xref: /linux/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c (revision ebf68996de0ab250c5d520eb2291ab65643e9a1e)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 	Copyright (C) 2010 Willow Garage <http://www.willowgarage.com>
4 	Copyright (C) 2004 - 2010 Ivo van Doorn <IvDoorn@gmail.com>
5 	<http://rt2x00.serialmonkey.com>
6 
7  */
8 
9 /*
10 	Module: rt2x00usb
11 	Abstract: rt2x00 generic usb device routines.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/slab.h>
17 #include <linux/usb.h>
18 #include <linux/bug.h>
19 
20 #include "rt2x00.h"
21 #include "rt2x00usb.h"
22 
23 static bool rt2x00usb_check_usb_error(struct rt2x00_dev *rt2x00dev, int status)
24 {
25 	if (status == -ENODEV || status == -ENOENT)
26 		return true;
27 
28 	if (status == -EPROTO || status == -ETIMEDOUT)
29 		rt2x00dev->num_proto_errs++;
30 	else
31 		rt2x00dev->num_proto_errs = 0;
32 
33 	if (rt2x00dev->num_proto_errs > 3)
34 		return true;
35 
36 	return false;
37 }
38 
39 /*
40  * Interfacing with the HW.
41  */
42 int rt2x00usb_vendor_request(struct rt2x00_dev *rt2x00dev,
43 			     const u8 request, const u8 requesttype,
44 			     const u16 offset, const u16 value,
45 			     void *buffer, const u16 buffer_length,
46 			     const int timeout)
47 {
48 	struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
49 	int status;
50 	unsigned int pipe =
51 	    (requesttype == USB_VENDOR_REQUEST_IN) ?
52 	    usb_rcvctrlpipe(usb_dev, 0) : usb_sndctrlpipe(usb_dev, 0);
53 	unsigned long expire = jiffies + msecs_to_jiffies(timeout);
54 
55 	if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
56 		return -ENODEV;
57 
58 	do {
59 		status = usb_control_msg(usb_dev, pipe, request, requesttype,
60 					 value, offset, buffer, buffer_length,
61 					 timeout / 2);
62 		if (status >= 0)
63 			return 0;
64 
65 		if (rt2x00usb_check_usb_error(rt2x00dev, status)) {
66 			/* Device has disappeared. */
67 			clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
68 			break;
69 		}
70 	} while (time_before(jiffies, expire));
71 
72 	rt2x00_err(rt2x00dev,
73 		   "Vendor Request 0x%02x failed for offset 0x%04x with error %d\n",
74 		   request, offset, status);
75 
76 	return status;
77 }
78 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request);
79 
80 int rt2x00usb_vendor_req_buff_lock(struct rt2x00_dev *rt2x00dev,
81 				   const u8 request, const u8 requesttype,
82 				   const u16 offset, void *buffer,
83 				   const u16 buffer_length, const int timeout)
84 {
85 	int status;
86 
87 	BUG_ON(!mutex_is_locked(&rt2x00dev->csr_mutex));
88 
89 	/*
90 	 * Check for Cache availability.
