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rt2x00: Centralize allocation of RX skbs.
[linux-2.6] / drivers / net / wireless / rt2x00 / rt2x00usb.c
1 /*
2         Copyright (C) 2004 - 2008 rt2x00 SourceForge Project
3         <http://rt2x00.serialmonkey.com>
4
5         This program is free software; you can redistribute it and/or modify
6         it under the terms of the GNU General Public License as published by
7         the Free Software Foundation; either version 2 of the License, or
8         (at your option) any later version.
9
10         This program is distributed in the hope that it will be useful,
11         but WITHOUT ANY WARRANTY; without even the implied warranty of
12         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13         GNU General Public License for more details.
14
15         You should have received a copy of the GNU General Public License
16         along with this program; if not, write to the
17         Free Software Foundation, Inc.,
18         59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20
21 /*
22         Module: rt2x00usb
23         Abstract: rt2x00 generic usb device routines.
24  */
25
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/usb.h>
29 #include <linux/bug.h>
30
31 #include "rt2x00.h"
32 #include "rt2x00usb.h"
33
34 /*
35  * Interfacing with the HW.
36  */
37 int rt2x00usb_vendor_request(struct rt2x00_dev *rt2x00dev,
38                              const u8 request, const u8 requesttype,
39                              const u16 offset, const u16 value,
40                              void *buffer, const u16 buffer_length,
41                              const int timeout)
42 {
43         struct usb_device *usb_dev =
44                 interface_to_usbdev(to_usb_interface(rt2x00dev->dev));
45         int status;
46         unsigned int i;
47         unsigned int pipe =
48             (requesttype == USB_VENDOR_REQUEST_IN) ?
49             usb_rcvctrlpipe(usb_dev, 0) : usb_sndctrlpipe(usb_dev, 0);
50
51
52         for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
53                 status = usb_control_msg(usb_dev, pipe, request, requesttype,
54                                          value, offset, buffer, buffer_length,
55                                          timeout);
56                 if (status >= 0)
57                         return 0;
58
59                 /*
60                  * Check for errors
61                  * -ENODEV: Device has disappeared, no point continuing.
62                  * All other errors: Try again.
63                  */
64                 else if (status == -ENODEV)
65                         break;
66         }
67
68         ERROR(rt2x00dev,
69               "Vendor Request 0x%02x failed for offset 0x%04x with error %d.\n",
70               request, offset, status);
71
72         return status;
73 }
74 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request);
75
76 int rt2x00usb_vendor_req_buff_lock(struct rt2x00_dev *rt2x00dev,
77                                    const u8 request, const u8 requesttype,
78                                    const u16 offset, void *buffer,
79                                    const u16 buffer_length, const int timeout)
80 {
81         int status;
82
83         BUG_ON(!mutex_is_locked(&rt2x00dev->usb_cache_mutex));
84
85         /*
86          * Check for Cache availability.
87          */
88         if (unlikely(!rt2x00dev->csr.cache || buffer_length > CSR_CACHE_SIZE)) {
89                 ERROR(rt2x00dev, "CSR cache not available.\n");
90                 return -ENOMEM;
91         }
92
93         if (requesttype == USB_VENDOR_REQUEST_OUT)
94                 memcpy(rt2x00dev->csr.cache, buffer, buffer_length);
95
96         status = rt2x00usb_vendor_request(rt2x00dev, request, requesttype,
97                                           offset, 0, rt2x00dev->csr.cache,
98                                           buffer_length, timeout);
99
100         if (!status && requesttype == USB_VENDOR_REQUEST_IN)
101                 memcpy(buffer, rt2x00dev->csr.cache, buffer_length);
102
103         return status;
104 }
105 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_req_buff_lock);
106
107 int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
108                                   const u8 request, const u8 requesttype,
109                                   const u16 offset, void *buffer,
110                                   const u16 buffer_length, const int timeout)
111 {
112         int status;
113
114         mutex_lock(&rt2x00dev->usb_cache_mutex);
115
116         status = rt2x00usb_vendor_req_buff_lock(rt2x00dev, request,
117                                                 requesttype, offset, buffer,
118                                                 buffer_length, timeout);
119
120         mutex_unlock(&rt2x00dev->usb_cache_mutex);
121
122         return status;
123 }
124 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request_buff);
125
126 /*
127  * TX data handlers.
