digi_acceleport.c

linux-2.6.15.6

	.num_bulk_out =			4,
	.num_ports =			3,
	.open =				digi_open,
	.close =			digi_close,
	.write =			digi_write,
	.write_room =			digi_write_room,
	.write_bulk_callback = 		digi_write_bulk_callback,
	.read_bulk_callback =		digi_read_bulk_callback,
	.chars_in_buffer =		digi_chars_in_buffer,
	.throttle =			digi_rx_throttle,
	.unthrottle =			digi_rx_unthrottle,
	.ioctl =			digi_ioctl,
	.set_termios =			digi_set_termios,
	.break_ctl =			digi_break_ctl,
	.tiocmget =			digi_tiocmget,
	.tiocmset =			digi_tiocmset,
	.attach =			digi_startup,
	.shutdown =			digi_shutdown,
};

static struct usb_serial_driver digi_acceleport_4_device = {
	.driver = {
		.owner =		THIS_MODULE,
		.name =			"digi_4",
	},
	.description =			"Digi 4 port USB adapter",
	.id_table =			id_table_4,
	.num_interrupt_in =		0,
	.num_bulk_in =			5,
	.num_bulk_out =			5,
	.num_ports =			4,
	.open =				digi_open,
	.close =			digi_close,
	.write =			digi_write,
	.write_room =			digi_write_room,
	.write_bulk_callback = 		digi_write_bulk_callback,
	.read_bulk_callback =		digi_read_bulk_callback,
	.chars_in_buffer =		digi_chars_in_buffer,
	.throttle =			digi_rx_throttle,
	.unthrottle =			digi_rx_unthrottle,
	.ioctl =			digi_ioctl,
	.set_termios =			digi_set_termios,
	.break_ctl =			digi_break_ctl,
	.tiocmget =			digi_tiocmget,
	.tiocmset =			digi_tiocmset,
	.attach =			digi_startup,
	.shutdown =			digi_shutdown,
};


/* Functions */

/*
*  Cond Wait Interruptible Timeout Irqrestore
*
*  Do spin_unlock_irqrestore and interruptible_sleep_on_timeout
*  so that wake ups are not lost if they occur between the unlock
*  and the sleep.  In other words, spin_unlock_irqrestore and
*  interruptible_sleep_on_timeout are "atomic" with respect to
*  wake ups.  This is used to implement condition variables.
*
*  interruptible_sleep_on_timeout is deprecated and has been replaced
*  with the equivalent code.
*/

static inline long cond_wait_interruptible_timeout_irqrestore(
	wait_queue_head_t *q, long timeout,
	spinlock_t *lock, unsigned long flags )
{
	DEFINE_WAIT(wait);

	prepare_to_wait(q, &wait, TASK_INTERRUPTIBLE);
	spin_unlock_irqrestore(lock, flags);
	timeout = schedule_timeout(timeout);
	finish_wait(q, &wait);

	return timeout;
}


/*
*  Digi Wakeup Write
*
*  Wake up port, line discipline, and tty processes sleeping
*  on writes.
*/

static void digi_wakeup_write_lock(void *arg)
{
	struct usb_serial_port *port = arg;
	unsigned long flags;
	struct digi_port *priv = usb_get_serial_port_data(port);


	spin_lock_irqsave( &priv->dp_port_lock, flags );
	digi_wakeup_write( port );
	spin_unlock_irqrestore( &priv->dp_port_lock, flags );
}

static void digi_wakeup_write( struct usb_serial_port *port )
{

	struct tty_struct *tty = port->tty;


	/* wake up port processes */
	wake_up_interruptible( &port->write_wait );

	/* wake up line discipline */
	tty_wakeup(tty);
}


/*
*  Digi Write OOB Command
*
*  Write commands on the out of band port.  Commands are 4
*  bytes each, multiple commands can be sent at once, and
*  no command will be split across USB packets.  Returns 0
*  if successful, -EINTR if interrupted while sleeping and
*  the interruptible flag is true, or a negative error
*  returned by usb_submit_urb.
*/

static int digi_write_oob_command( struct usb_serial_port *port,
	unsigned char *buf, int count, int interruptible )
{

	int ret = 0;
	int len;
	struct usb_serial_port *oob_port = (struct usb_serial_port *)((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
	unsigned long flags = 0;


dbg( "digi_write_oob_command: TOP: port=%d, count=%d", oob_priv->dp_port_num, count );

	spin_lock_irqsave( &oob_priv->dp_port_lock, flags );

	while( count > 0 ) {

		while( oob_port->write_urb->status == -EINPROGRESS
		|| oob_priv->dp_write_urb_in_use ) {
			cond_wait_interruptible_timeout_irqrestore(
				&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
				&oob_priv->dp_port_lock, flags );
			if( interruptible && signal_pending(current) ) {
				return( -EINTR );
			}
			spin_lock_irqsave( &oob_priv->dp_port_lock, flags );
		}