91 	 */
92 	if (unlikely(!rt2x00dev->csr.cache || buffer_length > CSR_CACHE_SIZE)) {
93 		rt2x00_err(rt2x00dev, "CSR cache not available\n");
94 		return -ENOMEM;
95 	}
96 
97 	if (requesttype == USB_VENDOR_REQUEST_OUT)
98 		memcpy(rt2x00dev->csr.cache, buffer, buffer_length);
99 
100 	status = rt2x00usb_vendor_request(rt2x00dev, request, requesttype,
101 					  offset, 0, rt2x00dev->csr.cache,
102 					  buffer_length, timeout);
103 
104 	if (!status && requesttype == USB_VENDOR_REQUEST_IN)
105 		memcpy(buffer, rt2x00dev->csr.cache, buffer_length);
106 
107 	return status;
108 }
109 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_req_buff_lock);
110 
111 int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
112 				  const u8 request, const u8 requesttype,
113 				  const u16 offset, void *buffer,
114 				  const u16 buffer_length)
115 {
116 	int status = 0;
117 	unsigned char *tb;
118 	u16 off, len, bsize;
119 
120 	mutex_lock(&rt2x00dev->csr_mutex);
121 
122 	tb  = (char *)buffer;
123 	off = offset;
124 	len = buffer_length;
125 	while (len && !status) {
126 		bsize = min_t(u16, CSR_CACHE_SIZE, len);
127 		status = rt2x00usb_vendor_req_buff_lock(rt2x00dev, request,
128 							requesttype, off, tb,
129 							bsize, REGISTER_TIMEOUT);
130 
131 		tb  += bsize;
132 		len -= bsize;
133 		off += bsize;
134 	}
135 
136 	mutex_unlock(&rt2x00dev->csr_mutex);
137 
138 	return status;
139 }
140 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request_buff);
141 
142 int rt2x00usb_regbusy_read(struct rt2x00_dev *rt2x00dev,
143 			   const unsigned int offset,
144 			   const struct rt2x00_field32 field,
145 			   u32 *reg)
146 {
147 	unsigned int i;
148 
149 	if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
150 		return -ENODEV;
151 
152 	for (i = 0; i < REGISTER_USB_BUSY_COUNT; i++) {
153 		*reg = rt2x00usb_register_read_lock(rt2x00dev, offset);
154 		if (!rt2x00_get_field32(*reg, field))
155 			return 1;
156 		udelay(REGISTER_BUSY_DELAY);
157 	}
158 
159 	rt2x00_err(rt2x00dev, "Indirect register access failed: offset=0x%.08x, value=0x%.08x\n",
160 		   offset, *reg);
161 	*reg = ~0;
162 
163 	return 0;
164 }
165 EXPORT_SYMBOL_GPL(rt2x00usb_regbusy_read);
166 
167 
168 struct rt2x00_async_read_data {
169 	__le32 reg;
170 	struct usb_ctrlrequest cr;
171 	struct rt2x00_dev *rt2x00dev;
172 	bool (*callback)(struct rt2x00_dev *, int, u32);
173 };
174 
175 static void rt2x00usb_register_read_async_cb(struct urb *urb)
176 {
177 	struct rt2x00_async_read_data *rd = urb->context;
178 	if (rd->callback(rd->rt2x00dev, urb->status, le32_to_cpu(rd->reg))) {
179 		usb_anchor_urb(urb, rd->rt2x00dev->anchor);
180 		if (usb_submit_urb(urb, GFP_ATOMIC) < 0) {
181 			usb_unanchor_urb(urb);
182 			kfree(rd);
183 		}
184 	} else
185 		kfree(rd);
186 }
187 
188 void rt2x00usb_register_read_async(struct rt2x00_dev *rt2x00dev,
189 				   const unsigned int offset,
190 				   bool (*callback)(struct rt2x00_dev*, int, u32))
191 {
192 	struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
193 	struct urb *urb;
194 	struct rt2x00_async_read_data *rd;
195 
196 	rd = kmalloc(sizeof(*rd), GFP_ATOMIC);
197 	if (!rd)
198 		return;
199 
200 	urb = usb_alloc_urb(0, GFP_ATOMIC);
201 	if (!urb) {
202 		kfree(rd);
203 		return;
204 	}
205 
206 	rd->rt2x00dev = rt2x00dev;
207 	rd->callback = callback;
208 	rd->cr.bRequestType = USB_VENDOR_REQUEST_IN;
209 	rd->cr.bRequest = USB_MULTI_READ;
210 	rd->cr.wValue = 0;
211 	rd->cr.wIndex = cpu_to_le16(offset);
212 	rd->cr.wLength = cpu_to_le16(sizeof(u32));
213 
214 	usb_fill_control_urb(urb, usb_dev, usb_rcvctrlpipe(usb_dev, 0),
215 			     (unsigned char *)(&rd->cr), &rd->reg, sizeof(rd->reg),
216 			     rt2x00usb_register_read_async_cb, rd);
217 	usb_anchor_urb(urb, rt2x00dev->anchor);
218 	if (usb_submit_urb(urb, GFP_ATOMIC) < 0) {
219 		usb_unanchor_urb(urb);
220 		kfree(rd);
221 	}
222 	usb_free_urb(urb);
223 }
224 EXPORT_SYMBOL_GPL(rt2x00usb_register_read_async);
225 
226 /*
227  * TX data handlers.
228  */
229 static void rt2x00usb_work_txdone_entry(struct queue_entry *entry)
230 {
231 	/*
232 	 * If the transfer to hardware succeeded, it does not mean the
233 	 * frame was send out correctly. It only means the frame
234 	 * was successfully pushed to the hardware, we have no
235 	 * way to determine the transmission status right now.
