summaryrefslogtreecommitdiffstats
path: root/drivers/net/phy/mdio-gpio.c
blob: 8004acbef2c9e7867bbbae69595d41e80a3b0f7e (plain)
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
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
/*
 * GPIO based MDIO bitbang driver.
 * Supports OpenFirmware.
 *
 * Copyright (c) 2008 CSE Semaphore Belgium.
 *  by Laurent Pinchart <laurentp@cse-semaphore.com>
 *
 * Copyright (C) 2008, Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
 *
 * Based on earlier work by
 *
 * Copyright (c) 2003 Intracom S.A.
 *  by Pantelis Antoniou <panto@intracom.gr>
 *
 * 2005 (c) MontaVista Software, Inc.
 * Vitaly Bordug <vbordug@ru.mvista.com>
 *
 * This file is licensed under the terms of the GNU General Public License
 * version 2. This program is licensed "as is" without any warranty of any
 * kind, whether express or implied.
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/mdio-gpio.h>

#include <linux/of_gpio.h>
#include <linux/of_mdio.h>

struct mdio_gpio_info {
	struct mdiobb_ctrl ctrl;
	int mdc, mdio;
};

static void *mdio_gpio_of_get_data(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	struct mdio_gpio_platform_data *pdata;
	int ret;

	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return NULL;

	ret = of_get_gpio(np, 0);
	if (ret < 0)
		return NULL;

	pdata->mdc = ret;

	ret = of_get_gpio(np, 1);
	if (ret < 0)
		return NULL;
	pdata->mdio = ret;

	return pdata;
}

static void mdio_dir(struct mdiobb_ctrl *ctrl, int dir)
{
	struct mdio_gpio_info *bitbang =
		container_of(ctrl, struct mdio_gpio_info, ctrl);

	if (dir)
		gpio_direction_output(bitbang->mdio, 1);
	else
		gpio_direction_input(bitbang->mdio);
}

static int mdio_get(struct mdiobb_ctrl *ctrl)
{
	struct mdio_gpio_info *bitbang =
		container_of(ctrl, struct mdio_gpio_info, ctrl);

	return gpio_get_value(bitbang->mdio);
}

static void mdio_set(struct mdiobb_ctrl *ctrl, int what)
{
	struct mdio_gpio_info *bitbang =
		container_of(ctrl, struct mdio_gpio_info, ctrl);

	gpio_set_value(bitbang->mdio, what);
}

static void mdc_set(struct mdiobb_ctrl *ctrl, int what)
{
	struct mdio_gpio_info *bitbang =
		container_of(ctrl, struct mdio_gpio_info, ctrl);

	gpio_set_value(bitbang->mdc, what);
}

static struct mdiobb_ops mdio_gpio_ops = {
	.owner = THIS_MODULE,
	.set_mdc = mdc_set,
	.set_mdio_dir = mdio_dir,
	.set_mdio_data = mdio_set,
	.get_mdio_data = mdio_get,
};

static struct mii_bus *mdio_gpio_bus_init(struct device *dev,
					  struct mdio_gpio_platform_data *pdata,
					  int bus_id)
{
	struct mii_bus *new_bus;
	struct mdio_gpio_info *bitbang;
	int i;

	bitbang = kzalloc(sizeof(*bitbang), GFP_KERNEL);
	if (!bitbang)
		goto out;

	bitbang->ctrl.ops = &mdio_gpio_ops;
	bitbang->ctrl.reset = pdata->reset;
	bitbang->mdc = pdata->mdc;
	bitbang->mdio = pdata->mdio;

	new_bus = alloc_mdio_bitbang(&bitbang->ctrl);
	if (!new_bus)
		goto out_free_bitbang;

	new_bus->name = "GPIO Bitbanged MDIO",

	new_bus->phy_mask = pdata->phy_mask;
	new_bus->irq = pdata->irqs;
	new_bus->parent = dev;

	if (new_bus->phy_mask == ~0)
		goto out_free_bus;

	for (i = 0; i < PHY_MAX_ADDR; i++)
		if (!new_bus->irq[i])
			new_bus->irq[i] = PHY_POLL;

	snprintf(new_bus->id, MII_BUS_ID_SIZE, "gpio-%x", bus_id);

	if (gpio_request(bitbang->mdc, "mdc"))
		goto out_free_bus;

	if (gpio_request(bitbang->mdio, "mdio"))
		goto out_free_mdc;

	gpio_direction_output(bitbang->mdc, 0);

	dev_set_drvdata(dev, new_bus);

	return new_bus;

out_free_mdc:
	gpio_free(bitbang->mdc);
out_free_bus:
	free_mdio_bitbang(new_bus);
out_free_bitbang:
	kfree(bitbang);
out:
	return NULL;
}

static void mdio_gpio_bus_deinit(struct device *dev)
{
	struct mii_bus *bus = dev_get_drvdata(dev);
	struct mdio_gpio_info *bitbang = bus->priv;

	dev_set_drvdata(dev, NULL);
	gpio_free(bitbang->mdio);
	gpio_free(bitbang->mdc);
	free_mdio_bitbang(bus);
	kfree(bitbang);
}

static void mdio_gpio_bus_destroy(struct device *dev)
{
	struct mii_bus *bus = dev_get_drvdata(dev);

	mdiobus_unregister(bus);
	mdio_gpio_bus_deinit(dev);
}

static int mdio_gpio_probe(struct platform_device *pdev)
{
	struct mdio_gpio_platform_data *pdata;
	struct mii_bus *new_bus;
	int ret, bus_id;

	if (pdev->dev.of_node) {
		pdata = mdio_gpio_of_get_data(pdev);
		bus_id = of_alias_get_id(pdev->dev.of_node, "mdio-gpio");
	} else {
		pdata = dev_get_platdata(&pdev->dev);
		bus_id = pdev->id;
	}

	if (!pdata)
		return -ENODEV;

	new_bus = mdio_gpio_bus_init(&pdev->dev, pdata, bus_id);
	if (!new_bus)
		return -ENODEV;

	if (pdev->dev.of_node)
		ret = of_mdiobus_register(new_bus, pdev->dev.of_node);
	else
		ret = mdiobus_register(new_bus);

	if (ret)
		mdio_gpio_bus_deinit(&pdev->dev);

	return ret;
}

static int mdio_gpio_remove(struct platform_device *pdev)
{
	mdio_gpio_bus_destroy(&pdev->dev);

	return 0;
}

static struct of_device_id mdio_gpio_of_match[] = {
	{ .compatible = "virtual,mdio-gpio", },
	{ /* sentinel */ }
};

static struct platform_driver mdio_gpio_driver = {
	.probe = mdio_gpio_probe,
	.remove = mdio_gpio_remove,
	.driver		= {
		.name	= "mdio-gpio",
		.owner	= THIS_MODULE,
		.of_match_table = mdio_gpio_of_match,
	},
};

module_platform_driver(mdio_gpio_driver);

MODULE_ALIAS("platform:mdio-gpio");
MODULE_AUTHOR("Laurent Pinchart, Paulius Zaleckas");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Generic driver for MDIO bus emulation using GPIO");