ir-usb.c

linux 内核源代码

			return -ENOMEM;
		}
		kfree (port->write_urb->transfer_buffer);
		port->write_urb->transfer_buffer = buffer;
		port->write_urb->transfer_buffer_length = buffer_size;
		port->bulk_out_size = buffer_size;
	}

	/* Start reading from the device */
	usb_fill_bulk_urb (
		port->read_urb,
		port->serial->dev, 
		usb_rcvbulkpipe(port->serial->dev, port->bulk_in_endpointAddress),
		port->read_urb->transfer_buffer,
		port->read_urb->transfer_buffer_length,
		ir_read_bulk_callback,
		port);
	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
	if (result)
		dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);

	return result;
}

static void ir_close (struct usb_serial_port *port, struct file * filp)
{
	dbg("%s - port %d", __FUNCTION__, port->number);
			 
	/* shutdown our bulk read */
	usb_kill_urb(port->read_urb);
}

static int ir_write (struct usb_serial_port *port, const unsigned char *buf, int count)
{
	unsigned char *transfer_buffer;
	int result;
	int transfer_size;

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

	if (!port->tty) {
		dev_err (&port->dev, "%s - no tty???\n", __FUNCTION__);
		return 0;
	}

	if (count == 0)
		return 0;

	spin_lock_bh(&port->lock);
	if (port->write_urb_busy) {
		spin_unlock_bh(&port->lock);
		dbg("%s - already writing", __FUNCTION__);
		return 0;
	}
	port->write_urb_busy = 1;
	spin_unlock_bh(&port->lock);

	transfer_buffer = port->write_urb->transfer_buffer;
	transfer_size = min(count, port->bulk_out_size - 1);

	/*
	 * The first byte of the packet we send to the device contains an
	 * inband header which indicates an additional number of BOFs and
	 * a baud rate change.
	 *
	 * See section 5.4.2.2 of the USB IrDA spec.
	 */
	*transfer_buffer = ir_xbof | ir_baud;
	++transfer_buffer;

	memcpy (transfer_buffer, buf, transfer_size);

	usb_fill_bulk_urb (
		port->write_urb,
		port->serial->dev,
		usb_sndbulkpipe(port->serial->dev,
			port->bulk_out_endpointAddress),
		port->write_urb->transfer_buffer,
		transfer_size + 1,
		ir_write_bulk_callback,
		port);

	port->write_urb->transfer_flags = URB_ZERO_PACKET;

	result = usb_submit_urb (port->write_urb, GFP_ATOMIC);
	if (result) {
		port->write_urb_busy = 0;
		dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
	} else
		result = transfer_size;

	return result;
}

static void ir_write_bulk_callback (struct urb *urb)
{
	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	int status = urb->status;

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

	port->write_urb_busy = 0;
	if (status) {
		dbg("%s - nonzero write bulk status received: %d",
		    __FUNCTION__, status);
		return;
	}

	usb_serial_debug_data (
		debug,
		&port->dev,
		__FUNCTION__,
		urb->actual_length,
		urb->transfer_buffer);

	usb_serial_port_softint(port);
}

static void ir_read_bulk_callback (struct urb *urb)
{
	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct tty_struct *tty;
	unsigned char *data = urb->transfer_buffer;
	int result;
	int status = urb->status;

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

	if (!port->open_count) {
		dbg("%s - port closed.", __FUNCTION__);
		return;
	}

	switch (status) {
		case 0: /* Successful */

			/*
			 * The first byte of the packet we get from the device
			 * contains a busy indicator and baud rate change.
			 * See section 5.4.1.2 of the USB IrDA spec.
			 */
			if ((*data & 0x0f) > 0)
				ir_baud = *data & 0x0f;

			usb_serial_debug_data (
				debug,
				&port->dev,
				__FUNCTION__,
				urb->actual_length,
				data);

			tty = port->tty;

			if (tty_buffer_request_room(tty, urb->actual_length - 1)) {
				tty_insert_flip_string(tty, data+1, urb->actual_length - 1);
				tty_flip_buffer_push(tty);
			}

			/*
			 * No break here.
			 * We want to resubmit the urb so we can read
			 * again.
			 */

		case -EPROTO: /* taking inspiration from pl2303.c */

			/* Continue trying to always read */
			usb_fill_bulk_urb (
				port->read_urb,
				port->serial->dev, 
				usb_rcvbulkpipe(port->serial->dev,
					port->bulk_in_endpointAddress),
				port->read_urb->transfer_buffer,
				port->read_urb->transfer_buffer_length,
				ir_read_bulk_callback,
				port);

			result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
			if (result)
				dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n",
					__FUNCTION__, result);

			break ;

		default:
			dbg("%s - nonzero read bulk status received: %d",
				__FUNCTION__, 
				status);
			break ;

	}

	return;
}

static void ir_set_termios (struct usb_serial_port *port, struct ktermios *old_termios)
{
	unsigned char *transfer_buffer;
	int result;
	speed_t baud;
	int ir_baud;

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

	baud = tty_get_baud_rate(port->tty);

	/*
	 * FIXME, we should compare the baud request against the
	 * capability stated in the IR header that we got in the
	 * startup function.
	 */

	switch (baud) {
		case 2400:	ir_baud = SPEED_2400; break;
		case 9600:	ir_baud = SPEED_9600; break;
		case 19200:	ir_baud = SPEED_19200; break;
		case 38400:	ir_baud = SPEED_38400; break;
		case 57600:	ir_baud = SPEED_57600; break;
		case 115200:	ir_baud = SPEED_115200; break;
		case 576000:	ir_baud = SPEED_576000; break;
		case 1152000:	ir_baud = SPEED_1152000; break;
		case 4000000:	ir_baud = SPEED_4000000; break;
			break;
		default:
			ir_baud = SPEED_9600;
			baud = 9600;
	}

	if (xbof == -1)
		ir_xbof = ir_xbof_change(ir_add_bof);
	else
		ir_xbof = ir_xbof_change(xbof) ;

	/* FIXME need to check to see if our write urb is busy right
	 * now, or use a urb pool.
	 *
	 * send the baud change out on an "empty" data packet
	 */
	transfer_buffer = port->write_urb->transfer_buffer;
	*transfer_buffer = ir_xbof | ir_baud;

	usb_fill_bulk_urb (
		port->write_urb,
		port->serial->dev,
		usb_sndbulkpipe(port->serial->dev, port->bulk_out_endpointAddress),
		port->write_urb->transfer_buffer,
		1,
		ir_write_bulk_callback,
		port);

	port->write_urb->transfer_flags = URB_ZERO_PACKET;

	result = usb_submit_urb (port->write_urb, GFP_KERNEL);
	if (result)
		dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);

	/* Only speed changes are supported */
	tty_termios_copy_hw(port->tty->termios, old_termios);
	tty_encode_baud_rate(port->tty, baud, baud);
}


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


static void __exit ir_exit (void)
{
	usb_deregister (&ir_driver);
	usb_serial_deregister (&ir_device);
}


module_init(ir_init);
module_exit(ir_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");
module_param(xbof, int, 0);
MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
module_param(buffer_size, int, 0);
MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");