236 	 * (Only indirectly by looking at the failed TX counters
237 	 * in the register).
238 	 */
239 	if (test_bit(ENTRY_DATA_IO_FAILED, &entry->flags))
240 		rt2x00lib_txdone_noinfo(entry, TXDONE_FAILURE);
241 	else
242 		rt2x00lib_txdone_noinfo(entry, TXDONE_UNKNOWN);
243 }
244 
245 static void rt2x00usb_work_txdone(struct work_struct *work)
246 {
247 	struct rt2x00_dev *rt2x00dev =
248 	    container_of(work, struct rt2x00_dev, txdone_work);
249 	struct data_queue *queue;
250 	struct queue_entry *entry;
251 
252 	tx_queue_for_each(rt2x00dev, queue) {
253 		while (!rt2x00queue_empty(queue)) {
254 			entry = rt2x00queue_get_entry(queue, Q_INDEX_DONE);
255 
256 			if (test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags) ||
257 			    !test_bit(ENTRY_DATA_STATUS_PENDING, &entry->flags))
258 				break;
259 
260 			rt2x00usb_work_txdone_entry(entry);
261 		}
262 	}
263 }
264 
265 static void rt2x00usb_interrupt_txdone(struct urb *urb)
266 {
267 	struct queue_entry *entry = (struct queue_entry *)urb->context;
268 	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
269 
270 	if (!test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
271 		return;
272 	/*
273 	 * Check if the frame was correctly uploaded
274 	 */
275 	if (urb->status)
276 		set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
277 	/*
278 	 * Report the frame as DMA done
279 	 */
280 	rt2x00lib_dmadone(entry);
281 
282 	if (rt2x00dev->ops->lib->tx_dma_done)
283 		rt2x00dev->ops->lib->tx_dma_done(entry);
284 	/*
285 	 * Schedule the delayed work for reading the TX status
286 	 * from the device.
287 	 */
288 	if (!rt2x00_has_cap_flag(rt2x00dev, REQUIRE_TXSTATUS_FIFO) ||
289 	    !kfifo_is_empty(&rt2x00dev->txstatus_fifo))
290 		queue_work(rt2x00dev->workqueue, &rt2x00dev->txdone_work);
291 }
292 
293 static bool rt2x00usb_kick_tx_entry(struct queue_entry *entry, void *data)
294 {
295 	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
296 	struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
297 	struct queue_entry_priv_usb *entry_priv = entry->priv_data;
298 	u32 length;
299 	int status;
300 
301 	if (!test_and_clear_bit(ENTRY_DATA_PENDING, &entry->flags) ||
302 	    test_bit(ENTRY_DATA_STATUS_PENDING, &entry->flags))
303 		return false;
304 
305 	/*
306 	 * USB devices require certain padding at the end of each frame
307 	 * and urb. Those paddings are not included in skbs. Pass entry
308 	 * to the driver to determine what the overall length should be.
309 	 */
310 	length = rt2x00dev->ops->lib->get_tx_data_len(entry);
311 
312 	status = skb_padto(entry->skb, length);
313 	if (unlikely(status)) {
314 		/* TODO: report something more appropriate than IO_FAILED. */
315 		rt2x00_warn(rt2x00dev, "TX SKB padding error, out of memory\n");
316 		set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
317 		rt2x00lib_dmadone(entry);
318 
319 		return false;
320 	}
321 
322 	usb_fill_bulk_urb(entry_priv->urb, usb_dev,
323 			  usb_sndbulkpipe(usb_dev, entry->queue->usb_endpoint),
324 			  entry->skb->data, length,
325 			  rt2x00usb_interrupt_txdone, entry);
326 
327 	status = usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
328 	if (status) {
329 		if (rt2x00usb_check_usb_error(rt2x00dev, status))
330 			clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
331 		set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
332 		rt2x00lib_dmadone(entry);
333 	}
334 
335 	return false;
336 }
337 
338 /*
339  * RX data handlers.
