[Bluetooth] Add generic driver for Bluetooth USB devices

This patch adds a new generic driver for Bluetooth USB devices. This
driver is still experimental at this point, but it is cleaner and
easier to maintain than the current Bluetooth USB driver. It is a
much better starting point for power management improvements.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
new file mode 100644
index 0000000..12e1089
--- /dev/null
+++ b/drivers/bluetooth/btusb.c
@@ -0,0 +1,564 @@
+/*
+ *
+ *  Generic Bluetooth USB driver
+ *
+ *  Copyright (C) 2005-2007  Marcel Holtmann <marcel@holtmann.org>
+ *
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+
+#include <linux/usb.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+//#define CONFIG_BT_HCIBTUSB_DEBUG
+#ifndef CONFIG_BT_HCIBTUSB_DEBUG
+#undef  BT_DBG
+#define BT_DBG(D...)
+#endif
+
+#define VERSION "0.1"
+
+static struct usb_device_id btusb_table[] = {
+	/* Generic Bluetooth USB device */
+	{ USB_DEVICE_INFO(0xe0, 0x01, 0x01) },
+
+	{ }	/* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE(usb, btusb_table);
+
+static struct usb_device_id blacklist_table[] = {
+	{ }	/* Terminating entry */
+};
+
+#define BTUSB_INTR_RUNNING	0
+#define BTUSB_BULK_RUNNING	1
+
+struct btusb_data {
+	struct hci_dev       *hdev;
+	struct usb_device    *udev;
+
+	spinlock_t lock;
+
+	unsigned long flags;
+
+	struct work_struct work;
+
+	struct usb_anchor tx_anchor;
+	struct usb_anchor intr_anchor;
+	struct usb_anchor bulk_anchor;
+
+	struct usb_endpoint_descriptor *intr_ep;
+	struct usb_endpoint_descriptor *bulk_tx_ep;
+	struct usb_endpoint_descriptor *bulk_rx_ep;
+};
+
+static void btusb_intr_complete(struct urb *urb)
+{
+	struct hci_dev *hdev = urb->context;
+	struct btusb_data *data = hdev->driver_data;
+	int err;
+
+	BT_DBG("%s urb %p status %d count %d", hdev->name,
+					urb, urb->status, urb->actual_length);
+
+	if (!test_bit(HCI_RUNNING, &hdev->flags))
+		return;
+
+	if (urb->status == 0) {
+		if (hci_recv_fragment(hdev, HCI_EVENT_PKT,
+						urb->transfer_buffer,
+						urb->actual_length) < 0) {
+			BT_ERR("%s corrupted event packet", hdev->name);
+			hdev->stat.err_rx++;
+		}
+	}
+
+	if (!test_bit(BTUSB_INTR_RUNNING, &data->flags))
+		return;
+
+	usb_anchor_urb(urb, &data->intr_anchor);
+
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+	if (err < 0) {
+		BT_ERR("%s urb %p failed to resubmit (%d)",
+						hdev->name, urb, -err);
+		usb_unanchor_urb(urb);
+	}
+}
+
+static inline int btusb_submit_intr_urb(struct hci_dev *hdev)
+{
+	struct btusb_data *data = hdev->driver_data;
+	struct urb *urb;
+	unsigned char *buf;
+	unsigned int pipe;
+	int err, size;
+
+	BT_DBG("%s", hdev->name);
+
+	urb = usb_alloc_urb(0, GFP_ATOMIC);
+	if (!urb)
+		return -ENOMEM;
+
+	size = le16_to_cpu(data->intr_ep->wMaxPacketSize);
+
+	buf = kmalloc(size, GFP_ATOMIC);
+	if (!buf) {
+		usb_free_urb(urb);
+		return -ENOMEM;
+	}
+
+	pipe = usb_rcvintpipe(data->udev, data->intr_ep->bEndpointAddress);
+
+	usb_fill_int_urb(urb, data->udev, pipe, buf, size,
