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[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [drivers/] [char/] [vac-serial.c] - Blame information for rev 1765

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/*
 * vacserial.c: VAC UART serial driver
 *              This code stealed and adopted from linux/drivers/char/serial.c
 *              See that for author info
 *
 * Copyright (C) 1998 Gleb Raiko & Vladimir Roganov
 */
 
#undef  SERIAL_PARANOIA_CHECK
#define CONFIG_SERIAL_NOPAUSE_IO
#define SERIAL_DO_RESTART
 
#ifndef CONFIG_SERIAL_SHARE_IRQ
#define CONFIG_SERIAL_SHARE_IRQ
#endif
 
/* Set of debugging defines */
 
#undef  SERIAL_DEBUG_INTR
#undef  SERIAL_DEBUG_OPEN
#undef  SERIAL_DEBUG_FLOW
#undef  SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
 
#define RS_STROBE_TIME (10*HZ)
#define RS_ISR_PASS_LIMIT  2 /* Beget is not a super-computer (old=256) */
 
#define IRQ_T(state) \
 ((state->flags & ASYNC_SHARE_IRQ) ? SA_SHIRQ : SA_INTERRUPT)
 
#define SERIAL_INLINE
 
#if defined(MODULE) && defined(SERIAL_DEBUG_MCOUNT)
#define DBG_CNT(s) baget_printk("(%s):[%x] refc=%d, serc=%d, ttyc=%d-> %s\n", \
  kdevname(tty->device),(info->flags),serial_refcount,info->count,tty->count,s)
#else
#define DBG_CNT(s)
#endif
 
#define  QUAD_UART_SPEED  /* Useful for Baget */
 
/*
 * End of serial driver configuration section.
 */
 
#include <linux/config.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/delay.h>
#ifdef CONFIG_SERIAL_CONSOLE
#include <linux/console.h>
#endif
 
#include <asm/system.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <asm/bitops.h>
#include <asm/serial.h>
#include <asm/baget/baget.h>
 
#define BAGET_VAC_UART_IRQ 0x35
 
/*
 *  Implementation note:
 *  It was descovered by means of advanced electronic tools,
 *  if the driver works via TX_READY interrupts then VIC generates
 *  strange self-eliminating traps. Thus, the driver is rewritten to work
 *  via TX_EMPTY
 */
 
/* VAC-specific check/debug switches */
 
#undef CHECK_REG_INDEX
#undef DEBUG_IO_PORT_A
 
#ifdef SERIAL_INLINE
#define _INLINE_ inline
#endif
 
static char *serial_name = "VAC Serial driver";
static char *serial_version = "4.26";
 
static DECLARE_TASK_QUEUE(tq_serial);
 
static struct tty_driver serial_driver, callout_driver;
static int serial_refcount;
 
/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS 256
 
/*
 * IRQ_timeout          - How long the timeout should be for each IRQ
 *                              should be after the IRQ has been active.
 */
 
static struct async_struct *IRQ_ports[NR_IRQS];
static int IRQ_timeout[NR_IRQS];
#ifdef CONFIG_SERIAL_CONSOLE
static struct console sercons;
#endif
 
static void autoconfig(struct serial_state * info);
static void change_speed(struct async_struct *info);
static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
static void rs_timer(unsigned long dummy);
 
static struct timer_list vacs_timer;
 
/*
 * Here we define the default xmit fifo size used for each type of
 * UART
 */
static struct serial_uart_config uart_config[] = {
        { "unknown",  1, 0 },  /* Must go first  --  used as unasigned */
        { "VAC UART", 1, 0 }
};
#define VAC_UART_TYPE 1   /* Just index in above array */
 
static struct serial_state rs_table[] = {
/*
 * VAC has tricky layout for pair of his SIO registers,
 *  so we need special function to access ones.
 *  To identify port we use their TX offset
 */
        { 0, 9600, VAC_UART_B_TX, BAGET_VAC_UART_IRQ,
          STD_COM_FLAGS }, /* VAC UART B */
        { 0, 9600, VAC_UART_A_TX, BAGET_VAC_UART_IRQ,
          STD_COM_FLAGS }  /* VAC UART A */
};
 
#define NR_PORTS        (sizeof(rs_table)/sizeof(struct serial_state))
 
static struct tty_struct *serial_table[NR_PORTS];
static struct termios *serial_termios[NR_PORTS];
static struct termios *serial_termios_locked[NR_PORTS];
 
#ifndef MIN
#define MIN(a,b)        ((a) < (b) ? (a) : (b))
#endif
 
/*
 * 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;
static DECLARE_MUTEX(tmp_buf_sem);
 
static inline int serial_paranoia_check(struct async_struct *info,
                                        kdev_t device, const char *routine)
{
#ifdef SERIAL_PARANOIA_CHECK
        static const char *badmagic =
                "Warning: bad magic number for serial struct (%s) in %s\n";
        static const char *badinfo =
                "Warning: null async_struct for (%s) in %s\n";
 
        if (!info) {
                printk(badinfo, kdevname(device), routine);
                return 1;
        }
        if (info->magic != SERIAL_MAGIC) {
                printk(badmagic, kdevname(device), routine);
                return 1;
        }
#endif
        return 0;
}
 
/*
  To unify UART A/B access we will use following function
  to compute register offsets by register index.
 */
 
#define VAC_UART_MODE       0
#define VAC_UART_TX         1
#define VAC_UART_RX         2
#define VAC_UART_INT_MASK   3
#define VAC_UART_INT_STATUS 4
 
#define VAC_UART_REG_NR     5
 
static inline int uart_offset_map(unsigned long port, int reg_index)
{
        static const unsigned int ind_to_reg[VAC_UART_REG_NR][NR_PORTS] = {
                { VAC_UART_B_MODE,       VAC_UART_A_MODE       },
                { VAC_UART_B_TX,         VAC_UART_A_TX         },
                { VAC_UART_B_RX,         VAC_UART_A_RX         },
                { VAC_UART_B_INT_MASK,   VAC_UART_A_INT_MASK   },
                { VAC_UART_B_INT_STATUS, VAC_UART_A_INT_STATUS }
        };
#ifdef CHECK_REG_INDEX
        if (reg_index > VAC_UART_REG_NR) panic("vacserial: bad reg_index");
#endif
        return ind_to_reg[reg_index][port == VAC_UART_B_TX ? 0 : 1];
}
 
static inline unsigned int serial_inw(struct async_struct *info, int offset)
{
        int val = vac_inw(uart_offset_map(info->port,offset));
#ifdef DEBUG_IO_PORT_A
        if (info->port == VAC_UART_A_TX)
                printk("UART_A_IN: reg = 0x%04x, val = 0x%04x\n",
                       uart_offset_map(info->port,offset), val);
#endif
        return val;
}
 
static inline unsigned int serial_inp(struct async_struct *info, int offset)
{
        return serial_inw(info, offset);
}
 
static inline unsigned int serial_in(struct async_struct *info, int offset)
{
        return serial_inw(info, offset);
}
 
static inline void serial_outw(struct async_struct *info,int offset, int value)
{
#ifdef DEBUG_IO_PORT_A
        if (info->port == VAC_UART_A_TX)
                printk("UART_A_OUT: offset = 0x%04x, val = 0x%04x\n",
                       uart_offset_map(info->port,offset), value);
#endif
        vac_outw(value, uart_offset_map(info->port,offset));
}
 
static inline void serial_outp(struct async_struct *info,int offset, int value)
{
        serial_outw(info,offset,value);
}
 
static inline void serial_out(struct async_struct *info,int offset, int value)
{
        serial_outw(info,offset,value);
}
 
/*
 * ------------------------------------------------------------
 * rs_stop() and rs_start()
 *
 * This routines are called before setting or resetting tty->stopped.
 * They enable or disable transmitter interrupts, as necessary.
 * ------------------------------------------------------------
 */
static void rs_stop(struct tty_struct *tty)
{
        struct async_struct *info = (struct async_struct *)tty->driver_data;
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_stop"))
                return;
 
        save_flags(flags); cli();
        if (info->IER & VAC_UART_INT_TX_EMPTY) {
                info->IER &= ~VAC_UART_INT_TX_EMPTY;
                serial_out(info, VAC_UART_INT_MASK, info->IER);
        }
        restore_flags(flags);
}
 
static void rs_start(struct tty_struct *tty)
{
        struct async_struct *info = (struct async_struct *)tty->driver_data;
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_start"))
                return;
 
        save_flags(flags); cli();
        if (info->xmit_cnt && info->xmit_buf
            && !(info->IER & VAC_UART_INT_TX_EMPTY)) {
                info->IER |= VAC_UART_INT_TX_EMPTY;
                serial_out(info, VAC_UART_INT_MASK, info->IER);
        }
        restore_flags(flags);
}
 
/*
 * ----------------------------------------------------------------------
 *
 * Here starts the interrupt handling routines.  All of the following
 * subroutines are declared as inline and are folded into
 * rs_interrupt().  They were separated out for readability's sake.
 *
 * Note: rs_interrupt() is a "fast" interrupt, which means that it
 * runs with interrupts turned off.  People who may want to modify
 * rs_interrupt() should try to keep the interrupt handler as fast as
 * possible.  After you are done making modifications, it is not a bad
 * idea to do:
 *
 * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
 *
 * and look at the resulting assemble code in serial.s.
 *
 *                              - Ted Ts'o (tytso@mit.edu), 7-Mar-93
 * -----------------------------------------------------------------------
 */
 
/*
 * 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 async_struct *info,
                                  int event)
{
        info->event |= 1 << event;
        queue_task(&info->tqueue, &tq_serial);
        mark_bh(SERIAL_BH);
}
 
static _INLINE_ void receive_chars(struct async_struct *info,
                                   int *status)
{
        struct tty_struct *tty = info->tty;
        unsigned short rx;
        unsigned char ch;
        int ignored = 0;
        struct  async_icount *icount;
 
        icount = &info->state->icount;
        do {
                rx = serial_inw(info, VAC_UART_RX);
                ch = VAC_UART_RX_DATA_MASK & rx;
 
                if (tty->flip.count >= TTY_FLIPBUF_SIZE)
                        break;
                *tty->flip.char_buf_ptr = ch;
                icount->rx++;
 
#ifdef SERIAL_DEBUG_INTR
                baget_printk("DR%02x:%02x...", rx, *status);
#endif
                *tty->flip.flag_buf_ptr = 0;
                if (*status & (VAC_UART_STATUS_RX_BREAK_CHANGE
                               | VAC_UART_STATUS_RX_ERR_PARITY
                               | VAC_UART_STATUS_RX_ERR_FRAME
                               | VAC_UART_STATUS_RX_ERR_OVERRUN)) {
                        /*
                         * For statistics only
                         */
                        if (*status & VAC_UART_STATUS_RX_BREAK_CHANGE) {
                                *status &= ~(VAC_UART_STATUS_RX_ERR_FRAME
                                             | VAC_UART_STATUS_RX_ERR_PARITY);
                                icount->brk++;
                        } else if (*status & VAC_UART_STATUS_RX_ERR_PARITY)
                                icount->parity++;
                        else if (*status & VAC_UART_STATUS_RX_ERR_FRAME)
                                icount->frame++;
                        if (*status & VAC_UART_STATUS_RX_ERR_OVERRUN)
                                icount->overrun++;
 
