Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff
[linux-2.6.git] / drivers / tc / zs.c
index 4382ee6..2dffa8e 100644 (file)
@@ -6,7 +6,7 @@
  *
  * DECstation changes
  * Copyright (C) 1998-2000 Harald Koerfgen
- * Copyright (C) 2000, 2001, 2002, 2003, 2004  Maciej W. Rozycki
+ * Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005  Maciej W. Rozycki
  *
  * For the rest of the code the original Copyright applies:
  * Copyright (C) 1996 Paul Mackerras (Paul.Mackerras@cs.anu.edu.au)
@@ -55,6 +55,7 @@
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/ioport.h>
+#include <linux/spinlock.h>
 #ifdef CONFIG_SERIAL_DEC_CONSOLE
 #include <linux/console.h>
 #endif
 #include <asm/pgtable.h>
 #include <asm/irq.h>
 #include <asm/system.h>
-#include <asm/uaccess.h>
 #include <asm/bootinfo.h>
-#include <asm/dec/serial.h>
 
-#ifdef CONFIG_MACH_DECSTATION
 #include <asm/dec/interrupts.h>
+#include <asm/dec/ioasic_addrs.h>
 #include <asm/dec/machtype.h>
+#include <asm/dec/serial.h>
+#include <asm/dec/system.h>
 #include <asm/dec/tc.h>
-#include <asm/dec/ioasic_addrs.h>
-#endif
+
 #ifdef CONFIG_KGDB
 #include <asm/kgdb.h>
 #endif
@@ -128,6 +128,8 @@ static struct zs_parms ds_parms = {
 
 #define BUS_PRESENT (DS_BUS_PRESENT)
 
+DEFINE_SPINLOCK(zs_lock);
+
 struct dec_zschannel zs_channels[NUM_CHANNELS];
 struct dec_serial zs_soft[NUM_CHANNELS];
 int zs_channels_found;
@@ -159,8 +161,6 @@ static unsigned char zs_init_regs[16] __initdata = {
        0                               /* write 15 */
 };
 
-DECLARE_TASK_QUEUE(tq_zs_serial);
-
 static struct tty_driver *serial_driver;
 
 /* serial subtype definitions */
@@ -186,24 +186,10 @@ static struct tty_driver *serial_driver;
 #define RS_STROBE_TIME 10
 #define RS_ISR_PASS_LIMIT 256
 
-#define _INLINE_ inline
-
 static void probe_sccs(void);
 static void change_speed(struct dec_serial *info);
 static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
 
-/*
- * tmp_buf is used as a temporary buffer by serial_write.  We need to
- * lock it in case the copy_from_user blocks while swapping in a page,
- * and some other program tries to do a serial write at the same time.
- * Since the lock will only come under contention when the system is
- * swapping and available memory is low, it makes sense to share one
- * buffer across all the serial ports, since it significantly saves
- * memory if large numbers of serial ports are open.
- */
-static unsigned char tmp_buf[4096]; /* This is cheating */
-static DECLARE_MUTEX(tmp_buf_sem);
-
 static inline int serial_paranoia_check(struct dec_serial *info,
                                        char *name, const char *routine)
 {
@@ -306,8 +292,7 @@ static inline void zs_rtsdtr(struct dec_serial *info, int which, int set)
 {
         unsigned long flags;
 
-
-       save_flags(flags); cli();
+       spin_lock_irqsave(&zs_lock, flags);
        if (info->zs_channel != info->zs_chan_a) {
                if (set) {
                        info->zs_chan_a->curregs[5] |= (which & (RTS | DTR));
@@ -316,7 +301,7 @@ static inline void zs_rtsdtr(struct dec_serial *info, int which, int set)
                }
                write_zsreg(info->zs_chan_a, 5, info->zs_chan_a->curregs[5]);
        }
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
 }
 
