usb_serial: API all change

USB serial likes to use port->tty back pointers for the real work it does and
to do so without any actual locking. Unfortunately when you consider hangup
events, hangup/parallel reopen or even worse hangup followed by parallel close
events the tty->port and port->tty pointers are not guaranteed to be the same
as port->tty is the active tty while tty->port is the port the tty may or
may not still be attached to.

So rework the entire API to pass the tty struct. For console cases we need
to pass both for now. This shows up multiple drivers that immediately crash
with USB console some of which have been fixed in the process.

Longer term we need a proper tty as console abstraction

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 20 insertions, 46 deletions

diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c
index 5fc20122145..373a3c7ea77 100644
--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -35,17 +35,15 @@
 #define DRIVER_DESC "USB HandSpring Visor / Palm OS driver"
 
 /* function prototypes for a handspring visor */
-static int  visor_open		(struct usb_serial_port *port, struct file *filp);
-static void visor_close		(struct usb_serial_port *port, struct file *filp);
-static int  visor_write		(struct usb_serial_port *port, const unsigned char *buf, int count);
-static int  visor_write_room		(struct usb_serial_port *port);
-static int  visor_chars_in_buffer	(struct usb_serial_port *port);
-static void visor_throttle	(struct usb_serial_port *port);
-static void visor_unthrottle	(struct usb_serial_port *port);
+static int  visor_open		(struct tty_struct *tty, struct usb_serial_port *port, struct file *filp);
+static void visor_close		(struct tty_struct *tty, struct usb_serial_port *port, struct file *filp);
+static int  visor_write		(struct tty_struct *tty, struct usb_serial_port *port, const unsigned char *buf, int count);
+static int  visor_write_room	(struct tty_struct *tty);
+static void visor_throttle	(struct tty_struct *tty);
+static void visor_unthrottle	(struct tty_struct *tty);
 static int  visor_probe		(struct usb_serial *serial, const struct usb_device_id *id);
 static int  visor_calc_num_ports(struct usb_serial *serial);
 static void visor_shutdown	(struct usb_serial *serial);
-static int  visor_ioctl		(struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg);
 static void visor_write_bulk_callback	(struct urb *urb);
 static void visor_read_bulk_callback	(struct urb *urb);
 static void visor_read_int_callback	(struct urb *urb);
@@ -198,10 +196,8 @@ static struct usb_serial_driver handspring_device = {
 	.probe =		visor_probe,
 	.calc_num_ports =	visor_calc_num_ports,
 	.shutdown =		visor_shutdown,
-	.ioctl =		visor_ioctl,
 	.write =		visor_write,
 	.write_room =		visor_write_room,
-	.chars_in_buffer =	visor_chars_in_buffer,
 	.write_bulk_callback =	visor_write_bulk_callback,
 	.read_bulk_callback =	visor_read_bulk_callback,
 	.read_int_callback =	visor_read_int_callback,
@@ -225,10 +221,8 @@ static struct usb_serial_driver clie_5_device = {
 	.probe =		visor_probe,
 	.calc_num_ports =	visor_calc_num_ports,
 	.shutdown =		visor_shutdown,
-	.ioctl =		visor_ioctl,
 	.write =		visor_write,
 	.write_room =		visor_write_room,
-	.chars_in_buffer =	visor_chars_in_buffer,
 	.write_bulk_callback =	visor_write_bulk_callback,
 	.read_bulk_callback =	visor_read_bulk_callback,
 	.read_int_callback =	visor_read_int_callback,
@@ -249,10 +243,8 @@ static struct usb_serial_driver clie_3_5_device = {
 	.throttle =		visor_throttle,
 	.unthrottle =		visor_unthrottle,
 	.attach =		clie_3_5_startup,
-	.ioctl =		visor_ioctl,
 	.write =		visor_write,
 	.write_room =		visor_write_room,
-	.chars_in_buffer =	visor_chars_in_buffer,
 	.write_bulk_callback =	visor_write_bulk_callback,
 	.read_bulk_callback =	visor_read_bulk_callback,
 };
@@ -274,7 +266,7 @@ static int stats;
 /******************************************************************************
  * Handspring Visor specific driver functions
  ******************************************************************************/
-static int visor_open (struct usb_serial_port *port, struct file *filp)
+static int visor_open (struct tty_struct *tty, struct usb_serial_port *port, struct file *filp)
 {
 	struct usb_serial *serial = port->serial;
 	struct visor_private *priv = usb_get_serial_port_data(port);
@@ -300,8 +292,8 @@ static int visor_open (struct usb_serial_port *port, struct file *filp)
 	 * through, otherwise it is scheduled, and with high data rates (like
 	 * with OHCI) data can get lost.
 	 */
-	if (port->tty)
-		port->tty->low_latency = 1;
+	if (tty)
+		tty->low_latency = 1;
 
