digi_acceleport.c

linux-2.6.15.6

	/* do cleanup only after final close on this port */
	spin_lock_irqsave( &priv->dp_port_lock, flags );
	priv->dp_in_close = 1;
	spin_unlock_irqrestore( &priv->dp_port_lock, flags );

	/* tell line discipline to process only XON/XOFF */
	tty->closing = 1;

	/* wait for output to drain */
	if( (filp->f_flags&(O_NDELAY|O_NONBLOCK)) == 0 ) {
		tty_wait_until_sent( tty, DIGI_CLOSE_TIMEOUT );
	}

	/* flush driver and line discipline buffers */
	if( tty->driver->flush_buffer )
		tty->driver->flush_buffer( tty );
	tty_ldisc_flush(tty);

	if (port->serial->dev) {
		/* wait for transmit idle */
		if( (filp->f_flags&(O_NDELAY|O_NONBLOCK)) == 0 ) {
			digi_transmit_idle( port, DIGI_CLOSE_TIMEOUT );
		}

		/* drop DTR and RTS */
		digi_set_modem_signals( port, 0, 0 );

		/* disable input flow control */
		buf[0] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
		buf[1] = priv->dp_port_num;
		buf[2] = DIGI_DISABLE;
		buf[3] = 0;

		/* disable output flow control */
		buf[4] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
		buf[5] = priv->dp_port_num;
		buf[6] = DIGI_DISABLE;
		buf[7] = 0;

		/* disable reading modem signals automatically */
		buf[8] = DIGI_CMD_READ_INPUT_SIGNALS;
		buf[9] = priv->dp_port_num;
		buf[10] = DIGI_DISABLE;
		buf[11] = 0;

		/* disable receive */
		buf[12] = DIGI_CMD_RECEIVE_ENABLE;
		buf[13] = priv->dp_port_num;
		buf[14] = DIGI_DISABLE;
		buf[15] = 0;

		/* flush fifos */
		buf[16] = DIGI_CMD_IFLUSH_FIFO;
		buf[17] = priv->dp_port_num;
		buf[18] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
		buf[19] = 0;

		if( (ret=digi_write_oob_command( port, buf, 20, 0 )) != 0 )
			dbg( "digi_close: write oob failed, ret=%d", ret );

		/* wait for final commands on oob port to complete */
		prepare_to_wait(&priv->dp_flush_wait, &wait, TASK_INTERRUPTIBLE);
		schedule_timeout(DIGI_CLOSE_TIMEOUT);
		finish_wait(&priv->dp_flush_wait, &wait);

		/* shutdown any outstanding bulk writes */
		usb_kill_urb(port->write_urb);
	}

	tty->closing = 0;

exit:
	spin_lock_irqsave( &priv->dp_port_lock, flags );
	priv->dp_write_urb_in_use = 0;
	priv->dp_in_close = 0;
	wake_up_interruptible( &priv->dp_close_wait );
	spin_unlock_irqrestore( &priv->dp_port_lock, flags );

dbg( "digi_close: done" );
}


/*
*  Digi Startup Device
*
*  Starts reads on all ports.  Must be called AFTER startup, with
*  urbs initialized.  Returns 0 if successful, non-zero error otherwise.
*/

static int digi_startup_device( struct usb_serial *serial )
{

	int i,ret = 0;
	struct digi_serial *serial_priv = usb_get_serial_data(serial);
	struct usb_serial_port *port;


	/* be sure this happens exactly once */
	spin_lock( &serial_priv->ds_serial_lock );
	if( serial_priv->ds_device_started ) {
		spin_unlock( &serial_priv->ds_serial_lock );
		return( 0 );
	}
	serial_priv->ds_device_started = 1;
	spin_unlock( &serial_priv->ds_serial_lock );

	/* start reading from each bulk in endpoint for the device */
	/* set USB_DISABLE_SPD flag for write bulk urbs */
	for( i=0; i<serial->type->num_ports+1; i++ ) {

		port = serial->port[i];

		port->write_urb->dev = port->serial->dev;

		if( (ret=usb_submit_urb(port->read_urb, GFP_KERNEL)) != 0 ) {
			err("%s: usb_submit_urb failed, ret=%d, port=%d", __FUNCTION__,
			ret, i );
			break;
		}

