tty: riscom8 kref and tty_port_close

We need to kref this driver in order to use port_close

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 59 insertions, 72 deletions

diff --git a/drivers/char/riscom8.c b/drivers/char/riscom8.c
index 949999120258..7b5623b01903 100644
--- a/drivers/char/riscom8.c
+++ b/drivers/char/riscom8.c
@@ -343,7 +343,7 @@ static void rc_receive_exc(struct riscom_board const *bp)
         if (port == NULL)
                 return;
 
-        tty = port->port.tty;
+        tty = tty_port_tty_get(&port->port);
 
 #ifdef RC_REPORT_OVERRUN
         status = rc_in(bp, CD180_RCSR);
@@ -355,18 +355,18 @@ static void rc_receive_exc(struct riscom_board const *bp)
 #endif
         ch = rc_in(bp, CD180_RDR);
         if (!status)
-                return;
+                goto out;
         if (status & RCSR_TOUT)  {
                 printk(KERN_WARNING "rc%d: port %d: Receiver timeout. "
                                     "Hardware problems ?\n",
                        board_No(bp), port_No(port));
-                return;
+                goto out;
 
         } else if (status & RCSR_BREAK)  {
                 printk(KERN_INFO "rc%d: port %d: Handling break...\n",
                        board_No(bp), port_No(port));
                 flag = TTY_BREAK;
-                if (port->port.flags & ASYNC_SAK)
+                if (tty && (port->port.flags & ASYNC_SAK))
                         do_SAK(tty);
 
         } else if (status & RCSR_PE)
@@ -380,8 +380,12 @@ static void rc_receive_exc(struct riscom_board const *bp)
         else
                 flag = TTY_NORMAL;
 
-        tty_insert_flip_char(tty, ch, flag);
-        tty_flip_buffer_push(tty);
+        if (tty) {
+                tty_insert_flip_char(tty, ch, flag);
+                tty_flip_buffer_push(tty);
+        }
+out:
+        tty_kref_put(tty);
 }
 
 static void rc_receive(struct riscom_board const *bp)
@@ -394,7 +398,7 @@ static void rc_receive(struct riscom_board const *bp)
         if (port == NULL)
                 return;
 
-        tty = port->port.tty;
+        tty = tty_port_tty_get(&port->port);
 
         count = rc_in(bp, CD180_RDCR);
 
@@ -403,15 +407,14 @@ static void rc_receive(struct riscom_board const *bp)
 #endif
 
         while (count--)  {
-                if (tty_buffer_request_room(tty, 1) == 0)  {
-                        printk(KERN_WARNING "rc%d: port %d: Working around "
-                                            "flip buffer overflow.\n",
-                               board_No(bp), port_No(port));
-                        break;
-                }
-                tty_insert_flip_char(tty, rc_in(bp, CD180_RDR), TTY_NORMAL);
+                u8 ch = rc_in(bp, CD180_RDR);
+                if (tty)
+                        tty_insert_flip_char(tty, ch, TTY_NORMAL);
+        }
+        if (tty) {
+                tty_flip_buffer_push(tty);
+                tty_kref_put(tty);
         }
-        tty_flip_buffer_push(tty);
 }
 
 static void rc_transmit(struct riscom_board const *bp)
@@ -424,22 +427,22 @@ static void rc_transmit(struct riscom_board const *bp)
         if (port == NULL)
                 return;
 
-        tty = port->port.tty;
+        tty = tty_port_tty_get(&port->port);
 
         if (port->IER & IER_TXEMPTY) {
                 /* FIFO drained */
                 rc_out(bp, CD180_CAR, port_No(port));
                 port->IER &= ~IER_TXEMPTY;
                 rc_out(bp, CD180_IER, port->IER);
-                return;
+                goto out;
         }
 
         if ((port->xmit_cnt <= 0 && !port->break_length)
-            || tty->stopped || tty->hw_stopped)  {
+            || (tty && (tty->stopped || tty->hw_stopped)))  {
                 rc_out(bp, CD180_CAR, port_No(port));
                 port->IER &= ~IER_TXRDY;
                 rc_out(bp, CD180_IER, port->IER);
-                return;
+                goto out;
         }
 
         if (port->break_length)  {
@@ -480,8 +483,10 @@ static void rc_transmit(struct riscom_board const *bp)
                 port->IER &= ~IER_TXRDY;
                 rc_out(bp, CD180_IER, port->IER);
         }
-        if (port->xmit_cnt <= port->wakeup_chars)
+        if (tty && port->xmit_cnt <= port->wakeup_chars)
                 tty_wakeup(tty);
+out:
+        tty_kref_put(tty);
 }
 
 static void rc_check_modem(struct riscom_board const *bp)
@@ -494,37 +499,43 @@ static void rc_check_modem(struct riscom_board const *bp)
         if (port == NULL)
                 return;
 
