1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23#include <linux/module.h>
24#include <linux/slab.h>
25#include <linux/interrupt.h>
26#include <linux/platform_device.h>
27#include <linux/gpio.h>
28#include <linux/platform_data/mdio-gpio.h>
29
30#include <linux/of_gpio.h>
31#include <linux/of_mdio.h>
32
33struct mdio_gpio_info {
34 struct mdiobb_ctrl ctrl;
35 int mdc, mdio, mdo;
36 int mdc_active_low, mdio_active_low, mdo_active_low;
37};
38
39static void *mdio_gpio_of_get_data(struct platform_device *pdev)
40{
41 struct device_node *np = pdev->dev.of_node;
42 struct mdio_gpio_platform_data *pdata;
43 enum of_gpio_flags flags;
44 int ret;
45
46 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
47 if (!pdata)
48 return NULL;
49
50 ret = of_get_gpio_flags(np, 0, &flags);
51 if (ret < 0)
52 return NULL;
53
54 pdata->mdc = ret;
55 pdata->mdc_active_low = flags & OF_GPIO_ACTIVE_LOW;
56
57 ret = of_get_gpio_flags(np, 1, &flags);
58 if (ret < 0)
59 return NULL;
60 pdata->mdio = ret;
61 pdata->mdio_active_low = flags & OF_GPIO_ACTIVE_LOW;
62
63 ret = of_get_gpio_flags(np, 2, &flags);
64 if (ret > 0) {
65 pdata->mdo = ret;
66 pdata->mdo_active_low = flags & OF_GPIO_ACTIVE_LOW;
67 }
68
69 return pdata;
70}
71
72static void mdio_dir(struct mdiobb_ctrl *ctrl, int dir)
73{
74 struct mdio_gpio_info *bitbang =
75 container_of(ctrl, struct mdio_gpio_info, ctrl);
76
77 if (bitbang->mdo) {
78
79
80
81
82
83 gpio_set_value_cansleep(bitbang->mdo,
84 1 ^ bitbang->mdo_active_low);
85 return;
86 }
87
88 if (dir)
89 gpio_direction_output(bitbang->mdio,
90 1 ^ bitbang->mdio_active_low);
91 else
92 gpio_direction_input(bitbang->mdio);
93}
94
95static int mdio_get(struct mdiobb_ctrl *ctrl)
96{
97 struct mdio_gpio_info *bitbang =
98 container_of(ctrl, struct mdio_gpio_info, ctrl);
99
100 return gpio_get_value_cansleep(bitbang->mdio) ^
101 bitbang->mdio_active_low;
102}
103
104static void mdio_set(struct mdiobb_ctrl *ctrl, int what)
105{
106 struct mdio_gpio_info *bitbang =
107 container_of(ctrl, struct mdio_gpio_info, ctrl);
108
109 if (bitbang->mdo)
110 gpio_set_value_cansleep(bitbang->mdo,
111 what ^ bitbang->mdo_active_low);
112 else
113 gpio_set_value_cansleep(bitbang->mdio,
114 what ^ bitbang->mdio_active_low);
115}
116
117static void mdc_set(struct mdiobb_ctrl *ctrl, int what)
118{
119 struct mdio_gpio_info *bitbang =
120 container_of(ctrl, struct mdio_gpio_info, ctrl);
121
122 gpio_set_value_cansleep(bitbang->mdc, what ^ bitbang->mdc_active_low);
123}
124
125static struct mdiobb_ops mdio_gpio_ops = {
126 .owner = THIS_MODULE,
127 .set_mdc = mdc_set,
128 .set_mdio_dir = mdio_dir,
129 .set_mdio_data = mdio_set,
130 .get_mdio_data = mdio_get,
131};
132
133static struct mii_bus *mdio_gpio_bus_init(struct device *dev,
134 struct mdio_gpio_platform_data *pdata,
135 int bus_id)
136{
137 struct mii_bus *new_bus;
138 struct mdio_gpio_info *bitbang;
139 int i;
140
141 bitbang = devm_kzalloc(dev, sizeof(*bitbang), GFP_KERNEL);
142 if (!bitbang)
143 goto out;
144
145 bitbang->ctrl.ops = &mdio_gpio_ops;
146 bitbang->ctrl.reset = pdata->reset;
147 bitbang->mdc = pdata->mdc;
148 bitbang->mdc_active_low = pdata->mdc_active_low;
149 bitbang->mdio = pdata->mdio;
150 bitbang->mdio_active_low = pdata->mdio_active_low;
