USB: EHCI: log a warning if ehci-hcd is not loaded first

This patch (as1139) adds a warning to the system log whenever ehci-hcd
is loaded after ohci-hcd or uhci-hcd.  Nowadays most distributions are
pretty good about not doing this; maybe the warning will help convince
anyone still doing it wrong.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>  [2.6.27]
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/host/uhci-hcd.c b/drivers/usb/host/uhci-hcd.c
index 2dddb25..cf5e4cf 100644
--- a/drivers/usb/host/uhci-hcd.c
+++ b/drivers/usb/host/uhci-hcd.c
@@ -955,6 +955,7 @@
 
 	printk(KERN_INFO "uhci_hcd: " DRIVER_DESC "%s\n",
 			ignore_oc ? ", overcurrent ignored" : "");
+	set_bit(USB_UHCI_LOADED, &usb_hcds_loaded);
 
 	if (DEBUG_CONFIGURED) {
 		errbuf = kmalloc(ERRBUF_LEN, GFP_KERNEL);
@@ -987,6 +988,7 @@
 
 errbuf_failed:
 
+	clear_bit(USB_UHCI_LOADED, &usb_hcds_loaded);
 	return retval;
 }
 
@@ -996,6 +998,7 @@
 	kmem_cache_destroy(uhci_up_cachep);
 	debugfs_remove(uhci_debugfs_root);
 	kfree(errbuf);
+	clear_bit(USB_UHCI_LOADED, &usb_hcds_loaded);
 }
 
 module_init(uhci_hcd_init);