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[/] [or1k/] [trunk/] [rc203soc/] [sw/] [uClinux/] [drivers/] [char/] [68302serial.c] - Blame information for rev 1765

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/* 68302serial.c: Serial port driver for 68302 microcontroller
 *
 * Based on:
 *
 * drivers/char/68328serial.c
 */
 
#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/config.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/kernel.h>
 
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/system.h>
#include <asm/segment.h>
#include <asm/bitops.h>
#include <asm/delay.h>
#if 0
#include <asm/kdebug.h>
#endif
 
#include "68302serial.h"
 
#define USE_INTS        1
//#undef USE_INTS
#undef USE_ONLY_RX_INTS
 
static int m68k_use_ints=0;
#define SET_INTS_MODE(x)        m68k_use_ints=x
 
static struct m68k_serial m68k_soft;
 
struct tty_struct m68k_ttys;
/** struct tty_struct *m68k_constty; **/
 
/* Console hooks... */
/*static int m68k_cons_chanout = 0;
static int m68k_cons_chanin = 0;*/
 
struct m68k_serial *m68k_consinfo = 0;
 
#if 0
static unsigned char kgdb_regs[16] = {
        0, 0, 0,                     /* write 0, 1, 2 */
        (Rx8 | RxENABLE),            /* write 3 */
        (X16CLK | SB1 | PAR_EVEN),   /* write 4 */
        (Tx8 | TxENAB),              /* write 5 */
        0, 0, 0,                     /* write 6, 7, 8 */
        (NV),                        /* write 9 */
        (NRZ),                       /* write 10 */
        (TCBR | RCBR),               /* write 11 */
        0, 0,                        /* BRG time constant, write 12 + 13 */
        (BRSRC | BRENABL),           /* write 14 */
        (DCDIE)                      /* write 15 */
};
#endif
 
extern u_long clock_frequency;
#define M68K_CLOCK clock_frequency
#if 0
#ifdef CONFIG_CLOCK_20MHz
#define M68K_CLOCK (20000000) /* FIXME: 16MHz is likely wrong */
#else
#define M68K_CLOCK (25000000) /* FIXME: 16MHz is likely wrong */
#endif
#endif
 
DECLARE_TASK_QUEUE(tq_serial);
 
struct tq_struct serialpoll;
 
struct tty_driver serial_driver, callout_driver;
static int serial_refcount;
 
/* serial subtype definitions */
#define SERIAL_TYPE_NORMAL      1
#define SERIAL_TYPE_CALLOUT     2
 
/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS 256
 
/* Debugging... DEBUG_INTR is bad to use when one of the zs
 * lines is your console ;(
 */
#undef SERIAL_DEBUG_INTR
#undef SERIAL_DEBUG_OPEN
#undef SERIAL_DEBUG_FLOW
 
#define RS_ISR_PASS_LIMIT 256
 
#define _INLINE_
 
static void serpoll(void *data);
 
static void change_speed(struct m68k_serial *info);
 
static struct tty_struct *serial_table[2];
static struct termios *serial_termios[2];
static struct termios *serial_termios_locked[2];
 
#ifndef MIN
#define MIN(a,b)        ((a) < (b) ? (a) : (b))
#endif
 
#define CONSOLE_SC
 
static char prompt0,prompt1,prompt2;
static char     rx_buffer[128];         // a little buffer for console SCC
static void scc0_xmit_char(char ch);
static void scc0_xmit_string(char *p, int len);
static void scc0_start_rx(char bd, char *p_start, ushort size, char last);
static void scc_wait_EOT(ushort scc, ushort bd);
static void scc68302_init(void);
static void scc68302_speed(unsigned baud, unsigned cflag);
static int      scc_cmd(ushort scc, ushort opcode);
 
#define SCC_EOT(X,Y)    (ushort)(!(SCC_TXBD_1W(X,Y) & 0x8000))
 
static ushort sccmask[]={IxR_SCC1, IxR_SCC2, IxR_SCC3};
 
#define scc_irq_enable(X)       IMR |= sccmask[X];
#define scc_irq_disable(X)      IMR     &= ~sccmask[X];
#define scc_clear_ev(X,Y)       SCCE(X) |= Y;
#define scc_clear_isr(X)        ISR |= sccmask[X];
 
#define scc_mask(X)             SCCM(X)=0
// unmask CTS, TX, RX
#define scc_unmask(X)   SCCM(X)=0x83    
 
void tx_enable(ushort scc);
void rx_enable(ushort scc);
void tx_disable(ushort scc);
void rx_disable(ushort scc);
void tx_stop(ushort scc);
void tx_start(ushort scc);
void rx_stop(ushort scc);
void rx_start(ushort scc);
 
 
void _INLINE_ tx_enable(ushort scc){
        SCM(scc) |= SCCM_ENT;
        if(m68k_use_ints)
                SCCM(scc) |= SCCE_TX;
}
void _INLINE_ rx_enable(ushort scc){
        SCM(scc) |= SCCM_ENR;
        if(m68k_use_ints)
                SCCM(scc) |= SCCE_RX;
}
void _INLINE_ tx_disable(ushort scc){
        SCM(scc) &= ~SCCM_ENT;
        SCCM(scc) &= ~SCCE_TX;
}
void _INLINE_ rx_disable(ushort scc){
        SCM(scc) &= ~SCCM_ENR;
        SCCM(scc) &= ~SCCE_RX;
}
 
void _INLINE_ tx_stop(ushort scc){
        scc_cmd(scc, CR_OP_STOP_TX);
        tx_disable(scc);
}
void _INLINE_ tx_start(ushort scc){
        scc_cmd(scc, CR_OP_REST_TX);
        tx_enable(scc);
}
void _INLINE_ rx_stop(ushort scc){
        rx_disable(scc);
}
void _INLINE_ rx_start(ushort scc){
        scc_cmd(scc, CR_OP_HUNT_MODE);
        rx_enable(scc);
}
 
 
/*
 * tmp_buf is used as a temporary buffer by serial_write.  We need to
 * lock it in case the memcpy_fromfs blocks while swapping in a page,
 * and some other program tries to do a serial write at the same time.
 * Since the lock will only come under contention when the system is
 * swapping and available memory is low, it makes sense to share one
 * buffer across all the serial ports, since it significantly saves
 * memory if large numbers of serial ports are open.
 */
static unsigned char tmp_buf[4096]; /* This is cheating */
static struct semaphore tmp_buf_sem = MUTEX;
 
static inline int serial_paranoia_check(struct m68k_serial *info,
                                        dev_t device, const char *routine)
{
#ifdef SERIAL_PARANOIA_CHECK
        static const char *badmagic =
                "Warning: bad magic number for serial struct (%d, %d) in %s\n";
        static const char *badinfo =
                "Warning: null m68k_serial for (%d, %d) in %s\n";
 
        if (!info) {
                printk(badinfo, MAJOR(device), MINOR(device), routine);
                return 1;
        }
        if (info->magic != SERIAL_MAGIC) {
                printk(badmagic, MAJOR(device), MINOR(device), routine);
                return 1;
        }
#endif
        return 0;
}
 
