proc: use seq_puts()/seq_putc() where possible
[linux-2.6/next.git] / drivers / net / wireless / iwlwifi / iwl-scan.c
blob12d9363d0afe161774abd5c9b3fd3d95a9e31aa0
1 /******************************************************************************
3 * GPL LICENSE SUMMARY
5 * Copyright(c) 2008 - 2010 Intel Corporation. All rights reserved.
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.
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.
16 * You should have received a copy of the GNU General Public License
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
21 * The full GNU General Public License is included in this distribution
22 * in the file called LICENSE.GPL.
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/slab.h>
29 #include <linux/types.h>
30 #include <linux/etherdevice.h>
31 #include <net/mac80211.h>
33 #include "iwl-eeprom.h"
34 #include "iwl-dev.h"
35 #include "iwl-core.h"
36 #include "iwl-sta.h"
37 #include "iwl-io.h"
38 #include "iwl-helpers.h"
40 /* For active scan, listen ACTIVE_DWELL_TIME (msec) on each channel after
41 * sending probe req. This should be set long enough to hear probe responses
42 * from more than one AP. */
43 #define IWL_ACTIVE_DWELL_TIME_24 (30) /* all times in msec */
44 #define IWL_ACTIVE_DWELL_TIME_52 (20)
46 #define IWL_ACTIVE_DWELL_FACTOR_24GHZ (3)
47 #define IWL_ACTIVE_DWELL_FACTOR_52GHZ (2)
49 /* For passive scan, listen PASSIVE_DWELL_TIME (msec) on each channel.
50 * Must be set longer than active dwell time.
51 * For the most reliable scan, set > AP beacon interval (typically 100msec). */
52 #define IWL_PASSIVE_DWELL_TIME_24 (20) /* all times in msec */
53 #define IWL_PASSIVE_DWELL_TIME_52 (10)
54 #define IWL_PASSIVE_DWELL_BASE (100)
55 #define IWL_CHANNEL_TUNE_TIME 5
57 static int iwl_send_scan_abort(struct iwl_priv *priv)
59 int ret;
60 struct iwl_rx_packet *pkt;
61 struct iwl_host_cmd cmd = {
62 .id = REPLY_SCAN_ABORT_CMD,
63 .flags = CMD_WANT_SKB,
66 /* Exit instantly with error when device is not ready
67 * to receive scan abort command or it does not perform
68 * hardware scan currently */
69 if (!test_bit(STATUS_READY, &priv->status) ||
70 !test_bit(STATUS_GEO_CONFIGURED, &priv->status) ||
71 !test_bit(STATUS_SCAN_HW, &priv->status) ||
72 test_bit(STATUS_FW_ERROR, &priv->status) ||
73 test_bit(STATUS_EXIT_PENDING, &priv->status))
74 return -EIO;
76 ret = iwl_send_cmd_sync(priv, &cmd);
77 if (ret)
78 return ret;
80 pkt = (struct iwl_rx_packet *)cmd.reply_page;
81 if (pkt->u.status != CAN_ABORT_STATUS) {
82 /* The scan abort will return 1 for success or
83 * 2 for "failure". A failure condition can be
84 * due to simply not being in an active scan which
85 * can occur if we send the scan abort before we
86 * the microcode has notified us that a scan is
87 * completed. */
88 IWL_DEBUG_SCAN(priv, "SCAN_ABORT ret %d.\n", pkt->u.status);
89 ret = -EIO;
92 iwl_free_pages(priv, cmd.reply_page);
93 return ret;
96 static void iwl_complete_scan(struct iwl_priv *priv, bool aborted)
98 /* check if scan was requested from mac80211 */
99 if (priv->scan_request) {
100 IWL_DEBUG_SCAN(priv, "Complete scan in mac80211\n");
101 ieee80211_scan_completed(priv->hw, aborted);
104 priv->is_internal_short_scan = false;
105 priv->scan_vif = NULL;
106 priv->scan_request = NULL;
109 void iwl_force_scan_end(struct iwl_priv *priv)
111 lockdep_assert_held(&priv->mutex);
113 if (!test_bit(STATUS_SCANNING, &priv->status)) {
114 IWL_DEBUG_SCAN(priv, "Forcing scan end while not scanning\n");
115 return;
118 IWL_DEBUG_SCAN(priv, "Forcing scan end\n");
119 clear_bit(STATUS_SCANNING, &priv->status);