		/* len must be a multiple of 4, so commands are not split */
		len = min(count, oob_port->bulk_out_size );
		if( len > 4 )
			len &= ~3;

		memcpy( oob_port->write_urb->transfer_buffer, buf, len );
		oob_port->write_urb->transfer_buffer_length = len;
		oob_port->write_urb->dev = port->serial->dev;

		if( (ret=usb_submit_urb(oob_port->write_urb, GFP_ATOMIC)) == 0 ) {
			oob_priv->dp_write_urb_in_use = 1;
			count -= len;
			buf += len;
		}

	}

	spin_unlock_irqrestore( &oob_priv->dp_port_lock, flags );

	if( ret ) {
		err("%s: usb_submit_urb failed, ret=%d", __FUNCTION__,
			ret );
	}

	return( ret );

}


/*
*  Digi Write In Band Command
*
*  Write commands on the given port.  Commands are 4
*  bytes each, multiple commands can be sent at once, and
*  no command will be split across USB packets.  If timeout
*  is non-zero, write in band command will return after
*  waiting unsuccessfully for the URB status to clear for
*  timeout ticks.  Returns 0 if successful, or a negative
*  error returned by digi_write.
*/

static int digi_write_inb_command( struct usb_serial_port *port,
	unsigned char *buf, int count, unsigned long timeout )
{

	int ret = 0;
	int len;
	struct digi_port *priv = usb_get_serial_port_data(port);
	unsigned char *data = port->write_urb->transfer_buffer;
	unsigned long flags = 0;


dbg( "digi_write_inb_command: TOP: port=%d, count=%d", priv->dp_port_num,
count );

	if( timeout )
		timeout += jiffies;
	else
		timeout = ULONG_MAX;

	spin_lock_irqsave( &priv->dp_port_lock, flags );

	while( count > 0 && ret == 0 ) {

		while( (port->write_urb->status == -EINPROGRESS
		|| priv->dp_write_urb_in_use) && time_before(jiffies, timeout)) {
			cond_wait_interruptible_timeout_irqrestore(
				&port->write_wait, DIGI_RETRY_TIMEOUT,
				&priv->dp_port_lock, flags );
			if( signal_pending(current) ) {
				return( -EINTR );
			}
			spin_lock_irqsave( &priv->dp_port_lock, flags );
		}

		/* len must be a multiple of 4 and small enough to */
		/* guarantee the write will send buffered data first, */
		/* so commands are in order with data and not split */
		len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len );
		if( len > 4 )
			len &= ~3;

		/* write any buffered data first */
		if( priv->dp_out_buf_len > 0 ) {
			data[0] = DIGI_CMD_SEND_DATA;
			data[1] = priv->dp_out_buf_len;
			memcpy( data+2, priv->dp_out_buf,
				priv->dp_out_buf_len );
			memcpy( data+2+priv->dp_out_buf_len, buf, len );
			port->write_urb->transfer_buffer_length
				= priv->dp_out_buf_len+2+len;
		} else {
			memcpy( data, buf, len );
			port->write_urb->transfer_buffer_length = len;
		}
		port->write_urb->dev = port->serial->dev;

		if( (ret=usb_submit_urb(port->write_urb, GFP_ATOMIC)) == 0 ) {
			priv->dp_write_urb_in_use = 1;
			priv->dp_out_buf_len = 0;
			count -= len;
			buf += len;
		}

	}

	spin_unlock_irqrestore( &priv->dp_port_lock, flags );

	if( ret ) {
		err("%s: usb_submit_urb failed, ret=%d, port=%d", __FUNCTION__,
		ret, priv->dp_port_num );
	}

	return( ret );

