From 726dd7f8f45b2938bea63ac66ab933408001565d Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Wed, 20 Mar 2019 15:02:00 +0100 Subject: [PATCH] net: ks8851: Set initial carrier state to down The ks8851 chip's initial carrier state is down. A Link Change Interrupt is signaled once interrupts are enabled if the carrier is up. The ks8851 driver has it backwards by assuming that the initial carrier state is up. The state is therefore misrepresented if the interface is opened with no cable attached. Fix it. The Link Change interrupt is sometimes not signaled unless the P1MBSR register (which contains the Link Status bit) is read on ->ndo_open(). This might be a hardware erratum. Read the register by calling mii_check_link(), which has the desirable side effect of setting the carrier state to down if the cable was detached while the interface was closed. Signed-off-by: Lukas Wunner Cc: Frank Pavlic Cc: Ben Dooks Cc: Tristram Ha Signed-off-by: David S. Miller --- drivers/net/ethernet/micrel/ks8851.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/ethernet/micrel/ks8851.c b/drivers/net/ethernet/micrel/ks8851.c index c9faec4c5b255..b83b070a9eec8 100644 --- a/drivers/net/ethernet/micrel/ks8851.c +++ b/drivers/net/ethernet/micrel/ks8851.c @@ -858,6 +858,7 @@ static int ks8851_net_open(struct net_device *dev) netif_dbg(ks, ifup, ks->netdev, "network device up\n"); mutex_unlock(&ks->lock); + mii_check_link(&ks->mii); return 0; } @@ -1519,6 +1520,7 @@ static int ks8851_probe(struct spi_device *spi) spi_set_drvdata(spi, ks); + netif_carrier_off(ks->netdev); ndev->if_port = IF_PORT_100BASET; ndev->netdev_ops = &ks8851_netdev_ops; ndev->irq = spi->irq; -- 2.39.5