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_platform.h>
  34 #endif
  35
  36 struct mdio_gpio_info {
  37         struct mdiobb_ctrl ctrl;
  38         int mdc, mdio;
  39 };
  40
  41 static void mdio_dir(struct mdiobb_ctrl *ctrl, int dir)
  42 {
  43         struct mdio_gpio_info *bitbang =
  44                 container_of(ctrl, struct mdio_gpio_info, ctrl);
  45
  46         if (dir)
  47                 gpio_direction_output(bitbang->mdio, 1);
  48         else
  49                 gpio_direction_input(bitbang->mdio);
  50 }
  51
  52 static int mdio_get(struct mdiobb_ctrl *ctrl)
  53 {
  54         struct mdio_gpio_info *bitbang =
  55                 container_of(ctrl, struct mdio_gpio_info, ctrl);
  56
  57         return gpio_get_value(bitbang->mdio);
  58 }
  59
  60 static void mdio_set(struct mdiobb_ctrl *ctrl, int what)
  61 {
  62         struct mdio_gpio_info *bitbang =
  63                 container_of(ctrl, struct mdio_gpio_info, ctrl);
  64
  65         gpio_set_value(bitbang->mdio, what);
  66 }
  67
  68 static void mdc_set(struct mdiobb_ctrl *ctrl, int what)
  69 {
  70         struct mdio_gpio_info *bitbang =
  71                 container_of(ctrl, struct mdio_gpio_info, ctrl);
  72
  73         gpio_set_value(bitbang->mdc, what);
  74 }
  75
  76 static struct mdiobb_ops mdio_gpio_ops = {
  77         .owner = THIS_MODULE,
  78         .set_mdc = mdc_set,
  79         .set_mdio_dir = mdio_dir,
  80         .set_mdio_data = mdio_set,
  81         .get_mdio_data = mdio_get,
  82 };
  83
  84 static int __devinit mdio_gpio_bus_init(struct device *dev,
  85                                         struct mdio_gpio_platform_data *pdata,
  86                                         int bus_id)
  87 {
  88         struct mii_bus *new_bus;
  89         struct mdio_gpio_info *bitbang;
  90         int ret = -ENOMEM;
  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         ret = -ENODEV;
 108
 109         new_bus->phy_mask = pdata->phy_mask;
 110         new_bus->irq = pdata->irqs;
 111         new_bus->parent = dev;
 112
 113         if (new_bus->phy_mask == ~0)
 114                 goto out_free_bus;
 115
 116         for (i = 0; i < PHY_MAX_ADDR; i++)
 117                 if (!new_bus->irq[i])
 118                         new_bus->irq[i] = PHY_POLL;
 119
 120         snprintf(new_bus->id, MII_BUS_ID_SIZE, "%x", bus_id);
 121
 122         if (gpio_request(bitbang->mdc, "mdc"))
 123                 goto out_free_bus;
 124
 125         if (gpio_request(bitbang->mdio, "mdio"))
 126                 goto out_free_mdc;
 127
 128         gpio_direction_output(bitbang->mdc, 0);
 129
 130         dev_set_drvdata(dev, new_bus);
 131
 132         ret = mdiobus_register(new_bus);
 133         if (ret)
 134                 goto out_free_all;
 135
 136         return 0;
 137
 138 out_free_all:
 139         dev_set_drvdata(dev, NULL);
 140         gpio_free(bitbang->mdio);
 141 out_free_mdc:
 142         gpio_free(bitbang->mdc);
 143 out_free_bus:
 144         free_mdio_bitbang(new_bus);
 145 out_free_bitbang:
 146         kfree(bitbang);
 147 out:
 148         return ret;
 149 }
 150
 151 static void __devexit mdio_gpio_bus_destroy(struct device *dev)
 152 {
 153         struct mii_bus *bus = dev_get_drvdata(dev);
 154         struct mdio_gpio_info *bitbang = bus->priv;
 155
 156         mdiobus_unregister(bus);
 157         free_mdio_bitbang(bus);
 158         dev_set_drvdata(dev, NULL);
 159         gpio_free(bitbang->mdc);
 160         gpio_free(bitbang->mdio);
 161         kfree(bitbang);
 162 }
 163
 164 static int __devinit mdio_gpio_probe(struct platform_device *pdev)
 165 {
 166         struct mdio_gpio_platform_data *pdata = pdev->dev.platform_data;
 167
 168         if (!pdata)
 169                 return -ENODEV;
 170
 171         return mdio_gpio_bus_init(&pdev->dev, pdata, pdev->id);
 172 }
 173
