mt76: mt7921: introduce schedule scan support

introduce schedule scan to control mt7921 firmware to do background scan in
defined plan to see if the matched SSID is available.
Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Co-developed-by: Soul Huang <Soul.Huang@mediatek.com>
Signed-off-by: Soul Huang <Soul.Huang@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7921/init.c

@@ -70,6 +70,11 @@ mt7921_init_wiphy(struct ieee80211_hw *hw)
 	wiphy->n_iface_combinations = ARRAY_SIZE(if_comb);
 	wiphy->max_scan_ie_len = MT7921_SCAN_IE_LEN;
 	wiphy->max_scan_ssids = 4;
+	wiphy->max_sched_scan_plan_interval = MT7921_MAX_SCHED_SCAN_INTERVAL;
+	wiphy->max_sched_scan_ie_len = IEEE80211_MAX_DATA_LEN;
+	wiphy->max_sched_scan_ssids = MT7921_MAX_SCHED_SCAN_SSID;
+	wiphy->max_match_sets = MT7921_MAX_SCAN_MATCH;
+	wiphy->max_sched_scan_reqs = 1;
 	wiphy->flags |= WIPHY_FLAG_HAS_CHANNEL_SWITCH;
 
 	wiphy_ext_feature_set(wiphy, NL80211_EXT_FEATURE_SET_SCAN_DWELL);

drivers/net/wireless/mediatek/mt76/mt7921/main.c

@@ -868,6 +868,42 @@ mt7921_cancel_hw_scan(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
 	mutex_unlock(&dev->mt76.mutex);
 }
 
+static int
+mt7921_start_sched_scan(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
+			struct cfg80211_sched_scan_request *req,
+			struct ieee80211_scan_ies *ies)
+{
+	struct mt7921_dev *dev = mt7921_hw_dev(hw);
+	struct mt76_phy *mphy = hw->priv;
+	int err;
+
+	mutex_lock(&dev->mt76.mutex);
+
+	err = mt7921_mcu_sched_scan_req(mphy->priv, vif, req);
+	if (err < 0)
+		goto out;
+
+	err = mt7921_mcu_sched_scan_enable(mphy->priv, vif, true);
+out:
+	mutex_unlock(&dev->mt76.mutex);
+
+	return err;
+}
+
+static int
+mt7921_stop_sched_scan(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
+{
+	struct mt7921_dev *dev = mt7921_hw_dev(hw);
+	struct mt76_phy *mphy = hw->priv;
+	int err;
+
+	mutex_lock(&dev->mt76.mutex);
+	err = mt7921_mcu_sched_scan_enable(mphy->priv, vif, false);
+	mutex_unlock(&dev->mt76.mutex);
+
+	return err;
+}
+
 static int
 mt7921_set_antenna(struct ieee80211_hw *hw, u32 tx_ant, u32 rx_ant)
 {
@@ -957,4 +993,6 @@ const struct ieee80211_ops mt7921_ops = {
 	.hw_scan = mt7921_hw_scan,
 	.cancel_hw_scan = mt7921_cancel_hw_scan,
 	.sta_statistics = mt7921_sta_statistics,
+	.sched_scan_start = mt7921_start_sched_scan,
+	.sched_scan_stop = mt7921_stop_sched_scan,
 };

drivers/net/wireless/mediatek/mt76/mt7921/mcu.c

@@ -2361,6 +2361,89 @@ int mt7921_mcu_cancel_hw_scan(struct mt7921_phy *phy,
 				 sizeof(req), false);
 }
 
