mac80211: add helper functions for tracking P2P NoA state (a7022e65) · Commits · e / devices / android_kernel_xiaomi_markw

include/net/mac80211.h

+47 −0

Original line number	Diff line number	Diff line
		@@ -4652,4 +4652,51 @@ bool ieee80211_tx_prepare_skb(struct ieee80211_hw *hw,
		struct ieee80211_vif vif, struct sk_buff skb,
		int band, struct ieee80211_sta **sta);

		/**
		* struct ieee80211_noa_data - holds temporary data for tracking P2P NoA state
		*
		* @next_tsf: TSF timestamp of the next absent state change
		* @has_next_tsf: next absent state change event pending
		*
		* @absent: descriptor bitmask, set if GO is currently absent
		*
		* private:
		*
		* @count: count fields from the NoA descriptors
		* @desc: adjusted data from the NoA
		*/
		struct ieee80211_noa_data {
		u32 next_tsf;
		bool has_next_tsf;

		u8 absent;

		u8 count[IEEE80211_P2P_NOA_DESC_MAX];
		struct {
		u32 start;
		u32 duration;
		u32 interval;
		} desc[IEEE80211_P2P_NOA_DESC_MAX];
		};

		/**
		* ieee80211_parse_p2p_noa - initialize NoA tracking data from P2P IE
		*
		* @attr: P2P NoA IE
		* @data: NoA tracking data
		* @tsf: current TSF timestamp
		*
		* Return: number of successfully parsed descriptors
		*/
		int ieee80211_parse_p2p_noa(const struct ieee80211_p2p_noa_attr *attr,
		struct ieee80211_noa_data *data, u32 tsf);

		/**
		* ieee80211_update_p2p_noa - get next pending P2P GO absent state change
		*
		* @data: NoA tracking data
		* @tsf: current TSF timestamp
		*/
		void ieee80211_update_p2p_noa(struct ieee80211_noa_data *data, u32 tsf);

		#endif /* MAC80211_H */

net/mac80211/util.c

+140 −0

Original line number	Diff line number	Diff line
		@@ -2594,3 +2594,143 @@ int ieee80211_cs_headroom(struct ieee80211_local *local,

		return headroom;
		}

		static bool
		ieee80211_extend_noa_desc(struct ieee80211_noa_data *data, u32 tsf, int i)
		{
		s32 end = data->desc[i].start + data->desc[i].duration - (tsf + 1);
		int skip;

		if (end > 0)
		return false;

		/* End time is in the past, check for repetitions */
		skip = DIV_ROUND_UP(-end, data->desc[i].interval);
		if (data->count[i] < 255) {
		if (data->count[i] <= skip) {
		data->count[i] = 0;
		return false;
		}

		data->count[i] -= skip;
		}

		data->desc[i].start += skip * data->desc[i].interval;

		return true;
		}

		static bool
		ieee80211_extend_absent_time(struct ieee80211_noa_data *data, u32 tsf,
		s32 *offset)
		{
		bool ret = false;
		int i;

		for (i = 0; i < IEEE80211_P2P_NOA_DESC_MAX; i++) {
		s32 cur;

		if (!data->count[i])
		continue;

		if (ieee80211_extend_noa_desc(data, tsf + *offset, i))
		ret = true;

		cur = data->desc[i].start - tsf;
		if (cur > *offset)
		continue;

		cur = data->desc[i].start + data->desc[i].duration - tsf;
		if (cur > *offset)
		*offset = cur;
		}

		return ret;
		}

		static u32
		ieee80211_get_noa_absent_time(struct ieee80211_noa_data *data, u32 tsf)
		{
		s32 offset = 0;
		int tries = 0;
		/*
		* arbitrary limit, used to avoid infinite loops when combined NoA
		* descriptors cover the full time period.
		*/
		int max_tries = 5;

		ieee80211_extend_absent_time(data, tsf, &offset);
		do {
		if (!ieee80211_extend_absent_time(data, tsf, &offset))
		break;

		tries++;
		} while (tries < max_tries);

		return offset;
		}

		void ieee80211_update_p2p_noa(struct ieee80211_noa_data *data, u32 tsf)
		{
		u32 next_offset = BIT(31) - 1;
		int i;

		data->absent = 0;
		data->has_next_tsf = false;
		for (i = 0; i < IEEE80211_P2P_NOA_DESC_MAX; i++) {
		s32 start;

		if (!data->count[i])
		continue;

		ieee80211_extend_noa_desc(data, tsf, i);
		start = data->desc[i].start - tsf;
		if (start <= 0)
		data->absent \|= BIT(i);

		if (next_offset > start)
		next_offset = start;

		data->has_next_tsf = true;
		}

		if (data->absent)
		next_offset = ieee80211_get_noa_absent_time(data, tsf);

		data->next_tsf = tsf + next_offset;
		}
		EXPORT_SYMBOL(ieee80211_update_p2p_noa);

		int ieee80211_parse_p2p_noa(const struct ieee80211_p2p_noa_attr *attr,
		struct ieee80211_noa_data *data, u32 tsf)
		{
		int ret = 0;
		int i;

		memset(data, 0, sizeof(*data));

		for (i = 0; i < IEEE80211_P2P_NOA_DESC_MAX; i++) {
		const struct ieee80211_p2p_noa_desc *desc = &attr->desc[i];

		if (!desc->count \|\| !desc->duration)
		continue;

		data->count[i] = desc->count;
		data->desc[i].start = le32_to_cpu(desc->start_time);
		data->desc[i].duration = le32_to_cpu(desc->duration);
		data->desc[i].interval = le32_to_cpu(desc->interval);

		if (data->count[i] > 1 &&
		data->desc[i].interval < data->desc[i].duration)
		continue;

		ieee80211_extend_noa_desc(data, tsf, i);
		ret++;
		}

		if (ret)
		ieee80211_update_p2p_noa(data, tsf);

		return ret;
		}
		EXPORT_SYMBOL(ieee80211_parse_p2p_noa);