nl80211: add power save commands

The most needed command from nl80211, which Wireless Extensions had,
is support for power save mode. Add a simple command to make it possible
to enable and disable power save via nl80211.

I was also planning about extending the interface, for example adding the
timeout value, but after thinking more about this I decided not to do it.
Basically there were three reasons:

Firstly, the parameters for power save are very much hardware dependent.
Trying to find a unified interface which would work with all hardware, and
still make sense to users, will be very difficult.

Secondly, IEEE 802.11 power save implementation in Linux is still in state
of flux. We have a long way to still to go and there is no way to predict
what kind of implementation we will have after few years. And because we
need to support nl80211 interface a long time, practically forever, adding
now parameters to nl80211 might create maintenance problems later on.

Third issue are the users. Power save parameters are mostly used for
debugging, so debugfs is better, more flexible, interface for this.
For example, wpa_supplicant currently doesn't configure anything related
to power save mode. It's better to strive that kernel can automatically
optimise the power save parameters, like with help of pm qos network
and other traffic parameters.

Later on, when we have better understanding of power save, we can extend
this command with more features, if there's a need for that.

Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 14 insertions, 3 deletions

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index 8e6384f..28ba20f 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -416,6 +416,9 @@ enum nl80211_commands {
 	NL80211_CMD_ACTION,
 	NL80211_CMD_ACTION_TX_STATUS,
 
+	NL80211_CMD_SET_POWER_SAVE,
+	NL80211_CMD_GET_POWER_SAVE,
+
 	/* add new commands above here */
 
 	/* used to define NL80211_CMD_MAX below */
@@ -837,6 +840,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_ACK,
 
+	NL80211_ATTR_PS_STATE,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -1573,4 +1578,9 @@ enum nl80211_band {
 	NL80211_BAND_5GHZ,
 };
 
+enum nl80211_ps_state {
+	NL80211_PS_DISABLED,
+	NL80211_PS_ENABLED,
+};
+
 #endif /* __LINUX_NL80211_H */
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 7188934..3d134a1 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1150,7 +1150,6 @@ struct cfg80211_ops {
 			  enum nl80211_channel_type channel_type,
 			  const u8 *buf, size_t len, u64 *cookie);
 
-	/* some temporary stuff to finish wext */
 	int	(*set_power_mgmt)(struct wiphy *wiphy, struct net_device *dev,
 				  bool enabled, int timeout);
 };
@@ -1489,6 +1488,9 @@ struct wireless_dev {
 	struct cfg80211_internal_bss *auth_bsses[MAX_AUTH_BSSES];
 	struct cfg80211_internal_bss *current_bss; /* associated / joined */
 
+	bool ps;
+	int ps_timeout;
+
 #ifdef CONFIG_CFG80211_WEXT
 	/* wext data */
 	struct {
@@ -1500,8 +1502,7 @@ struct wireless_dev {
 		u8 bssid[ETH_ALEN], prev_bssid[ETH_ALEN];
 		u8 ssid[IEEE80211_MAX_SSID_LEN];
 		s8 default_key, default_mgmt_key;
-		bool ps, prev_bssid_valid;
-		int ps_timeout;
+		bool prev_bssid_valid;
 	} wext;
 #endif
 };