ath9k-$(CONFIG_ATH9K_AHB) += ahb.o
ath9k-$(CONFIG_ATH9K_DEBUGFS) += debug.o
ath9k-$(CONFIG_ATH9K_DFS_DEBUGFS) += dfs_debug.o
-ath9k-$(CONFIG_ATH9K_DFS_CERTIFIED) += dfs.o
+ath9k-$(CONFIG_ATH9K_DFS_CERTIFIED) += \
+ dfs.o \
+ dfs_pattern_detector.o \
+ dfs_pri_detector.o
obj-$(CONFIG_ATH9K) += ath9k.o
--- /dev/null
+/*
+ * Copyright (c) 2012 Neratec Solutions AG
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <linux/slab.h>
+#include <linux/export.h>
+
+#include "dfs_pattern_detector.h"
+#include "dfs_pri_detector.h"
+
+/*
+ * tolerated deviation of radar time stamp in usecs on both sides
+ * TODO: this might need to be HW-dependent
+ */
+#define PRI_TOLERANCE 16
+
+/**
+ * struct radar_types - contains array of patterns defined for one DFS domain
+ * @domain: DFS regulatory domain
+ * @num_radar_types: number of radar types to follow
+ * @radar_types: radar types array
+ */
+struct radar_types {
+ enum nl80211_dfs_regions region;
+ u32 num_radar_types;
+ const struct radar_detector_specs *radar_types;
+};
+
+/* percentage on ppb threshold to trigger detection */
+#define MIN_PPB_THRESH 50
+#define PPB_THRESH(PPB) ((PPB * MIN_PPB_THRESH + 50) / 100)
+#define PRF2PRI(PRF) ((1000000 + PRF / 2) / PRF)
+
+#define ETSI_PATTERN(ID, WMIN, WMAX, PMIN, PMAX, PRF, PPB) \
+{ \
+ ID, WMIN, WMAX, (PRF2PRI(PMAX) - PRI_TOLERANCE), \
+ (PRF2PRI(PMIN) * PRF + PRI_TOLERANCE), PRF, PPB * PRF, \
+ PPB_THRESH(PPB), PRI_TOLERANCE, \
+}
+
+/* radar types as defined by ETSI EN-301-893 v1.5.1 */
+static const struct radar_detector_specs etsi_radar_ref_types_v15[] = {
+ ETSI_PATTERN(0, 0, 1, 700, 700, 1, 18),
+ ETSI_PATTERN(1, 0, 5, 200, 1000, 1, 10),
+ ETSI_PATTERN(2, 0, 15, 200, 1600, 1, 15),
+ ETSI_PATTERN(3, 0, 15, 2300, 4000, 1, 25),
+ ETSI_PATTERN(4, 20, 30, 2000, 4000, 1, 20),
+ ETSI_PATTERN(5, 0, 2, 300, 400, 3, 10),
+ ETSI_PATTERN(6, 0, 2, 400, 1200, 3, 15),
+};
+
+static const struct radar_types etsi_radar_types_v15 = {
+ .region = NL80211_DFS_ETSI,
+ .num_radar_types = ARRAY_SIZE(etsi_radar_ref_types_v15),
+ .radar_types = etsi_radar_ref_types_v15,
+};
+
+/* for now, we support ETSI radar types, FCC and JP are TODO */
+static const struct radar_types *dfs_domains[] = {
+ &etsi_radar_types_v15,
+};
+
+/**
+ * get_dfs_domain_radar_types() - get radar types for a given DFS domain
+ * @param domain DFS domain
+ * @return radar_types ptr on success, NULL if DFS domain is not supported
+ */
+static const struct radar_types *
+get_dfs_domain_radar_types(enum nl80211_dfs_regions region)
+{
+ u32 i;
+ for (i = 0; i < ARRAY_SIZE(dfs_domains); i++) {
+ if (dfs_domains[i]->region == region)
+ return dfs_domains[i];
+ }
+ return NULL;
+}
+
+/**
+ * struct channel_detector - detector elements for a DFS channel
+ * @head: list_head
+ * @freq: frequency for this channel detector in MHz
+ * @detectors: array of dynamically created detector elements for this freq
+ *
+ * Channel detectors are required to provide multi-channel DFS detection, e.g.