+						btusb_intr_complete, hdev,
+						data->intr_ep->bInterval);
+
+	urb->transfer_flags |= URB_FREE_BUFFER;
+
+	usb_anchor_urb(urb, &data->intr_anchor);
+
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+	if (err < 0) {
+		BT_ERR("%s urb %p submission failed (%d)",
+						hdev->name, urb, -err);
+		usb_unanchor_urb(urb);
+		kfree(buf);
+	}
+
+	usb_free_urb(urb);
+
+	return err;
+}
+
+static void btusb_bulk_complete(struct urb *urb)
+{
+	struct hci_dev *hdev = urb->context;
+	struct btusb_data *data = hdev->driver_data;
+	int err;
+
+	BT_DBG("%s urb %p status %d count %d", hdev->name,
+					urb, urb->status, urb->actual_length);
+
+	if (!test_bit(HCI_RUNNING, &hdev->flags))
+		return;
+
+	if (urb->status == 0) {
+		if (hci_recv_fragment(hdev, HCI_ACLDATA_PKT,
+						urb->transfer_buffer,
+						urb->actual_length) < 0) {
+			BT_ERR("%s corrupted ACL packet", hdev->name);
+			hdev->stat.err_rx++;
+		}
+	}
+
+	if (!test_bit(BTUSB_BULK_RUNNING, &data->flags))
+		return;
+
+	usb_anchor_urb(urb, &data->bulk_anchor);
+
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+	if (err < 0) {
+		BT_ERR("%s urb %p failed to resubmit (%d)",
+						hdev->name, urb, -err);
+		usb_unanchor_urb(urb);
+	}
+}
+
+static inline int btusb_submit_bulk_urb(struct hci_dev *hdev)
+{
+	struct btusb_data *data = hdev->driver_data;
+	struct urb *urb;
+	unsigned char *buf;
+	unsigned int pipe;
+	int err, size;
+
+	BT_DBG("%s", hdev->name);
+
+	urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!urb)
+		return -ENOMEM;
+
+	size = le16_to_cpu(data->bulk_rx_ep->wMaxPacketSize);
+
+	buf = kmalloc(size, GFP_KERNEL);
+	if (!buf) {
+		usb_free_urb(urb);
+		return -ENOMEM;
+	}
+
+	pipe = usb_rcvbulkpipe(data->udev, data->bulk_rx_ep->bEndpointAddress);
+
+	usb_fill_bulk_urb(urb, data->udev, pipe,
+					buf, size, btusb_bulk_complete, hdev);
+
+	urb->transfer_flags |= URB_FREE_BUFFER;
+
+	usb_anchor_urb(urb, &data->bulk_anchor);
+
+	err = usb_submit_urb(urb, GFP_KERNEL);
+	if (err < 0) {
+		BT_ERR("%s urb %p submission failed (%d)",
+						hdev->name, urb, -err);
+		usb_unanchor_urb(urb);
+		kfree(buf);
+	}
+
+	usb_free_urb(urb);
+
+	return err;
+}
+
+static void btusb_tx_complete(struct urb *urb)
+{
+	struct sk_buff *skb = urb->context;
+	struct hci_dev *hdev = (struct hci_dev *) skb->dev;
+
+	BT_DBG("%s urb %p status %d count %d", hdev->name,
+					urb, urb->status, urb->actual_length);
+
+	if (!test_bit(HCI_RUNNING, &hdev->flags))
+		goto done;
+
+	if (!urb->status)
+		hdev->stat.byte_tx += urb->transfer_buffer_length;
+	else
+		hdev->stat.err_tx++;
+
+done:
+	kfree(urb->setup_packet);
+
+	kfree_skb(skb);
+}
+
+static int btusb_open(struct hci_dev *hdev)
+{
+	struct btusb_data *data = hdev->driver_data;
+	int err;
+
+	BT_DBG("%s", hdev->name);
+
+	if (test_and_set_bit(HCI_RUNNING, &hdev->flags))
+		return 0;
+
+	if (test_and_set_bit(BTUSB_INTR_RUNNING, &data->flags))
+		return 0;
+
+	err = btusb_submit_intr_urb(hdev);
+	if (err < 0) {
+		clear_bit(BTUSB_INTR_RUNNING, &hdev->flags);
+		clear_bit(HCI_RUNNING, &hdev->flags);