128  */
129 static void rt2x00usb_interrupt_txdone(struct urb *urb)
130 {
131         struct queue_entry *entry = (struct queue_entry *)urb->context;
132         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
133         struct txdone_entry_desc txdesc;
134         enum data_queue_qid qid = skb_get_queue_mapping(entry->skb);
135
136         if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
137             !__test_and_clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
138                 return;
139
140         /*
141          * Remove the descriptor data from the buffer.
142          */
143         skb_pull(entry->skb, entry->queue->desc_size);
144
145         /*
146          * Obtain the status about this packet.
147          * Note that when the status is 0 it does not mean the
148          * frame was send out correctly. It only means the frame
149          * was succesfully pushed to the hardware, we have no
150          * way to determine the transmission status right now.
151          * (Only indirectly by looking at the failed TX counters
152          * in the register).
153          */
154         if (!urb->status)
155                 __set_bit(TXDONE_UNKNOWN, &txdesc.flags);
156         else
157                 __set_bit(TXDONE_FAILURE, &txdesc.flags);
158         txdesc.retry = 0;
159
160         rt2x00lib_txdone(entry, &txdesc);
161
162         /*
163          * Make this entry available for reuse.
164          */
165         entry->flags = 0;
166         rt2x00queue_index_inc(entry->queue, Q_INDEX_DONE);
167
168         /*
169          * If the data queue was below the threshold before the txdone
170          * handler we must make sure the packet queue in the mac80211 stack
171          * is reenabled when the txdone handler has finished.
172          */
173         if (!rt2x00queue_threshold(entry->queue))
174                 ieee80211_wake_queue(rt2x00dev->hw, qid);
175 }
176
177 int rt2x00usb_write_tx_data(struct queue_entry *entry)
178 {
179         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
180         struct usb_device *usb_dev =
181                 interface_to_usbdev(to_usb_interface(rt2x00dev->dev));
182         struct queue_entry_priv_usb *entry_priv = entry->priv_data;
183         struct skb_frame_desc *skbdesc;
184         u32 length;
185
186         /*
187          * Add the descriptor in front of the skb.
188          */
189         skb_push(entry->skb, entry->queue->desc_size);
190         memset(entry->skb->data, 0, entry->queue->desc_size);
191
192         /*
193          * Fill in skb descriptor
194          */
195         skbdesc = get_skb_frame_desc(entry->skb);
196         memset(skbdesc, 0, sizeof(*skbdesc));
197         skbdesc->desc = entry->skb->data;
198         skbdesc->desc_len = entry->queue->desc_size;
199         skbdesc->entry = entry;
200
201         /*
202          * USB devices cannot blindly pass the skb->len as the
203          * length of the data to usb_fill_bulk_urb. Pass the skb
204          * to the driver to determine what the length should be.
205          */
206         length = rt2x00dev->ops->lib->get_tx_data_len(rt2x00dev, entry->skb);
207
208         usb_fill_bulk_urb(entry_priv->urb, usb_dev,
209                           usb_sndbulkpipe(usb_dev, 1),
210                           entry->skb->data, length,
211                           rt2x00usb_interrupt_txdone, entry);
212
213         return 0;
214 }
215 EXPORT_SYMBOL_GPL(rt2x00usb_write_tx_data);
216
217 static inline void rt2x00usb_kick_tx_entry(struct queue_entry *entry)
218 {
219         struct queue_entry_priv_usb *entry_priv = entry->priv_data;
220
221         if (__test_and_clear_bit(ENTRY_DATA_PENDING, &entry->flags))
222                 usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
223 }
224
225 void rt2x00usb_kick_tx_queue(struct rt2x00_dev *rt2x00dev,
226                              const enum data_queue_qid qid)
227 {
228         struct data_queue *queue = rt2x00queue_get_queue(rt2x00dev, qid);
229         unsigned long irqflags;
230         unsigned int index;
231         unsigned int index_done;
232         unsigned int i;
233
234         /*
235          * Only protect the range we are going to loop over,
236          * if during our loop a extra entry is set to pending
237          * it should not be kicked during this run, since it
238          * is part of another TX operation.
