On Wed, 23 Dec 2015, Hayes Wang wrote: > Oliver Neukum [mailto:oneukum@xxxxxxx] > > Sent: Wednesday, December 23, 2015 4:20 PM > [...] > > No, step (2) does not exist. Calls to suspend() and [reset_]resume() > > always balance. Usually a driver shouldn't care about system suspend. > > The way the driver is currently coded will also fail for Port-Power Off. > > It is different with Windows. The Windows would resume the device before > system suspend, if the system suspend follows the autosuspend. > > Would this be a problem? After system suspend, the device may wake up > the system when receiving any packet, not only magic packet. The wake > events are different for system suspend and autosuspend. However, I > couldn't change the wake event, because the autosuspend occurs first, > and the suspend() is only called once. I don't understand why the wakeup conditions are different. It seems to me that the choice of which packets will generate a wakeup ought to depend on the user's selection, not on the kind of suspend. For instance, if the user says that only a magic packet should cause a wakeup then that should be true for both runtime suspend and system suspend. To put it another way, as far as the device is concerned a suspend is just a suspend -- there's no different between a runtime suspend and a system suspend. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
