From mboxrd@z Thu Jan 1 00:00:00 1970 From: adharmap@codeaurora.org (Abhijeet Dharmapurikar) Date: Fri, 11 Mar 2011 12:06:53 -0800 Subject: [Qualcomm PM8921 MFD v2 2/6] mfd: pm8xxx: Add irq support In-Reply-To: References: <1299564590-30116-1-git-send-email-adharmap@codeaurora.org> <1299564590-30116-3-git-send-email-adharmap@codeaurora.org> <4D770E47.6050402@codeaurora.org> <4D79A85D.8000301@codeaurora.org> <4D7A71B9.9000306@codeaurora.org> Message-ID: <4D7A80DD.7000909@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Thomas Gleixner wrote: > On Fri, 11 Mar 2011, Abhijeet Dharmapurikar wrote: >>>> Yes however while updating the code I noticed that I would need to keep >>>> account of all the interrupts enabled and all the interrupts marked >>>> wakeup. >>>> This aids in switching to the wakeup set in the suspend callback and the >>>> enabled set in the resume callback. I will update the resume callback to >>>> enable the interrupts in irqs_allowed(the local state storage) in the next >>>> patch (my current patch does not do that). >>>> >>>> IOW I need to keep the local state storage. >>> Wrong. The interrupts are disabled and reenabled by the core code and >>> not by some extra suspend/resume callbacks in your driver. The core >>> checks those marked as IRQ_WAKE, the wake callback to the irq chip is >>> only there if you need to set up some hardware register in order to >>> make the wake functionality work. So again, you don't need local state >>> as the core tracks the state for you. >> Help me understand this, the core code calls disable on all the interrupts >> while going to suspend. Notice that I have no disable callback, which means >> those interrupts remain unmasked. >> >> The genirq code does not mask the interrupt while going to suspend, it only >> calls disable(), which I understand should not mask the interrupt for >> check_wakeup_irqs() to work. >> >> If I don't mask that accelerometer interrupts in the interrupt controller's >> suspend() the phone will wakeup every time the user moves around, draining the >> battery unnecessarily. > > That's why we mark the interrupts which can wake up from suspend with > set_wake() so you can configure your hardware accordingly. That's how > all other stuff works, at least how it's supposed to work. > > If there is no way to tell the interrupt controller which interrupts > are wakeup sources and which are not, then working around it with > local state and private suspend/resume functions is the WRONG answer. > > Simply because this kind of misdesigned hardware will creep up over > and over and we want to handle these cases in the core. Even for a > sinlge instance like yours solving it in the core is the right thing > to do, because it's a ~3 lines patch to the core code to get this > done. ~3 lines patch to the code sounds promising. Please tell me how? -- -- Sent by an employee of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.