iwlwifi: improve scan support

This modifies iwlwifi to
 * no longer build its own probe request, but use mac80211's
 * therefore, support arbitrary scan IEs (up to the max len)
 * support multiple scan SSIDs
 * support passive scanning

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

6 files changed, 73 insertions, 177 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-commands.h b/drivers/net/wireless/iwlwifi/iwl-commands.h
index 411a5d2d9148..7b84d5246b36 100644
--- a/drivers/net/wireless/iwlwifi/iwl-commands.h
+++ b/drivers/net/wireless/iwlwifi/iwl-commands.h
@@ -2474,6 +2474,7 @@ struct iwl_ssid_ie {
 #define TX_CMD_LIFE_TIME_INFINITE       cpu_to_le32(0xFFFFFFFF)
 #define IWL_GOOD_CRC_TH                 cpu_to_le16(1)
 #define IWL_MAX_SCAN_SIZE 1024
+#define IWL_MAX_PROBE_REQUEST           200
 
 /*
  * REPLY_SCAN_CMD = 0x80 (command)
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c
index f23175240289..c43c57d7a4cb 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.c
+++ b/drivers/net/wireless/iwlwifi/iwl-core.c
@@ -1309,8 +1309,10 @@ int iwl_setup_mac(struct iwl_priv *priv)
                 BIT(NL80211_IFTYPE_ADHOC);
 
         hw->wiphy->custom_regulatory = true;
-        hw->wiphy->max_scan_ssids = 1;
-        hw->wiphy->max_scan_ie_len = 0; /* XXX for now */
+
+        hw->wiphy->max_scan_ssids = PROBE_OPTION_MAX;
+        /* we create the 802.11 header and a zero-length SSID element */
+        hw->wiphy->max_scan_ie_len = IWL_MAX_PROBE_REQUEST - 24 - 2;
 
         /* Default value; 4 EDCA QOS priorities */
         hw->queues = 4;
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.h b/drivers/net/wireless/iwlwifi/iwl-core.h
index 8773d733a54e..8ab60df48d56 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.h
+++ b/drivers/net/wireless/iwlwifi/iwl-core.h
@@ -396,8 +396,8 @@ int iwl_scan_cancel(struct iwl_priv *priv);
 int iwl_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms);
 int iwl_scan_initiate(struct iwl_priv *priv);
 int iwl_mac_hw_scan(struct ieee80211_hw *hw, struct cfg80211_scan_request *req);
-u16 iwl_fill_probe_req(struct iwl_priv *priv, enum ieee80211_band band,
-                       struct ieee80211_mgmt *frame, int left);
+u16 iwl_fill_probe_req(struct iwl_priv *priv, struct ieee80211_mgmt *frame,
+                       const u8 *ie, int ie_len, int left);
 void iwl_setup_rx_scan_handlers(struct iwl_priv *priv);
 u16 iwl_get_active_dwell_time(struct iwl_priv *priv,
                               enum ieee80211_band band,
diff --git a/drivers/net/wireless/iwlwifi/iwl-dev.h b/drivers/net/wireless/iwlwifi/iwl-dev.h
index 0922e33a7d42..e363d9b05eeb 100644
--- a/drivers/net/wireless/iwlwifi/iwl-dev.h
+++ b/drivers/net/wireless/iwlwifi/iwl-dev.h
@@ -889,9 +889,7 @@ struct iwl_priv {
         unsigned long scan_start_tsf;
         void *scan;
         int scan_bands;
-        int one_direct_scan;
-        u8 direct_ssid_len;
-        u8 direct_ssid[IW_ESSID_MAX_SIZE];
+        struct cfg80211_scan_request *scan_request;
         u8 scan_tx_ant[IEEE80211_NUM_BANDS];
         u8 mgmt_tx_ant;
 
diff --git a/drivers/net/wireless/iwlwifi/iwl-scan.c b/drivers/net/wireless/iwlwifi/iwl-scan.c
index 23644cf884f1..9edcf8c76b20 100644
--- a/drivers/net/wireless/iwlwifi/iwl-scan.c
+++ b/drivers/net/wireless/iwlwifi/iwl-scan.c
@@ -448,13 +448,6 @@ int iwl_mac_hw_scan(struct ieee80211_hw *hw,
         unsigned long flags;
         struct iwl_priv *priv = hw->priv;
         int ret;
-        u8 *ssid = NULL;
-        size_t ssid_len = 0;
-
-        if (req->n_ssids) {
-                ssid = req->ssids[0].ssid;
-                ssid_len = req->ssids[0].ssid_len;
-        }
 
         IWL_DEBUG_MAC80211(priv, "enter\n");
 
@@ -488,13 +481,7 @@ int iwl_mac_hw_scan(struct ieee80211_hw *hw,
                 goto out_unlock;
         }
 
