powerpc/eeh_cache: Don't use pci_dn when inserting new ranges

At the point where we start inserting ranges into the EEH address cache the
binding between pci_dev and eeh_dev has already been set up. Instead of
consulting the pci_dn tree we can retrieve the eeh_dev directly using
pci_dev_to_eeh_dev().
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Tested-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190715085612.8802-2-oohall@gmail.com

arch/powerpc/kernel/eeh_cache.c

@@ -159,18 +159,10 @@ eeh_addr_cache_insert(struct pci_dev *dev, resource_size_t alo,
 
 static void __eeh_addr_cache_insert_dev(struct pci_dev *dev)
 {
-	struct pci_dn *pdn;
 	struct eeh_dev *edev;
 	int i;
 
-	pdn = pci_get_pdn_by_devfn(dev->bus, dev->devfn);
-	if (!pdn) {
-		pr_warn("PCI: no pci dn found for dev=%s\n",
-			pci_name(dev));
-		return;
-	}
-
-	edev = pdn_to_eeh_dev(pdn);
+	edev = pci_dev_to_eeh_dev(dev);
 	if (!edev) {
 		pr_warn("PCI: no EEH dev found for %s\n",
 			pci_name(dev));