diff options
Diffstat (limited to 'drivers/net/wireless/iwlegacy/iwl-scan.c')
| -rw-r--r-- | drivers/net/wireless/iwlegacy/iwl-scan.c | 625 |
1 files changed, 625 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlegacy/iwl-scan.c b/drivers/net/wireless/iwlegacy/iwl-scan.c new file mode 100644 index 00000000000..60f597f796c --- /dev/null +++ b/drivers/net/wireless/iwlegacy/iwl-scan.c @@ -0,0 +1,625 @@ +/****************************************************************************** + * + * GPL LICENSE SUMMARY + * + * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, + * USA + * + * The full GNU General Public License is included in this distribution + * in the file called LICENSE.GPL. + * + * Contact Information: + * Intel Linux Wireless <ilw@linux.intel.com> + * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497 + *****************************************************************************/ +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/etherdevice.h> +#include <net/mac80211.h> + +#include "iwl-eeprom.h" +#include "iwl-dev.h" +#include "iwl-core.h" +#include "iwl-sta.h" +#include "iwl-io.h" +#include "iwl-helpers.h" + +/* For active scan, listen ACTIVE_DWELL_TIME (msec) on each channel after + * sending probe req. This should be set long enough to hear probe responses + * from more than one AP. */ +#define IWL_ACTIVE_DWELL_TIME_24 (30) /* all times in msec */ +#define IWL_ACTIVE_DWELL_TIME_52 (20) + +#define IWL_ACTIVE_DWELL_FACTOR_24GHZ (3) +#define IWL_ACTIVE_DWELL_FACTOR_52GHZ (2) + +/* For passive scan, listen PASSIVE_DWELL_TIME (msec) on each channel. + * Must be set longer than active dwell time. + * For the most reliable scan, set > AP beacon interval (typically 100msec). */ +#define IWL_PASSIVE_DWELL_TIME_24 (20) /* all times in msec */ +#define IWL_PASSIVE_DWELL_TIME_52 (10) +#define IWL_PASSIVE_DWELL_BASE (100) +#define IWL_CHANNEL_TUNE_TIME 5 + +static int iwl_legacy_send_scan_abort(struct iwl_priv *priv) +{ + int ret; + struct iwl_rx_packet *pkt; + struct iwl_host_cmd cmd = { + .id = REPLY_SCAN_ABORT_CMD, + .flags = CMD_WANT_SKB, + }; + + /* Exit instantly with error when device is not ready + * to receive scan abort command or it does not perform + * hardware scan currently */ + if (!test_bit(STATUS_READY, &priv->status) || + !test_bit(STATUS_GEO_CONFIGURED, &priv->status) || + !test_bit(STATUS_SCAN_HW, &priv->status) || + test_bit(STATUS_FW_ERROR, &priv->status) || + test_bit(STATUS_EXIT_PENDING, &priv->status)) + return -EIO; + + ret = iwl_legacy_send_cmd_sync(priv, &cmd); + if (ret) + return ret; + + pkt = (struct iwl_rx_packet *)cmd.reply_page; + if (pkt->u.status != CAN_ABORT_STATUS) { + /* The scan abort will return 1 for success or + * 2 for "failure". A failure condition can be + * due to simply not being in an active scan which + * can occur if we send the scan abort before we + * the microcode has notified us that a scan is + * completed. */ + IWL_DEBUG_SCAN(priv, "SCAN_ABORT ret %d.\n", pkt->u.status); + ret = -EIO; + } + + iwl_legacy_free_pages(priv, cmd.reply_page); + return ret; +} + +static void iwl_legacy_complete_scan(struct iwl_priv *priv, bool aborted) +{ + /* check if scan was requested from mac80211 */ + if (priv->scan_request) { + IWL_DEBUG_SCAN(priv, "Complete scan in mac80211\n"); + ieee80211_scan_completed(priv->hw, aborted); + } + + priv->is_internal_short_scan = false; + priv->scan_vif = NULL; + priv->scan_request = NULL; +} + +void iwl_legacy_force_scan_end(struct iwl_priv *priv) +{ + lockdep_assert_held(&priv->mutex); + + if (!test_bit(STATUS_SCANNING, &priv->status)) { + IWL_DEBUG_SCAN(priv, "Forcing scan end while not scanning\n"); + return; + } + + IWL_DEBUG_SCAN(priv, "Forcing scan end\n"); + clear_bit(STATUS_SCANNING, &priv->status); + clear_bit(STATUS_SCAN_HW, &priv->status); + clear_bit(STATUS_SCAN_ABORTING, &priv->status); + iwl_legacy_complete_scan(priv, true); +} + +static void iwl_legacy_do_scan_abort(struct iwl_priv *priv) +{ + int ret; + + lockdep_assert_held(&priv->mutex); + + if (!test_bit(STATUS_SCANNING, &priv->status)) { + IWL_DEBUG_SCAN(priv, "Not performing scan to abort\n"); + return; + } + + if (test_and_set_bit(STATUS_SCAN_ABORTING, &priv->status)) { + IWL_DEBUG_SCAN(priv, "Scan abort in progress\n"); + return; + } + + ret = iwl_legacy_send_scan_abort(priv); + if (ret) { + IWL_DEBUG_SCAN(priv, "Send scan abort failed %d\n", ret); + iwl_legacy_force_scan_end(priv); + } else + IWL_DEBUG_SCAN(priv, "Sucessfully send scan abort\n"); +} + +/** + * iwl_scan_cancel - Cancel any currently executing HW scan + */ +int iwl_legacy_scan_cancel(struct iwl_priv *priv) +{ + IWL_DEBUG_SCAN(priv, "Queuing abort scan\n"); + queue_work(priv->workqueue, &priv->abort_scan); + return 0; +} +EXPORT_SYMBOL(iwl_legacy_scan_cancel); + +/** + * iwl_legacy_scan_cancel_timeout - Cancel any currently executing HW scan + * @ms: amount of time to wait (in milliseconds) for scan to abort + * + */ +int iwl_legacy_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(ms); + + lockdep_assert_held(&priv->mutex); + + IWL_DEBUG_SCAN(priv, "Scan cancel timeout\n"); + + iwl_legacy_do_scan_abort(priv); + + while (time_before_eq(jiffies, timeout)) { + if (!test_bit(STATUS_SCAN_HW, &priv->status)) + break; + msleep(20); + } + + return test_bit(STATUS_SCAN_HW, &priv->status); +} +EXPORT_SYMBOL(iwl_legacy_scan_cancel_timeout); + +/* Service response to REPLY_SCAN_CMD (0x80) */ +static void iwl_legacy_rx_reply_scan(struct iwl_priv *priv, + struct iwl_rx_mem_buffer *rxb) +{ +#ifdef CONFIG_IWLWIFI_LEGACY_DEBUG + struct iwl_rx_packet *pkt = rxb_addr(rxb); + struct iwl_scanreq_notification *notif = + (struct iwl_scanreq_notification *)pkt->u.raw; + + IWL_DEBUG_SCAN(priv, "Scan request status = 0x%x\n", notif->status); +#endif +} + +/* Service SCAN_START_NOTIFICATION (0x82) */ +static void iwl_legacy_rx_scan_start_notif(struct iwl_priv *priv, + struct iwl_rx_mem_buffer *rxb) +{ + struct iwl_rx_packet *pkt = rxb_addr(rxb); + struct iwl_scanstart_notification *notif = + (struct iwl_scanstart_notification *)pkt->u.raw; + priv->scan_start_tsf = le32_to_cpu(notif->tsf_low); + IWL_DEBUG_SCAN(priv, "Scan start: " + "%d [802.11%s] " + "(TSF: 0x%08X:%08X) - %d (beacon timer %u)\n", + notif->channel, + notif->band ? "bg" : "a", + le32_to_cpu(notif->tsf_high), + le32_to_cpu(notif->tsf_low), + notif->status, notif->beacon_timer); +} + +/* Service SCAN_RESULTS_NOTIFICATION (0x83) */ +static void iwl_legacy_rx_scan_results_notif(struct iwl_priv *priv, + struct iwl_rx_mem_buffer *rxb) +{ +#ifdef CONFIG_IWLWIFI_LEGACY_DEBUG + struct iwl_rx_packet *pkt = rxb_addr(rxb); + struct iwl_scanresults_notification *notif = + (struct iwl_scanresults_notification *)pkt->u.raw; + + IWL_DEBUG_SCAN(priv, "Scan ch.res: " + "%d [802.11%s] " + "(TSF: 0x%08X:%08X) - %d " + "elapsed=%lu usec\n", + notif->channel, + notif->band ? "bg" : "a", + le32_to_cpu(notif->tsf_high), + le32_to_cpu(notif->tsf_low), + le32_to_cpu(notif->statistics[0]), + le32_to_cpu(notif->tsf_low) - priv->scan_start_tsf); +#endif +} + +/* Service