 /* Utility routines for the Zilog */
@@ -357,16 +342,13 @@ static inline void rs_recv_clear(struct dec_zschannel *zsc)
  * This routine is used by the interrupt handler to schedule
  * processing in the software interrupt portion of the driver.
  */
-static _INLINE_ void rs_sched_event(struct dec_serial *info,
-                                 int event)
+static void rs_sched_event(struct dec_serial *info, int event)
 {
        info->event |= 1 << event;
-       queue_task(&info->tqueue, &tq_zs_serial);
-       mark_bh(SERIAL_BH);
+       tasklet_schedule(&info->tlet);
 }
 
-static _INLINE_ void receive_chars(struct dec_serial *info,
-                                  struct pt_regs *regs)
+static void receive_chars(struct dec_serial *info, struct pt_regs *regs)
 {
        struct tty_struct *tty = info->tty;
        unsigned char ch, stat, flag;
@@ -456,7 +438,7 @@ static void transmit_chars(struct dec_serial *info)
                rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
 }
 
-static _INLINE_ void status_handle(struct dec_serial *info)
+static void status_handle(struct dec_serial *info)
 {
        unsigned char stat;
 
@@ -509,9 +491,10 @@ static _INLINE_ void status_handle(struct dec_serial *info)
 /*
  * This is the serial driver's generic interrupt routine
  */
-void rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
+static irqreturn_t rs_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 {
        struct dec_serial *info = (struct dec_serial *) dev_id;
+       irqreturn_t status = IRQ_NONE;
        unsigned char zs_intreg;
        int shift;
 
@@ -533,6 +516,8 @@ void rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
                if ((zs_intreg & CHAN_IRQMASK) == 0)
                        break;
 
+               status = IRQ_HANDLED;
+
                if (zs_intreg & CHBRxIP) {
                        receive_chars(info, regs);
                }
@@ -546,6 +531,8 @@ void rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
 
        /* Why do we need this ? */
        write_zsreg(info->zs_channel, 0, RES_H_IUS);
+
+       return status;
 }
 
 #ifdef ZS_DEBUG_REGS
@@ -590,12 +577,12 @@ static void rs_stop(struct tty_struct *tty)
                return;
 
 #if 1
-       save_flags(flags); cli();
+       spin_lock_irqsave(&zs_lock, flags);
        if (info->zs_channel->curregs[5] & TxENAB) {
                info->zs_channel->curregs[5] &= ~TxENAB;
                write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
        }
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
 #endif
 }
 
@@ -607,7 +594,7 @@ static void rs_start(struct tty_struct *tty)
        if (serial_paranoia_check(info, tty->name, "rs_start"))
                return;
 
-       save_flags(flags); cli();
+       spin_lock_irqsave(&zs_lock, flags);
 #if 1
        if (info->xmit_cnt && info->xmit_buf && !(info->zs_channel->curregs[5] & TxENAB)) {
                info->zs_channel->curregs[5] |= TxENAB;
@@ -618,7 +605,7 @@ static void rs_start(struct tty_struct *tty)
                transmit_chars(info);
        }
 #endif
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
 }
 
 /*
@@ -630,12 +617,8 @@ static void rs_start(struct tty_struct *tty)
  * interrupt driver proper are done; the interrupt driver schedules
  * them using rs_sched_event(), and they get done here.
  */
-static void do_serial_bh(void)
-{
-       run_task_queue(&tq_zs_serial);
-}
 
-static void do_softint(void *private_)
+static void do_softint(unsigned long private_)
 {
        struct dec_serial       *info = (struct dec_serial *) private_;
        struct tty_struct       *tty;
@@ -646,10 +629,11 @@ static void do_softint(void *private_)
 
        if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
                tty_wakeup(tty);
+               wake_up_interruptible(&tty->write_wait);
        }
 }
 
-int zs_startup(struct dec_serial * info)
+static int zs_startup(struct dec_serial * info)
 {
        unsigned long flags;
 
@@ -662,7 +646,7 @@ int zs_startup(struct dec_serial * info)
                        return -ENOMEM;
        }
 