+ * to support off-channel scanning. A pattern detector has a list of channels
+ * radar pulses have been reported for in the past.
+ */
+struct channel_detector {
+ struct list_head head;
+ u16 freq;
+ struct pri_detector **detectors;
+};
+
+/* channel_detector_reset() - reset detector lines for a given channel */
+static void channel_detector_reset(struct dfs_pattern_detector *dpd,
+ struct channel_detector *cd)
+{
+ u32 i;
+ if (cd == NULL)
+ return;
+ for (i = 0; i < dpd->num_radar_types; i++)
+ cd->detectors[i]->reset(cd->detectors[i], dpd->last_pulse_ts);
+}
+
+/* channel_detector_exit() - destructor */
+static void channel_detector_exit(struct dfs_pattern_detector *dpd,
+ struct channel_detector *cd)
+{
+ u32 i;
+ if (cd == NULL)
+ return;
+ list_del(&cd->head);
+ for (i = 0; i < dpd->num_radar_types; i++) {
+ struct pri_detector *de = cd->detectors[i];
+ if (de != NULL)
+ de->exit(de);
+ }
+ kfree(cd->detectors);
+ kfree(cd);
+}
+
+static struct channel_detector *
+channel_detector_create(struct dfs_pattern_detector *dpd, u16 freq)
+{
+ u32 sz, i;
+ struct channel_detector *cd;
+
+ cd = kmalloc(sizeof(*cd), GFP_KERNEL);
+ if (cd == NULL)
+ goto fail;
+
+ INIT_LIST_HEAD(&cd->head);
+ cd->freq = freq;
+ sz = sizeof(cd->detectors) * dpd->num_radar_types;
+ cd->detectors = kzalloc(sz, GFP_KERNEL);
+ if (cd->detectors == NULL)
+ goto fail;
+
+ for (i = 0; i < dpd->num_radar_types; i++) {
+ const struct radar_detector_specs *rs = &dpd->radar_spec[i];
+ struct pri_detector *de = pri_detector_init(rs);
+ if (de == NULL)
+ goto fail;
+ cd->detectors[i] = de;
+ }
+ list_add(&cd->head, &dpd->channel_detectors);
+ return cd;
+
+fail:
+ pr_err("failed to allocate channel_detector for freq=%d\n", freq);
+ channel_detector_exit(dpd, cd);
+ return NULL;
+}
+
+/**
+ * channel_detector_get() - get channel detector for given frequency
+ * @param dpd instance pointer
+ * @param freq frequency in MHz
+ * @return pointer to channel detector on success, NULL otherwise
+ *
+ * Return existing channel detector for the given frequency or return a
+ * newly create one.
+ */
+static struct channel_detector *
+channel_detector_get(struct dfs_pattern_detector *dpd, u16 freq)
+{
+ struct channel_detector *cd;
+ list_for_each_entry(cd, &dpd->channel_detectors, head) {
+ if (cd->freq == freq)
+ return cd;
+ }
+ return channel_detector_create(dpd, freq);
+}
+
+/*
+ * DFS Pattern Detector
+ */
+
+/* dpd_reset(): reset all channel detectors */
+static void dpd_reset(struct dfs_pattern_detector *dpd)
+{
+ struct channel_detector *cd;
+ if (!list_empty(&dpd->channel_detectors))
+ list_for_each_entry(cd, &dpd->channel_detectors, head)
+ channel_detector_reset(dpd, cd);
+
+}
+static void dpd_exit(struct dfs_pattern_detector *dpd)
+{
+ struct channel_detector *cd, *cd0;
+ if (!list_empty(&dpd->channel_detectors))
+ list_for_each_entry_safe(cd, cd0, &dpd->channel_detectors, head)
+ channel_detector_exit(dpd, cd);
+ kfree(dpd);
+}
+
+static bool
+dpd_add_pulse(struct dfs_pattern_detector *dpd, struct pulse_event *event)
+{
+ u32 i;
+ bool ts_wraparound;
+ struct channel_detector *cd;
+
+ if (dpd->region == NL80211_DFS_UNSET) {
+ /*
+ * pulses received for a non-supported or un-initialized
+ * domain are treated as detected radars
+ */
+ return true;
+ }
+
+ cd = channel_detector_get(dpd, event->freq);
+ if (cd == NULL)
+ return false;
