Re: conflicts between fbcon and user-mode fbdev clients

On Thu, Dec 10, 2009 at 20:43, Bernie Thompson [off-list ref] wrote:

On Thu, Dec 10, 2009 at 11:02 AM, James Simmons [off-list ref] wrote:

quoted

That shouldn't happen. In the xorg.conf do you have in the

Option UseFBDev "True"

That option appears to have no effect (have tried both ways).  Do you
know who parses it?  Couldn't find it in core xserver.

The DisplayLink support is still very rough, but it's currently using
its own X server driver
(http://libdlo.freedesktop.org/wiki/xf86-driver-displaylink), which
has some IOCTLs to its framebuffer driver, including a mode setting
IOCTL.

If the arbitration between fbdev clients is intended to happen at the
point of mode setting, rather than at open(), that would explain the
problem.  Are there any old posts or docs which describe how
arbitration is handled for the fbdev driver and multiple clients?

Usually the X server locks the VT (virtual terminal) using an ioctl,
and uses another ioctl to switch the VT to graphics mode, so fbcon
will stop drawing to it.

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