linux 2.6.16.38 w/ vs2.0.3-rc1

[linux-2.6.git] / drivers / serial / 68328serial.c

diff --git a/drivers/serial/68328serial.c b/drivers/serial/68328serial.c
index 993a702..7f0f35a 100644 (file)
--- a/drivers/serial/68328serial.c
+++ b/drivers/serial/68328serial.c
@@ -23,6 +23,7 @@
 #include <linux/interrupt.h>
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
+#include <linux/config.h>
 #include <linux/major.h>
 #include <linux/string.h>
 #include <linux/fcntl.h>
@@ -100,6 +101,8 @@ struct tty_driver *serial_driver;
 
 #define RS_ISR_PASS_LIMIT 256
 
+#define _INLINE_ inline
+
 static void change_speed(struct m68k_serial *info);
 
 /*
@@ -130,6 +133,17 @@ static int m68328_console_baud    = CONSOLE_BAUD_RATE;
 static int m68328_console_cbaud   = DEFAULT_CBAUD;
 
 
+/*
+ * tmp_buf is used as a temporary buffer by serial_write.  We need to
+ * lock it in case the memcpy_fromfs 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[SERIAL_XMIT_SIZE]; /* This is cheating */
+
 static inline int serial_paranoia_check(struct m68k_serial *info,
                                        char *name, const char *routine)
 {
@@ -199,16 +213,16 @@ static void rs_stop(struct tty_struct *tty)
        if (serial_paranoia_check(info, tty->name, "rs_stop"))
                return;
        
-       local_irq_save(flags);
+       save_flags(flags); cli();
        uart->ustcnt &= ~USTCNT_TXEN;
-       local_irq_restore(flags);
+       restore_flags(flags);
 }
 
 static void rs_put_char(char ch)
 {
         int flags, loops = 0;
 
-        local_irq_save(flags);
+        save_flags(flags); cli();
 
        while (!(UTX & UTX_TX_AVAIL) && (loops < 1000)) {
                loops++;
@@ -217,7 +231,7 @@ static void rs_put_char(char ch)
 
        UTX_TXDATA = ch;
         udelay(5);
-        local_irq_restore(flags);
+        restore_flags(flags);
 }
 
 static void rs_start(struct tty_struct *tty)
@@ -229,7 +243,7 @@ static void rs_start(struct tty_struct *tty)
        if (serial_paranoia_check(info, tty->name, "rs_start"))
                return;
        
-       local_irq_save(flags);
+       save_flags(flags); cli();
        if (info->xmit_cnt && info->xmit_buf && !(uart->ustcnt & USTCNT_TXEN)) {
 #ifdef USE_INTS
                uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
@@ -237,7 +251,7 @@ static void rs_start(struct tty_struct *tty)
                uart->ustcnt |= USTCNT_TXEN;
 #endif
        }
-       local_irq_restore(flags);
+       restore_flags(flags);
 }
 
 /* Drop into either the boot monitor or kadb upon receiving a break
@@ -248,7 +262,7 @@ static void batten_down_hatches(void)
        /* Drop into the debugger */
 }
 
-static void status_handle(struct m68k_serial *info, unsigned short status)
+static _INLINE_ void status_handle(struct m68k_serial *info, unsigned short status)
 {
 #if 0
        if(status & DCD) {
@@ -275,8 +289,7 @@ static void status_handle(struct m68k_serial *info, unsigned short status)
        return;
 }
 
-static void receive_chars(struct m68k_serial *info, struct pt_regs *regs,
-                         unsigned short rx)
+static _INLINE_ void receive_chars(struct m68k_serial *info, struct pt_regs *regs, unsigned short rx)
 {
        struct tty_struct *tty = info->tty;
        m68328_uart *uart = &uart_addr[info->line];
@@ -315,6 +328,14 @@ static void receive_chars(struct m68k_serial *info, struct pt_regs *regs,
                if(!tty)
                        goto clear_and_exit;
                
+               /*
+                * Make sure that we do not overflow the buffer
+                */
+               if (tty_request_buffer_room(tty, 1) == 0) {
+                       tty_schedule_flip(tty);
+                       return;
+               }
+
                flag = TTY_NORMAL;
 
                if(rx & URX_PARITY_ERROR) {
@@ -338,7 +359,7 @@ clear_and_exit:
        return;
 }
 
