* [PATCH 2/3] wifi: mt76: connac: factor out rate power limit calculation
2026-03-25 4:33 [PATCH 1/3] wifi: mt76: connac: use a helper to cache txpower_cur Sean Wang
@ 2026-03-25 4:33 ` Sean Wang
2026-03-25 4:33 ` [PATCH 3/3] wifi: mt76: mt792x: report txpower for the requested vif link Sean Wang
2026-03-26 17:04 ` [PATCH 1/3] wifi: mt76: connac: use a helper to cache txpower_cur Lucid Duck
2 siblings, 0 replies; 4+ messages in thread
From: Sean Wang @ 2026-03-25 4:33 UTC (permalink / raw)
To: nbd, lorenzo.bianconi; +Cc: linux-wireless, linux-mediatek, Sean Wang
From: Sean Wang <sean.wang@mediatek.com>
Factor out the per-channel rate power limit calculation into a shared
helper.
This avoids duplicating the same regulatory, SAR and rate-limit logic in
multiple paths.
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
---
.../net/wireless/mediatek/mt76/mt76_connac.h | 3 ++
.../wireless/mediatek/mt76/mt76_connac_mcu.c | 28 +++++++++++++------
2 files changed, 23 insertions(+), 8 deletions(-)
diff --git a/drivers/net/wireless/mediatek/mt76/mt76_connac.h b/drivers/net/wireless/mediatek/mt76/mt76_connac.h
index d0953e02810b..1549a97873ee 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76_connac.h
+++ b/drivers/net/wireless/mediatek/mt76/mt76_connac.h
@@ -421,6 +421,9 @@ void mt76_connac_gen_ppe_thresh(u8 *he_ppet, int nss, enum nl80211_band band);
int mt76_connac_init_tx_queues(struct mt76_phy *phy, int idx, int n_desc,
int ring_base, void *wed, u32 flags);
void mt76_connac_set_txpower_cur(struct mt76_phy *phy, s8 max_power);
+s8 mt76_connac_get_rate_power_limit(struct mt76_phy *phy,
+ struct ieee80211_channel *chan,
+ struct mt76_power_limits *limits);
void mt76_connac_write_hw_txp(struct mt76_dev *dev,
struct mt76_tx_info *tx_info,
void *txp_ptr, u32 id);
diff --git a/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c b/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
index 897b065a2be6..1117a22c70ac 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
@@ -2223,15 +2223,10 @@ mt76_connac_mcu_rate_txpower_band(struct mt76_phy *phy,
.hw_value = ch_list[idx],
.band = band,
};
- s8 reg_power, sar_power, max_power;
-
- reg_power = mt76_connac_get_ch_power(phy, &chan,
- tx_power);
- sar_power = mt76_get_sar_power(phy, &chan, reg_power);
-
- max_power = mt76_get_rate_power_limits(phy, &chan, limits,
- sar_power);
+ s8 max_power;
+ max_power = mt76_connac_get_rate_power_limit(phy, &chan,
+ limits);
if (phy->chandef.chan &&
phy->chandef.chan->hw_value == ch_list[idx] &&
phy->chandef.chan->band == band)
@@ -2967,6 +2962,23 @@ int mt76_connac_mcu_rdd_cmd(struct mt76_dev *dev, int cmd, u8 index,
}
EXPORT_SYMBOL_GPL(mt76_connac_mcu_rdd_cmd);
+s8 mt76_connac_get_rate_power_limit(struct mt76_phy *phy,
+ struct ieee80211_channel *chan,
+ struct mt76_power_limits *limits)
+{
+ s8 reg_power, sar_power;
+ int tx_power;
+
+ tx_power = 2 * phy->hw->conf.power_level;
+ if (!tx_power)
+ tx_power = 127;
+
+ reg_power = mt76_connac_get_ch_power(phy, chan, tx_power);
+ sar_power = mt76_get_sar_power(phy, chan, reg_power);
+ return mt76_get_rate_power_limits(phy, chan, limits, sar_power);
+}
+EXPORT_SYMBOL_GPL(mt76_connac_get_rate_power_limit);
+
static int
mt76_connac_mcu_send_ram_firmware(struct mt76_dev *dev,
const struct mt76_connac2_fw_trailer *hdr,
--
2.43.0
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH 3/3] wifi: mt76: mt792x: report txpower for the requested vif link
2026-03-25 4:33 [PATCH 1/3] wifi: mt76: connac: use a helper to cache txpower_cur Sean Wang
2026-03-25 4:33 ` [PATCH 2/3] wifi: mt76: connac: factor out rate power limit calculation Sean Wang
@ 2026-03-25 4:33 ` Sean Wang
2026-03-26 17:04 ` [PATCH 1/3] wifi: mt76: connac: use a helper to cache txpower_cur Lucid Duck
2 siblings, 0 replies; 4+ messages in thread
From: Sean Wang @ 2026-03-25 4:33 UTC (permalink / raw)
To: nbd, lorenzo.bianconi; +Cc: linux-wireless, linux-mediatek, Sean Wang
From: Sean Wang <sean.wang@mediatek.com>
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.
