[Nouveau] [PATCH xf86-video-nouveau] Do not register hotplug without RandR

[Mariusz Bialonczyk]

When using Xinerama, RandR is automatically disabled, and calling RR
routines will trigger an assert() because the RR keys/resources are
not set, leading to an Xserver abort.

Hotplug makes little sense without RandR, so no need to install a
udev monitor if RandR is not available.

Ported from intel driver, original work by:
Chris Wilson <chris at chris-wilson.co.uk>

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98383
Signed-off-by: Mariusz Bialonczyk <manio at skyboo.net>
---
 src/drmmode_display.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/src/drmmode_display.c b/src/drmmode_display.c
index dd9fa27..ae29d9a 100644
--- a/src/drmmode_display.c
+++ b/src/drmmode_display.c
@@ -1556,6 +1556,15 @@ drmmode_udev_notify(int fd, int notify, void *data)
 }
 #endif
 
+static bool has_randr(void)
+{
+#if HAS_DIXREGISTERPRIVATEKEY
+	return dixPrivateKeyRegistered(rrPrivKey);
+#else
+	return *rrPrivKey;
+#endif
+}
+
 static void
 drmmode_uevent_init(ScrnInfoPtr scrn)
 {
@@ -1564,6 +1573,12 @@ drmmode_uevent_init(ScrnInfoPtr scrn)
 	struct udev *u;
 	struct udev_monitor *mon;
 
+	/* RandR will be disabled if Xinerama is active, and so generating
+	 * RR hotplug events is then forbidden.
+	 */
+	if (!has_randr())
+		return;
+
 	u = udev_new();
 	if (!u)
 		return;
-- 
2.11.0