SCAN_COMPLETE_NOTIFICATION (0x84) */ +static void iwl_legacy_rx_scan_complete_notif(struct iwl_priv *priv, + struct iwl_rx_mem_buffer *rxb) +{ + +#ifdef CONFIG_IWLWIFI_LEGACY_DEBUG + struct iwl_rx_packet *pkt = rxb_addr(rxb); + struct iwl_scancomplete_notification *scan_notif = (void *)pkt->u.raw; +#endif + + IWL_DEBUG_SCAN(priv, + "Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n", + scan_notif->scanned_channels, + scan_notif->tsf_low, + scan_notif->tsf_high, scan_notif->status); + + /* The HW is no longer scanning */ + clear_bit(STATUS_SCAN_HW, &priv->status); + + IWL_DEBUG_SCAN(priv, "Scan on %sGHz took %dms\n", + (priv->scan_band == IEEE80211_BAND_2GHZ) ? "2.4" : "5.2", + jiffies_to_msecs(jiffies - priv->scan_start)); + + queue_work(priv->workqueue, &priv->scan_completed); +} + +void iwl_legacy_setup_rx_scan_handlers(struct iwl_priv *priv) +{ + /* scan handlers */ + priv->rx_handlers[REPLY_SCAN_CMD] = iwl_legacy_rx_reply_scan; + priv->rx_handlers[SCAN_START_NOTIFICATION] = + iwl_legacy_rx_scan_start_notif; + priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] = + iwl_legacy_rx_scan_results_notif; + priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] = + iwl_legacy_rx_scan_complete_notif; +} +EXPORT_SYMBOL(iwl_legacy_setup_rx_scan_handlers); + +inline u16 iwl_legacy_get_active_dwell_time(struct iwl_priv *priv, + enum ieee80211_band band, + u8 n_probes) +{ + if (band == IEEE80211_BAND_5GHZ) + return IWL_ACTIVE_DWELL_TIME_52 + + IWL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1); + else + return IWL_ACTIVE_DWELL_TIME_24 + + IWL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1); +} +EXPORT_SYMBOL(iwl_legacy_get_active_dwell_time); + +u16 iwl_legacy_get_passive_dwell_time(struct iwl_priv *priv, + enum ieee80211_band band, + struct ieee80211_vif *vif) +{ + struct iwl_rxon_context *ctx; + u16 passive = (band == IEEE80211_BAND_2GHZ) ? + IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_24 : + IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_52; + + if (iwl_legacy_is_any_associated(priv)) { + /* + * If we're associated, we clamp the maximum passive + * dwell time to be 98% of the smallest beacon interval + * (minus 2 * channel tune time) + */ + for_each_context(priv, ctx) { + u16 value; + + if (!iwl_legacy_is_associated_ctx(ctx)) + continue; + value = ctx->vif ? ctx->vif->bss_conf.beacon_int : 0; + if ((value > IWL_PASSIVE_DWELL_BASE) || !value) + value = IWL_PASSIVE_DWELL_BASE; + value = (value * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2; + passive = min(value, passive); + } + } + + return passive; +} +EXPORT_SYMBOL(iwl_legacy_get_passive_dwell_time); + +void iwl_legacy_init_scan_params(struct iwl_priv *priv) +{ + u8 ant_idx = fls(priv->hw_params.valid_tx_ant) - 1; + if (!priv->scan_tx_ant[IEEE80211_BAND_5GHZ]) + priv->scan_tx_ant[IEEE80211_BAND_5GHZ] = ant_idx; + if (!priv->scan_tx_ant[IEEE80211_BAND_2GHZ]) + priv->scan_tx_ant[IEEE80211_BAND_2GHZ] = ant_idx; +} +EXPORT_SYMBOL(iwl_legacy_init_scan_params); + +static int __must_check iwl_legacy_scan_initiate(struct iwl_priv *priv, + struct ieee80211_vif *vif, + bool internal, + enum ieee80211_band band) +{ + int ret; + + lockdep_assert_held(&priv->mutex); + + if (WARN_ON(!priv->cfg->ops->utils->request_scan)) + return -EOPNOTSUPP; + + cancel_delayed_work(&priv->scan_check); + + if (!iwl_legacy_is_ready_rf(priv)) { + IWL_WARN(priv, "Request scan called when driver not ready.\n"); + return -EIO; + } + + if (test_bit(STATUS_SCAN_HW, &priv->status)) { + IWL_DEBUG_SCAN(priv, + "Multiple concurrent scan requests in parallel.