From: Jiawen Wu jiawenwu@trustnetic.com
[ Upstream commit c7b75bea853daeb64fc831dbf39a6bbabcc402ac ]
Clear MV_V2_PORT_CTRL_PWRDOWN bit to set power up for 88x3310 PHY, it sometimes does not take effect immediately. And a read of this register causes the bit not to clear. This will cause mv3310_reset() to time out, which will fail the config initialization. So add a delay before the next access.
Fixes: c9cc1c815d36 ("net: phy: marvell10g: place in powersave mode at probe") Signed-off-by: Jiawen Wu jiawenwu@trustnetic.com Reviewed-by: Russell King (Oracle) rmk+kernel@armlinux.org.uk Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/phy/marvell10g.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/net/phy/marvell10g.c b/drivers/net/phy/marvell10g.c index 2b64318efdba6..42b48d0d0c4ed 100644 --- a/drivers/net/phy/marvell10g.c +++ b/drivers/net/phy/marvell10g.c @@ -263,6 +263,13 @@ static int mv3310_power_up(struct phy_device *phydev) ret = phy_clear_bits_mmd(phydev, MDIO_MMD_VEND2, MV_V2_PORT_CTRL, MV_V2_PORT_CTRL_PWRDOWN);
+ /* Sometimes, the power down bit doesn't clear immediately, and + * a read of this register causes the bit not to clear. Delay + * 100us to allow the PHY to come out of power down mode before + * the next access. + */ + udelay(100); + if (phydev->drv->phy_id != MARVELL_PHY_ID_88X3310 || priv->firmware_ver < 0x00030000) return ret;