genirq: Return the IRQ name from free_irq()

This allows callers to get back at them instead of having to store it in
another variable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>

2 files changed, 11 insertions, 4 deletions

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 53144e78a369..a6fba4804672 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -155,7 +155,7 @@ extern int __must_check
 request_percpu_irq(unsigned int irq, irq_handler_t handler,
                    const char *devname, void __percpu *percpu_dev_id);
 
-extern void free_irq(unsigned int, void *);
+extern const void *free_irq(unsigned int, void *);
 extern void free_percpu_irq(unsigned int, void __percpu *);
 
 struct device;
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 391cb738b2db..e688e7e06772 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -1574,20 +1574,27 @@ EXPORT_SYMBOL_GPL(remove_irq);
  *      have completed.
  *
  *      This function must not be called from interrupt context.
+ *
+ *      Returns the devname argument passed to request_irq.
  */
-void free_irq(unsigned int irq, void *dev_id)
+const void *free_irq(unsigned int irq, void *dev_id)
 {
         struct irq_desc *desc = irq_to_desc(irq);
+        struct irqaction *action;
+        const char *devname;
 
         if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
-                return;
+                return NULL;
 
 #ifdef CONFIG_SMP
         if (WARN_ON(desc->affinity_notify))
                 desc->affinity_notify = NULL;
 #endif
 
-        kfree(__free_irq(irq, dev_id));
+        action = __free_irq(irq, dev_id);
+        devname = action->name;
+        kfree(action);
+        return devname;
 }
 EXPORT_SYMBOL(free_irq);