mct_u232.c

linux-2.6.15.6

{
	struct usb_serial *serial = port->serial;
	struct mct_u232_private *priv = usb_get_serial_port_data(port);
	int retval = 0;
	unsigned int control_state;
	unsigned long flags;
	unsigned char last_lcr;
	unsigned char last_msr;

	dbg("%s port %d", __FUNCTION__, port->number);

	/* Compensate for a hardware bug: although the Sitecom U232-P25
	 * device reports a maximum output packet size of 32 bytes,
	 * it seems to be able to accept only 16 bytes (and that's what
	 * SniffUSB says too...)
	 */
	if (le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_SITECOM_PID)
		port->bulk_out_size = 16;

	/* Do a defined restart: the normal serial device seems to 
	 * always turn on DTR and RTS here, so do the same. I'm not
	 * sure if this is really necessary. But it should not harm
	 * either.
	 */
	spin_lock_irqsave(&priv->lock, flags);
	if (port->tty->termios->c_cflag & CBAUD)
		priv->control_state = TIOCM_DTR | TIOCM_RTS;
	else
		priv->control_state = 0;
	
	priv->last_lcr = (MCT_U232_DATA_BITS_8 | 
			  MCT_U232_PARITY_NONE |
			  MCT_U232_STOP_BITS_1);
	control_state = priv->control_state;
	last_lcr = priv->last_lcr;
	spin_unlock_irqrestore(&priv->lock, flags);
	mct_u232_set_modem_ctrl(serial, control_state);
	mct_u232_set_line_ctrl(serial, last_lcr);

	/* Read modem status and update control state */
	mct_u232_get_modem_stat(serial, &last_msr);
	spin_lock_irqsave(&priv->lock, flags);
	priv->last_msr = last_msr;
	mct_u232_msr_to_state(&priv->control_state, priv->last_msr);
	spin_unlock_irqrestore(&priv->lock, flags);

	port->read_urb->dev = port->serial->dev;
	retval = usb_submit_urb(port->read_urb, GFP_KERNEL);
	if (retval) {
		err("usb_submit_urb(read bulk) failed pipe 0x%x err %d",
		    port->read_urb->pipe, retval);
		goto exit;
	}

	port->interrupt_in_urb->dev = port->serial->dev;
	retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
	if (retval)
		err(" usb_submit_urb(read int) failed pipe 0x%x err %d",
		    port->interrupt_in_urb->pipe, retval);

exit:
	return 0;
} /* mct_u232_open */


static void mct_u232_close (struct usb_serial_port *port, struct file *filp)
{
	dbg("%s port %d", __FUNCTION__, port->number);

	if (port->serial->dev) {
		/* shutdown our urbs */
		usb_kill_urb(port->write_urb);
		usb_kill_urb(port->read_urb);
		usb_kill_urb(port->interrupt_in_urb);
	}
} /* mct_u232_close */


static void mct_u232_read_int_callback (struct urb *urb, struct pt_regs *regs)
{
	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct mct_u232_private *priv = usb_get_serial_port_data(port);
	struct usb_serial *serial = port->serial;
	struct tty_struct *tty;
	unsigned char *data = urb->transfer_buffer;
	int status;
	unsigned long flags;

	switch (urb->status) {
	case 0:
		/* success */
		break;
	case -ECONNRESET:
	case -ENOENT:
	case -ESHUTDOWN:
		/* this urb is terminated, clean up */
		dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
		return;
	default:
		dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
		goto exit;
	}

	if (!serial) {
		dbg("%s - bad serial pointer, exiting", __FUNCTION__);
		return;
	}

        dbg("%s - port %d", __FUNCTION__, port->number);
	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);

	/*
	 * Work-a-round: handle the 'usual' bulk-in pipe here
	 */
	if (urb->transfer_buffer_length > 2) {
		int i;
		tty = port->tty;
		if (urb->actual_length) {
			for (i = 0; i < urb->actual_length ; ++i) {
				tty_insert_flip_char(tty, data[i], 0);
			}
			tty_flip_buffer_push(tty);
		}
		goto exit;
	}
	
	/*
	 * The interrupt-in pipe signals exceptional conditions (modem line
	 * signal changes and errors). data[0] holds MSR, data[1] holds LSR.
	 */
	spin_lock_irqsave(&priv->lock, flags);
	priv->last_msr = data[MCT_U232_MSR_INDEX];
	