-        if (ssid_len) {
-                priv->one_direct_scan = 1;
-                priv->direct_ssid_len =  ssid_len;
-                memcpy(priv->direct_ssid, ssid, priv->direct_ssid_len);
-        } else {
-                priv->one_direct_scan = 0;
-        }
+        priv->scan_request = req;
 
         ret = iwl_scan_initiate(priv);
 
@@ -533,73 +520,14 @@ void iwl_bg_scan_check(struct work_struct *data)
 EXPORT_SYMBOL(iwl_bg_scan_check);
 
 /**
- * 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_cap.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_cap.cap);
-        memcpy(&ht_cap->mcs, &sband->ht_cap.mcs, 16);
-        ht_cap->ampdu_params_info =
-                (sband->ht_cap.ampdu_factor & IEEE80211_HT_AMPDU_PARM_FACTOR) |
-                ((sband->ht_cap.ampdu_density << 2) &
-                        IEEE80211_HT_AMPDU_PARM_DENSITY);
-        *left -= sizeof(struct ieee80211_ht_cap);
-}
-
-/**
  * iwl_fill_probe_req - fill in all required fields and IE for probe request
  */
 
-u16 iwl_fill_probe_req(struct iwl_priv *priv,
-                       enum ieee80211_band band,
-                       struct ieee80211_mgmt *frame,
-                       int left)
+u16 iwl_fill_probe_req(struct iwl_priv *priv, struct ieee80211_mgmt *frame,
+                       const u8 *ies, int ie_len, 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 */
@@ -627,62 +555,12 @@ u16 iwl_fill_probe_req(struct iwl_priv *priv,
 
         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;
+        if (WARN_ON(left < ie_len))
+                return len;
 
-        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;
+        memcpy(pos, ies, ie_len);
+        len += ie_len;
+        left -= ie_len;
 
         return (u16)len;
 }
@@ -703,10 +581,10 @@ static void iwl_bg_request_scan(struct work_struct *data)
         u32 rate_flags = 0;
         u16 cmd_len;
         enum ieee80211_band band;
-        u8 n_probes = 2;
+        u8 n_probes = 0;
         u8 rx_chain = priv->hw_params.valid_rx_ant;
         u8 rate;
-        DECLARE_SSID_BUF(ssid);
+        bool is_active = false;
 
         conf = ieee80211_get_hw_conf(priv->hw);
 
@@ -796,19 +674,25 @@ static void iwl_bg_request_scan(struct work_struct *data)
                                scan_suspend_time, interval);
         }
 
-        /* We should add the ability for user to lock to PASSIVE ONLY */
-        if (priv->one_direct_scan) {
-                IWL_DEBUG_SCAN(priv, "Start direct scan for '%s'\n",
-                                print_ssid(ssid, 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 {
-                IWL_DEBUG_SCAN(priv, "Start indirect scan.\n");
-        }
+        if (priv->scan_request->n_ssids) {
+                int i, p = 0;
+                IWL_DEBUG_SCAN(priv, "Kicking off active scan\n");
+                for (i = 0; i < priv->scan_request->n_ssids; i++) {
+                        /* always does wildcard anyway */
+                        if (!priv->scan_request->ssids[i].ssid_len)
+                                continue;
+                        scan->direct_scan[p].id = WLAN_EID_SSID;
+                        scan->direct_scan[p].len =
+                                priv->scan_request->ssids[i].ssid_len;
+                        memcpy(scan->direct_scan[p].ssid,
+                               priv->scan_request->ssids[i].ssid,
+                               priv->scan_request->ssids[i].ssid_len);
+                        n_probes++;
+                        p++;
+                }
+                is_active = true;
+        } else
+                IWL_DEBUG_SCAN(priv, "Start passive scan.\n");
 
         scan->tx_cmd.tx_flags = TX_CMD_FLG_SEQ_CTL_MSK;
         scan->tx_cmd.sta_id = priv->hw_params.bcast_sta_id;
@@ -850,10 +734,11 @@ static void iwl_bg_request_scan(struct work_struct *data)
                                 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));
+        cmd_len = iwl_fill_probe_req(priv,
+                                (struct ieee80211_mgmt *)scan->data,
+                                priv->scan_request->ie,
+                                priv->scan_request->ie_len,
+                                IWL_MAX_SCAN_SIZE - sizeof(*scan));
 
         scan->tx_cmd.len = cpu_to_le16(cmd_len);
 
