Using the new Cogl API to actually modeset (because we can't
use the DRM API directly without controlling buffer swap), we
can finally have a KMS monitor backend, which means full display
configuration when running on bare metal.
https://bugzilla.gnome.org/show_bug.cgi?id=706308
If, checking the event timestamps, we see that a new configuration
was explicitly requested by an another XRandR client, don't proceed to
apply the intended configuration again, even if looking at the
EDIDs it appears that the outputs changed.
This works around some buggy Xorg drivers (qxl, vbox) that generate
a new serial number everytime the user resizes the host window.
https://bugzilla.gnome.org/show_bug.cgi?id=706735
If we're attempting to reconfigure the CRTCs to the same parameter,
skip the X call, as in some drivers a modeset can take time and
cause flicker.
https://bugzilla.gnome.org/show_bug.cgi?id=706672
The value passed to XRRCrtcSetGamma must be allocated with
XRRAllocGamma (because it relies on the locations of green and blue),
otherwise garbage is sent on the wire.
https://bugzilla.gnome.org/show_bug.cgi?id=706231
We were relying on the XRandR events from the X server to update
the configuration, but we were calling meta_monitor_config_update_current()
immediately after, so the MonitorConfig would be updated with the
old configuration (and we would save that to disk!)
https://bugzilla.gnome.org/show_bug.cgi?id=705670
First disable CRTCs that should be off in the new configuration,
then resize the framebuffer, then enable the new CRTCs.
If we don't do that, and we're making the screen smaller, X complains
with a BadMatch.
https://bugzilla.gnome.org/show_bug.cgi?id=705670
Add "edid-file", if we have one (in the KMS case, where we can point
people to the right sysfs file), or "edid" with inline data.
These are needed by colord to build the default ICC profile for
uncalibrated displays.
https://bugzilla.gnome.org/show_bug.cgi?id=705670
Instead of keeping a forest of if backend else ..., use a subclass
and virtual functions to discriminate between XRandR and the
dummy backend (which lives in the parent class togheter with the
common code)
https://bugzilla.gnome.org/show_bug.cgi?id=705670
