On Sat, 7 Jul 2012, Rafael J. Wysocki wrote: > > What is the right way to handle the runtime PM enable/disable in a > > failed probe attempt? > > I would recommend using pm_runtime_disable() and then either > pm_runtime_set_active() or pm_runtime_set_suspended() depending on what the > real power state of the device is at this point. > > Anyway, you can't force the device into a low-power state using runtime PM > after a failing probe, at least in general. Right. About the best you could do would be to call the appropriate runtime_suspend method directly, instead of going through the runtime PM core. However, if the probe is failing then there's no reason to think the runtime_suspend method will work. Basically, on the platform bus, if you don't have a driver for a device (which you don't, if the probe routine fails) then you can't do runtime PM on it. But what if the device belongs to a PM domain? Putting the entire domain back into a low-power state might have the desired effect -- but the probe routine wouldn't be able to do this. The platform subsystem would have to take care of it somehow. Alan Stern
