usb/ps3: Add missing annotations
[pandora-kernel.git] / drivers / net / wireless / ath9k / virtual.c
1 /*
2  * Copyright (c) 2008-2009 Atheros Communications Inc.
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16
17 #include "ath9k.h"
18
19 struct ath9k_vif_iter_data {
20         int count;
21         u8 *addr;
22 };
23
24 static void ath9k_vif_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
25 {
26         struct ath9k_vif_iter_data *iter_data = data;
27         u8 *nbuf;
28
29         nbuf = krealloc(iter_data->addr, (iter_data->count + 1) * ETH_ALEN,
30                         GFP_ATOMIC);
31         if (nbuf == NULL)
32                 return;
33
34         memcpy(nbuf + iter_data->count * ETH_ALEN, mac, ETH_ALEN);
35         iter_data->addr = nbuf;
36         iter_data->count++;
37 }
38
39 void ath9k_set_bssid_mask(struct ieee80211_hw *hw)
40 {
41         struct ath_wiphy *aphy = hw->priv;
42         struct ath_softc *sc = aphy->sc;
43         struct ath9k_vif_iter_data iter_data;
44         int i, j;
45         u8 mask[ETH_ALEN];
46
47         /*
48          * Add primary MAC address even if it is not in active use since it
49          * will be configured to the hardware as the starting point and the
50          * BSSID mask will need to be changed if another address is active.
51          */
52         iter_data.addr = kmalloc(ETH_ALEN, GFP_ATOMIC);
53         if (iter_data.addr) {
54                 memcpy(iter_data.addr, sc->sc_ah->macaddr, ETH_ALEN);
55                 iter_data.count = 1;
56         } else
57                 iter_data.count = 0;
58
59         /* Get list of all active MAC addresses */
60         spin_lock_bh(&sc->wiphy_lock);
61         ieee80211_iterate_active_interfaces_atomic(sc->hw, ath9k_vif_iter,
62                                                    &iter_data);
63         for (i = 0; i < sc->num_sec_wiphy; i++) {
64                 if (sc->sec_wiphy[i] == NULL)
65                         continue;
66                 ieee80211_iterate_active_interfaces_atomic(
67                         sc->sec_wiphy[i]->hw, ath9k_vif_iter, &iter_data);
68         }
69         spin_unlock_bh(&sc->wiphy_lock);
70
71         /* Generate an address mask to cover all active addresses */
72         memset(mask, 0, ETH_ALEN);
73         for (i = 0; i < iter_data.count; i++) {
74                 u8 *a1 = iter_data.addr + i * ETH_ALEN;
75                 for (j = i + 1; j < iter_data.count; j++) {
76                         u8 *a2 = iter_data.addr + j * ETH_ALEN;
77                         mask[0] |= a1[0] ^ a2[0];
78                         mask[1] |= a1[1] ^ a2[1];
79                         mask[2] |= a1[2] ^ a2[2];
80                         mask[3] |= a1[3] ^ a2[3];
81                         mask[4] |= a1[4] ^ a2[4];
82                         mask[5] |= a1[5] ^ a2[5];
83                 }
84         }
85
86         kfree(iter_data.addr);
87
88         /* Invert the mask and configure hardware */
89         sc->bssidmask[0] = ~mask[0];
90         sc->bssidmask[1] = ~mask[1];
91         sc->bssidmask[2] = ~mask[2];
92         sc->bssidmask[3] = ~mask[3];
93         sc->bssidmask[4] = ~mask[4];
94         sc->bssidmask[5] = ~mask[5];
95
96         ath9k_hw_setbssidmask(sc);
97 }
98
99 int ath9k_wiphy_add(struct ath_softc *sc)
100 {
101         int i, error;
102         struct ath_wiphy *aphy;
103         struct ieee80211_hw *hw;
104         u8 addr[ETH_ALEN];
105
106         hw = ieee80211_alloc_hw(sizeof(struct ath_wiphy), &ath9k_ops);
107         if (hw == NULL)
108                 return -ENOMEM;
109
110         spin_lock_bh(&sc->wiphy_lock);
111         for (i = 0; i < sc->num_sec_wiphy; i++) {
112                 if (sc->sec_wiphy[i] == NULL)
113                         break;
114         }
115
116         if (i == sc->num_sec_wiphy) {
117                 /* No empty slot available; increase array length */
118                 struct ath_wiphy **n;
119                 n = krealloc(sc->sec_wiphy,
120                              (sc->num_sec_wiphy + 1) *
121                              sizeof(struct ath_wiphy *),
122                              GFP_ATOMIC);
123                 if (n == NULL) {
124                         spin_unlock_bh(&sc->wiphy_lock);
125                         ieee80211_free_hw(hw);
126                         return -ENOMEM;
127                 }
128                 n[i] = NULL;
129                 sc->sec_wiphy = n;
130                 sc->num_sec_wiphy++;
131         }
132
133         SET_IEEE80211_DEV(hw, sc->dev);
134
135         aphy = hw->priv;
136         aphy->sc = sc;
137         aphy->hw = hw;
138         sc->sec_wiphy[i] = aphy;
139         spin_unlock_bh(&sc->wiphy_lock);
140
141         memcpy(addr, sc->sc_ah->macaddr, ETH_ALEN);
142         addr[0] |= 0x02; /* Locally managed address */
143         /*
144          * XOR virtual wiphy index into the least significant bits to generate
145          * a different MAC address for each virtual wiphy.
