Merge commit 'gcl/gcl-next'
[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                                 struct ieee80211_tx_control *control)
36 {
37         struct skb_frame_desc *skbdesc;
38         struct sk_buff *skb;
39         int size;
40
41         if (control->flags & IEEE80211_TXCTL_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         if (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
56                 ieee80211_ctstoself_get(rt2x00dev->hw, control->vif,
57                                         frag_skb->data, frag_skb->len, control,
58                                         (struct ieee80211_cts *)(skb->data));
59         else
60                 ieee80211_rts_get(rt2x00dev->hw, control->vif,
61                                   frag_skb->data, frag_skb->len, control,
62                                   (struct ieee80211_rts *)(skb->data));
63
64         /*
65          * Initialize skb descriptor
66          */
67         skbdesc = get_skb_frame_desc(skb);
68         memset(skbdesc, 0, sizeof(*skbdesc));
69         skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
70
71         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb, control)) {
72                 WARNING(rt2x00dev, "Failed to send RTS/CTS frame.\n");
73                 return NETDEV_TX_BUSY;
74         }
75
76         return NETDEV_TX_OK;
77 }
78
79 int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb,
80                  struct ieee80211_tx_control *control)
81 {
82         struct rt2x00_dev *rt2x00dev = hw->priv;
83         struct ieee80211_hdr *ieee80211hdr = (struct ieee80211_hdr *)skb->data;
84         struct data_queue *queue;
85         struct skb_frame_desc *skbdesc;
86         u16 frame_control;
87
88         /*
89          * Mac80211 might be calling this function while we are trying
90          * to remove the device or perhaps suspending it.
91          * Note that we can only stop the TX queues inside the TX path
92          * due to possible race conditions in mac80211.
93          */
94         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags)) {
95                 ieee80211_stop_queues(hw);
96                 dev_kfree_skb_any(skb);
97                 return NETDEV_TX_OK;
98         }
99
100         /*
101          * Determine which queue to put packet on.
102          */
103         if (control->flags & IEEE80211_TXCTL_SEND_AFTER_DTIM &&
104             test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags))
105                 queue = rt2x00queue_get_queue(rt2x00dev, RT2X00_BCN_QUEUE_ATIM);
106         else
107                 queue = rt2x00queue_get_queue(rt2x00dev, control->queue);
108         if (unlikely(!queue)) {
109                 ERROR(rt2x00dev,
110                       "Attempt to send packet over invalid queue %d.\n"
111                       "Please file bug report to %s.\n",
112                       control->queue, DRV_PROJECT);
113                 dev_kfree_skb_any(skb);
114                 return NETDEV_TX_OK;
115         }
116
117         /*
118          * If CTS/RTS is required. and this frame is not CTS or RTS,
119          * create and queue that frame first. But make sure we have
120          * at least enough entries available to send this CTS/RTS
121          * frame as well as the data frame.
122          */
123         frame_control = le16_to_cpu(ieee80211hdr->frame_control);
124         if (!is_rts_frame(frame_control) && !is_cts_frame(frame_control) &&
125             (control->flags & (IEEE80211_TXCTL_USE_RTS_CTS |
126                                IEEE80211_TXCTL_USE_CTS_PROTECT))) {
127                 if (rt2x00queue_available(queue) <= 1) {
128                         ieee80211_stop_queue(rt2x00dev->hw, control->queue);
129                         return NETDEV_TX_BUSY;
130                 }
131
132                 if (rt2x00mac_tx_rts_cts(rt2x00dev, queue, skb, control)) {
133                         ieee80211_stop_queue(rt2x00dev->hw, control->queue);
134                         return NETDEV_TX_BUSY;
135                 }
136         }
137
138         /*
139          * Initialize skb descriptor
140          */
141         skbdesc = get_skb_frame_desc(skb);
142         memset(skbdesc, 0, sizeof(*skbdesc));
143
144         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb, control)) {
145                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
146                 return NETDEV_TX_BUSY;
147         }
148
149         if (rt2x00queue_full(queue))
150                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
151
152         if (rt2x00dev->ops->lib->kick_tx_queue)
153                 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, control->queue);
154
155         return NETDEV_TX_OK;
156 }
157 EXPORT_SYMBOL_GPL(rt2x00mac_tx);
158
159 int rt2x00mac_start(struct ieee80211_hw *hw)
160 {
161         struct rt2x00_dev *rt2x00dev = hw->priv;
162
163         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
164                 return 0;
165
166         return rt2x00lib_start(rt2x00dev);
167 }
168 EXPORT_SYMBOL_GPL(rt2x00mac_start);
169
170 void rt2x00mac_stop(struct ieee80211_hw *hw)
171 {
172         struct rt2x00_dev *rt2x00dev = hw->priv;
173
174         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
175                 return;
176
177         rt2x00lib_stop(rt2x00dev);
178 }
179 EXPORT_SYMBOL_GPL(rt2x00mac_stop);
180
181 int rt2x00mac_add_interface(struct ieee80211_hw *hw,
182                             struct ieee80211_if_init_conf *conf)
183 {
184         struct rt2x00_dev *rt2x00dev = hw->priv;
185         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
186         struct data_queue *queue =
187             rt2x00queue_get_queue(rt2x00dev, RT2X00_BCN_QUEUE_BEACON);
188         struct queue_entry *entry = NULL;
189         unsigned int i;
190
191         /*
192          * Don't allow interfaces to be added
193          * the device has disappeared.