	}

	return( ret );

}


static int digi_startup( struct usb_serial *serial )
{

	int i;
	struct digi_port *priv;
	struct digi_serial *serial_priv;


dbg( "digi_startup: TOP" );

	/* allocate the private data structures for all ports */
	/* number of regular ports + 1 for the out-of-band port */
	for( i=0; i<serial->type->num_ports+1; i++ ) {

		/* allocate port private structure */
		priv = (struct digi_port *)kmalloc( sizeof(struct digi_port),
			GFP_KERNEL );
		if( priv == (struct digi_port *)0 ) {
			while( --i >= 0 )
				kfree( usb_get_serial_port_data(serial->port[i]) );
			return( 1 );			/* error */
		}

		/* initialize port private structure */
		spin_lock_init( &priv->dp_port_lock );
		priv->dp_port_num = i;
		priv->dp_out_buf_len = 0;
		priv->dp_in_buf_len = 0;
		priv->dp_write_urb_in_use = 0;
		priv->dp_modem_signals = 0;
		init_waitqueue_head( &priv->dp_modem_change_wait );
		priv->dp_transmit_idle = 0;
		init_waitqueue_head( &priv->dp_transmit_idle_wait );
		priv->dp_throttled = 0;
		priv->dp_throttle_restart = 0;
		init_waitqueue_head( &priv->dp_flush_wait );
		priv->dp_in_close = 0;
		init_waitqueue_head( &priv->dp_close_wait );
		INIT_WORK(&priv->dp_wakeup_work,
				digi_wakeup_write_lock, serial->port[i]);

		/* initialize write wait queue for this port */
		init_waitqueue_head( &serial->port[i]->write_wait );

		usb_set_serial_port_data(serial->port[i], priv);
	}

	/* allocate serial private structure */
	serial_priv = (struct digi_serial *)kmalloc( sizeof(struct digi_serial),
		GFP_KERNEL );
	if( serial_priv == (struct digi_serial *)0 ) {
		for( i=0; i<serial->type->num_ports+1; i++ )
			kfree( usb_get_serial_port_data(serial->port[i]) );
		return( 1 );			/* error */
	}

	/* initialize serial private structure */
	spin_lock_init( &serial_priv->ds_serial_lock );
	serial_priv->ds_oob_port_num = serial->type->num_ports;
	serial_priv->ds_oob_port = serial->port[serial_priv->ds_oob_port_num];
	serial_priv->ds_device_started = 0;
	usb_set_serial_data(serial, serial_priv);

	return( 0 );

}


static void digi_shutdown( struct usb_serial *serial )
{

	int i;


dbg( "digi_shutdown: TOP, in_interrupt()=%ld", in_interrupt() );

	/* stop reads and writes on all ports */
	for( i=0; i<serial->type->num_ports+1; i++ ) {
		usb_kill_urb(serial->port[i]->read_urb);
		usb_kill_urb(serial->port[i]->write_urb);
	}

	/* free the private data structures for all ports */
	/* number of regular ports + 1 for the out-of-band port */
	for( i=0; i<serial->type->num_ports+1; i++ )
		kfree( usb_get_serial_port_data(serial->port[i]) );
	kfree( usb_get_serial_data(serial) );
}


static void digi_read_bulk_callback( struct urb *urb, struct pt_regs *regs )
{

	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct digi_port *priv;
	struct digi_serial *serial_priv;
	int ret;


dbg( "digi_read_bulk_callback: TOP" );

	/* port sanity check, do not resubmit if port is not valid */
	if( port == NULL || (priv=usb_get_serial_port_data(port)) == NULL ) {
		err("%s: port or port->private is NULL, status=%d", __FUNCTION__,
			urb->status );
		return;
	}
	if( port->serial == NULL
	|| (serial_priv=usb_get_serial_data(port->serial)) == NULL ) {
		err("%s: serial is bad or serial->private is NULL, status=%d", __FUNCTION__, urb->status );
		return;
	}

	/* do not resubmit urb if it has any status error */
	if( urb->status ) {
		err("%s: nonzero read bulk status: status=%d, port=%d", __FUNCTION__, urb->status, priv->dp_port_num );
		return;
	}

