On Tue, 28 Apr 2020, Dave Mielke wrote: > [quoted lines by Greg KH on 2020/04/27 at 12:30 +0200] > > >Have a udev rule that turns autosuspend off for each specific USB device > >that you know does not work with autosuspend. > > Yes, thanks, that should work. I have another question, though. Our code first > tries to write "-1" to power/autosuspend, and then, if that fails, it writes > "0". I'm guessing that "-1" was an older way (but I've forgotten). How can a > udev rule be written to accommodate that? See the entry for "/sys/bus/usb/devices/.../power/autosuspend" in Documentation/ABI/stable/sysfs-bus-usb, or the corresponding entry for "/sys/devices/.../power/autosuspend_delay_ms" in Documentation/ABI/testing/sysfs-devices-power. In short, -1 means "don't autosuspend", whereas 0 means "autosuspend as soon as possible". Alan Stern
