Re: [PATCH] fbdev: workaround for broken X servers

["Antonino A. Daplas" <adaplas@hotpop.com>]

On Saturday 06 November 2004 08:38, Benjamin Herrenschmidt wrote:
> On Fri, 2004-11-05 at 20:55 +0800, Antonino A. Daplas wrote:
> > And make it black is usually done in software (by memsetting the screen
> > with the black color).
> >
> > So why not this:  In fbcon_blank(), if the blank parameter is:
> >
> > 0 - unblank the screen, and call info->fbops->fb_blank(VESA_NO_BLANKING),
> >      then return a nonzero value to force a redraw.
> > 1,2,3,4 - clear the screen with all black
> > 2,3,4 - call info->fbops->fb_blank(blank - 1);
> >
> > Similarly, we can do the same thing in fbmem.c:fb_blank(), but without
> > the software blanking.
> >
> > Drivers will just need to follow the VESA_* defines in fb.h (which
> > happens to be also defined in console.h)
>
> Ah... so radeonfb is correct then, and fb_blank() is not ? X is
> definitely passing +1 values it seems.
>

Well, depends on what approach is adopted:

Most drivers do this:
if (blank)
	switch(blank-1) {
	...
	}

Which means fb_blank() and fbcon_blank() should pass the 
blank parameter to info->fbops->fb_blank() unchanged.

If we adopt the approach of passing (blank -1) to 
info->fbops->fb_blank(), then drivers simply do a:

switch(blank) {
...
}

Currently, fbcon_blank() does the first method (pass blank unchanged),
which means radeonfb is wrong. Adopting the second method will make
radeonfb do the right thing, but will require changes to a lot of drivers.

So, what will it be then?

Tony




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