On Tue, Feb 20, 2018 at 10:38 PM, Dominik Brodowski <li...@dominikbrodowski.net> wrote: > On Tue, Feb 20, 2018 at 12:47:27PM +0100, Rafael J. Wysocki wrote: >> From: Rafael J. Wysocki <rafael.j.wyso...@intel.com> >> >> There is a problem with PCMCIA system resume callbacks with respect >> to suspend-to-idle in which the ->suspend_noirq() callback may be >> invoked after the ->resume_noirq() one without resuming the system >> entirely in some cases. This doesn't work for PCMCIA because of >> the lack of symmetry between its system suspend and system resume >> "noirq" callbacks. >> >> The system resume handling in PCMCIA is split between >> socket_early_resume() and socket_late_resume() which are called in >> different phases of system resume and both need to run for >> socket_suspend() (invoked by the system suspend "noirq" callback) >> to work. Specifically, socket_suspend() returns an error when >> called after socket_early_resume() without socket_late_resume(), >> so if the suspend-to-idle core detects a spurious wakeup event and >> attempts to put the system back to sleep, that is aborted by the >> error coming from socket_suspend(). >> >> This design doesn't follow the power management documentation >> stating that the "noirq" resume callback is expected to reverse >> the changes made by the "noirq" suspend one. Moreover, I don't see >> a reason for splitting the PCMCIA socket system resume handling this >> way > > Unless I am mistaken, this split was introduced by commit > 9905d1b411946 . So we should take into account the reasons stated > in that commit message.
Well, I should have done more research, thanks for reminding me about that. I guess I'll need to add one more state flag, then.
