Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 912 insertions, 0 deletions

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c b/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
new file mode 100644
index 000000000..8fd22c698
--- /dev/null
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
@@ -0,0 +1,912 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+	Copyright (C) 2010 Willow Garage <http://www.willowgarage.com>
+	Copyright (C) 2004 - 2010 Ivo van Doorn <IvDoorn@gmail.com>
+	<http://rt2x00.serialmonkey.com>
+
+ */
+
+/*
+	Module: rt2x00usb
+	Abstract: rt2x00 generic usb device routines.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/bug.h>
+
+#include "rt2x00.h"
+#include "rt2x00usb.h"
+
+static bool rt2x00usb_check_usb_error(struct rt2x00_dev *rt2x00dev, int status)
+{
+	if (status == -ENODEV || status == -ENOENT)
+		return true;
+
+	if (!test_bit(DEVICE_STATE_STARTED, &rt2x00dev->flags))
+		return false;
+
+	if (status == -EPROTO || status == -ETIMEDOUT)
+		rt2x00dev->num_proto_errs++;
+	else
+		rt2x00dev->num_proto_errs = 0;
+
+	if (rt2x00dev->num_proto_errs > 3)
+		return true;
+
+	return false;
+}
+
+/*
+ * Interfacing with the HW.
+ */
+int rt2x00usb_vendor_request(struct rt2x00_dev *rt2x00dev,
+			     const u8 request, const u8 requesttype,
+			     const u16 offset, const u16 value,
+			     void *buffer, const u16 buffer_length,
+			     const int timeout)
+{
+	struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
+	int status;
+	unsigned int pipe =
+	    (requesttype == USB_VENDOR_REQUEST_IN) ?
+	    usb_rcvctrlpipe(usb_dev, 0) : usb_sndctrlpipe(usb_dev, 0);
+	unsigned long expire = jiffies + msecs_to_jiffies(timeout);
+
+	if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
+		return -ENODEV;
+
+	do {
+		status = usb_control_msg(usb_dev, pipe, request, requesttype,
+					 value, offset, buffer, buffer_length,
+					 timeout / 2);
+		if (status >= 0)
+			return 0;
+
+		if (rt2x00usb_check_usb_error(rt2x00dev, status)) {
+			/* Device has disappeared. */
+			clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
+			break;
+		}
+	} while (time_before(jiffies, expire));
+
+	rt2x00_err(rt2x00dev,
+		   "Vendor Request 0x%02x failed for offset 0x%04x with error %d\n",
+		   request, offset, status);
+
+	return status;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request);
+
+int rt2x00usb_vendor_req_buff_lock(struct rt2x00_dev *rt2x00dev,
+				   const u8 request, const u8 requesttype,
+				   const u16 offset, void *buffer,
+				   const u16 buffer_length, const int timeout)
+{
+	int status;
+
+	BUG_ON(!mutex_is_locked(&rt2x00dev->csr_mutex));
+
+	/*
+	 * Check for Cache availability.