                        /*
                         * Now check to see if character should be
                         * ignored, and mask off conditions which
                         * should be ignored.
                         */
                        if (*status & info->ignore_status_mask) {
                                if (++ignored > 100)
                                        break;
                                goto ignore_char;
                        }
                        *status &= info->read_status_mask;
 
                        if (*status & (VAC_UART_STATUS_RX_BREAK_CHANGE)) {
#ifdef SERIAL_DEBUG_INTR
                                baget_printk("handling break....");
#endif
                                *tty->flip.flag_buf_ptr = TTY_BREAK;
                                if (info->flags & ASYNC_SAK)
                                        do_SAK(tty);
                        } else if (*status & VAC_UART_STATUS_RX_ERR_PARITY)
                                *tty->flip.flag_buf_ptr = TTY_PARITY;
                        else if (*status & VAC_UART_STATUS_RX_ERR_FRAME)
                                *tty->flip.flag_buf_ptr = TTY_FRAME;
                        if (*status & VAC_UART_STATUS_RX_ERR_OVERRUN) {
                                /*
                                 * Overrun is special, since it's
                                 * reported immediately, and doesn't
                                 * affect the current character
                                 */
                                if (tty->flip.count < TTY_FLIPBUF_SIZE) {
                                        tty->flip.count++;
                                        tty->flip.flag_buf_ptr++;
                                        tty->flip.char_buf_ptr++;
                                        *tty->flip.flag_buf_ptr = TTY_OVERRUN;
                                }
                        }
                }
                tty->flip.flag_buf_ptr++;
                tty->flip.char_buf_ptr++;
                tty->flip.count++;
        ignore_char:
                *status = serial_inw(info, VAC_UART_INT_STATUS);
        } while ((*status & VAC_UART_STATUS_RX_READY));
        tty_flip_buffer_push(tty);
}
 
static _INLINE_ void transmit_chars(struct async_struct *info, int *intr_done)
{
        int count;
 
        if (info->x_char) {
                serial_outw(info, VAC_UART_TX,
                            (((unsigned short)info->x_char)<<8));
                info->state->icount.tx++;
                info->x_char = 0;
                if (intr_done)
                        *intr_done = 0;
                return;
        }
        if ((info->xmit_cnt <= 0) || info->tty->stopped ||
            info->tty->hw_stopped) {
                info->IER &= ~VAC_UART_INT_TX_EMPTY;
                serial_outw(info, VAC_UART_INT_MASK, info->IER);
                return;
        }
        count = info->xmit_fifo_size;
        do {
                serial_out(info, VAC_UART_TX,
                           (unsigned short)info->xmit_buf[info->xmit_tail++] \
                           << 8);
                info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
                info->state->icount.tx++;
                if (--info->xmit_cnt <= 0)
                        break;
        } while (--count > 0);
 
        if (info->xmit_cnt < WAKEUP_CHARS)
                rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
 
#ifdef SERIAL_DEBUG_INTR
        baget_printk("THRE...");
#endif
        if (intr_done)
                *intr_done = 0;
 
        if (info->xmit_cnt <= 0) {
                info->IER &= ~VAC_UART_INT_TX_EMPTY;
                serial_outw(info, VAC_UART_INT_MASK, info->IER);
        }
}
 
static _INLINE_ void check_modem_status(struct async_struct *info)
{
#if 0 /* VAC hasn't modem control */
        wake_up_interruptible(&info->open_wait);
        rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
#endif
}
 
#ifdef CONFIG_SERIAL_SHARE_IRQ
 
 
/*
 *  Specific functions needed for VAC UART interrupt enter/leave
 */
 
#define VAC_INT_CTRL_UART_ENABLE  \
   (VAC_INT_CTRL_TIMER_PIO10|VAC_INT_CTRL_UART_B_PIO7|VAC_INT_CTRL_UART_A_PIO7)
 
#define VAC_INT_CTRL_UART_DISABLE(info) \
   (VAC_INT_CTRL_TIMER_PIO10 | \
    ((info->port == VAC_UART_A_TX) ? \
     (VAC_INT_CTRL_UART_A_DISABLE|VAC_INT_CTRL_UART_B_PIO7) : \
     (VAC_INT_CTRL_UART_A_PIO7|VAC_INT_CTRL_UART_B_DISABLE)))
 
/*
 *  Following two functions were proposed by Pavel Osipenko
 *  to make VAC/VIC behaviour more regular.
 */
static void intr_begin(struct async_struct* info)
{
        serial_outw(info, VAC_UART_INT_MASK, 0);
}
 
static void intr_end(struct async_struct* info)
{
        vac_outw(VAC_INT_CTRL_UART_DISABLE(info), VAC_INT_CTRL);
        vac_outw(VAC_INT_CTRL_UART_ENABLE,        VAC_INT_CTRL);
 
        serial_outw(info, VAC_UART_INT_MASK, info->IER);
}
 
/*
 * This is the serial driver's generic interrupt routine
 */
static void rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
{
        int status;
        struct async_struct * info;
        int pass_counter = 0;
        struct async_struct *end_mark = 0;
 
#ifdef SERIAL_DEBUG_INTR
        baget_printk("rs_interrupt(%d)...", irq);
#endif
 
        info = IRQ_ports[irq];
        if (!info)
                return;
 
        do {
                intr_begin(info);  /* Mark we begin port handling */
 
                if (!info->tty ||
                     (serial_inw (info, VAC_UART_INT_STATUS)
                      & VAC_UART_STATUS_INTS) == 0)
                    {
                        if (!end_mark)
                                end_mark = info;
                        goto next;
                    }
                end_mark = 0;
 
                info->last_active = jiffies;
 
                status = serial_inw(info, VAC_UART_INT_STATUS);
#ifdef SERIAL_DEBUG_INTR
                baget_printk("status = %x...", status);
#endif
                if (status & VAC_UART_STATUS_RX_READY) {
                        receive_chars(info, &status);
                }
                check_modem_status(info);
                if (status & VAC_UART_STATUS_TX_EMPTY)
                        transmit_chars(info, 0);
 
        next:
                intr_end(info);   /* Mark this port handled */
 
                info = info->next_port;
                if (!info) {
                        info = IRQ_ports[irq];
                        if (pass_counter++ > RS_ISR_PASS_LIMIT) {
                                break;  /* Prevent infinite loops */
                        }
                        continue;
                }
        } while (end_mark != info);
#ifdef SERIAL_DEBUG_INTR
        baget_printk("end.\n");
#endif
 
 
}
#endif /* #ifdef CONFIG_SERIAL_SHARE_IRQ */
 
 
/* The original driver was simplified here:
   two functions were joined to reduce code */
 
#define rs_interrupt_single rs_interrupt
 
 
/*
 * -------------------------------------------------------------------
 * Here ends the serial interrupt routines.
 * -------------------------------------------------------------------
 */
 
/*
 * This routine is used to handle the "bottom half" processing for the
 * serial driver, known also the "software interrupt" processing.
 * This processing is done at the kernel interrupt level, after the
 * rs_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON.  This
 * is where time-consuming activities which can not be done in the
 * 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_serial);
}
 
static void do_softint(void *private_)
{
        struct async_struct     *info = (struct async_struct *) private_;
        struct tty_struct       *tty;
 
        tty = info->tty;
        if (!tty)
                return;
 
        if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
                if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
                    tty->ldisc.write_wakeup)
                        (tty->ldisc.write_wakeup)(tty);
                wake_up_interruptible(&tty->write_wait);
        }
}
 
/*
 * ---------------------------------------------------------------
 * Low level utility subroutines for the serial driver:  routines to
 * figure out the appropriate timeout for an interrupt chain, routines
 * to initialize and startup a serial port, and routines to shutdown a
 * serial port.  Useful stuff like that.
 * ---------------------------------------------------------------
 */
 
/*
 * This routine figures out the correct timeout for a particular IRQ.
 * It uses the smallest timeout of all of the serial ports in a
 * particular interrupt chain.  Now only used for IRQ 0....
 */
static void figure_IRQ_timeout(int irq)
{
        struct  async_struct    *info;
        int     timeout = 60*HZ;        /* 60 seconds === a long time :-) */
 
        info = IRQ_ports[irq];
        if (!info) {
                IRQ_timeout[irq] = 60*HZ;
                return;
        }
        while (info) {
                if (info->timeout < timeout)
                        timeout = info->timeout;
                info = info->next_port;
        }
        if (!irq)
                timeout = timeout / 2;
        IRQ_timeout[irq] = timeout ? timeout : 1;
}
 
static int startup(struct async_struct * info)
{
        unsigned long flags;
        int     retval=0;
        void (*handler)(int, void *, struct pt_regs *);
        struct serial_state *state= info->state;
        unsigned long page;
 
        page = get_free_page(GFP_KERNEL);
        if (!page)
                return -ENOMEM;
 
        save_flags(flags); cli();
 
        if (info->flags & ASYNC_INITIALIZED) {
                free_page(page);
                goto errout;
        }
        if (!state->port || !state->type) {
                if (info->tty)
                        set_bit(TTY_IO_ERROR, &info->tty->flags);
                free_page(page);
                goto errout;
        }
        if (info->xmit_buf)
                free_page(page);
        else
                info->xmit_buf = (unsigned char *) page;
 
#ifdef SERIAL_DEBUG_OPEN
        baget_printk("starting up ttys%d (irq %d)...", info->line, state->irq);
#endif
 
        if (uart_config[info->state->type].flags & UART_STARTECH) {
                /* Wake up UART */
                serial_outp(info, VAC_UART_MODE, 0);
                serial_outp(info, VAC_UART_INT_MASK, 0);
        }
 
        /*
         * Allocate the IRQ if necessary
         */
        if (state->irq && (!IRQ_ports[state->irq] ||
                          !IRQ_ports[state->irq]->next_port)) {
 
                if (IRQ_ports[state->irq]) {
#ifdef CONFIG_SERIAL_SHARE_IRQ
                        free_irq(state->irq, NULL);
                                handler = rs_interrupt;
#else
                        retval = -EBUSY;
                        goto errout;
#endif /* CONFIG_SERIAL_SHARE_IRQ */
                } else
                        handler = rs_interrupt_single;
 
 
                retval = request_irq(state->irq, handler, IRQ_T(state),
                                     "serial", NULL);
                if (retval) {
                        if (capable(CAP_SYS_ADMIN)) {
                                if (info->tty)
                                        set_bit(TTY_IO_ERROR,
                                                &info->tty->flags);
                                retval = 0;
                        }
                        goto errout;
                }
        }
 
        /*
         * Insert serial port into IRQ chain.
         */
        info->prev_port = 0;
        info->next_port = IRQ_ports[state->irq];
        if (info->next_port)
                info->next_port->prev_port = info;
        IRQ_ports[state->irq] = info;
        figure_IRQ_timeout(state->irq);
 
        /*
         * Clear the interrupt registers.
         */
     /* (void) serial_inw(info, VAC_UART_INT_STATUS); */   /* (see above) */
        (void) serial_inw(info, VAC_UART_RX);
 
        /*
         * Now, initialize the UART
         */
        serial_outp(info, VAC_UART_MODE, VAC_UART_MODE_INITIAL); /*reset DLAB*/
 
