[PATCH] htirq: refactor so we only have one function that writes to the chip

This refactoring actually optimizes the code a little by caching the value
that we think the device is programmed with instead of reading it back from
the hardware.  Which simplifies the code a little and should speed things up a
bit.

This patch introduces the concept of a ht_irq_msg and modifies the
architecture read/write routines to update this code.

There is a minor consistency fix here as well as x86_64 forgot to initialize
the htirq as masked.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Andi Kleen <ak@suse.de>
Acked-by: Bryan O'Sullivan <bos@pathscale.com>
Cc: <olson@pathscale.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/htirq.h b/include/linux/htirq.h
index 1f15ce2..108f0d9 100644
--- a/include/linux/htirq.h
+++ b/include/linux/htirq.h
@@ -1,11 +1,14 @@
 #ifndef LINUX_HTIRQ_H
 #define LINUX_HTIRQ_H
 
+struct ht_irq_msg {
+	u32	address_lo;	/* low 32 bits of the ht irq message */
+	u32	address_hi;	/* high 32 bits of the it irq message */
+};
+
 /* Helper functions.. */
-void write_ht_irq_low(unsigned int irq, u32 data);
-void write_ht_irq_high(unsigned int irq, u32 data);
-u32  read_ht_irq_low(unsigned int irq);
-u32  read_ht_irq_high(unsigned int irq);
+void fetch_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg);
+void write_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg);
 void mask_ht_irq(unsigned int irq);
 void unmask_ht_irq(unsigned int irq);