[PATCH v2 3/3] wifi: mt76: mt792x: report txpower for the requested vif link

Sean Wang
2026-04-01T18:23:41Z

mt792x currently reports txpower from the generic PHY cached state,
which may not match the requested vif/link context.

Resolve the requested link channel and derive txpower from that channel
instead, with fallback to the current PHY chandef if no valid chanctx is
available.

Reported-by: Devin Wittmayer <lucid_duck@justthetip.ca>
Closes: https://lore.kernel.org/linux-wireless/20260130215839.53270-1-lucid_duck@justthetip.ca/
Tested-by: Devin Wittmayer <lucid_duck@justthetip.ca>
Tested-by: Satadru Pramanik <satadru@gmail.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
---
v2:
- Rebased onto the latest mt76 tree
- Added Reported-by, Tested-by, Co-developed-by and Signed-off-by tags
---
.../net/wireless/mediatek/mt76/mt7921/main.c | 2 +-
.../net/wireless/mediatek/mt76/mt7925/main.c | 2 +-
drivers/net/wireless/mediatek/mt76/mt792x.h | 2 +
.../net/wireless/mediatek/mt76/mt792x_core.c | 41 +++++++++++++++++++
4 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/main.c b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
index 3d74fabe7408..2e7cdf8edc12 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
@@ -1552,7 +1552,7 @@ const struct ieee80211_ops mt7921_ops = {
.wake_tx_queue = mt76_wake_tx_queue,
.release_buffered_frames = mt76_release_buffered_frames,
.channel_switch_beacon = mt7921_channel_switch_beacon,
- .get_txpower = mt76_get_txpower,
+ .get_txpower = mt792x_get_txpower,
.get_stats = mt792x_get_stats,
.get_et_sset_count = mt792x_get_et_sset_count,
.get_et_strings = mt792x_get_et_strings,
diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/main.c b/drivers/net/wireless/mediatek/mt76/mt7925/main.c
index 73d3722739d0..53e1a93c6976 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7925/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7925/main.c
@@ -2433,7 +2433,7 @@ const struct ieee80211_ops mt7925_ops = {
.wake_tx_queue = mt76_wake_tx_queue,
.release_buffered_frames = mt76_release_buffered_frames,
.channel_switch_beacon = mt7925_channel_switch_beacon,
- .get_txpower = mt76_get_txpower,
+ .get_txpower = mt792x_get_txpower,
.get_stats = mt792x_get_stats,
.get_et_sset_count = mt792x_get_et_sset_count,
.get_et_strings = mt792x_get_et_strings,
diff --git a/drivers/net/wireless/mediatek/mt76/mt792x.h b/drivers/net/wireless/mediatek/mt76/mt792x.h
index 4ff93f2cd624..65eba18bc3a1 100644
--- a/drivers/net/wireless/mediatek/mt76/mt792x.h
+++ b/drivers/net/wireless/mediatek/mt76/mt792x.h
@@ -397,6 +397,8 @@ void mt792x_roc_timer(struct timer_list *timer);
void mt792x_csa_timer(struct timer_list *timer);
void mt792x_flush(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
u32 queues, bool drop);
+int mt792x_get_txpower(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
+ unsigned int link_id, int *dbm);
int mt792x_assign_vif_chanctx(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
struct ieee80211_bss_conf *link_conf,
diff --git a/drivers/net/wireless/mediatek/mt76/mt792x_core.c b/drivers/net/wireless/mediatek/mt76/mt792x_core.c
index 152cfcca2f90..3fd1be7db1f4 100644
--- a/drivers/net/wireless/mediatek/mt76/mt792x_core.c
+++ b/drivers/net/wireless/mediatek/mt76/mt792x_core.c
@@ -329,6 +329,47 @@ void mt792x_flush(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
}
EXPORT_SYMBOL_GPL(mt792x_flush);

+int mt792x_get_txpower(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
+ unsigned int link_id, int *dbm)
+{
+ struct mt76_power_limits limits = {};
+ struct ieee80211_bss_conf *link_conf;
+ struct ieee80211_channel *chan;
+ struct mt792x_bss_conf *mconf;
+ struct mt792x_vif *mvif;
+ struct mt76_phy *phy;
+ s8 max_power;
+
+ if (!vif)
+ return mt76_get_txpower(hw, vif, link_id, dbm);
+
+ mvif = (struct mt792x_vif *)vif->drv_priv;
+ phy = mvif->phy->mt76;
+
+ mt792x_mutex_acquire(mvif->phy->dev);
+
+ link_conf = mt792x_vif_to_bss_conf(vif, link_id);
+ mconf = link_conf ? mt792x_link_conf_to_mconf(link_conf) : NULL;
+ if (mconf && mconf->mt76.ctx && mconf->mt76.ctx->def.chan)
+ chan = mconf->mt76.ctx->def.chan;
+ else
+ /* Fall back to the current PHY chandef if the requested link
+ * does not have a valid channel context.
+ */
+ chan = phy->chandef.chan;
+
+ mt792x_mutex_release(mvif->phy->dev);
+
+ if (!chan)
+ return -EINVAL;
+
+ max_power = mt76_connac_get_rate_power_limit(phy, chan, &limits);
+ *dbm = DIV_ROUND_UP(max_power, 2);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mt792x_get_txpower);
+
int mt792x_assign_vif_chanctx(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
struct ieee80211_bss_conf *link_conf,
--
2.43.0