-       save_flags(flags); cli();
+       spin_lock_irqsave(&zs_lock, flags);
 
 #ifdef SERIAL_DEBUG_OPEN
        printk("starting up ttyS%d (irq %d)...", info->line, info->irq);
@@ -718,7 +702,7 @@ int zs_startup(struct dec_serial * info)
        info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
 
        info->flags |= ZILOG_INITIALIZED;
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
        return 0;
 }
 
@@ -738,7 +722,7 @@ static void shutdown(struct dec_serial * info)
               info->irq);
 #endif
 
-       save_flags(flags); cli(); /* Disable interrupts */
+       spin_lock_irqsave(&zs_lock, flags);
 
        if (info->xmit_buf) {
                free_page((unsigned long) info->xmit_buf);
@@ -761,7 +745,7 @@ static void shutdown(struct dec_serial * info)
                set_bit(TTY_IO_ERROR, &info->tty->flags);
 
        info->flags &= ~ZILOG_INITIALIZED;
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
 }
 
 /*
@@ -797,7 +781,7 @@ static void change_speed(struct dec_serial *info)
                        i += 15;
        }
 
-       save_flags(flags); cli();
+       spin_lock_irqsave(&zs_lock, flags);
        info->zs_baud = baud_table[i];
        if (info->zs_baud) {
                brg = BPS_TO_BRG(info->zs_baud, zs_parms->clock/info->clk_divisor);
@@ -870,7 +854,7 @@ static void change_speed(struct dec_serial *info)
        /* Load up the new values */
        load_zsregs(info->zs_channel, info->zs_channel->curregs);
 
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
 }
 
 static void rs_flush_chars(struct tty_struct *tty)
@@ -886,9 +870,9 @@ static void rs_flush_chars(struct tty_struct *tty)
                return;
 
        /* Enable transmitter */
-       save_flags(flags); cli();
+       spin_lock_irqsave(&zs_lock, flags);
        transmit_chars(info);
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
 }
 
 static int rs_write(struct tty_struct * tty,
@@ -904,26 +888,17 @@ static int rs_write(struct tty_struct * tty,
        if (!tty || !info->xmit_buf)
                return 0;
 
-       save_flags(flags);
        while (1) {
-               cli();
+               spin_lock_irqsave(&zs_lock, flags);
                c = min(count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
                                   SERIAL_XMIT_SIZE - info->xmit_head));
                if (c <= 0)
                        break;
 
-               if (from_user) {
-                       down(&tmp_buf_sem);
-                       copy_from_user(tmp_buf, buf, c);
-                       c = min(c, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
-                                      SERIAL_XMIT_SIZE - info->xmit_head));
-                       memcpy(info->xmit_buf + info->xmit_head, tmp_buf, c);
-                       up(&tmp_buf_sem);
-               } else
-                       memcpy(info->xmit_buf + info->xmit_head, buf, c);
+               memcpy(info->xmit_buf + info->xmit_head, buf, c);
                info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
                info->xmit_cnt += c;
-               restore_flags(flags);
+               spin_unlock_irqrestore(&zs_lock, flags);
                buf += c;
                count -= c;
                total += c;
@@ -932,7 +907,7 @@ static int rs_write(struct tty_struct * tty,
        if (info->xmit_cnt && !tty->stopped && !info->tx_stopped
            && !info->tx_active)
                transmit_chars(info);
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
        return total;
 }
 
@@ -964,9 +939,9 @@ static void rs_flush_buffer(struct tty_struct *tty)
 
        if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
                return;
-       cli();
+       spin_lock_irq(&zs_lock);
        info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
-       sti();
+       spin_unlock_irq(&zs_lock);
        tty_wakeup(tty);
 }
 