239          */
240         spin_lock_irqsave(&queue->lock, irqflags);
241         index = queue->index[Q_INDEX];
242         index_done = queue->index[Q_INDEX_DONE];
243         spin_unlock_irqrestore(&queue->lock, irqflags);
244
245         /*
246          * Start from the TX done pointer, this guarentees that we will
247          * send out all frames in the correct order.
248          */
249         if (index_done < index) {
250                 for (i = index_done; i < index; i++)
251                         rt2x00usb_kick_tx_entry(&queue->entries[i]);
252         } else {
253                 for (i = index_done; i < queue->limit; i++)
254                         rt2x00usb_kick_tx_entry(&queue->entries[i]);
255
256                 for (i = 0; i < index; i++)
257                         rt2x00usb_kick_tx_entry(&queue->entries[i]);
258         }
259 }
260 EXPORT_SYMBOL_GPL(rt2x00usb_kick_tx_queue);
261
262 /*
263  * RX data handlers.
264  */
265 static void rt2x00usb_interrupt_rxdone(struct urb *urb)
266 {
267         struct queue_entry *entry = (struct queue_entry *)urb->context;
268         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
269         struct sk_buff *skb;
270         struct skb_frame_desc *skbdesc;
271         struct rxdone_entry_desc rxdesc;
272         u8 rxd[32];
273
274         if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
275             !test_and_clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
276                 return;
277
278         /*
279          * Check if the received data is simply too small
280          * to be actually valid, or if the urb is signaling
281          * a problem.
282          */
283         if (urb->actual_length < entry->queue->desc_size || urb->status)
284                 goto skip_entry;
285
286         /*
287          * Fill in skb descriptor
288          */
289         skbdesc = get_skb_frame_desc(entry->skb);
290         memset(skbdesc, 0, sizeof(*skbdesc));
291         skbdesc->entry = entry;
292         skbdesc->desc = rxd;
293         skbdesc->desc_len = entry->queue->desc_size;
294
295         memset(&rxdesc, 0, sizeof(rxdesc));
296         rt2x00dev->ops->lib->fill_rxdone(entry, &rxdesc);
297
298         /*
299          * Allocate a new sk buffer to replace the current one.
300          * If allocation fails, we should drop the current frame
301          * so we can recycle the existing sk buffer for the new frame.
302          */
303         skb = rt2x00queue_alloc_skb(entry->queue);
304         if (!skb)
305                 goto skip_entry;
306
307         /*
308          * Send the frame to rt2x00lib for further processing.
309          */
310         rt2x00lib_rxdone(entry, &rxdesc);
311
312         /*
313          * Replace current entry's skb with the newly allocated one,
314          * and reinitialize the urb.
315          */
316         entry->skb = skb;
317         urb->transfer_buffer = entry->skb->data;
318         urb->transfer_buffer_length = entry->skb->len;
319
320 skip_entry:
321         if (test_bit(DEVICE_ENABLED_RADIO, &entry->queue->rt2x00dev->flags)) {
322                 __set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
323                 usb_submit_urb(urb, GFP_ATOMIC);
324         }
325
326         rt2x00queue_index_inc(entry->queue, Q_INDEX);
327 }
328
329 /*
330  * Radio handlers
331  */
332 void rt2x00usb_disable_radio(struct rt2x00_dev *rt2x00dev)
333 {
334         struct queue_entry_priv_usb *entry_priv;
335         struct queue_entry_priv_usb_bcn *bcn_priv;
336         unsigned int i;
337
338         rt2x00usb_vendor_request_sw(rt2x00dev, USB_RX_CONTROL, 0, 0,
339                                     REGISTER_TIMEOUT);
340
341         /*
342          * Cancel all queues.
