devicetree: add helper inline for retrieving a node's full name

The pattern (np ? np->full_name : "<none>") is rather common in the
kernel, but can also make for quite long lines.  This patch adds a new
inline function, of_node_full_name() so that the test for a valid node
pointer doesn't need to be open coded at all call sites.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
index ed22bfc..ca8f6e7 100644
--- a/arch/microblaze/pci/pci-common.c
+++ b/arch/microblaze/pci/pci-common.c
@@ -249,8 +249,7 @@
 	} else {
 		pr_debug(" Got one, spec %d cells (0x%08x 0x%08x...) on %s\n",
 			 oirq.size, oirq.specifier[0], oirq.specifier[1],
-			 oirq.controller ? oirq.controller->full_name :
-			 "<default>");
+			 of_node_full_name(oirq.controller));
 
 		virq = irq_create_of_mapping(oirq.controller, oirq.specifier,
 					     oirq.size);
@@ -1493,8 +1492,7 @@
 	struct pci_bus *bus;
 	struct device_node *node = hose->dn;
 
-	pr_debug("PCI: Scanning PHB %s\n",
-		 node ? node->full_name : "<NO NAME>");
+	pr_debug("PCI: Scanning PHB %s\n", of_node_full_name(node));
 
 	pcibios_setup_phb_resources(hose, &resources);
 
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index 8e78e93..886c254 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -248,8 +248,7 @@
 	} else {
 		pr_debug(" Got one, spec %d cells (0x%08x 0x%08x...) on %s\n",
 			 oirq.size, oirq.specifier[0], oirq.specifier[1],
-			 oirq.controller ? oirq.controller->full_name :
-			 "<default>");
+			 of_node_full_name(oirq.controller));
 
 		virq = irq_create_of_mapping(oirq.controller, oirq.specifier,
 					     oirq.size);
@@ -1628,8 +1627,7 @@
 	struct device_node *node = hose->dn;
 	int mode;
 
-	pr_debug("PCI: Scanning PHB %s\n",
-		 node ? node->full_name : "<NO NAME>");
+	pr_debug("PCI: Scanning PHB %s\n", of_node_full_name(node));
 
 	/* Get some IO space for the new PHB */
 	pcibios_setup_phb_io_space(hose);
diff --git a/arch/powerpc/kernel/vio.c b/arch/powerpc/kernel/vio.c
index cb87301..63f72ed 100644
--- a/arch/powerpc/kernel/vio.c
+++ b/arch/powerpc/kernel/vio.c
@@ -1296,8 +1296,7 @@
 	struct iommu_table *tbl = get_iommu_table_base(dev);
 
 	if (tbl)
-		iommu_free_table(tbl, dev->of_node ?
-			dev->of_node->full_name : dev_name(dev));
+		iommu_free_table(tbl, of_node_full_name(dev->of_node));
 	of_node_put(dev->of_node);
 	kfree(to_vio_dev(dev));
 }
@@ -1509,7 +1508,7 @@
 {
 	struct device_node *of_node = dev->of_node;
 
-	return sprintf(buf, "%s\n", of_node ? of_node->full_name : "none");
+	return sprintf(buf, "%s\n", of_node_full_name(of_node));
 }
 
