From 14437e3fa284f465dbbc8611fd4331ca8d60e986 Mon Sep 17 00:00:00 2001 From: Woojung Huh Date: Mon, 25 Apr 2016 22:22:36 +0000 Subject: [PATCH] lan78xx: workaround of forced 100 Full/Half duplex mode error At forced 100 Full & Half duplex mode, chip may fail to set mode correctly when cable is switched between long(~50+m) and short one. As workaround, set to 10 before setting to 100 at forced 100 F/H mode. Signed-off-by: Woojung Huh Signed-off-by: David S. Miller --- drivers/net/usb/lan78xx.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c index 0460b81a8784..f64778ad9753 100644 --- a/drivers/net/usb/lan78xx.c +++ b/drivers/net/usb/lan78xx.c @@ -1804,7 +1804,34 @@ static void lan78xx_remove_mdio(struct lan78xx_net *dev) static void lan78xx_link_status_change(struct net_device *net) { - /* nothing to do */ + struct phy_device *phydev = net->phydev; + int ret, temp; + + /* At forced 100 F/H mode, chip may fail to set mode correctly + * when cable is switched between long(~50+m) and short one. + * As workaround, set to 10 before setting to 100 + * at forced 100 F/H mode. + */ + if (!phydev->autoneg && (phydev->speed == 100)) { + /* disable phy interrupt */ + temp = phy_read(phydev, LAN88XX_INT_MASK); + temp &= ~LAN88XX_INT_MASK_MDINTPIN_EN_; + ret = phy_write(phydev, LAN88XX_INT_MASK, temp); + + temp = phy_read(phydev, MII_BMCR); + temp &= ~(BMCR_SPEED100 | BMCR_SPEED1000); + phy_write(phydev, MII_BMCR, temp); /* set to 10 first */ + temp |= BMCR_SPEED100; + phy_write(phydev, MII_BMCR, temp); /* set to 100 later */ + + /* clear pending interrupt generated while workaround */ + temp = phy_read(phydev, LAN88XX_INT_STS); + + /* enable phy interrupt back */ + temp = phy_read(phydev, LAN88XX_INT_MASK); + temp |= LAN88XX_INT_MASK_MDINTPIN_EN_; + ret = phy_write(phydev, LAN88XX_INT_MASK, temp); + } } static int lan78xx_phy_init(struct lan78xx_net *dev) -- 2.20.1