-static void transmit_chars(struct m68k_serial *info)
+static _INLINE_ void transmit_chars(struct m68k_serial *info)
 {
        m68328_uart *uart = &uart_addr[info->line];
 
@@ -453,7 +474,7 @@ static int startup(struct m68k_serial * info)
                        return -ENOMEM;
        }
 
-       local_irq_save(flags);
+       save_flags(flags); cli();
 
        /*
         * Clear the FIFO buffers and disable them
@@ -486,7 +507,7 @@ static int startup(struct m68k_serial * info)
        change_speed(info);
 
        info->flags |= S_INITIALIZED;
-       local_irq_restore(flags);
+       restore_flags(flags);
        return 0;
 }
 
@@ -503,7 +524,7 @@ static void shutdown(struct m68k_serial * info)
        if (!(info->flags & S_INITIALIZED))
                return;
 
-       local_irq_save(flags);
+       save_flags(flags); cli(); /* Disable interrupts */
        
        if (info->xmit_buf) {
                free_page((unsigned long) info->xmit_buf);
@@ -514,7 +535,7 @@ static void shutdown(struct m68k_serial * info)
                set_bit(TTY_IO_ERROR, &info->tty->flags);
        
        info->flags &= ~S_INITIALIZED;
-       local_irq_restore(flags);
+       restore_flags(flags);
 }
 
 struct {
@@ -635,24 +656,24 @@ static void rs_fair_output(void)
        if (info == 0) return;
        if (info->xmit_buf == 0) return;
 
-       local_irq_save(flags);
+       save_flags(flags);  cli();
        left = info->xmit_cnt;
        while (left != 0) {
                c = info->xmit_buf[info->xmit_tail];
                info->xmit_tail = (info->xmit_tail+1) & (SERIAL_XMIT_SIZE-1);
                info->xmit_cnt--;
-               local_irq_restore(flags);
+               restore_flags(flags);
 
                rs_put_char(c);
 
-               local_irq_save(flags);
+               save_flags(flags);  cli();
                left = min(info->xmit_cnt, left-1);
        }
 
        /* Last character is being transmitted now (hopefully). */
        udelay(5);
 
-       local_irq_restore(flags);
+       restore_flags(flags);
        return;
 }
 
@@ -700,11 +721,11 @@ static void rs_flush_chars(struct tty_struct *tty)
 #endif
 
        /* Enable transmitter */
-       local_irq_save(flags);
+       save_flags(flags); cli();
 
        if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
                        !info->xmit_buf) {
-               local_irq_restore(flags);
+               restore_flags(flags);
                return;
        }
 
@@ -729,7 +750,7 @@ static void rs_flush_chars(struct tty_struct *tty)
        while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
        }
 #endif
-       local_irq_restore(flags);
+       restore_flags(flags);
 }
 
 extern void console_printn(const char * b, int count);
@@ -748,22 +769,18 @@ static int rs_write(struct tty_struct * tty,
        if (!tty || !info->xmit_buf)
                return 0;
 
-       local_save_flags(flags);
+       save_flags(flags);
        while (1) {
-               local_irq_disable();            
+               cli();          
                c = min_t(int, count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
                                   SERIAL_XMIT_SIZE - info->xmit_head));
-               local_irq_restore(flags);
-
                if (c <= 0)
                        break;
 
                memcpy(info->xmit_buf + info->xmit_head, buf, c);
-
-               local_irq_disable();
                info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
                info->xmit_cnt += c;
-               local_irq_restore(flags);
+               restore_flags(flags);
                buf += c;
                count -= c;
                total += c;
@@ -771,7 +788,7 @@ static int rs_write(struct tty_struct * tty,
 
        if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped) {
                /* Enable transmitter */
-               local_irq_disable();            
+               cli();          
 #ifndef USE_INTS
                while(info->xmit_cnt) {
 #endif
@@ -791,9 +808,9 @@ static int rs_write(struct tty_struct * tty,
 #ifndef USE_INTS
                }
 #endif
-               local_irq_restore(flags);
+               restore_flags(flags);
        }
-
+       restore_flags(flags);
        return total;
 }
 
