visor.c

usb driver for 2.6.17

	dbg("%s - port %d", __FUNCTION__, port->number);
			 
	/* shutdown our urbs */
	usb_kill_urb(port->read_urb);
	if (port->interrupt_in_urb)
		usb_kill_urb(port->interrupt_in_urb);

	/* Try to send shutdown message, if the device is gone, this will just fail. */
	transfer_buffer =  kmalloc (0x12, GFP_KERNEL);
	if (transfer_buffer) {
		usb_control_msg (port->serial->dev,
				 usb_rcvctrlpipe(port->serial->dev, 0),
				 VISOR_CLOSE_NOTIFICATION, 0xc2,
				 0x0000, 0x0000, 
				 transfer_buffer, 0x12, 300);
		kfree (transfer_buffer);
	}

	if (stats)
		dev_info(&port->dev, "Bytes In = %d  Bytes Out = %d\n",
			 priv->bytes_in, priv->bytes_out);
}


static int visor_write (struct usb_serial_port *port, const unsigned char *buf, int count)
{
	struct visor_private *priv = usb_get_serial_port_data(port);
	struct usb_serial *serial = port->serial;
	struct urb *urb;
	unsigned char *buffer;
	unsigned long flags;
	int status;

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

	spin_lock_irqsave(&priv->lock, flags);
	if (priv->outstanding_urbs > URB_UPPER_LIMIT) {
		spin_unlock_irqrestore(&priv->lock, flags);
		dbg("%s - write limit hit\n", __FUNCTION__);
		return 0;
	}
	spin_unlock_irqrestore(&priv->lock, flags);

	buffer = kmalloc (count, GFP_ATOMIC);
	if (!buffer) {
		dev_err(&port->dev, "out of memory\n");
		return -ENOMEM;
	}

	urb = usb_alloc_urb(0, GFP_ATOMIC);
	if (!urb) {
		dev_err(&port->dev, "no more free urbs\n");
		kfree (buffer);
		return -ENOMEM;
	}

	memcpy (buffer, buf, count);

	usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, buffer);

	usb_fill_bulk_urb (urb, serial->dev,
			   usb_sndbulkpipe (serial->dev,
					    port->bulk_out_endpointAddress),
			   buffer, count, 
			   visor_write_bulk_callback, port);

	/* send it down the pipe */
	status = usb_submit_urb(urb, GFP_ATOMIC);
	if (status) {
		dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed with status = %d\n",
			__FUNCTION__, status);
		count = status;
		kfree (buffer);
	} else {
		spin_lock_irqsave(&priv->lock, flags);
		++priv->outstanding_urbs;
		priv->bytes_out += count;
		spin_unlock_irqrestore(&priv->lock, flags);
	}

	/* we are done with this urb, so let the host driver
	 * really free it when it is finished with it */
	usb_free_urb (urb);

	return count;
}


static int visor_write_room (struct usb_serial_port *port)
{
	dbg("%s - port %d", __FUNCTION__, port->number);

	/*
	 * We really can take anything the user throws at us
	 * but let's pick a nice big number to tell the tty
	 * layer that we have lots of free space
	 */
	return 2048;
}


static int visor_chars_in_buffer (struct usb_serial_port *port)
{
	dbg("%s - port %d", __FUNCTION__, port->number);

	/* 
	 * We can't really account for how much data we
	 * have sent out, but hasn't made it through to the
	 * device, so just tell the tty layer that everything
	 * is flushed.
	 */
	return 0;
}


static void visor_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
{
	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct visor_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;

	/* free up the transfer buffer, as usb_free_urb() does not do this */
	kfree (urb->transfer_buffer);

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

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

	schedule_work(&port->work);
}


static void visor_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
{
	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct visor_private *priv = usb_get_serial_port_data(port);
	unsigned char *data = urb->transfer_buffer;
	struct tty_struct *tty;
	unsigned long flags;
	int throttled;
	int 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) {
		tty_buffer_request_room(tty, urb->actual_length);
		tty_insert_flip_string(tty, data, urb->actual_length);
		tty_flip_buffer_push(tty);
	}
	spin_lock_irqsave(&priv->lock, flags);
	priv->bytes_in += urb->actual_length;
	throttled = priv->throttled;
	spin_unlock_irqrestore(&priv->lock, flags);

	/* Continue trying to always read if we should */
	if (!throttled) {
		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,
				   visor_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);
	}
	return;
}

static void visor_read_int_callback (struct urb *urb, struct pt_regs *regs)
{
	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	int result;

