mt76: mt7603: introduce SAR support

Add SAR spec support to mt7603 driver to allow configuring SAR power
limitations on the frequency ranges from the userland.
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7603/main.c

@@ -133,13 +133,15 @@ void mt7603_init_edcca(struct mt7603_dev *dev)
 }
 
 static int
-mt7603_set_channel(struct mt7603_dev *dev, struct cfg80211_chan_def *def)
+mt7603_set_channel(struct ieee80211_hw *hw, struct cfg80211_chan_def *def)
 {
+	struct mt7603_dev *dev = hw->priv;
 	u8 *rssi_data = (u8 *)dev->mt76.eeprom.data;
 	int idx, ret;
 	u8 bw = MT_BW_20;
 	bool failed = false;
 
+	ieee80211_stop_queues(hw);
 	cancel_delayed_work_sync(&dev->mphy.mac_work);
 	tasklet_disable(&dev->mt76.pre_tbtt_tasklet);
 
@@ -205,9 +207,28 @@ mt7603_set_channel(struct mt7603_dev *dev, struct cfg80211_chan_def *def)
 	if (failed)
 		mt7603_mac_work(&dev->mphy.mac_work.work);
 
+	ieee80211_wake_queues(hw);
+
 	return ret;
 }
 
+static int mt7603_set_sar_specs(struct ieee80211_hw *hw,
+				const struct cfg80211_sar_specs *sar)
+{
+	struct mt7603_dev *dev = hw->priv;
+	struct mt76_phy *mphy = &dev->mphy;
+	int err;
+
+	if (!cfg80211_chandef_valid(&mphy->chandef))
+		return -EINVAL;
+
+	err = mt76_init_sar_power(hw, sar);
+	if (err)
+		return err;
+
+	return mt7603_set_channel(hw, &mphy->chandef);
+}
+
 static int
 mt7603_config(struct ieee80211_hw *hw, u32 changed)
 {
@@ -215,11 +236,8 @@ mt7603_config(struct ieee80211_hw *hw, u32 changed)
 	int ret = 0;
 
 	if (changed & (IEEE80211_CONF_CHANGE_CHANNEL |
-		       IEEE80211_CONF_CHANGE_POWER)) {
-		ieee80211_stop_queues(hw);
-		ret = mt7603_set_channel(dev, &hw->conf.chandef);
-		ieee80211_wake_queues(hw);
-	}
+		       IEEE80211_CONF_CHANGE_POWER))
+		ret = mt7603_set_channel(hw, &hw->conf.chandef);
 
 	if (changed & IEEE80211_CONF_CHANGE_MONITOR) {
 		mutex_lock(&dev->mt76.mutex);
@@ -700,6 +718,7 @@ const struct ieee80211_ops mt7603_ops = {
 	.set_tim = mt76_set_tim,
 	.get_survey = mt76_get_survey,
 	.get_antenna = mt76_get_antenna,
+	.set_sar_specs = mt7603_set_sar_specs,
 };
 
 MODULE_LICENSE("Dual BSD/GPL");

drivers/net/wireless/mediatek/mt76/mt7603/mcu.c

@@ -403,7 +403,7 @@ int mt7603_mcu_set_channel(struct mt7603_dev *dev)
 		.tx_streams = n_chains,
 		.rx_streams = n_chains,
 	};
-	s8 tx_power;
+	s8 tx_power = hw->conf.power_level * 2;
 	int i, ret;
 
 	if (dev->mphy.chandef.width == NL80211_CHAN_WIDTH_40) {
@@ -414,7 +414,7 @@ int mt7603_mcu_set_channel(struct mt7603_dev *dev)
 			req.center_chan -= 2;
 	}
 
-	tx_power = hw->conf.power_level * 2;
+	tx_power = mt76_get_sar_power(&dev->mphy, chandef->chan, tx_power);
 	if (dev->mphy.antenna_mask == 3)
 		tx_power -= 6;
 	tx_power = min(tx_power, dev->tx_power_limit);