wifi: mt76: fix multi-radio on-channel scanning

avoid unnecessary channel switch when performing an on-channel scan
using a multi-radio device.

Fixes: c56d6edebc1f ("wifi: mt76: mt7996: use emulated hardware scan support")
Signed-off-by: Chad Monroe <chad@monroe.io>
Link: https://patch.msgid.link/20251118102723.47997-1-nbd@nbd.name
Link: https://patch.msgid.link/20260309060730.87840-1-nbd@nbd.name
Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/drivers/net/wireless/mediatek/mt76/scan.c b/drivers/net/wireless/mediatek/mt76/scan.c
index ff9176cdee3dee2b97f281a942cb91a631c24bcf..89f16c23e352fc5b90692a3dc4dbd394be864f24 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/scan.c
+++ b/drivers/net/wireless/mediatek/mt76/scan.c
@@ -16,7 +16,7 @@ static void mt76_scan_complete(struct mt76_dev *dev, bool abort)
 
        clear_bit(MT76_SCANNING, &phy->state);
 
-       if (dev->scan.chan && phy->main_chandef.chan &&
+       if (dev->scan.chan && phy->main_chandef.chan && phy->offchannel &&
            !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);
@@ -87,6 +87,7 @@ void mt76_scan_work(struct work_struct *work)
        struct cfg80211_chan_def chandef = {};
        struct mt76_phy *phy = dev->scan.phy;
        int duration = HZ / 9; /* ~110 ms */
+       bool offchannel = true;
        int i;
 
        if (dev->scan.chan_idx >= req->n_channels) {
@@ -94,7 +95,7 @@ void mt76_scan_work(struct work_struct *work)
                return;
        }
 
-       if (dev->scan.chan && phy->num_sta) {
+       if (dev->scan.chan && phy->num_sta && phy->offchannel) {
                dev->scan.chan = NULL;
                mt76_set_channel(phy, &phy->main_chandef, false);
                goto out;
@@ -102,20 +103,26 @@ void mt76_scan_work(struct work_struct *work)
 
        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 (phy->main_chandef.chan == dev->scan.chan) {
+               chandef = phy->main_chandef;
+               offchannel = false;
+       }
+
+       mt76_set_channel(phy, &chandef, offchannel);
 
        if (!req->n_ssids ||
            chandef.chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
                goto out;
 
-       duration = HZ / 16; /* ~60 ms */
+       if (phy->offchannel)
+               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)
+       if (dev->scan.chan && phy->offchannel)
                duration = max_t(int, duration,
                                 msecs_to_jiffies(req->duration +
                                                  (req->duration >> 5)));