+
+ ts_wraparound = (event->ts < dpd->last_pulse_ts);
+ dpd->last_pulse_ts = event->ts;
+ if (ts_wraparound) {
+ /*
+ * reset detector on time stamp wraparound
+ * with monotonic time stamps, this should never happen
+ */
+ pr_warn("DFS: time stamp wraparound detected, resetting\n");
+ dpd_reset(dpd);
+ }
+ /* do type individual pattern matching */
+ for (i = 0; i < dpd->num_radar_types; i++) {
+ if (cd->detectors[i]->add_pulse(cd->detectors[i], event) != 0) {
+ channel_detector_reset(dpd, cd);
+ return true;
+ }
+ }
+ return false;
+}
+
+static bool dpd_set_domain(struct dfs_pattern_detector *dpd,
+ enum nl80211_dfs_regions region)
+{
+ const struct radar_types *rt;
+ struct channel_detector *cd, *cd0;
+
+ if (dpd->region == region)
+ return true;
+
+ dpd->region = NL80211_DFS_UNSET;
+
+ rt = get_dfs_domain_radar_types(region);
+ if (rt == NULL)
+ return false;
+
+ /* delete all channel detectors for previous DFS domain */
+ if (!list_empty(&dpd->channel_detectors))
+ list_for_each_entry_safe(cd, cd0, &dpd->channel_detectors, head)
+ channel_detector_exit(dpd, cd);
+ dpd->radar_spec = rt->radar_types;
+ dpd->num_radar_types = rt->num_radar_types;
+
+ dpd->region = region;
+ return true;
+}
+
+static struct dfs_pattern_detector default_dpd = {
+ .exit = dpd_exit,
+ .set_domain = dpd_set_domain,
+ .add_pulse = dpd_add_pulse,
+ .region = NL80211_DFS_UNSET,
+};
+
+struct dfs_pattern_detector *
+dfs_pattern_detector_init(enum nl80211_dfs_regions region)
+{
+ struct dfs_pattern_detector *dpd;
+ dpd = kmalloc(sizeof(*dpd), GFP_KERNEL);
+ if (dpd == NULL) {
+ pr_err("allocation of dfs_pattern_detector failed\n");
+ return NULL;
+ }
+ *dpd = default_dpd;
+ INIT_LIST_HEAD(&dpd->channel_detectors);
+
+ if (dpd->set_domain(dpd, region))
+ return dpd;
+
+ pr_err("Could not set DFS domain to %d. ", region);
+ return NULL;
+}
+EXPORT_SYMBOL(dfs_pattern_detector_init);
--- /dev/null
+/*
+ * Copyright (c) 2012 Neratec Solutions AG
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef DFS_PATTERN_DETECTOR_H
+#define DFS_PATTERN_DETECTOR_H
+
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/nl80211.h>
+
+/**
+ * struct pulse_event - describing pulses reported by PHY
+ * @ts: pulse time stamp in us
+ * @freq: channel frequency in MHz
+ * @width: pulse duration in us
+ * @rssi: rssi of radar event
+ */
+struct pulse_event {
+ u64 ts;
+ u16 freq;
+ u8 width;
+ u8 rssi;
+};
+
+/**
+ * struct radar_detector_specs - detector specs for a radar pattern type
+ * @type_id: pattern type, as defined by regulatory
+ * @width_min: minimum radar pulse width in [us]
+ * @width_max: maximum radar pulse width in [us]
+ * @pri_min: minimum pulse repetition interval in [us] (including tolerance)
+ * @pri_max: minimum pri in [us] (including tolerance)
+ * @num_pri: maximum number of different pri for this type
+ * @ppb: pulses per bursts for this type
+ * @ppb_thresh: number of pulses required to trigger detection
+ * @max_pri_tolerance: pulse time stamp tolerance on both sides [us]
+ */
+struct radar_detector_specs {
+ u8 type_id;
+ u8 width_min;
+ u8 width_max;
+ u16 pri_min;
+ u16 pri_max;
+ u8 num_pri;
+ u8 ppb;
+ u8 ppb_thresh;
+ u8 max_pri_tolerance;
+};
+
+/**
+ * struct dfs_pattern_detector - DFS pattern detector
+ * @exit(): destructor
+ * @set_domain(): set DFS domain, resets detector lines upon domain changes
