diff options
Diffstat (limited to 'target/linux/mvebu/patches-4.9/414-phy-add-I2C-mdio-bus.patch')
| -rw-r--r-- | target/linux/mvebu/patches-4.9/414-phy-add-I2C-mdio-bus.patch | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/target/linux/mvebu/patches-4.9/414-phy-add-I2C-mdio-bus.patch b/target/linux/mvebu/patches-4.9/414-phy-add-I2C-mdio-bus.patch new file mode 100644 index 0000000..c389817 --- /dev/null +++ b/target/linux/mvebu/patches-4.9/414-phy-add-I2C-mdio-bus.patch @@ -0,0 +1,180 @@ +From: Russell King <rmk+kernel@arm.linux.org.uk> +Date: Fri, 25 Sep 2015 17:43:52 +0100 +Subject: [PATCH] phy: add I2C mdio bus + +Add an I2C MDIO bus bridge library, to allow phylib to access PHYs which +are connected to an I2C bus instead of the more conventional MDIO bus. +Such PHYs can be found in SFP adapters and SFF modules. + +Since PHYs appear at I2C bus address 0x40..0x5f, and 0x50/0x51 are +reserved for SFP EEPROMs/diagnostics, we must not allow the MDIO bus +to access these I2C addresses. + +Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> +--- + create mode 100644 drivers/net/phy/mdio-i2c.c + create mode 100644 drivers/net/phy/mdio-i2c.h + +--- a/drivers/net/phy/Kconfig ++++ b/drivers/net/phy/Kconfig +@@ -105,6 +105,16 @@ config MDIO_HISI_FEMAC + This module provides a driver for the MDIO busses found in the + Hisilicon SoC that have an Fast Ethernet MAC. + ++config MDIO_I2C ++ tristate ++ depends on I2C ++ help ++ Support I2C based PHYs. This provides a MDIO bus bridged ++ to I2C to allow PHYs connected in I2C mode to be accessed ++ using the existing infrastructure. ++ ++ This is library mode. ++ + config MDIO_MOXART + tristate "MOXA ART MDIO interface support" + depends on ARCH_MOXART +--- a/drivers/net/phy/Makefile ++++ b/drivers/net/phy/Makefile +@@ -33,6 +33,7 @@ obj-$(CONFIG_MDIO_BUS_MUX_MMIOREG) += md + obj-$(CONFIG_MDIO_CAVIUM) += mdio-cavium.o + obj-$(CONFIG_MDIO_GPIO) += mdio-gpio.o + obj-$(CONFIG_MDIO_HISI_FEMAC) += mdio-hisi-femac.o ++obj-$(CONFIG_MDIO_I2C) += mdio-i2c.o + obj-$(CONFIG_MDIO_MOXART) += mdio-moxart.o + obj-$(CONFIG_MDIO_OCTEON) += mdio-octeon.o + obj-$(CONFIG_MDIO_SUN4I) += mdio-sun4i.o +--- /dev/null ++++ b/drivers/net/phy/mdio-i2c.c +@@ -0,0 +1,109 @@ ++/* ++ * MDIO I2C bridge ++ * ++ * Copyright (C) 2015-2016 Russell King ++ * ++ * This program is free software; you can redistribute it and/or modify ++ * it under the terms of the GNU General Public License version 2 as ++ * published by the Free Software Foundation. ++ * ++ * Network PHYs can appear on I2C buses when they are part of SFP module. ++ * This driver exposes these PHYs to the networking PHY code, allowing ++ * our PHY drivers access to these PHYs, and so allowing configuration ++ * of their settings. ++ */ ++#include <linux/i2c.h> ++#include <linux/phy.h> ++ ++#include "mdio-i2c.h" ++ ++/* ++ * I2C bus addresses 0x50 and 0x51 are normally an EEPROM, which is ++ * specified to be present in SFP modules. These correspond with PHY ++ * addresses 16 and 17. Disallow access to these "phy" addresses. ++ */ ++static bool i2c_mii_valid_phy_id(int phy_id) ++{ ++ return phy_id != 0x10 && phy_id != 0x11; ++} ++ ++static unsigned int i2c_mii_phy_addr(int phy_id) ++{ ++ return phy_id + 0x40; ++} ++ ++static int i2c_mii_read(struct mii_bus *bus, int phy_id, int reg) ++{ ++ struct i2c_adapter *i2c = bus->priv; ++ struct i2c_msg msgs[2]; ++ u8 data[2], dev_addr = reg; ++ int bus_addr, ret; ++ ++ if (!i2c_mii_valid_phy_id(phy_id)) ++ return 0xffff; ++ ++ bus_addr = i2c_mii_phy_addr(phy_id); ++ msgs[0].addr = bus_addr; ++ msgs[0].flags = 0; ++ msgs[0].len = 1; ++ msgs[0].buf = &dev_addr; ++ msgs[1].addr = bus_addr; ++ msgs[1].flags = I2C_M_RD; ++ msgs[1].len = sizeof(data); ++ msgs[1].buf = data; ++ ++ ret = i2c_transfer(i2c, msgs, ARRAY_SIZE(msgs)); ++ if (ret != ARRAY_SIZE(msgs)) ++ return 0xffff; ++ ++ return data[0] << 8 | data[1]; ++} ++ ++static int i2c_mii_write(struct mii_bus *bus, int phy_id, int reg, u16 val) ++{ ++ struct i2c_adapter *i2c = bus->priv; ++ struct i2c_msg msg; ++ int ret; ++ u8 data[3]; ++ ++ if (!i2c_mii_valid_phy_id(phy_id)) ++ return 0; ++ ++ data[0] = reg; ++ data[1] = val >> 8; ++ data[2] = val; ++ ++ msg.addr = i2c_mii_phy_addr(phy_id); ++ msg.flags = 0; ++ msg.len = 3; ++ msg.buf = data; ++ ++ ret = i2c_transfer(i2c, &msg, 1); ++ ++ return ret < 0 ? ret : 0; ++} ++ ++struct mii_bus *mdio_i2c_alloc(struct device *parent, struct i2c_adapter *i2c) ++{ ++ struct mii_bus *mii; ++ ++ if (!i2c_check_functionality(i2c, I2C_FUNC_I2C)) ++ return ERR_PTR(-EINVAL); ++ ++ mii = mdiobus_alloc(); ++ if (!mii) ++ return ERR_PTR(-ENOMEM); ++ ++ snprintf(mii->id, MII_BUS_ID_SIZE, "i2c:%s", dev_name(parent)); ++ mii->parent = parent; ++ mii->read = i2c_mii_read; ++ mii->write = i2c_mii_write; ++ mii->priv = i2c; ++ ++ return mii; ++} ++EXPORT_SYMBOL_GPL(mdio_i2c_alloc); ++ ++MODULE_AUTHOR("Russell King"); ++MODULE_DESCRIPTION("MDIO I2C bridge library"); ++MODULE_LICENSE("GPL v2"); +--- /dev/null ++++ b/drivers/net/phy/mdio-i2c.h +@@ -0,0 +1,19 @@ ++/* ++ * MDIO I2C bridge ++ * ++ * Copyright (C) 2015 Russell King ++ * ++ * This program is free software; you can redistribute it and/or modify ++ * it under the terms of the GNU General Public License version 2 as ++ * published by the Free Software Foundation. ++ */ ++#ifndef MDIO_I2C_H ++#define MDIO_I2C_H ++ ++struct device; ++struct i2c_adapter; ++struct mii_bus; ++ ++struct mii_bus *mdio_i2c_alloc(struct device *parent, struct i2c_adapter *i2c); ++ ++#endif |