iwlwifi: drop lib80211 dependency
[linux-2.6.git] / drivers / net / wireless / iwlwifi / iwl-scan.c
1 /******************************************************************************
2  *
3  * GPL LICENSE SUMMARY
4  *
5  * Copyright(c) 2008 - 2009 Intel Corporation. All rights reserved.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of version 2 of the GNU General Public License as
9  * published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * General Public License for more details.
15  *
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17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
19  * USA
20  *
21  * The full GNU General Public License is included in this distribution
22  * in the file called LICENSE.GPL.
23  *
24  * Contact Information:
25  *  Intel Linux Wireless <ilw@linux.intel.com>
26  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
27  *****************************************************************************/
28 #include <linux/types.h>
29 #include <linux/etherdevice.h>
30 #include <net/mac80211.h>
31
32 #include "iwl-eeprom.h"
33 #include "iwl-dev.h"
34 #include "iwl-core.h"
35 #include "iwl-sta.h"
36 #include "iwl-io.h"
37 #include "iwl-helpers.h"
38
39 /* For active scan, listen ACTIVE_DWELL_TIME (msec) on each channel after
40  * sending probe req.  This should be set long enough to hear probe responses
41  * from more than one AP.  */
42 #define IWL_ACTIVE_DWELL_TIME_24    (30)       /* all times in msec */
43 #define IWL_ACTIVE_DWELL_TIME_52    (20)
44
45 #define IWL_ACTIVE_DWELL_FACTOR_24GHZ (3)
46 #define IWL_ACTIVE_DWELL_FACTOR_52GHZ (2)
47
48 /* For passive scan, listen PASSIVE_DWELL_TIME (msec) on each channel.
49  * Must be set longer than active dwell time.
50  * For the most reliable scan, set > AP beacon interval (typically 100msec). */
51 #define IWL_PASSIVE_DWELL_TIME_24   (20)       /* all times in msec */
52 #define IWL_PASSIVE_DWELL_TIME_52   (10)
53 #define IWL_PASSIVE_DWELL_BASE      (100)
54 #define IWL_CHANNEL_TUNE_TIME       5
55
56
57
58 /**
59  * iwl_scan_cancel - Cancel any currently executing HW scan
60  *
61  * NOTE: priv->mutex is not required before calling this function
62  */
63 int iwl_scan_cancel(struct iwl_priv *priv)
64 {
65         if (!test_bit(STATUS_SCAN_HW, &priv->status)) {
66                 clear_bit(STATUS_SCANNING, &priv->status);
67                 return 0;
68         }
69
70         if (test_bit(STATUS_SCANNING, &priv->status)) {
71                 if (!test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
72                         IWL_DEBUG_SCAN(priv, "Queuing scan abort.\n");
73                         set_bit(STATUS_SCAN_ABORTING, &priv->status);
74                         queue_work(priv->workqueue, &priv->abort_scan);
75
76                 } else
77                         IWL_DEBUG_SCAN(priv, "Scan abort already in progress.\n");
78
79                 return test_bit(STATUS_SCANNING, &priv->status);
80         }
81
82         return 0;
83 }
84 EXPORT_SYMBOL(iwl_scan_cancel);
85 /**
86  * iwl_scan_cancel_timeout - Cancel any currently executing HW scan
87  * @ms: amount of time to wait (in milliseconds) for scan to abort
88  *
89  * NOTE: priv->mutex must be held before calling this function
90  */
91 int iwl_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms)
92 {
93         unsigned long now = jiffies;
94         int ret;
95
96         ret = iwl_scan_cancel(priv);
97         if (ret && ms) {
98                 mutex_unlock(&priv->mutex);
99                 while (!time_after(jiffies, now + msecs_to_jiffies(ms)) &&
100                                 test_bit(STATUS_SCANNING, &priv->status))
101                         msleep(1);
102                 mutex_lock(&priv->mutex);
103
104                 return test_bit(STATUS_SCANNING, &priv->status);
105         }
106
107         return ret;
108 }
109 EXPORT_SYMBOL(iwl_scan_cancel_timeout);
110
111 static int iwl_send_scan_abort(struct iwl_priv *priv)
112 {
113         int ret = 0;
114         struct iwl_rx_packet *res;
115         struct iwl_host_cmd cmd = {
116                 .id = REPLY_SCAN_ABORT_CMD,
117                 .flags = CMD_WANT_SKB,
118         };
119
120         /* If there isn't a scan actively going on in the hardware
121          * then we are in between scan bands and not actually
122          * actively scanning, so don't send the abort command */
123         if (!test_bit(STATUS_SCAN_HW, &priv->status)) {
124                 clear_bit(STATUS_SCAN_ABORTING, &priv->status);
125                 return 0;
126         }