@@ -994,11 +969,11 @@ static void rs_throttle(struct tty_struct * tty)
                return;
 
        if (I_IXOFF(tty)) {
-               save_flags(flags); cli();
+               spin_lock_irqsave(&zs_lock, flags);
                info->x_char = STOP_CHAR(tty);
                if (!info->tx_active)
                        transmit_chars(info);
-               restore_flags(flags);
+               spin_unlock_irqrestore(&zs_lock, flags);
        }
 
        if (C_CRTSCTS(tty)) {
@@ -1022,7 +997,7 @@ static void rs_unthrottle(struct tty_struct * tty)
                return;
 
        if (I_IXOFF(tty)) {
-               save_flags(flags); cli();
+               spin_lock_irqsave(&zs_lock, flags);
                if (info->x_char)
                        info->x_char = 0;
                else {
@@ -1030,7 +1005,7 @@ static void rs_unthrottle(struct tty_struct * tty)
                        if (!info->tx_active)
                                transmit_chars(info);
                }
-               restore_flags(flags);
+               spin_unlock_irqrestore(&zs_lock, flags);
        }
 
        if (C_CRTSCTS(tty)) {
@@ -1123,9 +1098,9 @@ static int get_lsr_info(struct dec_serial * info, unsigned int *value)
 {
        unsigned char status;
 
-       cli();
+       spin_lock(&zs_lock);
        status = read_zsreg(info->zs_channel, 0);
-       sti();
+       spin_unlock_irq(&zs_lock);
        put_user(status,value);
        return 0;
 }
@@ -1148,11 +1123,11 @@ static int rs_tiocmget(struct tty_struct *tty, struct file *file)
        if (info->zs_channel == info->zs_chan_a)
                result = 0;
        else {
-               cli();
+               spin_lock(&zs_lock);
                control = info->zs_chan_a->curregs[5];
                status_a = read_zsreg(info->zs_chan_a, 0);
                status_b = read_zsreg(info->zs_channel, 0);
-               sti();
+               spin_unlock_irq(&zs_lock);
                result =  ((control  & RTS) ? TIOCM_RTS: 0)
                        | ((control  & DTR) ? TIOCM_DTR: 0)
                        | ((status_b & DCD) ? TIOCM_CAR: 0)
@@ -1167,8 +1142,6 @@ static int rs_tiocmset(struct tty_struct *tty, struct file *file,
                        unsigned int set, unsigned int clear)
 {
        struct dec_serial * info = (struct dec_serial *)tty->driver_data;
-       int error;
-       unsigned int arg, bits;
 
        if (info->hook)
                return -ENODEV;
@@ -1182,8 +1155,7 @@ static int rs_tiocmset(struct tty_struct *tty, struct file *file,
        if (info->zs_channel == info->zs_chan_a)
                return 0;
 
-       get_user(arg, value);
-       cli();
+       spin_lock(&zs_lock);
        if (set & TIOCM_RTS)
                info->zs_chan_a->curregs[5] |= RTS;
        if (set & TIOCM_DTR)
@@ -1193,7 +1165,7 @@ static int rs_tiocmset(struct tty_struct *tty, struct file *file,
        if (clear & TIOCM_DTR)
                info->zs_chan_a->curregs[5] &= ~DTR;
        write_zsreg(info->zs_chan_a, 5, info->zs_chan_a->curregs[5]);
-       sti();
+       spin_unlock_irq(&zs_lock);
        return 0;
 }
 
@@ -1210,19 +1182,18 @@ static void rs_break(struct tty_struct *tty, int break_state)
        if (!info->port)
                return;
 
-       save_flags(flags); cli();
+       spin_lock_irqsave(&zs_lock, flags);
        if (break_state == -1)
                info->zs_channel->curregs[5] |= SND_BRK;
        else
                info->zs_channel->curregs[5] &= ~SND_BRK;
        write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
 }
 
 static int rs_ioctl(struct tty_struct *tty, struct file * file,
                    unsigned int cmd, unsigned long arg)
 {
-       int error;
        struct dec_serial * info = (struct dec_serial *)tty->driver_data;
 
        if (info->hook)
@@ -1299,10 +1270,10 @@ static void rs_close(struct tty_struct *tty, struct file * filp)
        if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
                return;
 
