[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]
Re: kern/37279: usb and cdrom don't work after resume on PM branch
Some more information on the USB issue.
It appears that the Thinkpad's \_WAK method is responsible for powering
off the external ports. I haven't had success powering them back on, as
the ICH8 spec claims its EHCI doesn't support per-port power controls.
Here are a few theories of what we can try:
1. Before we call AcpiLeaveSleepState on resume (which is responsible
for invoking \_WAK), look for all EHCI devices and if the legacy
capability is present, acquire the semaphore (see
ehci_pci.c:ehci_get_ownership). With any luck, this will prevent
SMI from turning the ports off on us.
2. Failing #1, we need to decypher what method call in \_WAK is
triggering the ports to power off and see if there is an AML method
we can invoke to reverse the effect.
Main Index |
Thread Index |