146          */
147         addr[5] ^= i & 0xff;
148         addr[4] ^= (i & 0xff00) >> 8;
149         addr[3] ^= (i & 0xff0000) >> 16;
150
151         SET_IEEE80211_PERM_ADDR(hw, addr);
152
153         ath_set_hw_capab(sc, hw);
154
155         error = ieee80211_register_hw(hw);
156
157         if (error == 0) {
158                 /* Make sure wiphy scheduler is started (if enabled) */
159                 ath9k_wiphy_set_scheduler(sc, sc->wiphy_scheduler_int);
160         }
161
162         return error;
163 }
164
165 int ath9k_wiphy_del(struct ath_wiphy *aphy)
166 {
167         struct ath_softc *sc = aphy->sc;
168         int i;
169
170         spin_lock_bh(&sc->wiphy_lock);
171         for (i = 0; i < sc->num_sec_wiphy; i++) {
172                 if (aphy == sc->sec_wiphy[i]) {
173                         sc->sec_wiphy[i] = NULL;
174                         spin_unlock_bh(&sc->wiphy_lock);
175                         ieee80211_unregister_hw(aphy->hw);
176                         ieee80211_free_hw(aphy->hw);
177                         return 0;
178                 }
179         }
180         spin_unlock_bh(&sc->wiphy_lock);
181         return -ENOENT;
182 }
183
184 static int ath9k_send_nullfunc(struct ath_wiphy *aphy,
185                                struct ieee80211_vif *vif, const u8 *bssid,
186                                int ps)
187 {
188         struct ath_softc *sc = aphy->sc;
189         struct ath_tx_control txctl;
190         struct sk_buff *skb;
191         struct ieee80211_hdr *hdr;
192         __le16 fc;
193         struct ieee80211_tx_info *info;
194
195         skb = dev_alloc_skb(24);
196         if (skb == NULL)
197                 return -ENOMEM;
198         hdr = (struct ieee80211_hdr *) skb_put(skb, 24);
199         memset(hdr, 0, 24);
200         fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC |
201                          IEEE80211_FCTL_TODS);
202         if (ps)
203                 fc |= cpu_to_le16(IEEE80211_FCTL_PM);
204         hdr->frame_control = fc;
205         memcpy(hdr->addr1, bssid, ETH_ALEN);
206         memcpy(hdr->addr2, aphy->hw->wiphy->perm_addr, ETH_ALEN);
207         memcpy(hdr->addr3, bssid, ETH_ALEN);
208
209         info = IEEE80211_SKB_CB(skb);
210         memset(info, 0, sizeof(*info));
211         info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS;
212         info->control.vif = vif;
213         info->control.rates[0].idx = 0;
214         info->control.rates[0].count = 4;
215         info->control.rates[1].idx = -1;
216
217         memset(&txctl, 0, sizeof(struct ath_tx_control));
218         txctl.txq = &sc->tx.txq[sc->tx.hwq_map[ATH9K_WME_AC_VO]];
219         txctl.frame_type = ps ? ATH9K_INT_PAUSE : ATH9K_INT_UNPAUSE;
220
221         if (ath_tx_start(aphy->hw, skb, &txctl) != 0)
222                 goto exit;
223
224         return 0;
225 exit:
226         dev_kfree_skb_any(skb);
227         return -1;
228 }
229
230 static bool __ath9k_wiphy_pausing(struct ath_softc *sc)
231 {
232         int i;
233         if (sc->pri_wiphy->state == ATH_WIPHY_PAUSING)
234                 return true;
235         for (i = 0; i < sc->num_sec_wiphy; i++) {
236                 if (sc->sec_wiphy[i] &&
237                     sc->sec_wiphy[i]->state == ATH_WIPHY_PAUSING)
238                         return true;
239         }
240         return false;
241 }
242
243 static bool ath9k_wiphy_pausing(struct ath_softc *sc)
244 {
245         bool ret;
246         spin_lock_bh(&sc->wiphy_lock);
247         ret = __ath9k_wiphy_pausing(sc);