-       save_flags(flags); cli();
+       spin_lock_irqsave(&zs_lock, flags);
 
        if (tty_hung_up_p(filp)) {
-               restore_flags(flags);
+               spin_unlock_irqrestore(&zs_lock, flags);
                return;
        }
 
@@ -1327,7 +1298,7 @@ static void rs_close(struct tty_struct *tty, struct file * filp)
                info->count = 0;
        }
        if (info->count) {
-               restore_flags(flags);
+               spin_unlock_irqrestore(&zs_lock, flags);
                return;
        }
        info->flags |= ZILOG_CLOSING;
@@ -1370,7 +1341,7 @@ static void rs_close(struct tty_struct *tty, struct file * filp)
        }
        info->flags &= ~(ZILOG_NORMAL_ACTIVE|ZILOG_CLOSING);
        wake_up_interruptible(&info->close_wait);
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
 }
 
 /*
@@ -1410,7 +1381,7 @@ static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
 /*
  * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
  */
-void rs_hangup(struct tty_struct *tty)
+static void rs_hangup(struct tty_struct *tty)
 {
        struct dec_serial * info = (struct dec_serial *)tty->driver_data;
 
@@ -1478,16 +1449,16 @@ static int block_til_ready(struct tty_struct *tty, struct file * filp,
        printk("block_til_ready before block: ttyS%d, count = %d\n",
               info->line, info->count);
 #endif
-       cli();
+       spin_lock(&zs_lock);
        if (!tty_hung_up_p(filp))
                info->count--;
-       sti();
+       spin_unlock_irq(&zs_lock);
        info->blocked_open++;
        while (1) {
-               cli();
+               spin_lock(&zs_lock);
                if (tty->termios->c_cflag & CBAUD)
                        zs_rtsdtr(info, RTS | DTR, 1);
-               sti();
+               spin_unlock_irq(&zs_lock);
                set_current_state(TASK_INTERRUPTIBLE);
                if (tty_hung_up_p(filp) ||
                    !(info->flags & ZILOG_INITIALIZED)) {
@@ -1535,7 +1506,7 @@ static int block_til_ready(struct tty_struct *tty, struct file * filp,
  * the IRQ chain.   It also performs the serial-specific
  * initialization for the tty structure.
  */
-int rs_open(struct tty_struct *tty, struct file * filp)
+static int rs_open(struct tty_struct *tty, struct file * filp)
 {
        struct dec_serial       *info;
        int                     retval, line;
@@ -1628,30 +1599,22 @@ static void __init probe_sccs(void)
                return;
        }
 
-       /*
-        * When serial console is activated, tc_init has not been called yet
-        * and system_base is undefined. Unfortunately we have to hardcode
-        * system_base for this case :-(. HK
-        */
        switch(mips_machtype) {
 #ifdef CONFIG_MACH_DECSTATION
        case MACH_DS5000_2X0:
        case MACH_DS5900:
-               system_base = KSEG1ADDR(0x1f800000);
                n_chips = 2;
                zs_parms = &ds_parms;
                zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
                zs_parms->irq1 = dec_interrupt[DEC_IRQ_SCC1];
                break;
        case MACH_DS5000_1XX:
-               system_base = KSEG1ADDR(0x1c000000);
                n_chips = 2;
                zs_parms = &ds_parms;
                zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
                zs_parms->irq1 = dec_interrupt[DEC_IRQ_SCC1];
                break;
        case MACH_DS5000_XX:
-               system_base = KSEG1ADDR(0x1c000000);
                n_chips = 1;
                zs_parms = &ds_parms;
                zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
@@ -1673,17 +1636,17 @@ static void __init probe_sccs(void)
                         * The sccs reside on the high byte of the 16 bit IOBUS
                         */
                        zs_channels[n_channels].control =
-                               (volatile unsigned char *)system_base +
+                               (volatile void *)CKSEG1ADDR(dec_kn_slot_base +
                          (0 == chip ? zs_parms->scc0 : zs_parms->scc1) +
                          (0 == channel ? zs_parms->channel_a_offset :
-                                         zs_parms->channel_b_offset);
+                                         zs_parms->channel_b_offset));
                        zs_channels[n_channels].data =
                                zs_channels[n_channels].control + 4;
 
