drivers/net/wireless/iwlwifi/mvm/scan.c

   1 /******************************************************************************
   2  *
   3  * This file is provided under a dual BSD/GPLv2 license.  When using or
   4  * redistributing this file, you may do so under either license.
   5  *
   6  * GPL LICENSE SUMMARY
   7  *
   8  * Copyright(c) 2012 - 2013 Intel Corporation. All rights reserved.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of version 2 of the GNU General Public License as
  12  * published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
  22  * USA
  23  *
  24  * The full GNU General Public License is included in this distribution
  25  * in the file called LICENSE.GPL.
  26  *
  27  * Contact Information:
  28  *  Intel Linux Wireless <ilw@linux.intel.com>
  29  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  30  *
  31  * BSD LICENSE
  32  *
  33  * Copyright(c) 2012 - 2013 Intel Corporation. All rights reserved.
  34  * All rights reserved.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions
  38  * are met:
  39  *
  40  *  * Redistributions of source code must retain the above copyright
  41  *    notice, this list of conditions and the following disclaimer.
  42  *  * Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in
  44  *    the documentation and/or other materials provided with the
  45  *    distribution.
  46  *  * Neither the name Intel Corporation nor the names of its
  47  *    contributors may be used to endorse or promote products derived
  48  *    from this software without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  51  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  52  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  53  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  54  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  55  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  56  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  57  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  58  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  59  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  60  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  61  *
  62  *****************************************************************************/
  63
  64 #include <linux/etherdevice.h>
  65 #include <net/mac80211.h>
  66
  67 #include "mvm.h"
  68 #include "iwl-eeprom-parse.h"
  69 #include "fw-api-scan.h"
  70
  71 #define IWL_PLCP_QUIET_THRESH 1
  72 #define IWL_ACTIVE_QUIET_TIME 10
  73
  74 static inline __le16 iwl_mvm_scan_rx_chain(struct iwl_mvm *mvm)
  75 {
  76         u16 rx_chain;
  77         u8 rx_ant = mvm->nvm_data->valid_rx_ant;
  78
  79         rx_chain = rx_ant << PHY_RX_CHAIN_VALID_POS;
  80         rx_chain |= rx_ant << PHY_RX_CHAIN_FORCE_MIMO_SEL_POS;
  81         rx_chain |= rx_ant << PHY_RX_CHAIN_FORCE_SEL_POS;
  82         rx_chain |= 0x1 << PHY_RX_CHAIN_DRIVER_FORCE_POS;
  83         return cpu_to_le16(rx_chain);
  84 }
  85
  86 static inline __le32 iwl_mvm_scan_max_out_time(struct ieee80211_vif *vif)
  87 {
  88         if (vif->bss_conf.assoc)
  89                 return cpu_to_le32(200 * 1024);
  90         else
  91                 return 0;
  92 }
  93
  94 static inline __le32 iwl_mvm_scan_suspend_time(struct ieee80211_vif *vif)
  95 {
  96         if (vif->bss_conf.assoc)
  97                 return cpu_to_le32(vif->bss_conf.beacon_int);
  98         else
  99                 return 0;
 100 }
 101
 102 static inline __le32
 103 iwl_mvm_scan_rxon_flags(struct cfg80211_scan_request *req)
 104 {
 105         if (req->channels[0]->band == IEEE80211_BAND_2GHZ)
 106                 return cpu_to_le32(PHY_BAND_24);
 107         else
 108                 return cpu_to_le32(PHY_BAND_5);
 109 }
 110
 111 static inline __le32
 112 iwl_mvm_scan_rate_n_flags(struct iwl_mvm *mvm, enum ieee80211_band band,
 113                           bool no_cck)
 114 {
 115         u32 tx_ant;
 116
 117         mvm->scan_last_antenna_idx =
 118                 iwl_mvm_next_antenna(mvm, mvm->nvm_data->valid_tx_ant,
 119                                      mvm->scan_last_antenna_idx);
 120         tx_ant = BIT(mvm->scan_last_antenna_idx) << RATE_MCS_ANT_POS;
 121
 122         if (band == IEEE80211_BAND_2GHZ && !no_cck)
 123                 return cpu_to_le32(IWL_RATE_1M_PLCP | RATE_MCS_CCK_MSK |
 124                                    tx_ant);
 125         else
 126                 return cpu_to_le32(IWL_RATE_6M_PLCP | tx_ant);
 127 }
 128
 129 /*
 130  * We insert the SSIDs in an inverted order, because the FW will
 131  * invert it back. The most prioritized SSID, which is first in the
 132  * request list, is not copied here, but inserted directly to the probe
 133  * request.