340  */
341 static void rt2x00usb_work_rxdone(struct work_struct *work)
342 {
343 	struct rt2x00_dev *rt2x00dev =
344 	    container_of(work, struct rt2x00_dev, rxdone_work);
345 	struct queue_entry *entry;
346 	struct skb_frame_desc *skbdesc;
347 	u8 rxd[32];
348 
349 	while (!rt2x00queue_empty(rt2x00dev->rx)) {
350 		entry = rt2x00queue_get_entry(rt2x00dev->rx, Q_INDEX_DONE);
351 
352 		if (test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags) ||
353 		    !test_bit(ENTRY_DATA_STATUS_PENDING, &entry->flags))
354 			break;
355 
356 		/*
357 		 * Fill in desc fields of the skb descriptor
358 		 */
359 		skbdesc = get_skb_frame_desc(entry->skb);
360 		skbdesc->desc = rxd;
361 		skbdesc->desc_len = entry->queue->desc_size;
362 
363 		/*
364 		 * Send the frame to rt2x00lib for further processing.
365 		 */
366 		rt2x00lib_rxdone(entry, GFP_KERNEL);
367 	}
368 }
369 
370 static void rt2x00usb_interrupt_rxdone(struct urb *urb)
371 {
372 	struct queue_entry *entry = (struct queue_entry *)urb->context;
373 	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
374 
375 	if (!test_and_clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
376 		return;
377 
378 	/*
379 	 * Report the frame as DMA done
380 	 */
381 	rt2x00lib_dmadone(entry);
382 
383 	/*
384 	 * Check if the received data is simply too small
385 	 * to be actually valid, or if the urb is signaling
386 	 * a problem.
387 	 */
388 	if (urb->actual_length < entry->queue->desc_size || urb->status)
389 		set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
390 
391 	/*
392 	 * Schedule the delayed work for reading the RX status
393 	 * from the device.
394 	 */
395 	queue_work(rt2x00dev->workqueue, &rt2x00dev->rxdone_work);
396 }
397 
398 static bool rt2x00usb_kick_rx_entry(struct queue_entry *entry, void *data)
399 {
400 	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
401 	struct usb_device *usb_dev = to_usb_device_intf(rt2x00dev->dev);
402 	struct queue_entry_priv_usb *entry_priv = entry->priv_data;
403 	int status;
404 
405 	if (test_and_set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags) ||
406 	    test_bit(ENTRY_DATA_STATUS_PENDING, &entry->flags))
407 		return false;
408 
409 	rt2x00lib_dmastart(entry);
410 
411 	usb_fill_bulk_urb(entry_priv->urb, usb_dev,
412 			  usb_rcvbulkpipe(usb_dev, entry->queue->usb_endpoint),
413 			  entry->skb->data, entry->skb->len,
414 			  rt2x00usb_interrupt_rxdone, entry);
415 
416 	status = usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
417 	if (status) {
418 		if (rt2x00usb_check_usb_error(rt2x00dev, status))
419 			clear_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags);
420 		set_bit(ENTRY_DATA_IO_FAILED, &entry->flags);
421 		rt2x00lib_dmadone(entry);
422 	}
423 
424 	return false;
425 }
426 
427 void rt2x00usb_kick_queue(struct data_queue *queue)
428 {
429 	switch (queue->qid) {
430 	case QID_AC_VO:
431 	case QID_AC_VI:
432 	case QID_AC_BE:
433 	case QID_AC_BK:
434 		if (!rt2x00queue_empty(queue))
435 			rt2x00queue_for_each_entry(queue,
436 						   Q_INDEX_DONE,
437 						   Q_INDEX,
438 						   NULL,
439 						   rt2x00usb_kick_tx_entry);
440 		break;
441 	case QID_RX:
442 		if (!rt2x00queue_full(queue))
443 			rt2x00queue_for_each_entry(queue,
444 						   Q_INDEX,
445 						   Q_INDEX_DONE,
446 						   NULL,
447 						   rt2x00usb_kick_rx_entry);
448 		break;
449 	default:
450 		break;
451 	}
452 }
453 EXPORT_SYMBOL_GPL(rt2x00usb_kick_queue);
454 
455 static bool rt2x00usb_flush_entry(struct queue_entry *entry, void *data)
456 {
457 	struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
458 	struct queue_entry_priv_usb *entry_priv = entry->priv_data;
459 	struct queue_entry_priv_usb_bcn *bcn_priv = entry->priv_data;
460 
461 	if (!test_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
462 		return false;
463 
464 	usb_kill_urb(entry_priv->urb);
465 
466 	/*
467 	 * Kill guardian urb (if required by driver).