 	/* Start reading from the device */
 	usb_fill_bulk_urb (port->read_urb, serial->dev,
@@ -329,7 +321,8 @@ exit:
 }
 
 
-static void visor_close (struct usb_serial_port *port, struct file * filp)
+static void visor_close(struct tty_struct *tty,
+			struct usb_serial_port *port, struct file * filp)
 {
 	struct visor_private *priv = usb_get_serial_port_data(port);
 	unsigned char *transfer_buffer;
@@ -361,7 +354,8 @@ static void visor_close (struct usb_serial_port *port, struct file * filp)
 }
 
 
-static int visor_write (struct usb_serial_port *port, const unsigned char *buf, int count)
+static int visor_write(struct tty_struct *tty, struct usb_serial_port *port,
+					const unsigned char *buf, int count)
 {
 	struct visor_private *priv = usb_get_serial_port_data(port);
 	struct usb_serial *serial = port->serial;
@@ -435,8 +429,9 @@ error_no_buffer:
 }
 
 
-static int visor_write_room (struct usb_serial_port *port)
+static int visor_write_room (struct tty_struct *tty)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct visor_private *priv = usb_get_serial_port_data(port);
 	unsigned long flags;
 
@@ -460,22 +455,6 @@ static int visor_write_room (struct usb_serial_port *port)
 }
 
 
-static int visor_chars_in_buffer (struct usb_serial_port *port)
-{
-	dbg("%s - port %d", __func__, port->number);
-
-	/* 
-	 * We can't really account for how much data we
-	 * have sent out, but hasn't made it through to the
-	 * device, so just tell the tty layer that everything
-	 * is flushed.
-	 *
-	 * FIXME: Should walk outstanding_urbs
-	 */
-	return 0;
-}
-
-
 static void visor_write_bulk_callback (struct urb *urb)
 {
 	struct usb_serial_port *port = urb->context;
@@ -520,7 +499,7 @@ static void visor_read_bulk_callback (struct urb *urb)
 
 	usb_serial_debug_data(debug, &port->dev, __func__, urb->actual_length, data);
 
-	tty = port->tty;
+	tty = port->port.tty;
 	if (tty && urb->actual_length) {
 		available_room = tty_buffer_request_room(tty, urb->actual_length);
 		if (available_room) {
@@ -591,8 +570,9 @@ exit:
 			__func__, result);
 }
 
-static void visor_throttle (struct usb_serial_port *port)
+static void visor_throttle (struct tty_struct *tty)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct visor_private *priv = usb_get_serial_port_data(port);
 	unsigned long flags;
 
@@ -603,8 +583,9 @@ static void visor_throttle (struct usb_serial_port *port)
 }
 
 
-static void visor_unthrottle (struct usb_serial_port *port)
+static void visor_unthrottle (struct tty_struct *tty)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct visor_private *priv = usb_get_serial_port_data(port);
 	unsigned long flags;
 	int result;
@@ -922,13 +903,6 @@ static void visor_shutdown (struct usb_serial *serial)
 	}
 }
 
-static int visor_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
-{
-	dbg("%s - port %d, cmd 0x%.4x", __func__, port->number, cmd);
-
-	return -ENOIOCTLCMD;
-}
-
 static int __init visor_init (void)
 {
 	int i, retval;