Re: Control fb problem on 8500

On Mon, 21 Aug 2000, Michel [iso-8859-1] Dänzer wrote:

Geert Uytterhoeven wrote:

quoted

On Mon, 21 Aug 2000, Michel [iso-8859-1] Dänzer wrote:

quoted

That's not even needed, the fbdev driver is just broken. Line 430:

      pScrn->displayWidth = pScrn->virtualX; /* FIXME: might be wrong */

is indeed wrong. virtualX is obvious, but displayWidth should be the
memory pitch of a scanline.

Now you just have to find out where to get the correct value for
displayWidth.

I suppose

    if (fix.line_length)
        pScrn->displayWidth = fix.line_length*8/var.bits_per_pixel;
    else
        pScrn->displayWidth = var.xres_virtual;

should work fine, except on hardware were
fix.line_length*8/var.bits_per_pixel might not be integer (e.g. if
1280x1024x24 mode requires a line_length of 4096).

I've thought of this as well. The problem is that the mode hasn't been
initialized when displayWidth is set and used.

So the X server initializes the internal screen structures before it even knows
that it can use them later?

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds


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