[Bluetooth] Add SCO support to btusb driver

The new generic driver for Bluetooth USB devices was missing proper
SCO support. The driver now claims the second interface for these USB
devices to allow the flow of SCO packets. It also handles switching
of the alternate setting and re-submission of isochronous URBs.

The btusb driver is now a full replacement for hci_usb and thus the
experimental tag has been removed and this driver is promoted as
preferred one.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 95ae9ba..6a01068 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -2,7 +2,7 @@
  *
  *  Generic Bluetooth USB driver
  *
- *  Copyright (C) 2005-2007  Marcel Holtmann <marcel@holtmann.org>
+ *  Copyright (C) 2005-2008  Marcel Holtmann <marcel@holtmann.org>
  *
  *
  *  This program is free software; you can redistribute it and/or modify
@@ -41,7 +41,7 @@
 #define BT_DBG(D...)
 #endif
 
-#define VERSION "0.2"
+#define VERSION "0.3"
 
 static int ignore_dga;
 static int ignore_csr;
@@ -160,12 +160,16 @@
 	{ }	/* Terminating entry */
 };
 
+#define BTUSB_MAX_ISOC_FRAMES	10
+
 #define BTUSB_INTR_RUNNING	0
 #define BTUSB_BULK_RUNNING	1
+#define BTUSB_ISOC_RUNNING	2
 
 struct btusb_data {
 	struct hci_dev       *hdev;
 	struct usb_device    *udev;
+	struct usb_interface *isoc;
 
 	spinlock_t lock;
 
@@ -176,10 +180,15 @@
 	struct usb_anchor tx_anchor;
 	struct usb_anchor intr_anchor;
 	struct usb_anchor bulk_anchor;
+	struct usb_anchor isoc_anchor;
 
 	struct usb_endpoint_descriptor *intr_ep;
 	struct usb_endpoint_descriptor *bulk_tx_ep;
 	struct usb_endpoint_descriptor *bulk_rx_ep;
+	struct usb_endpoint_descriptor *isoc_tx_ep;
+	struct usb_endpoint_descriptor *isoc_rx_ep;
+
+	int isoc_altsetting;
 };
 
 static void btusb_intr_complete(struct urb *urb)
@@ -195,6 +204,8 @@
 		return;
 
 	if (urb->status == 0) {
+		hdev->stat.byte_rx += urb->actual_length;
+
 		if (hci_recv_fragment(hdev, HCI_EVENT_PKT,
 						urb->transfer_buffer,
 						urb->actual_length) < 0) {
@@ -216,7 +227,7 @@
 	}
 }
 
-static inline int btusb_submit_intr_urb(struct hci_dev *hdev)
+static int btusb_submit_intr_urb(struct hci_dev *hdev)
 {
 	struct btusb_data *data = hdev->driver_data;
 	struct urb *urb;
@@ -226,6 +237,9 @@
 
 	BT_DBG("%s", hdev->name);
 
+	if (!data->intr_ep)
+		return -ENODEV;
+
 	urb = usb_alloc_urb(0, GFP_ATOMIC);
 	if (!urb)
 		return -ENOMEM;
@@ -274,6 +288,8 @@
 		return;
 
 	if (urb->status == 0) {
+		hdev->stat.byte_rx += urb->actual_length;
+
 		if (hci_recv_fragment(hdev, HCI_ACLDATA_PKT,
 						urb->transfer_buffer,
 						urb->actual_length) < 0) {
@@ -295,7 +311,7 @@
 	}
 }
 
-static inline int btusb_submit_bulk_urb(struct hci_dev *hdev)
+static int btusb_submit_bulk_urb(struct hci_dev *hdev)
 {
 	struct btusb_data *data = hdev->driver_data;
 	struct urb *urb;
@@ -305,6 +321,9 @@
 
 	BT_DBG("%s", hdev->name);
 
+	if (!data->bulk_rx_ep)
+		return -ENODEV;
+
 	urb = usb_alloc_urb(0, GFP_KERNEL);
 	if (!urb)
 		return -ENOMEM;
@@ -339,6 +358,127 @@
 	return err;
 }
 
