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, 29 insertions, 40 deletions

diff --git a/drivers/usb/serial/keyspan_pda.c b/drivers/usb/serial/keyspan_pda.c
index 60b3e22bd63..24a08ac2e4e 100644
--- a/drivers/usb/serial/keyspan_pda.c
+++ b/drivers/usb/serial/keyspan_pda.c
@@ -171,7 +171,7 @@ static void keyspan_pda_wakeup_write(struct work_struct *work)
 		container_of(work, struct keyspan_pda_private, wakeup_work);
 	struct usb_serial_port *port = priv->port;
 
-	tty_wakeup(port->tty);
+	tty_wakeup(port->port.tty);
 }
 
 static void keyspan_pda_request_unthrottle(struct work_struct *work)
@@ -203,7 +203,7 @@ static void keyspan_pda_request_unthrottle(struct work_struct *work)
 static void keyspan_pda_rx_interrupt (struct urb *urb)
 {
 	struct usb_serial_port *port = urb->context;
-       	struct tty_struct *tty = port->tty;
+       	struct tty_struct *tty = port->port.tty;
 	unsigned char *data = urb->transfer_buffer;
 	int i;
 	int retval;
@@ -266,7 +266,7 @@ exit:
 }
 
 
-static void keyspan_pda_rx_throttle (struct usb_serial_port *port)
+static void keyspan_pda_rx_throttle(struct tty_struct *tty)
 {
 	/* stop receiving characters. We just turn off the URB request, and
 	   let chars pile up in the device. If we're doing hardware
@@ -274,14 +274,15 @@ static void keyspan_pda_rx_throttle (struct usb_serial_port *port)
 	   fills up. If we're doing XON/XOFF, this would be a good time to
 	   send an XOFF, although it might make sense to foist that off
 	   upon the device too. */
-
+	struct usb_serial_port *port = tty->driver_data;
 	dbg("keyspan_pda_rx_throttle port %d", port->number);
 	usb_kill_urb(port->interrupt_in_urb);
 }
 
 
-static void keyspan_pda_rx_unthrottle (struct usb_serial_port *port)
+static void keyspan_pda_rx_unthrottle(struct tty_struct *tty)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	/* just restart the receive interrupt URB */
 	dbg("keyspan_pda_rx_unthrottle port %d", port->number);
 	port->interrupt_in_urb->dev = port->serial->dev;
@@ -330,8 +331,9 @@ static speed_t keyspan_pda_setbaud (struct usb_serial *serial, speed_t baud)
 }
 
 
-static void keyspan_pda_break_ctl (struct usb_serial_port *port, int break_state)
+static void keyspan_pda_break_ctl(struct tty_struct *tty, int break_state)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct usb_serial *serial = port->serial;
 	int value;
 	int result;
@@ -354,8 +356,8 @@ static void keyspan_pda_break_ctl (struct usb_serial_port *port, int break_state
 }
 
 
-static void keyspan_pda_set_termios (struct usb_serial_port *port, 
-				     struct ktermios *old_termios)
+static void keyspan_pda_set_termios(struct tty_struct *tty,
+		struct usb_serial_port *port, struct ktermios *old_termios)
 {
 	struct usb_serial *serial = port->serial;
 	speed_t speed;
@@ -380,7 +382,7 @@ static void keyspan_pda_set_termios (struct usb_serial_port *port,
 
 	   For now, just do baud. */
 
-	speed = tty_get_baud_rate(port->tty);
+	speed = tty_get_baud_rate(tty);
 	speed = keyspan_pda_setbaud(serial, speed);
 
 	if (speed == 0) {
@@ -390,8 +392,8 @@ static void keyspan_pda_set_termios (struct usb_serial_port *port,
 	}
 	/* Only speed can change so copy the old h/w parameters
 	   then encode the new speed */
-	tty_termios_copy_hw(port->tty->termios, old_termios);
-	tty_encode_baud_rate(port->tty, speed, speed);
+	tty_termios_copy_hw(tty->termios, old_termios);
+	tty_encode_baud_rate(tty, speed, speed);
 }
 
 
@@ -425,8 +427,9 @@ static int keyspan_pda_set_modem_info(struct usb_serial *serial,
 	return rc;
 }
 
-static int keyspan_pda_tiocmget(struct usb_serial_port *port, struct file *file)
+static int keyspan_pda_tiocmget(struct tty_struct *tty, struct file *file)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct usb_serial *serial = port->serial;
 	int rc;
 	unsigned char status;
@@ -445,9 +448,10 @@ static int keyspan_pda_tiocmget(struct usb_serial_port *port, struct file *file)
 	return value;
 }
 
