Re: [PATCH/RFC v2 1/3] fbdev: Add FOURCC-based format configuration API

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Geert,

On Monday 29 August 2011 15:09:04 Geert Uytterhoeven wrote:
> On Mon, Aug 29, 2011 at 14:55, Laurent Pinchart wrote:
> >> When will the driver report FB_{TYPE,VISUAL}_FOURCC?
> >>   - When using a mode that cannot be represented in the legacy way,
> > 
> > Definitely.
> > 
> >>   - But what with modes that can be represented? Legacy software cannot
> >>     handle FB_{TYPE,VISUAL}_FOURCC.
> > 
> > My idea was to use FB_{TYPE,VISUAL}_FOURCC only when the mode is
> > configured using the FOURCC API. If FBIOPUT_VSCREENINFO is called with a
> > non-FOURCC format, the driver will report non-FOURCC types and visuals.
> 
> Hmm, two use cases:
>   - The video mode is configured using a FOURCC-aware tool ("fbset on
> steroids").

Such as http://git.ideasonboard.org/?p=fbdev-test.git;a=summary :-)

>     Later the user runs a legacy application.
>       => Do not retain FOURCC across opening of /dev/fb*.

I know about that problem, but it's not that easy to work around. We have no 
per-open fixed and variable screen info, and FB devices can be opened by 
multiple applications at the same time.

>   - Is there an easy way to force FOURCC reporting, so new apps don't have
> to support parsing the legacy formats? This is useful for new apps that
> want to support (a subset of) FOURCC modes only.

Not at the moment.

-- 
Regards,

Laurent Pinchart
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Input]     [Video for Linux]     [Gstreamer Embedded]     [Mplayer Users]     [Linux USB Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Yosemite Backpacking]
  Powered by Linux