drivers/net/phy/mdio-ofgpio.c

   1 /*
   2  * OpenFirmware GPIO based MDIO bitbang driver.
   3  *
   4  * Copyright (c) 2008 CSE Semaphore Belgium.
   5  *  by Laurent Pinchart <laurentp@cse-semaphore.com>
   6  *
   7  * Based on earlier work by
   8  *
   9  * Copyright (c) 2003 Intracom S.A.
  10  *  by Pantelis Antoniou <panto@intracom.gr>
  11  *
  12  * 2005 (c) MontaVista Software, Inc.
  13  * Vitaly Bordug <vbordug@ru.mvista.com>
  14  *
  15  * This file is licensed under the terms of the GNU General Public License
  16  * version 2. This program is licensed "as is" without any warranty of any
  17  * kind, whether express or implied.
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/slab.h>
  22 #include <linux/init.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/mdio-bitbang.h>
  25 #include <linux/of_gpio.h>
  26 #include <linux/of_platform.h>
  27
  28 struct mdio_gpio_info {
  29         struct mdiobb_ctrl ctrl;
  30         int mdc, mdio;
  31 };
  32
  33 static void mdio_dir(struct mdiobb_ctrl *ctrl, int dir)
  34 {
  35         struct mdio_gpio_info *bitbang =
  36                 container_of(ctrl, struct mdio_gpio_info, ctrl);
  37
  38         if (dir)
  39                 gpio_direction_output(bitbang->mdio, 1);
  40         else
  41                 gpio_direction_input(bitbang->mdio);
  42 }
  43
  44 static int mdio_read(struct mdiobb_ctrl *ctrl)
  45 {
  46         struct mdio_gpio_info *bitbang =
  47                 container_of(ctrl, struct mdio_gpio_info, ctrl);
  48
  49         return gpio_get_value(bitbang->mdio);
  50 }
  51
  52 static void mdio(struct mdiobb_ctrl *ctrl, int what)
  53 {
  54         struct mdio_gpio_info *bitbang =
  55                 container_of(ctrl, struct mdio_gpio_info, ctrl);
  56
  57         gpio_set_value(bitbang->mdio, what);
  58 }
  59
  60 static void mdc(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->mdc, what);
  66 }
  67
  68 static struct mdiobb_ops mdio_gpio_ops = {
  69         .owner = THIS_MODULE,
  70         .set_mdc = mdc,
  71         .set_mdio_dir = mdio_dir,
  72         .set_mdio_data = mdio,
  73         .get_mdio_data = mdio_read,
  74 };
  75
  76 static int __devinit mdio_ofgpio_bitbang_init(struct mii_bus *bus,
  77                                          struct device_node *np)
  78 {
  79         struct mdio_gpio_info *bitbang = bus->priv;
  80
  81         bitbang->mdc = of_get_gpio(np, 0);
  82         bitbang->mdio = of_get_gpio(np, 1);
  83
  84         if (bitbang->mdc < 0 || bitbang->mdio < 0)
  85                 return -ENODEV;
  86
  87         snprintf(bus->id, MII_BUS_ID_SIZE, "%x", bitbang->mdc);
  88         return 0;
  89 }
  90
  91 static void __devinit add_phy(struct mii_bus *bus, struct device_node *np)
  92 {
  93         const u32 *data;
  94         int len, id, irq;
  95
  96         data = of_get_property(np, "reg", &len);
  97         if (!data || len != 4)
  98                 return;
  99
 100         id = *data;
 101         bus->phy_mask &= ~(1 << id);
 102
 103         irq = of_irq_to_resource(np, 0, NULL);
 104         if (irq != NO_IRQ)
 105                 bus->irq[id] = irq;
 106 }
 107
 108 static int __devinit mdio_ofgpio_probe(struct of_device *ofdev,
 109                                         const struct of_device_id *match)
 110 {
 111         struct device_node *np = NULL;
 112         struct mii_bus *new_bus;
 113         struct mdio_gpio_info *bitbang;
 114         int ret = -ENOMEM;
 115         int i;
 116
 117         bitbang = kzalloc(sizeof(struct mdio_gpio_info), GFP_KERNEL);
 118         if (!bitbang)
 119                 goto out;
 120
 121         bitbang->ctrl.ops = &mdio_gpio_ops;
 122
 123         new_bus = alloc_mdio_bitbang(&bitbang->ctrl);
 124         if (!new_bus)
 125                 goto out_free_priv;
 126
 127         new_bus->name = "GPIO Bitbanged MII",
 128
 129         ret = mdio_ofgpio_bitbang_init(new_bus, ofdev->node);
 130         if (ret)
 131                 goto out_free_bus;
 132
 133         new_bus->phy_mask = ~0;
 134         new_bus->irq = kmalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
 135         if (!new_bus->irq)
 136                 goto out_free_bus;
 137
 138         for (i = 0; i < PHY_MAX_ADDR; i++)
 139                 new_bus->irq[i] = -1;
 140
 141         while ((np = of_get_next_child(ofdev->node, np)))
 142                 if (!strcmp(np->type, "ethernet-phy"))
 143                         add_phy(new_bus, np);
 144
 145         new_bus->dev = &ofdev->dev;
 146         dev_set_drvdata(&ofdev->dev, new_bus);
 147
 148         ret = mdiobus_register(new_bus);
 149         if (ret)
 150                 goto out_free_irqs;
 151
 152         return 0;
 153
 154 out_free_irqs:
 155         dev_set_drvdata(&ofdev->dev, NULL);
 156         kfree(new_bus->irq);
 157 out_free_bus:
 158         kfree(new_bus);
 159 out_free_priv:
 160         free_mdio_bitbang(new_bus);
 161 out:
 162         return ret;
 163 }
 164
 165 static int mdio_ofgpio_remove(struct of_device *ofdev)
 166 {
 167         struct mii_bus *bus = dev_get_drvdata(&ofdev->dev);
 168         struct mdio_gpio_info *bitbang = bus->priv;
 169
 170         mdiobus_unregister(bus);
 171         free_mdio_bitbang(bus);
 172         dev_set_drvdata(&ofdev->dev, NULL);
 173         kfree(bus->irq);
 174         kfree(bitbang);
 175         kfree(bus);
 176
 177         return 0;
 178 }
 179
 180 static struct of_device_id mdio_ofgpio_match[] = {
 181         {
 182                 .compatible = "virtual,mdio-gpio",
 183         },
 184         {},
 185 };
 186
 187 static struct of_platform_driver mdio_ofgpio_driver = {
 188         .name = "mdio-gpio",
 189         .match_table = mdio_ofgpio_match,
 190         .probe = mdio_ofgpio_probe,
 191         .remove = mdio_ofgpio_remove,
 192 };
 193
 194 static int mdio_ofgpio_init(void)
 195 {
 196         return of_register_platform_driver(&mdio_ofgpio_driver);
 197 }
 198
 199 static void mdio_ofgpio_exit(void)
 200 {
 201         of_unregister_platform_driver(&mdio_ofgpio_driver);
 202 }
 203
 204 module_init(mdio_ofgpio_init);
 205 module_exit(mdio_ofgpio_exit);