+	}
+
+	return err;
+}
+
+static int btusb_close(struct hci_dev *hdev)
+{
+	struct btusb_data *data = hdev->driver_data;
+
+	BT_DBG("%s", hdev->name);
+
+	if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
+		return 0;
+
+	clear_bit(BTUSB_BULK_RUNNING, &data->flags);
+	usb_kill_anchored_urbs(&data->bulk_anchor);
+
+	clear_bit(BTUSB_INTR_RUNNING, &data->flags);
+	usb_kill_anchored_urbs(&data->intr_anchor);
+
+	return 0;
+}
+
+static int btusb_flush(struct hci_dev *hdev)
+{
+	struct btusb_data *data = hdev->driver_data;
+
+	BT_DBG("%s", hdev->name);
+
+	usb_kill_anchored_urbs(&data->tx_anchor);
+
+	return 0;
+}
+
+static int btusb_send_frame(struct sk_buff *skb)
+{
+	struct hci_dev *hdev = (struct hci_dev *) skb->dev;
+	struct btusb_data *data = hdev->driver_data;
+	struct usb_ctrlrequest *dr;
+	struct urb *urb;
+	unsigned int pipe;
+	int err;
+
+	BT_DBG("%s", hdev->name);
+
+	if (!test_bit(HCI_RUNNING, &hdev->flags))
+		return -EBUSY;
+
+	switch (bt_cb(skb)->pkt_type) {
+	case HCI_COMMAND_PKT:
+		urb = usb_alloc_urb(0, GFP_ATOMIC);
+		if (!urb)
+			return -ENOMEM;
+
+		dr = kmalloc(sizeof(*dr), GFP_ATOMIC);
+		if (!dr) {
+			usb_free_urb(urb);
+			return -ENOMEM;
+		}
+
+		dr->bRequestType = USB_TYPE_CLASS;
+		dr->bRequest     = 0;
+		dr->wIndex       = 0;
+		dr->wValue       = 0;
+		dr->wLength      = __cpu_to_le16(skb->len);
+
+		pipe = usb_sndctrlpipe(data->udev, 0x00);
+
+		usb_fill_control_urb(urb, data->udev, pipe, (void *) dr,
+				skb->data, skb->len, btusb_tx_complete, skb);
+
+		hdev->stat.cmd_tx++;
+		break;
+
+	case HCI_ACLDATA_PKT:
+		urb = usb_alloc_urb(0, GFP_ATOMIC);
+		if (!urb)
+			return -ENOMEM;
+
+		pipe = usb_sndbulkpipe(data->udev,
+					data->bulk_tx_ep->bEndpointAddress);
+
+		usb_fill_bulk_urb(urb, data->udev, pipe,
+				skb->data, skb->len, btusb_tx_complete, skb);
+
+		hdev->stat.acl_tx++;
+		break;
+
+	case HCI_SCODATA_PKT:
+		hdev->stat.sco_tx++;
+		kfree_skb(skb);
+		return 0;
+
+	default:
+		return -EILSEQ;
+	}
+
+	usb_anchor_urb(urb, &data->tx_anchor);
+
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+	if (err < 0) {
+		BT_ERR("%s urb %p submission failed", hdev->name, urb);
+		kfree(urb->setup_packet);
+		usb_unanchor_urb(urb);
+	}
+
+	usb_free_urb(urb);
+
+	return err;
+}
+
+static void btusb_destruct(struct hci_dev *hdev)
+{
+	struct btusb_data *data = hdev->driver_data;
+
+	BT_DBG("%s", hdev->name);
+
+	kfree(data);
+}
+
+static void btusb_notify(struct hci_dev *hdev, unsigned int evt)
+{
+	struct btusb_data *data = hdev->driver_data;
+
+	BT_DBG("%s evt %d", hdev->name, evt);
+
+	if (evt == HCI_NOTIFY_CONN_ADD || evt == HCI_NOTIFY_CONN_DEL)
+		schedule_work(&data->work);
+}
+
+static void btusb_work(struct work_struct *work)
+{
+	struct btusb_data *data = container_of(work, struct btusb_data, work);
+	struct hci_dev *hdev = data->hdev;
+
+	if (hdev->conn_hash.acl_num == 0) {
+		clear_bit(BTUSB_BULK_RUNNING, &data->flags);
+		usb_kill_anchored_urbs(&data->bulk_anchor);
+		return;
+	}
+
+	if (!test_and_set_bit(BTUSB_BULK_RUNNING, &data->flags)) {
