drivers/net/phy/mdio-gpio.c

   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
  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
  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
  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
  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
  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->mdc = pdata->mdc;
  99         bitbang->mdio = pdata->mdio;
 100
 101         new_bus = alloc_mdio_bitbang(&bitbang->ctrl);
 102         if (!new_bus)
 103                 goto out_free_bitbang;
 104
 105         new_bus->name = "GPIO Bitbanged MDIO",
 106
 107         new_bus->phy_mask = pdata->phy_mask;
 108         new_bus->irq = pdata->irqs;
 109         new_bus->parent = dev;
 110
 111         if (new_bus->phy_mask == ~0)
 112                 goto out_free_bus;
 113
 114         for (i = 0; i < PHY_MAX_ADDR; i++)
 115                 if (!new_bus->irq[i])
 116                         new_bus->irq[i] = PHY_POLL;
 117
 118         snprintf(new_bus->id, MII_BUS_ID_SIZE, "%x", bus_id);
 119
 120         if (gpio_request(bitbang->mdc, "mdc"))
 121                 goto out_free_bus;
 122
 123         if (gpio_request(bitbang->mdio, "mdio"))
 124                 goto out_free_mdc;
 125
 126         gpio_direction_output(bitbang->mdc, 0);
 127
 128         dev_set_drvdata(dev, new_bus);
 129
 130         return new_bus;
 131
 132 out_free_mdc:
 133         gpio_free(bitbang->mdc);
 134 out_free_bus:
 135         free_mdio_bitbang(new_bus);
 136 out_free_bitbang:
 137         kfree(bitbang);
 138 out:
 139         return NULL;
 140 }
 141
 142 static void mdio_gpio_bus_deinit(struct device *dev)
 143 {
 144         struct mii_bus *bus = dev_get_drvdata(dev);
 145         struct mdio_gpio_info *bitbang = bus->priv;
 146
 147         dev_set_drvdata(dev, NULL);
 148         gpio_free(bitbang->mdio);
 149         gpio_free(bitbang->mdc);
 150         free_mdio_bitbang(bus);
 151         kfree(bitbang);
 152 }
 153
 154 static void __devexit mdio_gpio_bus_destroy(struct device *dev)
 155 {
 156         struct mii_bus *bus = dev_get_drvdata(dev);
 157
 158         mdiobus_unregister(bus);
 159         mdio_gpio_bus_deinit(dev);
 160 }
 161
 162 static int __devinit mdio_gpio_probe(struct platform_device *pdev)
 163 {
 164         struct mdio_gpio_platform_data *pdata = pdev->dev.platform_data;
 165         struct mii_bus *new_bus;
 166         int ret;
 167
 168         if (!pdata)
 169                 return -ENODEV;
 170
 171         new_bus = mdio_gpio_bus_init(&pdev->dev, pdata, pdev->id);
 172         if (!new_bus)
 173                 return -ENODEV;
 174
 175         ret = mdiobus_register(new_bus);
 176         if (ret)
 177                 mdio_gpio_bus_deinit(&pdev->dev);
 178
 179         return ret;
 180 }
 181
 182 static int __devexit mdio_gpio_remove(struct platform_device *pdev)
 183 {
 184         mdio_gpio_bus_destroy(&pdev->dev);
 185
 186         return 0;
 187 }
 188
 189 #ifdef CONFIG_OF_GPIO
 190
 191 static int __devinit mdio_ofgpio_probe(struct platform_device *ofdev,
 192                                         const struct of_device_id *match)
 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
 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 of_platform_driver mdio_ofgpio_driver = {
 244         .driver = {
 245                 .name = "mdio-gpio",
 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
 253 static inline int __init mdio_ofgpio_init(void)
 254 {
 255         return of_register_platform_driver(&mdio_ofgpio_driver);
 256 }
 257
 258 static inline void __exit mdio_ofgpio_exit(void)
 259 {
 260         of_unregister_platform_driver(&mdio_ofgpio_driver);
 261 }
 262 #else
 263 static inline int __init mdio_ofgpio_init(void) { return 0; }
 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
 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
 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");