On Sat, 2 Feb 2013, Stefan Richter wrote: > On Feb 01 Mark Einon wrote: > > On 1 February 2013 21:09, Peter Hurley <[email protected]> wrote: > > >>>> On Jan 29 Alan Stern wrote: > > >>>>> Why does the pci_suspend routine call free_irq() at all? As far as I > > >>>>> know, it's not supposed to do that. Won't the device continue to use > > >>>>> the same IRQ after it is resumed? > > As far as I can tell, it happened to be done that way as a side effect of > how the probe() and resume() methods share code. It has remained like > this since the initial implementation: > http://git.kernel.org/linus/2aef469a35a2
At one point, quite a few years ago, Linus complained about drivers the release IRQs during suspend only to reacquire them during resume. A little refactoring should be able to separate out resource acquisition/release (done only during probe and remove) from activation and shutdown (also done during resume and suspend). > Still, at this point I would like to learn whether .suspend() followed > by .remove() is a valid order of sequence which drivers must support > before I prepare myself to get comfortable with a refactoring of > firewire-ohci's .probe()/.resume()/suspend()/remove(). Obviously, so far > my assumption was that a successful .suspend() can only ever be followed > by .resume(). It depends on the subsystem. Some subsystems do have suspend -> remove transitions and others don't. In general, it's a good idea for drivers to be prepared for removal while the system is asleep. Presumably any hot-unpluggable bus (which includes most of the important buses these days) would have to support it. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
