amiserial.c

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/*
 * ------------------------------------------------------------
 * rs_open() and friends
 * ------------------------------------------------------------
 */
static int block_til_ready(struct tty_struct *tty, struct file * filp,
			   struct async_struct *info)
{
#ifdef DECLARE_WAITQUEUE
	DECLARE_WAITQUEUE(wait, current);
#else
	struct wait_queue wait = { current, NULL };
#endif
	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 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))) {
		info->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}

	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
	printk("block_til_ready before block: ttys%d, count = %d\n",
	       state->line, state->count);
#endif
	local_irq_save(flags);
	if (!tty_hung_up_p(filp)) {
		extra_count = 1;
		state->count--;
	}
	local_irq_restore(flags);
	info->blocked_open++;
	while (1) {
		local_irq_save(flags);
		if (tty->termios->c_cflag & CBAUD)
		        rtsdtr_ctrl(SER_DTR|SER_RTS);
		local_irq_restore(flags);
		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_CLOSING) &&
		    (do_clocal || (!(ciab.pra & SER_DCD)) ))
			break;
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
#ifdef SERIAL_DEBUG_OPEN
		printk("block_til_ready blocking: ttys%d, count = %d\n",
		       info->line, state->count);
#endif
		schedule();
	}
	__set_current_state(TASK_RUNNING);
	remove_wait_queue(&info->open_wait, &wait);
	if (extra_count)
		state->count++;
	info->blocked_open--;
#ifdef SERIAL_DEBUG_OPEN
	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 = kzalloc(sizeof(struct async_struct), GFP_KERNEL);
	if (!info) {
		sstate->count--;
		return -ENOMEM;
	}
#ifdef DECLARE_WAITQUEUE
	init_waitqueue_head(&info->open_wait);
	init_waitqueue_head(&info->close_wait);
	init_waitqueue_head(&info->delta_msr_wait);
#endif
	info->magic = SERIAL_MAGIC;
	info->port = sstate->port;
	info->flags = sstate->flags;
	info->xmit_fifo_size = sstate->xmit_fifo_size;
	info->line = line;
	tasklet_init(&info->tlet, do_softint, (unsigned long)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;

	line = tty->index;
	if ((line < 0) || (line >= NR_PORTS)) {
		return -ENODEV;
	}
	retval = get_async_struct(line, &info);
	if (retval) {
		return retval;
	}
	tty->driver_data = info;
	info->tty = tty;
	if (serial_paranoia_check(info, tty->name, "rs_open"))
		return -ENODEV;

#ifdef SERIAL_DEBUG_OPEN
	printk("rs_open %s, count = %d\n", tty->name, info->state->count);
#endif
	info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;

	/*
	 * 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);
#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) {
		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;
	}

#ifdef SERIAL_DEBUG_OPEN
	printk("rs_open %s successful...", tty->name);
#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;
	char	stat_buf[30], control, status;
	int	ret;
	unsigned long flags;

	ret = sprintf(buf, "%d: uart:amiga_builtin",state->line);

	/*
	 * Figure out the current RS-232 lines
	 */
	if (!info) {
		info = &scr_info;	/* This is just for serial_{in,out} */

		info->magic = SERIAL_MAGIC;
		info->flags = state->flags;
		info->quot = 0;
		info->tty = NULL;
	}
	local_irq_save(flags);
	status = ciab.pra;
	control = info ? info->MCR : status;
	local_irq_restore(flags);

	stat_buf[0] = 0;
	stat_buf[1] = 0;
	if(!(control & SER_RTS))
		strcat(stat_buf, "|RTS");
	if(!(status & SER_CTS))
		strcat(stat_buf, "|CTS");
	if(!(control & SER_DTR))
		strcat(stat_buf, "|DTR");
	if(!(status & SER_DSR))
		strcat(stat_buf, "|DSR");
	if(!(status & SER_DCD))
		strcat(stat_buf, "|CD");

	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);

	/*
	 * Last thing is the RS-232 status lines
	 */
	ret += sprintf(buf+ret, " %s\n", stat_buf+1);
	return ret;
}

static int rs_read_proc(char *page, char **start, off_t off, int count,
			int *eof, void *data)
{
	int len = 0, l;
	off_t	begin = 0;

	len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version);
	l = line_info(page + len, &rs_table[0]);
	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 void show_serial_version(void)
{
 	printk(KERN_INFO "%s version %s\n", serial_name, serial_version);
}


static const struct tty_operations serial_ops = {
	.open = rs_open,
	.close = rs_close,
	.write = rs_write,
	.put_char = rs_put_char,
	.flush_chars = rs_flush_chars,
	.write_room = rs_write_room,
	.chars_in_buffer = rs_chars_in_buffer,
	.flush_buffer = rs_flush_buffer,
	.ioctl = rs_ioctl,
	.throttle = rs_throttle,
	.unthrottle = rs_unthrottle,
	.set_termios = rs_set_termios,
	.stop = rs_stop,
	.start = rs_start,
	.hangup = rs_hangup,
	.break_ctl = rs_break,
	.send_xchar = rs_send_xchar,
	.wait_until_sent = rs_wait_until_sent,
	.read_proc = rs_read_proc,
	.tiocmget = rs_tiocmget,
	.tiocmset = rs_tiocmset,
};