127
128         ret = iwl_send_cmd_sync(priv, &cmd);
129         if (ret) {
130                 clear_bit(STATUS_SCAN_ABORTING, &priv->status);
131                 return ret;
132         }
133
134         res = (struct iwl_rx_packet *)cmd.reply_skb->data;
135         if (res->u.status != CAN_ABORT_STATUS) {
136                 /* The scan abort will return 1 for success or
137                  * 2 for "failure".  A failure condition can be
138                  * due to simply not being in an active scan which
139                  * can occur if we send the scan abort before we
140                  * the microcode has notified us that a scan is
141                  * completed. */
142                 IWL_DEBUG_INFO(priv, "SCAN_ABORT returned %d.\n", res->u.status);
143                 clear_bit(STATUS_SCAN_ABORTING, &priv->status);
144                 clear_bit(STATUS_SCAN_HW, &priv->status);
145         }
146
147         priv->alloc_rxb_skb--;
148         dev_kfree_skb_any(cmd.reply_skb);
149
150         return ret;
151 }
152
153 /* Service response to REPLY_SCAN_CMD (0x80) */
154 static void iwl_rx_reply_scan(struct iwl_priv *priv,
155                               struct iwl_rx_mem_buffer *rxb)
156 {
157 #ifdef CONFIG_IWLWIFI_DEBUG
158         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
159         struct iwl_scanreq_notification *notif =
160             (struct iwl_scanreq_notification *)pkt->u.raw;
161
162         IWL_DEBUG_RX(priv, "Scan request status = 0x%x\n", notif->status);
163 #endif
164 }
165
166 /* Service SCAN_START_NOTIFICATION (0x82) */
167 static void iwl_rx_scan_start_notif(struct iwl_priv *priv,
168                                     struct iwl_rx_mem_buffer *rxb)
169 {
170         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
171         struct iwl_scanstart_notification *notif =
172             (struct iwl_scanstart_notification *)pkt->u.raw;
173         priv->scan_start_tsf = le32_to_cpu(notif->tsf_low);
174         IWL_DEBUG_SCAN(priv, "Scan start: "
175                        "%d [802.11%s] "
176                        "(TSF: 0x%08X:%08X) - %d (beacon timer %u)\n",
177                        notif->channel,
178                        notif->band ? "bg" : "a",
179                        le32_to_cpu(notif->tsf_high),
180                        le32_to_cpu(notif->tsf_low),
181                        notif->status, notif->beacon_timer);
182 }
183
184 /* Service SCAN_RESULTS_NOTIFICATION (0x83) */
185 static void iwl_rx_scan_results_notif(struct iwl_priv *priv,
186                                       struct iwl_rx_mem_buffer *rxb)
187 {
188 #ifdef CONFIG_IWLWIFI_DEBUG
189         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
190         struct iwl_scanresults_notification *notif =
191             (struct iwl_scanresults_notification *)pkt->u.raw;
192
193         IWL_DEBUG_SCAN(priv, "Scan ch.res: "
194                        "%d [802.11%s] "
195                        "(TSF: 0x%08X:%08X) - %d "
196                        "elapsed=%lu usec (%dms since last)\n",
197                        notif->channel,
198                        notif->band ? "bg" : "a",
199                        le32_to_cpu(notif->tsf_high),
200                        le32_to_cpu(notif->tsf_low),
201                        le32_to_cpu(notif->statistics[0]),
202                        le32_to_cpu(notif->tsf_low) - priv->scan_start_tsf,
203                        jiffies_to_msecs(elapsed_jiffies
204                                         (priv->last_scan_jiffies, jiffies)));
205 #endif
206
207         priv->last_scan_jiffies = jiffies;
208         priv->next_scan_jiffies = 0;
209 }
210
211 /* Service SCAN_COMPLETE_NOTIFICATION (0x84) */
212 static void iwl_rx_scan_complete_notif(struct iwl_priv *priv,
213                                        struct iwl_rx_mem_buffer *rxb)
214 {
215 #ifdef CONFIG_IWLWIFI_DEBUG
216         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
217         struct iwl_scancomplete_notification *scan_notif = (void *)pkt->u.raw;
218
219         IWL_DEBUG_SCAN(priv, "Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n",
220                        scan_notif->scanned_channels,
221                        scan_notif->tsf_low,
222                        scan_notif->tsf_high, scan_notif->status);
223 #endif
224
225         /* The HW is no longer scanning */
226         clear_bit(STATUS_SCAN_HW, &priv->status);
227
228         IWL_DEBUG_INFO(priv, "Scan pass on %sGHz took %dms\n",
229                        (priv->scan_bands & BIT(IEEE80211_BAND_2GHZ)) ?