120 clear_bit(STATUS_SCAN_HW, &priv->status);
121 clear_bit(STATUS_SCAN_ABORTING, &priv->status);
122 iwl_complete_scan(priv, true);
125 static void iwl_do_scan_abort(struct iwl_priv *priv)
127 int ret;
129 lockdep_assert_held(&priv->mutex);
131 if (!test_bit(STATUS_SCANNING, &priv->status)) {
132 IWL_DEBUG_SCAN(priv, "Not performing scan to abort\n");
133 return;
136 if (test_and_set_bit(STATUS_SCAN_ABORTING, &priv->status)) {
137 IWL_DEBUG_SCAN(priv, "Scan abort in progress\n");
138 return;
141 ret = iwl_send_scan_abort(priv);
142 if (ret) {
143 IWL_DEBUG_SCAN(priv, "Send scan abort failed %d\n", ret);
144 iwl_force_scan_end(priv);
145 } else
146 IWL_DEBUG_SCAN(priv, "Sucessfully send scan abort\n");
150 * iwl_scan_cancel - Cancel any currently executing HW scan
152 int iwl_scan_cancel(struct iwl_priv *priv)
154 IWL_DEBUG_SCAN(priv, "Queuing abort scan\n");
155 queue_work(priv->workqueue, &priv->abort_scan);
156 return 0;
158 EXPORT_SYMBOL(iwl_scan_cancel);
161 * iwl_scan_cancel_timeout - Cancel any currently executing HW scan
162 * @ms: amount of time to wait (in milliseconds) for scan to abort
165 int iwl_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms)
167 unsigned long timeout = jiffies + msecs_to_jiffies(ms);
169 lockdep_assert_held(&priv->mutex);
171 IWL_DEBUG_SCAN(priv, "Scan cancel timeout\n");
173 iwl_do_scan_abort(priv);
175 while (time_before_eq(jiffies, timeout)) {
176 if (!test_bit(STATUS_SCAN_HW, &priv->status))
177 break;
178 msleep(20);
181 return test_bit(STATUS_SCAN_HW, &priv->status);
183 EXPORT_SYMBOL(iwl_scan_cancel_timeout);
185 /* Service response to REPLY_SCAN_CMD (0x80) */
186 static void iwl_rx_reply_scan(struct iwl_priv *priv,
187 struct iwl_rx_mem_buffer *rxb)
189 #ifdef CONFIG_IWLWIFI_DEBUG
190 struct iwl_rx_packet *pkt = rxb_addr(rxb);
191 struct iwl_scanreq_notification *notif =
192 (struct iwl_scanreq_notification *)pkt->u.raw;
194 IWL_DEBUG_SCAN(priv, "Scan request status = 0x%x\n", notif->status);
195 #endif
198 /* Service SCAN_START_NOTIFICATION (0x82) */
199 static void iwl_rx_scan_start_notif(struct iwl_priv *priv,
200 struct iwl_rx_mem_buffer *rxb)
202 struct iwl_rx_packet *pkt = rxb_addr(rxb);
203 struct iwl_scanstart_notification *notif =
204 (struct iwl_scanstart_notification *)pkt->u.raw;
205 priv->scan_start_tsf = le32_to_cpu(notif->tsf_low);
206 IWL_DEBUG_SCAN(priv, "Scan start: "
207 "%d [802.11%s] "
208 "(TSF: 0x%08X:%08X) - %d (beacon timer %u)\n",
209 notif->channel,
210 notif->band ? "bg" : "a",
211 le32_to_cpu(notif->tsf_high),
212 le32_to_cpu(notif->tsf_low),
213 notif->status, notif->beacon_timer);
216 /* Service SCAN_RESULTS_NOTIFICATION (0x83) */
217 static void iwl_rx_scan_results_notif(struct iwl_priv *priv,
218 struct iwl_rx_mem_buffer *rxb)
220 #ifdef CONFIG_IWLWIFI_DEBUG
221 struct iwl_rx_packet *pkt = rxb_addr(rxb);
222 struct iwl_scanresults_notification *notif =
223 (struct iwl_scanresults_notification *)pkt->u.raw;
225 IWL_DEBUG_SCAN(priv, "Scan ch.res: "
226 "%d [802.11%s] "
227 "(TSF: 0x%08X:%08X) - %d "
228 "elapsed=%lu usec\n",
229 notif->channel,
230 notif->band ? "bg" : "a",
231 le32_to_cpu(notif->tsf_high),
232 le32_to_cpu(notif->tsf_low),
233 le32_to_cpu(notif->statistics[0]),
234 le32_to_cpu(notif->tsf_low) - priv->scan_start_tsf);
235 #endif
238 /* Service SCAN_COMPLETE_NOTIFICATION (0x84) */
239 static void iwl_rx_scan_complete_notif(struct iwl_priv *priv,
240 struct iwl_rx_mem_buffer *rxb)
242 struct iwl_rx_packet *pkt = rxb_addr(rxb);
243 struct iwl_scancomplete_notification *scan_notif = (void *)pkt->u.raw;
