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1// SPDX-License-Identifier: GPL-2.0+2/*3 * Hisilicon Fast Ethernet MDIO Bus Driver4 *5 * Copyright (c) 2016 HiSilicon Technologies Co., Ltd.6 */7 8#include <linux/clk.h>9#include <linux/iopoll.h>10#include <linux/kernel.h>11#include <linux/module.h>12#include <linux/of_address.h>13#include <linux/of_mdio.h>14#include <linux/platform_device.h>15 16#define MDIO_RWCTRL 0x0017#define MDIO_RO_DATA 0x0418#define MDIO_WRITE BIT(13)19#define MDIO_RW_FINISH BIT(15)20#define BIT_PHY_ADDR_OFFSET 821#define BIT_WR_DATA_OFFSET 1622 23struct hisi_femac_mdio_data {24 struct clk *clk;25 void __iomem *membase;26};27 28static int hisi_femac_mdio_wait_ready(struct hisi_femac_mdio_data *data)29{30 u32 val;31 32 return readl_poll_timeout(data->membase + MDIO_RWCTRL,33 val, val & MDIO_RW_FINISH, 20, 10000);34}35 36static int hisi_femac_mdio_read(struct mii_bus *bus, int mii_id, int regnum)37{38 struct hisi_femac_mdio_data *data = bus->priv;39 int ret;40 41 ret = hisi_femac_mdio_wait_ready(data);42 if (ret)43 return ret;44 45 writel((mii_id << BIT_PHY_ADDR_OFFSET) | regnum,46 data->membase + MDIO_RWCTRL);47 48 ret = hisi_femac_mdio_wait_ready(data);49 if (ret)50 return ret;51 52 return readl(data->membase + MDIO_RO_DATA) & 0xFFFF;53}54 55static int hisi_femac_mdio_write(struct mii_bus *bus, int mii_id, int regnum,56 u16 value)57{58 struct hisi_femac_mdio_data *data = bus->priv;59 int ret;60 61 ret = hisi_femac_mdio_wait_ready(data);62 if (ret)63 return ret;64 65 writel(MDIO_WRITE | (value << BIT_WR_DATA_OFFSET) |66 (mii_id << BIT_PHY_ADDR_OFFSET) | regnum,67 data->membase + MDIO_RWCTRL);68 69 return hisi_femac_mdio_wait_ready(data);70}71 72static int hisi_femac_mdio_probe(struct platform_device *pdev)73{74 struct device_node *np = pdev->dev.of_node;75 struct mii_bus *bus;76 struct hisi_femac_mdio_data *data;77 int ret;78 79 bus = mdiobus_alloc_size(sizeof(*data));80 if (!bus)81 return -ENOMEM;82 83 bus->name = "hisi_femac_mii_bus";84 bus->read = &hisi_femac_mdio_read;85 bus->write = &hisi_femac_mdio_write;86 snprintf(bus->id, MII_BUS_ID_SIZE, "%s", pdev->name);87 bus->parent = &pdev->dev;88 89 data = bus->priv;90 data->membase = devm_platform_ioremap_resource(pdev, 0);91 if (IS_ERR(data->membase)) {92 ret = PTR_ERR(data->membase);93 goto err_out_free_mdiobus;94 }95 96 data->clk = devm_clk_get(&pdev->dev, NULL);97 if (IS_ERR(data->clk)) {98 ret = PTR_ERR(data->clk);99 goto err_out_free_mdiobus;100 }101 102 ret = clk_prepare_enable(data->clk);103 if (ret)104 goto err_out_free_mdiobus;105 106 ret = of_mdiobus_register(bus, np);107 if (ret)108 goto err_out_disable_clk;109 110 platform_set_drvdata(pdev, bus);111 112 return 0;113 114err_out_disable_clk:115 clk_disable_unprepare(data->clk);116err_out_free_mdiobus:117 mdiobus_free(bus);118 return ret;119}120 121static void hisi_femac_mdio_remove(struct platform_device *pdev)122{123 struct mii_bus *bus = platform_get_drvdata(pdev);124 struct hisi_femac_mdio_data *data = bus->priv;125 126 mdiobus_unregister(bus);127 clk_disable_unprepare(data->clk);128 mdiobus_free(bus);129}130 131static const struct of_device_id hisi_femac_mdio_dt_ids[] = {132 { .compatible = "hisilicon,hisi-femac-mdio" },133 { }134};135MODULE_DEVICE_TABLE(of, hisi_femac_mdio_dt_ids);136 137static struct platform_driver hisi_femac_mdio_driver = {138 .probe = hisi_femac_mdio_probe,139 .remove_new = hisi_femac_mdio_remove,140 .driver = {141 .name = "hisi-femac-mdio",142 .of_match_table = hisi_femac_mdio_dt_ids,143 },144};145 146module_platform_driver(hisi_femac_mdio_driver);147 148MODULE_DESCRIPTION("Hisilicon Fast Ethernet MAC MDIO interface driver");149MODULE_AUTHOR("Dongpo Li <lidongpo@hisilicon.com>");150MODULE_LICENSE("GPL");151