@@ -864,8 +749,7 @@ static void iwl_bg_request_scan(struct work_struct *data)
                                RXON_FILTER_BCON_AWARE_MSK);
 
         scan->channel_count =
-                iwl_get_channels_for_scan(priv, band, 1, /* active */
-                        n_probes,
+                iwl_get_channels_for_scan(priv, band, is_active, n_probes,
                         (void *)&scan->data[le16_to_cpu(scan->tx_cmd.len)]);
 
         if (scan->channel_count == 0) {
@@ -928,6 +812,7 @@ void iwl_bg_scan_completed(struct work_struct *work)
         if (test_bit(STATUS_EXIT_PENDING, &priv->status))
                 return;
 
+        priv->scan_request = NULL;
         ieee80211_scan_completed(priv->hw, false);
 
         /* Since setting the TXPOWER may have been deferred while
diff --git a/drivers/net/wireless/iwlwifi/iwl3945-base.c b/drivers/net/wireless/iwlwifi/iwl3945-base.c
index ed497551a860..4df9b4b5072a 100644
--- a/drivers/net/wireless/iwlwifi/iwl3945-base.c
+++ b/drivers/net/wireless/iwlwifi/iwl3945-base.c
@@ -2942,9 +2942,9 @@ static void iwl3945_bg_request_scan(struct work_struct *data)
         int rc = 0;
         struct iwl3945_scan_cmd *scan;
         struct ieee80211_conf *conf = NULL;
-        u8 n_probes = 2;
+        u8 n_probes = 0;
         enum ieee80211_band band;
-        DECLARE_SSID_BUF(ssid);
+        bool is_active = false;
 
         conf = ieee80211_get_hw_conf(priv->hw);
 
@@ -3043,18 +3043,25 @@ static void iwl3945_bg_request_scan(struct work_struct *data)
                                scan_suspend_time, interval);
         }
 
-        /* We should add the ability for user to lock to PASSIVE ONLY */
-        if (priv->one_direct_scan) {
-                IWL_DEBUG_SCAN(priv, "Kicking off one direct scan for '%s'\n",
-                                print_ssid(ssid, 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++;
+        if (priv->scan_request->n_ssids) {
+                int i, p = 0;
+                IWL_DEBUG_SCAN(priv, "Kicking off active scan\n");
+                for (i = 0; i < priv->scan_request->n_ssids; i++) {
+                        /* always does wildcard anyway */
+                        if (!priv->scan_request->ssids[i].ssid_len)
+                                continue;
+                        scan->direct_scan[p].id = WLAN_EID_SSID;
+                        scan->direct_scan[p].len =
+                                priv->scan_request->ssids[i].ssid_len;
+                        memcpy(scan->direct_scan[p].ssid,
+                               priv->scan_request->ssids[i].ssid,
+                               priv->scan_request->ssids[i].ssid_len);
+                        n_probes++;
+                        p++;
+                }
+                is_active = true;
         } else
-                IWL_DEBUG_SCAN(priv, "Kicking off one indirect scan.\n");
+                IWL_DEBUG_SCAN(priv, "Kicking off passive scan.\n");
 
         /* We don't build a direct scan probe request; the uCode will do
          * that based on the direct_mask added to each channel entry */
@@ -3079,9 +3086,11 @@ static void iwl3945_bg_request_scan(struct work_struct *data)
         }
 
         scan->tx_cmd.len = cpu_to_le16(
-                iwl_fill_probe_req(priv, band,
-                                   (struct ieee80211_mgmt *)scan->data,
-                                   IWL_MAX_SCAN_SIZE - sizeof(*scan)));
+                        iwl_fill_probe_req(priv,
+                                (struct ieee80211_mgmt *)scan->data,
+                                priv->scan_request->ie,
+                                priv->scan_request->ie_len,
+                                IWL_MAX_SCAN_SIZE - sizeof(*scan)));
 
         /* select Rx antennas */
         scan->flags |= iwl3945_get_antenna_flags(priv);
@@ -3090,8 +3099,7 @@ static void iwl3945_bg_request_scan(struct work_struct *data)
                 scan->filter_flags = RXON_FILTER_PROMISC_MSK;
 
         scan->channel_count =
-                iwl3945_get_channels_for_scan(priv, band, 1, /* active */
-                                              n_probes,
+                iwl3945_get_channels_for_scan(priv, band, is_active, n_probes,
                         (void *)&scan->data[le16_to_cpu(scan->tx_cmd.len)]);
 
         if (scan->channel_count == 0) {
@@ -4119,7 +4127,9 @@ static int iwl3945_setup_mac(struct iwl_priv *priv)
 
         hw->wiphy->custom_regulatory = true;
 
-        hw->wiphy->max_scan_ssids = 1; /* WILL FIX */
+        hw->wiphy->max_scan_ssids = PROBE_OPTION_MAX_3945;
+        /* we create the 802.11 header and a zero-length SSID element */
+        hw->wiphy->max_scan_ie_len = IWL_MAX_PROBE_REQUEST - 24 - 2;
 
         /* Default value; 4 EDCA QOS priorities */
         hw->queues = 4;