245 IWL_DEBUG_SCAN(priv, "Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n",
246 scan_notif->scanned_channels,
247 scan_notif->tsf_low,
248 scan_notif->tsf_high, scan_notif->status);
250 /* The HW is no longer scanning */
251 clear_bit(STATUS_SCAN_HW, &priv->status);
253 IWL_DEBUG_SCAN(priv, "Scan on %sGHz took %dms\n",
254 (priv->scan_band == IEEE80211_BAND_2GHZ) ? "2.4" : "5.2",
255 jiffies_to_msecs(jiffies - priv->scan_start));
257 queue_work(priv->workqueue, &priv->scan_completed);
259 if (priv->iw_mode != NL80211_IFTYPE_ADHOC &&
260 priv->cfg->bt_params &&
261 priv->cfg->bt_params->advanced_bt_coexist &&
262 priv->bt_status != scan_notif->bt_status) {
263 if (scan_notif->bt_status) {
264 /* BT on */
265 if (!priv->bt_ch_announce)
266 priv->bt_traffic_load =
267 IWL_BT_COEX_TRAFFIC_LOAD_HIGH;
269 * otherwise, no traffic load information provided
270 * no changes made
272 } else {
273 /* BT off */
274 priv->bt_traffic_load =
275 IWL_BT_COEX_TRAFFIC_LOAD_NONE;
277 priv->bt_status = scan_notif->bt_status;
278 queue_work(priv->workqueue, &priv->bt_traffic_change_work);
282 void iwl_setup_rx_scan_handlers(struct iwl_priv *priv)
284 /* scan handlers */
285 priv->rx_handlers[REPLY_SCAN_CMD] = iwl_rx_reply_scan;
286 priv->rx_handlers[SCAN_START_NOTIFICATION] = iwl_rx_scan_start_notif;
287 priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] =
288 iwl_rx_scan_results_notif;
289 priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] =
290 iwl_rx_scan_complete_notif;
292 EXPORT_SYMBOL(iwl_setup_rx_scan_handlers);
294 inline u16 iwl_get_active_dwell_time(struct iwl_priv *priv,
295 enum ieee80211_band band,
296 u8 n_probes)
298 if (band == IEEE80211_BAND_5GHZ)
299 return IWL_ACTIVE_DWELL_TIME_52 +
300 IWL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1);
301 else
302 return IWL_ACTIVE_DWELL_TIME_24 +
303 IWL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1);
305 EXPORT_SYMBOL(iwl_get_active_dwell_time);
307 u16 iwl_get_passive_dwell_time(struct iwl_priv *priv,
308 enum ieee80211_band band,
309 struct ieee80211_vif *vif)
311 struct iwl_rxon_context *ctx;
312 u16 passive = (band == IEEE80211_BAND_2GHZ) ?
313 IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_24 :
314 IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_52;
316 if (iwl_is_any_associated(priv)) {
318 * If we're associated, we clamp the maximum passive
319 * dwell time to be 98% of the smallest beacon interval
320 * (minus 2 * channel tune time)
322 for_each_context(priv, ctx) {
323 u16 value;
325 if (!iwl_is_associated_ctx(ctx))
326 continue;
327 value = ctx->vif ? ctx->vif->bss_conf.beacon_int : 0;
328 if ((value > IWL_PASSIVE_DWELL_BASE) || !value)
329 value = IWL_PASSIVE_DWELL_BASE;
330 value = (value * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
331 passive = min(value, passive);
335 return passive;
337 EXPORT_SYMBOL(iwl_get_passive_dwell_time);
339 void iwl_init_scan_params(struct iwl_priv *priv)
341 u8 ant_idx = fls(priv->hw_params.valid_tx_ant) - 1;
342 if (!priv->scan_tx_ant[IEEE80211_BAND_5GHZ])
343 priv->scan_tx_ant[IEEE80211_BAND_5GHZ] = ant_idx;
344 if (!priv->scan_tx_ant[IEEE80211_BAND_2GHZ])
345 priv->scan_tx_ant[IEEE80211_BAND_2GHZ] = ant_idx;
347 EXPORT_SYMBOL(iwl_init_scan_params);
349 static int __must_check iwl_scan_initiate(struct iwl_priv *priv,
350 struct ieee80211_vif *vif,
351 bool internal,
352 enum ieee80211_band band)
354 int ret;
356 lockdep_assert_held(&priv->mutex);
358 if (WARN_ON(!priv->cfg->ops->utils->request_scan))
359 return -EOPNOTSUPP;
361 cancel_delayed_work(&priv->scan_check);