230                                                 "2.4" : "5.2",
231                        jiffies_to_msecs(elapsed_jiffies
232                                         (priv->scan_pass_start, jiffies)));
233
234         /* Remove this scanned band from the list of pending
235          * bands to scan, band G precedes A in order of scanning
236          * as seen in iwl_bg_request_scan */
237         if (priv->scan_bands & BIT(IEEE80211_BAND_2GHZ))
238                 priv->scan_bands &= ~BIT(IEEE80211_BAND_2GHZ);
239         else if (priv->scan_bands &  BIT(IEEE80211_BAND_5GHZ))
240                 priv->scan_bands &= ~BIT(IEEE80211_BAND_5GHZ);
241
242         /* If a request to abort was given, or the scan did not succeed
243          * then we reset the scan state machine and terminate,
244          * re-queuing another scan if one has been requested */
245         if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
246                 IWL_DEBUG_INFO(priv, "Aborted scan completed.\n");
247                 clear_bit(STATUS_SCAN_ABORTING, &priv->status);
248         } else {
249                 /* If there are more bands on this scan pass reschedule */
250                 if (priv->scan_bands)
251                         goto reschedule;
252         }
253
254         priv->last_scan_jiffies = jiffies;
255         priv->next_scan_jiffies = 0;
256         IWL_DEBUG_INFO(priv, "Setting scan to off\n");
257
258         clear_bit(STATUS_SCANNING, &priv->status);
259
260         IWL_DEBUG_INFO(priv, "Scan took %dms\n",
261                 jiffies_to_msecs(elapsed_jiffies(priv->scan_start, jiffies)));
262
263         queue_work(priv->workqueue, &priv->scan_completed);
264
265         return;
266
267 reschedule:
268         priv->scan_pass_start = jiffies;
269         queue_work(priv->workqueue, &priv->request_scan);
270 }
271
272 void iwl_setup_rx_scan_handlers(struct iwl_priv *priv)
273 {
274         /* scan handlers */
275         priv->rx_handlers[REPLY_SCAN_CMD] = iwl_rx_reply_scan;
276         priv->rx_handlers[SCAN_START_NOTIFICATION] = iwl_rx_scan_start_notif;
277         priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] =
278                                         iwl_rx_scan_results_notif;
279         priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] =
280                                         iwl_rx_scan_complete_notif;
281 }
282 EXPORT_SYMBOL(iwl_setup_rx_scan_handlers);
283
284 inline u16 iwl_get_active_dwell_time(struct iwl_priv *priv,
285                                      enum ieee80211_band band,
286                                      u8 n_probes)
287 {
288         if (band == IEEE80211_BAND_5GHZ)
289                 return IWL_ACTIVE_DWELL_TIME_52 +
290                         IWL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1);
291         else
292                 return IWL_ACTIVE_DWELL_TIME_24 +
293                         IWL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1);
294 }
295 EXPORT_SYMBOL(iwl_get_active_dwell_time);
296
297 u16 iwl_get_passive_dwell_time(struct iwl_priv *priv,
298                                enum ieee80211_band band)
299 {
300         u16 passive = (band == IEEE80211_BAND_2GHZ) ?
