Merge tag 'tty-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull TTY updates from Greg Kroah-Hartman:
 "Here's the big TTY/serial driver pull request for the 3.5-rc1 merge
  window.

  Nothing major in here, just lots of incremental changes from Alan and
  Jiri reworking some tty core things to behave better and to get a more
  solid grasp on some of the nasty tty locking issues.

  There are a few tty and serial driver updates in here as well.

  All of this has been in the linux-next releases for a while with no
  problems.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'tty-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (115 commits)
  serial: bfin_uart: Make MMR access compatible with 32 bits bf609 style controller.
  serial: bfin_uart: RTS and CTS MMRs can be either 16-bit width or 32-bit width.
  serial: bfin_uart: narrow the reboot condition in DMA tx interrupt
  serial: bfin_uart: Adapt bf5xx serial driver to bf60x serial4 controller.
  Revert "serial_core: Update buffer overrun statistics."
  tty: hvc_xen: NULL dereference on allocation failure
  tty: Fix LED error return
  tty: Allow uart_register/unregister/register
  tty: move global ldisc idle waitqueue to the individual ldisc
  serial8250-em: Add DT support
  serial8250-em: clk_get() IS_ERR() error handling fix
  serial_core: Update buffer overrun statistics.
  tty: drop the pty lock during hangup
  cris: fix missing tty arg in wait_event_interruptible_tty call
  tty/amiserial: Add missing argument for tty_unlock()
  tty_lock: Localise the lock
  pty: Lock the devpts bits privately
  tty_lock: undo the old tty_lock use on the ctty
  serial8250-em: Emma Mobile UART driver V2
  Add missing call to uart_update_timeout()
  ...

1 files changed, 44 insertions, 61 deletions

diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c
index 042c1a99520f..62f30b46fa42 100644
--- a/drivers/net/usb/hso.c
+++ b/drivers/net/usb/hso.c
@@ -106,13 +106,6 @@
 
 #define MAX_RX_URBS                     2
 
-static inline struct hso_serial *get_serial_by_tty(struct tty_struct *tty)
-{
-        if (tty)
-                return tty->driver_data;
-        return NULL;
-}
-
 /*****************************************************************************/
 /* Debugging functions                                                       */
 /*****************************************************************************/
@@ -255,9 +248,8 @@ struct hso_serial {
         u8 dtr_state;
         unsigned tx_urb_used:1;
 
+        struct tty_port port;
         /* from usb_serial_port */
-        struct tty_struct *tty;
-        int open_count;
         spinlock_t serial_lock;
 
         int (*write_data) (struct hso_serial *serial);
@@ -1114,7 +1106,7 @@ static void hso_init_termios(struct ktermios *termios)
 static void _hso_serial_set_termios(struct tty_struct *tty,
                                     struct ktermios *old)
 {
-        struct hso_serial *serial = get_serial_by_tty(tty);
+        struct hso_serial *serial = tty->driver_data;
         struct ktermios *termios;
 
         if (!serial) {
@@ -1190,7 +1182,7 @@ static void put_rxbuf_data_and_resubmit_ctrl_urb(struct hso_serial *serial)
         struct urb *urb;
 
         urb = serial->rx_urb[0];
-        if (serial->open_count > 0) {
+        if (serial->port.count > 0) {
                 count = put_rxbuf_data(urb, serial);
                 if (count == -1)
                         return;
@@ -1226,7 +1218,7 @@ static void hso_std_serial_read_bulk_callback(struct urb *urb)
         DUMP1(urb->transfer_buffer, urb->actual_length);
 
         /* Anyone listening? */
-        if (serial->open_count == 0)
+        if (serial->port.count == 0)
                 return;
 
         if (status == 0) {
@@ -1268,7 +1260,7 @@ static void hso_unthrottle_tasklet(struct hso_serial *serial)
 
 static  void hso_unthrottle(struct tty_struct *tty)
 {
-        struct hso_serial *serial = get_serial_by_tty(tty);
+        struct hso_serial *serial = tty->driver_data;
 
         tasklet_hi_schedule(&serial->unthrottle_tasklet);
 }
@@ -1304,15 +1296,12 @@ static int hso_serial_open(struct tty_struct *tty, struct file *filp)
         kref_get(&serial->parent->ref);
 