363 if (!iwl_is_ready_rf(priv)) {
364 IWL_WARN(priv, "Request scan called when driver not ready.\n");
365 return -EIO;
368 if (test_bit(STATUS_SCAN_HW, &priv->status)) {
369 IWL_DEBUG_SCAN(priv,
370 "Multiple concurrent scan requests in parallel.\n");
371 return -EBUSY;
374 if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
375 IWL_DEBUG_SCAN(priv, "Scan request while abort pending.\n");
376 return -EBUSY;
379 IWL_DEBUG_SCAN(priv, "Starting %sscan...\n",
380 internal ? "internal short " : "");
382 set_bit(STATUS_SCANNING, &priv->status);
383 priv->is_internal_short_scan = internal;
384 priv->scan_start = jiffies;
385 priv->scan_band = band;
387 ret = priv->cfg->ops->utils->request_scan(priv, vif);
388 if (ret) {
389 clear_bit(STATUS_SCANNING, &priv->status);
390 priv->is_internal_short_scan = false;
391 return ret;
394 queue_delayed_work(priv->workqueue, &priv->scan_check,
395 IWL_SCAN_CHECK_WATCHDOG);
397 return 0;
400 int iwl_mac_hw_scan(struct ieee80211_hw *hw,
401 struct ieee80211_vif *vif,
402 struct cfg80211_scan_request *req)
404 struct iwl_priv *priv = hw->priv;
405 int ret;
407 IWL_DEBUG_MAC80211(priv, "enter\n");
409 if (req->n_channels == 0)
410 return -EINVAL;
412 mutex_lock(&priv->mutex);
414 if (test_bit(STATUS_SCANNING, &priv->status) &&
415 !priv->is_internal_short_scan) {
416 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
417 ret = -EAGAIN;
418 goto out_unlock;
421 /* mac80211 will only ask for one band at a time */
422 priv->scan_request = req;
423 priv->scan_vif = vif;
426 * If an internal scan is in progress, just set
427 * up the scan_request as per above.
429 if (priv->is_internal_short_scan) {
430 IWL_DEBUG_SCAN(priv, "SCAN request during internal scan\n");
431 ret = 0;
432 } else
433 ret = iwl_scan_initiate(priv, vif, false,
434 req->channels[0]->band);
436 IWL_DEBUG_MAC80211(priv, "leave\n");
438 out_unlock:
439 mutex_unlock(&priv->mutex);
441 return ret;
443 EXPORT_SYMBOL(iwl_mac_hw_scan);
446 * internal short scan, this function should only been called while associated.
447 * It will reset and tune the radio to prevent possible RF related problem
449 void iwl_internal_short_hw_scan(struct iwl_priv *priv)
451 queue_work(priv->workqueue, &priv->start_internal_scan);
454 static void iwl_bg_start_internal_scan(struct work_struct *work)
456 struct iwl_priv *priv =
457 container_of(work, struct iwl_priv, start_internal_scan);
459 IWL_DEBUG_SCAN(priv, "Start internal scan\n");
461 mutex_lock(&priv->mutex);
463 if (priv->is_internal_short_scan == true) {
464 IWL_DEBUG_SCAN(priv, "Internal scan already in progress\n");
465 goto unlock;
468 if (test_bit(STATUS_SCANNING, &priv->status)) {
469 IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
470 goto unlock;
473 if (iwl_scan_initiate(priv, NULL, true, priv->band))
474 IWL_DEBUG_SCAN(priv, "failed to start internal short scan\n");
475 unlock:
476 mutex_unlock(&priv->mutex);
479 static void iwl_bg_scan_check(struct work_struct *data)
481 struct iwl_priv *priv =
482 container_of(data, struct iwl_priv, scan_check.work);
484 IWL_DEBUG_SCAN(priv, "Scan check work\n");
486 /* Since we are here firmware does not finish scan and
487 * most likely is in bad shape, so we don't bother to
488 * send abort command, just force scan complete to mac80211 */
489 mutex_lock(&priv->mutex);
490 iwl_force_scan_end(priv);
491 mutex_unlock(&priv->mutex);
495 * iwl_fill_probe_req - fill in all required fields and IE for probe request
498 u16 iwl_fill_probe_req(struct iwl_priv *priv, struct ieee80211_mgmt *frame,
499 const u8 *ta, const u8 *ies, int ie_len, int left)