}


/*
*  Digi Set Modem Signals
*
*  Sets or clears DTR and RTS on the port, according to the
*  modem_signals argument.  Use TIOCM_DTR and TIOCM_RTS flags
*  for the modem_signals argument.  Returns 0 if successful,
*  -EINTR if interrupted while sleeping, or a non-zero error
*  returned by usb_submit_urb.
*/

static int digi_set_modem_signals( struct usb_serial_port *port,
	unsigned int modem_signals, int interruptible )
{

	int ret;
	struct digi_port *port_priv = usb_get_serial_port_data(port);
	struct usb_serial_port *oob_port = (struct usb_serial_port *)((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
	unsigned char *data = oob_port->write_urb->transfer_buffer;
	unsigned long flags = 0;


dbg( "digi_set_modem_signals: TOP: port=%d, modem_signals=0x%x",
port_priv->dp_port_num, modem_signals );

	spin_lock_irqsave( &oob_priv->dp_port_lock, flags );
	spin_lock( &port_priv->dp_port_lock );

	while( oob_port->write_urb->status == -EINPROGRESS
	|| oob_priv->dp_write_urb_in_use ) {
		spin_unlock( &port_priv->dp_port_lock );
		cond_wait_interruptible_timeout_irqrestore(
			&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
			&oob_priv->dp_port_lock, flags );
		if( interruptible && signal_pending(current) ) {
			return( -EINTR );
		}
		spin_lock_irqsave( &oob_priv->dp_port_lock, flags );
		spin_lock( &port_priv->dp_port_lock );
	}

	data[0] = DIGI_CMD_SET_DTR_SIGNAL;
	data[1] = port_priv->dp_port_num;
	data[2] = (modem_signals&TIOCM_DTR) ?
		DIGI_DTR_ACTIVE : DIGI_DTR_INACTIVE;
	data[3] = 0;

	data[4] = DIGI_CMD_SET_RTS_SIGNAL;
	data[5] = port_priv->dp_port_num;
	data[6] = (modem_signals&TIOCM_RTS) ?
		DIGI_RTS_ACTIVE : DIGI_RTS_INACTIVE;
	data[7] = 0;

	oob_port->write_urb->transfer_buffer_length = 8;
	oob_port->write_urb->dev = port->serial->dev;

	if( (ret=usb_submit_urb(oob_port->write_urb, GFP_ATOMIC)) == 0 ) {
		oob_priv->dp_write_urb_in_use = 1;
		port_priv->dp_modem_signals =
			(port_priv->dp_modem_signals&~(TIOCM_DTR|TIOCM_RTS))
			| (modem_signals&(TIOCM_DTR|TIOCM_RTS));
	}

	spin_unlock( &port_priv->dp_port_lock );
	spin_unlock_irqrestore( &oob_priv->dp_port_lock, flags );

	if( ret ) {
		err("%s: usb_submit_urb failed, ret=%d", __FUNCTION__,
		ret );
	}

	return( ret );

}


/*
*  Digi Transmit Idle
*
*  Digi transmit idle waits, up to timeout ticks, for the transmitter
*  to go idle.  It returns 0 if successful or a negative error.
*
*  There are race conditions here if more than one process is calling
*  digi_transmit_idle on the same port at the same time.  However, this
*  is only called from close, and only one process can be in close on a
*  port at a time, so its ok.
*/

static int digi_transmit_idle( struct usb_serial_port *port,
	unsigned long timeout )
{

	int ret;
	unsigned char buf[2];
	struct digi_port *priv = usb_get_serial_port_data(port);
	unsigned long flags = 0;


	spin_lock_irqsave( &priv->dp_port_lock, flags );
	priv->dp_transmit_idle = 0;
	spin_unlock_irqrestore( &priv->dp_port_lock, flags );

	buf[0] = DIGI_CMD_TRANSMIT_IDLE;
	buf[1] = 0;

	timeout += jiffies;

	if( (ret=digi_write_inb_command( port, buf, 2, timeout-jiffies )) != 0 )
		return( ret );

	spin_lock_irqsave( &priv->dp_port_lock, flags );

	while( time_before(jiffies, timeout) && !priv->dp_transmit_idle ) {
		cond_wait_interruptible_timeout_irqrestore(
			&priv->dp_transmit_idle_wait, DIGI_RETRY_TIMEOUT,
			&priv->dp_port_lock, flags );
		if( signal_pending(current) ) {
			return( -EINTR );
		}
		spin_lock_irqsave( &priv->dp_port_lock, flags );
	}

	priv->dp_transmit_idle = 0;
	spin_unlock_irqrestore( &priv->dp_port_lock, flags );

	return( 0 );

