mac80211: add basic support for WoWLAN

This adds basic support for the new WoWLAN
configuration in mac80211. The behaviour is
completely offloaded to the driver though,
with two new callbacks (suspend/resume).

Options for the driver include a complete
reconfiguration after wakeup, and exposing
all the triggers it wants to support.

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

9 files changed, 97 insertions, 5 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 63f75a06043b..9e5542794b95 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1606,6 +1606,18 @@ enum ieee80211_ampdu_mlme_action {
  *      you should ensure to cancel it on this callback.
  *      Must be implemented and can sleep.
  *
+ * @suspend: Suspend the device; mac80211 itself will quiesce before and
+ *      stop transmitting and doing any other configuration, and then
+ *      ask the device to suspend. This is only invoked when WoWLAN is
+ *      configured, otherwise the device is deconfigured completely and
+ *      reconfigured at resume time.
+ *
+ * @resume: If WoWLAN was configured, this indicates that mac80211 is
+ *      now resuming its operation, after this the device must be fully
+ *      functional again. If this returns an error, the only way out is
+ *      to also unregister the device. If it returns 1, then mac80211
+ *      will also go through the regular complete restart on resume.
+ *
  * @add_interface: Called when a netdevice attached to the hardware is
  *      enabled. Because it is not called for monitor mode devices, @start
  *      and @stop must be implemented.
@@ -1831,6 +1843,10 @@ struct ieee80211_ops {
         void (*tx)(struct ieee80211_hw *hw, struct sk_buff *skb);
         int (*start)(struct ieee80211_hw *hw);
         void (*stop)(struct ieee80211_hw *hw);
+#ifdef CONFIG_PM
+        int (*suspend)(struct ieee80211_hw *hw, struct cfg80211_wowlan *wowlan);
+        int (*resume)(struct ieee80211_hw *hw);
+#endif
         int (*add_interface)(struct ieee80211_hw *hw,
                              struct ieee80211_vif *vif);
         int (*change_interface)(struct ieee80211_hw *hw,
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 321d598eb8cb..1ebc13383ae7 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1300,7 +1300,7 @@ static int ieee80211_set_channel(struct wiphy *wiphy,
 static int ieee80211_suspend(struct wiphy *wiphy,
                              struct cfg80211_wowlan *wowlan)
 {
-        return __ieee80211_suspend(wiphy_priv(wiphy));
+        return __ieee80211_suspend(wiphy_priv(wiphy), wowlan);
 }
 
 static int ieee80211_resume(struct wiphy *wiphy)
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index 0a602dbfdb2b..186e02f7cc32 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -135,7 +135,7 @@ static ssize_t reset_write(struct file *file, const char __user *user_buf,
         struct ieee80211_local *local = file->private_data;
 
         rtnl_lock();
-        __ieee80211_suspend(&local->hw);
+        __ieee80211_suspend(&local->hw, NULL);
         __ieee80211_resume(&local->hw);
         rtnl_unlock();
 
diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index 2ddb56e5b51f..aa16bd8ef789 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -41,6 +41,33 @@ static inline void drv_stop(struct ieee80211_local *local)
         local->started = false;
 }
 
+#ifdef CONFIG_PM
+static inline int drv_suspend(struct ieee80211_local *local,
+                              struct cfg80211_wowlan *wowlan)
+{
+        int ret;
+
+        might_sleep();
+
+        trace_drv_suspend(local);
+        ret = local->ops->suspend(&local->hw, wowlan);
+        trace_drv_return_int(local, ret);
+        return ret;
+}
+
+static inline int drv_resume(struct ieee80211_local *local)
+{
+        int ret;
+
+        might_sleep();
+
+        trace_drv_resume(local);
+        ret = local->ops->resume(&local->hw);
+        trace_drv_return_int(local, ret);
+        return ret;
+}
+#endif
+
 static inline int drv_add_interface(struct ieee80211_local *local,
                                     struct ieee80211_vif *vif)
 {
diff --git a/net/mac80211/driver-trace.h b/net/mac80211/driver-trace.h
index 191e834ec46b..11e1ea5111ea 100644
--- a/net/mac80211/driver-trace.h
+++ b/net/mac80211/driver-trace.h
@@ -108,6 +108,16 @@ DEFINE_EVENT(local_only_evt, drv_start,
         TP_ARGS(local)
 );
 
