1 /*
2 * GPIO based MDIO bitbang driver.
3 * Supports OpenFirmware.
4 *
5 * Copyright (c) 2008 CSE Semaphore Belgium.
6 * by Laurent Pinchart <laurentp@cse-semaphore.com>
7 *
8 * Copyright (C) 2008, Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
9 *
10 * Based on earlier work by
11 *
12 * Copyright (c) 2003 Intracom S.A.
13 * by Pantelis Antoniou <panto@intracom.gr>
14 *
15 * 2005 (c) MontaVista Software, Inc.
16 * Vitaly Bordug <vbordug@ru.mvista.com>
17 *
18 * This file is licensed under the terms of the GNU General Public License
19 * version 2. This program is licensed "as is" without any warranty of any
20 * kind, whether express or implied.
21 */
22
23 #include <linux/module.h>
24 #include <linux/slab.h>
25 #include <linux/init.h>
26 #include <linux/interrupt.h>
27 #include <linux/platform_device.h>
28 #include <linux/gpio.h>
29 #include <linux/mdio-gpio.h>
30
31 #ifdef CONFIG_OF_GPIO
32 #include <linux/of_gpio.h>
33 #include <linux/of_mdio.h>
34 #include <linux/of_platform.h>
35 #endif
36
37 struct mdio_gpio_info {
38 struct mdiobb_ctrl ctrl;
39 int mdc, mdio;
40 };
41
mdio_dir(struct mdiobb_ctrl * ctrl,int dir)42 static void mdio_dir(struct mdiobb_ctrl *ctrl, int dir)
43 {
44 struct mdio_gpio_info *bitbang =
45 container_of(ctrl, struct mdio_gpio_info, ctrl);
46
47 if (dir)
48 gpio_direction_output(bitbang->mdio, 1);
49 else
50 gpio_direction_input(bitbang->mdio);
51 }
52
mdio_get(struct mdiobb_ctrl * ctrl)53 static int mdio_get(struct mdiobb_ctrl *ctrl)
54 {
55 struct mdio_gpio_info *bitbang =
56 container_of(ctrl, struct mdio_gpio_info, ctrl);
57
58 return gpio_get_value(bitbang->mdio);
59 }
60
mdio_set(struct mdiobb_ctrl * ctrl,int what)61 static void mdio_set(struct mdiobb_ctrl *ctrl, int what)
62 {
63 struct mdio_gpio_info *bitbang =
64 container_of(ctrl, struct mdio_gpio_info, ctrl);
65
66 gpio_set_value(bitbang->mdio, what);
67 }
68
mdc_set(struct mdiobb_ctrl * ctrl,int what)69 static void mdc_set(struct mdiobb_ctrl *ctrl, int what)
70 {
71 struct mdio_gpio_info *bitbang =
72 container_of(ctrl, struct mdio_gpio_info, ctrl);
73
74 gpio_set_value(bitbang->mdc, what);
75 }
76
77 static struct mdiobb_ops mdio_gpio_ops = {
78 .owner = THIS_MODULE,
79 .set_mdc = mdc_set,
80 .set_mdio_dir = mdio_dir,
81 .set_mdio_data = mdio_set,
82 .get_mdio_data = mdio_get,
83 };
84
mdio_gpio_bus_init(struct device * dev,struct mdio_gpio_platform_data * pdata,int bus_id)85 static struct mii_bus * __devinit mdio_gpio_bus_init(struct device *dev,
86 struct mdio_gpio_platform_data *pdata,
87 int bus_id)
88 {
89 struct mii_bus *new_bus;
90 struct mdio_gpio_info *bitbang;
91 int i;
92
93 bitbang = kzalloc(sizeof(*bitbang), GFP_KERNEL);
94 if (!bitbang)
95 goto out;
96
97 bitbang->ctrl.ops = &mdio_gpio_ops;
98 bitbang->ctrl.reset = pdata->reset;
99 bitbang->mdc = pdata->mdc;
100 bitbang->mdio = pdata->mdio;
101
102 new_bus = alloc_mdio_bitbang(&bitbang->ctrl);
103 if (!new_bus)
104 goto out_free_bitbang;
105
106 new_bus->name = "GPIO Bitbanged MDIO",
107
108 new_bus->phy_mask = pdata->phy_mask;
109 new_bus->irq = pdata->irqs;
110 new_bus->parent = dev;
111
112 if (new_bus->phy_mask == ~0)
113 goto out_free_bus;
114
115 for (i = 0; i < PHY_MAX_ADDR; i++)
116 if (!new_bus->irq[i])
117 new_bus->irq[i] = PHY_POLL;
118
119 snprintf(new_bus->id, MII_BUS_ID_SIZE, "gpio-%x", bus_id);
120
121 if (gpio_request(bitbang->mdc, "mdc"))
122 goto out_free_bus;
123
124 if (gpio_request(bitbang->mdio, "mdio"))
125 goto out_free_mdc;
126
127 gpio_direction_output(bitbang->mdc, 0);
128
129 dev_set_drvdata(dev, new_bus);
130
131 return new_bus;
132
133 out_free_mdc:
134 gpio_free(bitbang->mdc);
135 out_free_bus:
136 free_mdio_bitbang(new_bus);
137 out_free_bitbang:
138 kfree(bitbang);
139 out:
140 return NULL;
141 }
142
mdio_gpio_bus_deinit(struct device * dev)143 static void mdio_gpio_bus_deinit(struct device *dev)
144 {
145 struct mii_bus *bus = dev_get_drvdata(dev);
146 struct mdio_gpio_info *bitbang = bus->priv;
147
148 dev_set_drvdata(dev, NULL);
