On Thu, 29 Dec 2005, Nigel Cunningham wrote: > > Often the device-specific resume routine doesn't have the information > > needed for checking whether the device is still there. Such checks are > > done by generic bus-oriented routines. > > > > Yes, the bus's resume handler can do such a check. Why should it bother, > > when other parts of the bus code will detect the device removal in the > > normal course of events? Or alternatively, why shouldn't the bus's resume > > handler simply invoke those other parts of the bus code when it determines > > that a device has been removed? > > I guess because the resume routine is almost certainly the first piece > of code that will try to access the hardware (and possibly choke and die > it it's not there). Obviously we want the resume routine to be robust enough not to die if the device was removed while the system was suspended. :-) As for the rest, however, it simply is not resume()'s job to check whether the device is still there. That job belongs to another piece of code. Consider this: What would happen if the system _hadn't_ been suspended when the device was removed? Why shouldn't the same thing happen if the system _is_ suspended when the device is removed? Alan Stern