	/* Record Control Line states */
	mct_u232_msr_to_state(&priv->control_state, priv->last_msr);

#if 0
	/* Not yet handled. See belin_sa.c for further information */
	/* Now to report any errors */
	priv->last_lsr = data[MCT_U232_LSR_INDEX];
	/*
	 * fill in the flip buffer here, but I do not know the relation
	 * to the current/next receive buffer or characters.  I need
	 * to look in to this before committing any code.
	 */
	if (priv->last_lsr & MCT_U232_LSR_ERR) {
		tty = port->tty;
		/* Overrun Error */
		if (priv->last_lsr & MCT_U232_LSR_OE) {
		}
		/* Parity Error */
		if (priv->last_lsr & MCT_U232_LSR_PE) {
		}
		/* Framing Error */
		if (priv->last_lsr & MCT_U232_LSR_FE) {
		}
		/* Break Indicator */
		if (priv->last_lsr & MCT_U232_LSR_BI) {
		}
	}
#endif
	spin_unlock_irqrestore(&priv->lock, flags);
exit:
	status = usb_submit_urb (urb, GFP_ATOMIC);
	if (status)
		err ("%s - usb_submit_urb failed with result %d",
		     __FUNCTION__, status);
} /* mct_u232_read_int_callback */

static void mct_u232_set_termios (struct usb_serial_port *port,
				  struct termios *old_termios)
{
	struct usb_serial *serial = port->serial;
	struct mct_u232_private *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_cflag = old_termios->c_cflag;
	unsigned long flags;
	unsigned int control_state, new_state;
	unsigned char last_lcr;

	/* get a local copy of the current port settings */
	spin_lock_irqsave(&priv->lock, flags);
	control_state = priv->control_state;
	spin_unlock_irqrestore(&priv->lock, flags);
	last_lcr = 0;

	/*
	 * Update baud rate.
	 * Do not attempt to cache old rates and skip settings,
	 * disconnects screw such tricks up completely.
	 * Premature optimization is the root of all evil.
	 */

        /* reassert DTR and (maybe) RTS on transition from B0 */
	if ((old_cflag & CBAUD) == B0) {
		dbg("%s: baud was B0", __FUNCTION__);
		control_state |= TIOCM_DTR;
		/* don't set RTS if using hardware flow control */
		if (!(old_cflag & CRTSCTS)) {
			control_state |= TIOCM_RTS;
		}
		mct_u232_set_modem_ctrl(serial, control_state);
	}

	mct_u232_set_baud_rate(serial, cflag & CBAUD);

	if ((cflag & CBAUD) == B0 ) {
		dbg("%s: baud is B0", __FUNCTION__);
		/* Drop RTS and DTR */
		control_state &= ~(TIOCM_DTR | TIOCM_RTS);
       		mct_u232_set_modem_ctrl(serial, control_state);
	}

	/*
	 * Update line control register (LCR)
	 */

	/* set the parity */
	if (cflag & PARENB)
		last_lcr |= (cflag & PARODD) ?
			MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
	else
		last_lcr |= MCT_U232_PARITY_NONE;

	/* set the number of data bits */
	switch (cflag & CSIZE) {
	case CS5:
		last_lcr |= MCT_U232_DATA_BITS_5; break;
	case CS6:
		last_lcr |= MCT_U232_DATA_BITS_6; break;
	case CS7:
		last_lcr |= MCT_U232_DATA_BITS_7; break;
	case CS8:
		last_lcr |= MCT_U232_DATA_BITS_8; break;
	default:
		err("CSIZE was not CS5-CS8, using default of 8");
		last_lcr |= MCT_U232_DATA_BITS_8;
		break;
	}

	/* set the number of stop bits */
	last_lcr |= (cflag & CSTOPB) ?
		MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;

	mct_u232_set_line_ctrl(serial, last_lcr);

	/*
	 * Set flow control: well, I do not really now how to handle DTR/RTS.
	 * Just do what we have seen with SniffUSB on Win98.
	 */
	/* Drop DTR/RTS if no flow control otherwise assert */
	new_state = control_state;
	if ((iflag & IXOFF) || (iflag & IXON) || (cflag & CRTSCTS))
		new_state |= TIOCM_DTR | TIOCM_RTS;
	else
		new_state &= ~(TIOCM_DTR | TIOCM_RTS);
	if (new_state != control_state) {
		mct_u232_set_modem_ctrl(serial, new_state);
		control_state = new_state;
	}

