mac80211: enable spatial multiplexing powersave

Enable spatial multiplexing in mac80211 by telling the
driver what to do and, where necessary, sending action
frames to the AP to update the requested SMPS mode.

Also includes a trivial implementation for hwsim that
just logs the requested mode.

For now, the userspace interface is in debugfs only,
and let you toggle the requested mode at any time.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 59 insertions, 4 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index cd5dcc3d8c2b..0a762a9ba4df 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -398,6 +398,8 @@ static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata,
                 __le16 tmp;
                 u32 flags = local->hw.conf.channel->flags;
 
+                /* determine capability flags */
+
                 switch (ht_info->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
                 case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
                         if (flags & IEEE80211_CHAN_NO_HT40PLUS) {
@@ -413,17 +415,64 @@ static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata,
                         break;
                 }
 
-                tmp = cpu_to_le16(cap);
-                pos = skb_put(skb, sizeof(struct ieee80211_ht_cap)+2);
+                /* set SM PS mode properly */
+                cap &= ~IEEE80211_HT_CAP_SM_PS;
+                /* new association always uses requested smps mode */
+                if (ifmgd->req_smps == IEEE80211_SMPS_AUTOMATIC) {
+                        if (ifmgd->powersave)
+                                ifmgd->ap_smps = IEEE80211_SMPS_DYNAMIC;
+                        else
+                                ifmgd->ap_smps = IEEE80211_SMPS_OFF;
+                } else
+                        ifmgd->ap_smps = ifmgd->req_smps;
+
+                switch (ifmgd->ap_smps) {
+                case IEEE80211_SMPS_AUTOMATIC:
+                case IEEE80211_SMPS_NUM_MODES:
+                        WARN_ON(1);
+                case IEEE80211_SMPS_OFF:
+                        cap |= WLAN_HT_CAP_SM_PS_DISABLED <<
+                                IEEE80211_HT_CAP_SM_PS_SHIFT;
+                        break;
+                case IEEE80211_SMPS_STATIC:
+                        cap |= WLAN_HT_CAP_SM_PS_STATIC <<
+                                IEEE80211_HT_CAP_SM_PS_SHIFT;
+                        break;
+                case IEEE80211_SMPS_DYNAMIC:
+                        cap |= WLAN_HT_CAP_SM_PS_DYNAMIC <<
+                                IEEE80211_HT_CAP_SM_PS_SHIFT;
+                        break;
+                }
+
+                /* reserve and fill IE */
+
+                pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
                 *pos++ = WLAN_EID_HT_CAPABILITY;
                 *pos++ = sizeof(struct ieee80211_ht_cap);
                 memset(pos, 0, sizeof(struct ieee80211_ht_cap));
+
+                /* capability flags */
+                tmp = cpu_to_le16(cap);
                 memcpy(pos, &tmp, sizeof(u16));
                 pos += sizeof(u16);
-                /* TODO: needs a define here for << 2 */
+
+                /* AMPDU parameters */
                 *pos++ = sband->ht_cap.ampdu_factor |
-                         (sband->ht_cap.ampdu_density << 2);
+                         (sband->ht_cap.ampdu_density <<
+                                IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT);
+
+                /* MCS set */
                 memcpy(pos, &sband->ht_cap.mcs, sizeof(sband->ht_cap.mcs));
+                pos += sizeof(sband->ht_cap.mcs);
+
+                /* extended capabilities */
+                pos += sizeof(__le16);
+
+                /* BF capabilities */
+                pos += sizeof(__le32);
+
+                /* antenna selection */
+                pos += sizeof(u8);
         }
 
         IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
@@ -932,6 +981,7 @@ static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
 
         mutex_lock(&local->iflist_mtx);
         ieee80211_recalc_ps(local, -1);
+        ieee80211_recalc_smps(local, sdata);
         mutex_unlock(&local->iflist_mtx);
 
         netif_start_queue(sdata->dev);
@@ -2327,6 +2377,11 @@ void ieee80211_sta_setup_sdata(struct ieee80211_sub_if_data *sdata)
                 ifmgd->flags |= IEEE80211_STA_WMM_ENABLED;
 
         mutex_init(&ifmgd->mtx);
+
+        if (sdata->local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_SMPS)
+                ifmgd->req_smps = IEEE80211_SMPS_AUTOMATIC;
+        else
+                ifmgd->req_smps = IEEE80211_SMPS_OFF;
 }
 
 /* scan finished notification */