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From:   Laurent Badel <laurentbadel@eaton.com>
To:     <netdev@vger.kernel.org>, Andrew Lunn <andrew@lunn.ch>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        "David S . Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        <linux-kernel@vger.kernel.org>,
        "Rafael J . Wysocki" <rjw@rjwysocki.net>,
        Pavel Machek <pavel@ucw.cz>, <linux-pm@vger.kernel.org>
CC:     Laurent Badel <laurentbadel@eaton.com>
Subject: [PATCH net 0/1] net: phy: Fix interrupt mask loss on resume from hibernation
Date:   Fri, 22 Jan 2021 15:35:23 +0100
Message-ID: <20210122143524.14516-1-laurentbadel@eaton.com>
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=EF=BB=BFSome PHYs such as SMSC LAN87xx clear the interrupt mask register o=
n
software reset. Since mdio_bus_phy_restore() calls phy_init_hw() which
does a software reset of the PHY, these PHYs will lose their interrupt=20
mask configuration on resuming from hibernation.

I initially reconfigured only the PHY interrupt mask using=20
phydev->config_intr(), which worked fine with PM_DEBUG/test_resume, but
there seems to be an issue when resuming from a real hibernation, by which
the interrupt type is not set appropriately (in this case=20
IRQ_TYPE_LEVEL_LOW). Calling irq_set_irq_type() directly from sysfs=20
restored the PHY functionality immediately suggesting that everything is
otherwise well configured. Therefore this patch suggests freeing and
re-requesting the interrupt, to guarantee proper interrupt configuration.

Laurent Badel (1):
  net: phy: Reconfigure PHY interrupt in mdio_bus_phy_restore()

 drivers/net/phy/phy_device.c | 9 +++++++++
 1 file changed, 9 insertions(+)

--=20
2.17.1


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