hci_usb.c

嵌入式Linux的蓝牙模块驱动

	urb->transfer_buffer = skb->data;
	urb->transfer_buffer_length = skb->len;

	__fill_isoc_desc(urb, skb->len, husb->isoc_out_ep->desc.wMaxPacketSize);

	_urb->priv = skb;
	return __tx_submit(husb, _urb);
}
#endif

static void hci_usb_tx_process(struct hci_usb *husb)
{
	struct sk_buff_head *q;
	struct sk_buff *skb;

	BT_DBG("%s", husb->hdev->name);

	do {
		clear_bit(HCI_USB_TX_WAKEUP, &husb->state);

		/* Process command queue */
		q = __transmit_q(husb, HCI_COMMAND_PKT);
		if (!atomic_read(__pending_tx(husb, HCI_COMMAND_PKT)) &&
				(skb = skb_dequeue(q))) {
			if (hci_usb_send_ctrl(husb, skb) < 0)
				skb_queue_head(q, skb);
		}

#ifdef CONFIG_BT_HCIUSB_SCO
		/* Process SCO queue */
		q = __transmit_q(husb, HCI_SCODATA_PKT);
		if (atomic_read(__pending_tx(husb, HCI_SCODATA_PKT)) < HCI_MAX_ISOC_TX &&
				(skb = skb_dequeue(q))) {
			if (hci_usb_send_isoc(husb, skb) < 0)
				skb_queue_head(q, skb);
		}
#endif

		/* Process ACL queue */
		q = __transmit_q(husb, HCI_ACLDATA_PKT);
		while (atomic_read(__pending_tx(husb, HCI_ACLDATA_PKT)) < HCI_MAX_BULK_TX &&
				(skb = skb_dequeue(q))) {
			if (hci_usb_send_bulk(husb, skb) < 0) {
				skb_queue_head(q, skb);
				break;
			}
		}
	} while(test_bit(HCI_USB_TX_WAKEUP, &husb->state));
}

static inline void hci_usb_tx_wakeup(struct hci_usb *husb)
{
	/* Serialize TX queue processing to avoid data reordering */
	if (!test_and_set_bit(HCI_USB_TX_PROCESS, &husb->state)) {
		hci_usb_tx_process(husb);
		clear_bit(HCI_USB_TX_PROCESS, &husb->state);
	} else
		set_bit(HCI_USB_TX_WAKEUP, &husb->state);
}

/* Send frames from HCI layer */
static int hci_usb_send_frame(struct sk_buff *skb)
{
	struct hci_dev *hdev = (struct hci_dev *) skb->dev;
	struct hci_usb *husb;

	if (!hdev) {
		BT_ERR("frame for uknown device (hdev=NULL)");
		return -ENODEV;
	}

	if (!test_bit(HCI_RUNNING, &hdev->flags))
		return -EBUSY;

	BT_DBG("%s type %d len %d", hdev->name, skb->pkt_type, skb->len);

	husb = (struct hci_usb *) hdev->driver_data;

	switch (skb->pkt_type) {
	case HCI_COMMAND_PKT:
		hdev->stat.cmd_tx++;
		break;

	case HCI_ACLDATA_PKT:
		hdev->stat.acl_tx++;
		break;

#ifdef CONFIG_BT_HCIUSB_SCO
	case HCI_SCODATA_PKT:
		hdev->stat.sco_tx++;
		break;
#endif

	default:
		kfree_skb(skb);
		return 0;
	}

	read_lock(&husb->completion_lock);

	skb_queue_tail(__transmit_q(husb, skb->pkt_type), skb);
	hci_usb_tx_wakeup(husb);

	read_unlock(&husb->completion_lock);
	return 0;
}

static inline int __recv_frame(struct hci_usb *husb, int type, void *data, int count)
{
	BT_DBG("%s type %d data %p count %d", husb->hdev->name, type, data, count);

	husb->hdev->stat.byte_rx += count;

	while (count) {
		struct sk_buff *skb = __reassembly(husb, type);
		struct { int expect; } *scb;
		int len = 0;
	
