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15#include <linux/delay.h>
16#include <linux/init.h>
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <linux/mutex.h>
20#include <linux/of_address.h>
21#include <linux/of_mdio.h>
22#include <linux/phy.h>
23#include <linux/platform_device.h>
24#include <linux/regulator/consumer.h>
25
26#define EMAC_MAC_MCMD_REG (0x00)
27#define EMAC_MAC_MADR_REG (0x04)
28#define EMAC_MAC_MWTD_REG (0x08)
29#define EMAC_MAC_MRDD_REG (0x0c)
30#define EMAC_MAC_MIND_REG (0x10)
31#define EMAC_MAC_SSRR_REG (0x14)
32
33#define MDIO_TIMEOUT (msecs_to_jiffies(100))
34
35struct sun4i_mdio_data {
36 void __iomem *membase;
37 struct regulator *regulator;
38};
39
40static int sun4i_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
41{
42 struct sun4i_mdio_data *data = bus->priv;
43 unsigned long timeout_jiffies;
44 int value;
45
46
47 writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
48
49 writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
50
51
52 timeout_jiffies = jiffies + MDIO_TIMEOUT;
53 while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
54 if (time_is_before_jiffies(timeout_jiffies))
55 return -ETIMEDOUT;
56 msleep(1);
57 }
58
59
60 writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
61
62 value = readl(data->membase + EMAC_MAC_MRDD_REG);
63
64 return value;
65}
66
67static int sun4i_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
68 u16 value)
69{
70 struct sun4i_mdio_data *data = bus->priv;
71 unsigned long timeout_jiffies;
72
73
74 writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
75
76 writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
77
78
79 timeout_jiffies = jiffies + MDIO_TIMEOUT;
80 while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
81 if (time_is_before_jiffies(timeout_jiffies))
82 return -ETIMEDOUT;
83 msleep(1);
84 }
85
86
87 writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
88
89 writel(value, data->membase + EMAC_MAC_MWTD_REG);
90
91 return 0;
92}
93
94static int sun4i_mdio_reset(struct mii_bus *bus)
95{
96 return 0;
97}
98
99static int sun4i_mdio_probe(struct platform_device *pdev)
100{
101 struct device_node *np = pdev->dev.of_node;
102 struct mii_bus *bus;
103 struct sun4i_mdio_data *data;
104 int ret, i;
105
106 bus = mdiobus_alloc_size(sizeof(*data));
107 if (!bus)
108 return -ENOMEM;
109
110 bus->name = "sun4i_mii_bus";
111 bus->read = &sun4i_mdio_read;
112 bus->write = &sun4i_mdio_write;
113 bus->reset = &sun4i_mdio_reset;
114 snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
115 bus->parent = &pdev->dev;
116
117 bus->irq = kmalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
118 if (!bus->irq) {
119 ret = -ENOMEM;
120 goto err_out_free_mdiobus;
121 }
122
123 for (i = 0; i < PHY_MAX_ADDR; i++)
124 bus->irq[i] = PHY_POLL;
125
126 data = bus->priv;
127 data->membase = of_iomap(np, 0);
128 if (!data->membase) {
129 ret = -ENOMEM;
130 goto err_out_free_mdio_irq;
131 }
132
133 data->regulator = devm_regulator_get(&pdev->dev, "phy");
134 if (IS_ERR(data->regulator)) {
135 if (PTR_ERR(data->regulator) == -EPROBE_DEFER)
136 return -EPROBE_DEFER;
137
138 dev_info(&pdev->dev, "no regulator found\n");
139 } else {
140 ret = regulator_enable(data->regulator);
141 if (ret)
142 goto err_out_free_mdio_irq;
143 }
144
145 ret = of_mdiobus_register(bus, np);
146 if (ret < 0)
147 goto err_out_disable_regulator;
148
149 platform_set_drvdata(pdev, bus);
150
151 return 0;
152
153err_out_disable_regulator:
154 regulator_disable(data->regulator);
155err_out_free_mdio_irq:
156 kfree(bus->irq);
157err_out_free_mdiobus:
158 mdiobus_free(bus);
159 return ret;
160}
161
162static int sun4i_mdio_remove(struct platform_device *pdev)
163{
164 struct mii_bus *bus = platform_get_drvdata(pdev);
165
166 mdiobus_unregister(bus);
167 kfree(bus->irq);
168 mdiobus_free(bus);
169
170 return 0;
171}
172
173static const struct of_device_id sun4i_mdio_dt_ids[] = {
174 { .compatible = "allwinner,sun4i-mdio" },
175 { }
176};
177MODULE_DEVICE_TABLE(of, sun4i_mdio_dt_ids);
178
179static struct platform_driver sun4i_mdio_driver = {
180 .probe = sun4i_mdio_probe,
181 .remove = sun4i_mdio_remove,
182 .driver = {
183 .name = "sun4i-mdio",
184 .of_match_table = sun4i_mdio_dt_ids,
185 },
186};
187
188module_platform_driver(sun4i_mdio_driver);
189
190MODULE_DESCRIPTION("Allwinner EMAC MDIO interface driver");
191MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
192MODULE_LICENSE("GPL");
193