/* Sets or clears DTR/RTS on the requested line */
static inline void m68k_rtsdtr(struct m68k_serial *ss, int set)
{
        if(set) {
                /* set the RTS/CTS line */
        } else {
                /* clear it */
        }
        return;
}
 
static inline void kgdb_chaninit(struct m68k_serial *ss, int intson, int bps)
{
#if 0
        int brg;
 
        if(intson) {
                kgdb_regs[R1] = INT_ALL_Rx;
                kgdb_regs[R9] |= MIE;
        } else {
                kgdb_regs[R1] = 0;
                kgdb_regs[R9] &= ~MIE;
        }
        brg = BPS_TO_BRG(bps, ZS_CLOCK/16);
        kgdb_regs[R12] = (brg & 255);
        kgdb_regs[R13] = ((brg >> 8) & 255);
        load_zsregs(ss->m68k_channel, kgdb_regs);
#endif
}
 
 
/*
 * ------------------------------------------------------------
 * 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 m68k_serial *info = (struct m68k_serial *)tty->driver_data;
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_stop"))
                return;
 
        save_flags(flags); cli();
        tx_stop(0);
        rx_stop(0);
        restore_flags(flags);
}
 
static void rs_put_char(char ch)
{
        int flags, loops = 0;
 
        save_flags(flags); cli();
                scc_wait_EOT(0,0);
                scc0_xmit_char(ch);
                scc_wait_EOT(0,0);
        restore_flags(flags);
}
 
 
static void rs_start(struct tty_struct *tty)
{
        struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_start"))
                return;
 
        save_flags(flags); cli();
        tx_start(0);
        scc0_start_rx(0,rx_buffer, 3,1);
        rx_start(0);
        restore_flags(flags);
}
 
/* Drop into either the boot monitor or kadb upon receiving a break
 * from keyboard/console input.
 */
static void batten_down_hatches(void)
{
        /* If we are doing kadb, we call the debugger
         * else we just drop into the boot monitor.
         * Note that we must flush the user windows
         * first before giving up control.
         */
#if 0
        if((((unsigned long)linux_dbvec)>=DEBUG_FIRSTVADDR) &&
           (((unsigned long)linux_dbvec)<=DEBUG_LASTVADDR))
                sp_enter_debugger();
        else
                panic("m68k_serial: batten_down_hatches");
        return;
#endif
}
 
/*
 * ----------------------------------------------------------------------
 *
 * 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 m68k_serial *info,
                                    int event)
{
        info->event |= 1 << event;
        queue_task_irq_off(&info->tqueue, &tq_serial);
        mark_bh(SERIAL_BH);
}
 
extern void breakpoint(void);  /* For the KGDB frame character */
 
static _INLINE_ void receive_chars(struct m68k_serial *info, struct pt_regs *regs, unsigned short status)
{
        unsigned char ch;
        int count,stat;
#if 1
        // hack to receive chars by polling from anywhere
        struct m68k_serial * info1 = &m68k_soft;
        struct tty_struct *tty = info1->tty;
        if (!(info->flags & S_INITIALIZED))
                return;
#else
        struct tty_struct *tty = info->tty;
#endif  
        count = SCC_RXBD_2W(0,0);
        stat = SCC_RXBD_1W(0,0);
        // hack to receive chars by polling only BD fields
        if (stat & 0x8000 || !count){
                return;
        }
        ch = rx_buffer[0];
        if(info->is_cons) {
                if(status & SCCE_BRK) { /* whee, break received */
                        batten_down_hatches();
                        /*rs_recv_clear(info->m68k_channel);*/
                        return;
                } else if (ch == 0x10) { /* ^P */
                        show_state();
                        show_free_areas();
                        show_buffers();
                        show_net_buffers();
                        return;
                } else if (ch == 0x12) { /* ^R */
                        hard_reset_now();
                        return;
                }
                /* It is a 'keyboard interrupt' ;-) */
                wake_up(&keypress_wait);
        }
        /* Look for kgdb 'stop' character, consult the gdb documentation
         * for remote target debugging and arch/sparc/kernel/sparc-stub.c
         * to see how all this works.
         */
        /*if((info->kgdb_channel) && (ch =='\003')) {
                breakpoint();
                goto clear_and_exit;
        }*/
 
        if(!tty)
                goto clear_and_exit;
 
        if (tty->flip.count >= TTY_FLIPBUF_SIZE)
                queue_task_irq_off(&tty->flip.tqueue, &tq_timer);
        tty->flip.count++;
        if(stat & RX_BD_PR)
                *tty->flip.flag_buf_ptr++ = TTY_PARITY;
        else if(stat & RX_BD_OV)
                *tty->flip.flag_buf_ptr++ = TTY_OVERRUN;
        else if(stat & RX_BD_FR)
                *tty->flip.flag_buf_ptr++ = TTY_FRAME;
        else
                *tty->flip.flag_buf_ptr++ = 0; /* XXX */
        *tty->flip.char_buf_ptr++ = ch;
 
        queue_task_irq_off(&tty->flip.tqueue, &tq_timer);
 
clear_and_exit:
        scc0_start_rx(0,rx_buffer,1,1);
        return;
}
 
static _INLINE_ void transmit_chars(struct m68k_serial *info)
{
        if (info->x_char) {
                /* Send next char */
                scc0_xmit_char(info->x_char);
                info->x_char = 0;
                goto clear_and_return;
        }
 
        if((info->xmit_cnt <= 0) || info->tty->stopped) {
                /* That's peculiar... */
//              tx_stop(0);
                goto clear_and_return;
        }
 
        /* Send char */
        scc0_xmit_char(info->xmit_buf[info->xmit_tail++]);
        info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
        info->xmit_cnt--;
 
        if (info->xmit_cnt < WAKEUP_CHARS)
                rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
 
        if(info->xmit_cnt <= 0) {
//              tx_stop(0);
                goto clear_and_return;
        }
 
clear_and_return:
        /* Clear interrupt (should be auto)*/
        return;
}
 
static _INLINE_ void status_handle(struct m68k_serial *info, unsigned short status)
{
#if 0
        if(status & DCD) {
                if((info->tty->termios->c_cflag & CRTSCTS) &&
                   ((info->curregs[3] & AUTO_ENAB)==0)) {
                        info->curregs[3] |= AUTO_ENAB;
                        info->pendregs[3] |= AUTO_ENAB;
                        write_zsreg(info->m68k_channel, 3, info->curregs[3]);
                }
        } else {
                if((info->curregs[3] & AUTO_ENAB)) {
                        info->curregs[3] &= ~AUTO_ENAB;
                        info->pendregs[3] &= ~AUTO_ENAB;
                        write_zsreg(info->m68k_channel, 3, info->curregs[3]);
                }
        }
#endif
        /* Whee, if this is console input and this is a
         * 'break asserted' status change interrupt, call
         * the boot prom.
         */
        if((status & SCCE_BRK) && info->break_abort)
                batten_down_hatches();
 