 174 static int __devexit mdio_gpio_remove(struct platform_device *pdev)
 175 {
 176         mdio_gpio_bus_destroy(&pdev->dev);
 177
 178         return 0;
 179 }
 180
 181 #ifdef CONFIG_OF_GPIO
 182 static void __devinit add_phy(struct mdio_gpio_platform_data *pdata,
 183                               struct device_node *np)
 184 {
 185         const u32 *data;
 186         int len, id, irq;
 187
 188         data = of_get_property(np, "reg", &len);
 189         if (!data || len != 4)
 190                 return;
 191
 192         id = *data;
 193         pdata->phy_mask &= ~(1 << id);
 194
 195         irq = of_irq_to_resource(np, 0, NULL);
 196         if (irq)
 197                 pdata->irqs[id] = irq;
 198 }
 199
 200 static int __devinit mdio_ofgpio_probe(struct of_device *ofdev,
 201                                         const struct of_device_id *match)
 202 {
 203         struct device_node *np = NULL;
 204         struct mdio_gpio_platform_data *pdata;
 205         int ret;
 206
 207         pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
 208         if (!pdata)
 209                 return -ENOMEM;
 210
 211         ret = of_get_gpio(ofdev->node, 0);
 212         if (ret < 0)
 213                 goto out_free;
 214         pdata->mdc = ret;
 215
 216         ret = of_get_gpio(ofdev->node, 1);
 217         if (ret < 0)
 218                 goto out_free;
 219         pdata->mdio = ret;
 220
 221         while ((np = of_get_next_child(ofdev->node, np)))
 222                 if (!strcmp(np->type, "ethernet-phy"))
 223                         add_phy(pdata, np);
 224
 225         return mdio_gpio_bus_init(&ofdev->dev, pdata, pdata->mdc);
 226
 227 out_free:
 228         kfree(pdata);
 229         return -ENODEV;
 230 }
 231
 232 static int __devexit mdio_ofgpio_remove(struct of_device *ofdev)
 233 {
 234         mdio_gpio_bus_destroy(&ofdev->dev);
 235         kfree(ofdev->dev.platform_data);
 236
 237         return 0;
 238 }
 239
 240 static struct of_device_id mdio_ofgpio_match[] = {
 241         {
 242                 .compatible = "virtual,mdio-gpio",
 243         },
 244         {},
 245 };
 246
 247 static struct of_platform_driver mdio_ofgpio_driver = {
 248         .name = "mdio-gpio",
 249         .match_table = mdio_ofgpio_match,
 250         .probe = mdio_ofgpio_probe,
 251         .remove = __devexit_p(mdio_ofgpio_remove),
 252 };
 253
 254 static inline int __init mdio_ofgpio_init(void)
 255 {
 256         return of_register_platform_driver(&mdio_ofgpio_driver);
 257 }
 258
 259 static inline void __exit mdio_ofgpio_exit(void)
 260 {
 261         of_unregister_platform_driver(&mdio_ofgpio_driver);
 262 }
 263 #else
 264 static inline int __init mdio_ofgpio_init(void) { return 0; }
 265 static inline void __exit mdio_ofgpio_exit(void) { }
 266 #endif /* CONFIG_OF_GPIO */
 267
 268 static struct platform_driver mdio_gpio_driver = {
 269         .probe = mdio_gpio_probe,
 270         .remove = __devexit_p(mdio_gpio_remove),
 271         .driver         = {
 272                 .name   = "mdio-gpio",
 273                 .owner  = THIS_MODULE,
 274         },
 275 };
 276
 277 static int __init mdio_gpio_init(void)
 278 {
 279         int ret;
 280
 281         ret = mdio_ofgpio_init();
 282         if (ret)
 283                 return ret;
 284
 285         ret = platform_driver_register(&mdio_gpio_driver);
 286         if (ret)
 287                 mdio_ofgpio_exit();
 288
 289         return ret;
 290 }
 291 module_init(mdio_gpio_init);
 292
 293 static void __exit mdio_gpio_exit(void)
 294 {
 295         platform_driver_unregister(&mdio_gpio_driver);
 296         mdio_ofgpio_exit();
 297 }
 298 module_exit(mdio_gpio_exit);
 299
 300 MODULE_ALIAS("platform:mdio-gpio");
 301 MODULE_AUTHOR("Laurent Pinchart, Paulius Zaleckas");
 302 MODULE_LICENSE("GPL");
 303 MODULE_DESCRIPTION("Generic driver for MDIO bus emulation using GPIO");