// SPDX-License-Identifier: BSD-3-Clause-Clear
/*
 * Copyright (C) 2024 Felix Fietkau <nbd@nbd.name>
 */
#include "mt76.h"

static void mt76_scan_complete(struct mt76_dev *dev, bool abort)
{
        struct mt76_phy *phy = dev->scan.phy;
        struct cfg80211_scan_info info = {
                .aborted = abort,
        };

        if (!phy)
                return;

        clear_bit(MT76_SCANNING, &phy->state);

        if (dev->scan.chan && phy->main_chandef.chan &&
            !test_bit(MT76_MCU_RESET, &dev->phy.state))
                mt76_set_channel(phy, &phy->main_chandef, false);
        mt76_put_vif_phy_link(phy, dev->scan.vif, dev->scan.mlink);
        memset(&dev->scan, 0, sizeof(dev->scan));
        if (!test_bit(MT76_MCU_RESET, &dev->phy.state))
                ieee80211_scan_completed(phy->hw, &info);
}

void mt76_abort_scan(struct mt76_dev *dev)
{
        cancel_delayed_work_sync(&dev->scan_work);
        mt76_scan_complete(dev, true);
}
EXPORT_SYMBOL_GPL(mt76_abort_scan);

static void
mt76_scan_send_probe(struct mt76_dev *dev, struct cfg80211_ssid *ssid)
{
        struct cfg80211_scan_request *req = dev->scan.req;
        struct ieee80211_vif *vif = dev->scan.vif;
        struct mt76_vif_link *mvif = dev->scan.mlink;
        enum nl80211_band band = dev->scan.chan->band;
        struct mt76_phy *phy = dev->scan.phy;
        struct ieee80211_tx_info *info;
        struct sk_buff *skb;

        skb = ieee80211_probereq_get(phy->hw, vif->addr, ssid->ssid,
                                     ssid->ssid_len, req->ie_len);
        if (!skb)
                return;

        if (is_unicast_ether_addr(req->bssid)) {
                struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;

                ether_addr_copy(hdr->addr1, req->bssid);
                ether_addr_copy(hdr->addr3, req->bssid);
        }

        if (req->ie_len)
                skb_put_data(skb, req->ie, req->ie_len);

        skb->priority = 7;
        skb_set_queue_mapping(skb, IEEE80211_AC_VO);

        rcu_read_lock();

        if (!ieee80211_tx_prepare_skb(phy->hw, vif, skb, band, NULL))
                goto out;

        info = IEEE80211_SKB_CB(skb);
        if (req->no_cck)
                info->flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
        info->control.flags |= IEEE80211_TX_CTRL_DONT_USE_RATE_MASK;

        mt76_tx(phy, NULL, mvif->wcid, skb);

out:
        rcu_read_unlock();
}

void mt76_scan_work(struct work_struct *work)
{
        struct mt76_dev *dev = container_of(work, struct mt76_dev,
                                            scan_work.work);
        struct cfg80211_scan_request *req = dev->scan.req;
        struct cfg80211_chan_def chandef = {};
        struct mt76_phy *phy = dev->scan.phy;
        int duration = HZ / 9; /* ~110 ms */
        int i;

        if (dev->scan.chan_idx >= req->n_channels) {
                mt76_scan_complete(dev, false);
                return;
        }

        if (dev->scan.chan && phy->num_sta) {
                dev->scan.chan = NULL;
                mt76_set_channel(phy, &phy->main_chandef, false);
                goto out;
        }

        dev->scan.chan = req->channels[dev->scan.chan_idx++];
        cfg80211_chandef_create(&chandef, dev->scan.chan, NL80211_CHAN_HT20);
        mt76_set_channel(phy, &chandef, true);

        if (!req->n_ssids ||
            chandef.chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
                goto out;

        duration = HZ / 16; /* ~60 ms */
        local_bh_disable();
        for (i = 0; i < req->n_ssids; i++)
                mt76_scan_send_probe(dev, &req->ssids[i]);
        local_bh_enable();

out:
        if (dev->scan.chan)
                duration = max_t(int, duration,
                                 msecs_to_jiffies(req->duration +
                                                  (req->duration >> 5)));

        ieee80211_queue_delayed_work(dev->phy.hw, &dev->scan_work, duration);
}

int mt76_hw_scan(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                 struct ieee80211_scan_request *req)
{
        struct mt76_phy *phy = hw->priv;
        struct mt76_dev *dev = phy->dev;
        struct mt76_vif_link *mlink;
        int ret = 0;

        if (hw->wiphy->n_radio > 1) {
                phy = dev->band_phys[req->req.channels[0]->band];
                if (!phy)
                        return -EINVAL;
        }

        mutex_lock(&dev->mutex);

        if (dev->scan.req || phy->roc_vif ||
            test_bit(MT76_MCU_RESET, &dev->phy.state)) {
                ret = -EBUSY;
                goto out;
        }

        mlink = mt76_get_vif_phy_link(phy, vif);
        if (IS_ERR(mlink)) {
                ret = PTR_ERR(mlink);
                goto out;
        }

        memset(&dev->scan, 0, sizeof(dev->scan));
        dev->scan.req = &req->req;
        dev->scan.vif = vif;
        dev->scan.phy = phy;
        dev->scan.mlink = mlink;
        ieee80211_queue_delayed_work(dev->phy.hw, &dev->scan_work, 0);

out:
        mutex_unlock(&dev->mutex);

        return ret;
}
EXPORT_SYMBOL_GPL(mt76_hw_scan);

void mt76_cancel_hw_scan(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
{
        struct mt76_phy *phy = hw->priv;

        mt76_abort_scan(phy->dev);
}
EXPORT_SYMBOL_GPL(mt76_cancel_hw_scan);