powerpc/pci: Export pci_traverse_device_nodes()

This renames traverse_pci_devices() to pci_traverse_device_nodes().
The function traverses all subordinate device nodes of the specified
one. Also, below cleanup applied to the function. No logical changes
introduced.

   * Rename "pre" to "fn".
   * Avoid assignment in if condition reported from checkpatch.pl.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/ppc-pci.h

@@ -33,9 +33,9 @@ extern struct pci_dev *isa_bridge_pcidev;	/* may be NULL if no ISA bus */
 struct device_node;
 struct pci_dn;
 
-typedef void *(*traverse_func)(struct device_node *me, void *data);
-void *traverse_pci_devices(struct device_node *start, traverse_func pre,
-		void *data);
+void *pci_traverse_device_nodes(struct device_node *start,
+				void *(*fn)(struct device_node *, void *),
+				void *data);
 void *traverse_pci_dn(struct pci_dn *root,
 		      void *(*fn)(struct pci_dn *, void *),
 		      void *data);

arch/powerpc/kernel/pci_dn.c

@@ -372,8 +372,9 @@ EXPORT_SYMBOL_GPL(pci_remove_device_node_info);
  * one of these nodes we also assume its siblings are non-pci for
  * performance.
  */
-void *traverse_pci_devices(struct device_node *start, traverse_func pre,
-		void *data)
+void *pci_traverse_device_nodes(struct device_node *start,
+				void *(*fn)(struct device_node *, void *),
+				void *data)
 {
 	struct device_node *dn, *nextdn;
 	void *ret;
@@ -388,8 +389,11 @@ void *traverse_pci_devices(struct device_node *start, traverse_func pre,
 		if (classp)
 			class = of_read_number(classp, 1);
 
-		if (pre && ((ret = pre(dn, data)) != NULL))
-			return ret;
+		if (fn) {
+			ret = fn(dn, data);
+			if (ret)
+				return ret;
+		}
 
 		/* If we are a PCI bridge, go down */
 		if (dn->child && ((class >> 8) == PCI_CLASS_BRIDGE_PCI ||
@@ -411,6 +415,7 @@ void *traverse_pci_devices(struct device_node *start, traverse_func pre,
 	}
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(pci_traverse_device_nodes);
 
 static struct pci_dn *pci_dn_next_one(struct pci_dn *root,
 				      struct pci_dn *pdn)
@@ -487,7 +492,7 @@ void pci_devs_phb_init_dynamic(struct pci_controller *phb)
 	}
 
 	/* Update dn->phb ptrs for new phb and children devices */
-	traverse_pci_devices(dn, add_pdn, phb);
+	pci_traverse_device_nodes(dn, add_pdn, phb);
 }
 
 /** 

arch/powerpc/platforms/pseries/msi.c

@@ -305,7 +305,7 @@ static int msi_quota_for_device(struct pci_dev *dev, int request)
 	memset(&counts, 0, sizeof(struct msi_counts));
 
 	/* Work out how many devices we have below this PE */
-	traverse_pci_devices(pe_dn, count_non_bridge_devices, &counts);
+	pci_traverse_device_nodes(pe_dn, count_non_bridge_devices, &counts);
 
 	if (counts.num_devices == 0) {
 		pr_err("rtas_msi: found 0 devices under PE for %s\n",
@@ -320,7 +320,7 @@ static int msi_quota_for_device(struct pci_dev *dev, int request)
 	/* else, we have some more calculating to do */
 	counts.requestor = pci_device_to_OF_node(dev);
 	counts.request = request;
-	traverse_pci_devices(pe_dn, count_spare_msis, &counts);
+	pci_traverse_device_nodes(pe_dn, count_spare_msis, &counts);
 
 	/* If the quota isn't an integer multiple of the total, we can
 	 * use the remainder as spare MSIs for anyone that wants them. */