        /* XXX Whee, put in a buffer somewhere, the status information
         * XXX whee whee whee... Where does the information go...
         */
        return;
}
 
/*
 * This is the serial driver's generic interrupt routine
 */
void rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
{
        struct m68k_serial * info = &m68k_soft;
        ushort status;
        status = SCCE(0);
 
        if(m68k_use_ints){
                if (status & SCCE_TX) {
                        scc_clear_ev(0,SCCE_TX);
                        transmit_chars(info);
                }
                if (status & SCCE_RX){
                        scc_clear_ev(0,SCCE_RX);
                        receive_chars(info, regs, status);
                }
        }else{
                receive_chars(info, regs, status);
        }
        if (status & (SCCE_IDLE | SCCE_BRK | SCCE_CTS | SCCE_CD | SCCE_CCR | SCCE_BSY)) status_handle(info, status);
        scc_clear_isr(0);
 
        if(!m68k_use_ints)
                queue_task_irq_off(&serialpoll, &tq_timer);
        return;
}
static void serpoll(void *data){
        rs_interrupt(0, NULL, NULL);
}
 
/*
 * -------------------------------------------------------------------
 * 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 m68k_serial      *info = (struct m68k_serial *) private_;
        struct tty_struct       *tty;
 
        tty = info->tty;
        if (!tty)
                return;
 
        if (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);
        }
}
 
/*
 * This routine is called from the scheduler tqueue when the interrupt
 * routine has signalled that a hangup has occurred.  The path of
 * hangup processing is:
 *
 *      serial interrupt routine -> (scheduler tqueue) ->
 *      do_serial_hangup() -> tty->hangup() -> rs_hangup()
 *
 */
static void do_serial_hangup(void *private_)
{
        struct m68k_serial      *info = (struct m68k_serial *) private_;
        struct tty_struct       *tty;
 
        tty = info->tty;
        if (!tty)
                return;
 
        tty_hangup(tty);
}
 
 
/*
 * This subroutine is called when the RS_TIMER goes off.  It is used
 * by the serial driver to handle ports that do not have an interrupt
 * (irq=0).  This doesn't work at all for 16450's, as a sun has a Z8530.
 */
 
static void rs_timer(void)
{
        panic("rs_timer called\n");
        return;
}
static void scc68302_init(void){
        SIMODE = 0;
        SCC_MRBLR(0) = 3;
        SCC_MAX_IDL(0)=0xF;
        SCC_RFCR(0)= 0;
        SCC_BRKCR(0)= 1;
        SCC_PAREC(0)=0;
        SCC_FRMEC(0)=0;
        SCC_NOSEC(0)=0;
        SCC_BRKEC(0)=0;
        SCC_UADDR1(0)=0;
        SCC_UADDR2(0)=0;
        SCC_CARACT(0)=0x8000;
        SCCE(0)=0xFF;
        SCCM(0)=0;                                /* all it disabled */
        SCC_TXBD_1W(0,0) = 0x2000;                /* block emission */
}
 
static void scc68302_speed(unsigned baud, unsigned cflag){
        unsigned format;
 
        if ((20000000 == M68K_CLOCK))
        {
                SCON(0) = 2*(ushort)((M68K_CLOCK/16)/baud-1);
        }
        else if ((25000000 == M68K_CLOCK))
        {
        if (baud > 115200)
                baud = 115200;
        if (baud != 115200 && baud != 9600)
                baud = 57600;
        switch(baud){
                case 115200:
                        SCON(0)=0x1A;    /* 115200 */
                        break;
                case 57600:
                        SCON(0)=0x34;    /* 57600 */
                        break;
                case 9600:
                        SCON(0)=0x144; /* 9600 */
                        break;
                default:
                        SCON(0)=0x142;
                        break;
        }
        }
 
        /* set parity */
        SCM(0)=0x171;                    /* no parity normal uart 8 bits 1 stop bit */
 
        if (cflag != 0xffff){
                format = SCM(0)& 0x3F;   /* dont change the common settings */
                if ((cflag & CSIZE) == CS8)
                        format |= SCM_CL;
 
                if (cflag & CSTOPB)
                        format |= SCM_SL;
 
                if (cflag & PARENB)
                        format |= SCM_PEN;
 
                if (cflag & PARODD)
                        format |= SCM_ODD;
 
                SCM(0) = format;
        }
        tx_start(0);
        scc0_start_rx(0,rx_buffer, 3,1);
        rx_start(0);
}
static int      scc_cmd(ushort scc, ushort opcode){
        SCR = scc<<1 | opcode | CR_FLG;
        while(SCR & CR_FLG){;}
}
static void scc_wait_EOT(ushort scc, ushort bd){
        volatile ushort status;
#ifdef STBUG
        return;
#endif
        if(!(SCM(scc)&SCCM_ENT)){
                return;
                tx_start(scc);
        }
        status = SCC_TXBD_1W(scc,bd);
        while(status & 0x8000) {
                status = SCC_TXBD_1W(scc,bd);
        }
}
static int startup(struct m68k_serial * info)
{
        unsigned long flags;
 
        if (info->flags & S_INITIALIZED)
                return 0;
 
        if (!info->xmit_buf) {
                info->xmit_buf = (unsigned char *) get_free_page(GFP_KERNEL);
                if (!info->xmit_buf)
                        return -ENOMEM;
        }
        save_flags(flags); cli();
#ifdef SERIAL_DEBUG_OPEN
        printk("starting up ttyS%d (irq %d)...\n", info->line, info->irq);
#endif
        /*
         * Clear the FIFO buffers and disable them
         * (they will be reenabled in change_speed())
         */
 
        if (info->tty)
                clear_bit(TTY_IO_ERROR, &info->tty->flags);
        info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
 
        /*
         * and set the speed of the serial port
         */
 
        scc68302_init();
        SET_INTS_MODE(1);
        change_speed(info);
//      scc0_start_rx(0,rx_buffer, 3,1);
//      rx_start(0);
//      scc_irq_enable(0);
 
        info->flags |= S_INITIALIZED;
        restore_flags(flags);
        return 0;
}
 
/*
 * 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 m68k_serial * info)
{
        unsigned long   flags;
 
        scc_irq_disable(0);
        tx_stop(0); /* All off! */
        rx_stop(0); /* All off! */
        if (!(info->flags & S_INITIALIZED))
                return;
 
