Created attachment 116319 [details] lshw information about the USB device SUMMARY STEPS TO REPRODUCE 1. insert the usb stick into an usb port of the computer; 2. open the folder of the USB device so to mount it in the KDe Neon or other Os provided by plasma environment; 3. unmount it; 4. the led stay on; 5. udisksctl power-off -b /dev/sdX 6. the command turns off the USB device. OBSERVED RESULT the device doesn't turn off when unmounted; EXPECTED RESULT the device turns off when unmounted; SOFTWARE/OS VERSIONS Windows: MacOS: Linux/KDE Plasma: last (available in About System) KDE Plasma Version: last KDE Frameworks Version: last Qt Version: last ADDITIONAL INFORMATION
I've tested other two USb devices: after having unmounted them the red led stay on. So, I've used udisksctl power-off -b /dev/sdX command to turn off them. My opinion is that the new energy option doesn't work or that is doesn't work on my hardware.
The solution to this annoying issue is to add the SAFELY REMOVE feature in the NOTIFICATION AREA as any Microsoft's OS does. There is no other solution to fix this problem, furthermore this feature is more productive and intelligible. It's necessary to divide the unmount function both from the eject function in the optical drives, and the turning off of the USB device.
This is caused by a hardware bug. The SCSI INQUIRY command allows to determine if the medium in a drive is ejectable or not. This bit should be set for optical drives, tape drives, card readers, ..., but *not* for flash thumb drives. Unfortunately, many thumb drives have this bit set, while USB-SATA bridges fortunately don't. You can see this e.g. in the kernel dmesg output - "sdX: Attached SCSI [removable] disk". But we can not ignore this - if we do, we would also remove card readers. Afterwards, the card slots would be dysfunctional until the computer is rebooted.