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path: root/drivers/net/wireless/ath/ath9k/dfs_pri_detector.c
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Diffstat (limited to 'drivers/net/wireless/ath/ath9k/dfs_pri_detector.c')
-rw-r--r--drivers/net/wireless/ath/ath9k/dfs_pri_detector.c425
1 files changed, 0 insertions, 425 deletions
diff --git a/drivers/net/wireless/ath/ath9k/dfs_pri_detector.c b/drivers/net/wireless/ath/ath9k/dfs_pri_detector.c
deleted file mode 100644
index 5ba4b6fe37c0..000000000000
--- a/drivers/net/wireless/ath/ath9k/dfs_pri_detector.c
+++ /dev/null
@@ -1,425 +0,0 @@
-/*
- * 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/spinlock.h>
-
-#include "ath9k.h"
-#include "dfs_pattern_detector.h"
-#include "dfs_pri_detector.h"
-#include "dfs_debug.h"
-
-/**
- * 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 DEFINE_SPINLOCK(pool_lock);
-
-static void pool_register_ref(void)
-{
- spin_lock_bh(&pool_lock);
- singleton_pool_references++;
- DFS_POOL_STAT_INC(pool_reference);
- spin_unlock_bh(&pool_lock);
-}
-
-static void pool_deregister_ref(void)
-{
- spin_lock_bh(&pool_lock);
- singleton_pool_references--;
- DFS_POOL_STAT_DEC(pool_reference);
- 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);
- DFS_POOL_STAT_DEC(pulse_allocated);
- kfree(p);
- }
- list_for_each_entry_safe(ps, ps0, &pseq_pool, head) {
- list_del(&ps->head);
- DFS_POOL_STAT_DEC(pseq_allocated);
- kfree(ps);
- }
- }
- spin_unlock_bh(&pool_lock);
-}
-
-static void pool_put_pulse_elem(struct pulse_elem *pe)
-{
- spin_lock_bh(&pool_lock);
- list_add(&pe->head, &pulse_pool);
- DFS_POOL_STAT_DEC(pulse_used);
- spin_unlock_bh(&pool_lock);
-}
-
-static void pool_put_pseq_elem(struct pri_sequence *pse)
-{
- spin_lock_bh(&pool_lock);
- list_add(&pse->head, &pseq_pool);
- DFS_POOL_STAT_DEC(pseq_used);
- spin_unlock_bh(&pool_lock);
-}
-
-static struct pri_sequence *pool_get_pseq_elem(void)
-{
- struct pri_sequence *pse = NULL;
- spin_lock_bh(&pool_lock);
- if (!list_empty(&pseq_pool)) {
- pse = list_first_entry(&pseq_pool, struct pri_sequence, head);
- list_del(&pse->head);
- DFS_POOL_STAT_INC(pseq_used);
- }
- spin_unlock_bh(&pool_lock);
- return pse;
-}
-
-static struct pulse_elem *pool_get_pulse_elem(void)
-{
- struct pulse_elem *pe = NULL;
- spin_lock_bh(&pool_lock);
- if (!list_empty(&pulse_pool)) {
- pe = list_first_entry(&pulse_pool, struct pulse_elem, head);
- list_del(&pe->head);
- DFS_POOL_STAT_INC(pulse_used);
- }
- spin_unlock_bh(&pool_lock);
- return pe;
-}
-
-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 */
- pool_put_pulse_elem(p);
- }
- 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 = pool_get_pulse_elem();
- if (p == NULL) {
- p = kmalloc(sizeof(*p), GFP_ATOMIC);
- if (p == NULL) {
- DFS_POOL_STAT_INC(pulse_alloc_error);
- return false;
- }
- DFS_POOL_STAT_INC(pulse_allocated);
- DFS_POOL_STAT_INC(pulse_used);
- }
- 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;
- new_ps = pool_get_pseq_elem();
- if (new_ps == NULL) {
- new_ps = kmalloc(sizeof(*new_ps), GFP_ATOMIC);
- if (new_ps == NULL) {
- DFS_POOL_STAT_INC(pseq_alloc_error);
- return false;
- }
- DFS_POOL_STAT_INC(pseq_allocated);
- DFS_POOL_STAT_INC(pseq_used);
- }
- 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);
- pool_put_pseq_elem(ps);
- 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);
- pool_put_pseq_elem(ps);
- }
- list_for_each_entry_safe(p, p0, &pde->pulses, head) {
- list_del_init(&p->head);
- pool_put_pulse_elem(p);
- }
- pde->count = 0;
- pde->last_ts = ts;
-}
-
-static void pri_detector_exit(struct pri_detector *de)
-{
- pri_detector_reset(de, 0);
- pool_deregister_ref();
- kfree(de);
-}
-
-static struct pri_sequence *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 NULL;
-
- if ((ts - de->last_ts) < rs->max_pri_tolerance)
- /* if delta to last pulse is too short, don't use this pulse */
- return NULL;
- 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)) {
- pri_detector_reset(de, ts);
- return false;
- }
-
- ps = pseq_handler_check_detection(de);
-
- if (ps == NULL)
- pulse_queue_enqueue(de, ts);
-
- return ps;
-}
-
-struct pri_detector *pri_detector_init(const struct radar_detector_specs *rs)
-{
- struct pri_detector *de;
-
- de = kzalloc(sizeof(*de), GFP_ATOMIC);
- 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;
-
- pool_register_ref();
- return de;
-}