+		if (btusb_submit_bulk_urb(hdev) < 0)
+			clear_bit(BTUSB_BULK_RUNNING, &data->flags);
+		else
+			btusb_submit_bulk_urb(hdev);
+	}
+}
+
+static int btusb_probe(struct usb_interface *intf,
+				const struct usb_device_id *id)
+{
+	struct usb_endpoint_descriptor *ep_desc;
+	struct btusb_data *data;
+	struct hci_dev *hdev;
+	int i, err;
+
+	BT_DBG("intf %p id %p", intf, id);
+
+	if (intf->cur_altsetting->desc.bInterfaceNumber != 0)
+		return -ENODEV;
+
+	if (!id->driver_info) {
+		const struct usb_device_id *match;
+		match = usb_match_id(intf, blacklist_table);
+		if (match)
+			id = match;
+	}
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	for (i = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) {
+		ep_desc = &intf->cur_altsetting->endpoint[i].desc;
+
+		if (!data->intr_ep && usb_endpoint_is_int_in(ep_desc)) {
+			data->intr_ep = ep_desc;
+			continue;
+		}
+
+		if (!data->bulk_tx_ep && usb_endpoint_is_bulk_out(ep_desc)) {
+			data->bulk_tx_ep = ep_desc;
+			continue;
+		}
+
+		if (!data->bulk_rx_ep && usb_endpoint_is_bulk_in(ep_desc)) {
+			data->bulk_rx_ep = ep_desc;
+			continue;
+		}
+	}
+
+	if (!data->intr_ep || !data->bulk_tx_ep || !data->bulk_rx_ep) {
+		kfree(data);
+		return -ENODEV;
+	}
+
+	data->udev = interface_to_usbdev(intf);
+
+	spin_lock_init(&data->lock);
+
+	INIT_WORK(&data->work, btusb_work);
+
+	init_usb_anchor(&data->tx_anchor);
+	init_usb_anchor(&data->intr_anchor);
+	init_usb_anchor(&data->bulk_anchor);
+
+	hdev = hci_alloc_dev();
+	if (!hdev) {
+		kfree(data);
+		return -ENOMEM;
+	}
+
+	hdev->type = HCI_USB;
+	hdev->driver_data = data;
+
+	data->hdev = hdev;
+
+	SET_HCIDEV_DEV(hdev, &intf->dev);
+
+	hdev->open     = btusb_open;
+	hdev->close    = btusb_close;
+	hdev->flush    = btusb_flush;
+	hdev->send     = btusb_send_frame;
+	hdev->destruct = btusb_destruct;
+	hdev->notify   = btusb_notify;
+
+	hdev->owner = THIS_MODULE;
+
+	set_bit(HCI_QUIRK_RESET_ON_INIT, &hdev->quirks);
+
+	err = hci_register_dev(hdev);
+	if (err < 0) {
+		hci_free_dev(hdev);
+		kfree(data);
+		return err;
+	}
+
+	usb_set_intfdata(intf, data);
+
+	return 0;
+}
+
+static void btusb_disconnect(struct usb_interface *intf)
+{
+	struct btusb_data *data = usb_get_intfdata(intf);
+	struct hci_dev *hdev;
+
+	BT_DBG("intf %p", intf);
+
+	if (!data)
+		return;
+
+	hdev = data->hdev;
+
+	usb_set_intfdata(intf, NULL);
+
+	hci_unregister_dev(hdev);
+
+	hci_free_dev(hdev);
+}
+
+static struct usb_driver btusb_driver = {
+	.name		= "btusb",
+	.probe		= btusb_probe,
+	.disconnect	= btusb_disconnect,
+	.id_table	= btusb_table,
+};
+
+static int __init btusb_init(void)
+{
+	BT_INFO("Generic Bluetooth USB driver ver %s", VERSION);
+
+	return usb_register(&btusb_driver);
+}
+
+static void __exit btusb_exit(void)
+{
+	usb_deregister(&btusb_driver);
+}
+
+module_init(btusb_init);
+module_exit(btusb_exit);
+
+MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
+MODULE_DESCRIPTION("Generic Bluetooth USB driver ver " VERSION);
+MODULE_VERSION(VERSION);
+MODULE_LICENSE("GPL");