248         spin_unlock_bh(&sc->wiphy_lock);
249         return ret;
250 }
251
252 static bool __ath9k_wiphy_scanning(struct ath_softc *sc)
253 {
254         int i;
255         if (sc->pri_wiphy->state == ATH_WIPHY_SCAN)
256                 return true;
257         for (i = 0; i < sc->num_sec_wiphy; i++) {
258                 if (sc->sec_wiphy[i] &&
259                     sc->sec_wiphy[i]->state == ATH_WIPHY_SCAN)
260                         return true;
261         }
262         return false;
263 }
264
265 bool ath9k_wiphy_scanning(struct ath_softc *sc)
266 {
267         bool ret;
268         spin_lock_bh(&sc->wiphy_lock);
269         ret = __ath9k_wiphy_scanning(sc);
270         spin_unlock_bh(&sc->wiphy_lock);
271         return ret;
272 }
273
274 static int __ath9k_wiphy_unpause(struct ath_wiphy *aphy);
275
276 /* caller must hold wiphy_lock */
277 static void __ath9k_wiphy_unpause_ch(struct ath_wiphy *aphy)
278 {
279         if (aphy == NULL)
280                 return;
281         if (aphy->chan_idx != aphy->sc->chan_idx)
282                 return; /* wiphy not on the selected channel */
283         __ath9k_wiphy_unpause(aphy);
284 }
285
286 static void ath9k_wiphy_unpause_channel(struct ath_softc *sc)
287 {
288         int i;
289         spin_lock_bh(&sc->wiphy_lock);
290         __ath9k_wiphy_unpause_ch(sc->pri_wiphy);
291         for (i = 0; i < sc->num_sec_wiphy; i++)
292                 __ath9k_wiphy_unpause_ch(sc->sec_wiphy[i]);
293         spin_unlock_bh(&sc->wiphy_lock);
294 }
295
296 void ath9k_wiphy_chan_work(struct work_struct *work)
297 {
298         struct ath_softc *sc = container_of(work, struct ath_softc, chan_work);
299         struct ath_wiphy *aphy = sc->next_wiphy;
300
301         if (aphy == NULL)
302                 return;
303
304         /*
305          * All pending interfaces paused; ready to change
306          * channels.
307          */
308
309         /* Change channels */
310         mutex_lock(&sc->mutex);
311         /* XXX: remove me eventually */
312         ath9k_update_ichannel(sc, aphy->hw,
313                               &sc->sc_ah->channels[sc->chan_idx]);
314         ath_update_chainmask(sc, sc->chan_is_ht);
315         if (ath_set_channel(sc, aphy->hw,
316                             &sc->sc_ah->channels[sc->chan_idx]) < 0) {
317                 printk(KERN_DEBUG "ath9k: Failed to set channel for new "
318                        "virtual wiphy\n");
319                 mutex_unlock(&sc->mutex);
320                 return;
321         }
322         mutex_unlock(&sc->mutex);
323
324         ath9k_wiphy_unpause_channel(sc);
325 }
326
327 /*
328  * ath9k version of ieee80211_tx_status() for TX frames that are generated
329  * internally in the driver.
330  */
331 void ath9k_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
332 {
333         struct ath_wiphy *aphy = hw->priv;
334         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
335         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
336         struct ath_tx_info_priv *tx_info_priv = ATH_TX_INFO_PRIV(tx_info);
337
338         if (tx_info_priv && tx_info_priv->frame_type == ATH9K_INT_PAUSE &&
339             aphy->state == ATH_WIPHY_PAUSING) {
340                 if (!(info->flags & IEEE80211_TX_STAT_ACK)) {
341                         printk(KERN_DEBUG "ath9k: %s: no ACK for pause "
342                                "frame\n", wiphy_name(hw->wiphy));
343                         /*
344                          * The AP did not reply; ignore this to allow us to
345                          * continue.
