Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
[linux-2.6] / drivers / net / wireless / rt2x00 / rt2x00mac.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: rt2x00mac
23         Abstract: rt2x00 generic mac80211 routines.
24  */
25
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28
29 #include "rt2x00.h"
30 #include "rt2x00lib.h"
31
32 static int rt2x00mac_tx_rts_cts(struct rt2x00_dev *rt2x00dev,
33                                 struct data_queue *queue,
34                                 struct sk_buff *frag_skb)
35 {
36         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(frag_skb);
37         struct ieee80211_tx_info *rts_info;
38         struct sk_buff *skb;
39         int size;
40
41         if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
42                 size = sizeof(struct ieee80211_cts);
43         else
44                 size = sizeof(struct ieee80211_rts);
45
46         skb = dev_alloc_skb(size + rt2x00dev->hw->extra_tx_headroom);
47         if (!skb) {
48                 WARNING(rt2x00dev, "Failed to create RTS/CTS frame.\n");
49                 return NETDEV_TX_BUSY;
50         }
51
52         skb_reserve(skb, rt2x00dev->hw->extra_tx_headroom);
53         skb_put(skb, size);
54
55         /*
56          * Copy TX information over from original frame to
57          * RTS/CTS frame. Note that we set the no encryption flag
58          * since we don't want this frame to be encrypted.
59          * RTS frames should be acked, while CTS-to-self frames
60          * should not. The ready for TX flag is cleared to prevent
61          * it being automatically send when the descriptor is
62          * written to the hardware.
63          */
64         memcpy(skb->cb, frag_skb->cb, sizeof(skb->cb));
65         rts_info = IEEE80211_SKB_CB(skb);
66         rts_info->control.hw_key = NULL;
67         rts_info->flags &= ~IEEE80211_TX_CTL_USE_RTS_CTS;
68         rts_info->flags &= ~IEEE80211_TX_CTL_USE_CTS_PROTECT;
69         rts_info->flags &= ~IEEE80211_TX_CTL_REQ_TX_STATUS;
70
71         if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
72                 rts_info->flags |= IEEE80211_TX_CTL_NO_ACK;
73         else
74                 rts_info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
75
76         if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
77                 ieee80211_ctstoself_get(rt2x00dev->hw, tx_info->control.vif,
78                                         frag_skb->data, size, tx_info,
79                                         (struct ieee80211_cts *)(skb->data));
80         else
81                 ieee80211_rts_get(rt2x00dev->hw, tx_info->control.vif,
82                                   frag_skb->data, size, tx_info,
83                                   (struct ieee80211_rts *)(skb->data));
84
85         if (rt2x00queue_write_tx_frame(queue, skb)) {
86                 dev_kfree_skb_any(skb);
87                 WARNING(rt2x00dev, "Failed to send RTS/CTS frame.\n");
88                 return NETDEV_TX_BUSY;
89         }
90
91         return NETDEV_TX_OK;
92 }
93
94 int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
95 {
96         struct rt2x00_dev *rt2x00dev = hw->priv;
97         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
98         struct ieee80211_hdr *ieee80211hdr = (struct ieee80211_hdr *)skb->data;
99         enum data_queue_qid qid = skb_get_queue_mapping(skb);
100         struct data_queue *queue;
101         u16 frame_control;
102
103         /*
104          * Mac80211 might be calling this function while we are trying
105          * to remove the device or perhaps suspending it.
106          * Note that we can only stop the TX queues inside the TX path
107          * due to possible race conditions in mac80211.
108          */
109         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags)) {
110                 ieee80211_stop_queues(hw);
111                 dev_kfree_skb_any(skb);
112                 return NETDEV_TX_OK;
113         }
114
115         /*
116          * Determine which queue to put packet on.
117          */
118         if (tx_info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM &&
119             test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags))
120                 queue = rt2x00queue_get_queue(rt2x00dev, QID_ATIM);
121         else
122                 queue = rt2x00queue_get_queue(rt2x00dev, qid);
123         if (unlikely(!queue)) {
124                 ERROR(rt2x00dev,
125                       "Attempt to send packet over invalid queue %d.\n"
126                       "Please file bug report to %s.\n", qid, DRV_PROJECT);
127                 dev_kfree_skb_any(skb);
128                 return NETDEV_TX_OK;
129         }
130
131         /*
132          * If CTS/RTS is required. create and queue that frame first.