301             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_24 :
302             IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_52;
303
304         if (iwl_is_associated(priv)) {
305                 /* If we're associated, we clamp the maximum passive
306                  * dwell time to be 98% of the beacon interval (minus
307                  * 2 * channel tune time) */
308                 passive = priv->beacon_int;
309                 if ((passive > IWL_PASSIVE_DWELL_BASE) || !passive)
310                         passive = IWL_PASSIVE_DWELL_BASE;
311                 passive = (passive * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
312         }
313
314         return passive;
315 }
316 EXPORT_SYMBOL(iwl_get_passive_dwell_time);
317
318 static int iwl_get_channels_for_scan(struct iwl_priv *priv,
319                                      enum ieee80211_band band,
320                                      u8 is_active, u8 n_probes,
321                                      struct iwl_scan_channel *scan_ch)
322 {
323         struct ieee80211_channel *chan;
324         const struct ieee80211_supported_band *sband;
325         const struct iwl_channel_info *ch_info;
326         u16 passive_dwell = 0;
327         u16 active_dwell = 0;
328         int added, i;
329         u16 channel;
330
331         sband = iwl_get_hw_mode(priv, band);
332         if (!sband)
333                 return 0;
334
335         active_dwell = iwl_get_active_dwell_time(priv, band, n_probes);
336         passive_dwell = iwl_get_passive_dwell_time(priv, band);
337
338         if (passive_dwell <= active_dwell)
339                 passive_dwell = active_dwell + 1;
340
341         for (i = 0, added = 0; i < priv->scan_request->n_channels; i++) {
342                 chan = priv->scan_request->channels[i];
343
344                 if (chan->band != band)
345                         continue;
346
347                 channel = ieee80211_frequency_to_channel(chan->center_freq);
348                 scan_ch->channel = cpu_to_le16(channel);
349
350                 ch_info = iwl_get_channel_info(priv, band, channel);
351                 if (!is_channel_valid(ch_info)) {
352                         IWL_DEBUG_SCAN(priv, "Channel %d is INVALID for this band.\n",
353                                         channel);
354                         continue;
355                 }
356
357                 if (!is_active || is_channel_passive(ch_info) ||
358                     (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN))
359                         scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE;
360                 else
361                         scan_ch->type = SCAN_CHANNEL_TYPE_ACTIVE;
362
363                 if (n_probes)
364                         scan_ch->type |= IWL_SCAN_PROBE_MASK(n_probes);
365
366                 scan_ch->active_dwell = cpu_to_le16(active_dwell);
367                 scan_ch->passive_dwell = cpu_to_le16(passive_dwell);
368
369                 /* Set txpower levels to defaults */
370                 scan_ch->dsp_atten = 110;
371
372                 /* NOTE: if we were doing 6Mb OFDM for scans we'd use
373                  * power level:
374                  * scan_ch->tx_gain = ((1 << 5) | (2 << 3)) | 3;
375                  */
376                 if (band == IEEE80211_BAND_5GHZ)
377                         scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3;
378                 else
379                         scan_ch->tx_gain = ((1 << 5) | (5 << 3));
380
381                 IWL_DEBUG_SCAN(priv, "Scanning ch=%d prob=0x%X [%s %d]\n",
382                                channel, le32_to_cpu(scan_ch->type),
383                                (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
384                                 "ACTIVE" : "PASSIVE",
385                                (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ?
386                                active_dwell : passive_dwell);
387
388                 scan_ch++;
389                 added++;
390         }
391
392         IWL_DEBUG_SCAN(priv, "total channels to scan %d \n", added);
393         return added;
394 }
395
396 void iwl_init_scan_params(struct iwl_priv *priv)
397 {
398         u8 ant_idx = fls(priv->hw_params.valid_tx_ant) - 1;
399         if (!priv->scan_tx_ant[IEEE80211_BAND_5GHZ])
400                 priv->scan_tx_ant[IEEE80211_BAND_5GHZ] = ant_idx;
401         if (!priv->scan_tx_ant[IEEE80211_BAND_2GHZ])
402                 priv->scan_tx_ant[IEEE80211_BAND_2GHZ] = ant_idx;
403 }
404
405 static int iwl_scan_initiate(struct iwl_priv *priv)
406 {
407         if (!iwl_is_ready_rf(priv)) {
408                 IWL_DEBUG_SCAN(priv, "Aborting scan due to not ready.\n");
409                 return -EIO;
410         }
411
412         if (test_bit(STATUS_SCANNING, &priv->status)) {
413                 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
414                 return -EAGAIN;
415         }
416
417         if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
418                 IWL_DEBUG_SCAN(priv, "Scan request while abort pending\n");
419                 return -EAGAIN;
420         }
421
422         IWL_DEBUG_INFO(priv, "Starting scan...\n");
423         set_bit(STATUS_SCANNING, &priv->status);
424         priv->scan_start = jiffies;
425         priv->scan_pass_start = priv->scan_start;
426
427         queue_work(priv->workqueue, &priv->request_scan);
428
429         return 0;
430 }
431
432 #define IWL_DELAY_NEXT_SCAN (HZ*2)
433
434 int iwl_mac_hw_scan(struct ieee80211_hw *hw,
435                      struct cfg80211_scan_request *req)
436 {
437         unsigned long flags;
438         struct iwl_priv *priv = hw->priv;
439         int ret, i;
440
441         IWL_DEBUG_MAC80211(priv, "enter\n");
442
443         mutex_lock(&priv->mutex);
444         spin_lock_irqsave(&priv->lock, flags);
445
446         if (!iwl_is_ready_rf(priv)) {
447                 ret = -EIO;
448                 IWL_DEBUG_MAC80211(priv, "leave - not ready or exit pending\n");
449                 goto out_unlock;
450         }
451
452         /* We don't schedule scan within next_scan_jiffies period.
