ipaq.c

linux-2.6.15.6

		      port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
		      ipaq_read_bulk_callback, port);
	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
	if (result) {
		err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
		goto error;
	}

	/*
	 * Send out control message observed in win98 sniffs. Not sure what
	 * it does, but from empirical observations, it seems that the device
	 * will start the chat sequence once one of these messages gets
	 * through. Since this has a reasonably high failure rate, we retry
	 * several times.
	 */

	while (retries--) {
		result = usb_control_msg(serial->dev,
				usb_sndctrlpipe(serial->dev, 0), 0x22, 0x21,
				0x1, 0, NULL, 0, 100);
		if (result == 0) {
			return 0;
		}
	}
	err("%s - failed doing control urb, error %d", __FUNCTION__, result);
	goto error;

enomem:
	result = -ENOMEM;
	err("%s - Out of memory", __FUNCTION__);
error:
	ipaq_destroy_lists(port);
	kfree(priv);
	return result;
}


static void ipaq_close(struct usb_serial_port *port, struct file *filp)
{
	struct ipaq_private	*priv = usb_get_serial_port_data(port);

	dbg("%s - port %d", __FUNCTION__, port->number);
			 
	/*
	 * shut down bulk read and write
	 */
	usb_kill_urb(port->write_urb);
	usb_kill_urb(port->read_urb);
	ipaq_destroy_lists(port);
	kfree(priv);
	usb_set_serial_port_data(port, NULL);

	/* Uncomment the following line if you want to see some statistics in your syslog */
	/* info ("Bytes In = %d  Bytes Out = %d", bytes_in, bytes_out); */
}

static void ipaq_read_bulk_callback(struct urb *urb, struct pt_regs *regs)
{
	struct usb_serial_port	*port = (struct usb_serial_port *)urb->context;
	struct tty_struct	*tty;
	unsigned char		*data = urb->transfer_buffer;
	int			i, result;

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

	if (urb->status) {
		dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
		return;
	}

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

	tty = port->tty;
	if (tty && urb->actual_length) {
		for (i = 0; i < urb->actual_length ; ++i) {
			/* if we insert more than TTY_FLIPBUF_SIZE characters, we drop them. */
			if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
				tty_flip_buffer_push(tty);
			}
			/* this doesn't actually push the data through unless tty->low_latency is set */
			tty_insert_flip_char(tty, data[i], 0);
		}
		tty_flip_buffer_push(tty);
		bytes_in += urb->actual_length;
	}

	/* 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,
		      ipaq_read_bulk_callback, port);
	result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
	if (result)
		err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
	return;
}

static int ipaq_write(struct usb_serial_port *port, const unsigned char *buf,
		       int count)
{
	const unsigned char	*current_position = buf;
	int			bytes_sent = 0;
	int			transfer_size;

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

	while (count > 0) {
		transfer_size = min(count, PACKET_SIZE);
		if (ipaq_write_bulk(port, current_position, transfer_size)) {
			break;
		}
		current_position += transfer_size;
		bytes_sent += transfer_size;
		count -= transfer_size;
		bytes_out += transfer_size;
	}

	return bytes_sent;
} 

static int ipaq_write_bulk(struct usb_serial_port *port, const unsigned char *buf,
			   int count)
{
	struct ipaq_private	*priv = usb_get_serial_port_data(port);
	struct ipaq_packet	*pkt = NULL;
	int			result = 0;
	unsigned long		flags;

	if (priv->free_len <= 0) {
		dbg("%s - we're stuffed", __FUNCTION__);
		return -EAGAIN;
	}

	spin_lock_irqsave(&write_list_lock, flags);
	if (!list_empty(&priv->freelist)) {
		pkt = list_entry(priv->freelist.next, struct ipaq_packet, list);
		list_del(&pkt->list);
		priv->free_len -= PACKET_SIZE;
	}
	spin_unlock_irqrestore(&write_list_lock, flags);
	if (pkt == NULL) {
		dbg("%s - we're stuffed", __FUNCTION__);
		return -EAGAIN;
	}

	memcpy(pkt->data, buf, count);
	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, pkt->data);

	pkt->len = count;
	pkt->written = 0;
	spin_lock_irqsave(&write_list_lock, flags);
	list_add_tail(&pkt->list, &priv->queue);
	priv->queue_len += count;
	if (priv->active == 0) {
		priv->active = 1;
		ipaq_write_gather(port);
		spin_unlock_irqrestore(&write_list_lock, flags);
		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
		if (result) {
			err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
		}
	} else {
		spin_unlock_irqrestore(&write_list_lock, flags);
	}
	return result;
}

