From 5375001bb4ce22801bf3bb566cc3e67d2d3a5dc0 Mon Sep 17 00:00:00 2001
From: Sean Wang <sean.wang@mediatek.com>
Date: Thu, 16 Dec 2021 05:25:35 +0800
Subject: [PATCH] mt76: mt7921: fix possible resume failure
Git-commit: 5375001bb4ce22801bf3bb566cc3e67d2d3a5dc0
Patch-mainline: v5.17-rc1
References: git-fixes

Fix the possible resume failure due to mt76_connac_mcu_set_hif_suspend
timeout.

That is because clearing the flag pm->suspended too early opened up a race
window, where mt7921_poll_tx/rx scheduled a ps_work to put the device in
doze mode, that is unexpected for the device is being resumed from the
suspend state and would make the remaining MCU comamnds in resume handler
failed to execute.

Fixes: ffa1bf97425b ("mt76: mt7921: introduce PM 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>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/wireless/mediatek/mt76/mt7921/pci.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
@@ -273,7 +273,6 @@ static int mt7921_pci_resume(struct pci_
 	struct mt76_connac_pm *pm = &dev->pm;
 	int i, err;
 
-	pm->suspended = false;
 	err = pci_set_power_state(pdev, PCI_D0);
 	if (err)
 		return err;
@@ -311,6 +310,11 @@ static int mt7921_pci_resume(struct pci_
 	if (!test_bit(MT76_STATE_SUSPEND, &dev->mphy.state))
 		err = mt76_connac_mcu_set_hif_suspend(mdev, false);
 
+	if (err)
+		return err;
+
+	pm->suspended = false;
+
 	return err;
 }
 #endif /* CONFIG_PM */