On 19-12-26 14:46:15, Alan Stern wrote: > On Thu, 26 Dec 2019, Guenter Roeck wrote: > > > On shutdown, ehci_power_off() is called unconditionally to power off > > each port, even if it was never called to power on the port. > > For chipidea, this results in a call to ehci_ci_portpower() with a request > > to power off ports even if the port was never powered on. > > This results in the following warning from the regulator code. > > That's weird -- we should always power-on every port during hub > initialization. > > It looks like there's a bug in hub.c:hub_activate(): The line under > HUB_INIT which calls hub_power_on() should call > usb_hub_set_port_power() instead. In fact, the comment near the start > of hub_power_on() is wrong. It says "Enable power on each port", but > in fact it only enables power for ports that had been powered-on > previously (i.e., the port's bit in hub->power_bits was set). > Apparently this got messed up in commit ad493e5e5805 ("usb: add usb > port auto power off mechanism"). > > Now, the chipidea driver may still need to be updated, because > ehci_turn_off_all_ports() will still be called during shutdown and it > will try to power-down all ports, even those which are already powered > down (for example, because the port is suspended). > Hi Alan, When the port is suspended, why it was turned off? If it was turned off, how could respond wakeup event? -- Thanks, Peter Chen