-        tty = port->port.tty;
+        tty = tty_port_tty_get(&port->port);
 
         mcr = rc_in(bp, CD180_MCR);
         if (mcr & MCR_CDCHG) {
                 if (rc_in(bp, CD180_MSVR) & MSVR_CD)
                         wake_up_interruptible(&port->port.open_wait);
-                else
+                else if (tty)
                         tty_hangup(tty);
         }
 
 #ifdef RISCOM_BRAIN_DAMAGED_CTS
         if (mcr & MCR_CTSCHG)  {
                 if (rc_in(bp, CD180_MSVR) & MSVR_CTS)  {
-                        tty->hw_stopped = 0;
                         port->IER |= IER_TXRDY;
-                        if (port->xmit_cnt <= port->wakeup_chars)
-                                tty_wakeup(tty);
+                        if (tty) {
+                                tty->hw_stopped = 0;
+                                if (port->xmit_cnt <= port->wakeup_chars)
+                                        tty_wakeup(tty);
+                        }
                 } else  {
-                        tty->hw_stopped = 1;
+                        if (tty)
+                                tty->hw_stopped = 1;
                         port->IER &= ~IER_TXRDY;
                 }
                 rc_out(bp, CD180_IER, port->IER);
         }
         if (mcr & MCR_DSRCHG)  {
                 if (rc_in(bp, CD180_MSVR) & MSVR_DSR)  {
-                        tty->hw_stopped = 0;
                         port->IER |= IER_TXRDY;
-                        if (port->xmit_cnt <= port->wakeup_chars)
-                                tty_wakeup(tty);
+                        if (tty) {
+                                tty->hw_stopped = 0;
+                                if (port->xmit_cnt <= port->wakeup_chars)
+                                        tty_wakeup(tty);
+                        }
                 } else  {
-                        tty->hw_stopped = 1;
+                        if (tty)
+                                tty->hw_stopped = 1;
                         port->IER &= ~IER_TXRDY;
                 }
                 rc_out(bp, CD180_IER, port->IER);
@@ -533,6 +544,7 @@ static void rc_check_modem(struct riscom_board const *bp)
 
         /* Clear change bits */
         rc_out(bp, CD180_MCR, 0);
+        tty_kref_put(tty);
 }
 
 /* The main interrupt processing routine */
@@ -632,9 +644,9 @@ static void rc_shutdown_board(struct riscom_board *bp)
  * Setting up port characteristics.
  * Must be called with disabled interrupts
  */
-static void rc_change_speed(struct riscom_board *bp, struct riscom_port *port)
+static void rc_change_speed(struct tty_struct *tty, struct riscom_board *bp,
+                                                struct riscom_port *port)
 {
-        struct tty_struct *tty = port->port.tty;
         unsigned long baud;
         long tmp;
         unsigned char cor1 = 0, cor3 = 0;
@@ -781,7 +793,8 @@ static void rc_change_speed(struct riscom_board *bp, struct riscom_port *port)
 }
 
 /* Must be called with interrupts enabled */
-static int rc_setup_port(struct riscom_board *bp, struct riscom_port *port)
+static int rc_setup_port(struct tty_struct *tty, struct riscom_board *bp,
+                                                struct riscom_port *port)
 {
         unsigned long flags;
 
@@ -793,11 +806,11 @@ static int rc_setup_port(struct riscom_board *bp, struct riscom_port *port)
 
         spin_lock_irqsave(&riscom_lock, flags);
 
-        clear_bit(TTY_IO_ERROR, &port->port.tty->flags);
+        clear_bit(TTY_IO_ERROR, &tty->flags);
         if (port->port.count == 1)
                 bp->count++;
         port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
-        rc_change_speed(bp, port);
+        rc_change_speed(tty, bp, port);
         port->port.flags |= ASYNC_INITIALIZED;
 
         spin_unlock_irqrestore(&riscom_lock, flags);
@@ -898,9 +911,9 @@ static int rc_open(struct tty_struct *tty, struct file *filp)
 
         port->port.count++;
         tty->driver_data = port;
-        port->port.tty = tty;
+        tty_port_tty_set(&port->port, tty);
 
-        error = rc_setup_port(bp, port);
+        error = rc_setup_port(tty, bp, port);
         if (error == 0)
                 error = tty_port_block_til_ready(&port->port, tty, filp);
         return error;
@@ -921,7 +934,7 @@ static void rc_flush_buffer(struct tty_struct *tty)
         tty_wakeup(tty);
 }
 