		if (!skb) {
			/* Start of the frame */

			switch (type) {
			case HCI_EVENT_PKT:
				if (count >= HCI_EVENT_HDR_SIZE) {
					struct hci_event_hdr *h = data;
					len = HCI_EVENT_HDR_SIZE + h->plen;
				} else
					return -EILSEQ;
				break;

			case HCI_ACLDATA_PKT:
				if (count >= HCI_ACL_HDR_SIZE) {
					struct hci_acl_hdr *h = data;
					len = HCI_ACL_HDR_SIZE + __le16_to_cpu(h->dlen);
				} else
					return -EILSEQ;
				break;
#ifdef CONFIG_BT_HCIUSB_SCO
			case HCI_SCODATA_PKT:
				if (count >= HCI_SCO_HDR_SIZE) {
					struct hci_sco_hdr *h = data;
					len = HCI_SCO_HDR_SIZE + h->dlen;
				} else
					return -EILSEQ;
				break;
#endif
			}
			BT_DBG("new packet len %d", len);

			skb = bt_skb_alloc(len, GFP_ATOMIC);
			if (!skb) {
				BT_ERR("%s no memory for the packet", husb->hdev->name);
				return -ENOMEM;
			}
			skb->dev = (void *) husb->hdev;
			skb->pkt_type = type;
	
			__reassembly(husb, type) = skb;

			scb = (void *) skb->cb;
			scb->expect = len;
		} else {
			/* Continuation */
			scb = (void *) skb->cb;
			len = scb->expect;
		}

		len = min(len, count);
		
		memcpy(skb_put(skb, len), data, len);

		scb->expect -= len;
		if (!scb->expect) {
			/* Complete frame */
			__reassembly(husb, type) = NULL;
			hci_recv_frame(skb);
		}

		count -= len; data += len;
	}
	return 0;
}

static void hci_usb_rx_complete(struct urb *urb, struct pt_regs *regs)
{
	struct _urb *_urb = container_of(urb, struct _urb, urb);
	struct hci_usb *husb = (void *) urb->context;
	struct hci_dev *hdev = husb->hdev;
	int err, count = urb->actual_length;

	BT_DBG("%s urb %p type %d status %d count %d flags %x", hdev->name, urb,
			_urb->type, urb->status, count, urb->transfer_flags);

	read_lock(&husb->completion_lock);

	if (!test_bit(HCI_RUNNING, &hdev->flags))
		goto unlock;

	if (urb->status || !count)
		goto resubmit;

	if (_urb->type == HCI_SCODATA_PKT) {
#ifdef CONFIG_BT_HCIUSB_SCO
		int i;
		for (i=0; i < urb->number_of_packets; i++) {
			BT_DBG("desc %d status %d offset %d len %d", i,
					urb->iso_frame_desc[i].status,
					urb->iso_frame_desc[i].offset,
					urb->iso_frame_desc[i].actual_length);
	
			if (!urb->iso_frame_desc[i].status)
				__recv_frame(husb, _urb->type, 
					urb->transfer_buffer + urb->iso_frame_desc[i].offset,
					urb->iso_frame_desc[i].actual_length);
		}
#else
		;
#endif
	} else {
		err = __recv_frame(husb, _urb->type, urb->transfer_buffer, count);
		if (err < 0) { 
			BT_ERR("%s corrupted packet: type %d count %d",
					husb->hdev->name, _urb->type, count);
			hdev->stat.err_rx++;
		}
	}

resubmit:
	urb->dev = husb->udev;
	err = usb_submit_urb(urb, GFP_ATOMIC);
	BT_DBG("%s urb %p type %d resubmit status %d", hdev->name, urb,
			_urb->type, err);

unlock:
	read_unlock(&husb->completion_lock);
}

static void hci_usb_tx_complete(struct urb *urb, struct pt_regs *regs)
{
	struct _urb *_urb = container_of(urb, struct _urb, urb);
	struct hci_usb *husb = (void *) urb->context;
	struct hci_dev *hdev = husb->hdev;