        /*
         * Finally, enable interrupts
         */
        info->IER = VAC_UART_INT_RX_BREAK_CHANGE | VAC_UART_INT_RX_ERRS | \
                        VAC_UART_INT_RX_READY;
        serial_outp(info, VAC_UART_INT_MASK, info->IER); /*enable interrupts*/
 
        /*
         * And clear the interrupt registers again for luck.
         */
        (void)serial_inp(info, VAC_UART_INT_STATUS);
        (void)serial_inp(info, VAC_UART_RX);
 
        if (info->tty)
                clear_bit(TTY_IO_ERROR, &info->tty->flags);
        info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
 
        /*
         * Set up serial timers...
         */
        mod_timer(&vacs_timer, jiffies + 2*HZ/100);
 
        /*
         * and set the speed of the serial port
         */
        change_speed(info);
 
        info->flags |= ASYNC_INITIALIZED;
        restore_flags(flags);
        return 0;
 
errout:
        restore_flags(flags);
        return retval;
}
 
/*
 * This routine will shutdown a serial port; interrupts are disabled, and
 * DTR is dropped if the hangup on close termio flag is on.
 */
static void shutdown(struct async_struct * info)
{
        unsigned long   flags;
        struct serial_state *state;
        int             retval;
 
        if (!(info->flags & ASYNC_INITIALIZED))
                return;
 
        state = info->state;
 
#ifdef SERIAL_DEBUG_OPEN
        baget_printk("Shutting down serial port %d (irq %d)....", info->line,
               state->irq);
#endif
 
        save_flags(flags); cli(); /* Disable interrupts */
 
        /*
         * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
         * here so the queue might never be waken up
         */
        wake_up_interruptible(&info->delta_msr_wait);
 
        /*
         * First unlink the serial port from the IRQ chain...
         */
        if (info->next_port)
                info->next_port->prev_port = info->prev_port;
        if (info->prev_port)
                info->prev_port->next_port = info->next_port;
        else
                IRQ_ports[state->irq] = info->next_port;
        figure_IRQ_timeout(state->irq);
 
        /*
         * Free the IRQ, if necessary
         */
        if (state->irq && (!IRQ_ports[state->irq] ||
                          !IRQ_ports[state->irq]->next_port)) {
                if (IRQ_ports[state->irq]) {
                        free_irq(state->irq, NULL);
                        retval = request_irq(state->irq, rs_interrupt_single,
                                             IRQ_T(state), "serial", NULL);
 
                        if (retval)
                                printk("serial shutdown: request_irq: error %d"
                                       "  Couldn't reacquire IRQ.\n", retval);
                } else
                        free_irq(state->irq, NULL);
        }
 
        if (info->xmit_buf) {
                free_page((unsigned long) info->xmit_buf);
                info->xmit_buf = 0;
        }
 
        info->IER = 0;
        serial_outp(info, VAC_UART_INT_MASK, 0x00);     /* disable all intrs */
 
        /* disable break condition */
        serial_out(info, VAC_UART_MODE, serial_inp(info, VAC_UART_MODE) & \
                   ~VAC_UART_MODE_SEND_BREAK);
 
        if (info->tty)
                set_bit(TTY_IO_ERROR, &info->tty->flags);
 
        info->flags &= ~ASYNC_INITIALIZED;
        restore_flags(flags);
}
 
/*
 *  When we set line mode, we call this function
 *  for Baget-specific adjustments.
 */
 
static inline unsigned short vac_uart_mode_fixup (unsigned short cval)
{
#ifdef QUAD_UART_SPEED
        /*
         *  When we are using 4-x advantage in speed:
         *
         *  Disadvantage : can't support 75, 150 bauds
         *  Advantage    : can support 19200, 38400 bauds
         */
        char speed = 7 & (cval >> 10);
        cval &= ~(7 << 10);
        cval |= VAC_UART_MODE_BAUD(speed-2);
#endif
 
        /*
         *  In general, we have Tx and Rx ON all time
         *  and use int mask flag for their disabling.
         */
        cval |= VAC_UART_MODE_RX_ENABLE;
        cval |= VAC_UART_MODE_TX_ENABLE;
        cval |= VAC_UART_MODE_CHAR_RX_ENABLE;
        cval |= VAC_UART_MODE_CHAR_TX_ENABLE;
 
        /* Low 4 bits are not used in UART */
        cval &= ~0xf;
 
        return cval;
}
 
/*
 * This routine is called to set the UART divisor registers to match
 * the specified baud rate for a serial port.
 */
static void change_speed(struct async_struct *info)
{
        unsigned short port;
        int     quot = 0, baud_base, baud;
        unsigned cflag, cval;
        int     bits;
        unsigned long   flags;
 
        if (!info->tty || !info->tty->termios)
                return;
        cflag = info->tty->termios->c_cflag;
        if (!(port = info->port))
                return;
 
        /* byte size and parity */
        switch (cflag & CSIZE) {
              case CS7: cval = 0x0;  bits = 9; break;
              case CS8: cval = VAC_UART_MODE_8BIT_CHAR; bits = 10; break;
              /* Never happens, but GCC is too dumb to figure it out */
              case CS5:
              case CS6:
              default:  cval = 0x0; bits = 9; break;
              }
        cval &= ~VAC_UART_MODE_PARITY_ENABLE;
        if (cflag & PARENB) {
                cval |= VAC_UART_MODE_PARITY_ENABLE;
                bits++;
        }
        if (cflag & PARODD)
                cval |= VAC_UART_MODE_PARITY_ODD;
 
        /* Determine divisor based on baud rate */
        baud = tty_get_baud_rate(info->tty);
        if (!baud)
                baud = 9600;    /* B0 transition handled in rs_set_termios */
        baud_base = info->state->baud_base;
        if (baud == 38400 &&
            ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
                quot = info->state->custom_divisor;
        else {
                if (baud == 134)
                        /* Special case since 134 is really 134.5 */
                        quot = (2*baud_base / 269);
                else if (baud)
                        quot = baud_base / baud;
        }
        /* If the quotient is ever zero, default to 9600 bps */
        if (!quot)
                quot = baud_base / 9600;
        info->quot = quot;
        info->timeout = ((info->xmit_fifo_size*HZ*bits*quot) / baud_base);
        info->timeout += HZ/50;         /* Add .02 seconds of slop */
 
        serial_out(info, VAC_UART_INT_MASK, info->IER);
 
        /*
         * Set up parity check flag
         */
#define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
 
        info->read_status_mask = VAC_UART_STATUS_RX_ERR_OVERRUN | \
                VAC_UART_STATUS_TX_EMPTY | VAC_UART_STATUS_RX_READY;
        if (I_INPCK(info->tty))
                info->read_status_mask |= VAC_UART_STATUS_RX_ERR_FRAME | \
                        VAC_UART_STATUS_RX_ERR_PARITY;
        if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
                info->read_status_mask |= VAC_UART_STATUS_RX_BREAK_CHANGE;
 
        /*
         * Characters to ignore
         */
        info->ignore_status_mask = 0;
        if (I_IGNPAR(info->tty))
                info->ignore_status_mask |= VAC_UART_STATUS_RX_ERR_PARITY | \
                        VAC_UART_STATUS_RX_ERR_FRAME;
        if (I_IGNBRK(info->tty)) {
                info->ignore_status_mask |= VAC_UART_STATUS_RX_BREAK_CHANGE;
                /*
                 * If we're ignore parity and break indicators, ignore
                 * overruns too.  (For real raw support).
                 */
                if (I_IGNPAR(info->tty))
                        info->ignore_status_mask |= \
                                VAC_UART_STATUS_RX_ERR_OVERRUN;
        }
        /*
         * !!! ignore all characters if CREAD is not set
         */
        if ((cflag & CREAD) == 0)
                info->ignore_status_mask |= VAC_UART_STATUS_RX_READY;
        save_flags(flags); cli();
 
 
        switch (baud) {
        default:
        case 9600:
                cval |= VAC_UART_MODE_BAUD(7);
                break;
        case 4800:
                cval |= VAC_UART_MODE_BAUD(6);
                break;
        case 2400:
                cval |= VAC_UART_MODE_BAUD(5);
                break;
        case 1200:
                cval |= VAC_UART_MODE_BAUD(4);
                break;
        case 600:
                cval |= VAC_UART_MODE_BAUD(3);
                break;
        case 300:
                cval |= VAC_UART_MODE_BAUD(2);
                break;
#ifndef QUAD_UART_SPEED
        case 150:
#else
        case 38400:
#endif
                cval |= VAC_UART_MODE_BAUD(1);
                break;
#ifndef QUAD_UART_SPEED
        case 75:
#else
        case 19200:
#endif
                cval |= VAC_UART_MODE_BAUD(0);
                break;
        }
 
        /* Baget VAC need some adjustments for computed value */
        cval = vac_uart_mode_fixup(cval);
 
        serial_outp(info, VAC_UART_MODE, cval);
        restore_flags(flags);
}
 
static void rs_put_char(struct tty_struct *tty, unsigned char ch)
{
        struct async_struct *info = (struct async_struct *)tty->driver_data;
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_put_char"))
                return;
 
        if (!tty || !info->xmit_buf)
                return;
 
        save_flags(flags); cli();
        if (info->xmit_cnt >= SERIAL_XMIT_SIZE - 1) {
                restore_flags(flags);
                return;
        }
 
        info->xmit_buf[info->xmit_head++] = ch;
        info->xmit_head &= SERIAL_XMIT_SIZE-1;
        info->xmit_cnt++;
        restore_flags(flags);
}
 
static void rs_flush_chars(struct tty_struct *tty)
{
        struct async_struct *info = (struct async_struct *)tty->driver_data;
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_flush_chars"))
                return;
 
        if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
            !info->xmit_buf)
                return;
 
        save_flags(flags); cli();
        info->IER |= VAC_UART_INT_TX_EMPTY;
        serial_out(info, VAC_UART_INT_MASK, info->IER);
        restore_flags(flags);
}
 
static int rs_write(struct tty_struct * tty, int from_user,
                    const unsigned char *buf, int count)
{
        int     c, ret = 0;
        struct async_struct *info = (struct async_struct *)tty->driver_data;
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_write"))
                return 0;
 
        if (!tty || !info->xmit_buf || !tmp_buf)
                return 0;
 
        save_flags(flags);
        if (from_user) {
                down(&tmp_buf_sem);
                while (1) {
                        c = MIN(count,
                                MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
                                    SERIAL_XMIT_SIZE - info->xmit_head));
                        if (c <= 0)
                                break;
 
