From: Dejin Zheng zhengdejin5@gmail.com
[ Upstream commit 6d61f483f148b856d47a6c96d5d84054d5a9f849 ]
Commit 7ae7ad2f11ef47 ("net: phy: smsc: use phy_read_poll_timeout() to simplify the code") will print a lot of logs as follows when Ethernet cable is not connected:
[ 4.473105] SMSC LAN8710/LAN8720 2188000.ethernet-1:00: lan87xx_read_status failed: -110
When wait 640 ms for check ENERGYON bit, the timeout should not be regarded as an actual error and an error message also should not be printed. due to a hardware bug in LAN87XX device, it leads to unstable detection of plugging in Ethernet cable when LAN87xx is in Energy Detect Power-Down mode. the workaround for it involves, when the link is down, and at each read_status() call:
- disable EDPD mode, forcing the PHY out of low-power mode - waiting 640ms to see if we have any energy detected from the media - re-enable entry to EDPD mode
This is presumably enough to allow the PHY to notice that a cable is connected, and resume normal operations to negotiate with the partner. The problem is that when no media is detected, the 640ms wait times out and this commit was modified to prints an error message. it is an inappropriate conversion by used phy_read_poll_timeout() to introduce this bug. so fix this issue by use read_poll_timeout() to replace phy_read_poll_timeout().
Fixes: 7ae7ad2f11ef47 ("net: phy: smsc: use phy_read_poll_timeout() to simplify the code") Reported-by: Kevin Groeneveld kgroeneveld@gmail.com Signed-off-by: Dejin Zheng zhengdejin5@gmail.com Reviewed-by: Andrew Lunn andrew@lunn.ch Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/phy/smsc.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/net/phy/smsc.c b/drivers/net/phy/smsc.c index 93da7d3d0954c..74568ae161253 100644 --- a/drivers/net/phy/smsc.c +++ b/drivers/net/phy/smsc.c @@ -122,10 +122,13 @@ static int lan87xx_read_status(struct phy_device *phydev) if (rc < 0) return rc;
- /* Wait max 640 ms to detect energy */ - phy_read_poll_timeout(phydev, MII_LAN83C185_CTRL_STATUS, rc, - rc & MII_LAN83C185_ENERGYON, 10000, - 640000, true); + /* Wait max 640 ms to detect energy and the timeout is not + * an actual error. + */ + read_poll_timeout(phy_read, rc, + rc & MII_LAN83C185_ENERGYON || rc < 0, + 10000, 640000, true, phydev, + MII_LAN83C185_CTRL_STATUS); if (rc < 0) return rc;