cfg80211: move txpower wext from mac80211

This patch introduces new cfg80211 API to set the TX power
via cfg80211, puts the wext code into cfg80211 and updates
mac80211 to use all that. The -ENETDOWN bits are a hack but
will go away soon.

Signed-off-by: Johannes Berg <[e-mail]>
Signed-off-by: John W. Linville <[e-mail]>

include/net/cfg80211.h

···
 };
 
 /**
+ * enum tx_power_setting - TX power adjustment
+ *
+ * @TX_POWER_AUTOMATIC: the dbm parameter is ignored
+ * @TX_POWER_LIMITED: limit TX power by the dbm parameter
+ * @TX_POWER_FIXED: fix TX power to the dbm parameter
+ * @TX_POWER_OFF: turn off completely (will go away)
+ */
+enum tx_power_setting {
+	TX_POWER_AUTOMATIC,
+	TX_POWER_LIMITED,
+	TX_POWER_FIXED,
+	TX_POWER_OFF,
+};
+
+/**
  * struct cfg80211_ops - backend description for wireless configuration
  *
  * This struct is registered by fullmac card drivers and/or wireless stacks
···
  *	@changed bitfield (see &enum wiphy_params_flags) describes which values
  *	have changed. The actual parameter values are available in
  *	struct wiphy. If returning an error, no value should be changed.
+ *
+ * @set_tx_power: set the transmit power according to the parameters
+ * @get_tx_power: store the current TX power into the dbm variable;
+ *	return 0 if successful; or -ENETDOWN if successful but power
+ *	is disabled (this will go away)
  */
 struct cfg80211_ops {
 	int	(*suspend)(struct wiphy *wiphy);
···
 	int	(*leave_ibss)(struct wiphy *wiphy, struct net_device *dev);
 
 	int	(*set_wiphy_params)(struct wiphy *wiphy, u32 changed);
+
+	int	(*set_tx_power)(struct wiphy *wiphy,
+				enum tx_power_setting type, int dbm);
+	int	(*get_tx_power)(struct wiphy *wiphy, int *dbm);
 };
 
 /*
···
 int cfg80211_wext_giwencode(struct net_device *dev,
 			    struct iw_request_info *info,
 			    struct iw_point *erq, char *keybuf);
+int cfg80211_wext_siwtxpower(struct net_device *dev,
+			     struct iw_request_info *info,
+			     union iwreq_data *data, char *keybuf);
+int cfg80211_wext_giwtxpower(struct net_device *dev,
+			     struct iw_request_info *info,
+			     union iwreq_data *data, char *keybuf);
 
 /*
  * callbacks for asynchronous cfg80211 methods, notification

net/mac80211/cfg.c

···
 	return 0;
 }
 
+static int ieee80211_set_tx_power(struct wiphy *wiphy,
+				  enum tx_power_setting type, int dbm)
+{
+	struct ieee80211_local *local = wiphy_priv(wiphy);
+	struct ieee80211_channel *chan = local->hw.conf.channel;
+	u32 changes = 0;
+	bool radio_enabled = true;
+
+	switch (type) {
+	case TX_POWER_AUTOMATIC:
+		local->user_power_level = -1;
+		break;
+	case TX_POWER_LIMITED:
+		if (dbm < 0)
+			return -EINVAL;
+		local->user_power_level = dbm;
+		break;
+	case TX_POWER_FIXED:
+		if (dbm < 0)
+			return -EINVAL;
+		/* TODO: move to cfg80211 when it knows the channel */
+		if (dbm > chan->max_power)
+			return -EINVAL;
+		local->user_power_level = dbm;
+		break;
+	case TX_POWER_OFF:
+		radio_enabled = false;
+		break;
+	}
+
+	if (radio_enabled != local->hw.conf.radio_enabled) {
+		changes |= IEEE80211_CONF_CHANGE_RADIO_ENABLED;
+		local->hw.conf.radio_enabled = radio_enabled;
+	}
+
+	ieee80211_hw_config(local, changes);
+
+	return 0;
+}
+
+static int ieee80211_get_tx_power(struct wiphy *wiphy, int *dbm)
+{
+	struct ieee80211_local *local = wiphy_priv(wiphy);
+
+	*dbm = local->hw.conf.power_level;
+
+	if (!local->hw.conf.radio_enabled)
+		return -ENETDOWN;
+
+	return 0;
+}
+
 struct cfg80211_ops mac80211_config_ops = {
 	.add_virtual_intf = ieee80211_add_iface,
 	.del_virtual_intf = ieee80211_del_iface,
···
 	.join_ibss = ieee80211_join_ibss,
 	.leave_ibss = ieee80211_leave_ibss,
 	.set_wiphy_params = ieee80211_set_wiphy_params,
+	.set_tx_power = ieee80211_set_tx_power,
+	.get_tx_power = ieee80211_get_tx_power,
 };

