Hi! I am using the Rockchip Sapphire board (RK3399) as a desktop computer. Linux kernel version is 4.15.3, as found in ArchLinuxArm. The display is connected to the HDMI port. When idling I execute xset dpms force off to save power. During this state, the usb-disk activity LED flashes continuously. That has been tracked down to uevents sent from the kernel: $ udevadm monitor -kp monitor will print the received events for: KERNEL - the kernel uevent KERNEL[16801.562895] change /devices/platform/display-subsystem/drm/card0 (drm) ACTION=change DEVNAME=/dev/dri/card0 DEVPATH=/devices/platform/display-subsystem/drm/card0 DEVTYPE=drm_minor HOTPLUG=1 MAJOR=226 MINOR=0 SEQNUM=4685 SUBSYSTEM=drm KERNEL[16802.075817] change /devices/platform/display-subsystem/drm/card0 (drm) ACTION=change DEVNAME=/dev/dri/card0 DEVPATH=/devices/platform/display-subsystem/drm/card0 DEVTYPE=drm_minor HOTPLUG=1 MAJOR=226 MINOR=0 SEQNUM=4686 SUBSYSTEM=drm KERNEL[16809.148972] change /devices/platform/display-subsystem/drm/card0 (drm) ACTION=change DEVNAME=/dev/dri/card0 DEVPATH=/devices/platform/display-subsystem/drm/card0 DEVTYPE=drm_minor HOTPLUG=1 MAJOR=226 MINOR=0 SEQNUM=4687 SUBSYSTEM=drm KERNEL[16809.896870] change /devices/platform/display-subsystem/drm/card0 (drm) ACTION=change DEVNAME=/dev/dri/card0 DEVPATH=/devices/platform/display-subsystem/drm/card0 DEVTYPE=drm_minor HOTPLUG=1 MAJOR=226 MINOR=0 SEQNUM=4688 SUBSYSTEM=drm The messages come in pairs: an UnPlug event shortly followed by a Plug event. Then it repeats every 7 seconds. I was not expecting that because the display is not being disconnected and reconnected, never. Is that a bug? Regards, Vicente.
