Date:   Tue, 7 Dec 2021 11:08:49 +0100
From:   Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
To:     sean.wang@mediatek.com
Cc:     nbd@nbd.name, Soul.Huang@mediatek.com, YN.Chen@mediatek.com,
        Leon.Yen@mediatek.com, Eric-SY.Chang@mediatek.com,
        Mark-YW.Chen@mediatek.com, Deren.Wu@mediatek.com,
        km.lin@mediatek.com, robin.chiu@mediatek.com,
        Eddie.Chen@mediatek.com, ch.yeh@mediatek.com,
        posh.sun@mediatek.com, ted.huang@mediatek.com,
        Eric.Liang@mediatek.com, Stella.Chang@mediatek.com,
        Tom.Chou@mediatek.com, steve.lee@mediatek.com, jsiuda@google.com,
        frankgor@google.com, jemele@google.com, abhishekpandit@google.com,
        shawnku@google.com, linux-wireless@vger.kernel.org,
        linux-mediatek@lists.infradead.org
Subject: Re: [PATCH] mt76: mt7921: fix possible resume failure
Message-ID: <Ya8ysehFjoEGGEf+@lore-desk>
References: <ff1e35dcaa0a56c04339bba2ebd2c68bf815919c.1638844068.git.objelf@gmail.com>
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> From: Sean Wang <sean.wang@mediatek.com>
>=20
> Fix the possible resume failure due to mt76_connac_mcu_set_hif_suspend
> timeout.
>=20
> 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.

do we have a similar issue in mt7921s_resume()?

>=20
> 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>
> ---
>  drivers/net/wireless/mediatek/mt76/mt7921/pci.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
>=20
> diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c b/drivers/ne=
t/wireless/mediatek/mt76/mt7921/pci.c
> index 5635de3c80b1..21a48f02ab60 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
> +++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
> @@ -315,7 +315,6 @@ static int mt7921_pci_resume(struct pci_dev *pdev)
>  	struct mt76_connac_pm *pm =3D &dev->pm;
>  	int i, err;
> =20
> -	pm->suspended =3D false;
>  	err =3D pci_set_power_state(pdev, PCI_D0);
>  	if (err)
>  		return err;
> @@ -353,7 +352,11 @@ static int mt7921_pci_resume(struct pci_dev *pdev)
>  	if (!pm->ds_enable)
>  		mt76_connac_mcu_set_deep_sleep(&dev->mt76, false);
> =20
> -	return mt76_connac_mcu_set_hif_suspend(mdev, false);
> +	err =3D mt76_connac_mcu_set_hif_suspend(mdev, false);
> +
> +	pm->suspended =3D false;
> +
> +	return err;
>  }
>  #endif /* CONFIG_PM */
> =20
> --=20
> 2.25.1
>=20

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