From d430dffbe9dd30759f3c64b65bf85b0245c8d8ab Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Tue, 21 Dec 2021 14:57:09 +0100 Subject: [PATCH] mt76: mt7921: fix a possible race enabling/disabling runtime-pm Fix a possible race enabling/disabling runtime-pm between mt7921_pm_set() and mt7921_poll_rx() since mt7921_pm_wake_work() always schedules rx-napi callback and it will trigger mt7921_pm_power_save_work routine putting chip to in low-power state during mt7921_pm_set processing. Suggested-by: Deren Wu Tested-by: Deren Wu Fixes: 1d8efc741df8 ("mt76: mt7921: introduce Runtime PM support") Signed-off-by: Lorenzo Bianconi Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/0f3e075a2033dc05f09dab4059e5be8cbdccc239.1640094847.git.lorenzo@kernel.org --- drivers/net/wireless/mediatek/mt76/mt76_connac_mac.c | 3 --- drivers/net/wireless/mediatek/mt76/mt7921/debugfs.c | 12 +++++++++--- 2 files changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/mt76_connac_mac.c b/drivers/net/wireless/mediatek/mt76/mt76_connac_mac.c index af43bcb54578..306e9eaea917 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76_connac_mac.c +++ b/drivers/net/wireless/mediatek/mt76/mt76_connac_mac.c @@ -7,9 +7,6 @@ int mt76_connac_pm_wake(struct mt76_phy *phy, struct mt76_connac_pm *pm) { struct mt76_dev *dev = phy->dev; - if (!pm->enable) - return 0; - if (mt76_is_usb(dev)) return 0; diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/debugfs.c b/drivers/net/wireless/mediatek/mt76/mt7921/debugfs.c index 7cdfdf83529f..86fd7292b229 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/debugfs.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/debugfs.c @@ -276,7 +276,7 @@ mt7921_pm_set(void *data, u64 val) struct mt7921_dev *dev = data; struct mt76_connac_pm *pm = &dev->pm; - mt7921_mutex_acquire(dev); + mutex_lock(&dev->mt76.mutex); if (val == pm->enable) goto out; @@ -285,7 +285,11 @@ mt7921_pm_set(void *data, u64 val) pm->stats.last_wake_event = jiffies; pm->stats.last_doze_event = jiffies; } - pm->enable = val; + /* make sure the chip is awake here and ps_work is scheduled + * just at end of the this routine. + */ + pm->enable = false; + mt76_connac_pm_wake(&dev->mphy, pm); ieee80211_iterate_active_interfaces(mt76_hw(dev), IEEE80211_IFACE_ITER_RESUME_ALL, @@ -293,8 +297,10 @@ mt7921_pm_set(void *data, u64 val) mt76_connac_mcu_set_deep_sleep(&dev->mt76, pm->ds_enable); + pm->enable = val; + mt76_connac_power_save_sched(&dev->mphy, pm); out: - mt7921_mutex_release(dev); + mutex_unlock(&dev->mt76.mutex); return 0; } -- 2.11.0