@@ -822,13 +839,12 @@ static int rs_chars_in_buffer(struct tty_struct *tty)
 static void rs_flush_buffer(struct tty_struct *tty)
 {
        struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
-       unsigned long flags;
                                
        if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
                return;
-       local_irq_save(flags);
+       cli();
        info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
-       local_irq_restore(flags);
+       sti();
        tty_wakeup(tty);
 }
 
@@ -958,15 +974,14 @@ static int get_lsr_info(struct m68k_serial * info, unsigned int *value)
        m68328_uart *uart = &uart_addr[info->line];
 #endif
        unsigned char status;
-       unsigned long flags;
 
-       local_irq_save(flags);
+       cli();
 #ifdef CONFIG_SERIAL_68328_RTS_CTS
        status = (uart->utx.w & UTX_CTS_STAT) ? 1 : 0;
 #else
        status = 0;
 #endif
-       local_irq_restore(flags);
+       sti();
        put_user(status,value);
        return 0;
 }
@@ -980,13 +995,14 @@ static void send_break(struct m68k_serial * info, unsigned int duration)
         unsigned long flags;
         if (!info->port)
                 return;
-        local_irq_save(flags);
+        save_flags(flags);
+        cli();
 #ifdef USE_INTS        
        uart->utx.w |= UTX_SEND_BREAK;
        msleep_interruptible(duration);
        uart->utx.w &= ~UTX_SEND_BREAK;
 #endif         
-        local_irq_restore(flags);
+        restore_flags(flags);
 }
 
 static int rs_ioctl(struct tty_struct *tty, struct file * file,
@@ -1045,7 +1061,7 @@ static int rs_ioctl(struct tty_struct *tty, struct file * file,
                                               (struct serial_struct *) arg);
                case TIOCSERGETLSR: /* Get line status register */
                        if (access_ok(VERIFY_WRITE, (void *) arg,
-                                               sizeof(unsigned int)))
+                                               sizeof(unsigned int));
                                return get_lsr_info(info, (unsigned int *) arg);
                        return -EFAULT;
                case TIOCSERGSTRUCT:
@@ -1098,10 +1114,10 @@ static void rs_close(struct tty_struct *tty, struct file * filp)
        if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
                return;
        
-       local_irq_save(flags);
+       save_flags(flags); cli();
        
        if (tty_hung_up_p(filp)) {
-               local_irq_restore(flags);
+               restore_flags(flags);
                return;
        }
        
@@ -1123,7 +1139,7 @@ static void rs_close(struct tty_struct *tty, struct file * filp)
                info->count = 0;
        }
        if (info->count) {
-               local_irq_restore(flags);
+               restore_flags(flags);
                return;
        }
        info->flags |= S_CLOSING;
@@ -1171,7 +1187,7 @@ static void rs_close(struct tty_struct *tty, struct file * filp)
        }
        info->flags &= ~(S_NORMAL_ACTIVE|S_CLOSING);
        wake_up_interruptible(&info->close_wait);
-       local_irq_restore(flags);
+       restore_flags(flags);
 }
 
 /*
@@ -1247,9 +1263,9 @@ static int block_til_ready(struct tty_struct *tty, struct file * filp,
        info->count--;
        info->blocked_open++;
        while (1) {
-               local_irq_disable();
+               cli();
                m68k_rtsdtr(info, 1);
-               local_irq_enable();
+               sti();
                current->state = TASK_INTERRUPTIBLE;
                if (tty_hung_up_p(filp) ||
                    !(info->flags & S_INITIALIZED)) {
@@ -1429,7 +1445,7 @@ rs68328_init(void)
                return -ENOMEM;
        }
 
-       local_irq_save(flags);
+       save_flags(flags); cli();
 
        for(i=0;i<NR_PORTS;i++) {
 
@@ -1474,7 +1490,7 @@ rs68328_init(void)
                    serial_pm[i]->data = info;
 #endif
        }
-       local_irq_restore(flags);
+       restore_flags(flags);
        return 0;
 }