+int mt7921_mcu_sched_scan_req(struct mt7921_phy *phy,
+			      struct ieee80211_vif *vif,
+			      struct cfg80211_sched_scan_request *sreq)
+{
+	struct mt7921_vif *mvif = (struct mt7921_vif *)vif->drv_priv;
+	struct ieee80211_channel **scan_list = sreq->channels;
+	struct mt7921_dev *dev = phy->dev;
+	struct mt7921_mcu_scan_channel *chan;
+	struct mt7921_sched_scan_req *req;
+	struct cfg80211_match_set *match;
+	struct cfg80211_ssid *ssid;
+	struct sk_buff *skb;
+	int i;
+
+	skb = mt76_mcu_msg_alloc(&dev->mt76, NULL,
+				 sizeof(*req) + sreq->ie_len);
+	if (!skb)
+		return -ENOMEM;
+
+	mvif->mt76.scan_seq_num = (mvif->mt76.scan_seq_num + 1) & 0x7f;
+
+	req = (struct mt7921_sched_scan_req *)skb_put(skb, sizeof(*req));
+	req->version = 1;
+	req->seq_num = mvif->mt76.scan_seq_num;
+
+	req->ssids_num = sreq->n_ssids;
+	for (i = 0; i < req->ssids_num; i++) {
+		ssid = &sreq->ssids[i];
+		memcpy(req->ssids[i].ssid, ssid->ssid, ssid->ssid_len);
+		req->ssids[i].ssid_len = cpu_to_le32(ssid->ssid_len);
+	}
+
+	req->match_num = sreq->n_match_sets;
+	for (i = 0; i < req->match_num; i++) {
+		match = &sreq->match_sets[i];
+		memcpy(req->match[i].ssid, match->ssid.ssid,
+		       match->ssid.ssid_len);
+		req->match[i].rssi_th = cpu_to_le32(match->rssi_thold);
+		req->match[i].ssid_len = match->ssid.ssid_len;
+	}
+
+	req->channel_type = sreq->n_channels ? 4 : 0;
+	req->channels_num = min_t(u8, sreq->n_channels, 64);
+	for (i = 0; i < req->channels_num; i++) {
+		chan = &req->channels[i];
+		chan->band = scan_list[i]->band == NL80211_BAND_2GHZ ? 1 : 2;
+		chan->channel_num = scan_list[i]->hw_value;
+	}
+
+	req->intervals_num = sreq->n_scan_plans;
+	for (i = 0; i < req->intervals_num; i++)
+		req->intervals[i] = cpu_to_le16(sreq->scan_plans[i].interval);
+
+	if (sreq->ie_len > 0) {
+		req->ie_len = cpu_to_le16(sreq->ie_len);
+		memcpy(skb_put(skb, sreq->ie_len), sreq->ie, sreq->ie_len);
+	}
+
+	return mt76_mcu_skb_send_msg(&dev->mt76, skb, MCU_CMD_SCHED_SCAN_REQ,
+				     false);
+}
+
+int mt7921_mcu_sched_scan_enable(struct mt7921_phy *phy,
+				 struct ieee80211_vif *vif,
+				 bool enable)
+{
+	struct mt7921_dev *dev = phy->dev;
+	struct {
+		u8 active; /* 0: enabled 1: disabled */
+		u8 rsv[3];
+	} __packed req = {
+		.active = !enable,
+	};
+
+	if (enable)
+		set_bit(MT76_HW_SCHED_SCANNING, &phy->mt76->state);
+	else
+		clear_bit(MT76_HW_SCHED_SCANNING, &phy->mt76->state);
+
+	return mt76_mcu_send_msg(&dev->mt76, MCU_CMD_SCHED_SCAN_ENABLE, &req,
+				 sizeof(req), false);
+}
+
 u32 mt7921_get_wtbl_info(struct mt7921_dev *dev, u16 wlan_idx)
 {
 	struct mt7921_mcu_wlan_info wtbl_info = {

drivers/net/wireless/mediatek/mt76/mt7921/mcu.h

@@ -879,6 +879,26 @@ struct mt7921_hw_scan_done {
 	__le32 beacon_5g_num;
 } __packed;
 
+struct mt7921_sched_scan_req {
+	u8 version;
+	u8 seq_num;
+	u8 stop_on_match;
+	u8 ssids_num;
+	u8 match_num;
+	u8 pad;
+	__le16 ie_len;
+	struct mt7921_mcu_scan_ssid ssids[MT7921_MAX_SCHED_SCAN_SSID];
+	struct mt7921_mcu_scan_match match[MT7921_MAX_SCAN_MATCH];
+	u8 channel_type;
+	u8 channels_num;
+	u8 intervals_num;
+	u8 scan_func;
+	struct mt7921_mcu_scan_channel channels[64];
+	__le16 intervals[MT7921_MAX_SCHED_SCAN_INTERVAL];
+	u8 bss_idx;
+	u8 pad2[64];
+} __packed;
+
 struct mt7921_mcu_bss_event {
 	u8 bss_idx;
 	u8 is_absent;

drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h

@@ -44,6 +44,9 @@
 #define MT7921_SKU_TABLE_SIZE		(MT7921_SKU_RATE_NUM + 1)
 
 #define MT7921_SCAN_IE_LEN		600
+#define MT7921_MAX_SCHED_SCAN_INTERVAL	10
+#define MT7921_MAX_SCHED_SCAN_SSID	10
+#define MT7921_MAX_SCAN_MATCH		16
 
 struct mt7921_vif;
 struct mt7921_sta;
@@ -343,6 +346,12 @@ void mt7921_scan_work(struct work_struct *work);
 int mt7921_mcu_set_channel_domain(struct mt7921_phy *phy);
 int mt7921_mcu_hw_scan(struct mt7921_phy *phy, struct ieee80211_vif *vif,
 		       struct ieee80211_scan_request *scan_req);
+int mt7921_mcu_sched_scan_req(struct mt7921_phy *phy,
+			      struct ieee80211_vif *vif,
+			      struct cfg80211_sched_scan_request *sreq);
+int mt7921_mcu_sched_scan_enable(struct mt7921_phy *phy,
+				 struct ieee80211_vif *vif,
+				 bool enable);
 int mt7921_mcu_cancel_hw_scan(struct mt7921_phy *phy,
 			      struct ieee80211_vif *vif);
 u32 mt7921_get_wtbl_info(struct mt7921_dev *dev, u16 wlan_idx);