133          * Make sure we have at least enough entries available to send
134          * this CTS/RTS frame as well as the data frame.
135          * Note that when the driver has set the set_rts_threshold()
136          * callback function it doesn't need software generation of
137          * either RTS or CTS-to-self frame and handles everything
138          * inside the hardware.
139          */
140         frame_control = le16_to_cpu(ieee80211hdr->frame_control);
141         if ((tx_info->flags & (IEEE80211_TX_CTL_USE_RTS_CTS |
142                                IEEE80211_TX_CTL_USE_CTS_PROTECT)) &&
143             !rt2x00dev->ops->hw->set_rts_threshold) {
144                 if (rt2x00queue_available(queue) <= 1) {
145                         ieee80211_stop_queue(rt2x00dev->hw, qid);
146                         return NETDEV_TX_BUSY;
147                 }
148
149                 if (rt2x00mac_tx_rts_cts(rt2x00dev, queue, skb)) {
150                         ieee80211_stop_queue(rt2x00dev->hw, qid);
151                         return NETDEV_TX_BUSY;
152                 }
153         }
154
155         if (rt2x00queue_write_tx_frame(queue, skb)) {
156                 ieee80211_stop_queue(rt2x00dev->hw, qid);
157                 return NETDEV_TX_BUSY;
158         }
159
160         if (rt2x00queue_threshold(queue))
161                 ieee80211_stop_queue(rt2x00dev->hw, qid);
162
163         return NETDEV_TX_OK;
164 }
165 EXPORT_SYMBOL_GPL(rt2x00mac_tx);
166
167 int rt2x00mac_start(struct ieee80211_hw *hw)
168 {
169         struct rt2x00_dev *rt2x00dev = hw->priv;
170
171         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
172                 return 0;
173
174         return rt2x00lib_start(rt2x00dev);
175 }
176 EXPORT_SYMBOL_GPL(rt2x00mac_start);
177
178 void rt2x00mac_stop(struct ieee80211_hw *hw)
179 {
180         struct rt2x00_dev *rt2x00dev = hw->priv;
181
182         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
183                 return;
184
185         rt2x00lib_stop(rt2x00dev);
186 }
187 EXPORT_SYMBOL_GPL(rt2x00mac_stop);
188
189 int rt2x00mac_add_interface(struct ieee80211_hw *hw,
190                             struct ieee80211_if_init_conf *conf)
191 {
192         struct rt2x00_dev *rt2x00dev = hw->priv;
193         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
194         struct data_queue *queue = rt2x00queue_get_queue(rt2x00dev, QID_BEACON);
195         struct queue_entry *entry = NULL;
196         unsigned int i;
197
198         /*
199          * Don't allow interfaces to be added
200          * the device has disappeared.
201          */
202         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
203             !test_bit(DEVICE_STARTED, &rt2x00dev->flags))
204                 return -ENODEV;
205
206         switch (conf->type) {
207         case IEEE80211_IF_TYPE_AP:
208                 /*
209                  * We don't support mixed combinations of
210                  * sta and ap interfaces.
211                  */
212                 if (rt2x00dev->intf_sta_count)
213                         return -ENOBUFS;
214
215                 /*
216                  * Check if we exceeded the maximum amount
217                  * of supported interfaces.
218                  */
219                 if (rt2x00dev->intf_ap_count >= rt2x00dev->ops->max_ap_intf)
220                         return -ENOBUFS;
221
222                 break;
223         case IEEE80211_IF_TYPE_STA:
224         case IEEE80211_IF_TYPE_IBSS:
225                 /*
226                  * We don't support mixed combinations of
227                  * sta and ap interfaces.
228                  */
229                 if (rt2x00dev->intf_ap_count)
230                         return -ENOBUFS;
231
232                 /*
233                  * Check if we exceeded the maximum amount
234                  * of supported interfaces.
