mac80211: add helper functions for tracking P2P NoA state
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index ed93504..df00f19 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -2594,3 +2594,143 @@
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);