+ * @add_pulse(): add radar pulse to detector, returns true on detection
+ * @region: active DFS region, NL80211_DFS_UNSET until set
+ * @num_radar_types: number of different radar types
+ * @last_pulse_ts: time stamp of last valid pulse in usecs
+ * @radar_detector_specs: array of radar detection specs
+ * @channel_detectors: list connecting channel_detector elements
+ */
+struct dfs_pattern_detector {
+ void (*exit)(struct dfs_pattern_detector *dpd);
+ bool (*set_domain)(struct dfs_pattern_detector *dpd,
+ enum nl80211_dfs_regions region);
+ bool (*add_pulse)(struct dfs_pattern_detector *dpd,
+ struct pulse_event *pe);
+
+ enum nl80211_dfs_regions region;
+ u8 num_radar_types;
+ u64 last_pulse_ts;
+
+ const struct radar_detector_specs *radar_spec;
+ struct list_head channel_detectors;
+};
+
+/**
+ * dfs_pattern_detector_init() - constructor for pattern detector class
+ * @param region: DFS domain to be used, can be NL80211_DFS_UNSET at creation
+ * @return instance pointer on success, NULL otherwise
+ */
+#if defined(CONFIG_ATH9K_DFS_CERTIFIED)
+extern struct dfs_pattern_detector *
+dfs_pattern_detector_init(enum nl80211_dfs_regions region);
+#else
+static inline struct dfs_pattern_detector *
+dfs_pattern_detector_init(enum nl80211_dfs_regions region)
+{
+ return NULL;
+}
+#endif /* CONFIG_ATH9K_DFS_CERTIFIED */
+
+#endif /* DFS_PATTERN_DETECTOR_H */
--- /dev/null
+/*
+ * Copyright (c) 2012 Neratec Solutions AG
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <linux/slab.h>
+
+#include "dfs_pattern_detector.h"
+#include "dfs_pri_detector.h"
+
+/**
+ * struct pri_sequence - sequence of pulses matching one PRI
+ * @head: list_head
+ * @pri: pulse repetition interval (PRI) in usecs
+ * @dur: duration of sequence in usecs
+ * @count: number of pulses in this sequence
+ * @count_falses: number of not matching pulses in this sequence
+ * @first_ts: time stamp of first pulse in usecs
+ * @last_ts: time stamp of last pulse in usecs
+ * @deadline_ts: deadline when this sequence becomes invalid (first_ts + dur)
+ */
+struct pri_sequence {
+ struct list_head head;
+ u32 pri;
+ u32 dur;
+ u32 count;
+ u32 count_falses;
+ u64 first_ts;
+ u64 last_ts;
+ u64 deadline_ts;
+};
+
+/**
+ * struct pulse_elem - elements in pulse queue
+ * @ts: time stamp in usecs
+ */
+struct pulse_elem {
+ struct list_head head;
+ u64 ts;
+};
+
+/**
+ * pde_get_multiple() - get number of multiples considering a given tolerance
+ * @return factor if abs(val - factor*fraction) <= tolerance, 0 otherwise
+ */
+static u32 pde_get_multiple(u32 val, u32 fraction, u32 tolerance)
+{
+ u32 remainder;
+ u32 factor;
+ u32 delta;
+
+ if (fraction == 0)
+ return 0;
+
+ delta = (val < fraction) ? (fraction - val) : (val - fraction);
+
+ if (delta <= tolerance)
+ /* val and fraction are within tolerance */
+ return 1;
+
+ factor = val / fraction;
+ remainder = val % fraction;
+ if (remainder > tolerance) {
+ /* no exact match */
+ if ((fraction - remainder) <= tolerance)
+ /* remainder is within tolerance */
+ factor++;
+ else
+ factor = 0;
+ }
+ return factor;
+}
+
+/**
+ * DOC: Singleton Pulse and Sequence Pools
+ *
+ * Instances of pri_sequence and pulse_elem are kept in singleton pools to
+ * reduce the number of dynamic allocations. They are shared between all
+ * instances and grow up to the peak number of simultaneously used objects.
