6 files changed, 139 insertions, 0 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2500usb.c b/drivers/net/wireless/rt2x00/rt2500usb.c
index b21f81231a09..15237c275486 100644
--- a/drivers/net/wireless/rt2x00/rt2500usb.c
+++ b/drivers/net/wireless/rt2x00/rt2500usb.c
@@ -1797,6 +1797,7 @@ static int rt2500usb_probe_hw(struct rt2x00_dev *rt2x00dev)
                 __set_bit(REQUIRE_COPY_IV, &rt2x00dev->cap_flags);
         }
         __set_bit(REQUIRE_SW_SEQNO, &rt2x00dev->cap_flags);
+        __set_bit(REQUIRE_PS_AUTOWAKE, &rt2x00dev->cap_flags);
 
         /*
          * Set the rssi offset.
diff --git a/drivers/net/wireless/rt2x00/rt2800usb.c b/drivers/net/wireless/rt2x00/rt2800usb.c
index b5d5f2203c52..0eb44cf2f44a 100644
--- a/drivers/net/wireless/rt2x00/rt2800usb.c
+++ b/drivers/net/wireless/rt2x00/rt2800usb.c
@@ -634,6 +634,7 @@ static int rt2800usb_probe_hw(struct rt2x00_dev *rt2x00dev)
         __set_bit(CAPABILITY_LINK_TUNING, &rt2x00dev->cap_flags);
         __set_bit(REQUIRE_HT_TX_DESC, &rt2x00dev->cap_flags);
         __set_bit(REQUIRE_TXSTATUS_FIFO, &rt2x00dev->cap_flags);
+        __set_bit(REQUIRE_PS_AUTOWAKE, &rt2x00dev->cap_flags);
 
         setup_timer(&rt2x00dev->txstatus_timer,
                     rt2800usb_tx_sta_fifo_timeout,
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 86e141000156..73d3332be614 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -662,6 +662,7 @@ enum rt2x00_state_flags {
          * Driver configuration
          */
         CONFIG_CHANNEL_HT40,
+        CONFIG_POWERSAVING,
 };
 
 /*
@@ -681,6 +682,7 @@ enum rt2x00_capability_flags {
         REQUIRE_TASKLET_CONTEXT,
         REQUIRE_SW_SEQNO,
         REQUIRE_HT_TX_DESC,
+        REQUIRE_PS_AUTOWAKE,
 
         /*
          * Capabilities
@@ -875,10 +877,20 @@ struct rt2x00_dev {
         u8 calibration[2];
 
         /*
+         * Association id.
+         */
+        u16 aid;
+
+        /*
          * Beacon interval.
          */
         u16 beacon_int;
 
+        /**
+         * Timestamp of last received beacon
+         */
+        unsigned long last_beacon;
+
         /*
          * Low level statistics which will have
          * to be kept up to date while device is running.
@@ -907,6 +919,11 @@ struct rt2x00_dev {
         struct work_struct txdone_work;
 
         /*
+         * Powersaving work
+         */
+        struct delayed_work autowakeup_work;
+
+        /*
          * Data queue arrays for RX, TX, Beacon and ATIM.
          */
         unsigned int data_queues;
diff --git a/drivers/net/wireless/rt2x00/rt2x00config.c b/drivers/net/wireless/rt2x00/rt2x00config.c
index 2a313b6d378d..edebbf04bc57 100644
--- a/drivers/net/wireless/rt2x00/rt2x00config.c
+++ b/drivers/net/wireless/rt2x00/rt2x00config.c
@@ -100,6 +100,10 @@ void rt2x00lib_config_erp(struct rt2x00_dev *rt2x00dev,
         erp.basic_rates = bss_conf->basic_rates;
         erp.beacon_int = bss_conf->beacon_int;
 
+        /* Update the AID, this is needed for dynamic PS support */
+        rt2x00dev->aid = bss_conf->assoc ? bss_conf->aid : 0;
+        rt2x00dev->last_beacon = bss_conf->timestamp;
+
         /* Update global beacon interval time, this is needed for PS support */
         rt2x00dev->beacon_int = bss_conf->beacon_int;
 