343          */
344         for (i = 0; i < rt2x00dev->rx->limit; i++) {
345                 entry_priv = rt2x00dev->rx->entries[i].priv_data;
346                 usb_kill_urb(entry_priv->urb);
347         }
348
349         /*
350          * Kill guardian urb (if required by driver).
351          */
352         if (!test_bit(DRIVER_REQUIRE_BEACON_GUARD, &rt2x00dev->flags))
353                 return;
354
355         for (i = 0; i < rt2x00dev->bcn->limit; i++) {
356                 bcn_priv = rt2x00dev->bcn->entries[i].priv_data;
357                 if (bcn_priv->guardian_urb)
358                         usb_kill_urb(bcn_priv->guardian_urb);
359         }
360 }
361 EXPORT_SYMBOL_GPL(rt2x00usb_disable_radio);
362
363 /*
364  * Device initialization handlers.
365  */
366 void rt2x00usb_init_rxentry(struct rt2x00_dev *rt2x00dev,
367                             struct queue_entry *entry)
368 {
369         struct usb_device *usb_dev =
370                 interface_to_usbdev(to_usb_interface(rt2x00dev->dev));
371         struct queue_entry_priv_usb *entry_priv = entry->priv_data;
372
373         usb_fill_bulk_urb(entry_priv->urb, usb_dev,
374                           usb_rcvbulkpipe(usb_dev, 1),
375                           entry->skb->data, entry->skb->len,
376                           rt2x00usb_interrupt_rxdone, entry);
377
378         __set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
379         usb_submit_urb(entry_priv->urb, GFP_ATOMIC);
380 }
381 EXPORT_SYMBOL_GPL(rt2x00usb_init_rxentry);
382
383 void rt2x00usb_init_txentry(struct rt2x00_dev *rt2x00dev,
384                             struct queue_entry *entry)
385 {
386         entry->flags = 0;
387 }
388 EXPORT_SYMBOL_GPL(rt2x00usb_init_txentry);
389
390 static int rt2x00usb_alloc_urb(struct rt2x00_dev *rt2x00dev,
391                                struct data_queue *queue)
392 {
393         struct queue_entry_priv_usb *entry_priv;
394         struct queue_entry_priv_usb_bcn *bcn_priv;
395         unsigned int i;
396
397         for (i = 0; i < queue->limit; i++) {
398                 entry_priv = queue->entries[i].priv_data;
399                 entry_priv->urb = usb_alloc_urb(0, GFP_KERNEL);
400                 if (!entry_priv->urb)
401                         return -ENOMEM;
402         }
403
404         /*
405          * If this is not the beacon queue or
406          * no guardian byte was required for the beacon,
407          * then we are done.
408          */
409         if (rt2x00dev->bcn != queue ||
410             !test_bit(DRIVER_REQUIRE_BEACON_GUARD, &rt2x00dev->flags))
411                 return 0;
412
413         for (i = 0; i < queue->limit; i++) {
414                 bcn_priv = queue->entries[i].priv_data;
415                 bcn_priv->guardian_urb = usb_alloc_urb(0, GFP_KERNEL);
416                 if (!bcn_priv->guardian_urb)
417                         return -ENOMEM;
418         }
419
420         return 0;
421 }
422
423 static void rt2x00usb_free_urb(struct rt2x00_dev *rt2x00dev,
424                                struct data_queue *queue)
425 {
426         struct queue_entry_priv_usb *entry_priv;
427         struct queue_entry_priv_usb_bcn *bcn_priv;
428         unsigned int i;
429
430         if (!queue->entries)
431                 return;
432
433         for (i = 0; i < queue->limit; i++) {
434                 entry_priv = queue->entries[i].priv_data;
435                 usb_kill_urb(entry_priv->urb);
436                 usb_free_urb(entry_priv->urb);
437         }
438
439         /*
440          * If this is not the beacon queue or
441          * no guardian byte was required for the beacon,
442          * then we are done.