 134  */
 135 static void iwl_mvm_scan_fill_ssids(struct iwl_scan_cmd *cmd,
 136                                     struct cfg80211_scan_request *req)
 137 {
 138         int fw_idx, req_idx;
 139
 140         fw_idx = 0;
 141         for (req_idx = req->n_ssids - 1; req_idx > 0; req_idx--) {
 142                 cmd->direct_scan[fw_idx].id = WLAN_EID_SSID;
 143                 cmd->direct_scan[fw_idx].len = req->ssids[req_idx].ssid_len;
 144                 memcpy(cmd->direct_scan[fw_idx].ssid,
 145                        req->ssids[req_idx].ssid,
 146                        req->ssids[req_idx].ssid_len);
 147         }
 148 }
 149
 150 /*
 151  * If req->n_ssids > 0, it means we should do an active scan.
 152  * In case of active scan w/o directed scan, we receive a zero-length SSID
 153  * just to notify that this scan is active and not passive.
 154  * In order to notify the FW of the number of SSIDs we wish to scan (including
 155  * the zero-length one), we need to set the corresponding bits in chan->type,
 156  * one for each SSID, and set the active bit (first).
 157  */
 158 static u16 iwl_mvm_get_active_dwell(enum ieee80211_band band, int n_ssids)
 159 {
 160         if (band == IEEE80211_BAND_2GHZ)
 161                 return 30  + 3 * (n_ssids + 1);
 162         return 20  + 2 * (n_ssids + 1);
 163 }
 164
 165 static u16 iwl_mvm_get_passive_dwell(enum ieee80211_band band)
 166 {
 167         return band == IEEE80211_BAND_2GHZ ? 100 + 20 : 100 + 10;
 168 }
 169
 170 static void iwl_mvm_scan_fill_channels(struct iwl_scan_cmd *cmd,
 171                                        struct cfg80211_scan_request *req)
 172 {
 173         u16 passive_dwell = iwl_mvm_get_passive_dwell(req->channels[0]->band);
 174         u16 active_dwell = iwl_mvm_get_active_dwell(req->channels[0]->band,
 175                                                     req->n_ssids);
 176         struct iwl_scan_channel *chan = (struct iwl_scan_channel *)
 177                 (cmd->data + le16_to_cpu(cmd->tx_cmd.len));
 178         int i;
 179         __le32 chan_type_value;
 180
 181         if (req->n_ssids > 0)
 182                 chan_type_value = cpu_to_le32(BIT(req->n_ssids + 1) - 1);
 183         else
 184                 chan_type_value = SCAN_CHANNEL_TYPE_PASSIVE;
 185
 186         for (i = 0; i < cmd->channel_count; i++) {
 187                 chan->channel = cpu_to_le16(req->channels[i]->hw_value);
 188                 if (req->channels[i]->flags & IEEE80211_CHAN_PASSIVE_SCAN)
 189                         chan->type = SCAN_CHANNEL_TYPE_PASSIVE;
 190                 else
 191                         chan->type = chan_type_value;
 192                 chan->active_dwell = cpu_to_le16(active_dwell);
 193                 chan->passive_dwell = cpu_to_le16(passive_dwell);
 194                 chan->iteration_count = cpu_to_le16(1);
 195                 chan++;
 196         }
 197 }
 198
 199 /*
 200  * Fill in probe request with the following parameters:
 201  * TA is our vif HW address, which mac80211 ensures we have.
 202  * Packet is broadcasted, so this is both SA and DA.
 203  * The probe request IE is made out of two: first comes the most prioritized
 204  * SSID if a directed scan is requested. Second comes whatever extra
 205  * information was given to us as the scan request IE.