453          * Avoid scanning during possible EAPOL exchange, return
454          * success immediately.
455          */
456         if (priv->next_scan_jiffies &&
457             time_after(priv->next_scan_jiffies, jiffies)) {
458                 IWL_DEBUG_SCAN(priv, "scan rejected: within next scan period\n");
459                 queue_work(priv->workqueue, &priv->scan_completed);
460                 ret = 0;
461                 goto out_unlock;
462         }
463
464         /* if we just finished scan ask for delay */
465         if (iwl_is_associated(priv) && priv->last_scan_jiffies &&
466             time_after(priv->last_scan_jiffies + IWL_DELAY_NEXT_SCAN, jiffies)) {
467                 IWL_DEBUG_SCAN(priv, "scan rejected: within previous scan period\n");
468                 queue_work(priv->workqueue, &priv->scan_completed);
469                 ret = 0;
470                 goto out_unlock;
471         }
472
473         priv->scan_bands = 0;
474         for (i = 0; i < req->n_channels; i++)
475                 priv->scan_bands |= BIT(req->channels[i]->band);
476
477         priv->scan_request = req;
478
479         ret = iwl_scan_initiate(priv);
480
481         IWL_DEBUG_MAC80211(priv, "leave\n");
482
483 out_unlock:
484         spin_unlock_irqrestore(&priv->lock, flags);
485         mutex_unlock(&priv->mutex);
486
487         return ret;
488 }
489 EXPORT_SYMBOL(iwl_mac_hw_scan);
490
491 #define IWL_SCAN_CHECK_WATCHDOG (7 * HZ)
492
493 void iwl_bg_scan_check(struct work_struct *data)
494 {
495         struct iwl_priv *priv =
496             container_of(data, struct iwl_priv, scan_check.work);
497
498         if (test_bit(STATUS_EXIT_PENDING, &priv->status))
499                 return;
500
501         mutex_lock(&priv->mutex);
502         if (test_bit(STATUS_SCANNING, &priv->status) ||
503             test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
504                 IWL_DEBUG_SCAN(priv, "Scan completion watchdog resetting "
505                         "adapter (%dms)\n",
506                         jiffies_to_msecs(IWL_SCAN_CHECK_WATCHDOG));
507
508                 if (!test_bit(STATUS_EXIT_PENDING, &priv->status))
509                         iwl_send_scan_abort(priv);
510         }
511         mutex_unlock(&priv->mutex);
512 }
513 EXPORT_SYMBOL(iwl_bg_scan_check);
514
515 /**
516  * iwl_fill_probe_req - fill in all required fields and IE for probe request
517  */
518
519 u16 iwl_fill_probe_req(struct iwl_priv *priv, struct ieee80211_mgmt *frame,
520                        const u8 *ies, int ie_len, int left)
521 {
522         int len = 0;
523         u8 *pos = NULL;
524
525         /* Make sure there is enough space for the probe request,
526          * two mandatory IEs and the data */
527         left -= 24;
528         if (left < 0)
529                 return 0;
530
531         frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
532         memcpy(frame->da, iwl_bcast_addr, ETH_ALEN);
533         memcpy(frame->sa, priv->mac_addr, ETH_ALEN);
534         memcpy(frame->bssid, iwl_bcast_addr, ETH_ALEN);
535         frame->seq_ctrl = 0;
536
537         len += 24;
538
539         /* ...next IE... */
540         pos = &frame->u.probe_req.variable[0];
541
542         /* fill in our indirect SSID IE */
543         left -= 2;
544         if (left < 0)
545                 return 0;
546         *pos++ = WLAN_EID_SSID;
547         *pos++ = 0;
548
549         len += 2;
550
551         if (WARN_ON(left < ie_len))
552                 return len;
553