#ifdef SERIAL_DEBUG_OPEN
        printk("Shutting down serial port %d (irq %d)....\n", info->line,
               info->irq);
#endif
 
        save_flags(flags); cli(); /* Disable interrupts */
 
        if (info->xmit_buf) {
                free_page((unsigned long) info->xmit_buf);
                info->xmit_buf = 0;
        }
 
        if (info->tty)
                set_bit(TTY_IO_ERROR, &info->tty->flags);
 
        info->flags &= ~S_INITIALIZED;
        restore_flags(flags);
}
 
struct {
        int divisor, prescale;
} hw_baud_table[18] = {
        {0,0}, /* 0 */
        {0,0}, /* 50 */
        {0,0}, /* 75 */
        {0,0}, /* 110 */
        {0,0}, /* 134 */
        {0,0}, /* 150 */
        {0,0}, /* 200 */
        {7,0x26}, /* 300 */
        {6,0x26}, /* 600 */
        {5,0x26}, /* 1200 */
        {0,0}, /* 1800 */
        {4,0x26}, /* 2400 */
        {3,0x26}, /* 4800 */
        {2,0x26}, /* 9600 */
        {1,0x26}, /* 19200 */
        {0,0x26}, /* 38400 */
        {1,0x38}, /* 57600 */
        {0,0x38}, /* 115200 */
};
/* rate = 1036800 / ((65 - prescale) * (1<<divider)) */
 
static int baud_table[] = {
        0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
        9600, 19200, 38400, 57600, 115200, 0 };
 
/*
 * 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 m68k_serial *info)
{
        unsigned short port;
        unsigned cflag;
        int     i;
 
        if (!info->tty || !info->tty->termios)
                return;
        cflag = info->tty->termios->c_cflag;
        if (!(port = info->port))
                return;
 
        /* First disable the interrupts */
        scc_irq_disable(0);
        tx_stop(0);
        rx_stop(0);
        /* set the baudrate */
        i = cflag & CBAUD;
 
        info->baud = baud_table[i];
        scc68302_speed(info->baud, cflag);
        scc0_start_rx(0,rx_buffer, 3,1);
        if(m68k_use_ints){
                tx_start(0);
                rx_start(0);
                scc_irq_enable(0);
        }
        return;
}
 
 
void scc0_start_rx(char bd, char *p_start, ushort size, char last){
#if 0   
        ulong scc_rx_bd_addr;
        ulong  scc_rx_bd_ctrl;
        scc_rx_bd_addr = SCC_BASE + bd * SCC_BD_SIZE * 2 + 4;
        scc_rx_bd_ctrl = SCC_BASE + bd * SCC_BD_SIZE * 2;
 
        *((ulong *)scc_rx_bd_addr) = ( ulong )p_start ; /* adresse reception caratere dans RECEPT*/
        if (last){
                *((ushort *)scc_rx_bd_ctrl) = 0xE000; /* last buffer, start reception */
        }else{
                *((ushort *)scc_rx_bd_ctrl) = 0xC000; /* chained buffer, start reception */
        }
#else
        SCC_RXBD_1L(0,bd) = (ulong)p_start;
        if (last)
                SCC_RXBD_1W(0,bd) = 0xF000;  /* last buffer, start reception */
        else
                SCC_RXBD_1W(0,bd) = 0xD000;  /* chained buffer, start reception */
 
#endif  
}
static void scc0_xmit_char(char ch){
        prompt0 = ch;
        SCC_TXBD_2W(0,0) = (ushort)1; /* nbr de caracteres � emettre */
        SCC_TXBD_1L(0,0) = ( ulong )&prompt0; /* envoi contenu de recept */
        if(m68k_use_ints){
                SCC_TXBD_1W(0,0)= 0xF200; /* start emission */
        }else{
                SCC_TXBD_1W(0,0)= 0xE200; /* start emission */
                scc_wait_EOT(0,0);
        }
}
static void scc0_xmit_string(char *p, int len){
        SCC_TXBD_2W(0,0) = (ushort)len;           /* nbr de caracteres � emettre */
        SCC_TXBD_1L(0,0) = ( ulong )p; /* envoi contenu de recept */
        if(m68k_use_ints){
                SCC_TXBD_1W(0,0)= 0xF200; /* start emission */
        }else{
                SCC_TXBD_1W(0,0) = 0xE200;                /* start emission */
                scc_wait_EOT(0,0);
        }
}
 
#if 0
/* These are for receiving and sending characters under the kgdb
 * source level kernel debugger.
 */
void putDebugChar(char kgdb_char)
{
        struct sun_zschannel *chan = m68k_kgdbchan;
 
        while((chan->control & Tx_BUF_EMP)==0)
                udelay(5);
 
        chan->data = kgdb_char;
}
 
char getDebugChar(void)
{
        struct sun_zschannel *chan = m68k_kgdbchan;
 
        while((chan->control & Rx_CH_AV)==0)
                barrier();
        return chan->data;
}
#endif
 
/*
 * Fair output driver allows a process to speak.
 */
static void rs_fair_output(void)
{
        int left;               /* Output no more than that */
        unsigned long flags;
        struct m68k_serial *info = &m68k_soft;
        char c;
 
        if (info == 0) return;
        if (info->xmit_buf == 0) return;
 
        save_flags(flags);  cli();
        left = info->xmit_cnt;
        while (left != 0) {
                c = info->xmit_buf[info->xmit_tail];
                info->xmit_tail = (info->xmit_tail+1) & (SERIAL_XMIT_SIZE-1);
                info->xmit_cnt--;
                restore_flags(flags);
 
                rs_put_char(c);
 
                save_flags(flags);  cli();
                left = MIN(info->xmit_cnt, left-1);
        }
 
        /* Last character is being transmitted now (hopefully). */
//      udelay(20);
        scc_wait_EOT(0,0);
        restore_flags(flags);
        return;
}
 
/*
 * m68k_console_print is registered for printk.
 */
void console_print_68302(const char *p)
{
        char c;
        struct m68k_serial *info;
        info = &m68k_soft;
 
        if (!(info->flags & S_INITIALIZED)){
                scc68302_init();
                scc68302_speed(9600,0xffff);
        }
        while((c=*(p++)) != 0) {
                if(c == '\n')
                        rs_put_char('\r');
                rs_put_char(c);
        }
 