static void ipaq_write_gather(struct usb_serial_port *port)
{
	struct ipaq_private	*priv = usb_get_serial_port_data(port);
	struct usb_serial	*serial = port->serial;
	int			count, room;
	struct ipaq_packet	*pkt, *tmp;
	struct urb		*urb = port->write_urb;

	room = URBDATA_SIZE;
	list_for_each_entry_safe(pkt, tmp, &priv->queue, list) {
		count = min(room, (int)(pkt->len - pkt->written));
		memcpy(urb->transfer_buffer + (URBDATA_SIZE - room),
		       pkt->data + pkt->written, count);
		room -= count;
		pkt->written += count;
		priv->queue_len -= count;
		if (pkt->written == pkt->len) {
			list_move(&pkt->list, &priv->freelist);
			priv->free_len += PACKET_SIZE;
		}
		if (room == 0) {
			break;
		}
	}

	count = URBDATA_SIZE - room;
	usb_fill_bulk_urb(port->write_urb, serial->dev, 
		      usb_sndbulkpipe(serial->dev, port->bulk_out_endpointAddress),
		      port->write_urb->transfer_buffer, count, ipaq_write_bulk_callback,
		      port);
	return;
}

static void ipaq_write_bulk_callback(struct urb *urb, struct pt_regs *regs)
{
	struct usb_serial_port	*port = (struct usb_serial_port *)urb->context;
	struct ipaq_private	*priv = usb_get_serial_port_data(port);
	unsigned long		flags;
	int			result;

	dbg("%s - port %d", __FUNCTION__, port->number);
	
	if (urb->status) {
		dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
	}

	spin_lock_irqsave(&write_list_lock, flags);
	if (!list_empty(&priv->queue)) {
		ipaq_write_gather(port);
		spin_unlock_irqrestore(&write_list_lock, flags);
		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
		if (result) {
			err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
		}
	} else {
		priv->active = 0;
		spin_unlock_irqrestore(&write_list_lock, flags);
	}

	schedule_work(&port->work);
}

static int ipaq_write_room(struct usb_serial_port *port)
{
	struct ipaq_private	*priv = usb_get_serial_port_data(port);

	dbg("%s - freelen %d", __FUNCTION__, priv->free_len);
	return priv->free_len;
}

static int ipaq_chars_in_buffer(struct usb_serial_port *port)
{
	struct ipaq_private	*priv = usb_get_serial_port_data(port);

	dbg("%s - queuelen %d", __FUNCTION__, priv->queue_len);
	return priv->queue_len;
}

static void ipaq_destroy_lists(struct usb_serial_port *port)
{
	struct ipaq_private	*priv = usb_get_serial_port_data(port);
	struct ipaq_packet	*pkt, *tmp;

	list_for_each_entry_safe(pkt, tmp, &priv->queue, list) {
		kfree(pkt->data);
		kfree(pkt);
	}
	list_for_each_entry_safe(pkt, tmp, &priv->freelist, list) {
		kfree(pkt->data);
		kfree(pkt);
	}
}


static int ipaq_startup(struct usb_serial *serial)
{
	dbg("%s", __FUNCTION__);
	if (serial->dev->actconfig->desc.bConfigurationValue != 1) {
		err("active config #%d != 1 ??",
			serial->dev->actconfig->desc.bConfigurationValue);
		return -ENODEV;
	}
	return usb_reset_configuration (serial->dev);
}

static void ipaq_shutdown(struct usb_serial *serial)
{
	dbg("%s", __FUNCTION__);
}

static int __init ipaq_init(void)
{
	int retval;
	spin_lock_init(&write_list_lock);
	retval = usb_serial_register(&ipaq_device);
	if (retval) 
		goto failed_usb_serial_register;
	info(DRIVER_DESC " " DRIVER_VERSION);
	if (vendor) {
		ipaq_id_table[0].idVendor = vendor;
		ipaq_id_table[0].idProduct = product;
	}
	retval = usb_register(&ipaq_driver);
	if (retval)
		goto failed_usb_register;
		  
	return 0;
failed_usb_register:
	usb_serial_deregister(&ipaq_device);
failed_usb_serial_register:
	return retval;
}


static void __exit ipaq_exit(void)
{
	usb_deregister(&ipaq_driver);
	usb_serial_deregister(&ipaq_device);
}


module_init(ipaq_init);
module_exit(ipaq_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(vendor, ushort, 0);
MODULE_PARM_DESC(vendor, "User specified USB idVendor");

module_param(product, ushort, 0);
MODULE_PARM_DESC(product, "User specified USB idProduct");