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         dev_set_drvdata(dev, new_bus);
 129
 130         ret = mdiobus_register(new_bus);
 131         if (ret)
 132                 goto out_free_all;
 133
 134         return 0;
 135
 136 out_free_all:
 137         dev_set_drvdata(dev, NULL);
 138         gpio_free(bitbang->mdio);
 139 out_free_mdc:
 140         gpio_free(bitbang->mdc);
 141 out_free_bus:
 142         free_mdio_bitbang(new_bus);
 143 out_free_bitbang:
 144         kfree(bitbang);
 145 out:
 146         return ret;
 147 }
 148
 149 static void __devexit mdio_gpio_bus_destroy(struct device *dev)
 150 {
 151         struct mii_bus *bus = dev_get_drvdata(dev);
 152         struct mdio_gpio_info *bitbang = bus->priv;
 153
 154         mdiobus_unregister(bus);
 155         free_mdio_bitbang(bus);
 156         dev_set_drvdata(dev, NULL);
 157         gpio_free(bitbang->mdc);
 158         gpio_free(bitbang->mdio);
 159         kfree(bitbang);
 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
 166         if (!pdata)
 167                 return -ENODEV;
 168
 169         return mdio_gpio_bus_init(&pdev->dev, pdata, pdev->id);
 170 }
 171
 172 static int __devexit mdio_gpio_remove(struct platform_device *pdev)
 173 {
 174         mdio_gpio_bus_destroy(&pdev->dev);
 175
 176         return 0;
 177 }
 178
 179 #ifdef CONFIG_OF_GPIO
 180 static void __devinit add_phy(struct mdio_gpio_platform_data *pdata,
 181                               struct device_node *np)
 182 {
 183         const u32 *data;
 184         int len, id, irq;
 185
 186         data = of_get_property(np, "reg", &len);
 187         if (!data || len != 4)
 188                 return;
 189
 190         id = *data;
 191         pdata->phy_mask &= ~(1 << id);
 192
 193         irq = of_irq_to_resource(np, 0, NULL);
 194         if (irq)
 195                 pdata->irqs[id] = irq;
 196 }
 197
 198 static int __devinit mdio_ofgpio_probe(struct of_device *ofdev,
 199                                         const struct of_device_id *match)
 200 {
 201         struct device_node *np = NULL;
 202         struct mdio_gpio_platform_data *pdata;
 203
 204         pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
 205         if (!pdata)
 206                 return -ENOMEM;
 207
 208         pdata->mdc = of_get_gpio(ofdev->node, 0);
 209         pdata->mdio = of_get_gpio(ofdev->node, 1);
 210
 211         if (pdata->mdc < 0 || pdata->mdio < 0)
 212                 goto out_free;
 213
 214         while ((np = of_get_next_child(ofdev->node, np)))
 215                 if (!strcmp(np->type, "ethernet-phy"))
 216                         add_phy(pdata, np);
 217
 218         return mdio_gpio_bus_init(&ofdev->dev, pdata, pdata->mdc);
 219
 220 out_free:
 221         kfree(pdata);
 222         return -ENODEV;
 223 }
 224
 225 static int __devexit mdio_ofgpio_remove(struct of_device *ofdev)
 226 {
 227         mdio_gpio_bus_destroy(&ofdev->dev);
 228         kfree(ofdev->dev.platform_data);
 229
 230         return 0;
 231 }
 232
 233 static struct of_device_id mdio_ofgpio_match[] = {
 234         {
 235                 .compatible = "virtual,mdio-gpio",
 236         },
 237         {},
 238 };
 239
 240 static struct of_platform_driver mdio_ofgpio_driver = {
 241         .name = "mdio-gpio",
 242         .match_table = mdio_ofgpio_match,
 243         .probe = mdio_ofgpio_probe,
 244         .remove = __devexit_p(mdio_ofgpio_remove),
 245 };
 246
 247 static inline int __init mdio_ofgpio_init(void)
 248 {
 249         return of_register_platform_driver(&mdio_ofgpio_driver);
 250 }
 251
 252 static inline void __exit mdio_ofgpio_exit(void)
 253 {
 254         of_unregister_platform_driver(&mdio_ofgpio_driver);
 255 }
 256 #else
 257 static inline int __init mdio_ofgpio_init(void) { return 0; }
 258 static inline void __exit mdio_ofgpio_exit(void) { }
 259 #endif /* CONFIG_OF_GPIO */
 260
 261 static struct platform_driver mdio_gpio_driver = {
 262         .probe = mdio_gpio_probe,
 263         .remove = __devexit_p(mdio_gpio_remove),
 264         .driver         = {
 265                 .name   = "mdio-gpio",
 266                 .owner  = THIS_MODULE,
 267         },
 268 };
 269
 270 static int __init mdio_gpio_init(void)
 271 {
 272         int ret;
 273
 274         ret = mdio_ofgpio_init();
 275         if (ret)
 276                 return ret;
 277
 278         ret = platform_driver_register(&mdio_gpio_driver);
 279         if (ret)
 280                 mdio_ofgpio_exit();
 281
 282         return ret;
 283 }
 284 module_init(mdio_gpio_init);
 285
 286 static void __exit mdio_gpio_exit(void)
 287 {
 288         platform_driver_unregister(&mdio_gpio_driver);
 289         mdio_ofgpio_exit();
 290 }
 291 module_exit(mdio_gpio_exit);
 292
 293 MODULE_ALIAS("platform:mdio-gpio");
 294 MODULE_AUTHOR("Laurent Pinchart, Paulius Zaleckas");
 295 MODULE_LICENSE("GPL");
 296 MODULE_DESCRIPTION("Generic driver for MDIO bus emulation using GPIO");