6 files changed, 116 insertions, 7 deletions

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 0c9cb63e6895..c68bffd182bb 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -117,6 +117,15 @@ extern void disable_irq_nosync(unsigned int irq);
 extern void disable_irq(unsigned int irq);
 extern void enable_irq(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);
+#ifdef CONFIG_PM_SLEEP
+extern int check_wakeup_irqs(void);
+#else
+static inline int check_wakeup_irqs(void) { return 0; }
+#endif
+
 #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
 
 extern cpumask_var_t irq_default_affinity;
diff --git a/include/linux/irq.h b/include/linux/irq.h
index 9c62fbe2ef30..974890b3c52f 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -67,6 +67,7 @@ typedef	void (*irq_flow_handler_t)(unsigned int irq,
 #define IRQ_SPURIOUS_DISABLED   0x00800000      /* IRQ was disabled by the spurious trap */
 #define IRQ_MOVE_PCNTXT         0x01000000      /* IRQ migration from process context */
 #define IRQ_AFFINITY_SET        0x02000000      /* IRQ affinity was set from userspace*/
+#define IRQ_SUSPENDED           0x04000000      /* IRQ has gone through suspend sequence */
 
 #ifdef CONFIG_IRQ_PER_CPU
 # define CHECK_IRQ_PER_CPU(var) ((var) & IRQ_PER_CPU)
diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile
index 4dd5b1edac98..3394f8f52964 100644
--- a/kernel/irq/Makefile
+++ b/kernel/irq/Makefile
@@ -4,3 +4,4 @@ obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o
 obj-$(CONFIG_PROC_FS) += proc.o
 obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o
 obj-$(CONFIG_NUMA_MIGRATE_IRQ_DESC) += numa_migrate.o
+obj-$(CONFIG_PM_SLEEP) += pm.o
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index ee1aa9f8e8b9..01ce20eab38f 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -12,6 +12,8 @@ extern void compat_irq_chip_set_default_handler(struct irq_desc *desc);
 
 extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
                 unsigned long flags);
+extern void __disable_irq(struct irq_desc *desc, unsigned int irq, bool susp);
+extern void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume);
 
 extern struct lock_class_key irq_desc_lock_class;
 extern void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 6458e99984c0..1516ab77355c 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -162,6 +162,20 @@ static inline int setup_affinity(unsigned int irq, struct irq_desc *desc)
 }
 #endif
 
+void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend)
+{
+        if (suspend) {
+                if (!desc->action || (desc->action->flags & IRQF_TIMER))
+                        return;
+                desc->status |= IRQ_SUSPENDED;
+        }
+
+        if (!desc->depth++) {
+                desc->status |= IRQ_DISABLED;
+                desc->chip->disable(irq);
+        }
+}
+
 /**
  *      disable_irq_nosync - disable an irq without waiting
  *      @irq: Interrupt to disable
@@ -182,10 +196,7 @@ void disable_irq_nosync(unsigned int irq)
                 return;
 
         spin_lock_irqsave(&desc->lock, flags);
-        if (!desc->depth++) {
-                desc->status |= IRQ_DISABLED;
-                desc->chip->disable(irq);
-        }
+        __disable_irq(desc, irq, false);
         spin_unlock_irqrestore(&desc->lock, flags);
 }
 EXPORT_SYMBOL(disable_irq_nosync);
@@ -215,15 +226,21 @@ void disable_irq(unsigned int irq)
 }
 EXPORT_SYMBOL(disable_irq);
 
-static void __enable_irq(struct irq_desc *desc, unsigned int irq)
+void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
 {
+        if (resume)
+                desc->status &= ~IRQ_SUSPENDED;
+
         switch (desc->depth) {
         case 0:
+ err_out:
                 WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq);
                 break;
         case 1: {
                 unsigned int status = desc->status & ~IRQ_DISABLED;
 
+                if (desc->status & IRQ_SUSPENDED)
+                        goto err_out;
                 /* Prevent probing on this irq: */
                 desc->status = status | IRQ_NOPROBE;
                 check_irq_resend(desc, irq);
@@ -253,7 +270,7 @@ void enable_irq(unsigned int irq)
                 return;
 
         spin_lock_irqsave(&desc->lock, flags);
-        __enable_irq(desc, irq);
+        __enable_irq(desc, irq, false);
         spin_unlock_irqrestore(&desc->lock, flags);
 }
 EXPORT_SYMBOL(enable_irq);
@@ -511,7 +528,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
          */
         if (shared && (desc->status & IRQ_SPURIOUS_DISABLED)) {
                 desc->status &= ~IRQ_SPURIOUS_DISABLED;
-                __enable_irq(desc, irq);
+                __enable_irq(desc, irq, false);
         }
 
         spin_unlock_irqrestore(&desc->lock, flags);
diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c
new file mode 100644
index 000000000000..638d8bedec14
--- /dev/null
+++ b/kernel/irq/pm.c
@@ -0,0 +1,79 @@
+/*
+ * linux/kernel/irq/pm.c
+ *
+ * Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
+ *
+ * This file contains power management functions related to interrupts.
+ */
+
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+
+#include "internals.h"
+
+/**
+ * suspend_device_irqs - disable all currently enabled interrupt lines
+ *
+ * During system-wide suspend or hibernation device interrupts need to be
+ * disabled at the chip level and this function is provided for this purpose.
+ * It disables all interrupt lines that are enabled at the moment and sets the
+ * IRQ_SUSPENDED flag for them.
+ */
+void suspend_device_irqs(void)
+{
+        struct irq_desc *desc;
+        int irq;
+
+        for_each_irq_desc(irq, desc) {
+                unsigned long flags;
+
+                spin_lock_irqsave(&desc->lock, flags);
+                __disable_irq(desc, irq, true);
+                spin_unlock_irqrestore(&desc->lock, flags);
+        }
+
+        for_each_irq_desc(irq, desc)
+                if (desc->status & IRQ_SUSPENDED)
+                        synchronize_irq(irq);
+}
+EXPORT_SYMBOL_GPL(suspend_device_irqs);
+
+/**
+ * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs()
+ *
+ * Enable all interrupt lines previously disabled by suspend_device_irqs() that
+ * have the IRQ_SUSPENDED flag set.
+ */
+void resume_device_irqs(void)
+{
+        struct irq_desc *desc;
+        int irq;
+
+        for_each_irq_desc(irq, desc) {
+                unsigned long flags;
+
+                if (!(desc->status & IRQ_SUSPENDED))
+                        continue;
+
+                spin_lock_irqsave(&desc->lock, flags);
+                __enable_irq(desc, irq, true);
+                spin_unlock_irqrestore(&desc->lock, flags);
+        }
+}
+EXPORT_SYMBOL_GPL(resume_device_irqs);
+
+/**
+ * check_wakeup_irqs - check if any wake-up interrupts are pending
+ */
+int check_wakeup_irqs(void)
+{
+        struct irq_desc *desc;
+        int irq;
+
+        for_each_irq_desc(irq, desc)
+                if ((desc->status & IRQ_WAKEUP) && (desc->status & IRQ_PENDING))
+                        return -EBUSY;
+
+        return 0;
+}