TTY: hvcs, add tty install

This has two outcomes:
* we give the TTY layer a tty_port
* we do not find the info structure every time open is called on that
  tty

>From now on, we only increase the reference count in ->install (and
decrease in ->cleanup).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: linuxppc-dev@lists.ozlabs.org
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c
index 6f5c3be..cab5c7a 100644 (file)
--- a/drivers/tty/hvc/hvcs.c
+++ b/drivers/tty/hvc/hvcs.c
@@ -1102,11 +1102,7 @@ static struct hvcs_struct *hvcs_get_by_index(int index)
        return NULL;
 }
 
-/*
- * This is invoked via the tty_open interface when a user app connects to the
- * /dev node.
- */
-static int hvcs_open(struct tty_struct *tty, struct file *filp)
+static int hvcs_install(struct tty_driver *driver, struct tty_struct *tty)
 {
        struct hvcs_struct *hvcsd;
        struct vio_dev *vdev;
@@ -1114,9 +1110,6 @@ static int hvcs_open(struct tty_struct *tty, struct file *filp)
        unsigned int irq;
        int retval;
 
-       if (tty->driver_data)
-               goto fast_open;
-
        /*
         * Is there a vty-server that shares the same index?
         * This function increments the kref index.
@@ -1139,7 +1132,7 @@ static int hvcs_open(struct tty_struct *tty, struct file *filp)
                }
        }
 
-       hvcsd->port.count = 1;
+       hvcsd->port.count = 0;
        hvcsd->port.tty = tty;
        tty->driver_data = hvcsd;
 
@@ -1166,28 +1159,42 @@ static int hvcs_open(struct tty_struct *tty, struct file *filp)
                goto err_put;
        }
 
-       goto open_success;
+       retval = tty_port_install(&hvcsd->port, driver, tty);
+       if (retval)
+               goto err_irq;
 
-fast_open:
-       hvcsd = tty->driver_data;
+       return 0;
+err_irq:
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       vio_disable_interrupts(hvcsd->vdev);
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       free_irq(irq, hvcsd);
+err_put:
+       tty_port_put(&hvcsd->port);
+
+       return retval;
+}
+
+/*
+ * This is invoked via the tty_open interface when a user app connects to the
+ * /dev node.
+ */
+static int hvcs_open(struct tty_struct *tty, struct file *filp)
+{
+       struct hvcs_struct *hvcsd = tty->driver_data;
+       unsigned long flags;
 
        spin_lock_irqsave(&hvcsd->lock, flags);
-       tty_port_get(&hvcsd->port);
        hvcsd->port.count++;
        hvcsd->todo_mask |= HVCS_SCHED_READ;
        spin_unlock_irqrestore(&hvcsd->lock, flags);
 
-open_success:
        hvcs_kick();
 
        printk(KERN_INFO "HVCS: vty-server@%X connection opened.\n",
                hvcsd->vdev->unit_address );
 
        return 0;
-err_put:
-       tty_port_put(&hvcsd->port);
-
-       return retval;
 }
 
 static void hvcs_close(struct tty_struct *tty, struct file *filp)
@@ -1238,7 +1245,6 @@ static void hvcs_close(struct tty_struct *tty, struct file *filp)
                tty->driver_data = NULL;
 
                free_irq(irq, hvcsd);
-               tty_port_put(&hvcsd->port);
                return;
        } else if (hvcsd->port.count < 0) {
                printk(KERN_ERR "HVCS: vty-server@%X open_count: %d"
@@ -1247,6 +1253,12 @@ static void hvcs_close(struct tty_struct *tty, struct file *filp)
        }
 
        spin_unlock_irqrestore(&hvcsd->lock, flags);
+}
+
+static void hvcs_cleanup(struct tty_struct * tty)
+{
+       struct hvcs_struct *hvcsd = tty->driver_data;
+
        tty_port_put(&hvcsd->port);
 }
 
@@ -1433,8 +1445,10 @@ static int hvcs_chars_in_buffer(struct tty_struct *tty)
 }
 
 static const struct tty_operations hvcs_ops = {
+       .install = hvcs_install,
        .open = hvcs_open,
        .close = hvcs_close,
+       .cleanup = hvcs_cleanup,
        .hangup = hvcs_hangup,
        .write = hvcs_write,
        .write_room = hvcs_write_room,