nl80211/cfg80211: add match filtering for sched_scan

Introduce filtering for scheduled scans to reduce the number of
unnecessary results (which cause useless wake-ups).

Add a new nested attribute where sets of parameters to be matched can
be passed when starting a scheduled scan.  Only scan results that
match any of the sets will be returned.

At this point, the set consists of a single parameter, an SSID.  This
can be easily extended in the future to support more complex matches.

Signed-off-by: Luciano Coelho <coelho@ti.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 01c6bde99a41..09024ab617f9 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -876,6 +876,15 @@ struct cfg80211_scan_request {
 };
 
 /**
+ * struct cfg80211_match_set - sets of attributes to match
+ *
+ * @ssid: SSID to be matched
+ */
+struct cfg80211_match_set {
+	struct cfg80211_ssid ssid;
+};
+
+/**
  * struct cfg80211_sched_scan_request - scheduled scan request description
  *
  * @ssids: SSIDs to scan for (passed in the probe_reqs in active scans)
@@ -884,6 +893,11 @@ struct cfg80211_scan_request {
  * @interval: interval between each scheduled scan cycle
  * @ie: optional information element(s) to add into Probe Request or %NULL
  * @ie_len: length of ie in octets
+ * @match_sets: sets of parameters to be matched for a scan result
+ * 	entry to be considered valid and to be passed to the host
+ * 	(others are filtered out).
+ *	If ommited, all results are passed.
+ * @n_match_sets: number of match sets
  * @wiphy: the wiphy this was for
  * @dev: the interface
  * @channels: channels to scan
@@ -895,6 +909,8 @@ struct cfg80211_sched_scan_request {
 	u32 interval;
 	const u8 *ie;
 	size_t ie_len;
+	struct cfg80211_match_set *match_sets;
+	int n_match_sets;
 
 	/* internal */
 	struct wiphy *wiphy;
@@ -1814,6 +1830,9 @@ struct wiphy_wowlan_support {
  *	any given scan
  * @max_sched_scan_ssids: maximum number of SSIDs the device can scan
  *	for in any given scheduled scan
+ * @max_match_sets: maximum number of match sets the device can handle
+ *	when performing a scheduled scan, 0 if filtering is not
+ *	supported.
  * @max_scan_ie_len: maximum length of user-controlled IEs device can
  *	add to probe request frames transmitted during a scan, must not
  *	include fixed IEs like supported rates
@@ -1871,6 +1890,7 @@ struct wiphy {
 	int bss_priv_size;
 	u8 max_scan_ssids;
 	u8 max_sched_scan_ssids;
+	u8 max_match_sets;
 	u16 max_scan_ie_len;
 	u16 max_sched_scan_ie_len;