443          */
444         if (rt2x00dev->bcn != queue ||
445             !test_bit(DRIVER_REQUIRE_BEACON_GUARD, &rt2x00dev->flags))
446                 return;
447
448         for (i = 0; i < queue->limit; i++) {
449                 bcn_priv = queue->entries[i].priv_data;
450                 usb_kill_urb(bcn_priv->guardian_urb);
451                 usb_free_urb(bcn_priv->guardian_urb);
452         }
453 }
454
455 int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
456 {
457         struct data_queue *queue;
458         int status;
459
460         /*
461          * Allocate DMA
462          */
463         queue_for_each(rt2x00dev, queue) {
464                 status = rt2x00usb_alloc_urb(rt2x00dev, queue);
465                 if (status)
466                         goto exit;
467         }
468
469         return 0;
470
471 exit:
472         rt2x00usb_uninitialize(rt2x00dev);
473
474         return status;
475 }
476 EXPORT_SYMBOL_GPL(rt2x00usb_initialize);
477
478 void rt2x00usb_uninitialize(struct rt2x00_dev *rt2x00dev)
479 {
480         struct data_queue *queue;
481
482         queue_for_each(rt2x00dev, queue)
483                 rt2x00usb_free_urb(rt2x00dev, queue);
484 }
485 EXPORT_SYMBOL_GPL(rt2x00usb_uninitialize);
486
487 /*
488  * USB driver handlers.
489  */
490 static void rt2x00usb_free_reg(struct rt2x00_dev *rt2x00dev)
491 {
492         kfree(rt2x00dev->rf);
493         rt2x00dev->rf = NULL;
494
495         kfree(rt2x00dev->eeprom);
496         rt2x00dev->eeprom = NULL;
497
498         kfree(rt2x00dev->csr.cache);
499         rt2x00dev->csr.cache = NULL;
500 }
501
502 static int rt2x00usb_alloc_reg(struct rt2x00_dev *rt2x00dev)
503 {
504         rt2x00dev->csr.cache = kzalloc(CSR_CACHE_SIZE, GFP_KERNEL);
505         if (!rt2x00dev->csr.cache)
506                 goto exit;
507
508         rt2x00dev->eeprom = kzalloc(rt2x00dev->ops->eeprom_size, GFP_KERNEL);
509         if (!rt2x00dev->eeprom)
510                 goto exit;
511
512         rt2x00dev->rf = kzalloc(rt2x00dev->ops->rf_size, GFP_KERNEL);
513         if (!rt2x00dev->rf)
514                 goto exit;
515
516         return 0;
517
518 exit:
519         ERROR_PROBE("Failed to allocate registers.\n");
520
521         rt2x00usb_free_reg(rt2x00dev);
522
523         return -ENOMEM;
524 }
525
526 int rt2x00usb_probe(struct usb_interface *usb_intf,
527                     const struct usb_device_id *id)
528 {
529         struct usb_device *usb_dev = interface_to_usbdev(usb_intf);
530         struct rt2x00_ops *ops = (struct rt2x00_ops *)id->driver_info;
531         struct ieee80211_hw *hw;
532         struct rt2x00_dev *rt2x00dev;
533         int retval;
534
535         usb_dev = usb_get_dev(usb_dev);
536
537         hw = ieee80211_alloc_hw(sizeof(struct rt2x00_dev), ops->hw);
538         if (!hw) {
539                 ERROR_PROBE("Failed to allocate hardware.\n");
540                 retval = -ENOMEM;
541                 goto exit_put_device;
542         }
543
544         usb_set_intfdata(usb_intf, hw);
545
546         rt2x00dev = hw->priv;