468 	 */
469 	if ((entry->queue->qid == QID_BEACON) &&
470 	    (rt2x00_has_cap_flag(rt2x00dev, REQUIRE_BEACON_GUARD)))
471 		usb_kill_urb(bcn_priv->guardian_urb);
472 
473 	return false;
474 }
475 
476 void rt2x00usb_flush_queue(struct data_queue *queue, bool drop)
477 {
478 	struct work_struct *completion;
479 	unsigned int i;
480 
481 	if (drop)
482 		rt2x00queue_for_each_entry(queue, Q_INDEX_DONE, Q_INDEX, NULL,
483 					   rt2x00usb_flush_entry);
484 
485 	/*
486 	 * Obtain the queue completion handler
487 	 */
488 	switch (queue->qid) {
489 	case QID_AC_VO:
490 	case QID_AC_VI:
491 	case QID_AC_BE:
492 	case QID_AC_BK:
493 		completion = &queue->rt2x00dev->txdone_work;
494 		break;
495 	case QID_RX:
496 		completion = &queue->rt2x00dev->rxdone_work;
497 		break;
498 	default:
499 		return;
500 	}
501 
502 	for (i = 0; i < 10; i++) {
503 		/*
504 		 * Check if the driver is already done, otherwise we
505 		 * have to sleep a little while to give the driver/hw
506 		 * the oppurtunity to complete interrupt process itself.
507 		 */
508 		if (rt2x00queue_empty(queue))
509 			break;
510 
511 		/*
512 		 * Schedule the completion handler manually, when this
513 		 * worker function runs, it should cleanup the queue.
514 		 */
515 		queue_work(queue->rt2x00dev->workqueue, completion);
516 
517 		/*
518 		 * Wait for a little while to give the driver
519 		 * the oppurtunity to recover itself.
520 		 */
521 		msleep(50);
522 	}
523 }
524 EXPORT_SYMBOL_GPL(rt2x00usb_flush_queue);
525 
526 static void rt2x00usb_watchdog_tx_dma(struct data_queue *queue)
527 {
528 	rt2x00_warn(queue->rt2x00dev, "TX queue %d DMA timed out, invoke forced forced reset\n",
529 		    queue->qid);
530 
531 	rt2x00queue_stop_queue(queue);
532 	rt2x00queue_flush_queue(queue, true);
533 	rt2x00queue_start_queue(queue);
534 }
535 
536 static int rt2x00usb_dma_timeout(struct data_queue *queue)
537 {
538 	struct queue_entry *entry;
539 
540 	entry = rt2x00queue_get_entry(queue, Q_INDEX_DMA_DONE);
541 	return rt2x00queue_dma_timeout(entry);
542 }
543 
544 void rt2x00usb_watchdog(struct rt2x00_dev *rt2x00dev)
545 {
546 	struct data_queue *queue;
547 
548 	tx_queue_for_each(rt2x00dev, queue) {
549 		if (!rt2x00queue_empty(queue)) {
550 			if (rt2x00usb_dma_timeout(queue))
551 				rt2x00usb_watchdog_tx_dma(queue);
552 		}
553 	}
554 }
555 EXPORT_SYMBOL_GPL(rt2x00usb_watchdog);
556 
557 /*
558  * Radio handlers
559  */
560 void rt2x00usb_disable_radio(struct rt2x00_dev *rt2x00dev)
561 {
562 	rt2x00usb_vendor_request_sw(rt2x00dev, USB_RX_CONTROL, 0, 0,
563 				    REGISTER_TIMEOUT);
564 }
565 EXPORT_SYMBOL_GPL(rt2x00usb_disable_radio);
566 
567 /*
568  * Device initialization handlers.