554         memcpy(pos, ies, ie_len);
555         len += ie_len;
556         left -= ie_len;
557
558         return (u16)len;
559 }
560 EXPORT_SYMBOL(iwl_fill_probe_req);
561
562 static void iwl_bg_request_scan(struct work_struct *data)
563 {
564         struct iwl_priv *priv =
565             container_of(data, struct iwl_priv, request_scan);
566         struct iwl_host_cmd cmd = {
567                 .id = REPLY_SCAN_CMD,
568                 .len = sizeof(struct iwl_scan_cmd),
569                 .flags = CMD_SIZE_HUGE,
570         };
571         struct iwl_scan_cmd *scan;
572         struct ieee80211_conf *conf = NULL;
573         int ret = 0;
574         u32 rate_flags = 0;
575         u16 cmd_len;
576         u16 rx_chain = 0;
577         enum ieee80211_band band;
578         u8 n_probes = 0;
579         u8 rx_ant = priv->hw_params.valid_rx_ant;
580         u8 rate;
581         bool is_active = false;
582         int  chan_mod;
583
584         conf = ieee80211_get_hw_conf(priv->hw);
585
586         mutex_lock(&priv->mutex);
587
588         cancel_delayed_work(&priv->scan_check);
589
590         if (!iwl_is_ready(priv)) {
591                 IWL_WARN(priv, "request scan called when driver not ready.\n");
592                 goto done;
593         }
594
595         /* Make sure the scan wasn't canceled before this queued work
596          * was given the chance to run... */
597         if (!test_bit(STATUS_SCANNING, &priv->status))
598                 goto done;
599
600         /* This should never be called or scheduled if there is currently
601          * a scan active in the hardware. */
602         if (test_bit(STATUS_SCAN_HW, &priv->status)) {
603                 IWL_DEBUG_INFO(priv, "Multiple concurrent scan requests in parallel. "
604                                "Ignoring second request.\n");
605                 ret = -EIO;
606                 goto done;
607         }
608
609         if (test_bit(STATUS_EXIT_PENDING, &priv->status)) {
610                 IWL_DEBUG_SCAN(priv, "Aborting scan due to device shutdown\n");
611                 goto done;
612         }
613
614         if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
615                 IWL_DEBUG_HC(priv, "Scan request while abort pending.  Queuing.\n");
616                 goto done;
617         }
618
619         if (iwl_is_rfkill(priv)) {
620                 IWL_DEBUG_HC(priv, "Aborting scan due to RF Kill activation\n");
621                 goto done;
622         }
623
624         if (!test_bit(STATUS_READY, &priv->status)) {
625                 IWL_DEBUG_HC(priv, "Scan request while uninitialized.  Queuing.\n");
626                 goto done;
627         }
628
629         if (!priv->scan_bands) {
630                 IWL_DEBUG_HC(priv, "Aborting scan due to no requested bands\n");
631                 goto done;
632         }
633
634         if (!priv->scan) {
635                 priv->scan = kmalloc(sizeof(struct iwl_scan_cmd) +
636                                      IWL_MAX_SCAN_SIZE, GFP_KERNEL);
637                 if (!priv->scan) {
638                         ret = -ENOMEM;
639                         goto done;
640                 }
641         }
642         scan = priv->scan;
643         memset(scan, 0, sizeof(struct iwl_scan_cmd) + IWL_MAX_SCAN_SIZE);
644
645         scan->quiet_plcp_th = IWL_PLCP_QUIET_THRESH;
646         scan->quiet_time = IWL_ACTIVE_QUIET_TIME;
647
648         if (iwl_is_associated(priv)) {
649                 u16 interval = 0;
650                 u32 extra;
651                 u32 suspend_time = 100;