 206  */
 207 static u16 iwl_mvm_fill_probe_req(struct ieee80211_mgmt *frame, const u8 *ta,
 208                                   int n_ssids, const u8 *ssid, int ssid_len,
 209                                   const u8 *ie, int ie_len,
 210                                   int left)
 211 {
 212         int len = 0;
 213         u8 *pos = NULL;
 214
 215         /* Make sure there is enough space for the probe request,
 216          * two mandatory IEs and the data */
 217         left -= 24;
 218         if (left < 0)
 219                 return 0;
 220
 221         frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
 222         eth_broadcast_addr(frame->da);
 223         memcpy(frame->sa, ta, ETH_ALEN);
 224         eth_broadcast_addr(frame->bssid);
 225         frame->seq_ctrl = 0;
 226
 227         len += 24;
 228
 229         /* for passive scans, no need to fill anything */
 230         if (n_ssids == 0)
 231                 return (u16)len;
 232
 233         /* points to the payload of the request */
 234         pos = &frame->u.probe_req.variable[0];
 235
 236         /* fill in our SSID IE */
 237         left -= ssid_len + 2;
 238         if (left < 0)
 239                 return 0;
 240         *pos++ = WLAN_EID_SSID;
 241         *pos++ = ssid_len;
 242         if (ssid && ssid_len) { /* ssid_len may be == 0 even if ssid is valid */
 243                 memcpy(pos, ssid, ssid_len);
 244                 pos += ssid_len;
 245         }
 246
 247         len += ssid_len + 2;
 248
 249         if (WARN_ON(left < ie_len))
 250                 return len;
 251
 252         if (ie && ie_len) {
 253                 memcpy(pos, ie, ie_len);
 254                 len += ie_len;
 255         }
 256
 257         return (u16)len;
 258 }
 259
 260 int iwl_mvm_scan_request(struct iwl_mvm *mvm,
 261                          struct ieee80211_vif *vif,
 262                          struct cfg80211_scan_request *req)
 263 {
 264         struct iwl_host_cmd hcmd = {
 265                 .id = SCAN_REQUEST_CMD,
 266                 .len = { 0, },
 267                 .data = { mvm->scan_cmd, },
 268                 .flags = CMD_SYNC,
 269                 .dataflags = { IWL_HCMD_DFL_NOCOPY, },
 270         };
 271         struct iwl_scan_cmd *cmd = mvm->scan_cmd;
 272         int ret;
 273         u32 status;
 274         int ssid_len = 0;
 275         u8 *ssid = NULL;
 276
 277         lockdep_assert_held(&mvm->mutex);
 278         BUG_ON(mvm->scan_cmd == NULL);
 279
 280         IWL_DEBUG_SCAN(mvm, "Handling mac80211 scan request\n");
 281         mvm->scan_status = IWL_MVM_SCAN_OS;
 282         memset(cmd, 0, sizeof(struct iwl_scan_cmd) +
 283                mvm->fw->ucode_capa.max_probe_length +
 284                (MAX_NUM_SCAN_CHANNELS * sizeof(struct iwl_scan_channel)));
 285
 286         cmd->channel_count = (u8)req->n_channels;
 287         cmd->quiet_time = cpu_to_le16(IWL_ACTIVE_QUIET_TIME);
 288         cmd->quiet_plcp_th = cpu_to_le16(IWL_PLCP_QUIET_THRESH);
 289         cmd->rxchain_sel_flags = iwl_mvm_scan_rx_chain(mvm);
 290         cmd->max_out_time = iwl_mvm_scan_max_out_time(vif);
 291         cmd->suspend_time = iwl_mvm_scan_suspend_time(vif);
 292         cmd->rxon_flags = iwl_mvm_scan_rxon_flags(req);
 293         cmd->filter_flags = cpu_to_le32(MAC_FILTER_ACCEPT_GRP |
 294                                         MAC_FILTER_IN_BEACON);
 295
 296         if (vif->type == NL80211_IFTYPE_P2P_DEVICE)
 297                 cmd->type = cpu_to_le32(SCAN_TYPE_DISCOVERY_FORCED);
 298         else
 299                 cmd->type = cpu_to_le32(SCAN_TYPE_FORCED);
 300
 301         cmd->repeats = cpu_to_le32(1);
 302
 303         /*
 304          * If the user asked for passive scan, don't change to active scan if
 305          * you see any activity on the channel - remain passive.
 306          */
 307         if (req->n_ssids > 0) {
 308                 cmd->passive2active = cpu_to_le16(1);
 309                 ssid = req->ssids[0].ssid;
 310                 ssid_len = req->ssids[0].ssid_len;
 311         } else {
 312                 cmd->passive2active = 0;
 313         }
 314
 315         iwl_mvm_scan_fill_ssids(cmd, req);
 316
 317         cmd->tx_cmd.tx_flags = cpu_to_le32(TX_CMD_FLG_SEQ_CTL);
 318         cmd->tx_cmd.sta_id = mvm->aux_sta.sta_id;
 319         cmd->tx_cmd.life_time = cpu_to_le32(TX_CMD_LIFE_TIME_INFINITE);
 320         cmd->tx_cmd.rate_n_flags =
 321                         iwl_mvm_scan_rate_n_flags(mvm, req->channels[0]->band,
 322                                                   req->no_cck);
 323
 324         cmd->tx_cmd.len =
 325                 cpu_to_le16(iwl_mvm_fill_probe_req(
 326                             (struct ieee80211_mgmt *)cmd->data,
 327                             vif->addr,
 328                             req->n_ssids, ssid, ssid_len,
 329                             req->ie, req->ie_len,
 330                             mvm->fw->ucode_capa.max_probe_length));
 331
 332         iwl_mvm_scan_fill_channels(cmd, req);
 333
 334         cmd->len = cpu_to_le16(sizeof(struct iwl_scan_cmd) +
 335                 le16_to_cpu(cmd->tx_cmd.len) +
 336                 (cmd->channel_count * sizeof(struct iwl_scan_channel)));
 337         hcmd.len[0] = le16_to_cpu(cmd->len);
 338
 339         status = SCAN_RESPONSE_OK;
 340         ret = iwl_mvm_send_cmd_status(mvm, &hcmd, &status);
 341         if (!ret && status == SCAN_RESPONSE_OK) {
 342                 IWL_DEBUG_SCAN(mvm, "Scan request was sent successfully\n");
 343         } else {
 344                 /*
 345                  * If the scan failed, it usually means that the FW was unable
 346                  * to allocate the time events. Warn on it, but maybe we
 347                  * should try to send the command again with different params.
