/* * 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"#include "ath.h" /** * struct radar_types - contains array of patterns defined for one DFS domain * @region: regulatory DFS region * @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_RATE(PPB, RATE) ((PPB * RATE + 100 - RATE) / 100)#define PPB_THRESH(PPB) PPB_THRESH_RATE(PPB, MIN_PPB_THRESH)#define PRF2PRI(PRF) ((1000000 + PRF / 2) / PRF)/* percentage of pulse width tolerance */#define WIDTH_TOLERANCE 5#define WIDTH_LOWER(X) ((X*(100-WIDTH_TOLERANCE)+50)/100)#define WIDTH_UPPER(X) ((X*(100+WIDTH_TOLERANCE)+50)/100) #define ETSI_PATTERN(ID, WMIN, WMAX, PMIN, PMAX, PRF, PPB, CHIRP)	\{								\	ID, WIDTH_LOWER(WMIN), WIDTH_UPPER(WMAX),		\	(PRF2PRI(PMAX) - PRI_TOLERANCE),			\	(PRF2PRI(PMIN) * PRF + PRI_TOLERANCE), PRF, PPB * PRF,	\	PPB_THRESH(PPB), PRI_TOLERANCE,	CHIRP			\} /* 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, false),	ETSI_PATTERN(1,  0,  5,  200, 1000, 1, 10, false),	ETSI_PATTERN(2,  0, 15,  200, 1600, 1, 15, false),	ETSI_PATTERN(3,  0, 15, 2300, 4000, 1, 25, false),	ETSI_PATTERN(4, 20, 30, 2000, 4000, 1, 20, false),	ETSI_PATTERN(5,  0,  2,  300,  400, 3, 10, false),	ETSI_PATTERN(6,  0,  2,  400, 1200, 3, 15, false),}; 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,}; #define FCC_PATTERN(ID, WMIN, WMAX, PMIN, PMAX, PRF, PPB, CHIRP)	\{								\	ID, WIDTH_LOWER(WMIN), WIDTH_UPPER(WMAX),		\	PMIN - PRI_TOLERANCE,					\	PMAX * PRF + PRI_TOLERANCE, PRF, PPB * PRF,		\	PPB_THRESH(PPB), PRI_TOLERANCE,	CHIRP			\} /* radar types released on August 14, 2014 * type 1 PRI values randomly selected within the range of 518 and 3066. * divide it to 3 groups is good enough for both of radar detection and * avoiding false detection based on practical test results * collected for more than a year. */static const struct radar_detector_specs fcc_radar_ref_types[] = {	FCC_PATTERN(0, 0, 1, 1428, 1428, 1, 18, false),	FCC_PATTERN(101, 0, 1, 518, 938, 1, 57, false),	FCC_PATTERN(102, 0, 1, 938, 2000, 1, 27, false),	FCC_PATTERN(103, 0, 1, 2000, 3066, 1, 18, false),	FCC_PATTERN(2, 0, 5, 150, 230, 1, 23, false),	FCC_PATTERN(3, 6, 10, 200, 500, 1, 16, false),	FCC_PATTERN(4, 11, 20, 200, 500, 1, 12, false),	FCC_PATTERN(5, 50, 100, 1000, 2000, 1, 1, true),	FCC_PATTERN(6, 0, 1, 333, 333, 1, 9, false),}; static const struct radar_types fcc_radar_types = {	.region			= NL80211_DFS_FCC,	.num_radar_types	= ARRAY_SIZE(fcc_radar_ref_types),	.radar_types		= fcc_radar_ref_types,}; #define JP_PATTERN(ID, WMIN, WMAX, PMIN, PMAX, PRF, PPB, RATE, CHIRP)	\{								\	ID, WIDTH_LOWER(WMIN), WIDTH_UPPER(WMAX),		\	PMIN - PRI_TOLERANCE,					\	PMAX * PRF + PRI_TOLERANCE, PRF, PPB * PRF,		\	PPB_THRESH_RATE(PPB, RATE), PRI_TOLERANCE, CHIRP	\}static const struct radar_detector_specs jp_radar_ref_types[] = {	JP_PATTERN(0, 0, 1, 1428, 1428, 1, 18, 29, false),	JP_PATTERN(1, 2, 3, 3846, 3846, 1, 18, 29, false),	JP_PATTERN(2, 0, 1, 1388, 1388, 1, 18, 50, false),	JP_PATTERN(3, 0, 4, 4000, 4000, 1, 18, 50, false),	JP_PATTERN(4, 0, 5, 150, 230, 1, 23, 50, false),	JP_PATTERN(5, 6, 10, 200, 500, 1, 16, 50, false),	JP_PATTERN(6, 11, 20, 200, 500, 1, 12, 50, false),	JP_PATTERN(7, 50, 100, 1000, 2000, 1, 3, 50, true),	JP_PATTERN(5, 0, 1, 333, 333, 1, 9, 