652                 u32 scan_suspend_time = 100;
653                 unsigned long flags;
654
655                 IWL_DEBUG_INFO(priv, "Scanning while associated...\n");
656
657                 spin_lock_irqsave(&priv->lock, flags);
658                 interval = priv->beacon_int;
659                 spin_unlock_irqrestore(&priv->lock, flags);
660
661                 scan->suspend_time = 0;
662                 scan->max_out_time = cpu_to_le32(200 * 1024);
663                 if (!interval)
664                         interval = suspend_time;
665
666                 extra = (suspend_time / interval) << 22;
667                 scan_suspend_time = (extra |
668                     ((suspend_time % interval) * 1024));
669                 scan->suspend_time = cpu_to_le32(scan_suspend_time);
670                 IWL_DEBUG_SCAN(priv, "suspend_time 0x%X beacon interval %d\n",
671                                scan_suspend_time, interval);
672         }
673
674         if (priv->scan_request->n_ssids) {
675                 int i, p = 0;
676                 IWL_DEBUG_SCAN(priv, "Kicking off active scan\n");
677                 for (i = 0; i < priv->scan_request->n_ssids; i++) {
678                         /* always does wildcard anyway */
679                         if (!priv->scan_request->ssids[i].ssid_len)
680                                 continue;
681                         scan->direct_scan[p].id = WLAN_EID_SSID;
682                         scan->direct_scan[p].len =
683                                 priv->scan_request->ssids[i].ssid_len;
684                         memcpy(scan->direct_scan[p].ssid,
685                                priv->scan_request->ssids[i].ssid,
686                                priv->scan_request->ssids[i].ssid_len);
687                         n_probes++;
688                         p++;
689                 }
690                 is_active = true;
691         } else
692                 IWL_DEBUG_SCAN(priv, "Start passive scan.\n");
693
694         scan->tx_cmd.tx_flags = TX_CMD_FLG_SEQ_CTL_MSK;
695         scan->tx_cmd.sta_id = priv->hw_params.bcast_sta_id;
696         scan->tx_cmd.stop_time.life_time = TX_CMD_LIFE_TIME_INFINITE;
697
698
699         if (priv->scan_bands & BIT(IEEE80211_BAND_2GHZ)) {
700                 band = IEEE80211_BAND_2GHZ;
701                 scan->flags = RXON_FLG_BAND_24G_MSK | RXON_FLG_AUTO_DETECT_MSK;
702                 chan_mod = le32_to_cpu(priv->active_rxon.flags & RXON_FLG_CHANNEL_MODE_MSK)
703                                        >> RXON_FLG_CHANNEL_MODE_POS;
704                 if (chan_mod == CHANNEL_MODE_PURE_40) {
705                         rate = IWL_RATE_6M_PLCP;
706                 } else {
707                         rate = IWL_RATE_1M_PLCP;
708                         rate_flags = RATE_MCS_CCK_MSK;
709                 }
710                 scan->good_CRC_th = 0;
711         } else if (priv->scan_bands & BIT(IEEE80211_BAND_5GHZ)) {
712                 band = IEEE80211_BAND_5GHZ;
713                 rate = IWL_RATE_6M_PLCP;
714                 /*
715                  * If active scaning is requested but a certain channel
716                  * is marked passive, we can do active scanning if we
717                  * detect transmissions.
718                  */
719                 scan->good_CRC_th = is_active ? IWL_GOOD_CRC_TH : 0;
720
721                 /* Force use of chains B and C (0x6) for scan Rx for 4965
722                  * Avoid A (0x1) because of its off-channel reception on A-band.
