From 68502f802a66b68a6b5fefb52e709807a702a94b Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Mon, 26 Nov 2018 19:46:58 +0000 Subject: [PATCH 443/454] net: lan78xx: Support auto-downshift to 100Mb/s Ethernet cables with faulty or missing pairs (specifically pairs C and D) allow auto-negotiation to 1000Mbs, but do not support the successful establishment of a link. Add a DT property, "microchip,downshift-after", to configure the number of auto-negotiation failures after which it falls back to 100Mbs. Valid values are 2, 3, 4, 5 and 0, where 0 means never downshift. Signed-off-by: Phil Elwell --- drivers/net/phy/microchip.c | 33 +++++++++++++++++++++++++++++++++ drivers/net/usb/lan78xx.c | 8 ++++++-- include/linux/microchipphy.h | 11 +++++++++++ 3 files changed, 50 insertions(+), 2 deletions(-) --- a/drivers/net/phy/microchip.c +++ b/drivers/net/phy/microchip.c @@ -21,6 +21,7 @@ #include #include #include +#include #define DRIVER_AUTHOR "WOOJUNG HUH " #define DRIVER_DESC "Microchip LAN88XX PHY driver" @@ -225,6 +226,7 @@ static int lan88xx_probe(struct phy_devi { struct device *dev = &phydev->mdio.dev; struct lan88xx_priv *priv; + u32 downshift_after = 0; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) @@ -232,6 +234,37 @@ static int lan88xx_probe(struct phy_devi priv->wolopts = 0; + if (!of_property_read_u32(dev->of_node, + "microchip,downshift-after", + &downshift_after)) { + u32 mask = LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_MASK; + u32 val = LAN78XX_PHY_CTRL3_AUTO_DOWNSHIFT; + + switch (downshift_after) { + case 2: + val |= LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_2; + break; + case 3: + val |= LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_3; + break; + case 4: + val |= LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_4; + break; + case 5: + val |= LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_5; + break; + case 0: + /* Disable completely */ + mask = LAN78XX_PHY_CTRL3_AUTO_DOWNSHIFT; + val = 0; + break; + default: + return -EINVAL; + } + (void)phy_modify_paged(phydev, 1, LAN78XX_PHY_CTRL3, + mask, val); + } + /* these values can be used to identify internal PHY */ priv->chip_id = phy_read_mmd(phydev, 3, LAN88XX_MMD3_CHIP_ID); priv->chip_rev = phy_read_mmd(phydev, 3, LAN88XX_MMD3_CHIP_REV); --- a/drivers/net/usb/lan78xx.c +++ b/drivers/net/usb/lan78xx.c @@ -37,7 +37,8 @@ #include #include #include -#include +#include +#include #include #include "lan78xx.h" @@ -1764,6 +1765,7 @@ done: static int lan78xx_mdio_init(struct lan78xx_net *dev) { + struct device_node *node; int ret; dev->mdiobus = mdiobus_alloc(); @@ -1793,7 +1795,9 @@ static int lan78xx_mdio_init(struct lan7 break; } - ret = mdiobus_register(dev->mdiobus); + node = of_get_child_by_name(dev->udev->dev.of_node, "mdio"); + ret = of_mdiobus_register(dev->mdiobus, node); + of_node_put(node); if (ret) { netdev_err(dev->net, "can't register MDIO bus\n"); goto exit1; --- a/include/linux/microchipphy.h +++ b/include/linux/microchipphy.h @@ -70,6 +70,17 @@ #define LAN88XX_MMD3_CHIP_ID (32877) #define LAN88XX_MMD3_CHIP_REV (32878) +/* Registers specific to the LAN7800/LAN7850 embedded phy */ +#define LAN78XX_PHY_LED_MODE_SELECT (0x1D) + +#define LAN78XX_PHY_CTRL3 (0x14) +#define LAN78XX_PHY_CTRL3_AUTO_DOWNSHIFT (0x0010) +#define LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_MASK (0x000c) +#define LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_2 (0x0000) +#define LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_3 (0x0004) +#define LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_4 (0x0008) +#define LAN78XX_PHY_CTRL3_DOWNSHIFT_CTRL_5 (0x000c) + /* DSP registers */ #define PHY_ARDENNES_MMD_DEV_3_PHY_CFG (0x806A) #define PHY_ARDENNES_MMD_DEV_3_PHY_CFG_ZD_DLY_EN_ (0x2000)