+	 */
+	if (unlikely(!rt2x00dev->csr.cache || buffer_length > CSR_CACHE_SIZE)) {
+		rt2x00_err(rt2x00dev, "CSR cache not available\n");
+		return -ENOMEM;
+	}
+
+	if (requesttype == USB_VENDOR_REQUEST_OUT)
+		memcpy(rt2x00dev->csr.cache, buffer, buffer_length);
+
+	status = rt2x00usb_vendor_request(rt2x00dev, request, requesttype,
+					  offset, 0, rt2x00dev->csr.cache,
+					  buffer_length, timeout);
+
+	if (!status && requesttype == USB_VENDOR_REQUEST_IN)
+		memcpy(buffer, rt2x00dev->csr.cache, buffer_length);
+
+	return status;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_vendor_req_buff_lock);
+
+int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
+				  const u8 request, const u8 requesttype,
+				  const u16 offset, void *buffer,
+				  const u16 buffer_length)
+{
+	int status = 0;
+	u8 *tb;
+	u16 off, len, bsize;
+
+	mutex_lock(&rt2x00dev->csr_mutex);
+
+	tb  = (u8 *)buffer;
+	off = offset;
+	len = buffer_length;
+	while (len && !status) {
+		bsize = min_t(u16, CSR_CACHE_SIZE, len);
+		status = rt2x00usb_vendor_req_buff_lock(rt2x00dev, request,
+							requesttype, off, tb,
+							bsize, REGISTER_TIMEOUT);
+
+		tb  += bsize;
+		len -= bsize;
+		off += bsize;
+	}
+
+	mutex_unlock(&rt2x00dev->csr_mutex);
+
+	return status;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request_buff);
+
+int rt2x00usb_regbusy_read(struct rt2x00_dev *rt2x00dev,
+			   const unsigned int offset,
+			   const struct rt2x00_field32 field,
+			   u32 *reg)
+{
+	unsigned int i;
+
+	if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
+		return -ENODEV;
+
+	for (i = 0; i < REGISTER_USB_BUSY_COUNT; i++) {
+		*reg = rt2x00usb_register_read_lock(rt2x00dev, offset);
+		if (!rt2x00_get_field32(*reg, field))
+			return 1;
+		udelay(REGISTER_BUSY_DELAY);
+	}
+
+	rt2x00_err(rt2x00dev, "Indirect register access failed: offset=0x%.08x, value=0x%.08x\n",
+		   offset, *reg);
+	*reg = ~0;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_regbusy_read);
+
+
+struct rt2x00_async_read_data {
+	__le32 reg;
+	struct usb_ctrlrequest cr;
+	struct rt2x00_dev *rt2x00dev;
+	bool (*callback)(struct rt2x00_dev *, int, u32);
+};
+
+static void rt2x00usb_register_read_async_cb(struct urb *urb)
+{
+	struct rt2x00_async_read_data *rd = urb->context;
+	if (rd->callback(rd->rt2x00dev, urb->status, le32_to_cpu(rd->reg))) {
+		usb_anchor_urb(urb, rd->rt2x00dev->anchor);
+		if (usb_submit_urb(urb, GFP_ATOMIC) < 0) {
+			usb_unanchor_urb(urb);
+			kfree(rd);
+		}
+	} else
+		kfree(rd);
+}
+
+void rt2x00usb_register_read_async(struct rt2x00_dev *rt2x00dev,
+				   const unsigned int offset,
+				   bool (*callback)(struct rt2x00_dev*, int, u32))
+{
+	struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
+	struct urb *urb;
+	struct rt2x00_async_read_data *rd;
+
+	rd = kmalloc(sizeof(*rd), GFP_ATOMIC);
+	if (!rd)
+		return;
+
+	urb = usb_alloc_urb(0, GFP_ATOMIC);
+	if (!urb) {
+		kfree(rd);
+		return;
+	}
+
+	rd->rt2x00dev = rt2x00dev;
+	rd->callback = callback;
+	rd->cr.bRequestType = USB_VENDOR_REQUEST_IN;
+	rd->cr.bRequest = USB_MULTI_READ;
+	rd->cr.wValue = 0;
+	rd->cr.wIndex = cpu_to_le16(offset);
+	rd->cr.wLength = cpu_to_le16(sizeof(u32));
+
+	usb_fill_control_urb(urb, usb_dev, usb_rcvctrlpipe(usb_dev, 0),
+			     (u8 *)(&rd->cr), &rd->reg, sizeof(rd->reg),
+			     rt2x00usb_register_read_async_cb, rd);
+	usb_anchor_urb(urb, rt2x00dev->anchor);
+	if (usb_submit_urb(urb, GFP_ATOMIC) < 0) {
+		usb_unanchor_urb(urb);
+		kfree(rd);
+	}
+	usb_free_urb(urb);
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_register_read_async);
+
+/*
+ * TX data handlers.