/*
 * The serial driver boot-time initialization code!
 */
static int __init rs_init(void)
{
	unsigned long flags;
	struct serial_state * state;

	if (!MACH_IS_AMIGA || !AMIGAHW_PRESENT(AMI_SERIAL))
		return -ENODEV;

	serial_driver = alloc_tty_driver(1);
	if (!serial_driver)
		return -ENOMEM;

	/*
	 *  We request SERDAT and SERPER only, because the serial registers are
	 *  too spreaded over the custom register space
	 */
	if (!request_mem_region(CUSTOM_PHYSADDR+0x30, 4, "amiserial [Paula]"))
		return -EBUSY;

	IRQ_ports = NULL;

	show_serial_version();

	/* Initialize the tty_driver structure */

	serial_driver->owner = THIS_MODULE;
	serial_driver->driver_name = "amiserial";
	serial_driver->name = "ttyS";
	serial_driver->major = TTY_MAJOR;
	serial_driver->minor_start = 64;
	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;
	tty_set_operations(serial_driver, &serial_ops);

	if (tty_register_driver(serial_driver))
		panic("Couldn't register serial driver\n");

	state = rs_table;
	state->magic = SSTATE_MAGIC;
	state->port = (int)&custom.serdatr; /* Just to give it a value */
	state->line = 0;
	state->custom_divisor = 0;
	state->close_delay = 5*HZ/10;
	state->closing_wait = 30*HZ;
	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;

	printk(KERN_INFO "ttyS%d is the amiga builtin serial port\n",
		       state->line);

	/* Hardware set up */

	state->baud_base = amiga_colorclock;
	state->xmit_fifo_size = 1;

	local_irq_save(flags);

	/* set ISRs, and then disable the rx interrupts */
	request_irq(IRQ_AMIGA_TBE, ser_tx_int, 0, "serial TX", state);
	request_irq(IRQ_AMIGA_RBF, ser_rx_int, IRQF_DISABLED, "serial RX", state);

	/* turn off Rx and Tx interrupts */
	custom.intena = IF_RBF | IF_TBE;
	mb();

	/* clear any pending interrupt */
	custom.intreq = IF_RBF | IF_TBE;
	mb();

	local_irq_restore(flags);

	/*
	 * set the appropriate directions for the modem control flags,
	 * and clear RTS and DTR
	 */
	ciab.ddra |= (SER_DTR | SER_RTS);   /* outputs */
	ciab.ddra &= ~(SER_DCD | SER_CTS | SER_DSR);  /* inputs */

	return 0;
}

static __exit void rs_exit(void) 
{
	int error;
	struct async_struct *info = rs_table[0].info;

	/* printk("Unloading %s: version %s\n", serial_name, serial_version); */
	tasklet_kill(&info->tlet);
	if ((error = tty_unregister_driver(serial_driver)))
		printk("SERIAL: failed to unregister serial driver (%d)\n",
		       error);
	put_tty_driver(serial_driver);

	if (info) {
	  rs_table[0].info = NULL;
	  kfree(info);
	}

	release_mem_region(CUSTOM_PHYSADDR+0x30, 4);
}

module_init(rs_init)
module_exit(rs_exit)


/*
 * ------------------------------------------------------------
 * Serial console driver
 * ------------------------------------------------------------
 */
#ifdef CONFIG_SERIAL_CONSOLE

static void amiga_serial_putc(char c)
{
	custom.serdat = (unsigned char)c | 0x100;
	while (!(custom.serdatr & 0x2000))
		barrier();
}

/*
 *	Print a string to the serial port trying not to disturb
 *	any possible real use of the port...
 *
 *	The console must be locked when we get here.
 */
static void serial_console_write(struct console *co, const char *s,
				unsigned count)
{
	unsigned short intena = custom.intenar;

	custom.intena = IF_TBE;

	while (count--) {
		if (*s == '\n')
			amiga_serial_putc('\r');
		amiga_serial_putc(*s++);
	}

	custom.intena = IF_SETCLR | (intena & IF_TBE);
}

static struct tty_driver *serial_console_device(struct console *c, int *index)
{
	*index = 0;
	return serial_driver;
}

static struct console sercons = {
	.name =		"ttyS",
	.write =	serial_console_write,
	.device =	serial_console_device,
	.flags =	CON_PRINTBUFFER,
	.index =	-1,
};

/*
 *	Register console.
 */
static int __init amiserial_console_init(void)
{
	register_console(&sercons);
	return 0;
}
console_initcall(amiserial_console_init);
#endif

MODULE_LICENSE("GPL");