diff options
Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-scan.c')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-scan.c | 931 |
1 files changed, 931 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-scan.c b/drivers/net/wireless/iwlwifi/iwl-scan.c new file mode 100644 index 000000000000..efc750d2fc5c --- /dev/null +++ b/drivers/net/wireless/iwlwifi/iwl-scan.c @@ -0,0 +1,931 @@ +/****************************************************************************** + * + * GPL LICENSE SUMMARY + * + * Copyright(c) 2008 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: + * Tomas Winkler <tomas.winkler@intel.com> + * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497 + *****************************************************************************/ +#include <net/mac80211.h> +#include <linux/etherdevice.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 faster active scanning, scan will move to the next channel if fewer than + * PLCP_QUIET_THRESH packets are heard on this channel within + * ACTIVE_QUIET_TIME after sending probe request. This shortens the dwell + * time if it's a quiet channel (nothing responded to our probe, and there's + * no other traffic). + * Disable "quiet" feature by setting PLCP_QUIET_THRESH to 0. */ +#define IWL_PLCP_QUIET_THRESH __constant_cpu_to_le16(1) /* packets */ +#define IWL_ACTIVE_QUIET_TIME __constant_cpu_to_le16(10) /* msec */ + +/* 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 + +#define IWL_SCAN_PROBE_MASK(n) cpu_to_le32((BIT(n) | (BIT(n) - BIT(1)))) + + +static int scan_tx_ant[3] = { + RATE_MCS_ANT_A_MSK, RATE_MCS_ANT_B_MSK, RATE_MCS_ANT_C_MSK +}; + + + +static int iwl_is_empty_essid(const char *essid, int essid_len) +{ + /* Single white space is for Linksys APs */ + if (essid_len == 1 && essid[0] == ' ') + return 1; + + /* Otherwise, if the entire essid is 0, we assume it is hidden */ + while (essid_len) { + essid_len--; + if (essid[essid_len] != '\0') + return 0; + } + + return 1; +} + + + +const char *iwl_escape_essid(const char *essid, u8 essid_len) +{ + static char escaped[IW_ESSID_MAX_SIZE * 2 + 1]; + const char *s = essid; + char *d = escaped; + + if (iwl_is_empty_essid(essid, essid_len)) { + memcpy(escaped, "<hidden>", sizeof("<hidden>")); + return escaped; + } + + essid_len = min(essid_len, (u8) IW_ESSID_MAX_SIZE); + while (essid_len--) { + if (*s == '\0') { + *d++ = '\\'; + *d++ = '0'; + s++; + } else + *d++ = *s++; + } + *d = '\0'; + return escaped; +} +EXPORT_SYMBOL(iwl_escape_essid); + +/** + * iwl_scan_cancel - Cancel any currently executing HW scan + * + * NOTE: priv->mutex is not required before calling this function + */ +int iwl_scan_cancel(struct iwl_priv *priv) +{ + if (!test_bit(STATUS_SCAN_HW, &priv->status)) { + clear_bit(STATUS_SCANNING, &priv->status); + return 0; + } + + if (test_bit(STATUS_SCANNING, &priv->status)) { + if (!test_bit(STATUS_SCAN_ABORTING, &priv->status)) { + IWL_DEBUG_SCAN("Queuing scan abort.\n"); + set_bit(STATUS_SCAN_ABORTING, &priv->status); + queue_work(priv->workqueue, &priv->abort_scan); + + } else + IWL_DEBUG_SCAN("Scan abort already in progress.