+ */
+static void rt2x00usb_work_txdone_entry(struct queue_entry *entry)
+{
+	/*
+	 * If the transfer to hardware succeeded, it does not mean the
+	 * frame was send out correctly. It only means the frame
+	 * was successfully pushed to the hardware, we have no
+	 * way to determine the transmission status right now.
+	 * (Only indirectly by looking at the failed TX counters
+	 * in the register).
+	 */
+	if (test_bit(ENTRY_DATA_IO_FAILED, &entry->flags))
+		rt2x00lib_txdone_noinfo(entry, TXDONE_FAILURE);
+	else
+		rt2x00lib_txdone_noinfo(entry, TXDONE_UNKNOWN);
+}
+
+static void rt2x00usb_work_txdone(struct work_struct *work)
+{
+	struct rt2x00_dev *rt2x00dev =
+	    container_of(work, struct rt2x00_dev, txdone_work);
+	struct data_queue *queue;
+	struct queue_entry *entry;
+
+	tx_queue_for_each(rt2x00dev, queue) {
+		while (!rt2x00queue_empty(queue)) {
+			entry = rt2x00queue_get_entry(queue, Q_INDEX_DONE);
+
+			if (test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags) ||
+			    !test_bit(ENTRY_DATA_STATUS_PENDING, &entry->flags))
+				break;
+
+			rt2x00usb_work_txdone_entry(entry);
+		}
+	}
+}
+
+static void rt2x00usb_interrupt_txdone(struct urb *urb)
+{
+	struct queue_entry *entry = (struct queue_entry *)urb->context;
+	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
+
+	if (!test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
+		return;
+	/*
+	 * Check if the frame was correctly uploaded
+	 */
+	if (urb->status)
+		set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
+	/*
+	 * Report the frame as DMA done
+	 */
+	rt2x00lib_dmadone(entry);
+
+	if (rt2x00dev->ops->lib->tx_dma_done)
+		rt2x00dev->ops->lib->tx_dma_done(entry);
+	/*
+	 * Schedule the delayed work for reading the TX status
+	 * from the device.
+	 */
+	if (!rt2x00_has_cap_flag(rt2x00dev, REQUIRE_TXSTATUS_FIFO) ||
+	    !kfifo_is_empty(&rt2x00dev->txstatus_fifo))
+		queue_work(rt2x00dev->workqueue, &rt2x00dev->txdone_work);
+}
+
+static bool rt2x00usb_kick_tx_entry(struct queue_entry *entry, void *data)
+{
+	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
+	struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
+	struct queue_entry_priv_usb *entry_priv = entry->priv_data;
+	u32 length;
+	int status;
+
+	if (!test_and_clear_bit(ENTRY_DATA_PENDING, &entry->flags) ||
+	    test_bit(ENTRY_DATA_STATUS_PENDING, &entry->flags))
+		return false;
+
+	/*
+	 * USB devices require certain padding at the end of each frame
+	 * and urb. Those paddings are not included in skbs. Pass entry
+	 * to the driver to determine what the overall length should be.
+	 */
+	length = rt2x00dev->ops->lib->get_tx_data_len(entry);
+
+	status = skb_padto(entry->skb, length);
+	if (unlikely(status)) {
+		/* TODO: report something more appropriate than IO_FAILED. */
+		rt2x00_warn(rt2x00dev, "TX SKB padding error, out of memory\n");
+		set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
+		rt2x00lib_dmadone(entry);
+
+		return false;
+	}
+
+	usb_fill_bulk_urb(entry_priv->urb, usb_dev,
+			  usb_sndbulkpipe(usb_dev, entry->queue->usb_endpoint),
+			  entry->skb->data, length,
+			  rt2x00usb_interrupt_txdone, entry);
+
+	status = usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
+	if (status) {
+		if (rt2x00usb_check_usb_error(rt2x00dev, status))
+			clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
+		set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
+		rt2x00lib_dmadone(entry);
+	}
+
+	return false;
+}
+
+/*
+ * RX data handlers.
