genirq: Generic chip: Cache per irq bit mask

Cache the per irq bit mask instead of recalculating it over and over.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jean-Francois Moine <moinejf@free.fr>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Gerlando Falauto <gerlando.falauto@keymile.com>
Cc: Rob Landley <rob@landley.net>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: http://lkml.kernel.org/r/20130506142539.227119865@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/irq.h b/include/linux/irq.h
index 7f1f015..d5fc7f5 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -119,6 +119,7 @@
 
 /**
  * struct irq_data - per irq and irq chip data passed down to chip functions
+ * @mask:		precomputed bitmask for accessing the chip registers
  * @irq:		interrupt number
  * @hwirq:		hardware interrupt number, local to the interrupt domain
  * @node:		node index useful for balancing
@@ -138,6 +139,7 @@
  * irq_data.
  */
 struct irq_data {
+	u32			mask;
 	unsigned int		irq;
 	unsigned long		hwirq;
 	unsigned int		node;
@@ -705,11 +707,13 @@
  *				irq chips which need to call irq_set_wake() on
  *				the parent irq. Usually GPIO implementations
  * @IRQ_GC_MASK_CACHE_PER_TYPE:	Mask cache is chip type private
+ * @IRQ_GC_NO_MASK:		Do not calculate irq_data->mask
  */
 enum irq_gc_flags {
 	IRQ_GC_INIT_MASK_CACHE		= 1 << 0,
 	IRQ_GC_INIT_NESTED_LOCK		= 1 << 1,
 	IRQ_GC_MASK_CACHE_PER_TYPE	= 1 << 2,
+	IRQ_GC_NO_MASK			= 1 << 3,
 };
 
 /* Generic chip callback functions */