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12#include <linux/delay.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/mutex.h>
16#include <linux/of_address.h>
17#include <linux/of_mdio.h>
18#include <linux/phy.h>
19#include <linux/platform_device.h>
20#include <linux/regulator/consumer.h>
21
22#define EMAC_MAC_MCMD_REG (0x00)
23#define EMAC_MAC_MADR_REG (0x04)
24#define EMAC_MAC_MWTD_REG (0x08)
25#define EMAC_MAC_MRDD_REG (0x0c)
26#define EMAC_MAC_MIND_REG (0x10)
27#define EMAC_MAC_SSRR_REG (0x14)
28
29#define MDIO_TIMEOUT (msecs_to_jiffies(100))
30
31struct sun4i_mdio_data {
32 void __iomem *membase;
33 struct regulator *regulator;
34};
35
36static int sun4i_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
37{
38 struct sun4i_mdio_data *data = bus->priv;
39 unsigned long timeout_jiffies;
40 int value;
41
42
43 writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
44
45 writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
46
47
48 timeout_jiffies = jiffies + MDIO_TIMEOUT;
49 while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
50 if (time_is_before_jiffies(timeout_jiffies))
51 return -ETIMEDOUT;
52 msleep(1);
53 }
54
55
56 writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
57
58 value = readl(data->membase + EMAC_MAC_MRDD_REG);
59
60 return value;
61}
62
63static int sun4i_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
64 u16 value)
65{
66 struct sun4i_mdio_data *data = bus->priv;
67 unsigned long timeout_jiffies;
68
69
70 writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
71
72 writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
73
74
75 timeout_jiffies = jiffies + MDIO_TIMEOUT;
76 while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
77 if (time_is_before_jiffies(timeout_jiffies))
78 return -ETIMEDOUT;
79 msleep(1);
80 }
81
82
83 writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
84
85 writel(value, data->membase + EMAC_MAC_MWTD_REG);
86
87 return 0;
88}
89
90static int sun4i_mdio_probe(struct platform_device *pdev)
91{
92 struct device_node *np = pdev->dev.of_node;
93 struct mii_bus *bus;
94 struct sun4i_mdio_data *data;
95 int ret;
96
97 bus = mdiobus_alloc_size(sizeof(*data));
98 if (!bus)
99 return -ENOMEM;
100
101 bus->name = "sun4i_mii_bus";
102 bus->read = &sun4i_mdio_read;
103 bus->write = &sun4i_mdio_write;
104 snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
105 bus->parent = &pdev->dev;
106
107 data = bus->priv;
108 data->membase = devm_platform_ioremap_resource(pdev, 0);
109 if (IS_ERR(data->membase)) {
110 ret = PTR_ERR(data->membase);
111 goto err_out_free_mdiobus;
112 }
113
114 data->regulator = devm_regulator_get(&pdev->dev, "phy");
115 if (IS_ERR(data->regulator)) {
116 if (PTR_ERR(data->regulator) == -EPROBE_DEFER) {
117 ret = -EPROBE_DEFER;
118 goto err_out_free_mdiobus;
119 }
120
121 dev_info(&pdev->dev, "no regulator found\n");
122 data->regulator = NULL;
123 } else {
124 ret = regulator_enable(data->regulator);
125 if (ret)
126 goto err_out_free_mdiobus;
127 }
128
129 ret = of_mdiobus_register(bus, np);
130 if (ret < 0)
131 goto err_out_disable_regulator;
132
133 platform_set_drvdata(pdev, bus);
134
135 return 0;
136
137err_out_disable_regulator:
138 if (data->regulator)
139 regulator_disable(data->regulator);
140err_out_free_mdiobus:
141 mdiobus_free(bus);
142 return ret;
143}
144
145static int sun4i_mdio_remove(struct platform_device *pdev)
146{
147 struct mii_bus *bus = platform_get_drvdata(pdev);
148 struct sun4i_mdio_data *data = bus->priv;
149
150 mdiobus_unregister(bus);
151 if (data->regulator)
152 regulator_disable(data->regulator);
153 mdiobus_free(bus);
154
155 return 0;
156}
157
158static const struct of_device_id sun4i_mdio_dt_ids[] = {
159 { .compatible = "allwinner,sun4i-a10-mdio" },
160
161
162 { .compatible = "allwinner,sun4i-mdio" },
163 { }
164};
165MODULE_DEVICE_TABLE(of, sun4i_mdio_dt_ids);
166
167static struct platform_driver sun4i_mdio_driver = {
168 .probe = sun4i_mdio_probe,
169 .remove = sun4i_mdio_remove,
170 .driver = {
171 .name = "sun4i-mdio",
172 .of_match_table = sun4i_mdio_dt_ids,
173 },
174};
175
176module_platform_driver(sun4i_mdio_driver);
177
178MODULE_DESCRIPTION("Allwinner EMAC MDIO interface driver");
179MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
180MODULE_LICENSE("GPL v2");
181