+ */
+static void rt2x00usb_work_rxdone(struct work_struct *work)
+{
+	struct rt2x00_dev *rt2x00dev =
+	    container_of(work, struct rt2x00_dev, rxdone_work);
+	struct queue_entry *entry;
+	struct skb_frame_desc *skbdesc;
+	u8 rxd[32];
+
+	while (!rt2x00queue_empty(rt2x00dev->rx)) {
+		entry = rt2x00queue_get_entry(rt2x00dev->rx, Q_INDEX_DONE);
+
+		if (test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
+			break;
+
+		/*
+		 * Fill in desc fields of the skb descriptor
+		 */
+		skbdesc = get_skb_frame_desc(entry->skb);
+		skbdesc->desc = rxd;
+		skbdesc->desc_len = entry->queue->desc_size;
+
+		/*
+		 * Send the frame to rt2x00lib for further processing.
+		 */
+		rt2x00lib_rxdone(entry, GFP_KERNEL);
+	}
+}
+
+static void rt2x00usb_interrupt_rxdone(struct urb *urb)
+{
+	struct queue_entry *entry = (struct queue_entry *)urb->context;
+	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
+
+	if (!test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
+		return;
+
+	/*
+	 * Check if the received data is simply too small
+	 * to be actually valid, or if the urb is signaling
+	 * a problem.
+	 */
+	if (urb->actual_length < entry->queue->desc_size || urb->status)
+		set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
+
+	/*
+	 * Report the frame as DMA done
+	 */
+	rt2x00lib_dmadone(entry);
+
+	/*
+	 * Schedule the delayed work for processing RX data
+	 */
+	queue_work(rt2x00dev->workqueue, &rt2x00dev->rxdone_work);
+}
+
+static bool rt2x00usb_kick_rx_entry(struct queue_entry *entry, void *data)
+{
+	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
+	struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
+	struct queue_entry_priv_usb *entry_priv = entry->priv_data;
+	int status;
+
+	if (test_and_set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
+		return false;
+
+	rt2x00lib_dmastart(entry);
+
+	usb_fill_bulk_urb(entry_priv->urb, usb_dev,
+			  usb_rcvbulkpipe(usb_dev, entry->queue->usb_endpoint),
+			  entry->skb->data, entry->skb->len,
+			  rt2x00usb_interrupt_rxdone, entry);
+
+	status = usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
+	if (status) {
+		if (rt2x00usb_check_usb_error(rt2x00dev, status))
+			clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
+		set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
+		rt2x00lib_dmadone(entry);
+	}
+
+	return false;
+}
+
+void rt2x00usb_kick_queue(struct data_queue *queue)
+{
+	switch (queue->qid) {
+	case QID_AC_VO:
+	case QID_AC_VI:
+	case QID_AC_BE:
+	case QID_AC_BK:
+		if (!rt2x00queue_empty(queue))
+			rt2x00queue_for_each_entry(queue,
+						   Q_INDEX_DONE,
+						   Q_INDEX,
+						   NULL,
+						   rt2x00usb_kick_tx_entry);
+		break;
+	case QID_RX:
+		if (!rt2x00queue_full(queue))
+			rt2x00queue_for_each_entry(queue,
+						   Q_INDEX,
+						   Q_INDEX_DONE,
+						   NULL,
+						   rt2x00usb_kick_rx_entry);
+		break;
+	default:
+		break;
+	}
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_kick_queue);
+
+static bool rt2x00usb_flush_entry(struct queue_entry *entry, void *data)
+{
+	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
+	struct queue_entry_priv_usb *entry_priv = entry->priv_data;
+	struct queue_entry_priv_usb_bcn *bcn_priv = entry->priv_data;
+
+	if (!test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
+		return false;
+
+	usb_kill_urb(entry_priv->urb);
+
+	/*
+	 * Kill guardian urb (if required by driver).