                        c -= copy_from_user(tmp_buf, buf, c);
                        if (!c) {
                                if (!ret)
                                        ret = -EFAULT;
                                break;
                        }
                        cli();
                        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);
                        info->xmit_head = ((info->xmit_head + c) &
                                           (SERIAL_XMIT_SIZE-1));
                        info->xmit_cnt += c;
                        restore_flags(flags);
                        buf += c;
                        count -= c;
                        ret += c;
                }
                up(&tmp_buf_sem);
        } else {
                while (1) {
                        cli();
                        c = MIN(count,
                                MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
                                    SERIAL_XMIT_SIZE - info->xmit_head));
                        if (c <= 0) {
                                restore_flags(flags);
                                break;
                        }
                        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);
                        buf += c;
                        count -= c;
                        ret += c;
                }
        }
        if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped &&
            !(info->IER & VAC_UART_INT_TX_EMPTY)) {
                info->IER |= VAC_UART_INT_TX_EMPTY;
                serial_out(info, VAC_UART_INT_MASK, info->IER);
        }
        return ret;
}
 
static int rs_write_room(struct tty_struct *tty)
{
        struct async_struct *info = (struct async_struct *)tty->driver_data;
        int     ret;
 
        if (serial_paranoia_check(info, tty->device, "rs_write_room"))
                return 0;
        ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
        if (ret < 0)
                ret = 0;
        return ret;
}
 
static int rs_chars_in_buffer(struct tty_struct *tty)
{
        struct async_struct *info = (struct async_struct *)tty->driver_data;
 
        if (serial_paranoia_check(info, tty->device, "rs_chars_in_buffer"))
                return 0;
        return info->xmit_cnt;
}
 
static void rs_flush_buffer(struct tty_struct *tty)
{
        struct async_struct *info = (struct async_struct *)tty->driver_data;
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_flush_buffer"))
                return;
 
        save_flags(flags); cli();
        info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
        restore_flags(flags);
 
        wake_up_interruptible(&tty->write_wait);
        if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
            tty->ldisc.write_wakeup)
                (tty->ldisc.write_wakeup)(tty);
}
 
/*
 * This function is used to send a high-priority XON/XOFF character to
 * the device
 */
static void rs_send_xchar(struct tty_struct *tty, char ch)
{
        struct async_struct *info = (struct async_struct *)tty->driver_data;
 
        if (serial_paranoia_check(info, tty->device, "rs_send_char"))
                return;
 
        info->x_char = ch;
        if (ch) {
                /* Make sure transmit interrupts are on */
                info->IER |= VAC_UART_INT_TX_EMPTY;
                serial_out(info, VAC_UART_INT_MASK, info->IER);
        }
}
 
/*
 * ------------------------------------------------------------
 * rs_throttle()
 *
 * This routine is called by the upper-layer tty layer to signal that
 * incoming characters should be throttled.
 * ------------------------------------------------------------
 */
static void rs_throttle(struct tty_struct * tty)
{
        struct async_struct *info = (struct async_struct *)tty->driver_data;
 
#ifdef SERIAL_DEBUG_THROTTLE
        char    buf[64];
 
        baget_printk("throttle %s: %d....\n", tty_name(tty, buf),
               tty->ldisc.chars_in_buffer(tty));
#endif
 
        if (serial_paranoia_check(info, tty->device, "rs_throttle"))
                return;
 
        if (I_IXOFF(tty))
                rs_send_xchar(tty, STOP_CHAR(tty));
}
 
static void rs_unthrottle(struct tty_struct * tty)
{
        struct async_struct *info = (struct async_struct *)tty->driver_data;
#ifdef SERIAL_DEBUG_THROTTLE
        char    buf[64];
 
        baget_printk("unthrottle %s: %d....\n", tty_name(tty, buf),
               tty->ldisc.chars_in_buffer(tty));
#endif
 
        if (serial_paranoia_check(info, tty->device, "rs_unthrottle"))
                return;
 
        if (I_IXOFF(tty)) {
                if (info->x_char)
                        info->x_char = 0;
                else
                        rs_send_xchar(tty, START_CHAR(tty));
        }
}
 
/*
 * ------------------------------------------------------------
 * rs_ioctl() and friends
 * ------------------------------------------------------------
 */
 
static int get_serial_info(struct async_struct * info,
                           struct serial_struct * retinfo)
{
        struct serial_struct tmp;
        struct serial_state *state = info->state;
 
        if (!retinfo)
                return -EFAULT;
        memset(&tmp, 0, sizeof(tmp));
        tmp.type = state->type;
        tmp.line = state->line;
        tmp.port = state->port;
        tmp.irq = state->irq;
        tmp.flags = state->flags;
        tmp.xmit_fifo_size = state->xmit_fifo_size;
        tmp.baud_base = state->baud_base;
        tmp.close_delay = state->close_delay;
        tmp.closing_wait = state->closing_wait;
        tmp.custom_divisor = state->custom_divisor;
        tmp.hub6 = state->hub6;
        if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
                return -EFAULT;
        return 0;
}
 
static int set_serial_info(struct async_struct * info,
                           struct serial_struct * new_info)
{
        struct serial_struct new_serial;
        struct serial_state old_state, *state;
        unsigned int            i,change_irq,change_port;
        int                     retval = 0;
 
        if (copy_from_user(&new_serial,new_info,sizeof(new_serial)))
                return -EFAULT;
        state = info->state;
        old_state = *state;
 
        change_irq = new_serial.irq != state->irq;
        change_port = (new_serial.port != state->port) ||
                (new_serial.hub6 != state->hub6);
 
        if (!capable(CAP_SYS_ADMIN)) {
                if (change_irq || change_port ||
                    (new_serial.baud_base != state->baud_base) ||
                    (new_serial.type != state->type) ||
                    (new_serial.close_delay != state->close_delay) ||
                    (new_serial.xmit_fifo_size != state->xmit_fifo_size) ||
                    ((new_serial.flags & ~ASYNC_USR_MASK) !=
                     (state->flags & ~ASYNC_USR_MASK)))
                        return -EPERM;
                state->flags = ((state->flags & ~ASYNC_USR_MASK) |
                               (new_serial.flags & ASYNC_USR_MASK));
                info->flags = ((state->flags & ~ASYNC_USR_MASK) |
                               (info->flags & ASYNC_USR_MASK));
                state->custom_divisor = new_serial.custom_divisor;
                goto check_and_exit;
        }
 
        new_serial.irq = new_serial.irq;
 
        if ((new_serial.irq >= NR_IRQS) || (new_serial.port > 0xffff) ||
            (new_serial.baud_base == 0) || (new_serial.type < PORT_UNKNOWN) ||
            (new_serial.type > PORT_MAX) || (new_serial.type == PORT_CIRRUS) ||
            (new_serial.type == PORT_STARTECH)) {
                return -EINVAL;
        }
 
        if ((new_serial.type != state->type) ||
            (new_serial.xmit_fifo_size <= 0))
                new_serial.xmit_fifo_size =
                        uart_config[state->type].dfl_xmit_fifo_size;
 
        /* Make sure address is not already in use */
        if (new_serial.type) {
                for (i = 0 ; i < NR_PORTS; i++)
                        if ((state != &rs_table[i]) &&
                            (rs_table[i].port == new_serial.port) &&
                            rs_table[i].type)
                                return -EADDRINUSE;
        }
 
        if ((change_port || change_irq) && (state->count > 1))
                return -EBUSY;
 
        /*
         * OK, past this point, all the error checking has been done.
         * At this point, we start making changes.....
         */
 
        state->baud_base = new_serial.baud_base;
        state->flags = ((state->flags & ~ASYNC_FLAGS) |
                        (new_serial.flags & ASYNC_FLAGS));
        info->flags = ((state->flags & ~ASYNC_INTERNAL_FLAGS) |
                       (info->flags & ASYNC_INTERNAL_FLAGS));
        state->custom_divisor = new_serial.custom_divisor;
        state->type = new_serial.type;
        state->close_delay = new_serial.close_delay * HZ/100;
        state->closing_wait = new_serial.closing_wait * HZ/100;
        info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
        info->xmit_fifo_size = state->xmit_fifo_size =
                new_serial.xmit_fifo_size;
 
        release_region(state->port,8);
        if (change_port || change_irq) {
                /*
                 * We need to shutdown the serial port at the old
                 * port/irq combination.
                 */
                shutdown(info);
                state->irq = new_serial.irq;
                info->port = state->port = new_serial.port;
                info->hub6 = state->hub6 = new_serial.hub6;
        }
        if (state->type != PORT_UNKNOWN)
                request_region(state->port,8,"serial(set)");
 
 
check_and_exit:
        if (!state->port || !state->type)
                return 0;
        if (info->flags & ASYNC_INITIALIZED) {
                if (((old_state.flags & ASYNC_SPD_MASK) !=
                     (state->flags & ASYNC_SPD_MASK)) ||
                    (old_state.custom_divisor != state->custom_divisor)) {
                        if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
                                info->tty->alt_speed = 57600;
                        if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
                                info->tty->alt_speed = 115200;
                        if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
                                info->tty->alt_speed = 230400;
                        if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
                                info->tty->alt_speed = 460800;
                        change_speed(info);
                }
        } else
                retval = startup(info);
        return retval;
}
 
 
/*
 * get_lsr_info - get line status register info
 *
 * Purpose: Let user call ioctl() to get info when the UART physically
 *          is emptied.  On bus types like RS485, the transmitter must
 *          release the bus after transmitting. This must be done when
 *          the transmit shift register is empty, not be done when the
 *          transmit holding register is empty.  This functionality
 *          allows an RS485 driver to be written in user space.
 */
static int get_lsr_info(struct async_struct * info, unsigned int *value)
{
        unsigned short status;
        unsigned int result;
        unsigned long flags;
 
        save_flags(flags); cli();
        status = serial_inw(info, VAC_UART_INT_STATUS);
        restore_flags(flags);
        result = ((status & VAC_UART_STATUS_TX_EMPTY) ? TIOCSER_TEMT : 0);
        return put_user(result,value);
}
 
 
static int get_modem_info(struct async_struct * info, unsigned int *value)
{
        unsigned int result;
 
        result = TIOCM_CAR | TIOCM_DSR;
        return put_user(result,value);
}
 
static int set_modem_info(struct async_struct * info, unsigned int cmd,
                          unsigned int *value)
{
        unsigned int arg;
 
        if (get_user(arg, value))
                return -EFAULT;
        switch (cmd) {
        default:
                return -EINVAL;
        }
        return 0;
}
 
static int do_autoconfig(struct async_struct * info)
{
        int                     retval;
 
        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;
 
        if (info->state->count > 1)
                return -EBUSY;
 
        shutdown(info);
 
        autoconfig(info->state);
 
        retval = startup(info);
        if (retval)
                return retval;
        return 0;
}
 
/*
 * rs_break() --- routine which turns the break handling on or off
 */
static void rs_break(struct tty_struct *tty, int break_state)
{
        struct async_struct * info = (struct async_struct *)tty->driver_data;
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_break"))
                return;
 
        if (!info->port)
                return;
        save_flags(flags); cli();
        if (break_state == -1)
                serial_outp(info, VAC_UART_MODE,
                           serial_inp(info, VAC_UART_MODE) | \
                            VAC_UART_MODE_SEND_BREAK);
        else
                serial_outp(info, VAC_UART_MODE,
                           serial_inp(info, VAC_UART_MODE) & \
                            ~VAC_UART_MODE_SEND_BREAK);
        restore_flags(flags);
}
 
static int rs_ioctl(struct tty_struct *tty, struct file * file,
                    unsigned int cmd, unsigned long arg)
{
        int error;
        struct async_struct * info = (struct async_struct *)tty->driver_data;
        struct async_icount cprev, cnow;        /* kernel counter temps */
        struct serial_icounter_struct *p_cuser; /* user space */
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_ioctl"))
                return -ENODEV;
 
        if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
            (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
            (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
                if (tty->flags & (1 << TTY_IO_ERROR))
                    return -EIO;
        }
 
        switch (cmd) {
                case TIOCMGET:
                        return get_modem_info(info, (unsigned int *) arg);
                case TIOCMBIS:
                case TIOCMBIC:
                case TIOCMSET:
                        return set_modem_info(info, cmd, (unsigned int *) arg);
                case TIOCGSERIAL:
                        return get_serial_info(info,
                                               (struct serial_struct *) arg);
                case TIOCSSERIAL:
                        return set_serial_info(info,
                                               (struct serial_struct *) arg);
                case TIOCSERCONFIG:
                        return do_autoconfig(info);
 
                case TIOCSERGETLSR: /* Get line status register */
                        return get_lsr_info(info, (unsigned int *) arg);
 
                case TIOCSERGSTRUCT:
                        if (copy_to_user((struct async_struct *) arg,
                                         info, sizeof(struct async_struct)))
                                return -EFAULT;
                        return 0;
 
