1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * Hisilicon Fast Ethernet MDIO Bus Driver |
4 | * |
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 0x00 |
17 | #define MDIO_RO_DATA 0x04 |
18 | #define MDIO_WRITE BIT(13) |
19 | #define MDIO_RW_FINISH BIT(15) |
20 | #define BIT_PHY_ADDR_OFFSET 8 |
21 | #define BIT_WR_DATA_OFFSET 16 |
22 | |
23 | struct hisi_femac_mdio_data { |
24 | struct clk *clk; |
25 | void __iomem *membase; |
26 | }; |
27 | |
28 | static 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 | |
36 | static 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(val: (mii_id << BIT_PHY_ADDR_OFFSET) | regnum, |
46 | addr: data->membase + MDIO_RWCTRL); |
47 | |
48 | ret = hisi_femac_mdio_wait_ready(data); |
49 | if (ret) |
50 | return ret; |
51 | |
52 | return readl(addr: data->membase + MDIO_RO_DATA) & 0xFFFF; |
53 | } |
54 | |
55 | static 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 | addr: data->membase + MDIO_RWCTRL); |
68 | |
69 | return hisi_femac_mdio_wait_ready(data); |
70 | } |
71 | |
72 | static 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(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(buf: bus->id, MII_BUS_ID_SIZE, fmt: "%s" , pdev->name); |
87 | bus->parent = &pdev->dev; |
88 | |
89 | data = bus->priv; |
90 | data->membase = devm_platform_ioremap_resource(pdev, index: 0); |
91 | if (IS_ERR(ptr: data->membase)) { |
92 | ret = PTR_ERR(ptr: data->membase); |
93 | goto err_out_free_mdiobus; |
94 | } |
95 | |
96 | data->clk = devm_clk_get(dev: &pdev->dev, NULL); |
97 | if (IS_ERR(ptr: data->clk)) { |
98 | ret = PTR_ERR(ptr: data->clk); |
99 | goto err_out_free_mdiobus; |
100 | } |
101 | |
102 | ret = clk_prepare_enable(clk: data->clk); |
103 | if (ret) |
104 | goto err_out_free_mdiobus; |
105 | |
106 | ret = of_mdiobus_register(mdio: bus, np); |
107 | if (ret) |
108 | goto err_out_disable_clk; |
109 | |
110 | platform_set_drvdata(pdev, data: bus); |
111 | |
112 | return 0; |
113 | |
114 | err_out_disable_clk: |
115 | clk_disable_unprepare(clk: data->clk); |
116 | err_out_free_mdiobus: |
117 | mdiobus_free(bus); |
118 | return ret; |
119 | } |
120 | |
121 | static 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(clk: data->clk); |
128 | mdiobus_free(bus); |
129 | } |
130 | |
131 | static const struct of_device_id hisi_femac_mdio_dt_ids[] = { |
132 | { .compatible = "hisilicon,hisi-femac-mdio" }, |
133 | { } |
134 | }; |
135 | MODULE_DEVICE_TABLE(of, hisi_femac_mdio_dt_ids); |
136 | |
137 | static 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 | |
146 | module_platform_driver(hisi_femac_mdio_driver); |
147 | |
148 | MODULE_DESCRIPTION("Hisilicon Fast Ethernet MAC MDIO interface driver" ); |
149 | MODULE_AUTHOR("Dongpo Li <lidongpo@hisilicon.com>" ); |
150 | MODULE_LICENSE("GPL" ); |
151 | |