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
---
.../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
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH 1/3] wifi: mt76: connac: use a helper to cache txpower_cur
2026-03-25 4:33 [PATCH 1/3] wifi: mt76: connac: use a helper to cache txpower_cur Sean Wang
2026-03-25 4:33 ` [PATCH 2/3] wifi: mt76: connac: factor out rate power limit calculation Sean Wang
2026-03-25 4:33 ` [PATCH 3/3] wifi: mt76: mt792x: report txpower for the requested vif link Sean Wang
@ 2026-03-26 17:04 ` Lucid Duck
2 siblings, 0 replies; 4+ messages in thread
From: Lucid Duck @ 2026-03-26 17:04 UTC (permalink / raw)
To: sean.wang; +Cc: nbd, lorenzo.bianconi, linux-wireless, linux-mediatek, morrownr
Sean,
Tested the full 3-patch series on MT7921AU. All three bands working
correctly -- txpower reporting is fixed.
Test environment:
Kernel: 6.19.8-200.fc43.x86_64 (Fedora 43)
Device: MediaTek MT7921AU USB (0e8d:7961)
Firmware: HW/SW 0x8a108a10, WM 20251223091148
AP: Tri-band (2.4/5/6 GHz)
Regdomain: CA (DFS-FCC), also tested US, JP, DE
Note: Internet maintained via separate USB ethernet
adapter during WiFi testing
Baseline (stock 6.19.8, pre-patch):
txpower 3.00 dBm on all bands
Post-patch txpower:
2.4 GHz ch 1 (2412 MHz, 20 MHz): 36.00 dBm
5 GHz ch 100 (5500 MHz, 80 MHz): 26.00 dBm
6 GHz ch 5 (5975 MHz, 80 MHz): 12.00 dBm
All values match expected CA regulatory limits. Connectivity verified
with 0% packet loss on every band.
Stress testing (28 tests, 28 passed, 0 failed):
- Connect/disconnect: 10 cycles per band (30 total), txpower
correct and ping 0% loss on every cycle
- Band switching: 30 sequential hops (2.4 -> 5 -> 6 -> repeat),
txpower correct on every hop, ping 30/30
- Module reload: 15 full rmmod/insmod cycles of all mt76 modules,
txpower correct after every reload
- Throughput: 100-ping per band, 0% loss on all
2.4 GHz: avg 2.4 ms, max 23.6 ms
5 GHz: avg 1.9 ms, max 8.0 ms
6 GHz: avg 2.2 ms, max 3.3 ms
- Soak: 20-minute continuous test per band (60 min total),
txpower sampled every 30 seconds, never deviated
2.4 GHz: 40/40 samples at 36.00 dBm, slab delta -4 kB
5 GHz: 40/40 samples at 26.00 dBm, slab delta +16 kB
6 GHz: 40/40 samples at 12.00 dBm, slab delta -16 kB
- Memory: 50 connect/disconnect cycles, slab delta +64 kB
(negligible, no leak)
- Band-hop marathon: 200 random band hops, 200/200 pass,
ping 200/200 OK, completed in 1232 seconds
- Concurrent managed + monitor: txpower stable on all bands
with a monitor VIF present, ping 0% loss
- Regulatory domain switching: txpower correctly adjusts
per country on 5 GHz
CA: 26.00 dBm
US: 24.00 dBm
JP: 23.00 dBm
DE: 26.00 dBm
Zero kernel warnings in dmesg throughout all testing.
For context, I originally reported this bug and submitted a fix in
January (v1 through v4 on linux-wireless, as Lucid Duck). Patches 1
and 2 in this series address the same core issue -- capturing the rate
power loop output and subtracting the path delta before caching
txpower_cur. Patch 3 (the per-vif-link get_txpower callback) is a
good addition that was not in my series.
Reported-by: Lucid Duck <lucid_duck@justthetip.ca>
Tested-by: Lucid Duck <lucid_duck@justthetip.ca>
^ permalink raw reply [flat|nested] 4+ messages in thread