aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/net/phy/mdio-sun4i.c
blob: f798de3276dce4c5cc33eb11018522e8829ee6a1 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
// SPDX-License-Identifier: GPL-2.0
/*
 * Allwinner EMAC MDIO interface driver
 *
 * Copyright 2012-2013 Stefan Roese <sr@denx.de>
 * Copyright 2013 Maxime Ripard <maxime.ripard@free-electrons.com>
 *
 * Based on the Linux driver provided by Allwinner:
 * Copyright (C) 1997  Sten Wang
 */

#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of_address.h>
#include <linux/of_mdio.h>
#include <linux/phy.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>

#define EMAC_MAC_MCMD_REG	(0x00)
#define EMAC_MAC_MADR_REG	(0x04)
#define EMAC_MAC_MWTD_REG	(0x08)
#define EMAC_MAC_MRDD_REG	(0x0c)
#define EMAC_MAC_MIND_REG	(0x10)
#define EMAC_MAC_SSRR_REG	(0x14)

#define MDIO_TIMEOUT		(msecs_to_jiffies(100))

struct sun4i_mdio_data {
	void __iomem		*membase;
	struct regulator	*regulator;
};

static int sun4i_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
{
	struct sun4i_mdio_data *data = bus->priv;
	unsigned long timeout_jiffies;
	int value;

	/* issue the phy address and reg */
	writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
	/* pull up the phy io line */
	writel(0x1, data->membase + EMAC_MAC_MCMD_REG);

	/* Wait read complete */
	timeout_jiffies = jiffies + MDIO_TIMEOUT;
	while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
		if (time_is_before_jiffies(timeout_jiffies))
			return -ETIMEDOUT;
		msleep(1);
	}

	/* push down the phy io line */
	writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
	/* and read data */
	value = readl(data->membase + EMAC_MAC_MRDD_REG);

	return value;
}

static int sun4i_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
			    u16 value)
{
	struct sun4i_mdio_data *data = bus->priv;
	unsigned long timeout_jiffies;

	/* issue the phy address and reg */
	writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
	/* pull up the phy io line */
	writel(0x1, data->membase + EMAC_MAC_MCMD_REG);

	/* Wait read complete */
	timeout_jiffies = jiffies + MDIO_TIMEOUT;
	while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
		if (time_is_before_jiffies(timeout_jiffies))
			return -ETIMEDOUT;
		msleep(1);
	}

	/* push down the phy io line */
	writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
	/* and write data */
	writel(value, data->membase + EMAC_MAC_MWTD_REG);

	return 0;
}

static int sun4i_mdio_probe(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	struct mii_bus *bus;
	struct sun4i_mdio_data *data;
	int ret;

	bus = mdiobus_alloc_size(sizeof(*data));
	if (!bus)
		return -ENOMEM;

	bus->name = "sun4i_mii_bus";
	bus->read = &sun4i_mdio_read;
	bus->write = &sun4i_mdio_write;
	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
	bus->parent = &pdev->dev;

	data = bus->priv;
	data->membase = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(data->membase)) {
		ret = PTR_ERR(data->membase);
		goto err_out_free_mdiobus;
	}

	data->regulator = devm_regulator_get(&pdev->dev, "phy");
	if (IS_ERR(data->regulator)) {
		if (PTR_ERR(data->regulator) == -EPROBE_DEFER) {
			ret = -EPROBE_DEFER;
			goto err_out_free_mdiobus;
		}

		dev_info(&pdev->dev, "no regulator found\n");
		data->regulator = NULL;
	} else {
		ret = regulator_enable(data->regulator);
		if (ret)
			goto err_out_free_mdiobus;
	}

	ret = of_mdiobus_register(bus, np);
	if (ret < 0)
		goto err_out_disable_regulator;

	platform_set_drvdata(pdev, bus);

	return 0;

err_out_disable_regulator:
	if (data->regulator)
		regulator_disable(data->regulator);
err_out_free_mdiobus:
	mdiobus_free(bus);
	return ret;
}

static int sun4i_mdio_remove(struct platform_device *pdev)
{
	struct mii_bus *bus = platform_get_drvdata(pdev);
	struct sun4i_mdio_data *data = bus->priv;

	mdiobus_unregister(bus);
	if (data->regulator)
		regulator_disable(data->regulator);
	mdiobus_free(bus);

	return 0;
}

static const struct of_device_id sun4i_mdio_dt_ids[] = {
	{ .compatible = "allwinner,sun4i-a10-mdio" },

	/* Deprecated */
	{ .compatible = "allwinner,sun4i-mdio" },
	{ }
};
MODULE_DEVICE_TABLE(of, sun4i_mdio_dt_ids);

static struct platform_driver sun4i_mdio_driver = {
	.probe = sun4i_mdio_probe,
	.remove = sun4i_mdio_remove,
	.driver = {
		.name = "sun4i-mdio",
		.of_match_table = sun4i_mdio_dt_ids,
	},
};

module_platform_driver(sun4i_mdio_driver);

MODULE_DESCRIPTION("Allwinner EMAC MDIO interface driver");
MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
MODULE_LICENSE("GPL v2");