         /* setup */
-        spin_lock_irq(&serial->serial_lock);
         tty->driver_data = serial;
-        tty_kref_put(serial->tty);
-        serial->tty = tty_kref_get(tty);
-        spin_unlock_irq(&serial->serial_lock);
+        tty_port_tty_set(&serial->port, tty);
 
         /* check for port already opened, if not set the termios */
-        serial->open_count++;
-        if (serial->open_count == 1) {
+        serial->port.count++;
+        if (serial->port.count == 1) {
                 serial->rx_state = RX_IDLE;
                 /* Force default termio settings */
                 _hso_serial_set_termios(tty, NULL);
@@ -1324,7 +1313,7 @@ static int hso_serial_open(struct tty_struct *tty, struct file *filp)
                 result = hso_start_serial_device(serial->parent, GFP_KERNEL);
                 if (result) {
                         hso_stop_serial_device(serial->parent);
-                        serial->open_count--;
+                        serial->port.count--;
                         kref_put(&serial->parent->ref, hso_serial_ref_free);
                 }
         } else {
@@ -1361,17 +1350,11 @@ static void hso_serial_close(struct tty_struct *tty, struct file *filp)
 
         /* reset the rts and dtr */
         /* do the actual close */
-        serial->open_count--;
+        serial->port.count--;
 
-        if (serial->open_count <= 0) {
-                serial->open_count = 0;
-                spin_lock_irq(&serial->serial_lock);
-                if (serial->tty == tty) {
-                        serial->tty->driver_data = NULL;
-                        serial->tty = NULL;
-                        tty_kref_put(tty);
-                }
-                spin_unlock_irq(&serial->serial_lock);
+        if (serial->port.count <= 0) {
+                serial->port.count = 0;
+                tty_port_tty_set(&serial->port, NULL);
                 if (!usb_gone)
                         hso_stop_serial_device(serial->parent);
                 tasklet_kill(&serial->unthrottle_tasklet);
@@ -1390,7 +1373,7 @@ static void hso_serial_close(struct tty_struct *tty, struct file *filp)
 static int hso_serial_write(struct tty_struct *tty, const unsigned char *buf,
                             int count)
 {
-        struct hso_serial *serial = get_serial_by_tty(tty);
+        struct hso_serial *serial = tty->driver_data;
         int space, tx_bytes;
         unsigned long flags;
 
@@ -1422,7 +1405,7 @@ out:
 /* how much room is there for writing */
 static int hso_serial_write_room(struct tty_struct *tty)
 {
-        struct hso_serial *serial = get_serial_by_tty(tty);
+        struct hso_serial *serial = tty->driver_data;
         int room;
         unsigned long flags;
 
@@ -1437,7 +1420,7 @@ static int hso_serial_write_room(struct tty_struct *tty)
 /* setup the term */
 static void hso_serial_set_termios(struct tty_struct *tty, struct ktermios *old)
 {
-        struct hso_serial *serial = get_serial_by_tty(tty);
+        struct hso_serial *serial = tty->driver_data;
         unsigned long flags;
 
         if (old)
@@ -1446,7 +1429,7 @@ static void hso_serial_set_termios(struct tty_struct *tty, struct ktermios *old)
 
         /* the actual setup */
         spin_lock_irqsave(&serial->serial_lock, flags);
-        if (serial->open_count)
+        if (serial->port.count)
                 _hso_serial_set_termios(tty, old);
         else
                 tty->termios = old;
@@ -1458,7 +1441,7 @@ static void hso_serial_set_termios(struct tty_struct *tty, struct ktermios *old)
 /* how many characters in the buffer */
 static int hso_serial_chars_in_buffer(struct tty_struct *tty)
 {
-        struct hso_serial *serial = get_serial_by_tty(tty);
+        struct hso_serial *serial = tty->driver_data;
         int chars;
         unsigned long flags;
 