+ *
+ * Memory is freed after all references to the pools are released.
+ */
+static u32 singleton_pool_references;
+static LIST_HEAD(pulse_pool);
+static LIST_HEAD(pseq_pool);
+
+static struct pulse_elem *pulse_queue_get_tail(struct pri_detector *pde)
+{
+ struct list_head *l = &pde->pulses;
+ if (list_empty(l))
+ return NULL;
+ return list_entry(l->prev, struct pulse_elem, head);
+}
+
+static bool pulse_queue_dequeue(struct pri_detector *pde)
+{
+ struct pulse_elem *p = pulse_queue_get_tail(pde);
+ if (p != NULL) {
+ list_del_init(&p->head);
+ pde->count--;
+ /* give it back to pool */
+ list_add(&p->head, &pulse_pool);
+ }
+ return (pde->count > 0);
+}
+
+/* remove pulses older than window */
+static void pulse_queue_check_window(struct pri_detector *pde)
+{
+ u64 min_valid_ts;
+ struct pulse_elem *p;
+
+ /* there is no delta time with less than 2 pulses */
+ if (pde->count < 2)
+ return;
+
+ if (pde->last_ts <= pde->window_size)
+ return;
+
+ min_valid_ts = pde->last_ts - pde->window_size;
+ while ((p = pulse_queue_get_tail(pde)) != NULL) {
+ if (p->ts >= min_valid_ts)
+ return;
+ pulse_queue_dequeue(pde);
+ }
+}
+
+static bool pulse_queue_enqueue(struct pri_detector *pde, u64 ts)
+{
+ struct pulse_elem *p;
+ if (!list_empty(&pulse_pool)) {
+ p = list_first_entry(&pulse_pool, struct pulse_elem, head);
+ list_del(&p->head);
+ } else {
+ p = kmalloc(sizeof(*p), GFP_KERNEL);
+ if (p == NULL) {
+ pr_err("failed to allocate pulse_elem\n");
+ return false;
+ }
+ }
+ INIT_LIST_HEAD(&p->head);
+ p->ts = ts;
+ list_add(&p->head, &pde->pulses);
+ pde->count++;
+ pde->last_ts = ts;
+ pulse_queue_check_window(pde);
+ if (pde->count >= pde->max_count)
+ pulse_queue_dequeue(pde);
+ return true;
+}
+
+static bool pseq_handler_create_sequences(struct pri_detector *pde,
+ u64 ts, u32 min_count)
+{
+ struct pulse_elem *p;
+ list_for_each_entry(p, &pde->pulses, head) {
+ struct pri_sequence ps, *new_ps;
+ struct pulse_elem *p2;
+ u32 tmp_false_count;
+ u64 min_valid_ts;
+ u32 delta_ts = ts - p->ts;
+
+ if (delta_ts < pde->rs->pri_min)
+ /* ignore too small pri */
+ continue;
+
+ if (delta_ts > pde->rs->pri_max)
+ /* stop on too large pri (sorted list) */
+ break;
+
+ /* build a new sequence with new potential pri */
+ ps.count = 2;
+ ps.count_falses = 0;
+ ps.first_ts = p->ts;
+ ps.last_ts = ts;
+ ps.pri = ts - p->ts;
+ ps.dur = ps.pri * (pde->rs->ppb - 1)
+ + 2 * pde->rs->max_pri_tolerance;
+
+ p2 = p;
+ tmp_false_count = 0;
+ min_valid_ts = ts - ps.dur;
+ /* check which past pulses are candidates for new sequence */
+ list_for_each_entry_continue(p2, &pde->pulses, head) {
+ u32 factor;
+ if (p2->ts < min_valid_ts)
+ /* stop on crossing window border */
+ break;
+ /* check if pulse match (multi)PRI */
+ factor = pde_get_multiple(ps.last_ts - p2->ts, ps.pri,
+ pde->rs->max_pri_tolerance);
+ if (factor > 0) {
+ ps.count++;
+ ps.first_ts = p2->ts;
+ /*
