irda-usb.c

《linux驱动程序设计从入门到精通》一书中所有的程序代码含驱动和相应的应用程序

	kfree(self->speed_buff);
	self->speed_buff = NULL;

	kfree(self->tx_buff);
	self->tx_buff = NULL;
}

/********************** USB CONFIG SUBROUTINES **********************/
/*
 * Various subroutines dealing with USB stuff we use to configure and
 * initialise each irda-usb instance.
 * These functions are used below in the main calls of the driver...
 */

/*------------------------------------------------------------------*/
/*
 * Function irda_usb_parse_endpoints(dev, ifnum)
 *
 *    Parse the various endpoints and find the one we need.
 *
 * The endpoint are the pipes used to communicate with the USB device.
 * The spec defines 2 endpoints of type bulk transfer, one in, and one out.
 * These are used to pass frames back and forth with the dongle.
 * Most dongle have also an interrupt endpoint, that will be probably
 * documented in the next spec...
 */
static inline int irda_usb_parse_endpoints(struct irda_usb_cb *self, struct usb_host_endpoint *endpoint, int ennum)
{
	int i;		/* Endpoint index in table */
		
	/* Init : no endpoints */
	self->bulk_in_ep = 0;
	self->bulk_out_ep = 0;
	self->bulk_int_ep = 0;

	/* Let's look at all those endpoints */
	for(i = 0; i < ennum; i++) {
		/* All those variables will get optimised by the compiler,
		 * so let's aim for clarity... - Jean II */
		__u8 ep;	/* Endpoint address */
		__u8 dir;	/* Endpoint direction */
		__u8 attr;	/* Endpoint attribute */
		__u16 psize;	/* Endpoint max packet size in bytes */

		/* Get endpoint address, direction and attribute */
		ep = endpoint[i].desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
		dir = endpoint[i].desc.bEndpointAddress & USB_ENDPOINT_DIR_MASK;
		attr = endpoint[i].desc.bmAttributes;
		psize = le16_to_cpu(endpoint[i].desc.wMaxPacketSize);

		/* Is it a bulk endpoint ??? */
		if(attr == USB_ENDPOINT_XFER_BULK) {
			/* We need to find an IN and an OUT */
			if(dir == USB_DIR_IN) {
				/* This is our Rx endpoint */
				self->bulk_in_ep = ep;
			} else {
				/* This is our Tx endpoint */
				self->bulk_out_ep = ep;
				self->bulk_out_mtu = psize;
			}
		} else {
			if((attr == USB_ENDPOINT_XFER_INT) &&
			   (dir == USB_DIR_IN)) {
				/* This is our interrupt endpoint */
				self->bulk_int_ep = ep;
			} else {
				IRDA_ERROR("%s(), Unrecognised endpoint %02X.\n", __FUNCTION__, ep);
			}
		}
	}

	IRDA_DEBUG(0, "%s(), And our endpoints are : in=%02X, out=%02X (%d), int=%02X\n",
		__FUNCTION__, self->bulk_in_ep, self->bulk_out_ep, self->bulk_out_mtu, self->bulk_int_ep);

	return((self->bulk_in_ep != 0) && (self->bulk_out_ep != 0));
}

#ifdef IU_DUMP_CLASS_DESC
/*------------------------------------------------------------------*/
/*
 * Function usb_irda_dump_class_desc(desc)
 *
 *    Prints out the contents of the IrDA class descriptor
 *
 */
static inline void irda_usb_dump_class_desc(struct irda_class_desc *desc)
{
	/* Values are little endian */
	printk("bLength=%x\n", desc->bLength);
	printk("bDescriptorType=%x\n", desc->bDescriptorType);
	printk("bcdSpecRevision=%x\n", le16_to_cpu(desc->bcdSpecRevision)); 
	printk("bmDataSize=%x\n", desc->bmDataSize);
	printk("bmWindowSize=%x\n", desc->bmWindowSize);
	printk("bmMinTurnaroundTime=%d\n", desc->bmMinTurnaroundTime);
	printk("wBaudRate=%x\n", le16_to_cpu(desc->wBaudRate));
	printk("bmAdditionalBOFs=%x\n", desc->bmAdditionalBOFs);
	printk("bIrdaRateSniff=%x\n", desc->bIrdaRateSniff);
	printk("bMaxUnicastList=%x\n", desc->bMaxUnicastList);
}
#endif /* IU_DUMP_CLASS_DESC */