569  */
570 void rt2x00usb_clear_entry(struct queue_entry *entry)
571 {
572 	entry->flags = 0;
573 
574 	if (entry->queue->qid == QID_RX)
575 		rt2x00usb_kick_rx_entry(entry, NULL);
576 }
577 EXPORT_SYMBOL_GPL(rt2x00usb_clear_entry);
578 
579 static void rt2x00usb_assign_endpoint(struct data_queue *queue,
580 				      struct usb_endpoint_descriptor *ep_desc)
581 {
582 	struct usb_device *usb_dev = to_usb_device_intf(queue->rt2x00dev->dev);
583 	int pipe;
584 
585 	queue->usb_endpoint = usb_endpoint_num(ep_desc);
586 
587 	if (queue->qid == QID_RX) {
588 		pipe = usb_rcvbulkpipe(usb_dev, queue->usb_endpoint);
589 		queue->usb_maxpacket = usb_maxpacket(usb_dev, pipe, 0);
590 	} else {
591 		pipe = usb_sndbulkpipe(usb_dev, queue->usb_endpoint);
592 		queue->usb_maxpacket = usb_maxpacket(usb_dev, pipe, 1);
593 	}
594 
595 	if (!queue->usb_maxpacket)
596 		queue->usb_maxpacket = 1;
597 }
598 
599 static int rt2x00usb_find_endpoints(struct rt2x00_dev *rt2x00dev)
600 {
601 	struct usb_interface *intf = to_usb_interface(rt2x00dev->dev);
602 	struct usb_host_interface *intf_desc = intf->cur_altsetting;
603 	struct usb_endpoint_descriptor *ep_desc;
604 	struct data_queue *queue = rt2x00dev->tx;
605 	struct usb_endpoint_descriptor *tx_ep_desc = NULL;
606 	unsigned int i;
607 
608 	/*
609 	 * Walk through all available endpoints to search for "bulk in"
610 	 * and "bulk out" endpoints. When we find such endpoints collect
611 	 * the information we need from the descriptor and assign it
612 	 * to the queue.
613 	 */
614 	for (i = 0; i < intf_desc->desc.bNumEndpoints; i++) {
615 		ep_desc = &intf_desc->endpoint[i].desc;
616 
617 		if (usb_endpoint_is_bulk_in(ep_desc)) {
618 			rt2x00usb_assign_endpoint(rt2x00dev->rx, ep_desc);
619 		} else if (usb_endpoint_is_bulk_out(ep_desc) &&
620 			   (queue != queue_end(rt2x00dev))) {
621 			rt2x00usb_assign_endpoint(queue, ep_desc);
622 			queue = queue_next(queue);
623 
624 			tx_ep_desc = ep_desc;
625 		}
626 	}
627 
628 	/*
629 	 * At least 1 endpoint for RX and 1 endpoint for TX must be available.
630 	 */
631 	if (!rt2x00dev->rx->usb_endpoint || !rt2x00dev->tx->usb_endpoint) {
632 		rt2x00_err(rt2x00dev, "Bulk-in/Bulk-out endpoints not found\n");
633 		return -EPIPE;
634 	}
635 
636 	/*
637 	 * It might be possible not all queues have a dedicated endpoint.
638 	 * Loop through all TX queues and copy the endpoint information
639 	 * which we have gathered from already assigned endpoints.
640 	 */
641 	txall_queue_for_each(rt2x00dev, queue) {
642 		if (!queue->usb_endpoint)
643 			rt2x00usb_assign_endpoint(queue, tx_ep_desc);
644 	}
645 
646 	return 0;
647 }
648 
649 static int rt2x00usb_alloc_entries(struct data_queue *queue)
650 {
651 	struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
652 	struct queue_entry_priv_usb *entry_priv;
653 	struct queue_entry_priv_usb_bcn *bcn_priv;
654 	unsigned int i;
655 
656 	for (i = 0; i < queue->limit; i++) {
657 		entry_priv = queue->entries[i].priv_data;
658 		entry_priv->urb = usb_alloc_urb(0, GFP_KERNEL);
659 		if (!entry_priv->urb)
660 			return -ENOMEM;
661 	}
662 
663 	/*
664 	 * If this is not the beacon queue or
665 	 * no guardian byte was required for the beacon,
666 	 * then we are done.
