tty: moxa: Kill the use of lock_kernel

[safe/jmp/linux-2.6] / drivers / char / moxa.c

diff --git a/drivers/char/moxa.c b/drivers/char/moxa.c
index 7ab720f..d53fac5 100644 (file)
--- a/drivers/char/moxa.c
+++ b/drivers/char/moxa.c
@@ -34,7 +34,6 @@
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
 #include <linux/major.h>
-#include <linux/smp_lock.h>
 #include <linux/string.h>
 #include <linux/fcntl.h>
 #include <linux/ptrace.h>
@@ -139,7 +138,7 @@ struct moxa_port {
        int cflag;
        unsigned long statusflags;
 
-       u8 DCDState;
+       u8 DCDState;            /* Protected by the port lock */
        u8 lineCtrl;
        u8 lowChkFlag;
 };
@@ -154,7 +153,6 @@ struct mon_str {
 #define TXSTOPPED      1
 #define LOWWAIT        2
 #define EMPTYWAIT      3
-#define THROTTLE       4
 
 #define SERIAL_DO_RESTART
 
@@ -194,8 +192,6 @@ static int moxa_write(struct tty_struct *, const unsigned char *, int);
 static int moxa_write_room(struct tty_struct *);
 static void moxa_flush_buffer(struct tty_struct *);
 static int moxa_chars_in_buffer(struct tty_struct *);
-static void moxa_throttle(struct tty_struct *);
-static void moxa_unthrottle(struct tty_struct *);
 static void moxa_set_termios(struct tty_struct *, struct ktermios *);
 static void moxa_stop(struct tty_struct *);
 static void moxa_start(struct tty_struct *);
@@ -205,7 +201,6 @@ static int moxa_tiocmset(struct tty_struct *tty, struct file *file,
                         unsigned int set, unsigned int clear);
 static void moxa_poll(unsigned long);
 static void moxa_set_tty_param(struct tty_struct *, struct ktermios *);
-static void moxa_setup_empty_event(struct tty_struct *);
 static void moxa_shutdown(struct tty_port *);
 static int moxa_carrier_raised(struct tty_port *);
 static void moxa_dtr_rts(struct tty_port *, int);
@@ -415,8 +410,6 @@ static const struct tty_operations moxa_ops = {
        .flush_buffer = moxa_flush_buffer,
        .chars_in_buffer = moxa_chars_in_buffer,
        .ioctl = moxa_ioctl,
-       .throttle = moxa_throttle,
-       .unthrottle = moxa_unthrottle,
        .set_termios = moxa_set_termios,
        .stop = moxa_stop,
        .start = moxa_start,
@@ -1146,9 +1139,9 @@ static int moxa_carrier_raised(struct tty_port *port)
        struct moxa_port *ch = container_of(port, struct moxa_port, port);
        int dcd;
 
-       spin_lock_bh(&moxa_lock);
+       spin_lock_irq(&port->lock);
        dcd = ch->DCDState;
-       spin_unlock_bh(&moxa_lock);
+       spin_unlock_irq(&port->lock);
        return dcd;
 }
 
@@ -1256,32 +1249,21 @@ static int moxa_chars_in_buffer(struct tty_struct *tty)
        struct moxa_port *ch = tty->driver_data;
        int chars;
 
-       lock_kernel();
        chars = MoxaPortTxQueue(ch);
-       if (chars) {
+       if (chars)
                /*
                 * Make it possible to wakeup anything waiting for output
                 * in tty_ioctl.c, etc.
                 */
-               if (!test_bit(EMPTYWAIT, &ch->statusflags))
-                       moxa_setup_empty_event(tty);
-       }
-       unlock_kernel();
+               set_bit(EMPTYWAIT, &ch->statusflags);
        return chars;
 }
 
 static int moxa_tiocmget(struct tty_struct *tty, struct file *file)
 {
-       struct moxa_port *ch;
+       struct moxa_port *ch = tty->driver_data;
        int flag = 0, dtr, rts;
 
-       mutex_lock(&moxa_openlock);
-       ch = tty->driver_data;
-       if (!ch) {
-               mutex_unlock(&moxa_openlock);
-               return -EINVAL;
-       }
-
        MoxaPortGetLineOut(ch, &dtr, &rts);
        if (dtr)
                flag |= TIOCM_DTR;
@@ -1294,7 +1276,6 @@ static int moxa_tiocmget(struct tty_struct *tty, struct file *file)
                flag |= TIOCM_DSR;
        if (dtr & 4)
                flag |= TIOCM_CD;
-       mutex_unlock(&moxa_openlock);
        return flag;
 }
 
@@ -1327,20 +1308,6 @@ static int moxa_tiocmset(struct tty_struct *tty, struct file *file,
        return 0;
 }
 
-static void moxa_throttle(struct tty_struct *tty)
-{
-       struct moxa_port *ch = tty->driver_data;
-
-       set_bit(THROTTLE, &ch->statusflags);
-}
-
-static void moxa_unthrottle(struct tty_struct *tty)
-{
-       struct moxa_port *ch = tty->driver_data;
-
-       clear_bit(THROTTLE, &ch->statusflags);
-}
-
 static void moxa_set_termios(struct tty_struct *tty,
                struct ktermios *old_termios)
 {
@@ -1387,15 +1354,20 @@ static void moxa_hangup(struct tty_struct *tty)
 static void moxa_new_dcdstate(struct moxa_port *p, u8 dcd)
 {
        struct tty_struct *tty;
+       unsigned long flags;
        dcd = !!dcd;
 
+       spin_lock_irqsave(&p->port.lock, flags);
        if (dcd != p->DCDState) {
+               p->DCDState = dcd;
+               spin_unlock_irqrestore(&p->port.lock, flags);
                tty = tty_port_tty_get(&p->port);
                if (tty && C_CLOCAL(tty) && !dcd)
                        tty_hangup(tty);
                tty_kref_put(tty);
        }
-       p->DCDState = dcd;
+       else
+               spin_unlock_irqrestore(&p->port.lock, flags);
 }
 
 static int moxa_poll_port(struct moxa_port *p, unsigned int handle,
@@ -1418,7 +1390,7 @@ static int moxa_poll_port(struct moxa_port *p, unsigned int handle,
                        tty_wakeup(tty);
                }
 
-               if (inited && !test_bit(THROTTLE, &p->statusflags) &&
+               if (inited && !test_bit(TTY_THROTTLED, &tty->flags) &&
                                MoxaPortRxQueue(p) > 0) { /* RX */
                        MoxaPortReadData(p);
                        tty_schedule_flip(tty);
@@ -1525,12 +1497,6 @@ static void moxa_set_tty_param(struct tty_struct *tty, struct ktermios *old_term
        tty_encode_baud_rate(tty, baud, baud);
 }
 
-static void moxa_setup_empty_event(struct tty_struct *tty)
-{
-       struct moxa_port *ch = tty->driver_data;
-       set_bit(EMPTYWAIT, &ch->statusflags);
-}
-
 /*****************************************************************************
  *     Driver level functions:                                              *
  *****************************************************************************/
@@ -1897,9 +1863,7 @@ static int MoxaPortLineStatus(struct moxa_port *port)
        val &= 0x0B;
        if (val & 8)
                val |= 4;
-       spin_lock_bh(&moxa_lock);
        moxa_new_dcdstate(port, val & 8);
-       spin_unlock_bh(&moxa_lock);
        val &= 7;
        return val;
 }