@@ -204,6 +208,9 @@ void rt2x00lib_config(struct rt2x00_dev *rt2x00dev,
 {
         struct rt2x00lib_conf libconf;
         u16 hw_value;
+        u16 autowake_timeout;
+        u16 beacon_int;
+        u16 beacon_diff;
 
         memset(&libconf, 0, sizeof(libconf));
 
@@ -227,6 +234,10 @@ void rt2x00lib_config(struct rt2x00_dev *rt2x00dev,
                        sizeof(libconf.channel));
         }
 
+        if (test_bit(REQUIRE_PS_AUTOWAKE, &rt2x00dev->cap_flags) &&
+            (ieee80211_flags & IEEE80211_CONF_CHANGE_PS))
+                cancel_delayed_work_sync(&rt2x00dev->autowakeup_work);
+
         /*
          * Start configuration.
          */
@@ -239,6 +250,26 @@ void rt2x00lib_config(struct rt2x00_dev *rt2x00dev,
         if (ieee80211_flags & IEEE80211_CONF_CHANGE_CHANNEL)
                 rt2x00link_reset_tuner(rt2x00dev, false);
 
+        if (test_bit(REQUIRE_PS_AUTOWAKE, &rt2x00dev->cap_flags) &&
+            (ieee80211_flags & IEEE80211_CONF_CHANGE_PS) &&
+            (conf->flags & IEEE80211_CONF_PS)) {
+                beacon_diff = (long)jiffies - (long)rt2x00dev->last_beacon;
+                beacon_int = msecs_to_jiffies(rt2x00dev->beacon_int);
+
+                if (beacon_diff > beacon_int)
+                        beacon_diff = 0;
+
+                autowake_timeout = (conf->max_sleep_period * beacon_int) - beacon_diff;
+                queue_delayed_work(rt2x00dev->workqueue,
+                                   &rt2x00dev->autowakeup_work,
+                                   autowake_timeout - 15);
+        }
+
+        if (conf->flags & IEEE80211_CONF_PS)
+                set_bit(CONFIG_POWERSAVING, &rt2x00dev->flags);
+        else
+                clear_bit(CONFIG_POWERSAVING, &rt2x00dev->flags);
+
         rt2x00dev->curr_band = conf->channel->band;
         rt2x00dev->curr_freq = conf->channel->center_freq;
         rt2x00dev->tx_power = conf->power_level;
diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
index 7776d9f1f297..2eb5196977fd 100644
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
@@ -141,6 +141,16 @@ static void rt2x00lib_intf_scheduled(struct work_struct *work)
                                             rt2x00dev);
 }
 
+static void rt2x00lib_autowakeup(struct work_struct *work)
+{
+        struct rt2x00_dev *rt2x00dev =
+            container_of(work, struct rt2x00_dev, autowakeup_work.work);
+
+        if (rt2x00dev->ops->lib->set_device_state(rt2x00dev, STATE_AWAKE))
+                ERROR(rt2x00dev, "Device failed to wakeup.\n");
+        clear_bit(CONFIG_POWERSAVING, &rt2x00dev->flags);
+}
+
 /*
  * Interrupt context handlers.
  */
@@ -416,6 +426,77 @@ void rt2x00lib_txdone_noinfo(struct queue_entry *entry, u32 status)
 }
 EXPORT_SYMBOL_GPL(rt2x00lib_txdone_noinfo);
 