149 gpio_free(bitbang->mdio);
150 gpio_free(bitbang->mdc);
151 free_mdio_bitbang(bus);
152 kfree(bitbang);
153 }
154
mdio_gpio_bus_destroy(struct device * dev)155 static void __devexit mdio_gpio_bus_destroy(struct device *dev)
156 {
157 struct mii_bus *bus = dev_get_drvdata(dev);
158
159 mdiobus_unregister(bus);
160 mdio_gpio_bus_deinit(dev);
161 }
162
mdio_gpio_probe(struct platform_device * pdev)163 static int __devinit mdio_gpio_probe(struct platform_device *pdev)
164 {
165 struct mdio_gpio_platform_data *pdata = pdev->dev.platform_data;
166 struct mii_bus *new_bus;
167 int ret;
168
169 if (!pdata)
170 return -ENODEV;
171
172 new_bus = mdio_gpio_bus_init(&pdev->dev, pdata, pdev->id);
173 if (!new_bus)
174 return -ENODEV;
175
176 ret = mdiobus_register(new_bus);
177 if (ret)
178 mdio_gpio_bus_deinit(&pdev->dev);
179
180 return ret;
181 }
182
mdio_gpio_remove(struct platform_device * pdev)183 static int __devexit mdio_gpio_remove(struct platform_device *pdev)
184 {
185 mdio_gpio_bus_destroy(&pdev->dev);
186
187 return 0;
188 }
189
190 #ifdef CONFIG_OF_GPIO
191
mdio_ofgpio_probe(struct platform_device * ofdev)192 static int __devinit mdio_ofgpio_probe(struct platform_device *ofdev)
193 {
194 struct mdio_gpio_platform_data *pdata;
195 struct mii_bus *new_bus;
196 int ret;
197
198 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
199 if (!pdata)
200 return -ENOMEM;
201
202 ret = of_get_gpio(ofdev->dev.of_node, 0);
203 if (ret < 0)
204 goto out_free;
205 pdata->mdc = ret;
206
207 ret = of_get_gpio(ofdev->dev.of_node, 1);
208 if (ret < 0)
209 goto out_free;
210 pdata->mdio = ret;
211
212 new_bus = mdio_gpio_bus_init(&ofdev->dev, pdata, pdata->mdc);
213 if (!new_bus)
214 goto out_free;
215
216 ret = of_mdiobus_register(new_bus, ofdev->dev.of_node);
217 if (ret)
218 mdio_gpio_bus_deinit(&ofdev->dev);
219
220 return ret;
221
222 out_free:
223 kfree(pdata);
224 return -ENODEV;
225 }
226
mdio_ofgpio_remove(struct platform_device * ofdev)227 static int __devexit mdio_ofgpio_remove(struct platform_device *ofdev)
228 {
229 mdio_gpio_bus_destroy(&ofdev->dev);
230 kfree(ofdev->dev.platform_data);
231
232 return 0;
233 }
234
235 static struct of_device_id mdio_ofgpio_match[] = {
236 {
237 .compatible = "virtual,mdio-gpio",
238 },
239 {},
240 };
241 MODULE_DEVICE_TABLE(of, mdio_ofgpio_match);
242
243 static struct platform_driver mdio_ofgpio_driver = {
244 .driver = {
245 .name = "mdio-ofgpio",
246 .owner = THIS_MODULE,
247 .of_match_table = mdio_ofgpio_match,
248 },
249 .probe = mdio_ofgpio_probe,
250 .remove = __devexit_p(mdio_ofgpio_remove),
251 };
252
mdio_ofgpio_init(void)253 static inline int __init mdio_ofgpio_init(void)
254 {
255 return platform_driver_register(&mdio_ofgpio_driver);
256 }
257
mdio_ofgpio_exit(void)258 static inline void __exit mdio_ofgpio_exit(void)
259 {
260 platform_driver_unregister(&mdio_ofgpio_driver);
261 }
262 #else
mdio_ofgpio_init(void)263 static inline int __init mdio_ofgpio_init(void) { return 0; }
mdio_ofgpio_exit(void)264 static inline void __exit mdio_ofgpio_exit(void) { }
265 #endif /* CONFIG_OF_GPIO */
266
267 static struct platform_driver mdio_gpio_driver = {
268 .probe = mdio_gpio_probe,
269 .remove = __devexit_p(mdio_gpio_remove),
270 .driver = {
271 .name = "mdio-gpio",
272 .owner = THIS_MODULE,
273 },
274 };
275
mdio_gpio_init(void)276 static int __init mdio_gpio_init(void)
277 {
278 int ret;
279
280 ret = mdio_ofgpio_init();
281 if (ret)
282 return ret;
283
284 ret = platform_driver_register(&mdio_gpio_driver);
285 if (ret)
286 mdio_ofgpio_exit();
287
288 return ret;
289 }
290 module_init(mdio_gpio_init);
291
mdio_gpio_exit(void)292 static void __exit mdio_gpio_exit(void)
293 {
294 platform_driver_unregister(&mdio_gpio_driver);
295 mdio_ofgpio_exit();
296 }
297 module_exit(mdio_gpio_exit);
298
299 MODULE_ALIAS("platform:mdio-gpio");
300 MODULE_AUTHOR("Laurent Pinchart, Paulius Zaleckas");
301 MODULE_LICENSE("GPL");
302 MODULE_DESCRIPTION("Generic driver for MDIO bus emulation using GPIO");
303