235                  */
236                 if (rt2x00dev->intf_sta_count >= rt2x00dev->ops->max_sta_intf)
237                         return -ENOBUFS;
238
239                 break;
240         default:
241                 return -EINVAL;
242         }
243
244         /*
245          * Loop through all beacon queues to find a free
246          * entry. Since there are as much beacon entries
247          * as the maximum interfaces, this search shouldn't
248          * fail.
249          */
250         for (i = 0; i < queue->limit; i++) {
251                 entry = &queue->entries[i];
252                 if (!__test_and_set_bit(ENTRY_BCN_ASSIGNED, &entry->flags))
253                         break;
254         }
255
256         if (unlikely(i == queue->limit))
257                 return -ENOBUFS;
258
259         /*
260          * We are now absolutely sure the interface can be created,
261          * increase interface count and start initialization.
262          */
263
264         if (conf->type == IEEE80211_IF_TYPE_AP)
265                 rt2x00dev->intf_ap_count++;
266         else
267                 rt2x00dev->intf_sta_count++;
268
269         spin_lock_init(&intf->lock);
270         spin_lock_init(&intf->seqlock);
271         intf->beacon = entry;
272
273         if (conf->type == IEEE80211_IF_TYPE_AP)
274                 memcpy(&intf->bssid, conf->mac_addr, ETH_ALEN);
275         memcpy(&intf->mac, conf->mac_addr, ETH_ALEN);
276
277         /*
278          * The MAC adddress must be configured after the device
279          * has been initialized. Otherwise the device can reset
280          * the MAC registers.
281          */
282         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, intf->mac, NULL);
283
284         /*
285          * Some filters depend on the current working mode. We can force
286          * an update during the next configure_filter() run by mac80211 by
287          * resetting the current packet_filter state.
288          */
289         rt2x00dev->packet_filter = 0;
290
291         return 0;
292 }
293 EXPORT_SYMBOL_GPL(rt2x00mac_add_interface);
294
295 void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
296                                 struct ieee80211_if_init_conf *conf)
297 {
298         struct rt2x00_dev *rt2x00dev = hw->priv;
299         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
300
301         /*
302          * Don't allow interfaces to be remove while
303          * either the device has disappeared or when
304          * no interface is present.
305          */
306         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
307             (conf->type == IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_ap_count) ||
308             (conf->type != IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_sta_count))
309                 return;
310
311         if (conf->type == IEEE80211_IF_TYPE_AP)
312                 rt2x00dev->intf_ap_count--;
313         else
314                 rt2x00dev->intf_sta_count--;
315
316         /*
317          * Release beacon entry so it is available for
318          * new interfaces again.
319          */
320         __clear_bit(ENTRY_BCN_ASSIGNED, &intf->beacon->flags);
321
322         /*
323          * Make sure the bssid and mac address registers
324          * are cleared to prevent false ACKing of frames.
325          */
326         rt2x00lib_config_intf(rt2x00dev, intf,
327                               IEEE80211_IF_TYPE_INVALID, NULL, NULL);
328 }
329 EXPORT_SYMBOL_GPL(rt2x00mac_remove_interface);
330
331 int rt2x00mac_config(struct ieee80211_hw *hw, struct ieee80211_conf *conf)
332 {
333         struct rt2x00_dev *rt2x00dev = hw->priv;
334         int force_reconfig;
335
336         /*
337          * Mac80211 might be calling this function while we are trying
338          * to remove the device or perhaps suspending it.
339          */
340         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
341                 return 0;
342
343         /*
344          * Check if we need to disable the radio,
345          * if this is not the case, at least the RX must be disabled.
346          */
347         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags)) {
348                 if (!conf->radio_enabled)
349                         rt2x00lib_disable_radio(rt2x00dev);
350                 else
351                         rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_OFF);
352         }
353
354         /*
355          * When the DEVICE_DIRTY_CONFIG flag is set, the device has recently
356          * been started and the configuration must be forced upon the hardware.
357          * Otherwise registers will not be intialized correctly and could
358          * result in non-working hardware because essential registers aren't
359          * initialized.
360          */
361         force_reconfig =
362             __test_and_clear_bit(DEVICE_DIRTY_CONFIG, &rt2x00dev->flags);
363
364         rt2x00lib_config(rt2x00dev, conf, force_reconfig);
365
366         /*
367          * Reenable RX only if the radio should be on.