+static u8 *rt2x00lib_find_ie(u8 *data, unsigned int len, u8 ie)
+{
+        struct ieee80211_mgmt *mgmt = (void *)data;
+        u8 *pos, *end;
+
+        pos = (u8 *)mgmt->u.beacon.variable;
+        end = data + len;
+        while (pos < end) {
+                if (pos + 2 + pos[1] > end)
+                        return NULL;
+
+                if (pos[0] == ie)
+                        return pos;
+
+                pos += 2 + pos[1];
+        }
+
+        return NULL;
+}
+
+static void rt2x00lib_rxdone_check_ps(struct rt2x00_dev *rt2x00dev,
+                                      struct sk_buff *skb,
+                                      struct rxdone_entry_desc *rxdesc)
+{
+        struct ieee80211_hdr *hdr = (void *) skb->data;
+        struct ieee80211_tim_ie *tim_ie;
+        u8 *tim;
+        u8 tim_len;
+        bool cam;
+
+        /* If this is not a beacon, or if mac80211 has no powersaving
+         * configured, or if the device is already in powersaving mode
+         * we can exit now. */
+        if (likely(!ieee80211_is_beacon(hdr->frame_control) ||
+                   !(rt2x00dev->hw->conf.flags & IEEE80211_CONF_PS)))
+                return;
+
+        /* min. beacon length + FCS_LEN */
+        if (skb->len <= 40 + FCS_LEN)
+                return;
+
+        /* and only beacons from the associated BSSID, please */
+        if (!(rxdesc->dev_flags & RXDONE_MY_BSS) ||
+            !rt2x00dev->aid)
+                return;
+
+        rt2x00dev->last_beacon = jiffies;
+
+        tim = rt2x00lib_find_ie(skb->data, skb->len - FCS_LEN, WLAN_EID_TIM);
+        if (!tim)
+                return;
+
+        if (tim[1] < sizeof(*tim_ie))
+                return;
+
+        tim_len = tim[1];
+        tim_ie = (struct ieee80211_tim_ie *) &tim[2];
+
+        /* Check whenever the PHY can be turned off again. */
+
+        /* 1. What about buffered unicast traffic for our AID? */
+        cam = ieee80211_check_tim(tim_ie, tim_len, rt2x00dev->aid);
+
+        /* 2. Maybe the AP wants to send multicast/broadcast data? */
+        cam |= (tim_ie->bitmap_ctrl & 0x01);
+
+        if (!cam && !test_bit(CONFIG_POWERSAVING, &rt2x00dev->flags))
+                rt2x00lib_config(rt2x00dev, &rt2x00dev->hw->conf,
+                                 IEEE80211_CONF_CHANGE_PS);
+}
+
 static int rt2x00lib_rxdone_read_signal(struct rt2x00_dev *rt2x00dev,
                                         struct rxdone_entry_desc *rxdesc)
 {
@@ -531,6 +612,12 @@ void rt2x00lib_rxdone(struct queue_entry *entry)
                 rxdesc.flags |= RX_FLAG_HT;
 
         /*
+         * Check if this is a beacon, and more frames have been
+         * buffered while we were in powersaving mode.
+         */
+        rt2x00lib_rxdone_check_ps(rt2x00dev, entry->skb, &rxdesc);
+
+        /*
          * Update extra components
          */
         rt2x00link_update_stats(rt2x00dev, entry->skb, &rxdesc);
@@ -1017,6 +1104,7 @@ int rt2x00lib_probe_dev(struct rt2x00_dev *rt2x00dev)
         }
 
         INIT_WORK(&rt2x00dev->intf_work, rt2x00lib_intf_scheduled);
+        INIT_DELAYED_WORK(&rt2x00dev->autowakeup_work, rt2x00lib_autowakeup);
 
         /*
          * Let the driver probe the device to detect the capabilities.
diff --git a/drivers/net/wireless/rt2x00/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index a6ce7d6cbdfa..ad20953cbf05 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -2209,6 +2209,7 @@ static int rt73usb_probe_hw(struct rt2x00_dev *rt2x00dev)
         if (!modparam_nohwcrypt)
                 __set_bit(CAPABILITY_HW_CRYPTO, &rt2x00dev->cap_flags);
         __set_bit(CAPABILITY_LINK_TUNING, &rt2x00dev->cap_flags);
+        __set_bit(REQUIRE_PS_AUTOWAKE, &rt2x00dev->cap_flags);
 
         /*
          * Set the rssi offset.