Re: [PATCH 3/3] drm/i915: hot removal notification to HDMI audio driver

[Takashi Iwai <tiwai@suse.de>]

At Mon, 21 Nov 2011 09:58:09 +0800,
Wu Fengguang wrote:
> 
> On Sat, Nov 19, 2011 at 01:46:44AM +0800, Keith Packard wrote:
> > On Fri, 18 Nov 2011 17:37:40 +0800, Wu Fengguang <fengguang.wu@intel.com> wrote:
> > 
> > > However when in X, ->mode_set won't be called at all.  Only
> > > ->get_modes and ->detect are called...
> > 
> > The desktop software will call mode_set when it configures the
> > monitor. Otherwise, it's not being used (and so shouldn't have audio
> > routed to it by default).
> 
> Keith, I experimented playing HDMI audio in X, and during the time
> unplug and plug the monitor. The HDMI audio/graphics all continue to
> work when plugged in the monitor again. Here is the dmesg showed for
> the plug event, no ->mode_set is called at all...

Which desktop system are you using?  At hotplug/unplugging, the kernel
drm issues a udev event, X Intel driver receives it and updates
Xrandr.  Then it's supposed that a daemon like gnome-settings-daemon
receives Xrandr notification and changes the modes appropriately.
Without such a background task, there will be no mode change.


Takashi