mac80211: add U-APSD client support
Add Unscheduled Automatic Power-Save Delivery (U-APSD) client support. The
idea is that the data frames from the client trigger AP to send the buffered
frames with ACs which have U-APSD enabled. This decreases latency and makes it
possible to save even more power.
Driver needs to use IEEE80211_HW_UAPSD to enable the feature. The current
implementation assumes that firmware takes care of the wakeup and
hardware needing IEEE80211_HW_PS_NULLFUNC_STACK is not yet supported.
Tested with wl1251 on a Nokia N900 and Cisco Aironet 1231G AP and running
various test traffic with ping.
Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 30cb62b..9afe2f9 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -54,6 +54,23 @@
cfg80211_put_bss(container_of((void *)bss, struct cfg80211_bss, priv));
}
+static bool is_uapsd_supported(struct ieee802_11_elems *elems)
+{
+ u8 qos_info;
+
+ if (elems->wmm_info && elems->wmm_info_len == 7
+ && elems->wmm_info[5] == 1)
+ qos_info = elems->wmm_info[6];
+ else if (elems->wmm_param && elems->wmm_param_len == 24
+ && elems->wmm_param[5] == 1)
+ qos_info = elems->wmm_param[6];
+ else
+ /* no valid wmm information or parameter element found */
+ return false;
+
+ return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD;
+}
+
struct ieee80211_bss *
ieee80211_bss_info_update(struct ieee80211_local *local,
struct ieee80211_rx_status *rx_status,
@@ -117,6 +134,7 @@
}
bss->wmm_used = elems->wmm_param || elems->wmm_info;
+ bss->uapsd_supported = is_uapsd_supported(elems);
if (!beacon)
bss->last_probe_resp = jiffies;