346                          */
347                 }
348                 aphy->state = ATH_WIPHY_PAUSED;
349                 if (!ath9k_wiphy_pausing(aphy->sc)) {
350                         /*
351                          * Drop from tasklet to work to allow mutex for channel
352                          * change.
353                          */
354                         queue_work(aphy->sc->hw->workqueue,
355                                    &aphy->sc->chan_work);
356                 }
357         }
358
359         kfree(tx_info_priv);
360         tx_info->rate_driver_data[0] = NULL;
361
362         dev_kfree_skb(skb);
363 }
364
365 static void ath9k_mark_paused(struct ath_wiphy *aphy)
366 {
367         struct ath_softc *sc = aphy->sc;
368         aphy->state = ATH_WIPHY_PAUSED;
369         if (!__ath9k_wiphy_pausing(sc))
370                 queue_work(sc->hw->workqueue, &sc->chan_work);
371 }
372
373 static void ath9k_pause_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
374 {
375         struct ath_wiphy *aphy = data;
376         struct ath_vif *avp = (void *) vif->drv_priv;
377
378         switch (vif->type) {
379         case NL80211_IFTYPE_STATION:
380                 if (!vif->bss_conf.assoc) {
381                         ath9k_mark_paused(aphy);
382                         break;
383                 }
384                 /* TODO: could avoid this if already in PS mode */
385                 if (ath9k_send_nullfunc(aphy, vif, avp->bssid, 1)) {
386                         printk(KERN_DEBUG "%s: failed to send PS nullfunc\n",
387                                __func__);
388                         ath9k_mark_paused(aphy);
389                 }
390                 break;
391         case NL80211_IFTYPE_AP:
392                 /* Beacon transmission is paused by aphy->state change */
393                 ath9k_mark_paused(aphy);
394                 break;
395         default:
396                 break;
397         }
398 }
399
400 /* caller must hold wiphy_lock */
401 static int __ath9k_wiphy_pause(struct ath_wiphy *aphy)
402 {
403         ieee80211_stop_queues(aphy->hw);
404         aphy->state = ATH_WIPHY_PAUSING;
405         /*
406          * TODO: handle PAUSING->PAUSED for the case where there are multiple
407          * active vifs (now we do it on the first vif getting ready; should be
408          * on the last)
409          */
410         ieee80211_iterate_active_interfaces_atomic(aphy->hw, ath9k_pause_iter,
411                                                    aphy);
412         return 0;
413 }
414
415 int ath9k_wiphy_pause(struct ath_wiphy *aphy)
416 {
417         int ret;
418         spin_lock_bh(&aphy->sc->wiphy_lock);
419         ret = __ath9k_wiphy_pause(aphy);
420         spin_unlock_bh(&aphy->sc->wiphy_lock);
421         return ret;
422 }
423
424 static void ath9k_unpause_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
425 {
426         struct ath_wiphy *aphy = data;
427         struct ath_vif *avp = (void *) vif->drv_priv;
428
429         switch (vif->type) {
430         case NL80211_IFTYPE_STATION:
431                 if (!vif->bss_conf.assoc)
432                         break;
433                 ath9k_send_nullfunc(aphy, vif, avp->bssid, 0);
434                 break;
435         case NL80211_IFTYPE_AP:
436                 /* Beacon transmission is re-enabled by aphy->state change */
437                 break;
438         default:
439                 break;
440         }
441 }
442
443 /* caller must hold wiphy_lock */
444 static int __ath9k_wiphy_unpause(struct ath_wiphy *aphy)
445 {
446         ieee80211_iterate_active_interfaces_atomic(aphy->hw,
447                                                    ath9k_unpause_iter, aphy);
448         aphy->state = ATH_WIPHY_ACTIVE;
449         ieee80211_wake_queues(aphy->hw);
450         return 0;
451 }
452
453 int ath9k_wiphy_unpause(struct ath_wiphy *aphy)
454 {
455         int ret;
456         spin_lock_bh(&aphy->sc->wiphy_lock);
457         ret = __ath9k_wiphy_unpause(aphy);
458         spin_unlock_bh(&aphy->sc->wiphy_lock);
