irqdomain: Remove powerpc dependency from debugfs file

The debugfs code is really generic for all platforms.  This patch removes the
powerpc-specific directory reference and makes it available to all
architectures.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

arch/powerpc/Kconfig.debug

@@ -114,16 +114,6 @@ config DEBUGGER
 	depends on KGDB || XMON
 	default y
 
-config VIRQ_DEBUG
-	bool "Expose hardware/virtual IRQ mapping via debugfs"
-	depends on DEBUG_FS
-	help
-	  This option will show the mapping relationship between hardware irq
-	  numbers and virtual irq numbers. The mapping is exposed via debugfs
-	  in the file powerpc/virq_mapping.
-
-	  If you don't know what this means you don't need it.
-
 config BDI_SWITCH
 	bool "Include BDI-2000 user context switcher"
 	depends on DEBUG_KERNEL && PPC32

kernel/irq/Kconfig

@@ -56,6 +56,16 @@ config GENERIC_IRQ_CHIP
 config IRQ_DOMAIN
 	bool
 
+config IRQ_DOMAIN_DEBUG
+	bool "Expose hardware/virtual IRQ mapping via debugfs"
+	depends on IRQ_DOMAIN && DEBUG_FS
+	help
+	  This option will show the mapping relationship between hardware irq
+	  numbers and Linux irq numbers. The mapping is exposed via debugfs
+	  in the file "virq_mapping".
+
+	  If you don't know what this means you don't need it.
+
 # Support forced irq threading
 config IRQ_FORCED_THREADING
        bool

kernel/irq/irqdomain.c

@@ -632,7 +632,7 @@ unsigned int irq_linear_revmap(struct irq_domain *domain,
 	return revmap[hwirq];
 }
 
-#ifdef CONFIG_VIRQ_DEBUG
+#ifdef CONFIG_IRQ_DOMAIN_DEBUG
 static int virq_debug_show(struct seq_file *m, void *private)
 {
 	unsigned long flags;
@@ -668,7 +668,7 @@ static int virq_debug_show(struct seq_file *m, void *private)
 			data = irq_desc_get_chip_data(desc);
 			seq_printf(m, "0x%16p  ", data);
 
-			if (desc->irq_data.domain->of_node)
+			if (desc->irq_data.domain && desc->irq_data.domain->of_node)
 				p = desc->irq_data.domain->of_node->full_name;
 			else
 				p = none;
@@ -695,14 +695,14 @@ static const struct file_operations virq_debug_fops = {
 
 static int __init irq_debugfs_init(void)
 {
-	if (debugfs_create_file("virq_mapping", S_IRUGO, powerpc_debugfs_root,
+	if (debugfs_create_file("irq_domain_mapping", S_IRUGO, NULL,
 				 NULL, &virq_debug_fops) == NULL)
 		return -ENOMEM;
 
 	return 0;
 }
 __initcall(irq_debugfs_init);
-#endif /* CONFIG_VIRQ_DEBUG */
+#endif /* CONFIG_IRQ_DOMAIN_DEBUG */
 
 int irq_domain_simple_map(struct irq_domain *d, unsigned int irq,
 			  irq_hw_number_t hwirq)