On Wed, 13 May 2015, Felipe Balbi wrote:

This brings up a question, actually. What to do with devices which were
already runtime suspended when user initiated suspend-to-ram ? Do we
leave wakeups enabled, or do we revisit device_may_wakeup() and
conditionally runtime_resume the device, disable wakeup, and let its
->suspend() callback be called ?

In theory, the subsystem/device drivers already have code do this.  
They're supposed to, anyway.  The USB host stack does it in
drivers/usb/core/driver.c:choose_wakeup().

Alan Stern