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8#include <linux/delay.h>
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/of_mdio.h>
12#include <linux/of_address.h>
13#include <linux/platform_device.h>
14#include <linux/regmap.h>
15
16
17#define MII_ADDR_REG_ADDR 0x10
18#define MII_BUSY BIT(0)
19#define MII_WRITE BIT(1)
20#define MII_CLKRANGE(x) ((x) << 2)
21#define MII_CLKRANGE_60_100M MII_CLKRANGE(0)
22#define MII_CLKRANGE_100_150M MII_CLKRANGE(1)
23#define MII_CLKRANGE_20_35M MII_CLKRANGE(2)
24#define MII_CLKRANGE_35_60M MII_CLKRANGE(3)
25#define MII_CLKRANGE_150_250M MII_CLKRANGE(4)
26#define MII_CLKRANGE_250_300M MII_CLKRANGE(5)
27#define MII_CLKRANGE_MASK GENMASK(4, 2)
28#define MII_REG_SHIFT 6
29#define MII_REG_MASK GENMASK(10, 6)
30#define MII_ADDR_SHIFT 11
31#define MII_ADDR_MASK GENMASK(15, 11)
32
33#define MII_DATA_REG_ADDR 0x14
34
35#define MII_MDIO_DELAY_USEC (1000)
36#define MII_MDIO_RETRY_MSEC (10)
37
38struct ipq8064_mdio {
39 struct regmap *base;
40};
41
42static int
43ipq8064_mdio_wait_busy(struct ipq8064_mdio *priv)
44{
45 u32 busy;
46
47 return regmap_read_poll_timeout(priv->base, MII_ADDR_REG_ADDR, busy,
48 !(busy & MII_BUSY), MII_MDIO_DELAY_USEC,
49 MII_MDIO_RETRY_MSEC * USEC_PER_MSEC);
50}
51
52static int
53ipq8064_mdio_read(struct mii_bus *bus, int phy_addr, int reg_offset)
54{
55 u32 miiaddr = MII_BUSY | MII_CLKRANGE_250_300M;
56 struct ipq8064_mdio *priv = bus->priv;
57 u32 ret_val;
58 int err;
59
60
61 if (reg_offset & MII_ADDR_C45)
62 return -EOPNOTSUPP;
63
64 miiaddr |= ((phy_addr << MII_ADDR_SHIFT) & MII_ADDR_MASK) |
65 ((reg_offset << MII_REG_SHIFT) & MII_REG_MASK);
66
67 regmap_write(priv->base, MII_ADDR_REG_ADDR, miiaddr);
68 usleep_range(10, 13);
69
70 err = ipq8064_mdio_wait_busy(priv);
71 if (err)
72 return err;
73
74 regmap_read(priv->base, MII_DATA_REG_ADDR, &ret_val);
75 return (int)ret_val;
76}
77
78static int
79ipq8064_mdio_write(struct mii_bus *bus, int phy_addr, int reg_offset, u16 data)
80{
81 u32 miiaddr = MII_WRITE | MII_BUSY | MII_CLKRANGE_250_300M;
82 struct ipq8064_mdio *priv = bus->priv;
83
84
85 if (reg_offset & MII_ADDR_C45)
86 return -EOPNOTSUPP;
87
88 regmap_write(priv->base, MII_DATA_REG_ADDR, data);
89
90 miiaddr |= ((phy_addr << MII_ADDR_SHIFT) & MII_ADDR_MASK) |
91 ((reg_offset << MII_REG_SHIFT) & MII_REG_MASK);
92
93 regmap_write(priv->base, MII_ADDR_REG_ADDR, miiaddr);
94
95
96
97
98 if (reg_offset == 31)
99 usleep_range(30, 43);
100 else
101 usleep_range(10, 13);
102
103 return ipq8064_mdio_wait_busy(priv);
104}
105
106static const struct regmap_config ipq8064_mdio_regmap_config = {
107 .reg_bits = 32,
108 .reg_stride = 4,
109 .val_bits = 32,
110 .can_multi_write = false,
111
112 .disable_locking = true,
113
114 .cache_type = REGCACHE_NONE,
115};
116
117static int
118ipq8064_mdio_probe(struct platform_device *pdev)
119{
120 struct device_node *np = pdev->dev.of_node;
121 struct ipq8064_mdio *priv;
122 struct resource res;
123 struct mii_bus *bus;
124 void __iomem *base;
125 int ret;
126
127 if (of_address_to_resource(np, 0, &res))
128 return -ENOMEM;
129
130 base = ioremap(res.start, resource_size(&res));
131 if (!base)
132 return -ENOMEM;
133
134 bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));
135 if (!bus)
136 return -ENOMEM;
137
138 bus->name = "ipq8064_mdio_bus";
139 bus->read = ipq8064_mdio_read;
140 bus->write = ipq8064_mdio_write;
141 snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
142 bus->parent = &pdev->dev;
143
144 priv = bus->priv;
145 priv->base = devm_regmap_init_mmio(&pdev->dev, base,
146 &ipq8064_mdio_regmap_config);
147 if (IS_ERR(priv->base))
148 return PTR_ERR(priv->base);
149
150 ret = of_mdiobus_register(bus, np);
151 if (ret)
152 return ret;
153
154 platform_set_drvdata(pdev, bus);
155 return 0;
156}
157
158static int
159ipq8064_mdio_remove(struct platform_device *pdev)
160{
161 struct mii_bus *bus = platform_get_drvdata(pdev);
162
163 mdiobus_unregister(bus);
164
165 return 0;
166}
167
168static const struct of_device_id ipq8064_mdio_dt_ids[] = {
169 { .compatible = "qcom,ipq8064-mdio" },
170 { }
171};
172MODULE_DEVICE_TABLE(of, ipq8064_mdio_dt_ids);
173
174static struct platform_driver ipq8064_mdio_driver = {
175 .probe = ipq8064_mdio_probe,
176 .remove = ipq8064_mdio_remove,
177 .driver = {
178 .name = "ipq8064-mdio",
179 .of_match_table = ipq8064_mdio_dt_ids,
180 },
181};
182
183module_platform_driver(ipq8064_mdio_driver);
184
185MODULE_DESCRIPTION("Qualcomm IPQ8064 MDIO interface driver");
186MODULE_AUTHOR("Christian Lamparter <chunkeey@gmail.com>");
187MODULE_AUTHOR("Ansuel Smith <ansuelsmth@gmail.com>");
188MODULE_LICENSE("GPL");
189