 #ifndef CONFIG_SERIAL_DEC_CONSOLE
                        /*
                         * We're called early and memory managment isn't up, yet.
-                        * Thus check_region would fail.
+                        * Thus request_region would fail.
                         */
                        if (!request_region((unsigned long)
                                         zs_channels[n_channels].control,
@@ -1726,7 +1689,7 @@ static void __init probe_sccs(void)
                }
        }
 
-       save_and_cli(flags);
+       spin_lock_irqsave(&zs_lock, flags);
        for (n = 0; n < zs_channels_found; n++) {
                if (n % 2 == 0) {
                        write_zsreg(zs_soft[n].zs_chan_a, R9, FHWRES);
@@ -1736,7 +1699,7 @@ static void __init probe_sccs(void)
                load_zsregs(zs_soft[n].zs_channel,
                            zs_soft[n].zs_channel->curregs);
        }
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
 }
 
 static struct tty_operations serial_ops = {
@@ -1769,9 +1732,6 @@ int __init zs_init(void)
        if(!BUS_PRESENT)
                return -ENODEV;
 
-       /* Setup base handler, and timer table. */
-       init_bh(SERIAL_BH, do_serial_bh);
-
        /* Find out how many Z8530 SCCs we have */
        if (zs_chain == 0)
                probe_sccs();
@@ -1820,8 +1780,7 @@ int __init zs_init(void)
                info->event = 0;
                info->count = 0;
                info->blocked_open = 0;
-               info->tqueue.routine = do_softint;
-               info->tqueue.data = info;
+               tasklet_init(&info->tlet, do_softint, (unsigned long)info);
                init_waitqueue_head(&info->open_wait);
                init_waitqueue_head(&info->close_wait);
                printk("ttyS%02d at 0x%08x (irq = %d) is a Z85C30 SCC\n",
@@ -1853,8 +1812,7 @@ int __init zs_init(void)
 /*
  * polling I/O routines
  */
-static int
-zs_poll_tx_char(void *handle, unsigned char ch)
+static int zs_poll_tx_char(void *handle, unsigned char ch)
 {
        struct dec_serial *info = handle;
        struct dec_zschannel *chan = info->zs_channel;
@@ -1877,8 +1835,7 @@ zs_poll_tx_char(void *handle, unsigned char ch)
                return -ENODEV;
 }
 
-static int
-zs_poll_rx_char(void *handle)
+static int zs_poll_rx_char(void *handle)
 {
        struct dec_serial *info = handle;
         struct dec_zschannel *chan = info->zs_channel;
@@ -2057,7 +2014,7 @@ static int __init serial_console_setup(struct console *co, char *options)
        }
        co->cflag = cflag;
 
-       save_and_cli(flags);
+       spin_lock_irqsave(&zs_lock, flags);
 
        /*
         * Set up the baud rate generator.
@@ -2112,7 +2069,7 @@ static int __init serial_console_setup(struct console *co, char *options)
        zs_soft[co->index].clk_divisor = clk_divisor;
        zs_soft[co->index].zs_baud = get_zsbaud(&zs_soft[co->index]);
 
-       restore_flags(flags);
+       spin_unlock_irqrestore(&zs_lock, flags);
 
        return 0;
 }
@@ -2249,5 +2206,3 @@ void __init zs_kgdb_hook(int tty_num)
        set_debug_traps(); /* init stub */
 }
 #endif /* ifdef CONFIG_KGDB */
-
-