summaryrefslogtreecommitdiff
path: root/kernel/irq
diff options
context:
space:
mode:
authorThomas Gleixner <tglx@linutronix.de>2012-10-16 15:07:49 -0700
committerThomas Gleixner <tglx@linutronix.de>2012-11-01 12:11:31 +0100
commit293a7a0a165c4f8327bbcf396cee9ec672727c98 (patch)
tree6f4dca36e85e5d7cd3648bb322b7db9c29fb8c85 /kernel/irq
parent1e207eb1c3f0e8b690401f02fe08e7b53903f010 (diff)
downloadlwn-293a7a0a165c4f8327bbcf396cee9ec672727c98.tar.gz
lwn-293a7a0a165c4f8327bbcf396cee9ec672727c98.zip
genirq: Provide means to retrigger parent
Attempts to retrigger nested threaded IRQs currently fail because they have no primary handler. In order to support retrigger of nested IRQs, the parent IRQ needs to be retriggered. To fix, when an IRQ needs to be resent, if the interrupt has a parent IRQ and runs in the context of the parent IRQ, then resend the parent. Also, handle_nested_irq() needs to clear the replay flag like the other handlers, otherwise check_irq_resend() will set it and it will never be cleared. Without clearing, it results in the first resend working fine, but check_irq_resend() returning early on subsequent resends because the replay flag is still set. Problem discovered on ARM/OMAP platforms where a nested IRQ that's also a wakeup IRQ happens late in suspend and needed to be retriggered during the resume process. [khilman@ti.com: changelog edits, clear IRQS_REPLAY in handle_nested_irq()] Reported-by: Kevin Hilman <khilman@ti.com> Tested-by: Kevin Hilman <khilman@ti.com> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1350425269-11489-1-git-send-email-khilman@deeprootsystems.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel/irq')
-rw-r--r--kernel/irq/chip.c1
-rw-r--r--kernel/irq/manage.c16
-rw-r--r--kernel/irq/resend.c8
3 files changed, 25 insertions, 0 deletions
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 57d86d07221e..3aca9f29d30e 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -272,6 +272,7 @@ void handle_nested_irq(unsigned int irq)
raw_spin_lock_irq(&desc->lock);
+ desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
kstat_incr_irqs_this_cpu(irq, desc);
action = desc->action;
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 4c69326aa773..d06a396c7ce3 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -616,6 +616,22 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
return ret;
}
+#ifdef CONFIG_HARDIRQS_SW_RESEND
+int irq_set_parent(int irq, int parent_irq)
+{
+ unsigned long flags;
+ struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
+
+ if (!desc)
+ return -EINVAL;
+
+ desc->parent_irq = parent_irq;
+
+ irq_put_desc_unlock(desc, flags);
+ return 0;
+}
+#endif
+
/*
* Default primary interrupt handler for threaded interrupts. Is
* assigned as primary handler when request_threaded_irq is called
diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c
index 6454db7b6a4d..9065107f083e 100644
--- a/kernel/irq/resend.c
+++ b/kernel/irq/resend.c
@@ -74,6 +74,14 @@ void check_irq_resend(struct irq_desc *desc, unsigned int irq)
if (!desc->irq_data.chip->irq_retrigger ||
!desc->irq_data.chip->irq_retrigger(&desc->irq_data)) {
#ifdef CONFIG_HARDIRQS_SW_RESEND
+ /*
+ * If the interrupt has a parent irq and runs
+ * in the thread context of the parent irq,
+ * retrigger the parent.
+ */
+ if (desc->parent_irq &&
+ irq_settings_is_nested_thread(desc))
+ irq = desc->parent_irq;
/* Set it pending and activate the softirq: */
set_bit(irq, irqs_resend);
tasklet_schedule(&resend_tasklet);