	/* save off the modified port settings */
	spin_lock_irqsave(&priv->lock, flags);
	priv->control_state = control_state;
	priv->last_lcr = last_lcr;
	spin_unlock_irqrestore(&priv->lock, flags);
} /* mct_u232_set_termios */

static void mct_u232_break_ctl( struct usb_serial_port *port, int break_state )
{
	struct usb_serial *serial = port->serial;
	struct mct_u232_private *priv = usb_get_serial_port_data(port);
	unsigned char lcr;
	unsigned long flags;

	dbg("%sstate=%d", __FUNCTION__, break_state);

	spin_lock_irqsave(&priv->lock, flags);
	lcr = priv->last_lcr;
	spin_unlock_irqrestore(&priv->lock, flags);

	if (break_state)
		lcr |= MCT_U232_SET_BREAK;

	mct_u232_set_line_ctrl(serial, lcr);
} /* mct_u232_break_ctl */


static int mct_u232_tiocmget (struct usb_serial_port *port, struct file *file)
{
	struct mct_u232_private *priv = usb_get_serial_port_data(port);
	unsigned int control_state;
	unsigned long flags;
	
	dbg("%s", __FUNCTION__);

	spin_lock_irqsave(&priv->lock, flags);
	control_state = priv->control_state;
	spin_unlock_irqrestore(&priv->lock, flags);

	return control_state;
}

static int mct_u232_tiocmset (struct usb_serial_port *port, struct file *file,
			      unsigned int set, unsigned int clear)
{
	struct usb_serial *serial = port->serial;
	struct mct_u232_private *priv = usb_get_serial_port_data(port);
	unsigned int control_state;
	unsigned long flags;
	
	dbg("%s", __FUNCTION__);

	spin_lock_irqsave(&priv->lock, flags);
	control_state = priv->control_state;

	if (set & TIOCM_RTS)
		control_state |= TIOCM_RTS;
	if (set & TIOCM_DTR)
		control_state |= TIOCM_DTR;
	if (clear & TIOCM_RTS)
		control_state &= ~TIOCM_RTS;
	if (clear & TIOCM_DTR)
		control_state &= ~TIOCM_DTR;

	priv->control_state = control_state;
	spin_unlock_irqrestore(&priv->lock, flags);
	return mct_u232_set_modem_ctrl(serial, control_state);
}

static int mct_u232_ioctl (struct usb_serial_port *port, struct file * file,
			   unsigned int cmd, unsigned long arg)
{
	dbg("%scmd=0x%x", __FUNCTION__, cmd);

	/* Based on code from acm.c and others */
	switch (cmd) {
	case TIOCMIWAIT:
		/* wait for any of the 4 modem inputs (DCD,RI,DSR,CTS)*/
		/* TODO */
		return( 0 );

	case TIOCGICOUNT:
		/* return count of modemline transitions */
		/* TODO */
		return 0;

	default:
		dbg("%s: arg not supported - 0x%04x", __FUNCTION__,cmd);
		return(-ENOIOCTLCMD);
		break;
	}
	return 0;
} /* mct_u232_ioctl */


static int __init mct_u232_init (void)
{
	int retval;
	retval = usb_serial_register(&mct_u232_device);
	if (retval)
		goto failed_usb_serial_register;
	retval = usb_register(&mct_u232_driver);
	if (retval)
		goto failed_usb_register;
	info(DRIVER_DESC " " DRIVER_VERSION);
	return 0;
failed_usb_register:
	usb_serial_deregister(&mct_u232_device);
failed_usb_serial_register:
	return retval;
}


static void __exit mct_u232_exit (void)
{
	usb_deregister (&mct_u232_driver);
	usb_serial_deregister (&mct_u232_device);
}


module_init (mct_u232_init);
module_exit(mct_u232_exit);

MODULE_AUTHOR( DRIVER_AUTHOR );
MODULE_DESCRIPTION( DRIVER_DESC );
MODULE_LICENSE("GPL");

module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");