From c7ddb74c981c1a29bad82d555d08724aca93b687 Mon Sep 17 00:00:00 2001 From: Sander Vanheule Date: Fri, 27 Dec 2024 14:55:31 +0100 Subject: [PATCH] net: mdio: Add Realtek Otto auxiliary controller SoCs in Realtek's Otto platform such as the RTL8380 and RTL8391 have a simple auxiliary MDIO controller that is commonly used to manage RTL8231 GPIO expanders on switch devices. Add a new MDIO controller driver supporting the RTL838x (maple) and RTL839x (cypress) SoCs. Signed-off-by: Sander Vanheule --- drivers/net/mdio/Kconfig | 10 ++ drivers/net/mdio/Makefile | 1 + drivers/net/mdio/mdio-realtek-otto-aux.c | 129 +++++++++++++++++++++++ 3 files changed, 140 insertions(+) create mode 100644 drivers/net/mdio/mdio-realtek-otto-aux.c --- a/drivers/net/mdio/Kconfig +++ b/drivers/net/mdio/Kconfig @@ -207,6 +207,16 @@ config MDIO_REGMAP regmap. Users willing to use this driver must explicitly select REGMAP. +config MDIO_REALTEK_OTTO_AUX + tristate "Realtek Otto auxiliary MDIO interface support" + default MACH_REALTEK_RTL + depends on MACH_REALTEK_RTL + depends on MFD_SYSCON + select MDIO_DEVRES + help + This driver supports the auxilairy MDIO bus on RTL838x SoCs. This bus + is typically used to attach RTL8231 GPIO extenders. + config MDIO_THUNDER tristate "ThunderX SOCs MDIO buses" depends on 64BIT --- a/drivers/net/mdio/Makefile +++ b/drivers/net/mdio/Makefile @@ -20,6 +20,7 @@ obj-$(CONFIG_MDIO_MSCC_MIIM) += mdio-ms obj-$(CONFIG_MDIO_MVUSB) += mdio-mvusb.o obj-$(CONFIG_MDIO_OCTEON) += mdio-octeon.o obj-$(CONFIG_MDIO_REGMAP) += mdio-regmap.o +obj-$(CONFIG_MDIO_REALTEK_OTTO_AUX) += mdio-realtek-otto-aux.o obj-$(CONFIG_MDIO_SMBUS) += mdio-smbus.o obj-$(CONFIG_MDIO_SUN4I) += mdio-sun4i.o obj-$(CONFIG_MDIO_THUNDER) += mdio-thunder.o --- /dev/null +++ b/drivers/net/mdio/mdio-realtek-otto-aux.c @@ -0,0 +1,141 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define RTL8380_EXT_GPIO_INDIRECT_ACCESS 0xA09C +#define RTL8390_EXT_GPIO_INDIRECT_ACCESS 0x0224 + +#define RTL83XX_AUX_MDIO_DATA GENMASK(31, 16) +#define RTL83XX_AUX_MDIO_REG GENMASK(11, 7) +#define RTL83XX_AUX_MDIO_PHY_ADDR GENMASK(6, 2) +#define RTL83XX_AUX_MDIO_WRITE BIT(1) +#define RTL83XX_AUX_MDIO_READ 0 +#define RTL83XX_AUX_MDIO_EXEC BIT(0) + +struct realtek_aux_mdio_ctrl { + struct device *dev; + struct regmap *map; + unsigned int cmd_reg; +}; + +#define mii_bus_to_ctrl(bus) ((struct realtek_aux_mdio_ctrl *) bus->priv) + +static int rtl83xx_aux_mdio_cmd(struct realtek_aux_mdio_ctrl *ctrl, int addr, int regnum, + u32 rw_bit, u16 *data) +{ + unsigned int mask_volatile; + unsigned int cmd; + unsigned int run; + int err; + + cmd = rw_bit | RTL83XX_AUX_MDIO_EXEC; + cmd |= FIELD_PREP(RTL83XX_AUX_MDIO_PHY_ADDR, addr); + cmd |= FIELD_PREP(RTL83XX_AUX_MDIO_REG, regnum); + + mask_volatile = RTL83XX_AUX_MDIO_EXEC; + + if (rw_bit == RTL83XX_AUX_MDIO_WRITE) + cmd |= FIELD_PREP(RTL83XX_AUX_MDIO_DATA, *data); + else + mask_volatile |= RTL83XX_AUX_MDIO_DATA; + + err = regmap_write(ctrl->map, ctrl->cmd_reg, cmd); + if (err) + return err; + + err = regmap_read_poll_timeout(ctrl->map, ctrl->cmd_reg, run, (run != cmd), 3, 100); + + if ((run & ~mask_volatile) != (cmd & ~mask_volatile)) { + dev_err(ctrl->dev, "Command modified. Is offloading still active?"); + return -EIO; + } + + if (!err && (rw_bit == RTL83XX_AUX_MDIO_READ)) + *data = FIELD_GET(RTL83XX_AUX_MDIO_DATA, run); + + return err; +} + +static int rtl83xx_aux_mdio_read(struct mii_bus *bus, int addr, int regnum) +{ + struct realtek_aux_mdio_ctrl *ctrl = mii_bus_to_ctrl(bus); + u16 data; + int err; + + err = rtl83xx_aux_mdio_cmd(ctrl, addr, regnum, RTL83XX_AUX_MDIO_READ, &data); + + if (err) + return err; + else + return data; +} + +static int rtl83xx_aux_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val) +{ + struct realtek_aux_mdio_ctrl *ctrl = mii_bus_to_ctrl(bus); + + return rtl83xx_aux_mdio_cmd(ctrl, addr, regnum, RTL83XX_AUX_MDIO_WRITE, &val); +} + +static int realtek_aux_mdio_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct realtek_aux_mdio_ctrl *ctrl; + struct mii_bus *bus; + + bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*ctrl)); + if (!bus) + return -ENOMEM; + + ctrl = bus->priv; + ctrl->dev = &pdev->dev; + ctrl->cmd_reg = (unsigned int) device_get_match_data(ctrl->dev); + ctrl->map = syscon_node_to_regmap(np->parent); + if (IS_ERR(ctrl->map)) + return PTR_ERR(ctrl->map); + + bus->name = "RTL83xx auxiliary MDIO bus"; + snprintf(bus->id, MII_BUS_ID_SIZE, "rtl83xx-aux-mdio") ; + bus->parent = ctrl->dev; + bus->read = rtl83xx_aux_mdio_read; + bus->write = rtl83xx_aux_mdio_write; + /* Don't have interrupts */ + for (unsigned int i = 0; i < PHY_MAX_ADDR; i++) + bus->irq[i] = PHY_POLL; + + return devm_of_mdiobus_register(ctrl->dev, bus, np); +} + +static const struct of_device_id realtek_aux_mdio_of_match[] = { + { + .compatible = "realtek,rtl8380-aux-mdio", + .data = (void *) RTL8380_EXT_GPIO_INDIRECT_ACCESS, + }, + { + .compatible = "realtek,rtl8390-aux-mdio", + .data = (void *) RTL8390_EXT_GPIO_INDIRECT_ACCESS, + }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, realtek_aux_mdio_of_match); + +static struct platform_driver realtek_aux_mdio_driver = { + .driver = { + .name = "realtek-otto-aux-mdio", + .of_match_table = realtek_aux_mdio_of_match + }, + .probe = realtek_aux_mdio_probe, +}; +module_platform_driver(realtek_aux_mdio_driver); + +MODULE_AUTHOR("Sander Vanheule "); +MODULE_DESCRIPTION("Realtek RTL83xx auxiliary MDIO bus"); +MODULE_LICENSE("GPL v2");