        /* Comment this if you want to have a strict interrupt-driven output */
        if (!m68k_use_ints)
                rs_fair_output();
 
        return;
}
 
static void rs_set_ldisc(struct tty_struct *tty)
{
        struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 
        if (serial_paranoia_check(info, tty->device, "rs_set_ldisc"))
                return;
 
        info->is_cons = (tty->termios->c_line == N_TTY);
 
        printk("ttyS%d console mode %s\n", info->line, info->is_cons ? "on" : "off");
}
 
static void rs_flush_chars(struct tty_struct *tty)
{
        struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_flush_chars"))
                return;
        if(!m68k_use_ints){
                for(;;) {
                        if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
                                !info->xmit_buf)
                                return;
 
                        /* Enable transmitter */
                        save_flags(flags); cli();
                        tx_start(0);
                }
        }else{
                if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
                        !info->xmit_buf)
                        return;
 
                        /* Enable transmitter */
                save_flags(flags); cli();
                tx_start(0);
        }
 
        if(!m68k_use_ints)
                scc_wait_EOT(0,0);
                /* Send char */
        scc0_xmit_char( info->xmit_buf[info->xmit_tail++]);
        info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
        info->xmit_cnt--;
 
        restore_flags(flags);
}
 
extern void console_printn(const char * b, int count);
 
static int rs_write(struct tty_struct * tty, int from_user,
                    const unsigned char *buf, int count)
{
        int     c, total = 0;
        struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
        unsigned long flags;
 
        if (serial_paranoia_check(info, tty->device, "rs_write"))
                return 0;
 
        if (!tty || !info->xmit_buf)
                return 0;
 
        /*buf = "123456";
        count = 6;
 
        printk("Writing '%s' to serial port\n", buf);*/
 
        /*printk("rs_write of %d bytes\n", count);*/
 
 
        save_flags(flags);
        while (1) {
                cli();
                c = MIN(count, MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
                                   SERIAL_XMIT_SIZE - info->xmit_head));
                if (c <= 0)
                        break;
 
                if (from_user) {
                        down(&tmp_buf_sem);
                        memcpy_fromfs(tmp_buf, buf, c);
                        c = MIN(c, MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
                                       SERIAL_XMIT_SIZE - info->xmit_head));
                        memcpy(info->xmit_buf + info->xmit_head, tmp_buf, c);
                        up(&tmp_buf_sem);
                } else
                        memcpy(info->xmit_buf + info->xmit_head, buf, c);
                info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
                info->xmit_cnt += c;
                restore_flags(flags);
                buf += c;
                count -= c;
                total += c;
        }
 
        if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped ){
                /* Enable transmitter */
 
                cli();
                /*printk("Enabling transmitter\n");*/
 
                if(!m68k_use_ints){
                        while(info->xmit_cnt) {
                                scc_wait_EOT(0,0);
                                /* Send char */
                                scc0_xmit_char(info->xmit_buf[info->xmit_tail++]);
                                scc_wait_EOT(0,0);
                                info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
                                info->xmit_cnt--;
                        }
                }else{
                        if (info->xmit_cnt){
                                /* Send char */
                                scc_wait_EOT(0,0);
                                // xmit_string should be use instead
                                scc0_xmit_char(info->xmit_buf[info->xmit_tail++]);
                                info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
                                info->xmit_cnt--;
                        }
                }
                restore_flags(flags);
        } else {
                /*printk("Skipping transmit\n");*/
        }
 
 
#if 0
                printk("Enabling stuff anyhow\n");
                tx_start(0);
 
                if (SCC_EOT(0,0)) {
                        printk("TX FIFO empty.\n");
                        /* Send char */
                        scc0_xmit_char(info->xmit_buf[info->xmit_tail++]);
                        info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
                        info->xmit_cnt--;
                }
#endif
 
        restore_flags(flags);
        return total;
}
 
static int rs_write_room(struct tty_struct *tty)
{
        struct m68k_serial *info = (struct m68k_serial *)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 m68k_serial *info = (struct m68k_serial *)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 m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 
        if (serial_paranoia_check(info, tty->device, "rs_flush_buffer"))
                return;
        cli();
        info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
        sti();
        wake_up_interruptible(&tty->write_wait);
        if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
            tty->ldisc.write_wakeup)
                (tty->ldisc.write_wakeup)(tty);
}
 
/*
 * ------------------------------------------------------------
 * 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 m68k_serial *info = (struct m68k_serial *)tty->driver_data;
#ifdef SERIAL_DEBUG_THROTTLE
        char    buf[64];
 
        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))
                info->x_char = STOP_CHAR(tty);
 
        /* Turn off RTS line (do this atomic) */
}
 
static void rs_unthrottle(struct tty_struct * tty)
{
        struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
#ifdef SERIAL_DEBUG_THROTTLE
        char    buf[64];
 
        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
                        info->x_char = START_CHAR(tty);
        }
 
        /* Assert RTS line (do this atomic) */
}
 
/*
 * ------------------------------------------------------------
 * rs_ioctl() and friends
 * ------------------------------------------------------------
 */
 
static int get_serial_info(struct m68k_serial * info,
                           struct serial_struct * retinfo)
{
        struct serial_struct tmp;
 
        if (!retinfo)
                return -EFAULT;
        memset(&tmp, 0, sizeof(tmp));
        tmp.type = info->type;
        tmp.line = info->line;
        tmp.port = info->port;
        tmp.irq = info->irq;
        tmp.flags = info->flags;
        tmp.baud_base = info->baud_base;
        tmp.close_delay = info->close_delay;
        tmp.closing_wait = info->closing_wait;
        tmp.custom_divisor = info->custom_divisor;
        memcpy_tofs(retinfo,&tmp,sizeof(*retinfo));
        return 0;
}
 
static int set_serial_info(struct m68k_serial * info,
                           struct serial_struct * new_info)
{
        struct serial_struct new_serial;
        struct m68k_serial old_info;
        int                     retval = 0;
 
        if (!new_info)
                return -EFAULT;
        memcpy_fromfs(&new_serial,new_info,sizeof(new_serial));
        old_info = *info;
 
        if (!suser()) {
                if ((new_serial.baud_base != info->baud_base) ||
                    (new_serial.type != info->type) ||
                    (new_serial.close_delay != info->close_delay) ||
                    ((new_serial.flags & ~S_USR_MASK) !=
                     (info->flags & ~S_USR_MASK)))
                        return -EPERM;
                info->flags = ((info->flags & ~S_USR_MASK) |
                               (new_serial.flags & S_USR_MASK));
                info->custom_divisor = new_serial.custom_divisor;
                goto check_and_exit;
        }
 
        if (info->count > 1)
                return -EBUSY;
 