+	 */
+	if ((entry->queue->qid == QID_BEACON) &&
+	    (rt2x00_has_cap_flag(rt2x00dev, REQUIRE_BEACON_GUARD)))
+		usb_kill_urb(bcn_priv->guardian_urb);
+
+	return false;
+}
+
+void rt2x00usb_flush_queue(struct data_queue *queue, bool drop)
+{
+	struct work_struct *completion;
+	unsigned int i;
+
+	if (drop)
+		rt2x00queue_for_each_entry(queue, Q_INDEX_DONE, Q_INDEX, NULL,
+					   rt2x00usb_flush_entry);
+
+	/*
+	 * Obtain the queue completion handler
+	 */
+	switch (queue->qid) {
+	case QID_AC_VO:
+	case QID_AC_VI:
+	case QID_AC_BE:
+	case QID_AC_BK:
+		completion = &queue->rt2x00dev->txdone_work;
+		break;
+	case QID_RX:
+		completion = &queue->rt2x00dev->rxdone_work;
+		break;
+	default:
+		return;
+	}
+
+	for (i = 0; i < 10; i++) {
+		/*
+		 * Check if the driver is already done, otherwise we
+		 * have to sleep a little while to give the driver/hw
+		 * the oppurtunity to complete interrupt process itself.
+		 */
+		if (rt2x00queue_empty(queue))
+			break;
+
+		/*
+		 * Schedule the completion handler manually, when this
+		 * worker function runs, it should cleanup the queue.
+		 */
+		queue_work(queue->rt2x00dev->workqueue, completion);
+
+		/*
+		 * Wait for a little while to give the driver
+		 * the oppurtunity to recover itself.
+		 */
+		msleep(50);
+	}
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_flush_queue);
+
+static void rt2x00usb_watchdog_tx_dma(struct data_queue *queue)
+{
+	rt2x00_warn(queue->rt2x00dev, "TX queue %d DMA timed out, invoke forced reset\n",
+		    queue->qid);
+
+	rt2x00queue_stop_queue(queue);
+	rt2x00queue_flush_queue(queue, true);
+	rt2x00queue_start_queue(queue);
+}
+
+static int rt2x00usb_dma_timeout(struct data_queue *queue)
+{
+	struct queue_entry *entry;
+
+	entry = rt2x00queue_get_entry(queue, Q_INDEX_DMA_DONE);
+	return rt2x00queue_dma_timeout(entry);
+}
+
+void rt2x00usb_watchdog(struct rt2x00_dev *rt2x00dev)
+{
+	struct data_queue *queue;
+
+	tx_queue_for_each(rt2x00dev, queue) {
+		if (!rt2x00queue_empty(queue)) {
+			if (rt2x00usb_dma_timeout(queue))
+				rt2x00usb_watchdog_tx_dma(queue);
+		}
+	}
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_watchdog);
+
+/*
+ * Radio handlers
+ */
+void rt2x00usb_disable_radio(struct rt2x00_dev *rt2x00dev)
+{
+	rt2x00usb_vendor_request_sw(rt2x00dev, USB_RX_CONTROL, 0, 0,
+				    REGISTER_TIMEOUT);
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_disable_radio);
+
+/*
+ * Device initialization handlers.