667 	 */
668 	if (queue->qid != QID_BEACON ||
669 	    !rt2x00_has_cap_flag(rt2x00dev, REQUIRE_BEACON_GUARD))
670 		return 0;
671 
672 	for (i = 0; i < queue->limit; i++) {
673 		bcn_priv = queue->entries[i].priv_data;
674 		bcn_priv->guardian_urb = usb_alloc_urb(0, GFP_KERNEL);
675 		if (!bcn_priv->guardian_urb)
676 			return -ENOMEM;
677 	}
678 
679 	return 0;
680 }
681 
682 static void rt2x00usb_free_entries(struct data_queue *queue)
683 {
684 	struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
685 	struct queue_entry_priv_usb *entry_priv;
686 	struct queue_entry_priv_usb_bcn *bcn_priv;
687 	unsigned int i;
688 
689 	if (!queue->entries)
690 		return;
691 
692 	for (i = 0; i < queue->limit; i++) {
693 		entry_priv = queue->entries[i].priv_data;
694 		usb_kill_urb(entry_priv->urb);
695 		usb_free_urb(entry_priv->urb);
696 	}
697 
698 	/*
699 	 * If this is not the beacon queue or
700 	 * no guardian byte was required for the beacon,
701 	 * then we are done.
702 	 */
703 	if (queue->qid != QID_BEACON ||
704 	    !rt2x00_has_cap_flag(rt2x00dev, REQUIRE_BEACON_GUARD))
705 		return;
706 
707 	for (i = 0; i < queue->limit; i++) {
708 		bcn_priv = queue->entries[i].priv_data;
709 		usb_kill_urb(bcn_priv->guardian_urb);
710 		usb_free_urb(bcn_priv->guardian_urb);
711 	}
712 }
713 
714 int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
715 {
716 	struct data_queue *queue;
717 	int status;
718 
719 	/*
720 	 * Find endpoints for each queue
721 	 */
722 	status = rt2x00usb_find_endpoints(rt2x00dev);
723 	if (status)
724 		goto exit;
725 
726 	/*
727 	 * Allocate DMA
728 	 */
729 	queue_for_each(rt2x00dev, queue) {
730 		status = rt2x00usb_alloc_entries(queue);
731 		if (status)
732 			goto exit;
733 	}
734 
735 	return 0;
736 
737 exit:
738 	rt2x00usb_uninitialize(rt2x00dev);
739 
740 	return status;
741 }
742 EXPORT_SYMBOL_GPL(rt2x00usb_initialize);
743 
744 void rt2x00usb_uninitialize(struct rt2x00_dev *rt2x00dev)
745 {
746 	struct data_queue *queue;
747 
748 	usb_kill_anchored_urbs(rt2x00dev->anchor);
749 	hrtimer_cancel(&rt2x00dev->txstatus_timer);
750 	cancel_work_sync(&rt2x00dev->rxdone_work);
751 	cancel_work_sync(&rt2x00dev->txdone_work);
752 
753 	queue_for_each(rt2x00dev, queue)
754 		rt2x00usb_free_entries(queue);
755 }
756 EXPORT_SYMBOL_GPL(rt2x00usb_uninitialize);
757 
758 /*
759  * USB driver handlers.
760  */
761 static void rt2x00usb_free_reg(struct rt2x00_dev *rt2x00dev)
762 {
763 	kfree(rt2x00dev->rf);
764 	rt2x00dev->rf = NULL;
765 
766 	kfree(rt2x00dev->eeprom);
767 	rt2x00dev->eeprom = NULL;
768 
769 	kfree(rt2x00dev->csr.cache);
770 	rt2x00dev->csr.cache = NULL;
771 }
772 
773 static int rt2x00usb_alloc_reg(struct rt2x00_dev *rt2x00dev)
774 {
775 	rt2x00dev->csr.cache = kzalloc(CSR_CACHE_SIZE, GFP_KERNEL);
776 	if (!rt2x00dev->csr.cache)
777 		goto exit;
778 
779 	rt2x00dev->eeprom = kzalloc(rt2x00dev->ops->eeprom_size, GFP_KERNEL);
780 	if (!rt2x00dev->eeprom)
781 		goto exit;
782 
783 	rt2x00dev->rf = kzalloc(rt2x00dev->ops->rf_size, GFP_KERNEL);
784 	if (!rt2x00dev->rf)
785 		goto exit;
786 
787 	return 0;
788 
789 exit:
790 	rt2x00_probe_err("Failed to allocate registers\n");
791 
792 	rt2x00usb_free_reg(rt2x00dev);