@@ -1629,7 +1612,7 @@ static int hso_get_count(struct tty_struct *tty,
                   struct serial_icounter_struct *icount)
 {
         struct uart_icount cnow;
-        struct hso_serial *serial = get_serial_by_tty(tty);
+        struct hso_serial *serial = tty->driver_data;
         struct hso_tiocmget  *tiocmget = serial->tiocmget;
 
         memset(icount, 0, sizeof(struct serial_icounter_struct));
@@ -1659,7 +1642,7 @@ static int hso_get_count(struct tty_struct *tty,
 static int hso_serial_tiocmget(struct tty_struct *tty)
 {
         int retval;
-        struct hso_serial *serial = get_serial_by_tty(tty);
+        struct hso_serial *serial = tty->driver_data;
         struct hso_tiocmget  *tiocmget;
         u16 UART_state_bitmap;
 
@@ -1693,7 +1676,7 @@ static int hso_serial_tiocmset(struct tty_struct *tty,
         int val = 0;
         unsigned long flags;
         int if_num;
-        struct hso_serial *serial = get_serial_by_tty(tty);
+        struct hso_serial *serial = tty->driver_data;
 
         /* sanity check */
         if (!serial) {
@@ -1733,7 +1716,7 @@ static int hso_serial_tiocmset(struct tty_struct *tty,
 static int hso_serial_ioctl(struct tty_struct *tty,
                             unsigned int cmd, unsigned long arg)
 {
-        struct hso_serial *serial =  get_serial_by_tty(tty);
+        struct hso_serial *serial = tty->driver_data;
         int ret = 0;
         D4("IOCTL cmd: %d, arg: %ld", cmd, arg);
 
@@ -1905,7 +1888,7 @@ static void intr_callback(struct urb *urb)
                                 D1("Pending read interrupt on port %d\n", i);
                                 spin_lock(&serial->serial_lock);
                                 if (serial->rx_state == RX_IDLE &&
-                                        serial->open_count > 0) {
+                                        serial->port.count > 0) {
                                         /* Setup and send a ctrl req read on
                                          * port i */
                                         if (!serial->rx_urb_filled[0]) {
@@ -1954,14 +1937,13 @@ static void hso_std_serial_write_bulk_callback(struct urb *urb)
 
         spin_lock(&serial->serial_lock);
         serial->tx_urb_used = 0;
-        tty = tty_kref_get(serial->tty);
         spin_unlock(&serial->serial_lock);
         if (status) {
                 handle_usb_error(status, __func__, serial->parent);
-                tty_kref_put(tty);
                 return;
         }
         hso_put_activity(serial->parent);
+        tty = tty_port_tty_get(&serial->port);
         if (tty) {
                 tty_wakeup(tty);
                 tty_kref_put(tty);
@@ -2001,7 +1983,6 @@ static void ctrl_callback(struct urb *urb)
         struct hso_serial *serial = urb->context;
         struct usb_ctrlrequest *req;
         int status = urb->status;
-        struct tty_struct *tty;
 
         /* sanity check */
         if (!serial)
@@ -2009,11 +1990,9 @@ static void ctrl_callback(struct urb *urb)
 
         spin_lock(&serial->serial_lock);
         serial->tx_urb_used = 0;
-        tty = tty_kref_get(serial->tty);
         spin_unlock(&serial->serial_lock);
         if (status) {
                 handle_usb_error(status, __func__, serial->parent);
-                tty_kref_put(tty);
                 return;
         }
 
@@ -2031,13 +2010,15 @@ static void ctrl_callback(struct urb *urb)
                 put_rxbuf_data_and_resubmit_ctrl_urb(serial);
                 spin_unlock(&serial->serial_lock);
         } else {
+                struct tty_struct *tty = tty_port_tty_get(&serial->port);
                 hso_put_activity(serial->parent);
-                if (tty)
+                if (tty) {
                         tty_wakeup(tty);
+                        tty_kref_put(tty);
+                }
                 /* response to a write command */
                 hso_kick_transmit(serial);
         }
-        tty_kref_put(tty);
 }
 
 /* handle RX data for serial port */
@@ -2053,8 +2034,7 @@ static int put_rxbuf_data(struct urb *urb, struct hso_serial *serial)
                 return -2;
         }
 