194          */
195         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
196             !test_bit(DEVICE_STARTED, &rt2x00dev->flags))
197                 return -ENODEV;
198
199         /*
200          * When we don't support mixed interfaces (a combination
201          * of sta and ap virtual interfaces) then we can only
202          * add this interface when the rival interface count is 0.
203          */
204         if (!test_bit(DRIVER_SUPPORT_MIXED_INTERFACES, &rt2x00dev->flags) &&
205             ((conf->type == IEEE80211_IF_TYPE_AP && rt2x00dev->intf_sta_count) ||
206              (conf->type != IEEE80211_IF_TYPE_AP && rt2x00dev->intf_ap_count)))
207                 return -ENOBUFS;
208
209         /*
210          * Check if we exceeded the maximum amount of supported interfaces.
211          */
212         if ((conf->type == IEEE80211_IF_TYPE_AP &&
213              rt2x00dev->intf_ap_count >= rt2x00dev->ops->max_ap_intf) ||
214             (conf->type != IEEE80211_IF_TYPE_AP &&
215              rt2x00dev->intf_sta_count >= rt2x00dev->ops->max_sta_intf))
216                 return -ENOBUFS;
217
218         /*
219          * Loop through all beacon queues to find a free
220          * entry. Since there are as much beacon entries
221          * as the maximum interfaces, this search shouldn't
222          * fail.
223          */
224         for (i = 0; i < queue->limit; i++) {
225                 entry = &queue->entries[i];
226                 if (!__test_and_set_bit(ENTRY_BCN_ASSIGNED, &entry->flags))
227                         break;
228         }
229
230         if (unlikely(i == queue->limit))
231                 return -ENOBUFS;
232
233         /*
234          * We are now absolutely sure the interface can be created,
235          * increase interface count and start initialization.
236          */
237
238         if (conf->type == IEEE80211_IF_TYPE_AP)
239                 rt2x00dev->intf_ap_count++;
240         else
241                 rt2x00dev->intf_sta_count++;
242
243         spin_lock_init(&intf->lock);
244         intf->beacon = entry;
245
246         if (conf->type == IEEE80211_IF_TYPE_AP)
247                 memcpy(&intf->bssid, conf->mac_addr, ETH_ALEN);
248         memcpy(&intf->mac, conf->mac_addr, ETH_ALEN);
249
250         /*
251          * The MAC adddress must be configured after the device
252          * has been initialized. Otherwise the device can reset
253          * the MAC registers.
254          */
255         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, intf->mac, NULL);
256
257         /*
258          * Some filters depend on the current working mode. We can force
259          * an update during the next configure_filter() run by mac80211 by
260          * resetting the current packet_filter state.
261          */
262         rt2x00dev->packet_filter = 0;
263
264         return 0;
265 }
266 EXPORT_SYMBOL_GPL(rt2x00mac_add_interface);
267
268 void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
269                                 struct ieee80211_if_init_conf *conf)
270 {
271         struct rt2x00_dev *rt2x00dev = hw->priv;
272         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
273
274         /*
275          * Don't allow interfaces to be remove while
276          * either the device has disappeared or when
277          * no interface is present.
278          */
279         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
280             (conf->type == IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_ap_count) ||
281             (conf->type != IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_sta_count))
282                 return;
283
284         if (conf->type == IEEE80211_IF_TYPE_AP)
285                 rt2x00dev->intf_ap_count--;
286         else
287                 rt2x00dev->intf_sta_count--;
288
289         /*
290          * Release beacon entry so it is available for
291          * new interfaces again.
292          */
293         __clear_bit(ENTRY_BCN_ASSIGNED, &intf->beacon->flags);
294
295         /*
296          * Make sure the bssid and mac address registers
297          * are cleared to prevent false ACKing of frames.