+static void btusb_isoc_complete(struct urb *urb)
+{
+	struct hci_dev *hdev = urb->context;
+	struct btusb_data *data = hdev->driver_data;
+	int i, 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) {
+		for (i = 0; i < urb->number_of_packets; i++) {
+			unsigned int offset = urb->iso_frame_desc[i].offset;
+			unsigned int length = urb->iso_frame_desc[i].actual_length;
+
+			if (urb->iso_frame_desc[i].status)
+				continue;
+
+			hdev->stat.byte_rx += length;
+
+			if (hci_recv_fragment(hdev, HCI_SCODATA_PKT,
+						urb->transfer_buffer + offset,
+								length) < 0) {
+				BT_ERR("%s corrupted SCO packet", hdev->name);
+				hdev->stat.err_rx++;
+			}
+		}
+	}
+
+	if (!test_bit(BTUSB_ISOC_RUNNING, &data->flags))
+		return;
+
+	usb_anchor_urb(urb, &data->isoc_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 void inline __fill_isoc_descriptor(struct urb *urb, int len, int mtu)
+{
+	int i, offset = 0;
+
+	BT_DBG("len %d mtu %d", len, mtu);
+
+	for (i = 0; i < BTUSB_MAX_ISOC_FRAMES && len >= mtu;
+					i++, offset += mtu, len -= mtu) {
+		urb->iso_frame_desc[i].offset = offset;
+		urb->iso_frame_desc[i].length = mtu;
+	}
+
+	if (len && i < BTUSB_MAX_ISOC_FRAMES) {
+		urb->iso_frame_desc[i].offset = offset;
+		urb->iso_frame_desc[i].length = len;
+		i++;
+	}
+
+	urb->number_of_packets = i;
+}
+
+static int btusb_submit_isoc_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);
+
+	if (!data->isoc_rx_ep)
+		return -ENODEV;
+
+	urb = usb_alloc_urb(BTUSB_MAX_ISOC_FRAMES, GFP_KERNEL);
+	if (!urb)
+		return -ENOMEM;
+
+	size = le16_to_cpu(data->isoc_rx_ep->wMaxPacketSize) *
+						BTUSB_MAX_ISOC_FRAMES;
+
+	buf = kmalloc(size, GFP_KERNEL);
+	if (!buf) {
+		usb_free_urb(urb);
+		return -ENOMEM;
+	}
+
+	pipe = usb_rcvisocpipe(data->udev, data->isoc_rx_ep->bEndpointAddress);
+
+	urb->dev      = data->udev;
+	urb->pipe     = pipe;
+	urb->context  = hdev;
+	urb->complete = btusb_isoc_complete;
+	urb->interval = data->isoc_rx_ep->bInterval;
+
+	urb->transfer_flags  = URB_FREE_BUFFER | URB_ISO_ASAP;
+	urb->transfer_buffer = buf;
+	urb->transfer_buffer_length = size;
+
+	__fill_isoc_descriptor(urb, size,
+			le16_to_cpu(data->isoc_rx_ep->wMaxPacketSize));
+
+	usb_anchor_urb(urb, &data->isoc_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;
@@ -392,6 +532,9 @@
 	if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
 		return 0;
 
+	clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
+	usb_kill_anchored_urbs(&data->intr_anchor);
+
 	clear_bit(BTUSB_BULK_RUNNING, &data->flags);
 	usb_kill_anchored_urbs(&data->bulk_anchor);
 
@@ -453,6 +596,9 @@
 		break;
 
 	case HCI_ACLDATA_PKT:
+		if (!data->bulk_tx_ep || hdev->conn_hash.acl_num < 1)
+			return -ENODEV;
+
 		urb = usb_alloc_urb(0, GFP_ATOMIC);
 		if (!urb)
 			return -ENOMEM;
@@ -467,9 +613,31 @@
 		break;
 
 	case HCI_SCODATA_PKT:
+		if (!data->isoc_tx_ep || hdev->conn_hash.sco_num < 1)
+			return -ENODEV;
+
+		urb = usb_alloc_urb(BTUSB_MAX_ISOC_FRAMES, GFP_ATOMIC);
+		if (!urb)
+			return -ENOMEM;
+
+		pipe = usb_sndisocpipe(data->udev,
+					data->isoc_tx_ep->bEndpointAddress);
+
+		urb->dev      = data->udev;
+		urb->pipe     = pipe;
+		urb->context  = skb;
+		urb->complete = btusb_tx_complete;
+		urb->interval = data->isoc_tx_ep->bInterval;
+
+		urb->transfer_flags  = URB_ISO_ASAP;
+		urb->transfer_buffer = skb->data;
+		urb->transfer_buffer_length = skb->len;
+
+		__fill_isoc_descriptor(urb, skb->len,
+				le16_to_cpu(data->isoc_tx_ep->wMaxPacketSize));
+
 		hdev->stat.sco_tx++;
-		kfree_skb(skb);
-		return 0;
+		break;
 
 	default:
 		return -EILSEQ;
@@ -508,22 +676,86 @@
 		schedule_work(&data->work);
 }
 
