On Tue, Nov 2, 2010 at 3:01 AM, Pedro DeKeratry <pdekera...@gmail.com> wrote: > First let me describe the behavior that prompted my questions. This is > on a laptop running Ubuntu Desktop 10.10 and the xorg.conf is > configured to run a mutli-display using the external HDMI and external > VGA ports, thus the laptop screen is blank/off. If I unplug the HDMI > connection the system does some display switching and my laptop screen > turns on. When I plug the HDMI connection back in nothing happens. A > couple of xrandr commands later and I can get the HDMI output > displaying how it was originally. Suppose though that instead of > issuing the xrandr commands to bring the external HDMI connection back > up after plugging it in, I reboot the machine instead. Since my > /etc/xorg.conf is unchanged I would expect that both my external > monitors come up, however, the laptop screen comes on instead of my > HDMI external connection which is now shown as disconnected. To get > things back the way they were I can either used xrandr like previously > or the ATI gfx menu options. Note that this only happens with regards > to my HDMI connection because I think the laptop screen and the HDMI > share the TMDS graphics hardware ( Assuming my understanding of these > things is correct ; ) .) Unplugging the VGA doesn't create any auto > switching response.
Your laptop screen and hdmi port are likely using separate encoders, but you only have 2 display controllers so you can only use two displays at a time. Digital connectors (DVI, HDMI, DP) have a hot plug pin that can generate an interrupt when the monitor is connected or disconnected, but older analog monitors (VGA, TV) do not. > > So, with that said: > > Is is xrandr that does the auto switching from ext. HDMI to laptop > automatically when HDMI monitor signal is lost? Or is that the gfx > drivers or some other X program? ( I'd like to disable it if possible > ) When a connect/disconnect interrupt is generated the drm sends an event to userspace which can then do something with the event. In your case I think it just runs 'xrandr --auto' when it receives the event, but you can have it do whatever you want. > > Is it xrandr that is saving some kind of persistent configuration > settings somewhere that overrides my xorg.conf file at the next > reboot? I couldn't find any sort of conf file anywhere related to > this. Googling xrandr info doesn't show much except same man pages. > randr does not save any persistent state. if you want to force a particular setup, you need to specify it in your xorg.conf or via xrandr commands in your desktop startup scripts. > Is xrandr scheduled to replace xorg.conf altogether? I've noticed that > my xorg.conf really is pretty much as minimal as you can get. In > previous Linux systems I've had much more intricate xorg.conf files > with a lot more details filled in. Other than loading the driver for > the gfx card, it seems like everything else can be pretty much done > through xrandr. Am I understanding correctly where xrandr is headed in > the Linux/X world? xrandr is just a utility to dynamically reconfigure your displays. xorg.conf is for specifying specific settings. See this page for info an using xrandr and specifying display settings in your xorg.conf: http://wiki.debian.org/XStrikeForce/HowToRandR12 Alex > > --Pedro > > On Sat, Oct 30, 2010 at 4:03 AM, Jeremy Huddleston > <jerem...@freedesktop.org> wrote: >> This would be a good place... >> >> On Oct 29, 2010, at 21:07, Pedro DeKeratry wrote: >> >>> Hi everyone, >>> >>> Is this the appropriate place to ask questions about the xrandr >>> command line utility in order to understand how it interacts with my >>> system environment at large or is such a question better suited to a >>> distro specific mailing list? >>> >>> --Pedro >>> _______________________________________________ >>> xorg@lists.freedesktop.org: X.Org support >>> Archives: http://lists.freedesktop.org/archives/xorg >>> Info: http://lists.freedesktop.org/mailman/listinfo/xorg >>> Your subscription address: jerem...@freedesktop.org >> >> > _______________________________________________ > xorg@lists.freedesktop.org: X.Org support > Archives: http://lists.freedesktop.org/archives/xorg > Info: http://lists.freedesktop.org/mailman/listinfo/xorg > Your subscription address: alexdeuc...@gmail.com > _______________________________________________ xorg@lists.freedesktop.org: X.Org support Archives: http://lists.freedesktop.org/archives/xorg Info: http://lists.freedesktop.org/mailman/listinfo/xorg Your subscription address: arch...@mail-archive.com