        /*
         * OK, past this point, all the error checking has been done.
         * At this point, we start making changes.....
         */
 
        info->baud_base = new_serial.baud_base;
        info->flags = ((info->flags & ~S_FLAGS) |
                        (new_serial.flags & S_FLAGS));
        info->type = new_serial.type;
        info->close_delay = new_serial.close_delay;
        info->closing_wait = new_serial.closing_wait;
 
check_and_exit:
        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 m68k_serial * info, unsigned int *value)
{
        unsigned char status;
 
        cli();
        if(m68k_use_ints)
                status = (SCC_EOT(0,0))? 1 : 0;
        else
                status = 0;
        sti();
        put_user(status,value);
        return 0;
}
 
/*
 * This routine sends a break character out the serial port.
 */
static void send_break( struct m68k_serial * info, int duration)
{
        if (!info->port)
                return;
        current->state = TASK_INTERRUPTIBLE;
        current->timeout = jiffies + duration;
        cli();
        if(m68k_use_ints)
                scc_cmd(0,CR_OP_STOP_TX);
        sti();
}
 
static int rs_ioctl(struct tty_struct *tty, struct file * file,
                    unsigned int cmd, unsigned long arg)
{
        int error;
        struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
        int retval;
 
        if (serial_paranoia_check(info, tty->device, "rs_ioctl"))
                return -ENODEV;
 
        if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
            (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD)  &&
            (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
                if (tty->flags & (1 << TTY_IO_ERROR))
                    return -EIO;
        }
 
        switch (cmd) {
                case TCSBRK:    /* SVID version: non-zero arg --> no break */
                        retval = tty_check_change(tty);
                        if (retval)
                                return retval;
                        tty_wait_until_sent(tty, 0);
                        if (!arg)
                                send_break(info, HZ/4); /* 1/4 second */
                        return 0;
                case TCSBRKP:   /* support for POSIX tcsendbreak() */
                        retval = tty_check_change(tty);
                        if (retval)
                                return retval;
                        tty_wait_until_sent(tty, 0);
                        send_break(info, arg ? arg*(HZ/10) : HZ/4);
                        return 0;
                case TIOCGSOFTCAR:
                        error = verify_area(VERIFY_WRITE, (void *) arg,sizeof(long));
                        if (error)
                                return error;
                        put_fs_long(C_CLOCAL(tty) ? 1 : 0,
                                    (unsigned long *) arg);
                        return 0;
                case TIOCSSOFTCAR:
                        arg = get_fs_long((unsigned long *) arg);
                        tty->termios->c_cflag =
                                ((tty->termios->c_cflag & ~CLOCAL) |
                                 (arg ? CLOCAL : 0));
                        return 0;
                case TIOCGSERIAL:
                        error = verify_area(VERIFY_WRITE, (void *) arg,
                                                sizeof(struct serial_struct));
                        if (error)
                                return error;
                        return get_serial_info(info,
                                               (struct serial_struct *) arg);
                case TIOCSSERIAL:
                        return set_serial_info(info,
                                               (struct serial_struct *) arg);
                case TIOCSERGETLSR: /* Get line status register */
                        error = verify_area(VERIFY_WRITE, (void *) arg,
                                sizeof(unsigned int));
                        if (error)
                                return error;
                        else
                            return get_lsr_info(info, (unsigned int *) arg);
 
                case TIOCSERGSTRUCT:
                        error = verify_area(VERIFY_WRITE, (void *) arg,
                                                sizeof(struct m68k_serial));
                        if (error)
                                return error;
                        memcpy_tofs((struct m68k_serial *) arg,
                                    info, sizeof(struct m68k_serial));
                        return 0;
 
                default:
                        return -ENOIOCTLCMD;
                }
        return 0;
}
 
static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
{
        struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
 
        if (tty->termios->c_cflag == old_termios->c_cflag)
                return;
 
        change_speed(info);
 
        if ((old_termios->c_cflag & CRTSCTS) &&
            !(tty->termios->c_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
 * S 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 m68k_serial * info = (struct m68k_serial *)tty->driver_data;
        unsigned long flags;
 
        if (!info || serial_paranoia_check(info, tty->device, "rs_close"))
                return;
 
        save_flags(flags); cli();
 
        if (tty_hung_up_p(filp)) {
                restore_flags(flags);
                return;
        }
 
#ifdef SERIAL_DEBUG_OPEN
        printk("rs_close ttyS%d, count = %d\n", info->line, info->count);
#endif
        if ((tty->count == 1) && (info->count != 1)) {
                /*
                 * Uh, oh.  tty->count is 1, which means that the tty
                 * structure will be freed.  Info->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.
                 */
                printk("rs_close: bad serial port count; tty->count is 1, "
                       "info->count is %d\n", info->count);
                info->count = 1;
        }
        if (--info->count < 0) {
                printk("rs_close: bad serial port count for ttyS%d: %d\n",
                       info->line, info->count);
                info->count = 0;
        }
        if (info->count) {
                restore_flags(flags);
                return;
        }
        // closing port so disable SCC interrupts
        SET_INTS_MODE(0);
 
        info->flags |= S_CLOSING;
        /*
         * Save the termios structure, since this port may have
         * separate termios for callout and dialin.
         */
        if (info->flags & S_NORMAL_ACTIVE)
                info->normal_termios = *tty->termios;
        if (info->flags & S_CALLOUT_ACTIVE)
                info->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 != S_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.
         */
 
        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 (tty->ldisc.num != ldiscs[N_TTY].num) {
                if (tty->ldisc.close)
                        (tty->ldisc.close)(tty);
                tty->ldisc = ldiscs[N_TTY];
                tty->termios->c_line = N_TTY;
                if (tty->ldisc.open)
                        (tty->ldisc.open)(tty);
        }
        if (info->blocked_open) {
                if (info->close_delay) {
                        current->state = TASK_INTERRUPTIBLE;
                        current->timeout = jiffies + info->close_delay;
                        schedule();
                }
                wake_up_interruptible(&info->open_wait);
        }
        info->flags &= ~(S_NORMAL_ACTIVE|S_CALLOUT_ACTIVE|
                         S_CLOSING);
        wake_up_interruptible(&info->close_wait);
        restore_flags(flags);
}
 
/*
 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
 */
void rs_hangup(struct tty_struct *tty)
{
        struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
 
        if (serial_paranoia_check(info, tty->device, "rs_hangup"))
                return;
 
        rs_flush_buffer(tty);
        shutdown(info);
        info->event = 0;
        info->count = 0;
        info->flags &= ~(S_NORMAL_ACTIVE|S_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 m68k_serial *info)
{
        struct wait_queue wait = { current, NULL };
        int             retval;
        int             do_clocal = 0;
 