}


static void digi_rx_throttle( struct usb_serial_port *port )
{

	unsigned long flags;
	struct digi_port *priv = usb_get_serial_port_data(port);


dbg( "digi_rx_throttle: TOP: port=%d", priv->dp_port_num );

	/* stop receiving characters by not resubmitting the read urb */
	spin_lock_irqsave( &priv->dp_port_lock, flags );
	priv->dp_throttled = 1;
	priv->dp_throttle_restart = 0;
	priv->dp_in_buf_len = 0;
	spin_unlock_irqrestore( &priv->dp_port_lock, flags );

}


static void digi_rx_unthrottle( struct usb_serial_port *port )
{

	int ret = 0;
	int len;
	unsigned long flags;
	struct digi_port *priv = usb_get_serial_port_data(port);
	struct tty_struct *tty = port->tty;


dbg( "digi_rx_unthrottle: TOP: port=%d", priv->dp_port_num );

	spin_lock_irqsave( &priv->dp_port_lock, flags );

	/* send any buffered chars from throttle time on to tty subsystem */
	len = min(priv->dp_in_buf_len, TTY_FLIPBUF_SIZE - tty->flip.count );
	if( len > 0 ) {
		memcpy( tty->flip.char_buf_ptr, priv->dp_in_buf, len );
		memcpy( tty->flip.flag_buf_ptr, priv->dp_in_flag_buf, len );
		tty->flip.char_buf_ptr += len;
		tty->flip.flag_buf_ptr += len;
		tty->flip.count += len;
		tty_flip_buffer_push( tty );
	}

	/* restart read chain */
	if( priv->dp_throttle_restart ) {
		port->read_urb->dev = port->serial->dev;
		ret = usb_submit_urb( port->read_urb, GFP_ATOMIC );
	}

	/* turn throttle off */
	priv->dp_throttled = 0;
	priv->dp_in_buf_len = 0;
	priv->dp_throttle_restart = 0;

	spin_unlock_irqrestore( &priv->dp_port_lock, flags );

	if( ret ) {
		err("%s: usb_submit_urb failed, ret=%d, port=%d", __FUNCTION__,
			ret, priv->dp_port_num );
	}

}


static void digi_set_termios( struct usb_serial_port *port, 
	struct termios *old_termios )
{

	struct digi_port *priv = usb_get_serial_port_data(port);
	unsigned int iflag = port->tty->termios->c_iflag;
	unsigned int cflag = port->tty->termios->c_cflag;
	unsigned int old_iflag = old_termios->c_iflag;
	unsigned int old_cflag = old_termios->c_cflag;
	unsigned char buf[32];
	unsigned int modem_signals;
	int arg,ret;
	int i = 0;


dbg( "digi_set_termios: TOP: port=%d, iflag=0x%x, old_iflag=0x%x, cflag=0x%x, old_cflag=0x%x", priv->dp_port_num, iflag, old_iflag, cflag, old_cflag );

	/* set baud rate */
	if( (cflag&CBAUD) != (old_cflag&CBAUD) ) {

		arg = -1;

		/* reassert DTR and (maybe) RTS on transition from B0 */
		if( (old_cflag&CBAUD) == B0 ) {
			/* don't set RTS if using hardware flow control */
			/* and throttling input */
			modem_signals = TIOCM_DTR;
			if( !(port->tty->termios->c_cflag & CRTSCTS) ||
			!test_bit(TTY_THROTTLED, &port->tty->flags) ) {
				modem_signals |= TIOCM_RTS;
			}
			digi_set_modem_signals( port, modem_signals, 1 );
		}

		switch( (cflag&CBAUD) ) {
			/* drop DTR and RTS on transition to B0 */
		case B0: digi_set_modem_signals( port, 0, 1 ); break;
		case B50: arg = DIGI_BAUD_50; break;
		case B75: arg = DIGI_BAUD_75; break;
		case B110: arg = DIGI_BAUD_110; break;
		case B150: arg = DIGI_BAUD_150; break;
		case B200: arg = DIGI_BAUD_200; break;
		case B300: arg = DIGI_BAUD_300; break;
		case B600: arg = DIGI_BAUD_600; break;
		case B1200: arg = DIGI_BAUD_1200; break;
		case B1800: arg = DIGI_BAUD_1800; break;
		case B2400: arg = DIGI_BAUD_2400; break;
		case B4800: arg = DIGI_BAUD_4800; break;
		case B9600: arg = DIGI_BAUD_9600; break;