793 
794 	return -ENOMEM;
795 }
796 
797 int rt2x00usb_probe(struct usb_interface *usb_intf,
798 		    const struct rt2x00_ops *ops)
799 {
800 	struct usb_device *usb_dev = interface_to_usbdev(usb_intf);
801 	struct ieee80211_hw *hw;
802 	struct rt2x00_dev *rt2x00dev;
803 	int retval;
804 
805 	usb_dev = usb_get_dev(usb_dev);
806 	usb_reset_device(usb_dev);
807 
808 	hw = ieee80211_alloc_hw(sizeof(struct rt2x00_dev), ops->hw);
809 	if (!hw) {
810 		rt2x00_probe_err("Failed to allocate hardware\n");
811 		retval = -ENOMEM;
812 		goto exit_put_device;
813 	}
814 
815 	usb_set_intfdata(usb_intf, hw);
816 
817 	rt2x00dev = hw->priv;
818 	rt2x00dev->dev = &usb_intf->dev;
819 	rt2x00dev->ops = ops;
820 	rt2x00dev->hw = hw;
821 
822 	rt2x00_set_chip_intf(rt2x00dev, RT2X00_CHIP_INTF_USB);
823 
824 	INIT_WORK(&rt2x00dev->rxdone_work, rt2x00usb_work_rxdone);
825 	INIT_WORK(&rt2x00dev->txdone_work, rt2x00usb_work_txdone);
826 	hrtimer_init(&rt2x00dev->txstatus_timer, CLOCK_MONOTONIC,
827 		     HRTIMER_MODE_REL);
828 
829 	retval = rt2x00usb_alloc_reg(rt2x00dev);
830 	if (retval)
831 		goto exit_free_device;
832 
833 	rt2x00dev->anchor = devm_kmalloc(&usb_dev->dev,
834 					sizeof(struct usb_anchor),
835 					GFP_KERNEL);
836 	if (!rt2x00dev->anchor) {
837 		retval = -ENOMEM;
838 		goto exit_free_reg;
839 	}
840 	init_usb_anchor(rt2x00dev->anchor);
841 
842 	retval = rt2x00lib_probe_dev(rt2x00dev);
843 	if (retval)
844 		goto exit_free_anchor;
845 
846 	return 0;
847 
848 exit_free_anchor:
849 	usb_kill_anchored_urbs(rt2x00dev->anchor);
850 
851 exit_free_reg:
852 	rt2x00usb_free_reg(rt2x00dev);
853 
854 exit_free_device:
855 	ieee80211_free_hw(hw);
856 
857 exit_put_device:
858 	usb_put_dev(usb_dev);
859 
860 	usb_set_intfdata(usb_intf, NULL);
861 
862 	return retval;
863 }
864 EXPORT_SYMBOL_GPL(rt2x00usb_probe);
865 
866 void rt2x00usb_disconnect(struct usb_interface *usb_intf)
867 {
868 	struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
869 	struct rt2x00_dev *rt2x00dev = hw->priv;
870 
871 	/*
872 	 * Free all allocated data.
873 	 */
874 	rt2x00lib_remove_dev(rt2x00dev);
875 	rt2x00usb_free_reg(rt2x00dev);
876 	ieee80211_free_hw(hw);
877 
878 	/*
879 	 * Free the USB device data.
880 	 */
881 	usb_set_intfdata(usb_intf, NULL);
882 	usb_put_dev(interface_to_usbdev(usb_intf));
883 }
884 EXPORT_SYMBOL_GPL(rt2x00usb_disconnect);
885 
886 #ifdef CONFIG_PM
887 int rt2x00usb_suspend(struct usb_interface *usb_intf, pm_message_t state)
888 {
889 	struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
890 	struct rt2x00_dev *rt2x00dev = hw->priv;
891 
892 	return rt2x00lib_suspend(rt2x00dev, state);
893 }
894 EXPORT_SYMBOL_GPL(rt2x00usb_suspend);
895 
896 int rt2x00usb_resume(struct usb_interface *usb_intf)
897 {
898 	struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
899 	struct rt2x00_dev *rt2x00dev = hw->priv;
900 
901 	return rt2x00lib_resume(rt2x00dev);
902 }
903 EXPORT_SYMBOL_GPL(rt2x00usb_resume);
904 #endif /* CONFIG_PM */
905 
906 /*
907  * rt2x00usb module information.
908  */
909 MODULE_AUTHOR(DRV_PROJECT);
910 MODULE_VERSION(DRV_VERSION);
911 MODULE_DESCRIPTION("rt2x00 usb library");
912 MODULE_LICENSE("GPL");
913