--- /dev/null
+From c7ddb74c981c1a29bad82d555d08724aca93b687 Mon Sep 17 00:00:00 2001
+From: Sander Vanheule <sander@svanheule.net>
+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 <sander@svanheule.net>
+---
+ 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 <linux/mfd/core.h>
++#include <linux/mfd/syscon.h>
++#include <linux/module.h>
++#include <linux/of.h>
++#include <linux/of_mdio.h>
++#include <linux/of_platform.h>
++#include <linux/phy.h>
++#include <linux/platform_device.h>
++#include <linux/regmap.h>
++
++#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 <sander@svanheule.net>");
++MODULE_DESCRIPTION("Realtek RTL83xx auxiliary MDIO bus");
++MODULE_LICENSE("GPL v2");
projects / openwrt / staging / svanheule.git / commitdiff