diff options
| author | Russell King <rmk+kernel@armlinux.org.uk> | 2017-12-12 10:45:36 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-03-19 08:42:43 +0100 |
| commit | 76fbc152cd8c95369b0527b5d5cb1e166033ab84 (patch) | |
| tree | 55c75a10760be0bbf25f9fcbe103dac90878d82a /drivers/net/phy/phy_device.c | |
| parent | 9b1fb9cc922dbf27959287ad75009bb388d115fe (diff) | |
net: phy: fix resume handling
[ Upstream commit f5e64032a799d4f54decc7eb6aafcdffb67f9ad9 ]
When a PHY has the BMCR_PDOWN bit set, it may decide to ignore writes
to other registers, or reset the registers to power-on defaults.
Micrel PHYs do this for their interrupt registers.
The current structure of phylib tries to enable interrupts before
resuming (and releasing) the BMCR_PDOWN bit. This fails, causing
Micrel PHYs to stop working after a suspend/resume sequence if they
are using interrupts.
Fix this by ensuring that the PHY driver resume methods do not take
the phydev->lock mutex themselves, but the callers of phy_resume()
take that lock. This then allows us to move the call to phy_resume()
before we enable interrupts in phy_start().
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net/phy/phy_device.c')
| -rw-r--r-- | drivers/net/phy/phy_device.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 67f25ac29025..b15b31ca2618 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -135,7 +135,9 @@ static int mdio_bus_phy_resume(struct device *dev) if (!mdio_bus_phy_may_suspend(phydev)) goto no_resume; + mutex_lock(&phydev->lock); ret = phy_resume(phydev); + mutex_unlock(&phydev->lock); if (ret < 0) return ret; @@ -1026,7 +1028,9 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev, if (err) goto error; + mutex_lock(&phydev->lock); phy_resume(phydev); + mutex_unlock(&phydev->lock); phy_led_triggers_register(phydev); return err; @@ -1157,6 +1161,8 @@ int phy_resume(struct phy_device *phydev) struct phy_driver *phydrv = to_phy_driver(phydev->mdio.dev.driver); int ret = 0; + WARN_ON(!mutex_is_locked(&phydev->lock)); + if (phydev->drv && phydrv->resume) ret = phydrv->resume(phydev); @@ -1639,13 +1645,9 @@ int genphy_resume(struct phy_device *phydev) { int value; - mutex_lock(&phydev->lock); - value = phy_read(phydev, MII_BMCR); phy_write(phydev, MII_BMCR, value & ~BMCR_PDOWN); - mutex_unlock(&phydev->lock); - return 0; } EXPORT_SYMBOL(genphy_resume); |