\n"); + return -EBUSY; + } + + if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) { + IWL_DEBUG_SCAN(priv, "Scan request while abort pending.\n"); + return -EBUSY; + } + + IWL_DEBUG_SCAN(priv, "Starting %sscan...\n", + internal ? "internal short " : ""); + + set_bit(STATUS_SCANNING, &priv->status); + priv->is_internal_short_scan = internal; + priv->scan_start = jiffies; + priv->scan_band = band; + + ret = priv->cfg->ops->utils->request_scan(priv, vif); + if (ret) { + clear_bit(STATUS_SCANNING, &priv->status); + priv->is_internal_short_scan = false; + return ret; + } + + queue_delayed_work(priv->workqueue, &priv->scan_check, + IWL_SCAN_CHECK_WATCHDOG); + + return 0; +} + +int iwl_legacy_mac_hw_scan(struct ieee80211_hw *hw, + struct ieee80211_vif *vif, + struct cfg80211_scan_request *req) +{ + struct iwl_priv *priv = hw->priv; + int ret; + + IWL_DEBUG_MAC80211(priv, "enter\n"); + + if (req->n_channels == 0) + return -EINVAL; + + mutex_lock(&priv->mutex); + + if (test_bit(STATUS_SCANNING, &priv->status) && + !priv->is_internal_short_scan) { + IWL_DEBUG_SCAN(priv, "Scan already in progress.\n"); + ret = -EAGAIN; + goto out_unlock; + } + + /* mac80211 will only ask for one band at a time */ + priv->scan_request = req; + priv->scan_vif = vif; + + /* + * If an internal scan is in progress, just set + * up the scan_request as per above. + */ + if (priv->is_internal_short_scan) { + IWL_DEBUG_SCAN(priv, "SCAN request during internal scan\n"); + ret = 0; + } else + ret = iwl_legacy_scan_initiate(priv, vif, false, + req->channels[0]->band); + + IWL_DEBUG_MAC80211(priv, "leave\n"); + +out_unlock: + mutex_unlock(&priv->mutex); + + return ret; +} +EXPORT_SYMBOL(iwl_legacy_mac_hw_scan); + +/* + * internal short scan, this function should only been called while associated. + * It will reset and tune the radio to prevent possible RF related problem + */ +void iwl_legacy_internal_short_hw_scan(struct iwl_priv *priv) +{ + queue_work(priv->workqueue, &priv->start_internal_scan); +} + +static void iwl_legacy_bg_start_internal_scan(struct work_struct *work) +{ + struct iwl_priv *priv = + container_of(work, struct iwl_priv, start_internal_scan); + + IWL_DEBUG_SCAN(priv, "Start internal scan\n"); + + mutex_lock(&priv->mutex); + + if (priv->is_internal_short_scan == true) { + IWL_DEBUG_SCAN(priv, "Internal scan already in progress\n"); + goto unlock; + } + + if (test_bit(STATUS_SCANNING, &priv->status)) { + IWL_DEBUG_SCAN(priv, "Scan already in progress.\n"); + goto unlock; + } + + if (iwl_legacy_scan_initiate(priv, NULL, true, priv->band)) + IWL_DEBUG_SCAN(priv, "failed to start internal short scan\n"); + unlock: + mutex_unlock(&priv->mutex); +} + +static void iwl_legacy_bg_scan_check(struct work_struct *data) +{ + struct iwl_priv *priv = + container_of(data, struct iwl_priv, scan_check.work); + + IWL_DEBUG_SCAN(priv, "Scan check work\n"); + + /* Since we are here firmware does not finish scan and + * most likely is in bad shape, so we don't bother to + * send abort command, just force scan complete to mac80211 */ + mutex_lock(&priv->mutex); + iwl_legacy_force_scan_end(priv); + mutex_unlock(&priv->mutex); +} + +/** + * iwl_legacy_fill_probe_req - fill in all required fields and IE for probe request + */ + +u16 +iwl_legacy_fill_probe_req(struct iwl_priv *priv, struct ieee80211_mgmt *frame, + const u8 *ta, const u8 *ies, int ie_len, int left) +{ + int len = 0; + u8 *pos = NULL; + + /* Make sure there is enough space for the probe