        /*
         * If the device is in the middle of being closed, then block
         * until it's done, and then try again.
         */
        if (info->flags & S_CLOSING) {
                interruptible_sleep_on(&info->close_wait);
#ifdef SERIAL_DO_RESTART
                if (info->flags & S_HUP_NOTIFY)
                        return -EAGAIN;
                else
                        return -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 & S_NORMAL_ACTIVE)
                        return -EBUSY;
                if ((info->flags & S_CALLOUT_ACTIVE) &&
                    (info->flags & S_SESSION_LOCKOUT) &&
                    (info->session != current->session))
                    return -EBUSY;
                if ((info->flags & S_CALLOUT_ACTIVE) &&
                    (info->flags & S_PGRP_LOCKOUT) &&
                    (info->pgrp != current->pgrp))
                    return -EBUSY;
                info->flags |= S_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 & S_CALLOUT_ACTIVE)
                        return -EBUSY;
                info->flags |= S_NORMAL_ACTIVE;
                return 0;
        }
 
        if (info->flags & S_CALLOUT_ACTIVE) {
                if (info->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, info->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
        printk("block_til_ready before block: ttyS%d, count = %d\n",
               info->line, info->count);
#endif
        info->count--;
        info->blocked_open++;
        while (1) {
                cli();
                if (!(info->flags & S_CALLOUT_ACTIVE))
                        m68k_rtsdtr(info, 1);
                sti();
                current->state = TASK_INTERRUPTIBLE;
                if (tty_hung_up_p(filp) ||
                    !(info->flags & S_INITIALIZED)) {
#ifdef SERIAL_DO_RESTART
                        if (info->flags & S_HUP_NOTIFY)
                                retval = -EAGAIN;
                        else
                                retval = -ERESTARTSYS;
#else
                        retval = -EAGAIN;
#endif
                        break;
                }
                if (!(info->flags & S_CALLOUT_ACTIVE) &&
                    !(info->flags & S_CLOSING) && do_clocal)
                        break;
                if (current->signal & ~current->blocked) {
                        retval = -ERESTARTSYS;
                        break;
                }
#ifdef SERIAL_DEBUG_OPEN
                printk("block_til_ready blocking: ttyS%d, count = %d\n",
                       info->line, info->count);
#endif
                schedule();
        }
        current->state = TASK_RUNNING;
        remove_wait_queue(&info->open_wait, &wait);
        if (!tty_hung_up_p(filp))
                info->count++;
        info->blocked_open--;
#ifdef SERIAL_DEBUG_OPEN
        printk("block_til_ready after blocking: ttyS%d, count = %d\n",
               info->line, info->count);
#endif
        if (retval)
                return retval;
        info->flags |= S_NORMAL_ACTIVE;
        if(!m68k_use_ints)
                queue_task(&serialpoll, &tq_timer);
        return 0;
}
 
/*
 * This routine is called whenever a serial port is opened.  It
 * enables interrupts for a serial port, linking in its S structure into
 * the IRQ chain.   It also performs the serial-specific
 * initialization for the tty structure.
 */
int rs_open(struct tty_struct *tty, struct file * filp)
{
        struct m68k_serial      *info;
        int                     retval, line;
 
        line = MINOR(tty->device) - tty->driver.minor_start;
 
        if (line != 0) /* we have exactly one */
                return -ENODEV;
 
        info = &m68k_soft;
#if 0
        /* Is the kgdb running over this line? */
        if (info->kgdb_channel)
                return -ENODEV;
#endif
        if (serial_paranoia_check(info, tty->device, "rs_open"))
                return -ENODEV;
#ifdef SERIAL_DEBUG_OPEN
        printk("rs_open %s%d, count = %d\n", tty->driver.name, info->line,
               info->count);
#endif
        info->count++;
        tty->driver_data = info;
        info->tty = tty;
 
        /*
         * Start up serial port
         */
        retval = startup(info);
        if (retval)
                return retval;
 
        retval = block_til_ready(tty, filp, info);
        if (retval) {
#ifdef SERIAL_DEBUG_OPEN
                printk("rs_open returning after block_til_ready with %d\n",
                       retval);
#endif
                return retval;
        }
 
        if ((info->count == 1) && (info->flags & S_SPLIT_TERMIOS)) {
                if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
                        *tty->termios = info->normal_termios;
                else
                        *tty->termios = info->callout_termios;
                change_speed(info);
        }
 
        info->session = current->session;
        info->pgrp = current->pgrp;
 
#ifdef SERIAL_DEBUG_OPEN
        printk("rs_open ttyS%d successful...\n", info->line);
#endif
        return 0;
}
 
/* Finally, routines used to initialize the serial driver. */
 
static void show_serial_version(void)
{
        printk("MC68302 serial driver version 1.00\n");
}
 
extern void register_console(void (*proc)(const char *));
#if 0
 
static inline void
rs_cons_check(struct m68k_serial *ss, int channel)
{
        int i, o, io;
        static consout_registered = 0;
        static msg_printed = 0;
 
        i = o = io = 0;
 
        /* Is this one of the serial console lines? */
        if((m68k_cons_chanout != channel) &&
           (m68k_cons_chanin != channel))
                return;
        m68k_conschan = ss->m68k_channel;
        m68k_consinfo = ss;
 
        /* Register the console output putchar, if necessary */
        if((m68k_cons_chanout == channel)) {
                o = 1;
                /* double whee.. */
                if(!consout_registered) {
                        register_console(m68k_console_print);
                        consout_registered = 1;
                }
        }
 
        /* If this is console input, we handle the break received
         * status interrupt on this line to mean prom_halt().
         */
        if(m68k_cons_chanin == channel) {
                ss->break_abort = 1;
                i = 1;
        }
        if(o && i)
                io = 1;
        if(ss->m68k_baud != 9600)
                panic("Console baud rate weirdness");
 
        /* Set flag variable for this port so that it cannot be
         * opened for other uses by accident.
         */
        ss->is_cons = 1;
 
        if(io) {
                if(!msg_printed) {
                        printk("zs%d: console I/O\n", ((channel>>1)&1));
                        msg_printed = 1;
                }
        } else {
                printk("zs%d: console %s\n", ((channel>>1)&1),
                       (i==1 ? "input" : (o==1 ? "output" : "WEIRD")));
        }
}
#endif
 
volatile int test_done;
 
/* rs_init inits the driver */
int rs68302_init(void)
{
        int flags;
        struct m68k_serial *info;
        m68k_use_ints=0;
        /* Setup base handler, and timer table. */
        init_bh(SERIAL_BH, do_serial_bh);
        timer_table[RS_TIMER].fn = rs_timer;
        timer_table[RS_TIMER].expires = 0;
 
