siliconmotion driver hacking [xf86-video-siliconmotion-1.7.4]

[Alan Cox]

> What I would like to do is compile a 'portrait' video driver.
> Essentially, I think I just want to swap the x and y values for each
> pixel, thus creating an output for a display in portrait mode.

See xrandr
 
> I figure that there is a bit more to it than just doing a global
> "replace data_x with data_y and change screen resolutions to 600x800",
> but is there any show stopper that would prevent a plan like this
> working? I guess I would lose the hardware video decoding, but aside
> from that this idea could work, right?

Depends on the hardware and what video acceleration it has. Colour
conversion and scaling are not for example orientation dependent in the
same way as a full offload.