\n"); + + return test_bit(STATUS_SCANNING, &priv->status); + } + + return 0; +} +EXPORT_SYMBOL(iwl_scan_cancel); +/** + * iwl_scan_cancel_timeout - Cancel any currently executing HW scan + * @ms: amount of time to wait (in milliseconds) for scan to abort + * + * NOTE: priv->mutex must be held before calling this function + */ +int iwl_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms) +{ + unsigned long now = jiffies; + int ret; + + ret = iwl_scan_cancel(priv); + if (ret && ms) { + mutex_unlock(&priv->mutex); + while (!time_after(jiffies, now + msecs_to_jiffies(ms)) && + test_bit(STATUS_SCANNING, &priv->status)) + msleep(1); + mutex_lock(&priv->mutex); + + return test_bit(STATUS_SCANNING, &priv->status); + } + + return ret; +} +EXPORT_SYMBOL(iwl_scan_cancel_timeout); + +static int iwl_send_scan_abort(struct iwl_priv *priv) +{ + int ret = 0; + struct iwl_rx_packet *res; + struct iwl_host_cmd cmd = { + .id = REPLY_SCAN_ABORT_CMD, + .meta.flags = CMD_WANT_SKB, + }; + + /* If there isn't a scan actively going on in the hardware + * then we are in between scan bands and not actually + * actively scanning, so don't send the abort command */ + if (!test_bit(STATUS_SCAN_HW, &priv->status)) { + clear_bit(STATUS_SCAN_ABORTING, &priv->status); + return 0; + } + + ret = iwl_send_cmd_sync(priv, &cmd); + if (ret) { + clear_bit(STATUS_SCAN_ABORTING, &priv->status); + return ret; + } + + res = (struct iwl_rx_packet *)cmd.meta.u.skb->data; + if (res->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_INFO("SCAN_ABORT returned %d.\n", res->u.status); + clear_bit(STATUS_SCAN_ABORTING, &priv->status); + clear_bit(STATUS_SCAN_HW, &priv->status); + } + + dev_kfree_skb_any(cmd.meta.u.skb); + + return ret; +} + + +/* Service response to REPLY_SCAN_CMD (0x80) */ +static void iwl_rx_reply_scan(struct iwl_priv *priv, + struct iwl_rx_mem_buffer *rxb) +{ +#ifdef CONFIG_IWLWIFI_DEBUG + struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data; + struct iwl_scanreq_notification *notif = + (struct iwl_scanreq_notification *)pkt->u.raw; + + IWL_DEBUG_RX("Scan request status = 0x%x\n", notif->status); +#endif +} + +/* Service SCAN_START_NOTIFICATION (0x82) */ +static void iwl_rx_scan_start_notif(struct iwl_priv *priv, + struct iwl_rx_mem_buffer *rxb) +{ + struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data; + 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("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_rx_scan_results_notif(struct iwl_priv *priv, + struct iwl_rx_mem_buffer *rxb) +{ +#ifdef CONFIG_IWLWIFI_DEBUG + struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data; + struct iwl_scanresults_notification *notif = + (struct iwl_scanresults_notification *)pkt->u.raw; + + IWL_DEBUG_SCAN("Scan ch.res: " + "%d [802.11%s] " + "(TSF: 0x%08X:%08X) - %d " + "elapsed=%lu usec (%dms since last)\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, + jiffies_to_msecs(elapsed_jiffies + (priv->last_scan_jiffies, jiffies))); +#endif + + priv->last_scan_jiffies = jiffies; + priv->next_scan_jiffies = 0; +} + +/* Service SCAN_COMPLETE_NOTIFICATION (0x84) */ +static void iwl_rx_scan_complete_notif(struct iwl_priv *priv, + struct iwl_rx_mem_buffer *rxb) +{ + struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data; + struct iwl_scancomplete_notification *scan_notif = (void *)pkt->u.raw; + + IWL_DEBUG_SCAN("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); + + /* The scan completion notification came in, so kill that timer... */ + cancel_delayed_work(&priv->scan_check); + + IWL_DEBUG_INFO("Scan pass on %sGHz took %dms\n", + (priv->scan_bands & BIT(IEEE80211_BAND_2GHZ)) ? + "2.4" : "5.2", + jiffies_to_msecs(elapsed_jiffies + (priv->scan_pass_start, jiffies))); + + /* Remove this scanned band from the list of pending + * bands to scan, band G precedes A in order of scanning + * as seen in iwl_bg_request_scan */ + if (priv->scan_bands & BIT(IEEE80211_BAND_2GHZ)) + priv->scan_bands &= ~BIT(IEEE80211_BAND_2GHZ); + else if (priv->scan_bands & BIT(IEEE80211_BAND_5GHZ)) + priv->scan_bands &= ~BIT(IEEE80211_BAND_5GHZ); + + /* If a request to abort was given, or the scan did not succeed + * then we reset the scan state machine and terminate, + * re-queuing another scan if one has been requested */ + if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) { + IWL_DEBUG_INFO("Aborted scan completed.\n"); + clear_bit(STATUS_SCAN_ABORTING, &priv->status); + } else { + /* If there are more bands on this scan pass reschedule */ + if (priv->scan_bands) + goto reschedule; + } + + priv->last_scan_jiffies = jiffies; + priv->next_scan_jiffies = 0; + IWL_DEBUG_INFO("Setting scan to off\n"); + + clear_bit(STATUS_SCANNING, &priv->status); + + IWL_DEBUG_INFO("Scan took %dms\n", + jiffies_to_msecs(elapsed_jiffies(priv->scan_start, jiffies))); + + queue_work(priv->workqueue, &priv->scan_completed); + + return; + +reschedule: + priv->scan_pass_start = jiffies; + queue_work(priv->workqueue, &priv->request_scan); +} + +void iwl_setup_rx_scan_handlers(struct iwl_priv *priv) +{ + /* scan handlers */ + priv->rx_handlers[REPLY_SCAN_CMD] = iwl_rx_reply_scan; + priv->rx_handlers[SCAN_START_NOTIFICATION] = iwl_rx_scan_start_notif; + priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] = + iwl_rx_scan_results_notif; + priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] = + iwl_rx_scan_complete_notif; +} +EXPORT_SYMBOL(iwl_setup_rx_scan_handlers); + +static inline u16 iwl_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); +} + +static u16 iwl_get_passive_dwell_time(struct iwl_priv *priv, + enum ieee80211_band band) +{ + 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_is_associated(priv)) { + /* If we're associated, we clamp the maximum passive + * dwell time to be 98% of the beacon interval (minus + * 2 * channel tune time) */ + passive = priv->beacon_int; + if ((passive > IWL_PASSIVE_DWELL_BASE) || !passive) + passive = IWL_PASSIVE_DWELL_BASE; + passive = (passive * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2; + } + + return passive; +} + +static int iwl_get_channels_for_scan(struct iwl_priv *priv, + enum ieee80211_band band, + u8 is_active, u8 n_probes, + struct iwl_scan_channel *scan_ch) +{ + const struct ieee80211_channel *channels = NULL; + const struct ieee80211_supported_band *sband; + const struct iwl_channel_info *ch_info; + u16 passive_dwell = 0; + u16 active_dwell = 0; + int added, i; + u16 channel; + + sband = iwl_get_hw_mode(priv, band); + if (!sband) + return 0; + + channels = sband->channels; + + active_dwell = iwl_get_active_dwell_time(priv, band, n_probes); + passive_dwell = iwl_get_passive_dwell_time(priv, band); + + if (passive_dwell <= active_dwell) + passive_dwell = active_dwell + 1; + + for (i = 0, added = 0; i < sband->n_channels; i++) { + if (channels[i].flags & IEEE80211_CHAN_DISABLED) + continue; + + channel = + ieee80211_frequency_to_channel(channels[i].center_freq); + scan_ch->channel = cpu_to_le16(channel); + + ch_info = iwl_get_channel_info(priv, band, channel); + if (!is_channel_valid(ch_info)) { + IWL_DEBUG_SCAN("Channel %d is INVALID for this band.