/*------------------------------------------------------------------*/
/*
 * Function irda_usb_find_class_desc(intf)
 *
 *    Returns instance of IrDA class descriptor, or NULL if not found
 *
 * The class descriptor is some extra info that IrDA USB devices will
 * offer to us, describing their IrDA characteristics. We will use that in
 * irda_usb_init_qos()
 */
static inline struct irda_class_desc *irda_usb_find_class_desc(struct usb_interface *intf)
{
	struct usb_device *dev = interface_to_usbdev (intf);
	struct irda_class_desc *desc;
	int ret;

	desc = kmalloc(sizeof (*desc), GFP_KERNEL);
	if (desc == NULL) 
		return NULL;
	memset(desc, 0, sizeof(*desc));

	/* USB-IrDA class spec 1.0:
	 *	6.1.3: Standard "Get Descriptor" Device Request is not
	 *	       appropriate to retrieve class-specific descriptor
	 *	6.2.5: Class Specific "Get Class Descriptor" Interface Request
	 *	       is mandatory and returns the USB-IrDA class descriptor
	 */

	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev,0),
		IU_REQ_GET_CLASS_DESC,
		USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
		0, intf->altsetting->desc.bInterfaceNumber, desc,
		sizeof(*desc), 500);
	
	IRDA_DEBUG(1, "%s(), ret=%d\n", __FUNCTION__, ret);
	if (ret < sizeof(*desc)) {
		IRDA_WARNING("usb-irda: class_descriptor read %s (%d)\n",
			     (ret<0) ? "failed" : "too short", ret);
	}
	else if (desc->bDescriptorType != USB_DT_IRDA) {
		IRDA_WARNING("usb-irda: bad class_descriptor type\n");
	}
	else {
#ifdef IU_DUMP_CLASS_DESC
		irda_usb_dump_class_desc(desc);
#endif	/* IU_DUMP_CLASS_DESC */

		return desc;
	}
	kfree(desc);
	return NULL;
}

/*********************** USB DEVICE CALLBACKS ***********************/
/*
 * Main calls from the USB subsystem.
 * Mostly registering a new irda-usb device and removing it....
 */

/*------------------------------------------------------------------*/
/*
 * This routine is called by the USB subsystem for each new device
 * in the system. We need to check if the device is ours, and in
 * this case start handling it.
 * The USB layer protect us from reentrancy (via BKL), so we don't need
 * to spinlock in there... Jean II
 */
static int irda_usb_probe(struct usb_interface *intf,
			  const struct usb_device_id *id)
{
	struct net_device *net;
	struct usb_device *dev = interface_to_usbdev(intf);
	struct irda_usb_cb *self = NULL;
	struct usb_host_interface *interface;
	struct irda_class_desc *irda_desc;
	int ret = -ENOMEM;
	int i;		/* Driver instance index / Rx URB index */

	/* Note : the probe make sure to call us only for devices that
	 * matches the list of dongle (top of the file). So, we
	 * don't need to check if the dongle is really ours.
	 * Jean II */

	IRDA_MESSAGE("IRDA-USB found at address %d, Vendor: %x, Product: %x\n",
		     dev->devnum, le16_to_cpu(dev->descriptor.idVendor),
		     le16_to_cpu(dev->descriptor.idProduct));

	net = alloc_irdadev(sizeof(*self));
	if (!net) 
		goto err_out;

	SET_MODULE_OWNER(net);
	SET_NETDEV_DEV(net, &intf->dev);
	self = net->priv;
	self->netdev = net;
	spin_lock_init(&self->lock);
	init_timer(&self->rx_defer_timer);

	self->capability = id->driver_info;
	self->needspatch = ((self->capability & IUC_STIR421X) != 0);

	/* Create all of the needed urbs */
	if (self->capability & IUC_STIR421X) {
		self->max_rx_urb = IU_SIGMATEL_MAX_RX_URBS;
		self->header_length = USB_IRDA_STIR421X_HEADER;
	} else {
		self->max_rx_urb = IU_MAX_RX_URBS;
		self->header_length = USB_IRDA_HEADER;
	}

	self->rx_urb = kzalloc(self->max_rx_urb * sizeof(struct urb *),
				GFP_KERNEL);

	for (i = 0; i < self->max_rx_urb; i++) {
		self->rx_urb[i] = usb_alloc_urb(0, GFP_KERNEL);
		if (!self->rx_urb[i]) {
			goto err_out_1;
		}
	}
	self->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!self->tx_urb) {
		goto err_out_1;
	}
	self->speed_urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!self->speed_urb) {
		goto err_out_2;
	}