368          */
369         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags))
370                 rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON);
371         else if (conf->radio_enabled)
372                 return rt2x00lib_enable_radio(rt2x00dev);
373
374         return 0;
375 }
376 EXPORT_SYMBOL_GPL(rt2x00mac_config);
377
378 int rt2x00mac_config_interface(struct ieee80211_hw *hw,
379                                struct ieee80211_vif *vif,
380                                struct ieee80211_if_conf *conf)
381 {
382         struct rt2x00_dev *rt2x00dev = hw->priv;
383         struct rt2x00_intf *intf = vif_to_intf(vif);
384         int update_bssid = 0;
385         int status = 0;
386
387         /*
388          * Mac80211 might be calling this function while we are trying
389          * to remove the device or perhaps suspending it.
390          */
391         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
392                 return 0;
393
394         spin_lock(&intf->lock);
395
396         /*
397          * conf->bssid can be NULL if coming from the internal
398          * beacon update routine.
399          */
400         if (conf->changed & IEEE80211_IFCC_BSSID && conf->bssid) {
401                 update_bssid = 1;
402                 memcpy(&intf->bssid, conf->bssid, ETH_ALEN);
403         }
404
405         spin_unlock(&intf->lock);
406
407         /*
408          * Call rt2x00_config_intf() outside of the spinlock context since
409          * the call will sleep for USB drivers. By using the ieee80211_if_conf
410          * values as arguments we make keep access to rt2x00_intf thread safe
411          * even without the lock.
412          */
413         rt2x00lib_config_intf(rt2x00dev, intf, vif->type, NULL,
414                               update_bssid ? conf->bssid : NULL);
415
416         /*
417          * Update the beacon.
418          */
419         if (conf->changed & IEEE80211_IFCC_BEACON)
420                 status = rt2x00queue_update_beacon(rt2x00dev, vif);
421
422         return status;
423 }
424 EXPORT_SYMBOL_GPL(rt2x00mac_config_interface);
425
426 void rt2x00mac_configure_filter(struct ieee80211_hw *hw,
427                                 unsigned int changed_flags,
428                                 unsigned int *total_flags,
429                                 int mc_count, struct dev_addr_list *mc_list)
430 {
431         struct rt2x00_dev *rt2x00dev = hw->priv;
432
433         /*
434          * Mask off any flags we are going to ignore
435          * from the total_flags field.
436          */
437         *total_flags &=
438             FIF_ALLMULTI |
439             FIF_FCSFAIL |
440             FIF_PLCPFAIL |
441             FIF_CONTROL |
442             FIF_OTHER_BSS |
443             FIF_PROMISC_IN_BSS;
444
445         /*
446          * Apply some rules to the filters:
447          * - Some filters imply different filters to be set.
448          * - Some things we can't filter out at all.
449          * - Multicast filter seems to kill broadcast traffic so never use it.
450          */
451         *total_flags |= FIF_ALLMULTI;
452         if (*total_flags & FIF_OTHER_BSS ||
453             *total_flags & FIF_PROMISC_IN_BSS)
454                 *total_flags |= FIF_PROMISC_IN_BSS | FIF_OTHER_BSS;
455
456         /*
457          * Check if there is any work left for us.
458          */
459         if (rt2x00dev->packet_filter == *total_flags)
460                 return;
461         rt2x00dev->packet_filter = *total_flags;
462
463         if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
464                 rt2x00dev->ops->lib->config_filter(rt2x00dev, *total_flags);
465         else
466                 queue_work(rt2x00dev->hw->workqueue, &rt2x00dev->filter_work);
467 }
468 EXPORT_SYMBOL_GPL(rt2x00mac_configure_filter);
469
470 int rt2x00mac_get_stats(struct ieee80211_hw *hw,
471                         struct ieee80211_low_level_stats *stats)
472 {
473         struct rt2x00_dev *rt2x00dev = hw->priv;
474
475         /*
476          * The dot11ACKFailureCount, dot11RTSFailureCount and
477          * dot11RTSSuccessCount are updated in interrupt time.
