rapidio: add udev notification

Add RapidIO-specific modalias generation to enable udev notifications
about RapidIO-specific events.

The RapidIO modalias string format is shown below:

"rapidio:vNNNNdNNNNavNNNNadNNNN"

Where:
v  - Device Vendor ID (16 bit),
d  - Device ID (16 bit),
av - Assembly Vendor ID (16 bit),
ad - Assembly ID (16 bit),

as they are reported in corresponding Capability Registers (CARs)
of each RapidIO device.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Andre van Herk <andre.van.herk@Prodrive.nl>
Cc: Micha Nelissen <micha.nelissen@Prodrive.nl>
Cc: Stef van Os <stef.van.os@Prodrive.nl>
Cc: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rapidio/rio-driver.c b/drivers/rapidio/rio-driver.c
index a0c8755..3e9b6a7 100644
--- a/drivers/rapidio/rio-driver.c
+++ b/drivers/rapidio/rio-driver.c
@@ -199,6 +199,23 @@
       out:return 0;
 }
 
+static int rio_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct rio_dev *rdev;
+
+	if (!dev)
+		return -ENODEV;
+
+	rdev = to_rio_dev(dev);
+	if (!rdev)
+		return -ENODEV;
+
+	if (add_uevent_var(env, "MODALIAS=rapidio:v%04Xd%04Xav%04Xad%04X",
+			   rdev->vid, rdev->did, rdev->asm_vid, rdev->asm_did))
+		return -ENOMEM;
+	return 0;
+}
+
 struct device rio_bus = {
 	.init_name = "rapidio",
 };
@@ -210,6 +227,7 @@
 	.bus_attrs = rio_bus_attrs,
 	.probe = rio_device_probe,
 	.remove = rio_device_remove,
+	.uevent	= rio_uevent,
 };
 
 /**