-static int keyspan_pda_tiocmset(struct usb_serial_port *port, struct file *file,
+static int keyspan_pda_tiocmset(struct tty_struct *tty, struct file *file,
 				unsigned int set, unsigned int clear)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct usb_serial *serial = port->serial;
 	int rc;
 	unsigned char status;
@@ -469,23 +473,8 @@ static int keyspan_pda_tiocmset(struct usb_serial_port *port, struct file *file,
 	return rc;
 }
 
-static int keyspan_pda_ioctl(struct usb_serial_port *port, struct file *file,
-			     unsigned int cmd, unsigned long arg)
-{
-	switch (cmd) {
-	case TIOCMIWAIT:
-		/* wait for any of the 4 modem inputs (DCD,RI,DSR,CTS)*/
-		/* TODO */
-	case TIOCGICOUNT:
-		/* return count of modemline transitions */
-		return 0; /* TODO */
-	}
-	
-	return -ENOIOCTLCMD;
-}
-
-static int keyspan_pda_write(struct usb_serial_port *port, 
-			     const unsigned char *buf, int count)
+static int keyspan_pda_write(struct tty_struct *tty,
+	struct usb_serial_port *port, const unsigned char *buf, int count)
 {
 	struct usb_serial *serial = port->serial;
 	int request_unthrottle = 0;
@@ -607,22 +596,21 @@ static void keyspan_pda_write_bulk_callback (struct urb *urb)
 }
 
 
-static int keyspan_pda_write_room (struct usb_serial_port *port)
+static int keyspan_pda_write_room(struct tty_struct *tty)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct keyspan_pda_private *priv;
-
 	priv = usb_get_serial_port_data(port);
-
 	/* used by n_tty.c for processing of tabs and such. Giving it our
 	   conservative guess is probably good enough, but needs testing by
 	   running a console through the device. */
-
 	return (priv->tx_room);
 }
 
 
-static int keyspan_pda_chars_in_buffer (struct usb_serial_port *port)
+static int keyspan_pda_chars_in_buffer(struct tty_struct *tty)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct keyspan_pda_private *priv;
 	unsigned long flags;
 	int ret = 0;
@@ -640,7 +628,8 @@ static int keyspan_pda_chars_in_buffer (struct usb_serial_port *port)
 }
 
 
-static int keyspan_pda_open (struct usb_serial_port *port, struct file *filp)
+static int keyspan_pda_open(struct tty_struct *tty,
+			struct usb_serial_port *port, struct file *filp)
 {
 	struct usb_serial *serial = port->serial;
 	unsigned char room;
@@ -672,7 +661,7 @@ static int keyspan_pda_open (struct usb_serial_port *port, struct file *filp)
 
 	/* the normal serial device seems to always turn on DTR and RTS here,
 	   so do the same */
-	if (port->tty->termios->c_cflag & CBAUD)
+	if (tty && (tty->termios->c_cflag & CBAUD))
 		keyspan_pda_set_modem_info(serial, (1<<7) | (1<<2) );
 	else
 		keyspan_pda_set_modem_info(serial, 0);
@@ -690,13 +679,14 @@ error:
 }
 
 
-static void keyspan_pda_close(struct usb_serial_port *port, struct file *filp)
+static void keyspan_pda_close(struct tty_struct *tty,
+			struct usb_serial_port *port, struct file *filp)
 {
 	struct usb_serial *serial = port->serial;
 
 	if (serial->dev) {
 		/* the normal serial device seems to always shut off DTR and RTS now */
-		if (port->tty->termios->c_cflag & HUPCL)
+		if (tty->termios->c_cflag & HUPCL)
 			keyspan_pda_set_modem_info(serial, 0);
 
 		/* shutdown our bulk reads and writes */
@@ -832,7 +822,6 @@ static struct usb_serial_driver keyspan_pda_device = {
 	.chars_in_buffer =	keyspan_pda_chars_in_buffer,
 	.throttle =		keyspan_pda_rx_throttle,
 	.unthrottle =		keyspan_pda_rx_unthrottle,
-	.ioctl =		keyspan_pda_ioctl,
 	.set_termios =		keyspan_pda_set_termios,
 	.break_ctl =		keyspan_pda_break_ctl,
 	.tiocmget =		keyspan_pda_tiocmget,