On Wed, 2015-12-23 at 09:20 +0000, 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. That is indeed a problem and I need to think a bit about finding a good solution. If you are happy with an inelegant solution, you can use a pm_notifier, which will tell you that the system is going to suspend. This is documented: https://www.kernel.org/doc/Documentation/power/notifiers.txt HTH Oliver -- 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