+static int inline __set_isoc_interface(struct hci_dev *hdev, int altsetting)
+{
+	struct btusb_data *data = hdev->driver_data;
+	struct usb_interface *intf = data->isoc;
+	struct usb_endpoint_descriptor *ep_desc;
+	int i, err;
+
+	if (!data->isoc)
+		return -ENODEV;
+
+	err = usb_set_interface(data->udev, 1, altsetting);
+	if (err < 0) {
+		BT_ERR("%s setting interface failed (%d)", hdev->name, -err);
+		return err;
+	}
+
+	data->isoc_altsetting = altsetting;
+
+	data->isoc_tx_ep = NULL;
+	data->isoc_rx_ep = NULL;
+
+	for (i = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) {
+		ep_desc = &intf->cur_altsetting->endpoint[i].desc;
+
+		if (!data->isoc_tx_ep && usb_endpoint_is_isoc_out(ep_desc)) {
+			data->isoc_tx_ep = ep_desc;
+			continue;
+		}
+
+		if (!data->isoc_rx_ep && usb_endpoint_is_isoc_in(ep_desc)) {
+			data->isoc_rx_ep = ep_desc;
+			continue;
+		}
+	}
+
+	if (!data->isoc_tx_ep || !data->isoc_rx_ep) {
+		BT_ERR("%s invalid SCO descriptors", hdev->name);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
 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) {
+	if (hdev->conn_hash.acl_num > 0) {
+		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);
+		}
+	} else {
 		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);
+	if (hdev->conn_hash.sco_num > 0) {
+		if (data->isoc_altsetting != 2) {
+			clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
+			usb_kill_anchored_urbs(&data->isoc_anchor);
+
+			if (__set_isoc_interface(hdev, 2) < 0)
+				return;
+		}
+
+		if (!test_and_set_bit(BTUSB_ISOC_RUNNING, &data->flags)) {
+			if (btusb_submit_isoc_urb(hdev) < 0)
+				clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
+			else
+				btusb_submit_isoc_urb(hdev);
+		}
+	} else {
+		clear_bit(BTUSB_ISOC_RUNNING, &data->flags);
+		usb_kill_anchored_urbs(&data->isoc_anchor);
+
+		__set_isoc_interface(hdev, 0);
 	}
 }
 
@@ -597,6 +829,7 @@
 	init_usb_anchor(&data->tx_anchor);
 	init_usb_anchor(&data->intr_anchor);
 	init_usb_anchor(&data->bulk_anchor);
+	init_usb_anchor(&data->isoc_anchor);
 
 	hdev = hci_alloc_dev();
 	if (!hdev) {
@@ -620,6 +853,9 @@
 
 	hdev->owner = THIS_MODULE;
 
+	/* interface numbers are hardcoded in the spec */
+	data->isoc = usb_ifnum_to_if(data->udev, 1);
+
 	if (reset || id->driver_info & BTUSB_RESET)
 		set_bit(HCI_QUIRK_RESET_ON_INIT, &hdev->quirks);
 
@@ -628,11 +864,16 @@
 			set_bit(HCI_QUIRK_FIXUP_BUFFER_SIZE, &hdev->quirks);
 	}
 
+	if (id->driver_info & BTUSB_BROKEN_ISOC)
+		data->isoc = NULL;
+
 	if (id->driver_info & BTUSB_SNIFFER) {
-		struct usb_device *udev = interface_to_usbdev(intf);
+		struct usb_device *udev = data->udev;
 
 		if (le16_to_cpu(udev->descriptor.bcdDevice) > 0x997)
 			set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
+
+		data->isoc = NULL;
 	}
 
 	if (id->driver_info & BTUSB_BCM92035) {
@@ -646,6 +887,16 @@
 		}
 	}
 
+	if (data->isoc) {
+		err = usb_driver_claim_interface(&btusb_driver,
+							data->isoc, NULL);
+		if (err < 0) {
+			hci_free_dev(hdev);
+			kfree(data);
+			return err;
+		}
+	}
+
 	err = hci_register_dev(hdev);
 	if (err < 0) {
 		hci_free_dev(hdev);
@@ -670,6 +921,9 @@
 
 	hdev = data->hdev;
 
+	if (data->isoc)
+		usb_driver_release_interface(&btusb_driver, data->isoc);
+
 	usb_set_intfdata(intf, NULL);
 
 	hci_unregister_dev(hdev);