501 int len = 0;
502 u8 *pos = NULL;
504 /* Make sure there is enough space for the probe request,
505 * two mandatory IEs and the data */
506 left -= 24;
507 if (left < 0)
508 return 0;
510 frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
511 memcpy(frame->da, iwl_bcast_addr, ETH_ALEN);
512 memcpy(frame->sa, ta, ETH_ALEN);
513 memcpy(frame->bssid, iwl_bcast_addr, ETH_ALEN);
514 frame->seq_ctrl = 0;
516 len += 24;
518 /* ...next IE... */
519 pos = &frame->u.probe_req.variable[0];
521 /* fill in our indirect SSID IE */
522 left -= 2;
523 if (left < 0)
524 return 0;
525 *pos++ = WLAN_EID_SSID;
526 *pos++ = 0;
528 len += 2;
530 if (WARN_ON(left < ie_len))
531 return len;
533 if (ies && ie_len) {
534 memcpy(pos, ies, ie_len);
535 len += ie_len;
538 return (u16)len;
540 EXPORT_SYMBOL(iwl_fill_probe_req);
542 static void iwl_bg_abort_scan(struct work_struct *work)
544 struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan);
546 IWL_DEBUG_SCAN(priv, "Abort scan work\n");
548 /* We keep scan_check work queued in case when firmware will not
549 * report back scan completed notification */
550 mutex_lock(&priv->mutex);
551 iwl_scan_cancel_timeout(priv, 200);
552 mutex_unlock(&priv->mutex);
555 static void iwl_bg_scan_completed(struct work_struct *work)
557 struct iwl_priv *priv =
558 container_of(work, struct iwl_priv, scan_completed);
559 bool aborted;
561 IWL_DEBUG_SCAN(priv, "Completed %sscan.\n",
562 priv->is_internal_short_scan ? "internal short " : "");
564 cancel_delayed_work(&priv->scan_check);
566 mutex_lock(&priv->mutex);
568 aborted = test_and_clear_bit(STATUS_SCAN_ABORTING, &priv->status);
569 if (aborted)
570 IWL_DEBUG_SCAN(priv, "Aborted scan completed.\n");
572 if (!test_and_clear_bit(STATUS_SCANNING, &priv->status)) {
573 IWL_DEBUG_SCAN(priv, "Scan already completed.\n");
574 goto out_settings;
577 if (priv->is_internal_short_scan && !aborted) {
578 int err;
580 /* Check if mac80211 requested scan during our internal scan */
581 if (priv->scan_request == NULL)
582 goto out_complete;
584 /* If so request a new scan */
585 err = iwl_scan_initiate(priv, priv->scan_vif, false,
586 priv->scan_request->channels[0]->band);
587 if (err) {
588 IWL_DEBUG_SCAN(priv,
589 "failed to initiate pending scan: %d\n", err);
590 aborted = true;
591 goto out_complete;
594 goto out;
597 out_complete:
598 iwl_complete_scan(priv, aborted);
600 out_settings:
601 /* Can we still talk to firmware ? */
602 if (!iwl_is_ready_rf(priv))
603 goto out;
606 * We do not commit power settings while scan is pending,
607 * do it now if the settings changed.
609 iwl_power_set_mode(priv, &priv->power_data.sleep_cmd_next, false);
610 iwl_set_tx_power(priv, priv->tx_power_next, false);
612 priv->cfg->ops->utils->post_scan(priv);
614 out:
615 mutex_unlock(&priv->mutex);
618 void iwl_setup_scan_deferred_work(struct iwl_priv *priv)
620 INIT_WORK(&priv->scan_completed, iwl_bg_scan_completed);
621 INIT_WORK(&priv->abort_scan, iwl_bg_abort_scan);
622 INIT_WORK(&priv->start_internal_scan, iwl_bg_start_internal_scan);
623 INIT_DELAYED_WORK(&priv->scan_check, iwl_bg_scan_check);
625 EXPORT_SYMBOL(iwl_setup_scan_deferred_work);
627 void iwl_cancel_scan_deferred_work(struct iwl_priv *priv)
629 cancel_work_sync(&priv->start_internal_scan);
630 cancel_work_sync(&priv->abort_scan);
631 cancel_work_sync(&priv->scan_completed);
633 if (cancel_delayed_work_sync(&priv->scan_check)) {
634 mutex_lock(&priv->mutex);
635 iwl_force_scan_end(priv);
636 mutex_unlock(&priv->mutex);
639 EXPORT_SYMBOL(iwl_cancel_scan_deferred_work);