459         return ret;
460 }
461
462 static void __ath9k_wiphy_mark_all_paused(struct ath_softc *sc)
463 {
464         int i;
465         if (sc->pri_wiphy->state != ATH_WIPHY_INACTIVE)
466                 sc->pri_wiphy->state = ATH_WIPHY_PAUSED;
467         for (i = 0; i < sc->num_sec_wiphy; i++) {
468                 if (sc->sec_wiphy[i] &&
469                     sc->sec_wiphy[i]->state != ATH_WIPHY_INACTIVE)
470                         sc->sec_wiphy[i]->state = ATH_WIPHY_PAUSED;
471         }
472 }
473
474 /* caller must hold wiphy_lock */
475 static void __ath9k_wiphy_pause_all(struct ath_softc *sc)
476 {
477         int i;
478         if (sc->pri_wiphy->state == ATH_WIPHY_ACTIVE)
479                 __ath9k_wiphy_pause(sc->pri_wiphy);
480         for (i = 0; i < sc->num_sec_wiphy; i++) {
481                 if (sc->sec_wiphy[i] &&
482                     sc->sec_wiphy[i]->state == ATH_WIPHY_ACTIVE)
483                         __ath9k_wiphy_pause(sc->sec_wiphy[i]);
484         }
485 }
486
487 int ath9k_wiphy_select(struct ath_wiphy *aphy)
488 {
489         struct ath_softc *sc = aphy->sc;
490         bool now;
491
492         spin_lock_bh(&sc->wiphy_lock);
493         if (__ath9k_wiphy_scanning(sc)) {
494                 /*
495                  * For now, we are using mac80211 sw scan and it expects to
496                  * have full control over channel changes, so avoid wiphy
497                  * scheduling during a scan. This could be optimized if the
498                  * scanning control were moved into the driver.
499                  */
500                 spin_unlock_bh(&sc->wiphy_lock);
501                 return -EBUSY;
502         }
503         if (__ath9k_wiphy_pausing(sc)) {
504                 if (sc->wiphy_select_failures == 0)
505                         sc->wiphy_select_first_fail = jiffies;
506                 sc->wiphy_select_failures++;
507                 if (time_after(jiffies, sc->wiphy_select_first_fail + HZ / 2))
508                 {
509                         printk(KERN_DEBUG "ath9k: Previous wiphy select timed "
510                                "out; disable/enable hw to recover\n");
511                         __ath9k_wiphy_mark_all_paused(sc);
512                         /*
513                          * TODO: this workaround to fix hardware is unlikely to
514                          * be specific to virtual wiphy changes. It can happen
515                          * on normal channel change, too, and as such, this
516                          * should really be made more generic. For example,
517                          * tricker radio disable/enable on GTT interrupt burst
518                          * (say, 10 GTT interrupts received without any TX
519                          * frame being completed)
520                          */
521                         spin_unlock_bh(&sc->wiphy_lock);
522                         ath_radio_disable(sc);
523                         ath_radio_enable(sc);
524                         queue_work(aphy->sc->hw->workqueue,
525                                    &aphy->sc->chan_work);
526                         return -EBUSY; /* previous select still in progress */
527                 }
528                 spin_unlock_bh(&sc->wiphy_lock);
529                 return -EBUSY; /* previous select still in progress */
530         }
531         sc->wiphy_select_failures = 0;
532
533         /* Store the new channel */
534         sc->chan_idx = aphy->chan_idx;
535         sc->chan_is_ht = aphy->chan_is_ht;
536         sc->next_wiphy = aphy;
537
538         __ath9k_wiphy_pause_all(sc);
539         now = !__ath9k_wiphy_pausing(aphy->sc);
540         spin_unlock_bh(&sc->wiphy_lock);
541
542         if (now) {
543                 /* Ready to request channel change immediately */
544                 queue_work(aphy->sc->hw->workqueue, &aphy->sc->chan_work);
545         }
546
547         /*
548          * wiphys will be unpaused in ath9k_tx_status() once channel has been
549          * changed if any wiphy needs time to become paused.
