drivers/net/wireless/orinoco/scan.c

   1 /* Helpers for managing scan queues
   2  *
   3  * See copyright notice in main.c
   4  */
   5
   6 #include <linux/gfp.h>
   7 #include <linux/kernel.h>
   8 #include <linux/string.h>
   9 #include <linux/ieee80211.h>
  10 #include <net/cfg80211.h>
  11
  12 #include "hermes.h"
  13 #include "orinoco.h"
  14 #include "main.h"
  15
  16 #include "scan.h"
  17
  18 #define ZERO_DBM_OFFSET 0x95
  19 #define MAX_SIGNAL_LEVEL 0x8A
  20 #define MIN_SIGNAL_LEVEL 0x2F
  21
  22 #define SIGNAL_TO_DBM(x)                                        \
  23         (clamp_t(s32, (x), MIN_SIGNAL_LEVEL, MAX_SIGNAL_LEVEL)  \
  24          - ZERO_DBM_OFFSET)
  25 #define SIGNAL_TO_MBM(x) (SIGNAL_TO_DBM(x) * 100)
  26
  27 static int symbol_build_supp_rates(u8 *buf, const __le16 *rates)
  28 {
  29         int i;
  30         u8 rate;
  31
  32         buf[0] = WLAN_EID_SUPP_RATES;
  33         for (i = 0; i < 5; i++) {
  34                 rate = le16_to_cpu(rates[i]);
  35                 /* NULL terminated */
  36                 if (rate == 0x0)
  37                         break;
  38                 buf[i + 2] = rate;
  39         }
  40         buf[1] = i;
  41
  42         return i + 2;
  43 }
  44
  45 static int prism_build_supp_rates(u8 *buf, const u8 *rates)
  46 {
  47         int i;
  48
  49         buf[0] = WLAN_EID_SUPP_RATES;
  50         for (i = 0; i < 8; i++) {
  51                 /* NULL terminated */
  52                 if (rates[i] == 0x0)
  53                         break;
  54                 buf[i + 2] = rates[i];
  55         }
  56         buf[1] = i;
  57
  58         /* We might still have another 2 rates, which need to go in
  59          * extended supported rates */
  60         if (i == 8 && rates[i] > 0) {
  61                 buf[10] = WLAN_EID_EXT_SUPP_RATES;
  62                 for (; i < 10; i++) {
  63                         /* NULL terminated */
  64                         if (rates[i] == 0x0)
  65                                 break;
  66                         buf[i + 2] = rates[i];
  67                 }
  68                 buf[11] = i - 8;
  69         }
  70
  71         return (i < 8) ? i + 2 : i + 4;
  72 }
  73
  74 static void orinoco_add_hostscan_result(struct orinoco_private *priv,
  75                                         const union hermes_scan_info *bss)
  76 {
  77         struct wiphy *wiphy = priv_to_wiphy(priv);
  78         struct ieee80211_channel *channel;
  79         u8 *ie;
  80         u8 ie_buf[46];
  81         u64 timestamp;
  82         s32 signal;
  83         u16 capability;
  84         u16 beacon_interval;
  85         int ie_len;
  86         int freq;
  87         int len;
  88
  89         len = le16_to_cpu(bss->a.essid_len);
  90
  91         /* Reconstruct SSID and bitrate IEs to pass up */
  92         ie_buf[0] = WLAN_EID_SSID;
  93         ie_buf[1] = len;
  94         memcpy(&ie_buf[2], bss->a.essid, len);
  95
  96         ie = ie_buf + len + 2;
  97         ie_len = ie_buf[1] + 2;
  98         switch (priv->firmware_type) {
  99         case FIRMWARE_TYPE_SYMBOL:
 100                 ie_len += symbol_build_supp_rates(ie, bss->s.rates);
 101                 break;
 102
 103         case FIRMWARE_TYPE_INTERSIL:
 104                 ie_len += prism_build_supp_rates(ie, bss->p.rates);
 105                 break;
 106
 107         case FIRMWARE_TYPE_AGERE:
 108         default:
 109                 break;
 110         }
 111
 112         freq = ieee80211_dsss_chan_to_freq(le16_to_cpu(bss->a.channel));
 113         channel = ieee80211_get_channel(wiphy, freq);
 114         if (!channel) {
 115                 printk(KERN_DEBUG "Invalid channel designation %04X(%04X)",
 116                         bss->a.channel, freq);
 117                 return; /* Then ignore it for now */
 118         }
 119         timestamp = 0;
 120         capability = le16_to_cpu(bss->a.capabilities);
 121         beacon_interval = le16_to_cpu(bss->a.beacon_interv);
 122         signal = SIGNAL_TO_MBM(le16_to_cpu(bss->a.level));
 123
 124         cfg80211_inform_bss(wiphy, channel, bss->a.bssid, timestamp,
 125                             capability, beacon_interval, ie_buf, ie_len,
 126                             signal, GFP_KERNEL);
 127 }
 128
 129 void orinoco_add_extscan_result(struct orinoco_private *priv,
 130                                 struct agere_ext_scan_info *bss,
 131                                 size_t len)
 132 {
 133         struct wiphy *wiphy = priv_to_wiphy(priv);
