microblaze: intc: Registering interrupt should return value

Return value to find out if un/registration was succesful.

Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/arch/microblaze/cpu/interrupts.c b/arch/microblaze/cpu/interrupts.c
index ee67082..08f6bad 100644
--- a/arch/microblaze/cpu/interrupts.c
+++ b/arch/microblaze/cpu/interrupts.c
@@ -91,14 +91,13 @@
 #endif
 }
 
-/* adding new handler for interrupt */
-void install_interrupt_handler (int irq, interrupt_handler_t * hdlr, void *arg)
+int install_interrupt_handler(int irq, interrupt_handler_t *hdlr, void *arg)
 {
 	struct irq_action *act;
 	/* irq out of range */
 	if ((irq < 0) || (irq > irq_no)) {
 		puts ("IRQ out of range\n");
-		return;
+		return -1;
 	}
 	act = &vecs[irq];
 	if (hdlr) {		/* enable */
@@ -106,11 +105,14 @@
 		act->arg = arg;
 		act->count = 0;
 		enable_one_interrupt (irq);
-	} else {		/* disable */
-		act->handler = (interrupt_handler_t *) def_hdlr;
-		act->arg = (void *)irq;
-		disable_one_interrupt (irq);
+		return 0;
 	}
+
+	/* Disable */
+	act->handler = (interrupt_handler_t *) def_hdlr;
+	act->arg = (void *)irq;
+	disable_one_interrupt(irq);
+	return 1;
 }
 
 /* initialization interrupt controller - hardware */
diff --git a/arch/microblaze/include/asm/microblaze_intc.h b/arch/microblaze/include/asm/microblaze_intc.h
index 6142b9c..e9640f5 100644
--- a/arch/microblaze/include/asm/microblaze_intc.h
+++ b/arch/microblaze/include/asm/microblaze_intc.h
@@ -39,7 +39,16 @@
 	int count; /* number of interrupt */
 };
 
-void install_interrupt_handler (int irq, interrupt_handler_t * hdlr,
+/**
+ * Register and unregister interrupt handler rutines
+ *
+ * @param irq	IRQ number
+ * @param hdlr	Interrupt handler rutine
+ * @param arg	Pointer to argument which is passed to int. handler rutine
+ * @return	0 if registration pass, 1 if unregistration pass,
+ *		or an error code < 0 otherwise
+ */
+int install_interrupt_handler(int irq, interrupt_handler_t *hdlr,
 				       void *arg);
 
 int interrupts_init(void);