+ * on match, add the intermediate falses
+ * and reset counter
+ */
+ ps.count_falses += tmp_false_count;
+ tmp_false_count = 0;
+ } else {
+ /* this is a potential false one */
+ tmp_false_count++;
+ }
+ }
+ if (ps.count < min_count)
+ /* did not reach minimum count, drop sequence */
+ continue;
+
+ /* this is a valid one, add it */
+ ps.deadline_ts = ps.first_ts + ps.dur;
+
+ if (!list_empty(&pseq_pool)) {
+ new_ps = list_first_entry(&pseq_pool,
+ struct pri_sequence, head);
+ list_del(&new_ps->head);
+ } else {
+ new_ps = kmalloc(sizeof(*new_ps), GFP_KERNEL);
+ if (new_ps == NULL)
+ return false;
+ }
+ memcpy(new_ps, &ps, sizeof(ps));
+ INIT_LIST_HEAD(&new_ps->head);
+ list_add(&new_ps->head, &pde->sequences);
+ }
+ return true;
+}
+
+/* check new ts and add to all matching existing sequences */
+static u32
+pseq_handler_add_to_existing_seqs(struct pri_detector *pde, u64 ts)
+{
+ u32 max_count = 0;
+ struct pri_sequence *ps, *ps2;
+ list_for_each_entry_safe(ps, ps2, &pde->sequences, head) {
+ u32 delta_ts;
+ u32 factor;
+
+ /* first ensure that sequence is within window */
+ if (ts > ps->deadline_ts) {
+ list_del_init(&ps->head);
+ list_add(&ps->head, &pseq_pool);
+ continue;
+ }
+
+ delta_ts = ts - ps->last_ts;
+ factor = pde_get_multiple(delta_ts, ps->pri,
+ pde->rs->max_pri_tolerance);
+ if (factor > 0) {
+ ps->last_ts = ts;
+ ps->count++;
+
+ if (max_count < ps->count)
+ max_count = ps->count;
+ } else {
+ ps->count_falses++;
+ }
+ }
+ return max_count;
+}
+
+static struct pri_sequence *
+pseq_handler_check_detection(struct pri_detector *pde)
+{
+ struct pri_sequence *ps;
+
+ if (list_empty(&pde->sequences))
+ return NULL;
+
+ list_for_each_entry(ps, &pde->sequences, head) {
+ /*
+ * we assume to have enough matching confidence if we
+ * 1) have enough pulses
+ * 2) have more matching than false pulses
+ */
+ if ((ps->count >= pde->rs->ppb_thresh) &&
+ (ps->count * pde->rs->num_pri >= ps->count_falses))
+ return ps;
+ }
+ return NULL;
+}
+
+
+/* free pulse queue and sequences list and give objects back to pools */
+static void pri_detector_reset(struct pri_detector *pde, u64 ts)
+{
+ struct pri_sequence *ps, *ps0;
+ struct pulse_elem *p, *p0;
+ list_for_each_entry_safe(ps, ps0, &pde->sequences, head) {
+ list_del_init(&ps->head);
+ list_add(&ps->head, &pseq_pool);
+ }
+ list_for_each_entry_safe(p, p0, &pde->pulses, head) {
+ list_del_init(&p->head);
+ list_add(&p->head, &pulse_pool);
+ }
+ pde->count = 0;
+ pde->last_ts = ts;
+}
+
+static void pri_detector_exit(struct pri_detector *de)
+{
+ pri_detector_reset(de, 0);
+
+ singleton_pool_references--;
+ if (singleton_pool_references == 0) {
+ /* free singleton pools with no references left */
+ struct pri_sequence *ps, *ps0;
+ struct pulse_elem *p, *p0;
+
+ list_for_each_entry_safe(p, p0, &pulse_pool, head) {
+ list_del(&p->head);
+ kfree(p);
+ }
+ list_for_each_entry_safe(ps, ps0, &pseq_pool, head) {
