Re: [Linux-fbdev-devel] mode change policy

[Geert U. <ge...@li...>]

On Thu, 14 Jun 2001, James Simmons wrote:
> > > They return a error instead. Also what is the policy for cards that can't
> > > change modes. Right now most drivers return a -EINVAL if they can't change
> > > a mode. Do we pass back the only mode the driver supports instead of
> > > returning a error? 
> > 
> > If your vesafb runs in 1280x1024x32, setting 800x600x8 must
> > succeed, but do nothing. 
> 
> So a userland app would assume the video mode is 800x600x8 since it worked
> and was passed back it. Of course the results on the screen would be
> totally wrong. Then how is a userland app to know what the real mode is?

Vesafb should return the 1280x1024x32 mode.

> > I still think that we should
> > use highest possible value instead of returning error when we cannot
> > round some value up to next possible value. For example vyres comes
> > to my (and matroxfb) mind ;-)
> 
> I agree. This will especially be true when we support i2c to get monitor
> info. Here will will be fudging the hslen etc for the best fit.

Sounds reasonable. The question is: will it break many things?

The other thing that will break things is changing pixclock from ps to MHz...

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@li...

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds