rapidio: add global inbound port write interfaces

Add new Port Write handler registration interfaces that attach PW
handlers to local mport device objects.  This is different from old
interface that attaches PW callback to individual RapidIO device.  The
new interfaces are intended for use for common event handling (e.g.
hot-plug notifications) while the old interface is available for
individual device drivers.

This patch is based on patch proposed by Andre van Herk but preserves
existing per-device interface and adds lock protection for list
handling.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/rio_drv.h b/include/linux/rio_drv.h
index 9fb2bcd..5dff9a4 100644
--- a/include/linux/rio_drv.h
+++ b/include/linux/rio_drv.h
@@ -374,7 +374,14 @@
 extern int rio_request_inb_pwrite(struct rio_dev *,
 			int (*)(struct rio_dev *, union rio_pw_msg*, int));
 extern int rio_release_inb_pwrite(struct rio_dev *);
-extern int rio_inb_pwrite_handler(union rio_pw_msg *pw_msg);
+extern int rio_add_mport_pw_handler(struct rio_mport *mport, void *dev_id,
+			int (*pwcback)(struct rio_mport *mport, void *dev_id,
+			union rio_pw_msg *msg, int step));
+extern int rio_del_mport_pw_handler(struct rio_mport *mport, void *dev_id,
+			int (*pwcback)(struct rio_mport *mport, void *dev_id,
+			union rio_pw_msg *msg, int step));
+extern int rio_inb_pwrite_handler(struct rio_mport *mport,
+				  union rio_pw_msg *pw_msg);
 extern void rio_pw_enable(struct rio_mport *mport, int enable);
 
 /* LDM support */