linux/Documentation/ABI/testing/usb-uevent

What:		Raise a uevent when a USB Host Controller has died
Date:		2019-04-17
KernelVersion:	5.2
Contact:	[email protected]
Description:	When the USB Host Controller has entered a state where it is no
		longer functional a uevent will be raised. The uevent will
		contain ACTION=offline and ERROR=DEAD.

		Here is an example taken using udevadm monitor -p::

		    KERNEL[130.428945] offline  /devices/pci0000:00/0000:00:10.0/usb2 (usb)
		    ACTION=offline
		    BUSNUM=002
		    DEVNAME=/dev/bus/usb/002/001
		    DEVNUM=001
		    DEVPATH=/devices/pci0000:00/0000:00:10.0/usb2
		    DEVTYPE=usb_device
		    DRIVER=usb
		    ERROR=DEAD
		    MAJOR=189
		    MINOR=128
		    PRODUCT=1d6b/2/414
		    SEQNUM=2168
		    SUBSYSTEM=usb
		    TYPE=9/0/1

Users:		[email protected]