        /* Initialize the tty_driver structure */
 
        memset(&serial_driver, 0, sizeof(struct tty_driver));
        serial_driver.magic = TTY_DRIVER_MAGIC;
        serial_driver.name = "ttyS";
        serial_driver.major = TTY_MAJOR;
        serial_driver.minor_start = 64;
        serial_driver.num = 1;
        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.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.set_termios = rs_set_termios;
        serial_driver.stop = rs_stop;
        serial_driver.start = rs_start;
        serial_driver.hangup = rs_hangup;
        serial_driver.set_ldisc = rs_set_ldisc;
 
        /*
         * 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;
 
        if (tty_register_driver(&serial_driver))
                panic("Couldn't register serial driver\n");
        if (tty_register_driver(&callout_driver))
                panic("Couldn't register callout driver\n");
 
        save_flags(flags); cli();
 
        info = &m68k_soft;
        info->magic = SERIAL_MAGIC;
        info->port = 1;
        info->tty = 0;
        info->irq = 0;   /* SCC1 irq;*/
        info->custom_divisor = 16;
        info->close_delay = 50;
        info->closing_wait = 3000;
        info->x_char = 0;
        info->event = 0;
        info->count = 0;
        info->blocked_open = 0;
        info->tqueue.routine = do_softint;
        info->tqueue.data = info;
        info->tqueue_hangup.routine = do_serial_hangup;
        info->tqueue_hangup.data = info;
        info->callout_termios =callout_driver.init_termios;
        info->normal_termios = serial_driver.init_termios;
        info->open_wait = 0;
        info->close_wait = 0;
        info->line = 0;
        info->is_cons = 1; /* Means shortcuts work */
#if 0
        if (request_irq(scc_irq,
                                        rs_interrupt,
                                        (SA_INTERRUPT | SA_STATIC_ALLOC),
                                        "68302 SCC", NULL))
                panic("Unable to attach scc intr\n");
#endif
 
        restore_flags(flags);
// hack to do polling
        serialpoll.routine = serpoll;
        serialpoll.data = (void *)&m68k_soft;
 
        return 0;
}
 
/*
 * register_serial and unregister_serial allows for serial ports to be
 * configured at run-time, to support PCMCIA modems.
 */
/* SPARC: Unused at this time, just here to make things link. */
int register_serial(struct serial_struct *req)
{
        return -1;
}
 
void unregister_serial(int line)
{
        return;
}
 
#if 0
/* Hooks for running a serial console.  con_init() calls this if the
 * console is being run over one of the ttya/ttyb serial ports.
 * 'chip' should be zero, as chip 1 drives the mouse/keyboard.
 * 'channel' is decoded as 0=TTYA 1=TTYB, note that the channels
 * are addressed backwards, channel B is first, then channel A.
 */
void
rs_cons_hook(int chip, int out, int channel)
{
        if(chip)
                panic("rs_cons_hook called with chip not zero");
        if(!m68k_chips[chip]) {
                m68k_chips[chip] = get_zs(chip);
                /* Two channels per chip */
                m68k_channels[(chip*2)] = &m68k_chips[chip]->channelA;
                m68k_channels[(chip*2)+1] = &m68k_chips[chip]->channelB;
        }
        m68k_soft[channel].m68k_channel = m68k_channels[channel];
        m68k_soft[channel].change_needed = 0;
        m68k_soft[channel].clk_divisor = 16;
        m68k_soft[channel].m68k_baud = get_zsbaud(&m68k_soft[channel]);
        rs_cons_check(&m68k_soft[channel], channel);
        if(out)
                m68k_cons_chanout = ((chip * 2) + channel);
        else
                m68k_cons_chanin = ((chip * 2) + channel);
 
}
 
/* This is called at boot time to prime the kgdb serial debugging
 * serial line.  The 'tty_num' argument is 0 for /dev/ttya and 1
 * for /dev/ttyb which is determined in setup_arch() from the
 * boot command line flags.
 */
void
rs_kgdb_hook(int tty_num)
{
        int chip = 0;
 
        if(!m68k_chips[chip]) {
                m68k_chips[chip] = get_zs(chip);
                /* Two channels per chip */
                m68k_channels[(chip*2)] = &m68k_chips[chip]->channelA;
                m68k_channels[(chip*2)+1] = &m68k_chips[chip]->channelB;
        }
        m68k_soft[tty_num].m68k_channel = m68k_channels[tty_num];
        m68k_kgdbchan = m68k_soft[tty_num].m68k_channel;
        m68k_soft[tty_num].change_needed = 0;
        m68k_soft[tty_num].clk_divisor = 16;
        m68k_soft[tty_num].m68k_baud = get_zsbaud(&m68k_soft[tty_num]);
        m68k_soft[tty_num].kgdb_channel = 1;     /* This runs kgdb */
        m68k_soft[tty_num ^ 1].kgdb_channel = 0; /* This does not */
        /* Turn on transmitter/receiver at 8-bits/char */
        kgdb_chaninit(&m68k_soft[tty_num], 0, 9600);
        ZS_CLEARERR(m68k_kgdbchan);
        udelay(5);
        ZS_CLEARFIFO(m68k_kgdbchan);
}
#endif
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[/] [or1k/] [trunk/] [rc203soc/] [sw/] [uClinux/] [drivers/] [char/] [68302serial.c] - Blame information for rev 1765

Line No.	Rev	Author	Line
1	1626	jcastillo	`/* 68302serial.c: Serial port driver for 68302 microcontroller`
2			`*`
3			`* Based on:`
4			`*`
5			`* drivers/char/68328serial.c`
6			`*/`
7
8			`#include <linux/errno.h>`
9			`#include <linux/signal.h>`
10			`#include <linux/sched.h>`
11			`#include <linux/timer.h>`
12			`#include <linux/interrupt.h>`
13			`#include <linux/tty.h>`
14			`#include <linux/tty_flip.h>`
15			`#include <linux/config.h>`
16			`#include <linux/major.h>`
17			`#include <linux/string.h>`
18			`#include <linux/fcntl.h>`
19			`#include <linux/mm.h>`
20			`#include <linux/kernel.h>`
21
22			`#include <asm/io.h>`
23			`#include <asm/irq.h>`
24			`#include <asm/system.h>`
25			`#include <asm/segment.h>`
26			`#include <asm/bitops.h>`
27			`#include <asm/delay.h>`
28			`#if 0`
29			`#include <asm/kdebug.h>`
30			`#endif`
31
32			`#include "68302serial.h"`
33
34			`#define USE_INTS 1`
35			`//#undef USE_INTS`
36			`#undef USE_ONLY_RX_INTS`
37
38			`static int m68k_use_ints=0;`
39			`#define SET_INTS_MODE(x) m68k_use_ints=x`
40