478          * dot11FCSErrorCount is updated in the link tuner.
479          */
480         memcpy(stats, &rt2x00dev->low_level_stats, sizeof(*stats));
481
482         return 0;
483 }
484 EXPORT_SYMBOL_GPL(rt2x00mac_get_stats);
485
486 int rt2x00mac_get_tx_stats(struct ieee80211_hw *hw,
487                            struct ieee80211_tx_queue_stats *stats)
488 {
489         struct rt2x00_dev *rt2x00dev = hw->priv;
490         unsigned int i;
491
492         for (i = 0; i < rt2x00dev->ops->tx_queues; i++) {
493                 stats[i].len = rt2x00dev->tx[i].length;
494                 stats[i].limit = rt2x00dev->tx[i].limit;
495                 stats[i].count = rt2x00dev->tx[i].count;
496         }
497
498         return 0;
499 }
500 EXPORT_SYMBOL_GPL(rt2x00mac_get_tx_stats);
501
502 void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
503                                 struct ieee80211_vif *vif,
504                                 struct ieee80211_bss_conf *bss_conf,
505                                 u32 changes)
506 {
507         struct rt2x00_dev *rt2x00dev = hw->priv;
508         struct rt2x00_intf *intf = vif_to_intf(vif);
509         unsigned int delayed = 0;
510
511         /*
512          * When the association status has changed we must reset the link
513          * tuner counter. This is because some drivers determine if they
514          * should perform link tuning based on the number of seconds
515          * while associated or not associated.
516          */
517         if (changes & BSS_CHANGED_ASSOC) {
518                 rt2x00dev->link.count = 0;
519
520                 if (bss_conf->assoc)
521                         rt2x00dev->intf_associated++;
522                 else
523                         rt2x00dev->intf_associated--;
524
525                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
526                         rt2x00leds_led_assoc(rt2x00dev,
527                                              !!rt2x00dev->intf_associated);
528                 else
529                         delayed |= DELAYED_LED_ASSOC;
530         }
531
532         /*
533          * When the erp information has changed, we should perform
534          * additional configuration steps. For all other changes we are done.
535          */
536         if (changes & (BSS_CHANGED_ERP_PREAMBLE | BSS_CHANGED_ERP_CTS_PROT)) {
537                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
538                         rt2x00lib_config_erp(rt2x00dev, intf, bss_conf);
539                 else
540                         delayed |= DELAYED_CONFIG_ERP;
541         }
542
543         spin_lock(&intf->lock);
544         memcpy(&intf->conf, bss_conf, sizeof(*bss_conf));
545         if (delayed) {
546                 intf->delayed_flags |= delayed;
547                 schedule_work(&rt2x00dev->intf_work);
548         }
549         spin_unlock(&intf->lock);
550 }
551 EXPORT_SYMBOL_GPL(rt2x00mac_bss_info_changed);
552
553 int rt2x00mac_conf_tx(struct ieee80211_hw *hw, u16 queue_idx,
554                       const struct ieee80211_tx_queue_params *params)
555 {
556         struct rt2x00_dev *rt2x00dev = hw->priv;
557         struct data_queue *queue;
558
559         queue = rt2x00queue_get_queue(rt2x00dev, queue_idx);
560         if (unlikely(!queue))
561                 return -EINVAL;
562
563         /*
564          * The passed variables are stored as real value ((2^n)-1).
565          * Ralink registers require to know the bit number 'n'.
566          */
567         if (params->cw_min > 0)
568                 queue->cw_min = fls(params->cw_min);
569         else
570                 queue->cw_min = 5; /* cw_min: 2^5 = 32. */
571
572         if (params->cw_max > 0)
573                 queue->cw_max = fls(params->cw_max);
574         else
575                 queue->cw_max = 10; /* cw_min: 2^10 = 1024. */
576
577         queue->aifs = params->aifs;
578
579         INFO(rt2x00dev,
580              "Configured TX queue %d - CWmin: %d, CWmax: %d, Aifs: %d.\n",
581              queue_idx, queue->cw_min, queue->cw_max, queue->aifs);
582
583         return 0;
584 }
585 EXPORT_SYMBOL_GPL(rt2x00mac_conf_tx);