                /*
                 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS)to change
                 * - mask passed in arg for lines of interest
                 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
                 * Caller should use TIOCGICOUNT to see which one it was
                 */
                case TIOCMIWAIT:
                        save_flags(flags); cli();
                        /* note the counters on entry */
                        cprev = info->state->icount;
                        restore_flags(flags);
                        while (1) {
                                interruptible_sleep_on(&info->delta_msr_wait);
                                /* see if a signal did it */
                                if (signal_pending(current))
                                        return -ERESTARTSYS;
                                save_flags(flags); cli();
                                cnow = info->state->icount; /* atomic copy */
                                restore_flags(flags);
                                if (cnow.rng == cprev.rng &&
                                    cnow.dsr == cprev.dsr &&
                                    cnow.dcd == cprev.dcd &&
                                    cnow.cts == cprev.cts)
                                        return -EIO; /* no change => error */
                                if ( ((arg & TIOCM_RNG) &&
                                      (cnow.rng != cprev.rng)) ||
                                     ((arg & TIOCM_DSR) &&
                                      (cnow.dsr != cprev.dsr)) ||
                                     ((arg & TIOCM_CD)  &&
                                      (cnow.dcd != cprev.dcd)) ||
                                     ((arg & TIOCM_CTS) &&
                                      (cnow.cts != cprev.cts)) ) {
                                        return 0;
                                }
                                cprev = cnow;
                        }
                        /* NOTREACHED */
 
                /*
                 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
                 * Return: write counters to the user passed counter struct
                 * NB: both 1->0 and 0->1 transitions are counted except for
                 *     RI where only 0->1 is counted.
                 */
                case TIOCGICOUNT:
                        save_flags(flags); cli();
                        cnow = info->state->icount;
                        restore_flags(flags);
                        p_cuser = (struct serial_icounter_struct *) arg;
                        error = put_user(cnow.cts, &p_cuser->cts);
                        if (error) return error;
                        error = put_user(cnow.dsr, &p_cuser->dsr);
                        if (error) return error;
                        error = put_user(cnow.rng, &p_cuser->rng);
                        if (error) return error;
                        error = put_user(cnow.dcd, &p_cuser->dcd);
                        if (error) return error;
                        error = put_user(cnow.rx, &p_cuser->rx);
                        if (error) return error;
                        error = put_user(cnow.tx, &p_cuser->tx);
                        if (error) return error;
                        error = put_user(cnow.frame, &p_cuser->frame);
                        if (error) return error;
                        error = put_user(cnow.overrun, &p_cuser->overrun);
                        if (error) return error;
                        error = put_user(cnow.parity, &p_cuser->parity);
                        if (error) return error;
                        error = put_user(cnow.brk, &p_cuser->brk);
                        if (error) return error;
                        error = put_user(cnow.buf_overrun, &p_cuser->buf_overrun);
 
                        if (error) return error;
                        return 0;
 
                case TIOCSERGWILD:
                case TIOCSERSWILD:
                       /* "setserial -W" is called in Debian boot */
                        printk ("TIOCSER?WILD ioctl obsolete, ignored.\n");
                        return 0;
 
                default:
                        return -ENOIOCTLCMD;
                }
        return 0;
}
 
static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
{
        struct async_struct *info = (struct async_struct *)tty->driver_data;
        unsigned int cflag = tty->termios->c_cflag;
 
        if (   (cflag == old_termios->c_cflag)
            && (   RELEVANT_IFLAG(tty->termios->c_iflag)
                == RELEVANT_IFLAG(old_termios->c_iflag)))
          return;
 
        change_speed(info);
 
        /* Handle turning off CRTSCTS */
        if ((old_termios->c_cflag & CRTSCTS) &&
            !(cflag & CRTSCTS)) {
                tty->hw_stopped = 0;
                rs_start(tty);
        }
 
}
 
/*
 * ------------------------------------------------------------
 * rs_close()
 *
 * This routine is called when the serial port gets closed.  First, we
 * wait for the last remaining data to be sent.  Then, we unlink its
 * async structure from the interrupt chain if necessary, and we free
 * that IRQ if nothing is left in the chain.
 * ------------------------------------------------------------
 */
static void rs_close(struct tty_struct *tty, struct file * filp)
{
        struct async_struct * info = (struct async_struct *)tty->driver_data;
        struct serial_state *state;
        unsigned long flags;
 
        if (!info || serial_paranoia_check(info, tty->device, "rs_close"))
                return;
 
        state = info->state;
 
        save_flags(flags); cli();
 
        if (tty_hung_up_p(filp)) {
                DBG_CNT("before DEC-hung");
                MOD_DEC_USE_COUNT;
                restore_flags(flags);
                return;
        }
 
#ifdef SERIAL_DEBUG_OPEN
        baget_printk("rs_close ttys%d, count = %d\n",
                     info->line, state->count);
#endif
        if ((tty->count == 1) && (state->count != 1)) {
                /*
                 * Uh, oh.  tty->count is 1, which means that the tty
                 * structure will be freed.  state->count should always
                 * be one in these conditions.  If it's greater than
                 * one, we've got real problems, since it means the
                 * serial port won't be shutdown.
                 */
                baget_printk("rs_close: bad serial port count; "
                             "tty->count is 1, "
                             "state->count is %d\n", state->count);
                state->count = 1;
        }
        if (--state->count < 0) {
                baget_printk("rs_close: bad serial port count for "
                             "ttys%d: %d\n",
                             info->line, state->count);
                state->count = 0;
        }
        if (state->count) {
                DBG_CNT("before DEC-2");
                MOD_DEC_USE_COUNT;
                restore_flags(flags);
                return;
        }
        info->flags |= ASYNC_CLOSING;
        /*
         * Save the termios structure, since this port may have
         * separate termios for callout and dialin.
         */
        if (info->flags & ASYNC_NORMAL_ACTIVE)
                info->state->normal_termios = *tty->termios;
        if (info->flags & ASYNC_CALLOUT_ACTIVE)
                info->state->callout_termios = *tty->termios;
        /*
         * Now we wait for the transmit buffer to clear; and we notify
         * the line discipline to only process XON/XOFF characters.
         */
        tty->closing = 1;
        if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
                tty_wait_until_sent(tty, info->closing_wait);
        /*
         * At this point we stop accepting input.  To do this, we
         * disable the receive line status interrupts, and tell the
         * interrupt driver to stop checking the data ready bit in the
         * line status register.
         */
        info->IER &= ~(VAC_UART_INT_RX_BREAK_CHANGE | VAC_UART_INT_RX_ERRS);
        info->read_status_mask &= ~VAC_UART_STATUS_RX_READY;
        if (info->flags & ASYNC_INITIALIZED) {
                serial_outw(info, VAC_UART_INT_MASK, info->IER);
                /*
                 * Before we drop DTR, make sure the UART transmitter
                 * has completely drained; this is especially
                 * important if there is a transmit FIFO!
                 */
                rs_wait_until_sent(tty, info->timeout);
        }
        shutdown(info);
        if (tty->driver.flush_buffer)
                tty->driver.flush_buffer(tty);
        if (tty->ldisc.flush_buffer)
                tty->ldisc.flush_buffer(tty);
        tty->closing = 0;
        info->event = 0;
        info->tty = 0;
        if (info->blocked_open) {
                if (info->close_delay) {
                        current->state = TASK_INTERRUPTIBLE;
                        schedule_timeout(info->close_delay);
                }
                wake_up_interruptible(&info->open_wait);
        }
        info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE|
                         ASYNC_CLOSING);
        wake_up_interruptible(&info->close_wait);
        MOD_DEC_USE_COUNT;
        restore_flags(flags);
}
 
/*
 * rs_wait_until_sent() --- wait until the transmitter is empty
 */
static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
{
        struct async_struct * info = (struct async_struct *)tty->driver_data;
        unsigned long orig_jiffies, char_time;
        int lsr;
 
        if (serial_paranoia_check(info, tty->device, "rs_wait_until_sent"))
                return;
 
        if (info->state->type == PORT_UNKNOWN)
                return;
 
        if (info->xmit_fifo_size == 0)
                return; /* Just in case.... */
 
        orig_jiffies = jiffies;
        /*
         * Set the check interval to be 1/5 of the estimated time to
         * send a single character, and make it at least 1.  The check
         * interval should also be less than the timeout.
         *
         * Note: we have to use pretty tight timings here to satisfy
         * the NIST-PCTS.
         */
        char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
        char_time = char_time / 5;
        if (char_time == 0)
                char_time = 1;
        if (timeout)
          char_time = MIN(char_time, timeout);
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
        baget_printk("In rs_wait_until_sent(%d) check=%lu...",
                     timeout, char_time);
        baget_printk("jiff=%lu...", jiffies);
#endif
        while (!((lsr = serial_inp(info, VAC_UART_INT_STATUS)) & \
                 VAC_UART_STATUS_TX_EMPTY)) {
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
                baget_printk("lsr = %d (jiff=%lu)...", lsr, jiffies);
#endif
                current->state = TASK_INTERRUPTIBLE;
                schedule_timeout(char_time);
                if (signal_pending(current))
                        break;
                if (timeout && time_after(jiffies, orig_jiffies + timeout))
                        break;
        }
        current->state = TASK_RUNNING;
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
        baget_printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
#endif
}
 
/*
 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
 */
static void rs_hangup(struct tty_struct *tty)
{
        struct async_struct * info = (struct async_struct *)tty->driver_data;
        struct serial_state *state = info->state;
 
        if (serial_paranoia_check(info, tty->device, "rs_hangup"))
                return;
 
        state = info->state;
 
        rs_flush_buffer(tty);
        shutdown(info);
        info->event = 0;
        state->count = 0;
        info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE);
        info->tty = 0;
        wake_up_interruptible(&info->open_wait);
}
 
/*
 * ------------------------------------------------------------
 * rs_open() and friends
 * ------------------------------------------------------------
 */
static int block_til_ready(struct tty_struct *tty, struct file * filp,
                           struct async_struct *info)
{
        DECLARE_WAITQUEUE(wait, current);
        struct serial_state *state = info->state;
        int             retval;
        int             do_clocal = 0,  extra_count = 0;
        unsigned long   flags;
 