	/* handle oob or inb callback, do not resubmit if error */
	if( priv->dp_port_num == serial_priv->ds_oob_port_num ) {
		if( digi_read_oob_callback( urb ) != 0 )
			return;
	} else {
		if( digi_read_inb_callback( urb ) != 0 )
			return;
	}

	/* continue read */
	urb->dev = port->serial->dev;
	if( (ret=usb_submit_urb(urb, GFP_ATOMIC)) != 0 ) {
		err("%s: failed resubmitting urb, ret=%d, port=%d", __FUNCTION__,
			ret, priv->dp_port_num );
	}

}


/* 
*  Digi Read INB Callback
*
*  Digi Read INB Callback handles reads on the in band ports, sending
*  the data on to the tty subsystem.  When called we know port and
*  port->private are not NULL and port->serial has been validated.
*  It returns 0 if successful, 1 if successful but the port is
*  throttled, and -1 if the sanity checks failed.
*/

static int digi_read_inb_callback( struct urb *urb )
{

	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct tty_struct *tty = port->tty;
	struct digi_port *priv = usb_get_serial_port_data(port);
	int opcode = ((unsigned char *)urb->transfer_buffer)[0];
	int len = ((unsigned char *)urb->transfer_buffer)[1];
	int status = ((unsigned char *)urb->transfer_buffer)[2];
	unsigned char *data = ((unsigned char *)urb->transfer_buffer)+3;
	int flag,throttled;

	/* do not process callbacks on closed ports */
	/* but do continue the read chain */
	if( port->open_count == 0 )
		return( 0 );

	/* short/multiple packet check */
	if( urb->actual_length != len + 2 ) {
     		err("%s: INCOMPLETE OR MULTIPLE PACKET, urb->status=%d, port=%d, opcode=%d, len=%d, actual_length=%d, status=%d", __FUNCTION__, urb->status, priv->dp_port_num, opcode, len, urb->actual_length, status );
		return( -1 );
	}

	spin_lock( &priv->dp_port_lock );

	/* check for throttle; if set, do not resubmit read urb */
	/* indicate the read chain needs to be restarted on unthrottle */
	throttled = priv->dp_throttled;
	if( throttled )
		priv->dp_throttle_restart = 1;

	/* receive data */
	if( opcode == DIGI_CMD_RECEIVE_DATA ) {

		/* get flag from status */
		flag = 0;

		/* overrun is special, not associated with a char */
		if( status & DIGI_OVERRUN_ERROR ) {
			tty_insert_flip_char( tty, 0, TTY_OVERRUN );
		}

		/* break takes precedence over parity, */
		/* which takes precedence over framing errors */
		if( status & DIGI_BREAK_ERROR ) {
			flag = TTY_BREAK;
		} else if( status & DIGI_PARITY_ERROR ) {
			flag = TTY_PARITY;
		} else if( status & DIGI_FRAMING_ERROR ) {
			flag = TTY_FRAME;
		}

		/* data length is len-1 (one byte of len is status) */
		--len;

		if( throttled ) {

			len = min( len,
				DIGI_IN_BUF_SIZE - priv->dp_in_buf_len );

			if( len > 0 ) {
				memcpy( priv->dp_in_buf + priv->dp_in_buf_len,
					data, len );
				memset( priv->dp_in_flag_buf
					+ priv->dp_in_buf_len, flag, len );
				priv->dp_in_buf_len += len;
			}

		} else {

			len = min( len, TTY_FLIPBUF_SIZE - tty->flip.count );

			if( len > 0 ) {
				memcpy( tty->flip.char_buf_ptr, data, len );
				memset( tty->flip.flag_buf_ptr, flag, len );
				tty->flip.char_buf_ptr += len;
				tty->flip.flag_buf_ptr += len;
				tty->flip.count += len;
				tty_flip_buffer_push( tty );
			}

		}

	}

	spin_unlock( &priv->dp_port_lock );

	if( opcode == DIGI_CMD_RECEIVE_DISABLE ) {
		dbg("%s: got RECEIVE_DISABLE", __FUNCTION__ );
	} else if( opcode != DIGI_CMD_RECEIVE_DATA ) {
		dbg("%s: unknown opcode: %d", __FUNCTION__, opcode );
	}

	return( throttled ? 1 : 0 );