\n", + channel); + continue; + } + + if (!is_active || is_channel_passive(ch_info) || + (channels[i].flags & IEEE80211_CHAN_PASSIVE_SCAN)) + scan_ch->type = SCAN_CHANNEL_TYPE_PASSIVE; + else + scan_ch->type = SCAN_CHANNEL_TYPE_ACTIVE; + + if ((scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) && n_probes) + scan_ch->type |= IWL_SCAN_PROBE_MASK(n_probes); + + scan_ch->active_dwell = cpu_to_le16(active_dwell); + scan_ch->passive_dwell = cpu_to_le16(passive_dwell); + + /* Set txpower levels to defaults */ + scan_ch->dsp_atten = 110; + + /* NOTE: if we were doing 6Mb OFDM for scans we'd use + * power level: + * scan_ch->tx_gain = ((1 << 5) | (2 << 3)) | 3; + */ + if (band == IEEE80211_BAND_5GHZ) + scan_ch->tx_gain = ((1 << 5) | (3 << 3)) | 3; + else + scan_ch->tx_gain = ((1 << 5) | (5 << 3)); + + IWL_DEBUG_SCAN("Scanning ch=%d prob=0x%X [%s %d]\n", + channel, le32_to_cpu(scan_ch->type), + (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ? + "ACTIVE" : "PASSIVE", + (scan_ch->type & SCAN_CHANNEL_TYPE_ACTIVE) ? + active_dwell : passive_dwell); + + scan_ch++; + added++; + } + + IWL_DEBUG_SCAN("total channels to scan %d \n", added); + return added; +} + +void iwl_init_scan_params(struct iwl_priv *priv) +{ + if (!priv->scan_tx_ant[IEEE80211_BAND_5GHZ]) + priv->scan_tx_ant[IEEE80211_BAND_5GHZ] = RATE_MCS_ANT_INIT_IND; + if (!priv->scan_tx_ant[IEEE80211_BAND_2GHZ]) + priv->scan_tx_ant[IEEE80211_BAND_2GHZ] = RATE_MCS_ANT_INIT_IND; +} + +int iwl_scan_initiate(struct iwl_priv *priv) +{ + if (priv->iw_mode == IEEE80211_IF_TYPE_AP) { + IWL_ERROR("APs don't scan.\n"); + return 0; + } + + if (!iwl_is_ready_rf(priv)) { + IWL_DEBUG_SCAN("Aborting scan due to not ready.\n"); + return -EIO; + } + + if (test_bit(STATUS_SCANNING, &priv->status)) { + IWL_DEBUG_SCAN("Scan already in progress.\n"); + return -EAGAIN; + } + + if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) { + IWL_DEBUG_SCAN("Scan request while abort pending. " + "Queuing.\n"); + return -EAGAIN; + } + + IWL_DEBUG_INFO("Starting scan...\n"); + if (priv->cfg->sku & IWL_SKU_G) + priv->scan_bands |= BIT(IEEE80211_BAND_2GHZ); + if (priv->cfg->sku & IWL_SKU_A) + priv->scan_bands |= BIT(IEEE80211_BAND_5GHZ); + set_bit(STATUS_SCANNING, &priv->status); + priv->scan_start = jiffies; + priv->scan_pass_start = priv->scan_start; + + queue_work(priv->workqueue, &priv->request_scan); + + return 0; +} +EXPORT_SYMBOL(iwl_scan_initiate); + +#define IWL_SCAN_CHECK_WATCHDOG (7 * HZ) + +static void iwl_bg_scan_check(struct work_struct *data) +{ + struct iwl_priv *priv = + container_of(data, struct iwl_priv, scan_check.work); + + if (test_bit(STATUS_EXIT_PENDING, &priv->status)) + return; + + mutex_lock(&priv->mutex); + if (test_bit(STATUS_SCANNING, &priv->status) || + test_bit(STATUS_SCAN_ABORTING, &priv->status)) { + IWL_DEBUG(IWL_DL_SCAN, "Scan completion watchdog resetting " + "adapter (%dms)\n", + jiffies_to_msecs(IWL_SCAN_CHECK_WATCHDOG)); + + if (!test_bit(STATUS_EXIT_PENDING, &priv->status)) + iwl_send_scan_abort(priv); + } + mutex_unlock(&priv->mutex); +} +/** + * iwl_supported_rate_to_ie - fill in the supported rate in IE field + * + * return : set the bit for each supported rate insert in ie + */ +static u16 iwl_supported_rate_to_ie(u8 *ie, u16 supported_rate, + u16 basic_rate, int *left) +{ + u16 ret_rates = 0, bit; + int i; + u8 *cnt = ie; + u8 *rates = ie + 1; + + for (bit = 1, i = 0; i < IWL_RATE_COUNT; i++, bit <<= 1) { + if (bit & supported_rate) { + ret_rates |= bit; + rates[*cnt] = iwl_rates[i].ieee | + ((bit & basic_rate) ? 