	BT_DBG("%s urb %p status %d flags %x", hdev->name, urb,
			urb->status, urb->transfer_flags);

	atomic_dec(__pending_tx(husb, _urb->type));

	urb->transfer_buffer = NULL;
	kfree_skb((struct sk_buff *) _urb->priv);

	if (!test_bit(HCI_RUNNING, &hdev->flags))
		return;

	if (!urb->status)
		hdev->stat.byte_tx += urb->transfer_buffer_length;
	else
		hdev->stat.err_tx++;

	read_lock(&husb->completion_lock);

	_urb_unlink(_urb);
	_urb_queue_tail(__completed_q(husb, _urb->type), _urb);

	hci_usb_tx_wakeup(husb);

	read_unlock(&husb->completion_lock);
}

static void hci_usb_destruct(struct hci_dev *hdev)
{
	struct hci_usb *husb = (struct hci_usb *) hdev->driver_data;

	BT_DBG("%s", hdev->name);

	kfree(husb);
}

int hci_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
	struct usb_device *udev = interface_to_usbdev(intf);
	struct usb_host_endpoint *bulk_out_ep = NULL;
	struct usb_host_endpoint *bulk_in_ep = NULL;
	struct usb_host_endpoint *intr_in_ep = NULL;
	struct usb_host_endpoint  *ep;
	struct usb_host_interface *uif;
	struct usb_interface *isoc_iface;
	struct hci_usb *husb;
	struct hci_dev *hdev;
	int i, e, size, isoc_ifnum, isoc_alts;

	BT_DBG("udev %p intf %p", udev, intf);

	if (!id->driver_info) {
		const struct usb_device_id *match;
		match = usb_match_id(intf, blacklist_ids);
		if (match)
			id = match;
	}

	if (id->driver_info & HCI_IGNORE)
		return -ENODEV;

	if (intf->cur_altsetting->desc.bInterfaceNumber > 0)
		return -ENODEV;

	/* Find endpoints that we need */
	uif = intf->cur_altsetting;
	for (e = 0; e < uif->desc.bNumEndpoints; e++) {
		ep = &uif->endpoint[e];

		switch (ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
		case USB_ENDPOINT_XFER_INT:
			if (ep->desc.bEndpointAddress & USB_DIR_IN)
				intr_in_ep = ep;
			break;

		case USB_ENDPOINT_XFER_BULK:
			if (ep->desc.bEndpointAddress & USB_DIR_IN)
				bulk_in_ep  = ep;
			else
				bulk_out_ep = ep;
			break;
		}
	}

	if (!bulk_in_ep || !bulk_out_ep || !intr_in_ep) {
		BT_DBG("Bulk endpoints not found");
		goto done;
	}

	if (!(husb = kmalloc(sizeof(struct hci_usb), GFP_KERNEL))) {
		BT_ERR("Can't allocate: control structure");
		goto done;
	}

	memset(husb, 0, sizeof(struct hci_usb));

	husb->udev = udev;
	husb->bulk_out_ep = bulk_out_ep;
	husb->bulk_in_ep  = bulk_in_ep;
	husb->intr_in_ep  = intr_in_ep;

	if (id->driver_info & HCI_DIGIANSWER)
		husb->ctrl_req = HCI_DIGI_REQ;
	else
		husb->ctrl_req = HCI_CTRL_REQ;

	/* Find isochronous endpoints that we can use */
	size = 0; 
	isoc_iface = NULL;
	isoc_alts  = 0;
	isoc_ifnum = 1;

#ifdef CONFIG_BT_HCIUSB_SCO
	if (!(id->driver_info & HCI_BROKEN_ISOC))
		isoc_iface = usb_ifnum_to_if(udev, isoc_ifnum);

	if (isoc_iface) {
		int a;
		struct usb_host_endpoint *isoc_out_ep = NULL;
		struct usb_host_endpoint *isoc_in_ep = NULL;

		for (a = 0; a < isoc_iface->num_altsetting; a++) {
			uif = &isoc_iface->altsetting[a];
			for (e = 0; e < uif->desc.bNumEndpoints; e++) {
				ep = &uif->endpoint[e];

				switch (ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
				case USB_ENDPOINT_XFER_ISOC:
					if (ep->desc.wMaxPacketSize < size ||
							uif->desc.bAlternateSetting > 2)
						break;
					size = ep->desc.wMaxPacketSize;

