Hello, Currently I am working on removing legacy power management .suspend() and .resume() callbacks from PCI subsystem. The updates aim to give power management control to PCI core and let drivers do the only device-specific jobs without using any PCI helper functions. I was wondering if similar changes can be applied to the USB subsystem? I explored and found that .suspend() in USB drivers also accept the pm_message_t type argument. Also, .suspend() and .resume() in usb drivers, accept "struct usb_interface *" type argument which seems similar to PCI legacy drivers accepting "struct pci_dev*" type. Moreover, "struct usb_device_driver" seems analogous to "struct pci_driver" as it also has .suspend() and .resume() callback. Also, it has a bitfield "generic_subclass:1" which is described as, " @generic_subclass: if set to 1, the generic USB driver's probe, disconnect, resume and suspend functions will be called in addition to the driver's own, so this part of the setup does not need to be replicated. " So the generic PM, talked about in USB drivers, is similar to PCI one? The non-generic PM in USB is similar to legacy PM in PCI? A similar update for the USB subsystem is possible? --Vaibhav Gupta