298          */
299         rt2x00lib_config_intf(rt2x00dev, intf,
300                               IEEE80211_IF_TYPE_INVALID, NULL, NULL);
301 }
302 EXPORT_SYMBOL_GPL(rt2x00mac_remove_interface);
303
304 int rt2x00mac_config(struct ieee80211_hw *hw, struct ieee80211_conf *conf)
305 {
306         struct rt2x00_dev *rt2x00dev = hw->priv;
307
308         /*
309          * Mac80211 might be calling this function while we are trying
310          * to remove the device or perhaps suspending it.
311          */
312         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
313                 return 0;
314
315         /*
316          * Check if we need to disable the radio,
317          * if this is not the case, at least the RX must be disabled.
318          */
319         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags)) {
320                 if (!conf->radio_enabled)
321                         rt2x00lib_disable_radio(rt2x00dev);
322                 else
323                         rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_OFF);
324         }
325
326         rt2x00lib_config(rt2x00dev, conf, 0);
327
328         /*
329          * Reenable RX only if the radio should be on.
330          */
331         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags))
332                 rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON);
333         else if (conf->radio_enabled)
334                 return rt2x00lib_enable_radio(rt2x00dev);
335
336         return 0;
337 }
338 EXPORT_SYMBOL_GPL(rt2x00mac_config);
339
340 int rt2x00mac_config_interface(struct ieee80211_hw *hw,
341                                struct ieee80211_vif *vif,
342                                struct ieee80211_if_conf *conf)
343 {
344         struct rt2x00_dev *rt2x00dev = hw->priv;
345         struct rt2x00_intf *intf = vif_to_intf(vif);
346         int status;
347
348         /*
349          * Mac80211 might be calling this function while we are trying
350          * to remove the device or perhaps suspending it.
351          */
352         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
353                 return 0;
354
355         spin_lock(&intf->lock);
356
357         /*
358          * If the interface does not work in master mode,
359          * then the bssid value in the interface structure
360          * should now be set.
361          */
362         if (conf->type != IEEE80211_IF_TYPE_AP)
363                 memcpy(&intf->bssid, conf->bssid, ETH_ALEN);
364
365         spin_unlock(&intf->lock);
366
367         /*
368          * Call rt2x00_config_intf() outside of the spinlock context since
369          * the call will sleep for USB drivers. By using the ieee80211_if_conf
370          * values as arguments we make keep access to rt2x00_intf thread safe
371          * even without the lock.
372          */
373         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, NULL, conf->bssid);
374
375         /*
376          * We only need to initialize the beacon when master mode is enabled.
377          */
378         if (conf->type != IEEE80211_IF_TYPE_AP || !conf->beacon)
379                 return 0;
380
381         status = rt2x00dev->ops->hw->beacon_update(rt2x00dev->hw,
382                                                    conf->beacon,
383                                                    conf->beacon_control);
384         if (status)
385                 dev_kfree_skb(conf->beacon);
386
387         return status;
388 }
389 EXPORT_SYMBOL_GPL(rt2x00mac_config_interface);
390
391 void rt2x00mac_configure_filter(struct ieee80211_hw *hw,
392                                 unsigned int changed_flags,
393                                 unsigned int *total_flags,
394                                 int mc_count, struct dev_addr_list *mc_list)
395 {
396         struct rt2x00_dev *rt2x00dev = hw->priv;
397
398         /*
399          * Mask off any flags we are going to ignore
400          * from the total_flags field.
401          */
402         *total_flags &=
403             FIF_ALLMULTI |
404             FIF_FCSFAIL |
405             FIF_PLCPFAIL |
406             FIF_CONTROL |
407             FIF_OTHER_BSS |
408             FIF_PROMISC_IN_BSS;
409
410         /*
411          * Apply some rules to the filters:
412          * - Some filters imply different filters to be set.
413          * - Some things we can't filter out at all.
414          * - Multicast filter seems to kill broadcast traffic so never use it.
415          */
416         *total_flags |= FIF_ALLMULTI;
417         if (*total_flags & FIF_OTHER_BSS ||
418             *total_flags & FIF_PROMISC_IN_BSS)
419                 *total_flags |= FIF_PROMISC_IN_BSS | FIF_OTHER_BSS;
420
421         /*
422          * Check if there is any work left for us.
