Merge current Quattro into sudo expiry fix

default/systemd/system/camlink-4k-loopback.service

@@ -0,0 +1,9 @@
+[Unit]
+Description=Create the Cam Link 4K virtual camera
+After=systemd-modules-load.service
+
+[Service]
+# Reruns on every relay start, so a deleted or unloaded device comes back.
+Type=oneshot
+ExecStart=/usr/bin/modprobe v4l2loopback
+ExecStart=/bin/sh -c 'grep -qsx "Cam Link 4K" /sys/devices/virtual/video4linux/*/name || exec v4l2loopback-ctl add -n "Cam Link 4K" -x 1'

default/systemd/system/v4l2-relayd@camlink.service.d/camlink.conf

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+[Unit]
+# udev starts this when the Cam Link 4K appears. Only the device's stop is
+# tied in: a start dependency on it would leave a job waiting whenever the
+# base v4l2-relayd.service is started with no Cam Link attached.
+ConditionPathExists=/dev/camlink4k
+StopPropagatedFrom=dev-camlink4k.device
+Requires=camlink-4k-loopback.service
+After=camlink-4k-loopback.service
+
+[Service]
+RestartSec=2
+# The packaged command line, plus sync=false on the sink. v4l2src stamps each
+# frame with its capture time, so by the time it reaches the sink it is already
+# past due and a synced sink drops every one of them.
+ExecStart=
+ExecStart=/bin/sh -c 'DEVICE=$(grep -l -m1 -E "^${CARD_LABEL}$" /sys/devices/virtual/video4linux/*/name | cut -d/ -f6); exec /usr/bin/v4l2-relayd -i "${VIDEOSRC}" $${SPLASHSRC:+-s "$${SPLASHSRC}"} -o "appsrc name=appsrc caps=video/x-raw,format=${FORMAT},width=${WIDTH},height=${HEIGHT},framerate=${FRAMERATE} ! videoconvert ! v4l2sink name=v4l2sink sync=false device=/dev/$${DEVICE}" $EXTRA_OPTS'

default/udev/elgato-camlink-4k.rules

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+# Keep the Elgato Cam Link 4K's raw capture node away from users and hand it to
+# the v4l2-relayd instance that re-exposes it as a 16:9 virtual camera.
+# Sorted after 70-uaccess adds the tag and before 73-seat-late applies its ACL.
+SUBSYSTEM=="video4linux", ENV{ID_VENDOR_ID}=="0fd9", ENV{ID_MODEL}=="Cam_Link_4K", ENV{ID_V4L_CAPABILITIES}==":capture:", \
+  TAG-="uaccess", OWNER="root", GROUP="root", MODE="0600", SYMLINK+="camlink4k", \
+  TAG+="systemd", ENV{SYSTEMD_ALIAS}="/dev/camlink4k", ENV{SYSTEMD_WANTS}="v4l2-relayd@camlink.service"

default/v4l2-relayd/camlink.conf

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+# Elgato Cam Link 4K relayed as a fixed 16:9 virtual camera. Browser meeting
+# apps send 720p at most; raise WIDTH/HEIGHT (up to 3840x2160) for apps that
+# can use more.
+VIDEOSRC="v4l2src device=/dev/camlink4k"
+FORMAT=NV12
+WIDTH=1280
+HEIGHT=720
+FRAMERATE=30/1
+CARD_LABEL="Cam Link 4K"