Re: [Linux-fbdev-devel] Feature Freeze?

[Carlo E. P. <fl...@fl...>]

	Subject: Re: [Linux-fbdev-devel] Feature Freeze?
	Date: gio, mar 06, 2003 at 09:18:07 +0800

Quoting Antonino Daplas (ad...@po...):

> > > > 2. console resizing using fbset (besides stty)?
> > > 
> > > Nice, if it's not too much work.
> > 
> > :-( I hope to improve fbcon to handle this.
> >  
> 
> If you're really against using fbset to resize the console, then the
> first step is to protect the console from the "dangers" of fbset. 
> Secondly, we can have fbcon_resize() validate the mode instead of just
> blindly calling fb_set_var().  If it's not valid, then it can also fetch
> a working mode for it.  The user can then fine tune the timings using
> fbset afterwards.
> 
> 
> So, do we allow fbcon to handle mode validating and fetching, or do we
> just leave all this to fbdev? At least let's bring out some ideas on how
> to go about doing this.  Having a working idea, even if dumb, should
> interest other developers in contributing. 

I see there currently is much activity on the list. I would like to
present the point of view of a heavy framebuffer user: I write
multimedia code for artists, and I generally generate video via the
framebuffer layer, and trusted old matrox cards (from the Millennium
II to the G550). The general process is:

- open the framebuffer unit
- FBIOGET_VSCREENINFO
- change the appropriate values in fb_var_screeninfo
- FBIOPUT_VSCREENINFO
- mmap
- happily write pixels to the memory area

This, multiplied for all the video heads that I use within the same
program (up to 5 per PC, up to now, *including* the console screen -
in this case I control the machine from a network connection).

I am especially in need to change the BPP value (often using 16BPP
mode), and in a couple of occasions (the latest 2 weeks ago) I had to
feed the output of old G200's to large monitors who are only capable
of TV resolution. This means setting the framebuffer to 768x576 (PAL)
and *interlaced*. The framebuffer model that still survives in 2.4
allows me to obtain all this. 

I am not much familiar with all the terminology that is used for the
new layer. Actually, this framebuffer revolution is what keeps me from
enjoying (!) the kernel bleeding edge, as I used to do since almost 10
years ago. 

Can I poll the list's huge knowledge to find out if and how I can
obtain the same result with the new layer?

Thanks a lot in advance...

Carlo 

-- 
  *         Se la Strada e la sua Virtu' non fossero state messe da parte,
* K * Carlo E. Prelz - fl...@fl...             che bisogno ci sarebbe
  *               di parlare tanto di amore e di rettitudine? (Chuang-Tzu)