[PATCH v3 1/4] genirq: Reserve the irq when calling irq_set_chip()

[David Daney <ddaney@caviumnetworks.com>]

The helper macros and functions like for_each_active_irq() don't work
unless the irq is in the allocated_irqs set.

In the case of !CONFIG_SPARSE_IRQ, instead of forcing all users of the
irq infrastructure to explicitly call irq_reserve_irq(), do it for
them.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
---
 kernel/irq/chip.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index c9c0601..54d9aab 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -37,6 +37,12 @@ int irq_set_chip(unsigned int irq, struct irq_chip *chip)
 	irq_chip_set_defaults(chip);
 	desc->irq_data.chip = chip;
 	irq_put_desc_unlock(desc, flags);
+	/*
+	 * For !CONFIG_SPARSE_IRQ make the irq show up in
+	 * allocated_irqs.  For the CONFIG_SPARSE_IRQ case, it may
+	 * already be there, and this call is harmless.
+	 */
+	irq_reserve_irq(irq);
 	return 0;
 }
 EXPORT_SYMBOL(irq_set_chip);
-- 
1.7.2.3