+ */
+void rt2x00usb_clear_entry(struct queue_entry *entry)
+{
+	entry->flags = 0;
+
+	if (entry->queue->qid == QID_RX)
+		rt2x00usb_kick_rx_entry(entry, NULL);
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_clear_entry);
+
+static void rt2x00usb_assign_endpoint(struct data_queue *queue,
+				      struct usb_endpoint_descriptor *ep_desc)
+{
+	struct usb_device *usb_dev = to_usb_device_intf(queue->rt2x00dev->dev);
+	int pipe;
+
+	queue->usb_endpoint = usb_endpoint_num(ep_desc);
+
+	if (queue->qid == QID_RX) {
+		pipe = usb_rcvbulkpipe(usb_dev, queue->usb_endpoint);
+		queue->usb_maxpacket = usb_maxpacket(usb_dev, pipe);
+	} else {
+		pipe = usb_sndbulkpipe(usb_dev, queue->usb_endpoint);
+		queue->usb_maxpacket = usb_maxpacket(usb_dev, pipe);
+	}
+
+	if (!queue->usb_maxpacket)
+		queue->usb_maxpacket = 1;
+}
+
+static int rt2x00usb_find_endpoints(struct rt2x00_dev *rt2x00dev)
+{
+	struct usb_interface *intf = to_usb_interface(rt2x00dev->dev);
+	struct usb_host_interface *intf_desc = intf->cur_altsetting;
+	struct usb_endpoint_descriptor *ep_desc;
+	struct data_queue *queue = rt2x00dev->tx;
+	struct usb_endpoint_descriptor *tx_ep_desc = NULL;
+	unsigned int i;
+
+	/*
+	 * Walk through all available endpoints to search for "bulk in"
+	 * and "bulk out" endpoints. When we find such endpoints collect
+	 * the information we need from the descriptor and assign it
+	 * to the queue.
+	 */
+	for (i = 0; i < intf_desc->desc.bNumEndpoints; i++) {
+		ep_desc = &intf_desc->endpoint[i].desc;
+
+		if (usb_endpoint_is_bulk_in(ep_desc)) {
+			rt2x00usb_assign_endpoint(rt2x00dev->rx, ep_desc);
+		} else if (usb_endpoint_is_bulk_out(ep_desc) &&
+			   (queue != queue_end(rt2x00dev))) {
+			rt2x00usb_assign_endpoint(queue, ep_desc);
+			queue = queue_next(queue);
+
+			tx_ep_desc = ep_desc;
+		}
+	}
+
+	/*
+	 * At least 1 endpoint for RX and 1 endpoint for TX must be available.
+	 */
+	if (!rt2x00dev->rx->usb_endpoint || !rt2x00dev->tx->usb_endpoint) {
+		rt2x00_err(rt2x00dev, "Bulk-in/Bulk-out endpoints not found\n");
+		return -EPIPE;
+	}
+
+	/*
+	 * It might be possible not all queues have a dedicated endpoint.
+	 * Loop through all TX queues and copy the endpoint information
+	 * which we have gathered from already assigned endpoints.
+	 */
+	txall_queue_for_each(rt2x00dev, queue) {
+		if (!queue->usb_endpoint)
+			rt2x00usb_assign_endpoint(queue, tx_ep_desc);
+	}
+
+	return 0;
+}
+
+static int rt2x00usb_alloc_entries(struct data_queue *queue)
+{
+	struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
+	struct queue_entry_priv_usb *entry_priv;
+	struct queue_entry_priv_usb_bcn *bcn_priv;
+	unsigned int i;
+
+	for (i = 0; i < queue->limit; i++) {
+		entry_priv = queue->entries[i].priv_data;
+		entry_priv->urb = usb_alloc_urb(0, GFP_KERNEL);
+		if (!entry_priv->urb)
+			return -ENOMEM;
+	}
+
+	/*
+	 * If this is not the beacon queue or
+	 * no guardian byte was required for the beacon,
+	 * then we are done.
