TV output properties

[Alex Deucher]

On Nov 10, 2007 1:07 PM, Jesse Barnes <jbarnes at virtuousgeek.org> wrote:
>
> On Friday, November 09, 2007 10:29 pm Keith Packard wrote:
> > On Fri, 2007-11-09 at 12:20 -0800, Jesse Barnes wrote:
> > > Since bugs.freedesktop.org seems to be down, I'm sending these patches
> > > out for testing to the list.
> > >
> > > They add hue, saturation, contrast and brightness properties to the TV
> > > output and set default values that will hopefully work for people.  In
> > > order to use the new properties though, you'll need the attached patch to
> > > xrandr to properly display and set 8 bit integer values.
> > >
> > > Please test it out and let me know if it works for you.
> > >
> > > How to expose the various properties is still up in the air, right now
> > > they're just exposed as 8 bit values, since that's what goes into the
> > > actual color knob register, but they could be exposed in a friendlier way
> > > (e.g. hue as 0-360 degrees value, saturation and contrast as 2.6 fixed
> > > point values), though that probably wouldn't make much difference to the
> > > user experience. Any opinions?  Is that best left to fancy GUI
> > > applications?
> >
> > Any reason not to expose these as 32-bit values instead? We support
> > range limited 32-bit values, and this might reduce compatibility issues
> > with hardware that needs more bits.
>
> No, we could definitely expose them as larger values.  In fact, the output
> properties we have now (LVDS backlight & TV stuff) should probably be
> generic.  That way they'd be named the same across different types of chips,
> which would make client application development easier.  And the drivers
> could just implement simple callback code to get and set the values, rather
> than having a bunch of RandR & Atom boilerplate...
>
> Maybe the radeon, via, or nouveau guys could chime in here so we could come up
> with a decent subset.

On radeon we expose the following properties for tv out:

        tv_standard: ntsc
        tv_vertical_position: 0 (0x00000000) range:  (-5,5)
        tv_horizontal_position: 0 (0x00000000) range:  (-5,5)
        tv_horizontal_size: 0 (0x00000000) range:  (-5,5)
        load_detection: 0 (0x00000000) range:  (0,1)

tv_standard is a string and the rest are 32 bit values.  We also have
an LVDS backlight property which is a 32 bit value, but it only works
in some laptops due to the what backlight control is implemented by
OEMs, so at the moment, it's not hooked up.

Alex