 134         struct ieee80211_channel *channel;
 135         const u8 *ie;
 136         u64 timestamp;
 137         s32 signal;
 138         u16 capability;
 139         u16 beacon_interval;
 140         size_t ie_len;
 141         int chan, freq;
 142
 143         ie_len = len - sizeof(*bss);
 144         ie = cfg80211_find_ie(WLAN_EID_DS_PARAMS, bss->data, ie_len);
 145         chan = ie ? ie[2] : 0;
 146         freq = ieee80211_dsss_chan_to_freq(chan);
 147         channel = ieee80211_get_channel(wiphy, freq);
 148
 149         timestamp = le64_to_cpu(bss->timestamp);
 150         capability = le16_to_cpu(bss->capabilities);
 151         beacon_interval = le16_to_cpu(bss->beacon_interval);
 152         ie = bss->data;
 153         signal = SIGNAL_TO_MBM(bss->level);
 154
 155         cfg80211_inform_bss(wiphy, channel, bss->bssid, timestamp,
 156                             capability, beacon_interval, ie, ie_len,
 157                             signal, GFP_KERNEL);
 158 }
 159
 160 void orinoco_add_hostscan_results(struct orinoco_private *priv,
 161                                   unsigned char *buf,
 162                                   size_t len)
 163 {
 164         int offset;             /* In the scan data */
 165         size_t atom_len;
 166         bool abort = false;
 167
 168         switch (priv->firmware_type) {
 169         case FIRMWARE_TYPE_AGERE:
 170                 atom_len = sizeof(struct agere_scan_apinfo);
 171                 offset = 0;
 172                 break;
 173
 174         case FIRMWARE_TYPE_SYMBOL:
 175                 /* Lack of documentation necessitates this hack.
 176                  * Different firmwares have 68 or 76 byte long atoms.
 177                  * We try modulo first.  If the length divides by both,
 178                  * we check what would be the channel in the second
 179                  * frame for a 68-byte atom.  76-byte atoms have 0 there.
 180                  * Valid channel cannot be 0.  */
 181                 if (len % 76)
 182                         atom_len = 68;
 183                 else if (len % 68)
 184                         atom_len = 76;
 185                 else if (len >= 1292 && buf[68] == 0)
 186                         atom_len = 76;
 187                 else
 188                         atom_len = 68;
 189                 offset = 0;
 190                 break;
 191
 192         case FIRMWARE_TYPE_INTERSIL:
 193                 offset = 4;
 194                 if (priv->has_hostscan) {
 195                         atom_len = le16_to_cpup((__le16 *)buf);
 196                         /* Sanity check for atom_len */
 197                         if (atom_len < sizeof(struct prism2_scan_apinfo)) {
 198                                 printk(KERN_ERR "%s: Invalid atom_len in scan "
 199                                        "data: %zu\n", priv->ndev->name,
 200                                        atom_len);
 201                                 abort = true;
 202                                 goto scan_abort;
 203                         }
 204                 } else
 205                         atom_len = offsetof(struct prism2_scan_apinfo, atim);
 206                 break;
 207
 208         default:
 209                 abort = true;
 210                 goto scan_abort;
 211         }
 212
 213         /* Check that we got an whole number of atoms */
 214         if ((len - offset) % atom_len) {
 215                 printk(KERN_ERR "%s: Unexpected scan data length %zu, "
 216                        "atom_len %zu, offset %d\n", priv->ndev->name, len,
 217                        atom_len, offset);
 218                 abort = true;
 219                 goto scan_abort;
 220         }
 221
 222         /* Process the entries one by one */
 223         for (; offset + atom_len <= len; offset += atom_len) {
 224                 union hermes_scan_info *atom;
 225
 226                 atom = (union hermes_scan_info *) (buf + offset);
 227
 228                 orinoco_add_hostscan_result(priv, atom);
 229         }
 230
 231  scan_abort:
 232         if (priv->scan_request) {
 233                 cfg80211_scan_done(priv->scan_request, abort);
 234                 priv->scan_request = NULL;
 235         }
 236 }
 237
 238 void orinoco_scan_done(struct orinoco_private *priv, bool abort)
 239 {
 240         if (priv->scan_request) {
 241                 cfg80211_scan_done(priv->scan_request, abort);
 242                 priv->scan_request = NULL;
 243         }
 244 }