	/* Is this really necessary? (no, except maybe for broken devices) */
	if (usb_reset_configuration (dev) < 0) {
		err("reset_configuration failed");
		ret = -EIO;
		goto err_out_3;
	}

	/* Is this really necessary? */
	/* Note : some driver do hardcode the interface number, some others
	 * specify an alternate, but very few driver do like this.
	 * Jean II */
	ret = usb_set_interface(dev, intf->altsetting->desc.bInterfaceNumber, 0);
	IRDA_DEBUG(1, "usb-irda: set interface %d result %d\n", intf->altsetting->desc.bInterfaceNumber, ret);
	switch (ret) {
		case 0:
			break;
		case -EPIPE:		/* -EPIPE = -32 */
			/* Martin Diehl says if we get a -EPIPE we should
			 * be fine and we don't need to do a usb_clear_halt().
			 * - Jean II */
			IRDA_DEBUG(0, "%s(), Received -EPIPE, ignoring...\n", __FUNCTION__);
			break;
		default:
			IRDA_DEBUG(0, "%s(), Unknown error %d\n", __FUNCTION__, ret);
			ret = -EIO;
			goto err_out_3;
	}

	/* Find our endpoints */
	interface = intf->cur_altsetting;
	if(!irda_usb_parse_endpoints(self, interface->endpoint,
				     interface->desc.bNumEndpoints)) {
		IRDA_ERROR("%s(), Bogus endpoints...\n", __FUNCTION__);
		ret = -EIO;
		goto err_out_3;
	}

	self->usbdev = dev;

	/* Find IrDA class descriptor */
	irda_desc = irda_usb_find_class_desc(intf);
	ret = -ENODEV;
	if (irda_desc == NULL)
		goto err_out_3;

	if (self->needspatch) {
		ret = usb_control_msg (self->usbdev, usb_sndctrlpipe (self->usbdev, 0),
				       0x02, 0x40, 0, 0, NULL, 0, 500);
		if (ret < 0) {
			IRDA_DEBUG (0, "usb_control_msg failed %d\n", ret);
			goto err_out_3;
		} else {
			mdelay(10);
		}
	}

	self->irda_desc =  irda_desc;
	self->present = 1;
	self->netopen = 0;
	self->usbintf = intf;

	/* Allocate the buffer for speed changes */
	/* Don't change this buffer size and allocation without doing
	 * some heavy and complete testing. Don't ask why :-(
	 * Jean II */
	self->speed_buff = kmalloc(IRDA_USB_SPEED_MTU, GFP_KERNEL);
	if (self->speed_buff == NULL) 
		goto err_out_3;

	memset(self->speed_buff, 0, IRDA_USB_SPEED_MTU);

	self->tx_buff = kzalloc(IRDA_SKB_MAX_MTU + self->header_length,
				GFP_KERNEL);
	if (self->tx_buff == NULL)
		goto err_out_4;

	ret = irda_usb_open(self);
	if (ret) 
		goto err_out_5;

	IRDA_MESSAGE("IrDA: Registered device %s\n", net->name);
	usb_set_intfdata(intf, self);

	if (self->needspatch) {
		/* Now we fetch and upload the firmware patch */
		ret = stir421x_patch_device(self);
		self->needspatch = (ret < 0);
		if (self->needspatch) {
			IRDA_ERROR("STIR421X: Couldn't upload patch\n");
			goto err_out_6;
		}

		/* replace IrDA class descriptor with what patched device is now reporting */
		irda_desc = irda_usb_find_class_desc (self->usbintf);
		if (irda_desc == NULL) {
			ret = -ENODEV;
			goto err_out_6;
		}
		if (self->irda_desc)
			kfree (self->irda_desc);
		self->irda_desc = irda_desc;
		irda_usb_init_qos(self);
	}

	return 0;
err_out_6:
	unregister_netdev(self->netdev);
err_out_5:
	kfree(self->tx_buff);
err_out_4:
	kfree(self->speed_buff);
err_out_3:
	/* Free all urbs that we may have created */
	usb_free_urb(self->speed_urb);
err_out_2:
	usb_free_urb(self->tx_urb);
err_out_1:
	for (i = 0; i < self->max_rx_urb; i++)
		usb_free_urb(self->rx_urb[i]);
	free_netdev(net);
err_out:
	return ret;
}