550          */
551
552         return 0;
553 }
554
555 bool ath9k_wiphy_started(struct ath_softc *sc)
556 {
557         int i;
558         spin_lock_bh(&sc->wiphy_lock);
559         if (sc->pri_wiphy->state != ATH_WIPHY_INACTIVE) {
560                 spin_unlock_bh(&sc->wiphy_lock);
561                 return true;
562         }
563         for (i = 0; i < sc->num_sec_wiphy; i++) {
564                 if (sc->sec_wiphy[i] &&
565                     sc->sec_wiphy[i]->state != ATH_WIPHY_INACTIVE) {
566                         spin_unlock_bh(&sc->wiphy_lock);
567                         return true;
568                 }
569         }
570         spin_unlock_bh(&sc->wiphy_lock);
571         return false;
572 }
573
574 static void ath9k_wiphy_pause_chan(struct ath_wiphy *aphy,
575                                    struct ath_wiphy *selected)
576 {
577         if (selected->state == ATH_WIPHY_SCAN) {
578                 if (aphy == selected)
579                         return;
580                 /*
581                  * Pause all other wiphys for the duration of the scan even if
582                  * they are on the current channel now.
583                  */
584         } else if (aphy->chan_idx == selected->chan_idx)
585                 return;
586         aphy->state = ATH_WIPHY_PAUSED;
587         ieee80211_stop_queues(aphy->hw);
588 }
589
590 void ath9k_wiphy_pause_all_forced(struct ath_softc *sc,
591                                   struct ath_wiphy *selected)
592 {
593         int i;
594         spin_lock_bh(&sc->wiphy_lock);
595         if (sc->pri_wiphy->state == ATH_WIPHY_ACTIVE)
596                 ath9k_wiphy_pause_chan(sc->pri_wiphy, selected);
597         for (i = 0; i < sc->num_sec_wiphy; i++) {
598                 if (sc->sec_wiphy[i] &&
599                     sc->sec_wiphy[i]->state == ATH_WIPHY_ACTIVE)
600                         ath9k_wiphy_pause_chan(sc->sec_wiphy[i], selected);
601         }
602         spin_unlock_bh(&sc->wiphy_lock);
603 }
604
605 void ath9k_wiphy_work(struct work_struct *work)
606 {
607         struct ath_softc *sc = container_of(work, struct ath_softc,
608                                             wiphy_work.work);
609         struct ath_wiphy *aphy = NULL;
610         bool first = true;
611
612         spin_lock_bh(&sc->wiphy_lock);
613
614         if (sc->wiphy_scheduler_int == 0) {
615                 /* wiphy scheduler is disabled */
616                 spin_unlock_bh(&sc->wiphy_lock);
617                 return;
618         }
619
620 try_again:
621         sc->wiphy_scheduler_index++;
622         while (sc->wiphy_scheduler_index <= sc->num_sec_wiphy) {
623                 aphy = sc->sec_wiphy[sc->wiphy_scheduler_index - 1];
624                 if (aphy && aphy->state != ATH_WIPHY_INACTIVE)
625                         break;
626
627                 sc->wiphy_scheduler_index++;
628                 aphy = NULL;
629         }
630         if (aphy == NULL) {
631                 sc->wiphy_scheduler_index = 0;
632                 if (sc->pri_wiphy->state == ATH_WIPHY_INACTIVE) {
633                         if (first) {
634                                 first = false;
635                                 goto try_again;
636                         }
637                         /* No wiphy is ready to be scheduled */
638                 } else
639                         aphy = sc->pri_wiphy;
640         }
641
642         spin_unlock_bh(&sc->wiphy_lock);
643
644         if (aphy &&
645             aphy->state != ATH_WIPHY_ACTIVE && aphy->state != ATH_WIPHY_SCAN &&
646             ath9k_wiphy_select(aphy)) {
647                 printk(KERN_DEBUG "ath9k: Failed to schedule virtual wiphy "
648                        "change\n");
649         }
650
651         queue_delayed_work(sc->hw->workqueue, &sc->wiphy_work,
652                            sc->wiphy_scheduler_int);
653 }
654
655 void ath9k_wiphy_set_scheduler(struct ath_softc *sc, unsigned int msec_int)
656 {
657         cancel_delayed_work_sync(&sc->wiphy_work);
658         sc->wiphy_scheduler_int = msecs_to_jiffies(msec_int);
659         if (sc->wiphy_scheduler_int)
660                 queue_delayed_work(sc->hw->workqueue, &sc->wiphy_work,
661                                    sc->wiphy_scheduler_int);
662 }