-        /* All callers to put_rxbuf_data hold serial_lock */
-        tty = tty_kref_get(serial->tty);
+        tty = tty_port_tty_get(&serial->port);
 
         /* Push data to tty */
         if (tty) {
@@ -2074,12 +2054,12 @@ static int put_rxbuf_data(struct urb *urb, struct hso_serial *serial)
                         write_length_remaining -= curr_write_len;
                         tty_flip_buffer_push(tty);
                 }
+                tty_kref_put(tty);
         }
         if (write_length_remaining == 0) {
                 serial->curr_rx_urb_offset = 0;
                 serial->rx_urb_filled[hso_urb_to_index(serial, urb)] = 0;
         }
-        tty_kref_put(tty);
         return write_length_remaining;
 }
 
@@ -2320,6 +2300,7 @@ static int hso_serial_common_create(struct hso_serial *serial, int num_urbs,
         serial->minor = minor;
         serial->magic = HSO_SERIAL_MAGIC;
         spin_lock_init(&serial->serial_lock);
+        tty_port_init(&serial->port);
         serial->num_rx_urbs = num_urbs;
 
         /* RX, allocate urb and initialize */
@@ -3098,7 +3079,7 @@ static int hso_resume(struct usb_interface *iface)
         /* Start all serial ports */
         for (i = 0; i < HSO_SERIAL_TTY_MINORS; i++) {
                 if (serial_table[i] && (serial_table[i]->interface == iface)) {
-                        if (dev2ser(serial_table[i])->open_count) {
+                        if (dev2ser(serial_table[i])->port.count) {
                                 result =
                                     hso_start_serial_device(serial_table[i], GFP_NOIO);
                                 hso_kick_transmit(dev2ser(serial_table[i]));
@@ -3172,13 +3153,12 @@ static void hso_free_interface(struct usb_interface *interface)
                 if (serial_table[i] &&
                     (serial_table[i]->interface == interface)) {
                         hso_dev = dev2ser(serial_table[i]);
-                        spin_lock_irq(&hso_dev->serial_lock);
-                        tty = tty_kref_get(hso_dev->tty);
-                        spin_unlock_irq(&hso_dev->serial_lock);
-                        if (tty)
+                        tty = tty_port_tty_get(&hso_dev->port);
+                        if (tty) {
                                 tty_hangup(tty);
+                                tty_kref_put(tty);
+                        }
                         mutex_lock(&hso_dev->parent->mutex);
-                        tty_kref_put(tty);
                         hso_dev->parent->usb_gone = 1;
                         mutex_unlock(&hso_dev->parent->mutex);
                         kref_put(&serial_table[i]->ref, hso_serial_ref_free);
@@ -3313,7 +3293,6 @@ static int __init hso_init(void)
                 return -ENOMEM;
 
         /* fill in all needed values */
-        tty_drv->magic = TTY_DRIVER_MAGIC;
         tty_drv->driver_name = driver_name;
         tty_drv->name = tty_filename;
 
@@ -3334,7 +3313,7 @@ static int __init hso_init(void)
         if (result) {
                 printk(KERN_ERR "%s - tty_register_driver failed(%d)\n",
                         __func__, result);
-                return result;
+                goto err_free_tty;
         }
 
         /* register this module as an usb driver */
@@ -3342,13 +3321,16 @@ static int __init hso_init(void)
         if (result) {
                 printk(KERN_ERR "Could not register hso driver? error: %d\n",
                         result);
-                /* cleanup serial interface */
-                tty_unregister_driver(tty_drv);
-                return result;
+                goto err_unreg_tty;
         }
 
         /* done */
         return 0;
+err_unreg_tty:
+        tty_unregister_driver(tty_drv);
+err_free_tty:
+        put_tty_driver(tty_drv);
+        return result;
 }
 
 static void __exit hso_exit(void)
@@ -3356,6 +3338,7 @@ static void __exit hso_exit(void)
         printk(KERN_INFO "hso: unloaded\n");
 
         tty_unregister_driver(tty_drv);
+        put_tty_driver(tty_drv);
         /* deregister the usb driver */
         usb_deregister(&hso_driver);
 }