        /*
         * If the device is in the middle of being closed, then block
         * until it's done, and then try again.
         */
        if (tty_hung_up_p(filp) ||
            (info->flags & ASYNC_CLOSING)) {
                if (info->flags & ASYNC_CLOSING)
                        interruptible_sleep_on(&info->close_wait);
#ifdef SERIAL_DO_RESTART
                return ((info->flags & ASYNC_HUP_NOTIFY) ?
                        -EAGAIN : -ERESTARTSYS);
#else
                return -EAGAIN;
#endif
        }
 
        /*
         * If this is a callout device, then just make sure the normal
         * device isn't being used.
         */
        if (tty->driver.subtype == SERIAL_TYPE_CALLOUT) {
                if (info->flags & ASYNC_NORMAL_ACTIVE)
                        return -EBUSY;
                if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
                    (info->flags & ASYNC_SESSION_LOCKOUT) &&
                    (info->session != current->session))
                    return -EBUSY;
                if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
                    (info->flags & ASYNC_PGRP_LOCKOUT) &&
                    (info->pgrp != current->pgrp))
                    return -EBUSY;
                info->flags |= ASYNC_CALLOUT_ACTIVE;
                return 0;
        }
 
        /*
         * If non-blocking mode is set, or the port is not enabled,
         * then make the check up front and then exit.
         */
        if ((filp->f_flags & O_NONBLOCK) ||
            (tty->flags & (1 << TTY_IO_ERROR))) {
                if (info->flags & ASYNC_CALLOUT_ACTIVE)
                        return -EBUSY;
                info->flags |= ASYNC_NORMAL_ACTIVE;
                return 0;
        }
 
        if (info->flags & ASYNC_CALLOUT_ACTIVE) {
                if (state->normal_termios.c_cflag & CLOCAL)
                        do_clocal = 1;
        } else {
                if (tty->termios->c_cflag & CLOCAL)
                        do_clocal = 1;
        }
 
        /*
         * Block waiting for the carrier detect and the line to become
         * free (i.e., not in use by the callout).  While we are in
         * this loop, state->count is dropped by one, so that
         * rs_close() knows when to free things.  We restore it upon
         * exit, either normal or abnormal.
         */
        retval = 0;
        add_wait_queue(&info->open_wait, &wait);
#ifdef SERIAL_DEBUG_OPEN
        baget_printk("block_til_ready before block: ttys%d, count = %d\n",
               state->line, state->count);
#endif
        save_flags(flags); cli();
        if (!tty_hung_up_p(filp)) {
                extra_count = 1;
                state->count--;
        }
        restore_flags(flags);
        info->blocked_open++;
        while (1) {
                set_current_state(TASK_INTERRUPTIBLE);
                if (tty_hung_up_p(filp) ||
                    !(info->flags & ASYNC_INITIALIZED)) {
#ifdef SERIAL_DO_RESTART
                        if (info->flags & ASYNC_HUP_NOTIFY)
                                retval = -EAGAIN;
                        else
                                retval = -ERESTARTSYS;
#else
                        retval = -EAGAIN;
#endif
                        break;
                }
                if (!(info->flags & ASYNC_CALLOUT_ACTIVE) &&
                    !(info->flags & ASYNC_CLOSING))
                        break;
                if (signal_pending(current)) {
                        retval = -ERESTARTSYS;
                        break;
                }
#ifdef SERIAL_DEBUG_OPEN
                baget_printk("block_til_ready blocking: ttys%d, count = %d\n",
                       info->line, state->count);
#endif
                schedule();
        }
        current->state = TASK_RUNNING;
        remove_wait_queue(&info->open_wait, &wait);
        if (extra_count)
                state->count++;
        info->blocked_open--;
#ifdef SERIAL_DEBUG_OPEN
        baget_printk("block_til_ready after blocking: ttys%d, count = %d\n",
               info->line, state->count);
#endif
        if (retval)
                return retval;
        info->flags |= ASYNC_NORMAL_ACTIVE;
        return 0;
}
 
static int get_async_struct(int line, struct async_struct **ret_info)
{
        struct async_struct *info;
        struct serial_state *sstate;
 
        sstate = rs_table + line;
        sstate->count++;
        if (sstate->info) {
                *ret_info = sstate->info;
                return 0;
        }
        info = kmalloc(sizeof(struct async_struct), GFP_KERNEL);
        if (!info) {
                sstate->count--;
                return -ENOMEM;
        }
        memset(info, 0, sizeof(struct async_struct));
        init_waitqueue_head(&info->open_wait);
        init_waitqueue_head(&info->close_wait);
        init_waitqueue_head(&info->delta_msr_wait);
        info->magic = SERIAL_MAGIC;
        info->port = sstate->port;
        info->flags = sstate->flags;
        info->xmit_fifo_size = sstate->xmit_fifo_size;
        info->line = line;
        info->tqueue.routine = do_softint;
        info->tqueue.data = info;
        info->state = sstate;
        if (sstate->info) {
                kfree(info);
                *ret_info = sstate->info;
                return 0;
        }
        *ret_info = sstate->info = info;
        return 0;
}
 
/*
 * This routine is called whenever a serial port is opened.  It
 * enables interrupts for a serial port, linking in its async structure into
 * the IRQ chain.   It also performs the serial-specific
 * initialization for the tty structure.
 */
static int rs_open(struct tty_struct *tty, struct file * filp)
{
        struct async_struct     *info;
        int                     retval, line;
        unsigned long           page;
 
        MOD_INC_USE_COUNT;
        line = MINOR(tty->device) - tty->driver.minor_start;
        if ((line < 0) || (line >= NR_PORTS)) {
                MOD_DEC_USE_COUNT;
                return -ENODEV;
        }
        retval = get_async_struct(line, &info);
        if (retval) {
                MOD_DEC_USE_COUNT;
                return retval;
        }
        tty->driver_data = info;
        info->tty = tty;
        if (serial_paranoia_check(info, tty->device, "rs_open")) {
                /* MOD_DEC_USE_COUNT; "info->tty" will cause this */
                return -ENODEV;
        }
 
#ifdef SERIAL_DEBUG_OPEN
        baget_printk("rs_open %s%d, count = %d\n",
                     tty->driver.name, info->line,
                     info->state->count);
#endif
        info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
        if (!tmp_buf) {
                page = get_free_page(GFP_KERNEL);
                if (!page) {
                        /* MOD_DEC_USE_COUNT; "info->tty" will cause this */
                        return -ENOMEM;
                }
                if (tmp_buf)
                        free_page(page);
                else
                        tmp_buf = (unsigned char *) page;
        }
 
        /*
         * If the port is the middle of closing, bail out now
         */
        if (tty_hung_up_p(filp) ||
            (info->flags & ASYNC_CLOSING)) {
                if (info->flags & ASYNC_CLOSING)
                        interruptible_sleep_on(&info->close_wait);
                /* MOD_DEC_USE_COUNT; "info->tty" will cause this */
#ifdef SERIAL_DO_RESTART
                return ((info->flags & ASYNC_HUP_NOTIFY) ?
                        -EAGAIN : -ERESTARTSYS);
#else
                return -EAGAIN;
#endif
        }
 
        /*
         * Start up serial port
         */
        retval = startup(info);
        if (retval) {
                /* MOD_DEC_USE_COUNT; "info->tty" will cause this */
                return retval;
        }
 
        retval = block_til_ready(tty, filp, info);
        if (retval) {
                 /* MOD_DEC_USE_COUNT; "info->tty" will cause this */
#ifdef SERIAL_DEBUG_OPEN
                 baget_printk("rs_open returning after block_til_ready "
                              "with %d\n",
                              retval);
#endif
                 return retval;
        }
 
        if ((info->state->count == 1) &&
            (info->flags & ASYNC_SPLIT_TERMIOS)) {
                if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
                        *tty->termios = info->state->normal_termios;
                else
                        *tty->termios = info->state->callout_termios;
                change_speed(info);
        }
#ifdef CONFIG_SERIAL_CONSOLE
        if (sercons.cflag && sercons.index == line) {
                tty->termios->c_cflag = sercons.cflag;
                sercons.cflag = 0;
                change_speed(info);
        }
#endif
        info->session = current->session;
        info->pgrp = current->pgrp;
 
#ifdef SERIAL_DEBUG_OPEN
        baget_printk("rs_open ttys%d successful...", info->line);
#endif
        return 0;
}
 
/*
 * /proc fs routines....
 */
 
static inline int line_info(char *buf, struct serial_state *state)
{
        struct async_struct *info = state->info, scr_info;
        int     ret;
 
        ret = sprintf(buf, "%d: uart:%s port:%X irq:%d",
                      state->line, uart_config[state->type].name,
                      state->port, state->irq);
 
        if (!state->port || (state->type == PORT_UNKNOWN)) {
                ret += sprintf(buf+ret, "\n");
                return ret;
        }
 
        /*
         * Figure out the current RS-232 lines
         */
        if (!info) {
                info = &scr_info;       /* This is just for serial_{in,out} */
 
                info->magic = SERIAL_MAGIC;
                info->port = state->port;
                info->flags = state->flags;
                info->quot = 0;
                info->tty = 0;
        }
 
        if (info->quot) {
                ret += sprintf(buf+ret, " baud:%d",
                               state->baud_base / info->quot);
        }
 
        ret += sprintf(buf+ret, " tx:%d rx:%d",
                      state->icount.tx, state->icount.rx);
 
        if (state->icount.frame)
                ret += sprintf(buf+ret, " fe:%d", state->icount.frame);
 
        if (state->icount.parity)
                ret += sprintf(buf+ret, " pe:%d", state->icount.parity);
 
        if (state->icount.brk)
                ret += sprintf(buf+ret, " brk:%d", state->icount.brk);
 
        if (state->icount.overrun)
                ret += sprintf(buf+ret, " oe:%d", state->icount.overrun);
 
        return ret;
}
 
int rs_read_proc(char *page, char **start, off_t off, int count,
                 int *eof, void *data)
{
        int i, len = 0, l;
        off_t   begin = 0;
 
        len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version);
        for (i = 0; i < NR_PORTS && len < 4000; i++) {
                l = line_info(page + len, &rs_table[i]);
                len += l;
                if (len+begin > off+count)
                        goto done;
                if (len+begin < off) {
                        begin += len;
                        len = 0;
                }
        }
        *eof = 1;
done:
        if (off >= len+begin)
                return 0;
        *start = page + (off-begin);
        return ((count < begin+len-off) ? count : begin+len-off);
}
 
/*
 * ---------------------------------------------------------------------
 * rs_init() and friends
 *
 * rs_init() is called at boot-time to initialize the serial driver.
 * ---------------------------------------------------------------------
 */
 
/*
 * This routine prints out the appropriate serial driver version
 * number, and identifies which options were configured into this
 * driver.
 */
static _INLINE_ void show_serial_version(void)
{
        printk(KERN_INFO "%s version %s with", serial_name, serial_version);
#ifdef CONFIG_SERIAL_SHARE_IRQ
        printk(" SHARE_IRQ");
#endif
#define SERIAL_OPT
#ifdef CONFIG_SERIAL_DETECT_IRQ
        printk(" DETECT_IRQ");
#endif
#ifdef SERIAL_OPT
        printk(" enabled\n");
#else
        printk(" no serial options enabled\n");
#endif
#undef SERIAL_OPT
}
 
 
/*
 * This routine is called by rs_init() to initialize a specific serial
 * port.  It determines what type of UART chip this serial port is
 * using: 8250, 16450, 16550, 16550A.  The important question is
 * whether or not this UART is a 16550A or not, since this will
 * determine whether or not we can use its FIFO features or not.
 */
 