723                  */
724                 if ((priv->hw_rev & CSR_HW_REV_TYPE_MSK) == CSR_HW_REV_TYPE_4965)
725                         rx_ant = ANT_BC;
726         } else {
727                 IWL_WARN(priv, "Invalid scan band count\n");
728                 goto done;
729         }
730
731         priv->scan_tx_ant[band] =
732                          iwl_toggle_tx_ant(priv, priv->scan_tx_ant[band]);
733         rate_flags |= iwl_ant_idx_to_flags(priv->scan_tx_ant[band]);
734         scan->tx_cmd.rate_n_flags = iwl_hw_set_rate_n_flags(rate, rate_flags);
735
736         /* MIMO is not used here, but value is required */
737         rx_chain |= ANT_ABC << RXON_RX_CHAIN_VALID_POS;
738         rx_chain |= ANT_ABC << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS;
739         rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_SEL_POS;
740         rx_chain |= 0x1 << RXON_RX_CHAIN_DRIVER_FORCE_POS;
741         scan->rx_chain = cpu_to_le16(rx_chain);
742         cmd_len = iwl_fill_probe_req(priv,
743                                 (struct ieee80211_mgmt *)scan->data,
744                                 priv->scan_request->ie,
745                                 priv->scan_request->ie_len,
746                                 IWL_MAX_SCAN_SIZE - sizeof(*scan));
747
748         scan->tx_cmd.len = cpu_to_le16(cmd_len);
749
750         if (iwl_is_monitor_mode(priv))
751                 scan->filter_flags = RXON_FILTER_PROMISC_MSK;
752
753         scan->filter_flags |= (RXON_FILTER_ACCEPT_GRP_MSK |
754                                RXON_FILTER_BCON_AWARE_MSK);
755
756         scan->channel_count =
757                 iwl_get_channels_for_scan(priv, band, is_active, n_probes,
758                         (void *)&scan->data[le16_to_cpu(scan->tx_cmd.len)]);
759
760         if (scan->channel_count == 0) {
761                 IWL_DEBUG_SCAN(priv, "channel count %d\n", scan->channel_count);
762                 goto done;
763         }
764
765         cmd.len += le16_to_cpu(scan->tx_cmd.len) +
766             scan->channel_count * sizeof(struct iwl_scan_channel);
767         cmd.data = scan;
768         scan->len = cpu_to_le16(cmd.len);
769
770         set_bit(STATUS_SCAN_HW, &priv->status);
771         ret = iwl_send_cmd_sync(priv, &cmd);
772         if (ret)
773                 goto done;
774
775         queue_delayed_work(priv->workqueue, &priv->scan_check,
776                            IWL_SCAN_CHECK_WATCHDOG);
777
778         mutex_unlock(&priv->mutex);
779         return;
780
781  done:
782         /* Cannot perform scan. Make sure we clear scanning
783         * bits from status so next scan request can be performed.
784         * If we don't clear scanning status bit here all next scan
785         * will fail
786         */
787         clear_bit(STATUS_SCAN_HW, &priv->status);
788         clear_bit(STATUS_SCANNING, &priv->status);
789         /* inform mac80211 scan aborted */
790         queue_work(priv->workqueue, &priv->scan_completed);
791         mutex_unlock(&priv->mutex);
792 }
793
794 void iwl_bg_abort_scan(struct work_struct *work)
795 {
796         struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan);
797
798         if (!test_bit(STATUS_READY, &priv->status) ||
799             !test_bit(STATUS_GEO_CONFIGURED, &priv->status))
800                 return;
801
802         mutex_lock(&priv->mutex);
803
804         set_bit(STATUS_SCAN_ABORTING, &priv->status);
805         iwl_send_scan_abort(priv);
806
807         mutex_unlock(&priv->mutex);
808 }
809 EXPORT_SYMBOL(iwl_bg_abort_scan);
810
811 void iwl_bg_scan_completed(struct work_struct *work)
812 {
813         struct iwl_priv *priv =
814             container_of(work, struct iwl_priv, scan_completed);
815
816         IWL_DEBUG_SCAN(priv, "SCAN complete scan\n");
817
818         cancel_delayed_work(&priv->scan_check);
819
820         ieee80211_scan_completed(priv->hw, false);
821
822         if (test_bit(STATUS_EXIT_PENDING, &priv->status))
823                 return;
824
825         /* Since setting the TXPOWER may have been deferred while
826          * performing the scan, fire one off */
827         mutex_lock(&priv->mutex);
828         iwl_set_tx_power(priv, priv->tx_power_user_lmt, true);
829         mutex_unlock(&priv->mutex);
830 }
831 EXPORT_SYMBOL(iwl_bg_scan_completed);
832
833 void iwl_setup_scan_deferred_work(struct iwl_priv *priv)
834 {
835         INIT_WORK(&priv->scan_completed, iwl_bg_scan_completed);
836         INIT_WORK(&priv->request_scan, iwl_bg_request_scan);
837         INIT_WORK(&priv->abort_scan, iwl_bg_abort_scan);
838         INIT_DELAYED_WORK(&priv->scan_check, iwl_bg_scan_check);
839 }
840 EXPORT_SYMBOL(iwl_setup_scan_deferred_work);
841