by Lorenzo Bianconi

[permalink] [raw]

Subject: [PATCH 01/19] mt76: mt7921: fix a race between mt7921_mcu_drv_pmctrl and mt7921_mcu_fw_pmctrl

Introduce a mutex in order to avoid a race between mt7921_mcu_drv_pmctrl and
mt7921_mcu_fw_pmctrl routines since they are run two independent works

Fixes: 1d8efc741df8 ("mt76: mt7921: introduce Runtime PM support")
Signed-off-by: Lorenzo Bianconi <[email protected]>
---
.../net/wireless/mediatek/mt76/mt76_connac.h | 1 +
.../net/wireless/mediatek/mt76/mt7921/init.c | 1 +
.../net/wireless/mediatek/mt76/mt7921/mcu.c | 34 +++++++++++++------
3 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt76_connac.h b/drivers/net/wireless/mediatek/mt76/mt76_connac.h
index b811f3c410a1..2b31c9794e92 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76_connac.h
+++ b/drivers/net/wireless/mediatek/mt76/mt76_connac.h
@@ -54,6 +54,7 @@ struct mt76_connac_pm {

struct work_struct wake_work;
struct completion wake_cmpl;
+ struct mutex mutex;

struct delayed_work ps_work;
unsigned long last_activity;
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/init.c b/drivers/net/wireless/mediatek/mt76/mt7921/init.c
index eab6e2dcdb96..0b8a5a7f4362 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/init.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/init.c
@@ -222,6 +222,7 @@ int mt7921_register_device(struct mt7921_dev *dev)

INIT_DELAYED_WORK(&dev->pm.ps_work, mt7921_pm_power_save_work);
INIT_WORK(&dev->pm.wake_work, mt7921_pm_wake_work);
+ mutex_init(&dev->pm.mutex);
init_completion(&dev->pm.wake_cmpl);
spin_lock_init(&dev->pm.txq_lock);
set_bit(MT76_STATE_PM, &dev->mphy.state);
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c
index 14ba856de0b6..ea00f6b6af56 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c
@@ -1267,9 +1267,11 @@ int mt7921_mcu_set_bss_pm(struct mt7921_dev *dev, struct ieee80211_vif *vif,
int mt7921_mcu_drv_pmctrl(struct mt7921_dev *dev)
{
struct mt76_phy *mphy = &dev->mt76.phy;
- int i;
+ int i, err = 0;

- if (!test_and_clear_bit(MT76_STATE_PM, &mphy->state))
+ mutex_lock(&dev->pm.mutex);
+
+ if (!test_bit(MT76_STATE_PM, &mphy->state))
goto out;

for (i = 0; i < MT7921_DRV_OWN_RETRY_COUNT; i++) {
@@ -1281,23 +1283,30 @@ int mt7921_mcu_drv_pmctrl(struct mt7921_dev *dev)

if (i == MT7921_DRV_OWN_RETRY_COUNT) {
dev_err(dev->mt76.dev, "driver own failed\n");
- mt7921_reset(&dev->mt76);
- return -EIO;
+ err = -EIO;
+ goto out;
}
+ clear_bit(MT76_STATE_PM, &mphy->state);

out:
dev->pm.last_activity = jiffies;
+ mutex_unlock(&dev->pm.mutex);

- return 0;
+ if (err)
+ mt7921_reset(&dev->mt76);
+
+ return err;
}

int mt7921_mcu_fw_pmctrl(struct mt7921_dev *dev)
{
struct mt76_phy *mphy = &dev->mt76.phy;
- int i;
+ int i, err = 0;
+
+ mutex_lock(&dev->pm.mutex);

if (test_and_set_bit(MT76_STATE_PM, &mphy->state))
- return 0;
+ goto out;

for (i = 0; i < MT7921_DRV_OWN_RETRY_COUNT; i++) {
mt76_wr(dev, MT_CONN_ON_LPCTL, PCIE_LPCR_HOST_SET_OWN);
@@ -1308,11 +1317,16 @@ int mt7921_mcu_fw_pmctrl(struct mt7921_dev *dev)

if (i == MT7921_DRV_OWN_RETRY_COUNT) {
dev_err(dev->mt76.dev, "firmware own failed\n");
- mt7921_reset(&dev->mt76);
- return -EIO;
+ clear_bit(MT76_STATE_PM, &mphy->state);
+ err = -EIO;
}
+out:
+ mutex_unlock(&dev->pm.mutex);

- return 0;
+ if (err)
+ mt7921_reset(&dev->mt76);
+
+ return err;
}

void
--
2.30.2