Merge branch 'rt/irq' into rt/base

Conflicts:
	kernel/irq/chip.c
	kernel/irq/manage.c

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 81 insertions, 3 deletions

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 474657a806d7..160bfb01c229 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -222,6 +222,34 @@ int set_irq_chip_data(unsigned int irq, void *data)
 }
 EXPORT_SYMBOL(set_irq_chip_data);
 
+/**
+ *	set_irq_nested_thread - Set/Reset the IRQ_NESTED_THREAD flag of an irq
+ *
+ *	@irq:	Interrupt number
+ *	@nest:	0 to clear / 1 to set the IRQ_NESTED_THREAD flag
+ *
+ *	The IRQ_NESTED_THREAD flag indicates that on
+ *	request_threaded_irq() no separate interrupt thread should be
+ *	created for the irq as the handler are called nested in the
+ *	context of a demultiplexing interrupt handler thread.
+ */
+void set_irq_nested_thread(unsigned int irq, int nest)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+	unsigned long flags;
+
+	if (!desc)
+		return;
+
+	atomic_spin_lock_irqsave(&desc->lock, flags);
+	if (nest)
+		desc->status |= IRQ_NESTED_THREAD;
+	else
+		desc->status &= ~IRQ_NESTED_THREAD;
+	atomic_spin_unlock_irqrestore(&desc->lock, flags);
+}
+EXPORT_SYMBOL_GPL(set_irq_nested_thread);
+
 /*
  * default enable function
  */
@@ -299,6 +327,45 @@ static inline void mask_ack_irq(struct irq_desc *desc, int irq)
 	}
 }
 
+/*
+ *	handle_nested_irq - Handle a nested irq from a irq thread
+ *	@irq:	the interrupt number
+ *
+ *	Handle interrupts which are nested into a threaded interrupt
+ *	handler. The handler function is called inside the calling
+ *	threads context.
+ */
+void handle_nested_irq(unsigned int irq)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct irqaction *action;
+	irqreturn_t action_ret;
+
+	might_sleep();
+
+	atomic_spin_lock_irq(&desc->lock);
+
+	kstat_incr_irqs_this_cpu(irq, desc);
+
+	action = desc->action;
+	if (unlikely(!action || (desc->status & IRQ_DISABLED)))
+		goto out_unlock;
+
+	desc->status |= IRQ_INPROGRESS;
+	atomic_spin_unlock_irq(&desc->lock);
+
+	action_ret = action->thread_fn(action->irq, action->dev_id);
+	if (!noirqdebug)
+		note_interrupt(irq, desc, action_ret);
+
+	atomic_spin_lock_irq(&desc->lock);
+	desc->status &= ~IRQ_INPROGRESS;
+
+out_unlock:
+	atomic_spin_unlock_irq(&desc->lock);
+}
+EXPORT_SYMBOL_GPL(handle_nested_irq);
+
 /**
  *	handle_simple_irq - Simple and software-decoded IRQs.
  *	@irq:	the interrupt number
@@ -382,7 +449,10 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc)
 
 	atomic_spin_lock(&desc->lock);
 	desc->status &= ~IRQ_INPROGRESS;
-	if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask)
+
+	if (unlikely(desc->status & IRQ_ONESHOT))
+		desc->status |= IRQ_MASKED;
+	else if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask)
 		desc->chip->unmask(irq);
 out_unlock:
 	atomic_spin_unlock(&desc->lock);
@@ -478,8 +548,13 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
 	kstat_incr_irqs_this_cpu(irq, desc);
 
 	/* Start handling the irq */
-	if (desc->chip->ack)
-		desc->chip->ack(irq);
+	if (unlikely(desc->status & IRQ_ONESHOT)) {
+		desc->status |= IRQ_MASKED;
+		mask_ack_irq(desc, irq);
+	} else {
+		if (desc->chip->ack)
+			desc->chip->ack(irq);
+	}
 
 	/* Mark the IRQ currently in progress.*/
 	desc->status |= IRQ_INPROGRESS;
@@ -572,6 +647,7 @@ __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 		desc->chip = &dummy_irq_chip;
 	}
 
+	chip_bus_lock(irq, desc);
 	atomic_spin_lock_irqsave(&desc->lock, flags);
 
 	/* Uninstall? */
@@ -590,7 +666,9 @@ __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 		desc->depth = 0;
 		desc->chip->startup(irq);
 	}
+
 	atomic_spin_unlock_irqrestore(&desc->lock, flags);
+	chip_bus_sync_unlock(irq, desc);
 }
 EXPORT_SYMBOL_GPL(__set_irq_handler);