 348                  */
 349                 IWL_ERR(mvm, "Scan failed! status 0x%x ret %d\n",
 350                         status, ret);
 351                 mvm->scan_status = IWL_MVM_SCAN_NONE;
 352                 ret = -EIO;
 353         }
 354         return ret;
 355 }
 356
 357 int iwl_mvm_rx_scan_response(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb,
 358                           struct iwl_device_cmd *cmd)
 359 {
 360         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 361         struct iwl_cmd_response *resp = (void *)pkt->data;
 362
 363         IWL_DEBUG_SCAN(mvm, "Scan response received. status 0x%x\n",
 364                        le32_to_cpu(resp->status));
 365         return 0;
 366 }
 367
 368 int iwl_mvm_rx_scan_complete(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb,
 369                           struct iwl_device_cmd *cmd)
 370 {
 371         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 372         struct iwl_scan_complete_notif *notif = (void *)pkt->data;
 373
 374         IWL_DEBUG_SCAN(mvm, "Scan complete: status=0x%x scanned channels=%d\n",
 375                        notif->status, notif->scanned_channels);
 376
 377         mvm->scan_status = IWL_MVM_SCAN_NONE;
 378         ieee80211_scan_completed(mvm->hw, notif->status != SCAN_COMP_STATUS_OK);
 379
 380         return 0;
 381 }
 382
 383 static bool iwl_mvm_scan_abort_notif(struct iwl_notif_wait_data *notif_wait,
 384                                      struct iwl_rx_packet *pkt, void *data)
 385 {
 386         struct iwl_mvm *mvm =
 387                 container_of(notif_wait, struct iwl_mvm, notif_wait);
 388         struct iwl_scan_complete_notif *notif;
 389         u32 *resp;
 390
 391         switch (pkt->hdr.cmd) {
 392         case SCAN_ABORT_CMD:
 393                 resp = (void *)pkt->data;
 394                 if (*resp == CAN_ABORT_STATUS) {
 395                         IWL_DEBUG_SCAN(mvm,
 396                                        "Scan can be aborted, wait until completion\n");
 397                         return false;
 398                 }
 399
 400                 IWL_DEBUG_SCAN(mvm, "Scan cannot be aborted, exit now: %d\n",
 401                                *resp);
 402                 return true;
 403
 404         case SCAN_COMPLETE_NOTIFICATION:
 405                 notif = (void *)pkt->data;
 406                 IWL_DEBUG_SCAN(mvm, "Scan aborted: status 0x%x\n",
 407                                notif->status);
 408                 return true;
 409
 410         default:
 411                 WARN_ON(1);
 412                 return false;
 413         };
 414 }
 415
 416 void iwl_mvm_cancel_scan(struct iwl_mvm *mvm)
 417 {
 418         struct iwl_notification_wait wait_scan_abort;
 419         static const u8 scan_abort_notif[] = { SCAN_ABORT_CMD,
 420                                                SCAN_COMPLETE_NOTIFICATION };
 421         int ret;
 422
 423         iwl_init_notification_wait(&mvm->notif_wait, &wait_scan_abort,
 424                                    scan_abort_notif,
 425                                    ARRAY_SIZE(scan_abort_notif),
 426                                    iwl_mvm_scan_abort_notif, NULL);
 427
 428         ret = iwl_mvm_send_cmd_pdu(mvm, SCAN_ABORT_CMD, CMD_SYNC, 0, NULL);
 429         if (ret) {
 430                 IWL_ERR(mvm, "Couldn't send SCAN_ABORT_CMD: %d\n", ret);
 431                 goto out_remove_notif;
 432         }
 433
 434         ret = iwl_wait_notification(&mvm->notif_wait, &wait_scan_abort, 1 * HZ);
 435         if (ret)
 436                 IWL_ERR(mvm, "%s - failed on timeout\n", __func__);
 437
 438         return;
 439
 440 out_remove_notif:
 441         iwl_remove_notification(&mvm->notif_wait, &wait_scan_abort);
 442 }