+	 */
+	if (queue->qid != QID_BEACON ||
+	    !rt2x00_has_cap_flag(rt2x00dev, REQUIRE_BEACON_GUARD))
+		return 0;
+
+	for (i = 0; i < queue->limit; i++) {
+		bcn_priv = queue->entries[i].priv_data;
+		bcn_priv->guardian_urb = usb_alloc_urb(0, GFP_KERNEL);
+		if (!bcn_priv->guardian_urb)
+			return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void rt2x00usb_free_entries(struct data_queue *queue)
+{
+	struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
+	struct queue_entry_priv_usb *entry_priv;
+	struct queue_entry_priv_usb_bcn *bcn_priv;
+	unsigned int i;
+
+	if (!queue->entries)
+		return;
+
+	for (i = 0; i < queue->limit; i++) {
+		entry_priv = queue->entries[i].priv_data;
+		usb_kill_urb(entry_priv->urb);
+		usb_free_urb(entry_priv->urb);
+	}
+
+	/*
+	 * If this is not the beacon queue or
+	 * no guardian byte was required for the beacon,
+	 * then we are done.
+	 */
+	if (queue->qid != QID_BEACON ||
+	    !rt2x00_has_cap_flag(rt2x00dev, REQUIRE_BEACON_GUARD))
+		return;
+
+	for (i = 0; i < queue->limit; i++) {
+		bcn_priv = queue->entries[i].priv_data;
+		usb_kill_urb(bcn_priv->guardian_urb);
+		usb_free_urb(bcn_priv->guardian_urb);
+	}
+}
+
+int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
+{
+	struct data_queue *queue;
+	int status;
+
+	/*
+	 * Find endpoints for each queue
+	 */
+	status = rt2x00usb_find_endpoints(rt2x00dev);
+	if (status)
+		goto exit;
+
+	/*
+	 * Allocate DMA
+	 */
+	queue_for_each(rt2x00dev, queue) {
+		status = rt2x00usb_alloc_entries(queue);
+		if (status)
+			goto exit;
+	}
+
+	return 0;
+
+exit:
+	rt2x00usb_uninitialize(rt2x00dev);
+
+	return status;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_initialize);
+
+void rt2x00usb_uninitialize(struct rt2x00_dev *rt2x00dev)
+{
+	struct data_queue *queue;
+
+	usb_kill_anchored_urbs(rt2x00dev->anchor);
+	hrtimer_cancel(&rt2x00dev->txstatus_timer);
+	cancel_work_sync(&rt2x00dev->rxdone_work);
+	cancel_work_sync(&rt2x00dev->txdone_work);
+
+	queue_for_each(rt2x00dev, queue)
+		rt2x00usb_free_entries(queue);
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_uninitialize);
+
+/*
+ * USB driver handlers.
+ */
+static void rt2x00usb_free_reg(struct rt2x00_dev *rt2x00dev)
+{
+	kfree(rt2x00dev->rf);
+	rt2x00dev->rf = NULL;
+
+	kfree(rt2x00dev->eeprom);
+	rt2x00dev->eeprom = NULL;
+
+	kfree(rt2x00dev->csr.cache);
+	rt2x00dev->csr.cache = NULL;
+}
+
+static int rt2x00usb_alloc_reg(struct rt2x00_dev *rt2x00dev)
+{
+	rt2x00dev->csr.cache = kzalloc(CSR_CACHE_SIZE, GFP_KERNEL);
+	if (!rt2x00dev->csr.cache)
+		goto exit;
+
+	rt2x00dev->eeprom = kzalloc(rt2x00dev->ops->eeprom_size, GFP_KERNEL);
+	if (!rt2x00dev->eeprom)
+		goto exit;
+
+	rt2x00dev->rf = kzalloc(rt2x00dev->ops->rf_size, GFP_KERNEL);
+	if (!rt2x00dev->rf)
+		goto exit;
+
+	return 0;
+
+exit:
+	rt2x00_probe_err("Failed to allocate registers\n");
+
+	rt2x00usb_free_reg(rt2x00dev);
+
