diff mbox series

[v2,1/4] mt76: mt7921e: fix race issue between reset and suspend/resume

Message ID 5f835553ee8b76e4a4ed83f9562eaa0b1a24c1e6.1658355599.git.sean.wang@kernel.org (mailing list archive)
State Accepted
Delegated to: Felix Fietkau
Headers show
Series [v2,1/4] mt76: mt7921e: fix race issue between reset and suspend/resume | expand

Commit Message

Sean Wang July 20, 2022, 10:25 p.m. UTC 
From: Sean Wang <sean.wang@mediatek.com>

It is unexpected that the reset work is running simultaneously with
the suspend or resume context and it is possible that reset work is still
running even after mt7921 is suspended if we don't fix the race issue.

Thus, the suspend procedure should be waiting until the reset is completed
at the beginning and ignore the subsequent the reset requests.

In case there is an error that happens during either suspend or resume
handler, we will schedule a reset task to recover the error before
returning the error code to ensure we can immediately fix the error there.

Fixes: 0c1ce9884607 ("mt76: mt7921: add wifi reset support")
Co-developed-by: YN Chen <YN.Chen@mediatek.com>
Signed-off-by: YN Chen <YN.Chen@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
---
v2: use flush_work instead of cancel_work_sync
---
 drivers/net/wireless/mediatek/mt76/mt7921/mac.c |  5 +++++
 drivers/net/wireless/mediatek/mt76/mt7921/pci.c | 13 +++++++++----
 2 files changed, 14 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c
index 47f0aa81ab02..6bd9fc9228a2 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c
@@ -780,6 +780,7 @@  void mt7921_mac_reset_work(struct work_struct *work)
 void mt7921_reset(struct mt76_dev *mdev)
 {
 	struct mt7921_dev *dev = container_of(mdev, struct mt7921_dev, mt76);
+	struct mt76_connac_pm *pm = &dev->pm;
 
 	if (!dev->hw_init_done)
 		return;
@@ -787,8 +788,12 @@  void mt7921_reset(struct mt76_dev *mdev)
 	if (dev->hw_full_reset)
 		return;
 
+	if (pm->suspended)
+		return;
+
 	queue_work(dev->mt76.wq, &dev->reset_work);
 }
+EXPORT_SYMBOL_GPL(mt7921_reset);
 
 void mt7921_mac_update_mib_stats(struct mt7921_phy *phy)
 {
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
index 9d1ba838e54f..a88561a4e903 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
@@ -363,6 +363,7 @@  static int mt7921_pci_suspend(struct device *device)
 	int i, err;
 
 	pm->suspended = true;
+	flush_work(&dev->reset_work);
 	cancel_delayed_work_sync(&pm->ps_work);
 	cancel_work_sync(&pm->wake_work);
 
@@ -424,6 +425,9 @@  static int mt7921_pci_suspend(struct device *device)
 restore_suspend:
 	pm->suspended = false;
 
+	if (err < 0)
+		mt7921_reset(&dev->mt76);
+
 	return err;
 }
 
@@ -437,7 +441,7 @@  static int mt7921_pci_resume(struct device *device)
 
 	err = mt7921_mcu_drv_pmctrl(dev);
 	if (err < 0)
-		return err;
+		goto failed;
 
 	mt7921_wpdma_reinit_cond(dev);
 
@@ -467,11 +471,12 @@  static int mt7921_pci_resume(struct device *device)
 		mt76_connac_mcu_set_deep_sleep(&dev->mt76, false);
 
 	err = mt76_connac_mcu_set_hif_suspend(mdev, false);
-	if (err)
-		return err;
-
+failed:
 	pm->suspended = false;
 
+	if (err < 0)
+		mt7921_reset(&dev->mt76);
+
 	return err;
 }