+ list_del(&ps->head);
+ kfree(ps);
+ }
+ }
+ kfree(de);
+}
+
+static bool pri_detector_add_pulse(struct pri_detector *de,
+ struct pulse_event *event)
+{
+ u32 max_updated_seq;
+ struct pri_sequence *ps;
+ u64 ts = event->ts;
+ const struct radar_detector_specs *rs = de->rs;
+
+ /* ignore pulses not within width range */
+ if ((rs->width_min > event->width) || (rs->width_max < event->width))
+ return false;
+
+ if ((ts - de->last_ts) < rs->max_pri_tolerance)
+ /* if delta to last pulse is too short, don't use this pulse */
+ return false;
+ de->last_ts = ts;
+
+ max_updated_seq = pseq_handler_add_to_existing_seqs(de, ts);
+
+ if (!pseq_handler_create_sequences(de, ts, max_updated_seq)) {
+ pr_err("failed to create pulse sequences\n");
+ pri_detector_reset(de, ts);
+ return false;
+ }
+
+ ps = pseq_handler_check_detection(de);
+
+ if (ps != NULL) {
+ pr_info("DFS: radar found: pri=%d, count=%d, count_false=%d\n",
+ ps->pri, ps->count, ps->count_falses);
+ pri_detector_reset(de, ts);
+ return true;
+ }
+ pulse_queue_enqueue(de, ts);
+ return false;
+}
+
+struct pri_detector *
+pri_detector_init(const struct radar_detector_specs *rs)
+{
+ struct pri_detector *de;
+ de = kzalloc(sizeof(*de), GFP_KERNEL);
+ if (de == NULL)
+ return NULL;
+ de->exit = pri_detector_exit;
+ de->add_pulse = pri_detector_add_pulse;
+ de->reset = pri_detector_reset;
+
+ INIT_LIST_HEAD(&de->sequences);
+ INIT_LIST_HEAD(&de->pulses);
+ de->window_size = rs->pri_max * rs->ppb * rs->num_pri;
+ de->max_count = rs->ppb * 2;
+ de->rs = rs;
+
+ singleton_pool_references++;
+ return de;
+}
--- /dev/null
+/*
+ * Copyright (c) 2012 Neratec Solutions AG
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef DFS_PRI_DETECTOR_H
+#define DFS_PRI_DETECTOR_H
+
+#include <linux/list.h>
+
+/**
+ * struct pri_detector - PRI detector element for a dedicated radar type
+ * @exit(): destructor
+ * @add_pulse(): add pulse event, returns true if pattern was detected
+ * @reset(): clear states and reset to given time stamp
+ * @rs: detector specs for this detector element
+ * @last_ts: last pulse time stamp considered for this element in usecs
+ * @sequences: list_head holding potential pulse sequences
+ * @pulses: list connecting pulse_elem objects
+ * @count: number of pulses in queue
+ * @max_count: maximum number of pulses to be queued
+ * @window_size: window size back from newest pulse time stamp in usecs
+ */
+struct pri_detector {
+ void (*exit) (struct pri_detector *de);
+ bool (*add_pulse)(struct pri_detector *de, struct pulse_event *e);
+ void (*reset) (struct pri_detector *de, u64 ts);
+
+/* private: internal use only */
+ const struct radar_detector_specs *rs;
+ u64 last_ts;
+ struct list_head sequences;
+ struct list_head pulses;
+ u32 count;
+ u32 max_count;
+ u32 window_size;
+};
+
+struct pri_detector *pri_detector_init(const struct radar_detector_specs *rs);
+
+#endif /* DFS_PRI_DETECTOR_H */