547         rt2x00dev->dev = &usb_intf->dev;
548         rt2x00dev->ops = ops;
549         rt2x00dev->hw = hw;
550         mutex_init(&rt2x00dev->usb_cache_mutex);
551
552         rt2x00dev->usb_maxpacket =
553             usb_maxpacket(usb_dev, usb_sndbulkpipe(usb_dev, 1), 1);
554         if (!rt2x00dev->usb_maxpacket)
555                 rt2x00dev->usb_maxpacket = 1;
556
557         retval = rt2x00usb_alloc_reg(rt2x00dev);
558         if (retval)
559                 goto exit_free_device;
560
561         retval = rt2x00lib_probe_dev(rt2x00dev);
562         if (retval)
563                 goto exit_free_reg;
564
565         return 0;
566
567 exit_free_reg:
568         rt2x00usb_free_reg(rt2x00dev);
569
570 exit_free_device:
571         ieee80211_free_hw(hw);
572
573 exit_put_device:
574         usb_put_dev(usb_dev);
575
576         usb_set_intfdata(usb_intf, NULL);
577
578         return retval;
579 }
580 EXPORT_SYMBOL_GPL(rt2x00usb_probe);
581
582 void rt2x00usb_disconnect(struct usb_interface *usb_intf)
583 {
584         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
585         struct rt2x00_dev *rt2x00dev = hw->priv;
586
587         /*
588          * Free all allocated data.
589          */
590         rt2x00lib_remove_dev(rt2x00dev);
591         rt2x00usb_free_reg(rt2x00dev);
592         ieee80211_free_hw(hw);
593
594         /*
595          * Free the USB device data.
596          */
597         usb_set_intfdata(usb_intf, NULL);
598         usb_put_dev(interface_to_usbdev(usb_intf));
599 }
600 EXPORT_SYMBOL_GPL(rt2x00usb_disconnect);
601
602 #ifdef CONFIG_PM
603 int rt2x00usb_suspend(struct usb_interface *usb_intf, pm_message_t state)
604 {
605         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
606         struct rt2x00_dev *rt2x00dev = hw->priv;
607         int retval;
608
609         retval = rt2x00lib_suspend(rt2x00dev, state);
610         if (retval)
611                 return retval;
612
613         rt2x00usb_free_reg(rt2x00dev);
614
615         /*
616          * Decrease usbdev refcount.
617          */
618         usb_put_dev(interface_to_usbdev(usb_intf));
619
620         return 0;
621 }
622 EXPORT_SYMBOL_GPL(rt2x00usb_suspend);
623
624 int rt2x00usb_resume(struct usb_interface *usb_intf)
625 {
626         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
627         struct rt2x00_dev *rt2x00dev = hw->priv;
628         int retval;
629
630         usb_get_dev(interface_to_usbdev(usb_intf));
631
632         retval = rt2x00usb_alloc_reg(rt2x00dev);
633         if (retval)
634                 return retval;
635
636         retval = rt2x00lib_resume(rt2x00dev);
637         if (retval)
638                 goto exit_free_reg;
639
640         return 0;
641
642 exit_free_reg:
643         rt2x00usb_free_reg(rt2x00dev);
644
645         return retval;
646 }
647 EXPORT_SYMBOL_GPL(rt2x00usb_resume);
648 #endif /* CONFIG_PM */
649
650 /*
651  * rt2x00usb module information.
652  */
653 MODULE_AUTHOR(DRV_PROJECT);
654 MODULE_VERSION(DRV_VERSION);
655 MODULE_DESCRIPTION("rt2x00 usb library");
656 MODULE_LICENSE("GPL");