net/mac80211/wext.c

···
 	return 0;
 }
 
-static int ieee80211_ioctl_siwtxpower(struct net_device *dev,
-				      struct iw_request_info *info,
-				      union iwreq_data *data, char *extra)
-{
-	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
-	struct ieee80211_channel* chan = local->hw.conf.channel;
-	bool reconf = false;
-	u32 reconf_flags = 0;
-	int new_power_level;
-
-	if ((data->txpower.flags & IW_TXPOW_TYPE) != IW_TXPOW_DBM)
-		return -EINVAL;
-	if (data->txpower.flags & IW_TXPOW_RANGE)
-		return -EINVAL;
-	if (!chan)
-		return -EINVAL;
-
-	/* only change when not disabling */
-	if (!data->txpower.disabled) {
-		if (data->txpower.fixed) {
-			if (data->txpower.value < 0)
-				return -EINVAL;
-			new_power_level = data->txpower.value;
-			/*
-			 * Debatable, but we cannot do a fixed power
-			 * level above the regulatory constraint.
-			 * Use "iwconfig wlan0 txpower 15dBm" instead.
-			 */
-			if (new_power_level > chan->max_power)
-				return -EINVAL;
-		} else {
-			/*
-			 * Automatic power level setting, max being the value
-			 * passed in from userland.
-			 */
-			if (data->txpower.value < 0)
-				new_power_level = -1;
-			else
-				new_power_level = data->txpower.value;
-		}
-
-		reconf = true;
-
-		/*
-		 * ieee80211_hw_config() will limit to the channel's
-		 * max power and possibly power constraint from AP.
-		 */
-		local->user_power_level = new_power_level;
-	}
-
-	if (local->hw.conf.radio_enabled != !(data->txpower.disabled)) {
-		local->hw.conf.radio_enabled = !(data->txpower.disabled);
-		reconf_flags |= IEEE80211_CONF_CHANGE_RADIO_ENABLED;
-		ieee80211_led_radio(local, local->hw.conf.radio_enabled);
-	}
-
-	if (reconf || reconf_flags)
-		ieee80211_hw_config(local, reconf_flags);
-
-	return 0;
-}
-
-static int ieee80211_ioctl_giwtxpower(struct net_device *dev,
-				   struct iw_request_info *info,
-				   union iwreq_data *data, char *extra)
-{
-	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
-
-	data->txpower.fixed = 1;
-	data->txpower.disabled = !(local->hw.conf.radio_enabled);
-	data->txpower.value = local->hw.conf.power_level;
-	data->txpower.flags = IW_TXPOW_DBM;
-
-	return 0;
-}
-
 static int ieee80211_ioctl_siwpower(struct net_device *dev,
 				    struct iw_request_info *info,
 				    struct iw_param *wrq,
···
 	(iw_handler) cfg80211_wext_giwrts,		/* SIOCGIWRTS */
 	(iw_handler) cfg80211_wext_siwfrag,		/* SIOCSIWFRAG */
 	(iw_handler) cfg80211_wext_giwfrag,		/* SIOCGIWFRAG */
-	(iw_handler) ieee80211_ioctl_siwtxpower,	/* SIOCSIWTXPOW */
-	(iw_handler) ieee80211_ioctl_giwtxpower,	/* SIOCGIWTXPOW */
+	(iw_handler) cfg80211_wext_siwtxpower,		/* SIOCSIWTXPOW */
+	(iw_handler) cfg80211_wext_giwtxpower,		/* SIOCGIWTXPOW */
 	(iw_handler) cfg80211_wext_siwretry,		/* SIOCSIWRETRY */
 	(iw_handler) cfg80211_wext_giwretry,		/* SIOCGIWRETRY */
 	(iw_handler) cfg80211_wext_siwencode,		/* SIOCSIWENCODE */

net/wireless/wext-compat.c

···
 	return err;
 }
 EXPORT_SYMBOL_GPL(cfg80211_wext_giwencode);
+
+int cfg80211_wext_siwtxpower(struct net_device *dev,
+			     struct iw_request_info *info,
+			     union iwreq_data *data, char *extra)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
+	enum tx_power_setting type;
+	int dbm = 0;
+
+	if ((data->txpower.flags & IW_TXPOW_TYPE) != IW_TXPOW_DBM)
+		return -EINVAL;
+	if (data->txpower.flags & IW_TXPOW_RANGE)
+		return -EINVAL;
+
+	if (!rdev->ops->set_tx_power)
+		return -EOPNOTSUPP;
+
+	/* only change when not disabling */
+	if (!data->txpower.disabled) {
+		if (data->txpower.fixed) {
+			/*
+			 * wext doesn't support negative values, see
+			 * below where it's for automatic
+			 */
+			if (data->txpower.value < 0)
+				return -EINVAL;
+			dbm = data->txpower.value;
+			type = TX_POWER_FIXED;
+			/* TODO: do regulatory check! */
+		} else {
+			/*
+			 * Automatic power level setting, max being the value
+			 * passed in from userland.
+			 */
+			if (data->txpower.value < 0) {
+				type = TX_POWER_AUTOMATIC;
+			} else {
+				dbm = data->txpower.value;
+				type = TX_POWER_LIMITED;
+			}
+		}
+	} else {
+		type = TX_POWER_OFF;
+	}
+
+	return rdev->ops->set_tx_power(wdev->wiphy, type, dbm);;
+}
+EXPORT_SYMBOL_GPL(cfg80211_wext_siwtxpower);
+
+int cfg80211_wext_giwtxpower(struct net_device *dev,
+			     struct iw_request_info *info,
+			     union iwreq_data *data, char *extra)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
+	int err, val;
+
+	if ((data->txpower.flags & IW_TXPOW_TYPE) != IW_TXPOW_DBM)
+		return -EINVAL;
+	if (data->txpower.flags & IW_TXPOW_RANGE)
+		return -EINVAL;
+
+	if (!rdev->ops->get_tx_power)
+		return -EOPNOTSUPP;
+
+	err = rdev->ops->get_tx_power(wdev->wiphy, &val);
+	/* HACK!!! */
+	if (err && err != -ENETDOWN)
+		return err;
+
+	/* well... oh well */
+	data->txpower.fixed = 1;
+	data->txpower.disabled = err == -ENETDOWN;
+	data->txpower.value = val;
+	data->txpower.flags = IW_TXPOW_DBM;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cfg80211_wext_giwtxpower);