+DEFINE_EVENT(local_only_evt, drv_suspend,
+        TP_PROTO(struct ieee80211_local *local),
+        TP_ARGS(local)
+);
+
+DEFINE_EVENT(local_only_evt, drv_resume,
+        TP_PROTO(struct ieee80211_local *local),
+        TP_ARGS(local)
+);
+
 DEFINE_EVENT(local_only_evt, drv_stop,
         TP_PROTO(struct ieee80211_local *local),
         TP_ARGS(local)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 9e3b4f0f31bd..e89bc27f8dc3 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -764,6 +764,9 @@ struct ieee80211_local {
         /* device is started */
         bool started;
 
+        /* wowlan is enabled -- don't reconfig on resume */
+        bool wowlan;
+
         int tx_headroom; /* required headroom for hardware/radiotap */
 
         /* count for keys needing tailroom space allocation */
@@ -1250,7 +1253,8 @@ int ieee80211_reconfig(struct ieee80211_local *local);
 void ieee80211_stop_device(struct ieee80211_local *local);
 
 #ifdef CONFIG_PM
-int __ieee80211_suspend(struct ieee80211_hw *hw);
+int __ieee80211_suspend(struct ieee80211_hw *hw,
+                        struct cfg80211_wowlan *wowlan);
 
 static inline int __ieee80211_resume(struct ieee80211_hw *hw)
 {
@@ -1263,7 +1267,8 @@ static inline int __ieee80211_resume(struct ieee80211_hw *hw)
         return ieee80211_reconfig(hw_to_local(hw));
 }
 #else
-static inline int __ieee80211_suspend(struct ieee80211_hw *hw)
+static inline int __ieee80211_suspend(struct ieee80211_hw *hw,
+                                      struct cfg80211_wowlan *wowlan)
 {
         return 0;
 }
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index d8be1986a108..cb326d36be9c 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -696,6 +696,10 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
                 WLAN_CIPHER_SUITE_AES_CMAC
         };
 
+        if ((hw->wiphy->wowlan.flags || hw->wiphy->wowlan.n_patterns) &&
+            (!local->ops->suspend || !local->ops->resume))
+                return -EINVAL;
+
         if (hw->max_report_rates == 0)
                 hw->max_report_rates = hw->max_rates;
 
diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c
index 042461710880..730778a2c90c 100644
--- a/net/mac80211/pm.c
+++ b/net/mac80211/pm.c
@@ -6,7 +6,7 @@
 #include "driver-ops.h"
 #include "led.h"
 
-int __ieee80211_suspend(struct ieee80211_hw *hw)
+int __ieee80211_suspend(struct ieee80211_hw *hw, struct cfg80211_wowlan *wowlan)
 {
         struct ieee80211_local *local = hw_to_local(hw);
         struct ieee80211_sub_if_data *sdata;
@@ -47,6 +47,16 @@ int __ieee80211_suspend(struct ieee80211_hw *hw)
         cancel_work_sync(&local->dynamic_ps_enable_work);
         del_timer_sync(&local->dynamic_ps_timer);
 
+        local->wowlan = wowlan && local->open_count;
+        if (local->wowlan) {
+                int err = drv_suspend(local, wowlan);
+                if (err) {
+                        local->quiescing = false;
+                        return err;
+                }
+                goto suspend;
+        }
+
         /* disable keys */
         list_for_each_entry(sdata, &local->interfaces, list)
                 ieee80211_disable_keys(sdata);
@@ -104,6 +114,7 @@ int __ieee80211_suspend(struct ieee80211_hw *hw)
         if (local->open_count)
                 ieee80211_stop_device(local);
 
+ suspend:
         local->suspended = true;
         /* need suspended to be visible before quiescing is false */
         barrier();
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index ef0560a2346a..d3fe2d237485 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1125,9 +1125,27 @@ int ieee80211_reconfig(struct ieee80211_local *local)
         struct sta_info *sta;
         int res;
 
+#ifdef CONFIG_PM
         if (local->suspended)
                 local->resuming = true;
 
+        if (local->wowlan) {
+                local->wowlan = false;
+                res = drv_resume(local);
+                if (res < 0) {
+                        local->resuming = false;
+                        return res;
+                }
+                if (res == 0)
+                        goto wake_up;
+                WARN_ON(res > 1);
+                /*
+                 * res is 1, which means the driver requested
+                 * to go through a regular reset on wakeup.
+                 */
+        }
+#endif
+
         /* restart hardware */
         if (local->open_count) {
                 /*
@@ -1258,6 +1276,7 @@ int ieee80211_reconfig(struct ieee80211_local *local)
                 if (ieee80211_sdata_running(sdata))
                         ieee80211_enable_keys(sdata);
 
+ wake_up:
         ieee80211_wake_queues_by_reason(hw,
                         IEEE80211_QUEUE_STOP_REASON_SUSPEND);