From 3a79bc63d90750f737ab9d7219bd3091d2fd6d84 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 15 Jul 2019 13:03:20 +0200 Subject: [PATCH] PCI: irq: Introduce rearm_wake_irq() Introduce a new function, rearm_wake_irq(), allowing a wakeup IRQ to be armed for systen wakeup detection again without running any action handlers associated with it after it has been armed for wakeup detection and triggered. That is useful for IRQs, like ACPI SCI, that may deliver wakeup as well as non-wakeup interrupts when armed for systen wakeup detection. In those cases, it may be possible to determine whether or not the delivered interrupt is a systen wakeup one without running the entire action handler (or handlers, if the IRQ is shared) for the IRQ, and if the interrupt turns out to be a non-wakeup one, the IRQ can be rearmed with the help of the new function. Signed-off-by: Rafael J. Wysocki Acked-by: Thomas Gleixner --- include/linux/interrupt.h | 1 + kernel/irq/pm.c | 20 ++++++++++++++++++++ 2 files changed, 21 insertions(+) diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 5b8328a99b2a..0e9cdb3efda7 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -238,6 +238,7 @@ extern void teardown_percpu_nmi(unsigned int irq); /* The following three functions are for the core kernel use only. */ extern void suspend_device_irqs(void); extern void resume_device_irqs(void); +extern void rearm_wake_irq(unsigned int irq); /** * struct irq_affinity_notify - context for notification of IRQ affinity changes diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c index d6961d3c6f9e..8f557fa1f4fe 100644 --- a/kernel/irq/pm.c +++ b/kernel/irq/pm.c @@ -176,6 +176,26 @@ static void resume_irqs(bool want_early) } } +/** + * rearm_wake_irq - rearm a wakeup interrupt line after signaling wakeup + * @irq: Interrupt to rearm + */ +void rearm_wake_irq(unsigned int irq) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL); + + if (!desc || !(desc->istate & IRQS_SUSPENDED) || + !irqd_is_wakeup_set(&desc->irq_data)) + return; + + desc->istate &= ~IRQS_SUSPENDED; + irqd_set(&desc->irq_data, IRQD_WAKEUP_ARMED); + __enable_irq(desc); + + irq_put_desc_busunlock(desc, flags); +} + /** * irq_pm_syscore_ops - enable interrupt lines early *