/*------------------------------------------------------------------*/
/*
 * The current irda-usb device is removed, the USB layer tell us
 * to shut it down...
 * One of the constraints is that when we exit this function,
 * we cannot use the usb_device no more. Gone. Destroyed. kfree().
 * Most other subsystem allow you to destroy the instance at a time
 * when it's convenient to you, to postpone it to a later date, but
 * not the USB subsystem.
 * So, we must make bloody sure that everything gets deactivated.
 * Jean II
 */
static void irda_usb_disconnect(struct usb_interface *intf)
{
	unsigned long flags;
	struct irda_usb_cb *self = usb_get_intfdata(intf);
	int i;

	IRDA_DEBUG(1, "%s()\n", __FUNCTION__);

	usb_set_intfdata(intf, NULL);
	if (!self)
		return;

	/* Make sure that the Tx path is not executing. - Jean II */
	spin_lock_irqsave(&self->lock, flags);

	/* Oups ! We are not there any more.
	 * This will stop/desactivate the Tx path. - Jean II */
	self->present = 0;

	/* Kill defered Rx URB */
	del_timer(&self->rx_defer_timer);

	/* We need to have irq enabled to unlink the URBs. That's OK,
	 * at this point the Tx path is gone - Jean II */
	spin_unlock_irqrestore(&self->lock, flags);

	/* Hum... Check if networking is still active (avoid races) */
	if((self->netopen) || (self->irlap)) {
		/* Accept no more transmissions */
		/*netif_device_detach(self->netdev);*/
		netif_stop_queue(self->netdev);
		/* Stop all the receive URBs. Must be synchronous. */
		for (i = 0; i < self->max_rx_urb; i++)
			usb_kill_urb(self->rx_urb[i]);
		/* Cancel Tx and speed URB.
		 * Make sure it's synchronous to avoid races. */
		usb_kill_urb(self->tx_urb);
		usb_kill_urb(self->speed_urb);
	}

	/* Cleanup the device stuff */
	irda_usb_close(self);
	/* No longer attached to USB bus */
	self->usbdev = NULL;
	self->usbintf = NULL;

	/* Clean up our urbs */
	for (i = 0; i < self->max_rx_urb; i++)
		usb_free_urb(self->rx_urb[i]);
	kfree(self->rx_urb);
	/* Clean up Tx and speed URB */
	usb_free_urb(self->tx_urb);
	usb_free_urb(self->speed_urb);

	/* Free self and network device */
	free_netdev(self->netdev);
	IRDA_DEBUG(0, "%s(), USB IrDA Disconnected\n", __FUNCTION__);
}

/*------------------------------------------------------------------*/
/*
 * USB device callbacks
 */
static struct usb_driver irda_driver = {
	.name		= "irda-usb",
	.probe		= irda_usb_probe,
	.disconnect	= irda_usb_disconnect,
	.id_table	= dongles,
};

/************************* MODULE CALLBACKS *************************/
/*
 * Deal with module insertion/removal
 * Mostly tell USB about our existence
 */

/*------------------------------------------------------------------*/
/*
 * Module insertion
 */
static int __init usb_irda_init(void)
{
	int	ret;

	ret = usb_register(&irda_driver);
	if (ret < 0)
		return ret;

	IRDA_MESSAGE("USB IrDA support registered\n");
	return 0;
}
module_init(usb_irda_init);

/*------------------------------------------------------------------*/
/*
 * Module removal
 */
static void __exit usb_irda_cleanup(void)
{
	/* Deregister the driver and remove all pending instances */
	usb_deregister(&irda_driver);
}
module_exit(usb_irda_cleanup);

/*------------------------------------------------------------------*/
/*
 * Module parameters
 */
module_param(qos_mtt_bits, int, 0);
MODULE_PARM_DESC(qos_mtt_bits, "Minimum Turn Time");
MODULE_AUTHOR("Roman Weissgaerber <[e-mail]>, Dag Brattli <[e-mail]>, Jean Tourrilhes <[e-mail]> and Nick Fedchik <[e-mail]>");
MODULE_DESCRIPTION("IrDA-USB Dongle Driver");
MODULE_LICENSE("GPL");