Patch from Ben Dooks
Check that the device we are looking at is really
a platform device before trying to cast it to one
to find out the platform bus number.
Thanks to RMK for pointing this out.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
        struct clk *clk = ERR_PTR(-ENOENT);
        int idno;
 
-       idno = (dev == NULL) ? -1 : to_platform_device(dev)->id;
+       if (dev == NULL || dev->bus != &platform_bus_type)
+               idno = -1;
+       else
+               idno = to_platform_device(dev)->id;
 
        down(&clocks_sem);