151 bitbang->mdo = pdata->mdo;
152 bitbang->mdo_active_low = pdata->mdo_active_low;
153
154 new_bus = alloc_mdio_bitbang(&bitbang->ctrl);
155 if (!new_bus)
156 goto out;
157
158 new_bus->name = "GPIO Bitbanged MDIO",
159
160 new_bus->phy_mask = pdata->phy_mask;
161 new_bus->phy_ignore_ta_mask = pdata->phy_ignore_ta_mask;
162 memcpy(new_bus->irq, pdata->irqs, sizeof(new_bus->irq));
163 new_bus->parent = dev;
164
165 if (new_bus->phy_mask == ~0)
166 goto out_free_bus;
167
168 for (i = 0; i < PHY_MAX_ADDR; i++)
169 if (!new_bus->irq[i])
170 new_bus->irq[i] = PHY_POLL;
171
172 if (bus_id != -1)
173 snprintf(new_bus->id, MII_BUS_ID_SIZE, "gpio-%x", bus_id);
174 else
175 strncpy(new_bus->id, "gpio", MII_BUS_ID_SIZE);
176
177 if (devm_gpio_request(dev, bitbang->mdc, "mdc"))
178 goto out_free_bus;
179
180 if (devm_gpio_request(dev, bitbang->mdio, "mdio"))
181 goto out_free_bus;
182
183 if (bitbang->mdo) {
184 if (devm_gpio_request(dev, bitbang->mdo, "mdo"))
185 goto out_free_bus;
186 gpio_direction_output(bitbang->mdo, 1);
187 gpio_direction_input(bitbang->mdio);
188 }
189
190 gpio_direction_output(bitbang->mdc, 0);
191
192 dev_set_drvdata(dev, new_bus);
193
194 return new_bus;
195
196out_free_bus:
197 free_mdio_bitbang(new_bus);
198out:
199 return NULL;
200}
201
202static void mdio_gpio_bus_deinit(struct device *dev)
203{
204 struct mii_bus *bus = dev_get_drvdata(dev);
205
206 free_mdio_bitbang(bus);
207}
208
209static void mdio_gpio_bus_destroy(struct device *dev)
210{
211 struct mii_bus *bus = dev_get_drvdata(dev);
212
213 mdiobus_unregister(bus);
214 mdio_gpio_bus_deinit(dev);
215}
216
217static int mdio_gpio_probe(struct platform_device *pdev)
218{
219 struct mdio_gpio_platform_data *pdata;
220 struct mii_bus *new_bus;
221 int ret, bus_id;
222
223 if (pdev->dev.of_node) {
224 pdata = mdio_gpio_of_get_data(pdev);
225 bus_id = of_alias_get_id(pdev->dev.of_node, "mdio-gpio");
226 if (bus_id < 0) {
227 dev_warn(&pdev->dev, "failed to get alias id\n");
228 bus_id = 0;
229 }
230 } else {
231 pdata = dev_get_platdata(&pdev->dev);
232 bus_id = pdev->id;
233 }
234
235 if (!pdata)
236 return -ENODEV;
237
238 new_bus = mdio_gpio_bus_init(&pdev->dev, pdata, bus_id);
239 if (!new_bus)
240 return -ENODEV;
241
242 if (pdev->dev.of_node)
243 ret = of_mdiobus_register(new_bus, pdev->dev.of_node);
244 else
245 ret = mdiobus_register(new_bus);
246
247 if (ret)
248 mdio_gpio_bus_deinit(&pdev->dev);
249
250 return ret;
251}
252
253static int mdio_gpio_remove(struct platform_device *pdev)
254{
255 mdio_gpio_bus_destroy(&pdev->dev);
256
257 return 0;
258}
259
260static const struct of_device_id mdio_gpio_of_match[] = {
261 { .compatible = "virtual,mdio-gpio", },
262 { }
263};
264MODULE_DEVICE_TABLE(of, mdio_gpio_of_match);
265
266static struct platform_driver mdio_gpio_driver = {
267 .probe = mdio_gpio_probe,
268 .remove = mdio_gpio_remove,
269 .driver = {
270 .name = "mdio-gpio",
271 .of_match_table = mdio_gpio_of_match,
272 },
273};
274
275module_platform_driver(mdio_gpio_driver);
276
277MODULE_ALIAS("platform:mdio-gpio");
278MODULE_AUTHOR("Laurent Pinchart, Paulius Zaleckas");
279MODULE_LICENSE("GPL");
280MODULE_DESCRIPTION("Generic driver for MDIO bus emulation using GPIO");
281