request, + * two mandatory IEs and the data */ + left -= 24; + if (left < 0) + return 0; + + frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ); + memcpy(frame->da, iwlegacy_bcast_addr, ETH_ALEN); + memcpy(frame->sa, ta, ETH_ALEN); + memcpy(frame->bssid, iwlegacy_bcast_addr, ETH_ALEN); + frame->seq_ctrl = 0; + + len += 24; + + /* ...next IE... */ + pos = &frame->u.probe_req.variable[0]; + + /* fill in our indirect SSID IE */ + left -= 2; + if (left < 0) + return 0; + *pos++ = WLAN_EID_SSID; + *pos++ = 0; + + len += 2; + + if (WARN_ON(left < ie_len)) + return len; + + if (ies && ie_len) { + memcpy(pos, ies, ie_len); + len += ie_len; + } + + return (u16)len; +} +EXPORT_SYMBOL(iwl_legacy_fill_probe_req); + +static void iwl_legacy_bg_abort_scan(struct work_struct *work) +{ + struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan); + + IWL_DEBUG_SCAN(priv, "Abort scan work\n"); + + /* We keep scan_check work queued in case when firmware will not + * report back scan completed notification */ + mutex_lock(&priv->mutex); + iwl_legacy_scan_cancel_timeout(priv, 200); + mutex_unlock(&priv->mutex); +} + +static void iwl_legacy_bg_scan_completed(struct work_struct *work) +{ + struct iwl_priv *priv = + container_of(work, struct iwl_priv, scan_completed); + bool aborted; + + IWL_DEBUG_SCAN(priv, "Completed %sscan.\n", + priv->is_internal_short_scan ? "internal short " : ""); + + cancel_delayed_work(&priv->scan_check); + + mutex_lock(&priv->mutex); + + aborted = test_and_clear_bit(STATUS_SCAN_ABORTING, &priv->status); + if (aborted) + IWL_DEBUG_SCAN(priv, "Aborted scan completed.\n"); + + if (!test_and_clear_bit(STATUS_SCANNING, &priv->status)) { + IWL_DEBUG_SCAN(priv, "Scan already completed.\n"); + goto out_settings; + } + + if (priv->is_internal_short_scan && !aborted) { + int err; + + /* Check if mac80211 requested scan during our internal scan */ + if (priv->scan_request == NULL) + goto out_complete; + + /* If so request a new scan */ + err = iwl_legacy_scan_initiate(priv, priv->scan_vif, false, + priv->scan_request->channels[0]->band); + if (err) { + IWL_DEBUG_SCAN(priv, + "failed to initiate pending scan: %d\n", err); + aborted = true; + goto out_complete; + } + + goto out; + } + +out_complete: + iwl_legacy_complete_scan(priv, aborted); + +out_settings: + /* Can we still talk to firmware ? */ + if (!iwl_legacy_is_ready_rf(priv)) + goto out; + + /* + * We do not commit power settings while scan is pending, + * do it now if the settings changed. + */ + iwl_legacy_power_set_mode(priv, &priv->power_data.sleep_cmd_next, + false); + iwl_legacy_set_tx_power(priv, priv->tx_power_next, false); + + priv->cfg->ops->utils->post_scan(priv); + +out: + mutex_unlock(&priv->mutex); +} + +void iwl_legacy_setup_scan_deferred_work(struct iwl_priv *priv) +{ + INIT_WORK(&priv->scan_completed, iwl_legacy_bg_scan_completed); + INIT_WORK(&priv->abort_scan, iwl_legacy_bg_abort_scan); + INIT_WORK(&priv->start_internal_scan, + iwl_legacy_bg_start_internal_scan); + INIT_DELAYED_WORK(&priv->scan_check, iwl_legacy_bg_scan_check); +} +EXPORT_SYMBOL(iwl_legacy_setup_scan_deferred_work); + +void iwl_legacy_cancel_scan_deferred_work(struct iwl_priv *priv) +{ + cancel_work_sync(&priv->start_internal_scan); + cancel_work_sync(&priv->abort_scan); + cancel_work_sync(&priv->scan_completed); + + if (cancel_delayed_work_sync(&priv->scan_check)) { + mutex_lock(&priv->mutex); + iwl_legacy_force_scan_end(priv); + mutex_unlock(&priv->mutex); + } +} +EXPORT_SYMBOL(iwl_legacy_cancel_scan_deferred_work); |