/*
 *  Functionality of this function is reduced: we already know we have a VAC,
 *  but still need to perform some important actions (see code :-).
 */
static void autoconfig(struct serial_state * state)
{
        struct async_struct *info, scr_info;
        unsigned long flags;
 
        /* Setting up important parameters */
        state->type = VAC_UART_TYPE;
        state->xmit_fifo_size = uart_config[state->type].dfl_xmit_fifo_size;
 
        info = &scr_info;       /* This is just for serial_{in,out} */
 
        info->magic = SERIAL_MAGIC;
        info->port  = state->port;
        info->flags = state->flags;
 
        save_flags(flags); cli();
 
        /* + Flush VAC input fifo */
        (void)serial_in(info, VAC_UART_RX);
        (void)serial_in(info, VAC_UART_RX);
        (void)serial_in(info, VAC_UART_RX);
        (void)serial_in(info, VAC_UART_RX);
 
        /* Disable interrupts */
        serial_outp(info, VAC_UART_INT_MASK, 0);
 
        restore_flags(flags);
}
 
int register_serial(struct serial_struct *req);
void unregister_serial(int line);
 
EXPORT_SYMBOL(register_serial);
EXPORT_SYMBOL(unregister_serial);
 
/*
 *  Important function for VAC UART check and reanimation.
 */
 
static void rs_timer(unsigned long dummy)
{
        static unsigned long last_strobe = 0;
        struct async_struct *info;
        unsigned int    i;
        unsigned long flags;
 
        if ((jiffies - last_strobe) >= RS_STROBE_TIME) {
                for (i=1; i < NR_IRQS; i++) {
                        info = IRQ_ports[i];
                        if (!info)
                                continue;
                        save_flags(flags); cli();
#ifdef CONFIG_SERIAL_SHARE_IRQ
                        if (info->next_port) {
                                do {
                                        serial_out(info, VAC_UART_INT_MASK, 0);
                                        info->IER |= VAC_UART_INT_TX_EMPTY;
                                        serial_out(info, VAC_UART_INT_MASK,
                                                   info->IER);
                                        info = info->next_port;
                                } while (info);
                                rs_interrupt(i, NULL, NULL);
                        } else
#endif /* CONFIG_SERIAL_SHARE_IRQ */
                                rs_interrupt_single(i, NULL, NULL);
                        restore_flags(flags);
                }
        }
        last_strobe = jiffies;
        mod_timer(&vacs_timer, jiffies + RS_STROBE_TIME);
 
        /*
         *  It looks this code for case we share IRQ with console...
         */
 
        if (IRQ_ports[0]) {
                save_flags(flags); cli();
#ifdef CONFIG_SERIAL_SHARE_IRQ
                rs_interrupt(0, NULL, NULL);
#else
                rs_interrupt_single(0, NULL, NULL);
#endif
                restore_flags(flags);
 
                mod_timer(&vacs_timer, jiffies + IRQ_timeout[0] - 2);
        }
}
 
/*
 * The serial driver boot-time initialization code!
 */
int __init rs_init(void)
{
        int i;
        struct serial_state * state;
        extern void atomwide_serial_init (void);
        extern void dualsp_serial_init (void);
 
#ifdef CONFIG_ATOMWIDE_SERIAL
        atomwide_serial_init ();
#endif
#ifdef CONFIG_DUALSP_SERIAL
        dualsp_serial_init ();
#endif
 
        init_bh(SERIAL_BH, do_serial_bh);
        init_timer(&vacs_timer);
        vacs_timer.function = rs_timer;
        vacs_timer.expires = 0;
 
        for (i = 0; i < NR_IRQS; i++) {
                IRQ_ports[i] = 0;
                IRQ_timeout[i] = 0;
        }
 
 
/*
 *  It is not a good idea to share interrupts with console,
 *  but it looks we cannot avoid it.
 */
#if 0
 
#ifdef CONFIG_SERIAL_CONSOLE
        /*
         *      The interrupt of the serial console port
         *      can't be shared.
         */
        if (sercons.flags & CON_CONSDEV) {
                for(i = 0; i < NR_PORTS; i++)
                        if (i != sercons.index &&
                            rs_table[i].irq == rs_table[sercons.index].irq)
                                rs_table[i].irq = 0;
        }
#endif
 
#endif
        show_serial_version();
 
        /* Initialize the tty_driver structure */
 
        memset(&serial_driver, 0, sizeof(struct tty_driver));
        serial_driver.magic = TTY_DRIVER_MAGIC;
        serial_driver.driver_name = "serial";
        serial_driver.name = "ttyS";
        serial_driver.major = TTY_MAJOR;
        serial_driver.minor_start = 64;
        serial_driver.num = NR_PORTS;
        serial_driver.type = TTY_DRIVER_TYPE_SERIAL;
        serial_driver.subtype = SERIAL_TYPE_NORMAL;
        serial_driver.init_termios = tty_std_termios;
        serial_driver.init_termios.c_cflag =
                B9600 | CS8 | CREAD | HUPCL | CLOCAL;
        serial_driver.flags = TTY_DRIVER_REAL_RAW;
        serial_driver.refcount = &serial_refcount;
        serial_driver.table = serial_table;
        serial_driver.termios = serial_termios;
        serial_driver.termios_locked = serial_termios_locked;
 
        serial_driver.open = rs_open;
        serial_driver.close = rs_close;
        serial_driver.write = rs_write;
        serial_driver.put_char = rs_put_char;
        serial_driver.flush_chars = rs_flush_chars;
        serial_driver.write_room = rs_write_room;
        serial_driver.chars_in_buffer = rs_chars_in_buffer;
        serial_driver.flush_buffer = rs_flush_buffer;
        serial_driver.ioctl = rs_ioctl;
        serial_driver.throttle = rs_throttle;
        serial_driver.unthrottle = rs_unthrottle;
        serial_driver.send_xchar = rs_send_xchar;
        serial_driver.set_termios = rs_set_termios;
        serial_driver.stop = rs_stop;
        serial_driver.start = rs_start;
        serial_driver.hangup = rs_hangup;
        serial_driver.break_ctl = rs_break;
        serial_driver.wait_until_sent = rs_wait_until_sent;
        serial_driver.read_proc = rs_read_proc;
 
        /*
         * The callout device is just like normal device except for
         * major number and the subtype code.
         */
        callout_driver = serial_driver;
        callout_driver.name = "cua";
        callout_driver.major = TTYAUX_MAJOR;
        callout_driver.subtype = SERIAL_TYPE_CALLOUT;
        callout_driver.read_proc = 0;
        callout_driver.proc_entry = 0;
 
        if (tty_register_driver(&serial_driver))
                panic("Couldn't register serial driver");
        if (tty_register_driver(&callout_driver))
                panic("Couldn't register callout driver");
 
        for (i = 0, state = rs_table; i < NR_PORTS; i++,state++) {
                state->magic = SSTATE_MAGIC;
                state->line = i;
                state->type = PORT_UNKNOWN;
                state->custom_divisor = 0;
                state->close_delay = 5*HZ/10;
                state->closing_wait = 30*HZ;
                state->callout_termios = callout_driver.init_termios;
                state->normal_termios = serial_driver.init_termios;
                state->icount.cts = state->icount.dsr =
                        state->icount.rng = state->icount.dcd = 0;
                state->icount.rx = state->icount.tx = 0;
                state->icount.frame = state->icount.parity = 0;
                state->icount.overrun = state->icount.brk = 0;
                state->irq = state->irq;
                if (check_region(state->port,8))
                        continue;
                if (state->flags & ASYNC_BOOT_AUTOCONF)
                        autoconfig(state);
        }
 
        /*
         * Detect the IRQ only once every port is initialised,
         * because some 16450 do not reset to 0 the MCR register.
         */
        for (i = 0, state = rs_table; i < NR_PORTS; i++,state++) {
                if (state->type == PORT_UNKNOWN)
                        continue;
                printk(KERN_INFO "ttyS%02d%s at 0x%04x (irq = %d) is a %s\n",
                       state->line,
                       (state->flags & ASYNC_FOURPORT) ? " FourPort" : "",
                       state->port, state->irq,
                       uart_config[state->type].name);
        }
        return 0;
}
 
/*
 * register_serial and unregister_serial allows for serial ports to be
 * configured at run-time, to support PCMCIA modems.
 */
int register_serial(struct serial_struct *req)
{
        int i;
        unsigned long flags;
        struct serial_state *state;
 
        save_flags(flags);
        cli();
        for (i = 0; i < NR_PORTS; i++) {
                if (rs_table[i].port == req->port)
                        break;
        }
        if (i == NR_PORTS) {
                for (i = 0; i < NR_PORTS; i++)
                        if ((rs_table[i].type == PORT_UNKNOWN) &&
                            (rs_table[i].count == 0))
                                break;
        }
        if (i == NR_PORTS) {
                restore_flags(flags);
                return -1;
        }
        state = &rs_table[i];
        if (rs_table[i].count) {
                restore_flags(flags);
                printk("Couldn't configure serial #%d (port=%d,irq=%d): "
                       "device already open\n", i, req->port, req->irq);
                return -1;
        }
        state->irq = req->irq;
        state->port = req->port;
        state->flags = req->flags;
 
        autoconfig(state);
        if (state->type == PORT_UNKNOWN) {
                restore_flags(flags);
                printk("register_serial(): autoconfig failed\n");
                return -1;
        }
        restore_flags(flags);
 
        printk(KERN_INFO "tty%02d at 0x%04x (irq = %d) is a %s\n",
               state->line, state->port, state->irq,
               uart_config[state->type].name);
        return state->line;
}
 
void unregister_serial(int line)
{
        unsigned long flags;
        struct serial_state *state = &rs_table[line];
 
        save_flags(flags);
        cli();
        if (state->info && state->info->tty)
                tty_hangup(state->info->tty);
        state->type = PORT_UNKNOWN;
        printk(KERN_INFO "tty%02d unloaded\n", state->line);
        restore_flags(flags);
}
 
#ifdef MODULE
int init_module(void)
{
        return rs_init();
}
 
void cleanup_module(void)
{
        unsigned long flags;
        int e1, e2;
        int i;
 
        printk("Unloading %s: version %s\n", serial_name, serial_version);
        save_flags(flags);
        cli();
 
        del_timer_sync(&vacs_timer);
        remove_bh(SERIAL_BH);
 
        if ((e1 = tty_unregister_driver(&serial_driver)))
                printk("SERIAL: failed to unregister serial driver (%d)\n",
                       e1);
        if ((e2 = tty_unregister_driver(&callout_driver)))
                printk("SERIAL: failed to unregister callout driver (%d)\n",
                       e2);
        restore_flags(flags);
 
        for (i = 0; i < NR_PORTS; i++) {
                if (rs_table[i].type != PORT_UNKNOWN)
                        release_region(rs_table[i].port, 8);
        }
        if (tmp_buf) {
                free_page((unsigned long) tmp_buf);
                tmp_buf = NULL;
        }
}
#endif /* MODULE */
 
 
/*
 * ------------------------------------------------------------
 * Serial console driver
 * ------------------------------------------------------------
 */
#ifdef CONFIG_SERIAL_CONSOLE
 
