Re: [Linux-fbdev-devel] [PATCH] fbdev: find mode with highest refresh rate in fb_find_mode()

[Michal Januszewski <spock@gentoo.org>]

On Wed, Jul 18, 2007 at 11:18:15PM +0800, Antonino A. Daplas wrote:

> > > Currently if the refresh rate is not specified fb_find_mode() returns
> > > the first known video mode with the requested resoluion, which provides
> > > no guarantees wrt the refresh rate.  Change this so that the mode with
> > > the highest refresh rate is returned instead.
> > 
> > What refresh rate it sets when used on card or monitor without DDC?
>
> Yes, I noted this also while reviewing patches.  fb_find_mode() is used
> predominantly with the 'generic' modedb which contains modes that are
> not specific to the card or monitor.  And fb_try_mode() is not a
> guarantee that the returned refresh rate will be safe (we have a lot of
> drivers that do not check the timings against the display capabilities).
> 
> It would be best that fb_find_mode() return the safest refresh rate
> (60Hz) instead of the highest.

How about modifying it so that it looks for a mode with the highest
refresh rate if either a non-generic modedb is used or
info.monspecs.{vfmin,vfmax,hfmin,hfmax,dclkmax} are all non-zero,
and for a mode with refresh rate closest to 60 Hz otherwise?

I'm sorry for the delayed reply.

Best regards.
-- 
Michal Januszewski                              JID: spock@im.gentoo.org
Gentoo Linux Developer                    http://people.gentoo.org/spock

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/