423          */
424         if (rt2x00dev->packet_filter == *total_flags)
425                 return;
426         rt2x00dev->packet_filter = *total_flags;
427
428         if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
429                 rt2x00dev->ops->lib->config_filter(rt2x00dev, *total_flags);
430         else
431                 queue_work(rt2x00dev->workqueue, &rt2x00dev->filter_work);
432 }
433 EXPORT_SYMBOL_GPL(rt2x00mac_configure_filter);
434
435 int rt2x00mac_get_stats(struct ieee80211_hw *hw,
436                         struct ieee80211_low_level_stats *stats)
437 {
438         struct rt2x00_dev *rt2x00dev = hw->priv;
439
440         /*
441          * The dot11ACKFailureCount, dot11RTSFailureCount and
442          * dot11RTSSuccessCount are updated in interrupt time.
443          * dot11FCSErrorCount is updated in the link tuner.
444          */
445         memcpy(stats, &rt2x00dev->low_level_stats, sizeof(*stats));
446
447         return 0;
448 }
449 EXPORT_SYMBOL_GPL(rt2x00mac_get_stats);
450
451 int rt2x00mac_get_tx_stats(struct ieee80211_hw *hw,
452                            struct ieee80211_tx_queue_stats *stats)
453 {
454         struct rt2x00_dev *rt2x00dev = hw->priv;
455         unsigned int i;
456
457         for (i = 0; i < hw->queues; i++) {
458                 stats->data[i].len = rt2x00dev->tx[i].length;
459                 stats->data[i].limit = rt2x00dev->tx[i].limit;
460                 stats->data[i].count = rt2x00dev->tx[i].count;
461         }
462
463         return 0;
464 }
465 EXPORT_SYMBOL_GPL(rt2x00mac_get_tx_stats);
466
467 void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
468                                 struct ieee80211_vif *vif,
469                                 struct ieee80211_bss_conf *bss_conf,
470                                 u32 changes)
471 {
472         struct rt2x00_dev *rt2x00dev = hw->priv;
473         struct rt2x00_intf *intf = vif_to_intf(vif);
474         unsigned int delayed = 0;
475
476         /*
477          * When the association status has changed we must reset the link
478          * tuner counter. This is because some drivers determine if they
479          * should perform link tuning based on the number of seconds
480          * while associated or not associated.
481          */
482         if (changes & BSS_CHANGED_ASSOC) {
483                 rt2x00dev->link.count = 0;
484
485                 if (bss_conf->assoc)
486                         rt2x00dev->intf_associated++;
487                 else
488                         rt2x00dev->intf_associated--;
489
490                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
491                         rt2x00leds_led_assoc(rt2x00dev,
492                                              !!rt2x00dev->intf_associated);
493                 else
494                         delayed |= DELAYED_LED_ASSOC;
495         }
496
497         /*
498          * When the erp information has changed, we should perform
499          * additional configuration steps. For all other changes we are done.
500          */
501         if (changes & BSS_CHANGED_ERP_PREAMBLE) {
502                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
503                         rt2x00lib_config_erp(rt2x00dev, intf, bss_conf);
504                 else
505                         delayed |= DELAYED_CONFIG_ERP;
506         }
507
508         spin_lock(&intf->lock);
509         memcpy(&intf->conf, bss_conf, sizeof(*bss_conf));
510         if (delayed) {
511                 intf->delayed_flags |= delayed;
512                 queue_work(rt2x00dev->workqueue, &rt2x00dev->intf_work);
513         }
514         spin_unlock(&intf->lock);
515 }
516 EXPORT_SYMBOL_GPL(rt2x00mac_bss_info_changed);
517
518 int rt2x00mac_conf_tx(struct ieee80211_hw *hw, int queue_idx,
519                       const struct ieee80211_tx_queue_params *params)
520 {
521         struct rt2x00_dev *rt2x00dev = hw->priv;
522         struct data_queue *queue;
523
524         queue = rt2x00queue_get_queue(rt2x00dev, queue_idx);
525         if (unlikely(!queue))
526                 return -EINVAL;
527
528         /*
529          * The passed variables are stored as real value ((2^n)-1).
530          * Ralink registers require to know the bit number 'n'.
531          */
532         if (params->cw_min > 0)
533                 queue->cw_min = fls(params->cw_min);
534         else
535                 queue->cw_min = 5; /* cw_min: 2^5 = 32. */
536
537         if (params->cw_max > 0)
538                 queue->cw_max = fls(params->cw_max);
539         else
540                 queue->cw_max = 10; /* cw_min: 2^10 = 1024. */
541
542         if (params->aifs >= 0)
543                 queue->aifs = params->aifs;
544         else
545                 queue->aifs = 2;
546
547         INFO(rt2x00dev,
548              "Configured TX queue %d - CWmin: %d, CWmax: %d, Aifs: %d.\n",
549              queue_idx, queue->cw_min, queue->cw_max, queue->aifs);
550
551         return 0;
552 }
553 EXPORT_SYMBOL_GPL(rt2x00mac_conf_tx);