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1/*2 * Copyright (c) 2012 Neratec Solutions AG3 *4 * Permission to use, copy, modify, and/or distribute this software for any5 * purpose with or without fee is hereby granted, provided that the above6 * copyright notice and this permission notice appear in all copies.7 *8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.15 */16 17#include <linux/slab.h>18#include <linux/export.h>19 20#include "dfs_pattern_detector.h"21#include "dfs_pri_detector.h"22#include "ath.h"23 24/**25 * struct radar_types - contains array of patterns defined for one DFS domain26 * @region: regulatory DFS region27 * @num_radar_types: number of radar types to follow28 * @radar_types: radar types array29 */30struct radar_types {31 enum nl80211_dfs_regions region;32 u32 num_radar_types;33 const struct radar_detector_specs *radar_types;34};35 36/* percentage on ppb threshold to trigger detection */37#define MIN_PPB_THRESH 5038#define PPB_THRESH_RATE(PPB, RATE) ((PPB * RATE + 100 - RATE) / 100)39#define PPB_THRESH(PPB) PPB_THRESH_RATE(PPB, MIN_PPB_THRESH)40#define PRF2PRI(PRF) ((1000000 + PRF / 2) / PRF)41/* percentage of pulse width tolerance */42#define WIDTH_TOLERANCE 543#define WIDTH_LOWER(X) ((X*(100-WIDTH_TOLERANCE)+50)/100)44#define WIDTH_UPPER(X) ((X*(100+WIDTH_TOLERANCE)+50)/100)45 46#define ETSI_PATTERN(ID, WMIN, WMAX, PMIN, PMAX, PRF, PPB, CHIRP) \47{ \48 ID, WIDTH_LOWER(WMIN), WIDTH_UPPER(WMAX), \49 (PRF2PRI(PMAX) - PRI_TOLERANCE), \50 (PRF2PRI(PMIN) * PRF + PRI_TOLERANCE), PRF, PPB * PRF, \51 PPB_THRESH(PPB), PRI_TOLERANCE, CHIRP \52}53 54/* radar types as defined by ETSI EN-301-893 v1.5.1 */55static const struct radar_detector_specs etsi_radar_ref_types_v15[] = {56 ETSI_PATTERN(0, 0, 1, 700, 700, 1, 18, false),57 ETSI_PATTERN(1, 0, 5, 200, 1000, 1, 10, false),58 ETSI_PATTERN(2, 0, 15, 200, 1600, 1, 15, false),59 ETSI_PATTERN(3, 0, 15, 2300, 4000, 1, 25, false),60 ETSI_PATTERN(4, 20, 30, 2000, 4000, 1, 20, false),61 ETSI_PATTERN(5, 0, 2, 300, 400, 3, 10, false),62 ETSI_PATTERN(6, 0, 2, 400, 1200, 3, 15, false),63};64 65static const struct radar_types etsi_radar_types_v15 = {66 .region = NL80211_DFS_ETSI,67 .num_radar_types = ARRAY_SIZE(etsi_radar_ref_types_v15),68 .radar_types = etsi_radar_ref_types_v15,69};70 71#define FCC_PATTERN(ID, WMIN, WMAX, PMIN, PMAX, PRF, PPB, CHIRP) \72{ \73 ID, WIDTH_LOWER(WMIN), WIDTH_UPPER(WMAX), \74 PMIN - PRI_TOLERANCE, \75 PMAX * PRF + PRI_TOLERANCE, PRF, PPB * PRF, \76 PPB_THRESH(PPB), PRI_TOLERANCE, CHIRP \77}78 79/* radar types released on August 14, 201480 * type 1 PRI values randomly selected within the range of 518 and 3066.81 * divide it to 3 groups is good enough for both of radar detection and82 * avoiding false detection based on practical test results83 * collected for more than a year.84 */85static const struct radar_detector_specs fcc_radar_ref_types[] = {86 FCC_PATTERN(0, 0, 1, 1428, 1428, 1, 18, false),87 FCC_PATTERN(101, 0, 1, 518, 938, 1, 57, false),88 FCC_PATTERN(102, 0, 1, 938, 2000, 1, 27, false),89 FCC_PATTERN(103, 0, 1, 2000, 3066, 1, 18, false),90 FCC_PATTERN(2, 0, 5, 150, 230, 1, 23, false),91 FCC_PATTERN(3, 6, 10, 200, 500, 1, 16, false),92 FCC_PATTERN(4, 11, 20, 200, 500, 1, 12, false),93 FCC_PATTERN(5, 50, 100, 1000, 2000, 1, 1, true),94 FCC_PATTERN(6, 0, 1, 333, 333, 1, 9, false),95};96 97static const struct radar_types fcc_radar_types = {98 .region = NL80211_DFS_FCC,99 .num_radar_types = ARRAY_SIZE(fcc_radar_ref_types),100 .radar_types = fcc_radar_ref_types,101};102 103#define JP_PATTERN(ID, WMIN, WMAX, PMIN, PMAX, PRF, PPB, RATE, CHIRP) \104{ \105 ID, WIDTH_LOWER(WMIN), WIDTH_UPPER(WMAX), \106 PMIN - PRI_TOLERANCE, \107 PMAX * PRF + PRI_TOLERANCE, PRF, PPB * PRF, \108 PPB_THRESH_RATE(PPB, RATE), PRI_TOLERANCE, CHIRP \109}110static const struct radar_detector_specs jp_radar_ref_types[] = {111 JP_PATTERN(0, 0, 1, 1428, 1428, 1, 18, 29, false),112 JP_PATTERN(1, 2, 3, 3846, 3846, 1, 18, 29, false),113 JP_PATTERN(2, 0, 1, 1388, 1388, 1, 18, 50, false),114 JP_PATTERN(3, 0, 4, 4000, 4000, 1, 18, 50, false),115 JP_PATTERN(4, 0, 5, 150, 230, 1, 23, 50, false),116 JP_PATTERN(5, 6, 10, 200, 500, 1, 16, 50, false),117 JP_PATTERN(6, 11, 20, 200, 500, 1, 12, 50, false),118 JP_PATTERN(7, 50, 100, 1000, 2000, 1, 3, 50, true),119 JP_PATTERN(5, 0, 1, 333, 333, 1, 9, 50, false),120};121 122static const struct radar_types jp_radar_types = {123 .region = NL80211_DFS_JP,124 .num_radar_types = ARRAY_SIZE(jp_radar_ref_types),125 .radar_types = jp_radar_ref_types,126};127 128static const struct radar_types *dfs_domains[] = {129 &etsi_radar_types_v15,130 &fcc_radar_types,131 &jp_radar_types,132};133 134/**135 * get_dfs_domain_radar_types() - get radar types for a given DFS domain136 * @region: regulatory DFS region137 *138 * Return value: radar_types ptr on success, NULL if DFS domain is not supported139 */140static const struct radar_types *141get_dfs_domain_radar_types(enum nl80211_dfs_regions region)142{143 u32 i;144 for (i = 0; i < ARRAY_SIZE(dfs_domains); i++) {145 if (dfs_domains[i]->region == region)146 return dfs_domains[i];147 }148 return NULL;149}150 151/**152 * struct channel_detector - detector elements for a DFS channel153 * @head: list_head154 * @freq: frequency for this channel detector in MHz155 * @detectors: array of dynamically created detector elements for this freq156 *157 * Channel detectors are required to provide multi-channel DFS detection, e.g.158 * to support off-channel scanning. A pattern detector has a list of channels159 * radar pulses have been reported for in the past.160 */161struct channel_detector {162 struct list_head head;163 u16 freq;164 struct pri_detector *detectors[];165};166 167/* channel_detector_reset() - reset detector lines for a given channel */168static void channel_detector_reset(struct dfs_pattern_detector *dpd,169 struct channel_detector *cd)170{171 u32 i;172 if (cd == NULL)173 return;174 for (i = 0; i < dpd->num_radar_types; i++)175 cd->detectors[i]->reset(cd->detectors[i], dpd->last_pulse_ts);176}177 178/* channel_detector_exit() - destructor */179static void channel_detector_exit(struct dfs_pattern_detector *dpd,180 struct channel_detector *cd)181{182 u32 i;183 if (cd == NULL)184 return;185 list_del(&cd->head);186 187 for (i = 0; i < dpd->num_radar_types; i++) {188 struct pri_detector *de = cd->detectors[i];189 if (de != NULL)190 de->exit(de);191 }192 193 kfree(cd);194}195 196static struct channel_detector *197channel_detector_create(struct dfs_pattern_detector *dpd, u16 freq)198{199 u32 i;200 struct channel_detector *cd;201 202 cd = kzalloc(struct_size(cd, detectors, dpd->num_radar_types), GFP_ATOMIC);203 if (cd == NULL)204 goto fail;205 206 INIT_LIST_HEAD(&cd->head);207 cd->freq = freq;208 209 for (i = 0; i < dpd->num_radar_types; i++) {210 const struct radar_detector_specs *rs = &dpd->radar_spec[i];211 struct pri_detector *de = pri_detector_init(rs);212 if (de == NULL)213 goto fail;214 cd->detectors[i] = de;215 }216 list_add(&cd->head, &dpd->channel_detectors);217 return cd;218 219fail:220 ath_dbg(dpd->common, DFS,221 "failed to allocate channel_detector for freq=%d\n", freq);222 channel_detector_exit(dpd, cd);223 return NULL;224}225 226/**227 * channel_detector_get() - get channel detector for given frequency228 * @dpd: DPD instance pointer229 * @freq: freq frequency in MHz230 *231 * Return value: pointer to channel detector on success, NULL otherwise232 *233 * Return existing channel detector for the given frequency or return a234 * newly create one.235 */236static struct channel_detector *237channel_detector_get(struct dfs_pattern_detector *dpd, u16 freq)238{239 struct channel_detector *cd;240 list_for_each_entry(cd, &dpd->channel_detectors, head) {241 if (cd->freq == freq)242 return cd;243 }244 return channel_detector_create(dpd, freq);245}246 247/*248 * DFS Pattern Detector249 */250 251/* dpd_reset(): reset all channel detectors */252static void dpd_reset(struct dfs_pattern_detector *dpd)253{254 struct channel_detector *cd;255 list_for_each_entry(cd, &dpd->channel_detectors, head)256 channel_detector_reset(dpd, cd);257 258}259static void dpd_exit(struct dfs_pattern_detector *dpd)260{261 struct channel_detector *cd, *cd0;262 list_for_each_entry_safe(cd, cd0, &dpd->channel_detectors, head)263 channel_detector_exit(dpd, cd);264 kfree(dpd);265}266 267static bool268dpd_add_pulse(struct dfs_pattern_detector *dpd, struct pulse_event *event,269 struct radar_detector_specs *rs)270{271 u32 i;272 struct channel_detector *cd;273 274 /*275 * pulses received for a non-supported or un-initialized276 * domain are treated as detected radars for fail-safety277 */278 if (dpd->region == NL80211_DFS_UNSET)279 return true;280 281 cd = channel_detector_get(dpd, event->freq);282 if (cd == NULL)283 return false;284 285 /* reset detector on time stamp wraparound, caused by TSF reset */286 if (event->ts < dpd->last_pulse_ts)287 dpd_reset(dpd);288 dpd->last_pulse_ts = event->ts;289 290 /* do type individual pattern matching */291 for (i = 0; i < dpd->num_radar_types; i++) {292 struct pri_detector *pd = cd->detectors[i];293 struct pri_sequence *ps = pd->add_pulse(pd, event);294 if (ps != NULL) {295 if (rs != NULL)296 memcpy(rs, pd->rs, sizeof(*rs));297 ath_dbg(dpd->common, DFS,298 "DFS: radar found on freq=%d: id=%d, pri=%d, "299 "count=%d, count_false=%d\n",300 event->freq, pd->rs->type_id,301 ps->pri, ps->count, ps->count_falses);302 pd->reset(pd, dpd->last_pulse_ts);303 return true;304 }305 }306 return false;307}308 309static struct ath_dfs_pool_stats310dpd_get_stats(struct dfs_pattern_detector *dpd)311{312 return global_dfs_pool_stats;313}314 315static bool dpd_set_domain(struct dfs_pattern_detector *dpd,316 enum nl80211_dfs_regions region)317{318 const struct radar_types *rt;319 struct channel_detector *cd, *cd0;320 321 if (dpd->region == region)322 return true;323 324 dpd->region = NL80211_DFS_UNSET;325 326 rt = get_dfs_domain_radar_types(region);327 if (rt == NULL)328 return false;329 330 /* delete all channel detectors for previous DFS domain */331 list_for_each_entry_safe(cd, cd0, &dpd->channel_detectors, head)332 channel_detector_exit(dpd, cd);333 dpd->radar_spec = rt->radar_types;334 dpd->num_radar_types = rt->num_radar_types;335 336 dpd->region = region;337 return true;338}339 340static const struct dfs_pattern_detector default_dpd = {341 .exit = dpd_exit,342 .set_dfs_domain = dpd_set_domain,343 .add_pulse = dpd_add_pulse,344 .get_stats = dpd_get_stats,345 .region = NL80211_DFS_UNSET,346};347 348struct dfs_pattern_detector *349dfs_pattern_detector_init(struct ath_common *common,350 enum nl80211_dfs_regions region)351{352 struct dfs_pattern_detector *dpd;353 354 if (!IS_ENABLED(CONFIG_CFG80211_CERTIFICATION_ONUS))355 return NULL;356 357 dpd = kmalloc(sizeof(*dpd), GFP_KERNEL);358 if (dpd == NULL)359 return NULL;360 361 *dpd = default_dpd;362 INIT_LIST_HEAD(&dpd->channel_detectors);363 364 dpd->common = common;365 if (dpd->set_dfs_domain(dpd, region))366 return dpd;367 368 ath_dbg(common, DFS,"Could not set DFS domain to %d", region);369 kfree(dpd);370 return NULL;371}372EXPORT_SYMBOL(dfs_pattern_detector_init);373