0x80 : 0x00); + (*cnt)++; + (*left)--; + if ((*left <= 0) || + (*cnt >= IWL_SUPPORTED_RATES_IE_LEN)) + break; + } + } + + return ret_rates; +} + + +static void iwl_ht_cap_to_ie(const struct ieee80211_supported_band *sband, + u8 *pos, int *left) +{ + struct ieee80211_ht_cap *ht_cap; + + if (!sband || !sband->ht_info.ht_supported) + return; + + if (*left < sizeof(struct ieee80211_ht_cap)) + return; + + *pos++ = sizeof(struct ieee80211_ht_cap); + ht_cap = (struct ieee80211_ht_cap *) pos; + + ht_cap->cap_info = cpu_to_le16(sband->ht_info.cap); + memcpy(ht_cap->supp_mcs_set, sband->ht_info.supp_mcs_set, 16); + ht_cap->ampdu_params_info = + (sband->ht_info.ampdu_factor & IEEE80211_HT_CAP_AMPDU_FACTOR) | + ((sband->ht_info.ampdu_density << 2) & + IEEE80211_HT_CAP_AMPDU_DENSITY); + *left -= sizeof(struct ieee80211_ht_cap); +} + +/** + * iwl_fill_probe_req - fill in all required fields and IE for probe request + */ + +static u16 iwl_fill_probe_req(struct iwl_priv *priv, + enum ieee80211_band band, + struct ieee80211_mgmt *frame, + int left) +{ + int len = 0; + u8 *pos = NULL; + u16 active_rates, ret_rates, cck_rates, active_rate_basic; + const struct ieee80211_supported_band *sband = + iwl_get_hw_mode(priv, band); + + + /* 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, iwl_bcast_addr, ETH_ALEN); + memcpy(frame->sa, priv->mac_addr, ETH_ALEN); + memcpy(frame->bssid, iwl_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; + + /* fill in supported rate */ + left -= 2; + if (left < 0) + return 0; + + *pos++ = WLAN_EID_SUPP_RATES; + *pos = 0; + + /* exclude 60M rate */ + active_rates = priv->rates_mask; + active_rates &= ~IWL_RATE_60M_MASK; + + active_rate_basic = active_rates & IWL_BASIC_RATES_MASK; + + cck_rates = IWL_CCK_RATES_MASK & active_rates; + ret_rates = iwl_supported_rate_to_ie(pos, cck_rates, + active_rate_basic, &left); + active_rates &= ~ret_rates; + + ret_rates = iwl_supported_rate_to_ie(pos, active_rates, + active_rate_basic, &left); + active_rates &= ~ret_rates; + + len += 2 + *pos; + pos += (*pos) + 1; + + if (active_rates == 0) + goto fill_end; + + /* fill in supported extended rate */ + /* ...next IE... */ + left -= 2; + if (left < 0) + return 0; + /* ... fill it in... */ + *pos++ = WLAN_EID_EXT_SUPP_RATES; + *pos = 0; + iwl_supported_rate_to_ie(pos, active_rates, active_rate_basic, &left); + if (*pos > 0) { + len += 2 + *pos; + pos += (*pos) + 1; + } else { + pos--; + } + + fill_end: + + left -= 2; + if (left < 0) + return 0; + + *pos++ = WLAN_EID_HT_CAPABILITY; + *pos = 0; + iwl_ht_cap_to_ie(sband, pos, &left); + if (*pos > 0) + len += 2 + *pos; + + return (u16)len; +} + +static u32 iwl_scan_tx_ant(struct iwl_priv *priv, enum ieee80211_band band) +{ + int i, ind; + + ind = priv->scan_tx_ant[band]; + for (i = 0; i < priv->hw_params.tx_chains_num; i++) { + ind = (ind+1) >= priv->hw_params.tx_chains_num ? 