Messages in this thread | | | From | "Rafael J. Wysocki" <> | Subject | Re: [PATCH] genirq: better describe IRQF_NO_SUSPEND semantics | Date | Tue, 24 Feb 2015 01:26:05 +0100 |
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On Friday, February 20, 2015 02:53:46 PM Mark Rutland wrote: > The IRQF_NO_SUSPEND flag is intended to be used for interrupts required > to be enabled during the suspend-resume cycle. This mostly consists of > IPIs and timer interrupts, potentially including chained irqchip > interrupts if these are necessary to handle timers or IPIs. If an > interrupt does not fall into one of the aforementioned categories, > requesting it with IRQF_NO_SUSPEND is likely incorrect. > > Using IRQF_NO_SUSPEND does not guarantee that the interrupt can wake the > system from a suspended state. For an interrupt to be able to trigger a > wakeup, it may be necessary to program various components of the system. > In these cases it is necessary to use {enable,disabled}_irq_wake. > > Unfortunately, several drivers assume that IRQF_NO_SUSPEND ensures that > an IRQ can wake up the system, and the documentation can be read > ambiguously w.r.t. this property. > > This patch updates the documentation regarding IRQF_NO_SUSPEND to make > this caveat explicit, hopefully making future misuse rarer. Cleanup of > existing misuse will occur as part of later patch series. > > Cc: Boris Brezillon <boris.brezillon@free-electrons.com> > Cc: Ian Campbell <ian.campbell@citrix.com> > Cc: Jonathan Corbet <corbet@lwn.net> > Cc: Peter Zijlstra <peterz@infradead.org> > Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > Cc: Thomas Gleixner <tglx@linutronix.de> > Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Applied to linux-pm.git/linux-next, thanks!
Peter, please let me know if you don't want this to go it.
Rafael
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