+	return -ENOMEM;
+}
+
+int rt2x00usb_probe(struct usb_interface *usb_intf,
+		    const struct rt2x00_ops *ops)
+{
+	struct usb_device *usb_dev = interface_to_usbdev(usb_intf);
+	struct ieee80211_hw *hw;
+	struct rt2x00_dev *rt2x00dev;
+	int retval;
+
+	usb_dev = usb_get_dev(usb_dev);
+	usb_reset_device(usb_dev);
+
+	hw = ieee80211_alloc_hw(sizeof(struct rt2x00_dev), ops->hw);
+	if (!hw) {
+		rt2x00_probe_err("Failed to allocate hardware\n");
+		retval = -ENOMEM;
+		goto exit_put_device;
+	}
+
+	usb_set_intfdata(usb_intf, hw);
+
+	rt2x00dev = hw->priv;
+	rt2x00dev->dev = &usb_intf->dev;
+	rt2x00dev->ops = ops;
+	rt2x00dev->hw = hw;
+
+	rt2x00_set_chip_intf(rt2x00dev, RT2X00_CHIP_INTF_USB);
+
+	INIT_WORK(&rt2x00dev->rxdone_work, rt2x00usb_work_rxdone);
+	INIT_WORK(&rt2x00dev->txdone_work, rt2x00usb_work_txdone);
+	hrtimer_init(&rt2x00dev->txstatus_timer, CLOCK_MONOTONIC,
+		     HRTIMER_MODE_REL);
+
+	retval = rt2x00usb_alloc_reg(rt2x00dev);
+	if (retval)
+		goto exit_free_device;
+
+	rt2x00dev->anchor = devm_kmalloc(&usb_dev->dev,
+					sizeof(struct usb_anchor),
+					GFP_KERNEL);
+	if (!rt2x00dev->anchor) {
+		retval = -ENOMEM;
+		goto exit_free_reg;
+	}
+	init_usb_anchor(rt2x00dev->anchor);
+
+	retval = rt2x00lib_probe_dev(rt2x00dev);
+	if (retval)
+		goto exit_free_anchor;
+
+	return 0;
+
+exit_free_anchor:
+	usb_kill_anchored_urbs(rt2x00dev->anchor);
+
+exit_free_reg:
+	rt2x00usb_free_reg(rt2x00dev);
+
+exit_free_device:
+	ieee80211_free_hw(hw);
+
+exit_put_device:
+	usb_put_dev(usb_dev);
+
+	usb_set_intfdata(usb_intf, NULL);
+
+	return retval;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_probe);
+
+void rt2x00usb_disconnect(struct usb_interface *usb_intf)
+{
+	struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
+	struct rt2x00_dev *rt2x00dev = hw->priv;
+
+	/*
+	 * Free all allocated data.
+	 */
+	rt2x00lib_remove_dev(rt2x00dev);
+	rt2x00usb_free_reg(rt2x00dev);
+	ieee80211_free_hw(hw);
+
+	/*
+	 * Free the USB device data.
+	 */
+	usb_set_intfdata(usb_intf, NULL);
+	usb_put_dev(interface_to_usbdev(usb_intf));
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_disconnect);
+
+#ifdef CONFIG_PM
+int rt2x00usb_suspend(struct usb_interface *usb_intf, pm_message_t state)
+{
+	struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
+	struct rt2x00_dev *rt2x00dev = hw->priv;
+
+	return rt2x00lib_suspend(rt2x00dev);
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_suspend);
+
+int rt2x00usb_resume(struct usb_interface *usb_intf)
+{
+	struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
+	struct rt2x00_dev *rt2x00dev = hw->priv;
+
+	return rt2x00lib_resume(rt2x00dev);
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_resume);
+#endif /* CONFIG_PM */
+
+/*
+ * rt2x00usb module information.
+ */
+MODULE_AUTHOR(DRV_PROJECT);
+MODULE_VERSION(DRV_VERSION);
+MODULE_DESCRIPTION("rt2x00 usb library");
+MODULE_LICENSE("GPL");