 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
diff --git a/arch/powerpc/platforms/cell/iommu.c b/arch/powerpc/platforms/cell/iommu.c
index b9f509a..b673200 100644
--- a/arch/powerpc/platforms/cell/iommu.c
+++ b/arch/powerpc/platforms/cell/iommu.c
@@ -552,8 +552,7 @@
 	iommu = cell_iommu_for_node(dev_to_node(dev));
 	if (iommu == NULL || list_empty(&iommu->windows)) {
 		printk(KERN_ERR "iommu: missing iommu for %s (node %d)\n",
-		       dev->of_node ? dev->of_node->full_name : "?",
-		       dev_to_node(dev));
+		       of_node_full_name(dev->of_node), dev_to_node(dev));
 		return NULL;
 	}
 	window = list_entry(iommu->windows.next, struct iommu_window, list);
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index 2d311c0..6b58a39 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -1051,7 +1051,7 @@
 	if (!pdn || !PCI_DN(pdn)) {
 		printk(KERN_WARNING "pci_dma_dev_setup_pSeriesLP: "
 		       "no DMA window found for pci dev=%s dn=%s\n",
-				 pci_name(dev), dn? dn->full_name : "<null>");
+				 pci_name(dev), of_node_full_name(dn));
 		return;
 	}
 	pr_debug("  parent is %s\n", pdn->full_name);
diff --git a/arch/sparc/kernel/of_device_64.c b/arch/sparc/kernel/of_device_64.c
index 7a3be6f..7bbdc26 100644
--- a/arch/sparc/kernel/of_device_64.c
+++ b/arch/sparc/kernel/of_device_64.c
@@ -580,7 +580,7 @@
 				printk("%s: Apply [%s:%x] imap --> [%s:%x]\n",
 				       op->dev.of_node->full_name,
 				       pp->full_name, this_orig_irq,
-				       (iret ? iret->full_name : "NULL"), irq);
+				       of_node_full_name(iret), irq);
 
 			if (!iret)
 				break;
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 8575795..9ec0a2f 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1173,7 +1173,7 @@
 	ap->stem[stem_len] = 0;
 	list_add_tail(&ap->link, &aliases_lookup);
 	pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n",
-		 ap->alias, ap->stem, ap->id, np ? np->full_name : NULL);
+		 ap->alias, ap->stem, ap->id, of_node_full_name(np));
 }
 
 /**
diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index 9cf0060..ff8ab7b 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -255,7 +255,7 @@
 
 	skiplevel:
 		/* Iterate again with new parent */
-		pr_debug(" -> new parent: %s\n", newpar ? newpar->full_name : "<>");
+		pr_debug(" -> new parent: %s\n", of_node_full_name(newpar));
 		of_node_put(ipar);
 		ipar = newpar;
 		newpar = NULL;
diff --git a/include/linux/of.h b/include/linux/of.h
index 2ec1083..1012377 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -163,6 +163,11 @@
 #define of_node_to_nid of_node_to_nid
 #endif
 
+static inline const char* of_node_full_name(struct device_node *np)
+{
+	return np ? np->full_name : "<no-node>";
+}
+
 extern struct device_node *of_find_node_by_name(struct device_node *from,
 	const char *name);
 #define for_each_node_by_name(dn, name) \
@@ -303,6 +308,11 @@
 
 #else /* CONFIG_OF */
 
+static inline const char* of_node_full_name(struct device_node *np)
+{
+	return "<no-node>";
+}
+
 static inline bool of_have_populated_dt(void)
 {
 	return false;
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 41c1564..38c5eb8 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -448,7 +448,7 @@
 	}
 
 	pr_debug("irq %lu on domain %s mapped to virtual irq %u\n",
-		hwirq, domain->of_node ? domain->of_node->full_name : "null", virq);
+		hwirq, of_node_full_name(domain->of_node), virq);
 
 	return virq;
 }
@@ -477,7 +477,7 @@
 			return intspec[0];
 #endif
 		pr_warning("no irq domain found for %s !\n",
-			   controller->full_name);
+			   of_node_full_name(controller));
 		return 0;
 	}
 
@@ -725,8 +725,8 @@
 			data = irq_desc_get_chip_data(desc);
 			seq_printf(m, data ? "0x%p  " : "  %p  ", data);
 
-			if (desc->irq_data.domain && desc->irq_data.domain->of_node)
-				p = desc->irq_data.domain->of_node->full_name;
+			if (desc->irq_data.domain)
+				p = of_node_full_name(desc->irq_data.domain->of_node);
 			else
 				p = none;
 			seq_printf(m, "%s\n", p);