-static void rc_close_port(struct tty_struct *tty, struct tty_port *port)
+static void rc_close_port(struct tty_port *port, struct tty_struct *tty)
 {
         unsigned long flags;
         struct riscom_port *rp = container_of(port, struct riscom_port, port);
@@ -966,14 +979,7 @@ static void rc_close(struct tty_struct *tty, struct file *filp)
 
         if (!port || rc_paranoia_check(port, tty->name, "close"))
                 return;
-
-        if (tty_port_close_start(&port->port, tty, filp) == 0)
-                return;
-
-        rc_close_port(tty, &port->port);
-        rc_flush_buffer(tty);
-
-        tty_port_close_end(&port->port, tty);
+        tty_port_close(&port->port, tty, filp);
 }
 
 static int rc_write(struct tty_struct *tty,
@@ -1175,7 +1181,7 @@ static int rc_send_break(struct tty_struct *tty, int length)
         return 0;
 }
 
-static int rc_set_serial_info(struct riscom_port *port,
+static int rc_set_serial_info(struct tty_struct *tty, struct riscom_port *port,
                                      struct serial_struct __user *newinfo)
 {
         struct serial_struct tmp;
@@ -1185,17 +1191,6 @@ static int rc_set_serial_info(struct riscom_port *port,
         if (copy_from_user(&tmp, newinfo, sizeof(tmp)))
                 return -EFAULT;
 
-#if 0
-        if ((tmp.irq != bp->irq) ||
-            (tmp.port != bp->base) ||
-            (tmp.type != PORT_CIRRUS) ||
-            (tmp.baud_base != (RC_OSCFREQ + CD180_TPC/2) / CD180_TPC) ||
-            (tmp.custom_divisor != 0) ||
-            (tmp.xmit_fifo_size != CD180_NFIFO) ||
-            (tmp.flags & ~RISCOM_LEGAL_FLAGS))
-                return -EINVAL;
-#endif
-
         change_speed = ((port->port.flags & ASYNC_SPD_MASK) !=
                         (tmp.flags & ASYNC_SPD_MASK));
 
@@ -1217,7 +1212,7 @@ static int rc_set_serial_info(struct riscom_port *port,
                 unsigned long flags;
 
                 spin_lock_irqsave(&riscom_lock, flags);
-                rc_change_speed(bp, port);
+                rc_change_speed(tty, bp, port);
                 spin_unlock_irqrestore(&riscom_lock, flags);
         }
         return 0;
@@ -1260,7 +1255,7 @@ static int rc_ioctl(struct tty_struct *tty, struct file *filp,
                 break;
         case TIOCSSERIAL:
                 lock_kernel();
-                retval = rc_set_serial_info(port, argp);
+                retval = rc_set_serial_info(tty, port, argp);
                 unlock_kernel();
                 break;
         default:
@@ -1355,21 +1350,12 @@ static void rc_start(struct tty_struct *tty)
 static void rc_hangup(struct tty_struct *tty)
 {
         struct riscom_port *port = tty->driver_data;
-        struct riscom_board *bp;
-        unsigned long flags;
 
         if (rc_paranoia_check(port, tty->name, "rc_hangup"))
                 return;
 
-        bp = port_Board(port);
-
-        rc_shutdown_port(tty, bp, port);
-        spin_lock_irqsave(&port->port.lock, flags);
-        port->port.count = 0;
-        port->port.flags &= ~ASYNC_NORMAL_ACTIVE;
-        port->port.tty = NULL;
-        wake_up_interruptible(&port->port.open_wait);
-        spin_unlock_irqrestore(&port->port.lock, flags);
+        rc_shutdown_port(tty, port_Board(port), port);
+        tty_port_hangup(&port->port);
 }
 
 static void rc_set_termios(struct tty_struct *tty,
@@ -1382,7 +1368,7 @@ static void rc_set_termios(struct tty_struct *tty,
                 return;
 
         spin_lock_irqsave(&riscom_lock, flags);
-        rc_change_speed(port_Board(port), port);
+        rc_change_speed(tty, port_Board(port), port);
         spin_unlock_irqrestore(&riscom_lock, flags);
 
         if ((old_termios->c_cflag & CRTSCTS) &&
@@ -1415,6 +1401,7 @@ static const struct tty_operations riscom_ops = {
 
 static const struct tty_port_operations riscom_port_ops = {
         .carrier_raised = carrier_raised,
+        .shutdown = rc_close_port,
 };