50, false),}; static const struct radar_types jp_radar_types = {	.region			= NL80211_DFS_JP,	.num_radar_types	= ARRAY_SIZE(jp_radar_ref_types),	.radar_types		= jp_radar_ref_types,}; static const struct radar_types *dfs_domains[] = {	&etsi_radar_types_v15,	&fcc_radar_types,	&jp_radar_types,}; /** * get_dfs_domain_radar_types() - get radar types for a given DFS domain * @region: regulatory DFS region * * Return value: 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);} static struct channel_detector *channel_detector_create(struct dfs_pattern_detector *dpd, u16 freq){	u32 i;	struct channel_detector *cd; 	cd = kzalloc_flex(*cd, detectors, dpd->num_radar_types, GFP_ATOMIC);	if (cd == NULL)		goto fail; 	INIT_LIST_HEAD(&cd->head);	cd->freq = freq; 	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:	ath_dbg(dpd->common, DFS,		"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 * @dpd: DPD instance pointer * @freq: freq frequency in MHz * * Return value: 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;	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;	list_for_each_entry_safe(cd, cd0, &dpd->channel_detectors, head)		channel_detector_exit(dpd, cd);	kfree(dpd);} static booldpd_add_pulse(struct dfs_pattern_detector *dpd, struct pulse_event *event,	      struct radar_detector_specs *rs){	u32 i;	struct channel_detector *cd; 	/*	 * pulses received for a non-supported or un-initialized	 * domain are treated as detected radars for fail-safety	 */	if (dpd->region == NL80211_DFS_UNSET)		return true; 	cd = channel_detector_get(dpd, event->freq);	if (cd == NULL)		return false; 	/* reset detector on time stamp wraparound, caused by TSF reset */	if (event->ts < dpd->last_pulse_ts)		dpd_reset(dpd);	dpd->last_pulse_ts = event->ts; 	/* do type individual pattern matching */	for (i = 0; i < dpd->num_radar_types; i++) {		struct pri_detector *pd = cd->detectors[i];		struct pri_sequence *ps = pd->add_pulse(pd, event);		if (ps != NULL) {			if (rs != NULL)				memcpy(rs, pd->rs, sizeof(*rs));			ath_dbg(dpd->common, DFS,				"DFS: radar found on freq=%d: id=%d, pri=%d, "				"count=%d, count_false=%d\n",				event->freq, pd->rs->type_id,				ps->pri, ps->count, ps->count_falses);			pd->reset(pd, dpd->last_pulse_ts);			return true;		}	}	return false;} static struct ath_dfs_pool_statsdpd_get_stats(struct dfs_pattern_detector *dpd){	return global_dfs_pool_stats;} 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 */	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 const struct dfs_pattern_detector default_dpd = {	.exit		= dpd_exit,	.set_dfs_domain	= dpd_set_domain,	.add_pulse	= dpd_add_pulse,	.get_stats	= dpd_get_stats,	.region		= NL80211_DFS_UNSET,}; struct dfs_pattern_detector *dfs_pattern_detector_init(struct ath_common *common,			  enum nl80211_dfs_regions region){	struct dfs_pattern_detector *dpd; 	if (!IS_ENABLED(CONFIG_CFG80211_CERTIFICATION_ONUS))		return NULL; 	dpd = kmalloc_obj(*dpd);	if (dpd == NULL)		return NULL; 	*dpd = default_dpd;	INIT_LIST_HEAD(&dpd->channel_detectors); 	dpd->common = common;	if (dpd->set_dfs_domain(dpd, region))		return dpd; 	ath_dbg(common, DFS,"Could not set DFS domain to %d", region);	kfree(dpd);	return NULL;}EXPORT_SYMBOL(dfs_pattern_detector_init);