0 : ind+1; + if (priv->hw_params.valid_tx_ant & (1 << ind)) { + priv->scan_tx_ant[band] = ind; + break; + } + } + IWL_DEBUG_SCAN("select TX ANT = %c\n", 'A' + ind); + return scan_tx_ant[ind]; +} + + +static void iwl_bg_request_scan(struct work_struct *data) +{ + struct iwl_priv *priv = + container_of(data, struct iwl_priv, request_scan); + struct iwl_host_cmd cmd = { + .id = REPLY_SCAN_CMD, + .len = sizeof(struct iwl_scan_cmd), + .meta.flags = CMD_SIZE_HUGE, + }; + struct iwl_scan_cmd *scan; + struct ieee80211_conf *conf = NULL; + int ret = 0; + u32 tx_ant; + u16 cmd_len; + enum ieee80211_band band; + u8 n_probes = 2; + u8 rx_chain = 0x7; /* bitmap: ABC chains */ + + conf = ieee80211_get_hw_conf(priv->hw); + + mutex_lock(&priv->mutex); + + if (!iwl_is_ready(priv)) { + IWL_WARNING("request scan called when driver not ready.\n"); + goto done; + } + + /* Make sure the scan wasn't cancelled before this queued work + * was given the chance to run... */ + if (!test_bit(STATUS_SCANNING, &priv->status)) + goto done; + + /* This should never be called or scheduled if there is currently + * a scan active in the hardware. */ + if (test_bit(STATUS_SCAN_HW, &priv->status)) { + IWL_DEBUG_INFO("Multiple concurrent scan requests in parallel. " + "Ignoring second request.\n"); + ret = -EIO; + goto done; + } + + if (test_bit(STATUS_EXIT_PENDING, &priv->status)) { + IWL_DEBUG_SCAN("Aborting scan due to device shutdown\n"); + goto done; + } + + if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) { + IWL_DEBUG_HC("Scan request while abort pending. Queuing.\n"); + goto done; + } + + if (iwl_is_rfkill(priv)) { + IWL_DEBUG_HC("Aborting scan due to RF Kill activation\n"); + goto done; + } + + if (!test_bit(STATUS_READY, &priv->status)) { + IWL_DEBUG_HC("Scan request while uninitialized. Queuing.\n"); + goto done; + } + + if (!priv->scan_bands) { + IWL_DEBUG_HC("Aborting scan due to no requested bands\n"); + goto done; + } + + if (!priv->scan) { + priv->scan = kmalloc(sizeof(struct iwl_scan_cmd) + + IWL_MAX_SCAN_SIZE, GFP_KERNEL); + if (!priv->scan) { + ret = -ENOMEM; + goto done; + } + } + scan = priv->scan; + memset(scan, 0, sizeof(struct iwl_scan_cmd) + IWL_MAX_SCAN_SIZE); + + scan->quiet_plcp_th = IWL_PLCP_QUIET_THRESH; + scan->quiet_time = IWL_ACTIVE_QUIET_TIME; + + if (iwl_is_associated(priv)) { + u16 interval = 0; + u32 extra; + u32 suspend_time = 100; + u32 scan_suspend_time = 100; + unsigned long flags; + + IWL_DEBUG_INFO("Scanning while associated...\n"); + + spin_lock_irqsave(&priv->lock, flags); + interval = priv->beacon_int; + spin_unlock_irqrestore(&priv->lock, flags); + + scan->suspend_time = 0; + scan->max_out_time = cpu_to_le32(200 * 1024); + if (!interval) + interval = suspend_time; + + extra = (suspend_time / interval) << 22; + scan_suspend_time = (extra | + ((suspend_time % interval) * 1024)); + scan->suspend_time = cpu_to_le32(scan_suspend_time); + IWL_DEBUG_SCAN("suspend_time 0x%X beacon interval %d\n", + scan_suspend_time, interval); + } + + /* We should add the ability for user to lock to PASSIVE ONLY */ + if (priv->one_direct_scan) { + IWL_DEBUG_SCAN("Start direct scan for '%s'\n", + iwl_escape_essid(priv->direct_ssid, + priv->direct_ssid_len)); + scan->direct_scan[0].id = WLAN_EID_SSID; + scan->direct_scan[0].len = priv->direct_ssid_len; + memcpy(scan->direct_scan[0].ssid, + priv->direct_ssid, priv->direct_ssid_len); + n_probes++; + } else if (!iwl_is_associated(priv) && priv->essid_len) { + IWL_DEBUG_SCAN("Start direct scan for '%s' (not associated)\n", + iwl_escape_essid(priv->essid, priv->essid_len)); + scan->direct_scan[0].id = WLAN_EID_SSID; + scan->direct_scan[0].len = priv->essid_len; + memcpy(scan->direct_scan[0].ssid, priv->essid, priv->essid_len); + n_probes++; + } else { + IWL_DEBUG_SCAN("Start indirect scan.