbind the console with the following command:
>
>   echo 0 > /sys/class/vtconsole/vtcon1/bind
>
> Immediately as the console is unbound some colors on the screen appear
> distorted. The links below show the output of 'fb-test'
> (https://github.com/prpplague/fb-test-app) before and after unbind.
>
>   http://filebin.ca/2xxwlwtBBzBN/display-good.jpg
>   http://filebin.ca/2xxxTyIboJnR/display-bad.jpg
>
> Suggestions are welcome.
>
> Thanks,
> baruch
>
> --
>      http://baruch.siach.name/blog/                  ~. .~   Tk Open Systems
> =}------------------------------------------------ooO--U--Ooo------------{=
>    - baruch at tkos.co.il - tel: +972.2.679.5364, http://www.tkos.co.il -