}


/* 
*  Digi Read OOB Callback
*
*  Digi Read OOB Callback handles reads on the out of band port.
*  When called we know port and port->private are not NULL and
*  the port->serial is valid.  It returns 0 if successful, and
*  -1 if the sanity checks failed.
*/

static int digi_read_oob_callback( struct urb *urb )
{

	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct usb_serial *serial = port->serial;
	struct digi_port *priv = usb_get_serial_port_data(port);
	int opcode, line, status, val;
	int i;


dbg( "digi_read_oob_callback: port=%d, len=%d", priv->dp_port_num,
urb->actual_length );

	/* handle each oob command */
	for( i=0; i<urb->actual_length-3; ) {

		opcode = ((unsigned char *)urb->transfer_buffer)[i++];
		line = ((unsigned char *)urb->transfer_buffer)[i++];
		status = ((unsigned char *)urb->transfer_buffer)[i++];
		val = ((unsigned char *)urb->transfer_buffer)[i++];

dbg( "digi_read_oob_callback: opcode=%d, line=%d, status=%d, val=%d",
opcode, line, status, val );

		if( status != 0 || line >= serial->type->num_ports )
			continue;

		port = serial->port[line];

		if ((priv=usb_get_serial_port_data(port)) == NULL )
			return -1;

		if( opcode == DIGI_CMD_READ_INPUT_SIGNALS ) {

			spin_lock( &priv->dp_port_lock );

			/* convert from digi flags to termiox flags */
			if( val & DIGI_READ_INPUT_SIGNALS_CTS ) {
				priv->dp_modem_signals |= TIOCM_CTS;
				/* port must be open to use tty struct */
				if( port->open_count
				&& port->tty->termios->c_cflag & CRTSCTS ) {
					port->tty->hw_stopped = 0;
					digi_wakeup_write( port );
				}
			} else {
				priv->dp_modem_signals &= ~TIOCM_CTS;
				/* port must be open to use tty struct */
				if( port->open_count
				&& port->tty->termios->c_cflag & CRTSCTS ) {
					port->tty->hw_stopped = 1;
				}
			}
			if( val & DIGI_READ_INPUT_SIGNALS_DSR )
				priv->dp_modem_signals |= TIOCM_DSR;
			else
				priv->dp_modem_signals &= ~TIOCM_DSR;
			if( val & DIGI_READ_INPUT_SIGNALS_RI )
				priv->dp_modem_signals |= TIOCM_RI;
			else
				priv->dp_modem_signals &= ~TIOCM_RI;
			if( val & DIGI_READ_INPUT_SIGNALS_DCD )
				priv->dp_modem_signals |= TIOCM_CD;
			else
				priv->dp_modem_signals &= ~TIOCM_CD;

			wake_up_interruptible( &priv->dp_modem_change_wait );
			spin_unlock( &priv->dp_port_lock );

		} else if( opcode == DIGI_CMD_TRANSMIT_IDLE ) {

			spin_lock( &priv->dp_port_lock );
			priv->dp_transmit_idle = 1;
			wake_up_interruptible( &priv->dp_transmit_idle_wait );
			spin_unlock( &priv->dp_port_lock );

		} else if( opcode == DIGI_CMD_IFLUSH_FIFO ) {

			wake_up_interruptible( &priv->dp_flush_wait );

		}

	}

	return( 0 );

}


static int __init digi_init (void)
{
	int retval;
	retval = usb_serial_register(&digi_acceleport_2_device);
	if (retval)
		goto failed_acceleport_2_device;
	retval = usb_serial_register(&digi_acceleport_4_device);
	if (retval) 
		goto failed_acceleport_4_device;
	retval = usb_register(&digi_driver);
	if (retval)
		goto failed_usb_register;
	info(DRIVER_VERSION ":" DRIVER_DESC);
	return 0;
failed_usb_register:
	usb_serial_deregister(&digi_acceleport_4_device);
failed_acceleport_4_device:
	usb_serial_deregister(&digi_acceleport_2_device);
failed_acceleport_2_device:
	return retval;
}


static void __exit digi_exit (void)
{
	usb_deregister (&digi_driver);
	usb_serial_deregister (&digi_acceleport_2_device);
	usb_serial_deregister (&digi_acceleport_4_device);
}


module_init(digi_init);
module_exit(digi_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");