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commit5090ac9191upstream. The PMIC GLINK driver is currently generating DisplayPort hotplug notifications whenever something is connected to (or disconnected from) a port regardless of the type of notification sent by the firmware. These notifications are forwarded to user space by the DRM subsystem as connector "change" uevents: KERNEL[1556.223776] change /devices/platform/soc@0/ae00000.display-subsystem/ae01000.display-controller/drm/card0 (drm) ACTION=change DEVPATH=/devices/platform/soc@0/ae00000.display-subsystem/ae01000.display-controller/drm/card0 SUBSYSTEM=drm HOTPLUG=1 CONNECTOR=36 DEVNAME=/dev/dri/card0 DEVTYPE=drm_minor SEQNUM=4176 MAJOR=226 MINOR=0 On the Lenovo ThinkPad X13s and T14s, the PMIC GLINK firmware sends two identical notifications with orientation information when connecting a charger, each generating a bogus DRM hotplug event. On the X13s, two such notification are also sent every 90 seconds while a charger remains connected, which again are forwarded to user space: port = 1, svid = ff00, mode = 255, hpd_state = 0 payload = 01 00 00 00 00 00 00 ff 00 00 00 00 00 00 00 00 Note that the firmware only sends on of these when connecting an ethernet adapter. Fix the spurious hotplug events by only forwarding hotplug notifications for the Type-C DisplayPort service id. This also reduces the number of uevents from four to two when an actual DisplayPort altmode device is connected: port = 0, svid = ff01, mode = 2, hpd_state = 0 payload = 00 01 02 00 f2 0c 01 ff 03 00 00 00 00 00 00 00 port = 0, svid = ff01, mode = 2, hpd_state = 1 payload = 00 01 02 00 f2 0c 01 ff 43 00 00 00 00 00 00 00 Fixes:080b4e2485("soc: qcom: pmic_glink: Introduce altmode support") Cc: stable@vger.kernel.org # 6.3 Cc: Bjorn Andersson <andersson@kernel.org> Reported-by: Clayton Craft <clayton@craftyguy.net> Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Acked-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Tested-by: Clayton Craft <clayton@craftyguy.net> Link: https://lore.kernel.org/r/20250324132448.6134-1-johan+linaro@kernel.org Signed-off-by: Bjorn Andersson <andersson@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>