\n"); + } + + scan->tx_cmd.tx_flags = TX_CMD_FLG_SEQ_CTL_MSK; + scan->tx_cmd.sta_id = priv->hw_params.bcast_sta_id; + scan->tx_cmd.stop_time.life_time = TX_CMD_LIFE_TIME_INFINITE; + + + if (priv->scan_bands & BIT(IEEE80211_BAND_2GHZ)) { + band = IEEE80211_BAND_2GHZ; + scan->flags = RXON_FLG_BAND_24G_MSK | RXON_FLG_AUTO_DETECT_MSK; + tx_ant = iwl_scan_tx_ant(priv, band); + if (priv->active_rxon.flags & RXON_FLG_CHANNEL_MODE_PURE_40_MSK) + scan->tx_cmd.rate_n_flags = + iwl_hw_set_rate_n_flags(IWL_RATE_6M_PLCP, + tx_ant); + else + scan->tx_cmd.rate_n_flags = + iwl_hw_set_rate_n_flags(IWL_RATE_1M_PLCP, + tx_ant | + RATE_MCS_CCK_MSK); + scan->good_CRC_th = 0; + } else if (priv->scan_bands & BIT(IEEE80211_BAND_5GHZ)) { + band = IEEE80211_BAND_5GHZ; + tx_ant = iwl_scan_tx_ant(priv, band); + scan->tx_cmd.rate_n_flags = + iwl_hw_set_rate_n_flags(IWL_RATE_6M_PLCP, + tx_ant); + scan->good_CRC_th = IWL_GOOD_CRC_TH; + + /* Force use of chains B and C (0x6) for scan Rx for 4965 + * Avoid A (0x1) because of its off-channel reception on A-band. + * MIMO is not used here, but value is required */ + if ((priv->hw_rev & CSR_HW_REV_TYPE_MSK) == CSR_HW_REV_TYPE_4965) + rx_chain = 0x6; + } else { + IWL_WARNING("Invalid scan band count\n"); + goto done; + } + + scan->rx_chain = RXON_RX_CHAIN_DRIVER_FORCE_MSK | + cpu_to_le16((0x7 << RXON_RX_CHAIN_VALID_POS) | + (rx_chain << RXON_RX_CHAIN_FORCE_SEL_POS) | + (0x7 << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS)); + + cmd_len = iwl_fill_probe_req(priv, band, + (struct ieee80211_mgmt *)scan->data, + IWL_MAX_SCAN_SIZE - sizeof(*scan)); + + scan->tx_cmd.len = cpu_to_le16(cmd_len); + + if (priv->iw_mode == IEEE80211_IF_TYPE_MNTR) + scan->filter_flags = RXON_FILTER_PROMISC_MSK; + + scan->filter_flags |= (RXON_FILTER_ACCEPT_GRP_MSK | + RXON_FILTER_BCON_AWARE_MSK); + + scan->channel_count = + iwl_get_channels_for_scan(priv, band, 1, /* active */ + n_probes, + (void *)&scan->data[le16_to_cpu(scan->tx_cmd.len)]); + + if (scan->channel_count == 0) { + IWL_DEBUG_SCAN("channel count %d\n", scan->channel_count); + goto done; + } + + cmd.len += le16_to_cpu(scan->tx_cmd.len) + + scan->channel_count * sizeof(struct iwl_scan_channel); + cmd.data = scan; + scan->len = cpu_to_le16(cmd.len); + + set_bit(STATUS_SCAN_HW, &priv->status); + ret = iwl_send_cmd_sync(priv, &cmd); + if (ret) + goto done; + + queue_delayed_work(priv->workqueue, &priv->scan_check, + IWL_SCAN_CHECK_WATCHDOG); + + mutex_unlock(&priv->mutex); + return; + + done: + /* inform mac80211 scan aborted */ + queue_work(priv->workqueue, &priv->scan_completed); + mutex_unlock(&priv->mutex); +} + +static void iwl_bg_abort_scan(struct work_struct *work) +{ + struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan); + + if (!iwl_is_ready(priv)) + return; + + mutex_lock(&priv->mutex); + + set_bit(STATUS_SCAN_ABORTING, &priv->status); + iwl_send_scan_abort(priv); + + mutex_unlock(&priv->mutex); +} + +void iwl_setup_scan_deferred_work(struct iwl_priv *priv) +{ + /* FIXME: move here when resolved PENDING + * INIT_WORK(&priv->scan_completed, iwl_bg_scan_completed); */ + INIT_WORK(&priv->request_scan, iwl_bg_request_scan); + INIT_WORK(&priv->abort_scan, iwl_bg_abort_scan); + INIT_DELAYED_WORK(&priv->scan_check, iwl_bg_scan_check); +} +EXPORT_SYMBOL(iwl_setup_scan_deferred_work); + |
