hvc_console: Add a hangup notifier for backends

I have added a hangup notifier that can be used by hvc console
backends to handle a tty hangup. The default irq hangup notifier
calls the notifier_del_irq() for compatibility.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/char/hvc_console.h b/drivers/char/hvc_console.h
index 9790201718ae..ec0e9bb0e5e6 100644
--- a/drivers/char/hvc_console.h
+++ b/drivers/char/hvc_console.h
@@ -65,9 +65,10 @@ struct hv_ops {
         int (*get_chars)(uint32_t vtermno, char *buf, int count);
         int (*put_chars)(uint32_t vtermno, const char *buf, int count);
 
-        /* Callbacks for notification. Called in open and close */
+        /* Callbacks for notification. Called in open, close and hangup */
         int (*notifier_add)(struct hvc_struct *hp, int irq);
         void (*notifier_del)(struct hvc_struct *hp, int irq);
+        void (*notifier_hangup)(struct hvc_struct *hp, int irq);
 };
 
 /* Register a vterm and a slot index for use as a console (console_init) */
@@ -86,6 +87,7 @@ void hvc_kick(void);
 /* default notifier for irq based notification */
 extern int notifier_add_irq(struct hvc_struct *hp, int data);
 extern void notifier_del_irq(struct hvc_struct *hp, int data);
+extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
 
 
 #if defined(CONFIG_XMON) && defined(CONFIG_SMP)