quoted

+
+	/* Check that nothing else has already setup a handler */
+	if (pm_power_off) {
+		lookup_symbol_name((ulong)pm_power_off, symname);
+		dev_err(&pdev->dev,
+			"pm_power_off already claimed %p %s",
+			pm_power_off, symname);
+		return -EBUSY;
+	}
+	pm_power_off = linkstation_reset;

That seems a bit complicated, why not just assume that there will be
either this driver used, or not at all?

That is probably my fault. This is a copy from code i wrote many years
ago for the QNAP. I guess at the time i was battling with two
different pm_power_off handlers, so put in this code.

Also, you are supposed to register a reboot notifier to which you can
pass private context:

At the time i wrote the QNAP code, this did not exist. So maybe my
code is no longer a good example to copy.

	 Andrew