	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;
	}

	/*
	 * This information is still unknown what it can be used for.
	 * If anyone has an idea, please let the author know...
	 *
	 * Rumor has it this endpoint is used to notify when data
	 * is ready to be read from the bulk ones.
	 */
	usb_serial_debug_data(debug, &port->dev, __FUNCTION__,
			      urb->actual_length, urb->transfer_buffer);

exit:
	result = usb_submit_urb (urb, GFP_ATOMIC);
	if (result)
		dev_err(&urb->dev->dev, "%s - Error %d submitting interrupt urb\n",
			__FUNCTION__, result);
}

static void visor_throttle (struct usb_serial_port *port)
{
	struct visor_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;

	dbg("%s - port %d", __FUNCTION__, port->number);
	spin_lock_irqsave(&priv->lock, flags);
	priv->throttled = 1;
	spin_unlock_irqrestore(&priv->lock, flags);
}


static void visor_unthrottle (struct usb_serial_port *port)
{
	struct visor_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;
	int result;

	dbg("%s - port %d", __FUNCTION__, port->number);
	spin_lock_irqsave(&priv->lock, flags);
	priv->throttled = 0;
	spin_unlock_irqrestore(&priv->lock, flags);

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

static int palm_os_3_probe (struct usb_serial *serial, const struct usb_device_id *id)
{
	struct device *dev = &serial->dev->dev;
	struct visor_connection_info *connection_info;
	unsigned char *transfer_buffer;
	char *string;
	int retval = 0;
	int i;
	int num_ports = 0;

	dbg("%s", __FUNCTION__);

	transfer_buffer = kmalloc (sizeof (*connection_info), GFP_KERNEL);
	if (!transfer_buffer) {
		dev_err(dev, "%s - kmalloc(%Zd) failed.\n", __FUNCTION__,
			sizeof(*connection_info));
		return -ENOMEM;
	}

	/* send a get connection info request */
	retval = usb_control_msg (serial->dev,
				  usb_rcvctrlpipe(serial->dev, 0),
				  VISOR_GET_CONNECTION_INFORMATION,
				  0xc2, 0x0000, 0x0000, transfer_buffer,
				  sizeof(*connection_info), 300);
	if (retval < 0) {
		dev_err(dev, "%s - error %d getting connection information\n",
			__FUNCTION__, retval);
		goto exit;
	}

	if (retval == sizeof(*connection_info)) {
	        connection_info = (struct visor_connection_info *)transfer_buffer;

		num_ports = le16_to_cpu(connection_info->num_ports);
		for (i = 0; i < num_ports; ++i) {
			switch (connection_info->connections[i].port_function_id) {
				case VISOR_FUNCTION_GENERIC:
					string = "Generic";
					break;
				case VISOR_FUNCTION_DEBUGGER:
					string = "Debugger";
					break;
				case VISOR_FUNCTION_HOTSYNC:
					string = "HotSync";
					break;
				case VISOR_FUNCTION_CONSOLE:
					string = "Console";
					break;
				case VISOR_FUNCTION_REMOTE_FILE_SYS:
					string = "Remote File System";
					break;
				default:
					string = "unknown";
					break;
			}
			dev_info(dev, "%s: port %d, is for %s use\n",
				serial->type->description,
				connection_info->connections[i].port, string);
		}
	}
	/*
	* Handle devices that report invalid stuff here.
	*/
	if (num_ports == 0 || num_ports > 2) {
		dev_warn (dev, "%s: No valid connect info available\n",
			serial->type->description);
		num_ports = 2;
	}
  
	dev_info(dev, "%s: Number of ports: %d\n", serial->type->description,
		num_ports);

	/*
	 * save off our num_ports info so that we can use it in the
	 * calc_num_ports callback
	 */
	usb_set_serial_data(serial, (void *)(long)num_ports);

	/* ask for the number of bytes available, but ignore the response as it is broken */
	retval = usb_control_msg (serial->dev,
				  usb_rcvctrlpipe(serial->dev, 0),
				  VISOR_REQUEST_BYTES_AVAILABLE,
				  0xc2, 0x0000, 0x0005, transfer_buffer,
				  0x02, 300);
	if (retval < 0)
		dev_err(dev, "%s - error %d getting bytes available request\n",
			__FUNCTION__, retval);
	retval = 0;

exit:
	kfree (transfer_buffer);

	return retval;
}