					isoc_alts = uif->desc.bAlternateSetting;

					if (ep->desc.bEndpointAddress & USB_DIR_IN)
						isoc_in_ep  = ep;
					else
						isoc_out_ep = ep;
					break;
				}
			}
		}

		if (!isoc_in_ep || !isoc_out_ep)
			BT_DBG("Isoc endpoints not found");
		else {
			BT_DBG("isoc ifnum %d alts %d", isoc_ifnum, isoc_alts);
			if (usb_driver_claim_interface(&hci_usb_driver, isoc_iface, husb) != 0)
				BT_ERR("Can't claim isoc interface");
			else if (usb_set_interface(udev, isoc_ifnum, isoc_alts)) {
				BT_ERR("Can't set isoc interface settings");
				usb_driver_release_interface(&hci_usb_driver, isoc_iface);
			} else {
				husb->isoc_iface  = isoc_iface;
				husb->isoc_in_ep  = isoc_in_ep;
				husb->isoc_out_ep = isoc_out_ep;
			}
		}
	}
#endif

	husb->completion_lock = RW_LOCK_UNLOCKED;

	for (i = 0; i < 4; i++) {
		skb_queue_head_init(&husb->transmit_q[i]);
		_urb_queue_init(&husb->pending_q[i]);
		_urb_queue_init(&husb->completed_q[i]);
	}

	/* Initialize and register HCI device */
	hdev = hci_alloc_dev();
	if (!hdev) {
		BT_ERR("Can't allocate HCI device");
		goto probe_error;
	}

	husb->hdev = hdev;

	hdev->type = HCI_USB;
	hdev->driver_data = husb;
	SET_HCIDEV_DEV(hdev, &intf->dev);

	hdev->open     = hci_usb_open;
	hdev->close    = hci_usb_close;
	hdev->flush    = hci_usb_flush;
	hdev->send     = hci_usb_send_frame;
	hdev->destruct = hci_usb_destruct;

	hdev->owner = THIS_MODULE;

	if (id->driver_info & HCI_RESET)
		set_bit(HCI_QUIRK_RESET_ON_INIT, &hdev->quirks);

	if (hci_register_dev(hdev) < 0) {
		BT_ERR("Can't register HCI device");
		hci_free_dev(hdev);
		goto probe_error;
	}

	usb_set_intfdata(intf, husb);
	return 0;

probe_error:
	if (husb->isoc_iface)
		usb_driver_release_interface(&hci_usb_driver, husb->isoc_iface);
	kfree(husb);

done:
	return -EIO;
}

static void hci_usb_disconnect(struct usb_interface *intf)
{
	struct hci_usb *husb = usb_get_intfdata(intf);
	struct hci_dev *hdev;

	if (!husb || intf == husb->isoc_iface)
		return;

	usb_set_intfdata(intf, NULL);
	hdev = husb->hdev;

	BT_DBG("%s", hdev->name);

	hci_usb_close(hdev);

	if (husb->isoc_iface)
		usb_driver_release_interface(&hci_usb_driver, husb->isoc_iface);

	if (hci_unregister_dev(hdev) < 0)
		BT_ERR("Can't unregister HCI device %s", hdev->name);

	hci_free_dev(hdev);
}

static struct usb_driver hci_usb_driver = {
	.owner		= THIS_MODULE,
	.name		= "hci_usb",
	.probe		= hci_usb_probe,
	.disconnect	= hci_usb_disconnect,
	.id_table	= bluetooth_ids,
};

static int __init hci_usb_init(void)
{
	int err;

	BT_INFO("HCI USB driver ver %s", VERSION);

	if ((err = usb_register(&hci_usb_driver)) < 0)
		BT_ERR("Failed to register HCI USB driver");

	return err;
}

static void __exit hci_usb_exit(void)
{
	usb_deregister(&hci_usb_driver);
}

module_init(hci_usb_init);
module_exit(hci_usb_exit);

MODULE_AUTHOR("Maxim Krasnyansky <[e-mail]>, Marcel Holtmann <[e-mail]>");
MODULE_DESCRIPTION("Bluetooth HCI USB driver ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");