#define BOTH_EMPTY (VAC_UART_STATUS_TX_EMPTY | VAC_UART_STATUS_TX_EMPTY)
 
/*
 *      Wait for transmitter & holding register to empty
 */
static inline void wait_for_xmitr(struct async_struct *info)
{
        int lsr;
        unsigned int tmout = 1000000;
 
        do {
                lsr = serial_inp(info, VAC_UART_INT_STATUS);
                if (--tmout == 0) break;
        } while ((lsr & BOTH_EMPTY) != BOTH_EMPTY);
}
 
/*
 *      Print a string to the serial port trying not to disturb
 *      any possible real use of the port...
 */
static void serial_console_write(struct console *co, const char *s,
                                unsigned count)
{
        struct serial_state *ser;
        int ier;
        unsigned i;
        struct async_struct scr_info; /* serial_{in,out} because HUB6 */
 
        ser = rs_table + co->index;
        scr_info.magic = SERIAL_MAGIC;
        scr_info.port = ser->port;
        scr_info.flags = ser->flags;
 
        /*
         *      First save the IER then disable the interrupts
         */
        ier = serial_inp(&scr_info, VAC_UART_INT_MASK);
        serial_outw(&scr_info, VAC_UART_INT_MASK, 0x00);
 
        /*
         *      Now, do each character
         */
        for (i = 0; i < count; i++, s++) {
                wait_for_xmitr(&scr_info);
 
                /*
                 *      Send the character out.
                 *      If a LF, also do CR...
                 */
                serial_outp(&scr_info, VAC_UART_TX, (unsigned short)*s << 8);
                if (*s == 10) {
                        wait_for_xmitr(&scr_info);
                        serial_outp(&scr_info, VAC_UART_TX, 13 << 8);
                }
        }
 
        /*
         *      Finally, Wait for transmitter & holding register to empty
         *      and restore the IER
         */
        wait_for_xmitr(&scr_info);
        serial_outp(&scr_info, VAC_UART_INT_MASK, ier);
}
 
static kdev_t serial_console_device(struct console *c)
{
        return MKDEV(TTY_MAJOR, 64 + c->index);
}
 
/*
 *      Setup initial baud/bits/parity. We do two things here:
 *      - construct a cflag setting for the first rs_open()
 *      - initialize the serial port
 *      Return non-zero if we didn't find a serial port.
 */
static int __init serial_console_setup(struct console *co, char *options)
{
        struct serial_state *ser;
        unsigned cval;
        int     baud = 9600;
        int     bits = 8;
        int     parity = 'n';
        int     cflag = CREAD | HUPCL | CLOCAL;
        int     quot = 0;
        char    *s;
        struct async_struct scr_info; /* serial_{in,out} because HUB6 */
 
        if (options) {
                baud = simple_strtoul(options, NULL, 10);
                s = options;
                while(*s >= '0' && *s <= '9')
                        s++;
                if (*s) parity = *s++;
                if (*s) bits   = *s - '0';
        }
 
        /*
         *      Now construct a cflag setting.
         */
        switch(baud) {
                case 1200:
                        cflag |= B1200;
                        break;
                case 2400:
                        cflag |= B2400;
                        break;
                case 4800:
                        cflag |= B4800;
                        break;
                case 19200:
                        cflag |= B19200;
                        break;
                case 38400:
                        cflag |= B38400;
                        break;
                case 57600:
                        cflag |= B57600;
                        break;
                case 115200:
                        cflag |= B115200;
                        break;
                case 9600:
                default:
                        cflag |= B9600;
                        break;
        }
        switch(bits) {
                case 7:
                        cflag |= CS7;
                        break;
                default:
                case 8:
                        cflag |= CS8;
                        break;
        }
        switch(parity) {
                case 'o': case 'O':
                        cflag |= PARODD;
                        break;
                case 'e': case 'E':
                        cflag |= PARENB;
                        break;
        }
        co->cflag = cflag;
 
        /*
         *      Divisor, bytesize and parity
         */
        ser = rs_table + co->index;
        scr_info.magic = SERIAL_MAGIC;
        scr_info.port = ser->port;
        scr_info.flags = ser->flags;
 
        quot = ser->baud_base / baud;
        cval = cflag & (CSIZE | CSTOPB);
 
        cval >>= 4;
 
        cval &= ~VAC_UART_MODE_PARITY_ENABLE;
        if (cflag & PARENB)
                cval |= VAC_UART_MODE_PARITY_ENABLE;
        if (cflag & PARODD)
                cval |= VAC_UART_MODE_PARITY_ODD;
 
        /*
         *      Disable UART interrupts, set DTR and RTS high
         *      and set speed.
         */
        switch (baud) {
        default:
        case 9600:
                cval |= VAC_UART_MODE_BAUD(7);
                break;
        case 4800:
                cval |= VAC_UART_MODE_BAUD(6);
                break;
        case 2400:
                cval |= VAC_UART_MODE_BAUD(5);
                break;
        case 1200:
                cval |= VAC_UART_MODE_BAUD(4);
                break;
        case 600:
                cval |= VAC_UART_MODE_BAUD(3);
                break;
        case 300:
                cval |= VAC_UART_MODE_BAUD(2);
                break;
#ifndef QUAD_UART_SPEED
        case 150:
#else
        case 38400:
#endif
                cval |= VAC_UART_MODE_BAUD(1);
                break;
#ifndef QUAD_UART_SPEED
        case 75:
#else
        case 19200:
#endif
                cval |= VAC_UART_MODE_BAUD(0);
                break;
        }
 
        /* Baget VAC need some adjustments for computed value */
        cval = vac_uart_mode_fixup(cval);
 
        serial_outp(&scr_info, VAC_UART_MODE, cval);
        serial_outp(&scr_info, VAC_UART_INT_MASK, 0);
 
        return 0;
}
 
static struct console sercons = {
        .name           = "ttyS",
        .write          = serial_console_write,
        .device         = serial_console_device,
        .setup          = serial_console_setup,
        .flags          = CON_PRINTBUFFER,
        .index          = -1,
};
 
/*
 *      Register console.
 */
long __init serial_console_init(long kmem_start, long kmem_end)
{
        register_console(&sercons);
        return kmem_start;
}
#endif
 
#ifdef CONFIG_KGDB
#undef PRINT_DEBUG_PORT_INFO
 
/*
 * This is the interface to the remote debugger stub.
 * I've put that here to be able to control the serial
 * device more directly.
 */
 
static int initialized;
 
static int rs_debug_init(struct async_struct *info)
{
        int quot;
 
        autoconfig(info);       /* autoconfigure ttyS0, whatever that is */
 
#ifdef PRINT_DEBUG_PORT_INFO
        baget_printk("kgdb debug interface:: tty%02d at 0x%04x",
                     info->line, info->port);
        switch (info->type) {
                case PORT_8250:
                        baget_printk(" is a 8250\n");
                        break;
                case PORT_16450:
                        baget_printk(" is a 16450\n");
                        break;
                case PORT_16550:
                        baget_printk(" is a 16550\n");
                        break;
                case PORT_16550A:
                        baget_printk(" is a 16550A\n");
                        break;
                case PORT_16650:
                        baget_printk(" is a 16650\n");
                        break;
                default:
                        baget_printk(" is of unknown type -- unusable\n");
                        break;
        }
#endif
 
        if (info->port == PORT_UNKNOWN)
                return -1;
 
        /*
         * Clear all interrupts
         */
 
        (void)serial_inp(info, VAC_UART_INT_STATUS);
        (void)serial_inp(info, VAC_UART_RX);
 
        /*
         * Now, initialize the UART
         */
        serial_outp(info,VAC_UART_MODE,VAC_UART_MODE_INITIAL); /* reset DLAB */
        if (info->flags & ASYNC_FOURPORT) {
                info->MCR = UART_MCR_DTR | UART_MCR_RTS;
                info->MCR_noint = UART_MCR_DTR | UART_MCR_OUT1;
        } else {
                info->MCR = UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2;
                info->MCR_noint = UART_MCR_DTR | UART_MCR_RTS;
        }
 
        info->MCR = info->MCR_noint;         /* no interrupts, please */
        /*
         * and set the speed of the serial port
         * (currently hardwired to 9600 8N1
         */
 
        quot = info->baud_base / 9600;       /* baud rate is fixed to 9600 */
        /* FIXME: if rs_debug interface is needed, we need to set speed here */
 
        return 0;
}
 
int putDebugChar(char c)
{
        struct async_struct *info = rs_table;
 
        if (!initialized) {             /* need to init device first */
                if (rs_debug_init(info) == 0)
                        initialized = 1;
                else
                        return 0;
        }
 
        while ((serial_inw(info, VAC_UART_INT_STATUS) & \
                VAC_UART_STATUS_TX_EMPTY) == 0)
                ;
        serial_out(info, VAC_UART_TX, (unsigned short)c << 8);
 
        return 1;
}
 
char getDebugChar(void)
{
        struct async_struct *info = rs_table;
 
        if (!initialized) {             /* need to init device first */
                if (rs_debug_init(info) == 0)
                        initialized = 1;
                else
                        return 0;
        }
        while (!(serial_inw(info, VAC_UART_INT_STATUS) & \
                 VAC_UART_STATUS_RX_READY))
                ;
 
        return(serial_inp(info, VAC_UART_RX));
}
 
#endif /* CONFIG_KGDB */
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[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [drivers/] [char/] [vac-serial.c] - Blame information for rev 1765

Line No.	Rev	Author	Line
1	1275	phoenix	`/*`
2			`* vacserial.c: VAC UART serial driver`
3			`* This code stealed and adopted from linux/drivers/char/serial.c`
4			`* See that for author info`
5			`*`
6			`* Copyright (C) 1998 Gleb Raiko & Vladimir Roganov`
7			`*/`
8
9			`#undef SERIAL_PARANOIA_CHECK`
10			`#define CONFIG_SERIAL_NOPAUSE_IO`
11			`#define SERIAL_DO_RESTART`
12
13			`#ifndef CONFIG_SERIAL_SHARE_IRQ`
14			`#define CONFIG_SERIAL_SHARE_IRQ`
15			`#endif`
16
17			`/* Set of debugging defines */`
18
19			`#undef SERIAL_DEBUG_INTR`
20			`#undef SERIAL_DEBUG_OPEN`
21			`#undef SERIAL_DEBUG_FLOW`
22			`#undef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT`
23
24			`#define RS_STROBE_TIME (10*HZ)`
25			`#define RS_ISR_PASS_LIMIT 2 /* Beget is not a super-computer (old=256) */`
26
27			`#define IRQ_T(state) \`
28			`((state->flags & ASYNC_SHARE_IRQ) ? SA_SHIRQ : SA_INTERRUPT)`
29
30			`#define SERIAL_INLINE`
31
32			`#if defined(MODULE) && defined(SERIAL_DEBUG_MCOUNT)`
33			`#define DBG_CNT(s) baget_printk("(%s):[%x] refc=%d, serc=%d, ttyc=%d-> %s\n", \`
34			`kdevname(tty->device),(info->flags),serial_refcount,info->count,tty->count,s)`
35			`#else`
36			`#define DBG_CNT(s)`
37			`#endif`
38
39			`#define QUAD_UART_SPEED /* Useful for Baget */`
40