drivers/net/fs_enet/mii-bitbang.c

   1 /*
   2  * Combined Ethernet driver for Motorola MPC8xx and MPC82xx.
   3  *
   4  * Copyright (c) 2003 Intracom S.A.
   5  *  by Pantelis Antoniou <panto@intracom.gr>
   6  *
   7  * 2005 (c) MontaVista Software, Inc.
   8  * Vitaly Bordug <vbordug@ru.mvista.com>
   9  *
  10  * This file is licensed under the terms of the GNU General Public License
  11  * version 2. This program is licensed "as is" without any warranty of any
  12  * kind, whether express or implied.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/ioport.h>
  17 #include <linux/slab.h>
  18 #include <linux/init.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/netdevice.h>
  21 #include <linux/etherdevice.h>
  22 #include <linux/mii.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/mdio-bitbang.h>
  25 #include <linux/of_platform.h>
  26
  27 #include "fs_enet.h"
  28
  29 struct bb_info {
  30         struct mdiobb_ctrl ctrl;
  31         __be32 __iomem *dir;
  32         __be32 __iomem *dat;
  33         u32 mdio_msk;
  34         u32 mdc_msk;
  35 };
  36
  37 /* FIXME: If any other users of GPIO crop up, then these will have to
  38  * have some sort of global synchronization to avoid races with other
  39  * pins on the same port.  The ideal solution would probably be to
  40  * bind the ports to a GPIO driver, and have this be a client of it.
  41  */
  42 static inline void bb_set(u32 __iomem *p, u32 m)
  43 {
  44         out_be32(p, in_be32(p) | m);
  45 }
  46
  47 static inline void bb_clr(u32 __iomem *p, u32 m)
  48 {
  49         out_be32(p, in_be32(p) & ~m);
  50 }
  51
  52 static inline int bb_read(u32 __iomem *p, u32 m)
  53 {
  54         return (in_be32(p) & m) != 0;
  55 }
  56
  57 static inline void mdio_dir(struct mdiobb_ctrl *ctrl, int dir)
  58 {
  59         struct bb_info *bitbang = container_of(ctrl, struct bb_info, ctrl);
  60
  61         if (dir)
  62                 bb_set(bitbang->dir, bitbang->mdio_msk);
  63         else
  64                 bb_clr(bitbang->dir, bitbang->mdio_msk);
  65
  66         /* Read back to flush the write. */
  67         in_be32(bitbang->dir);
  68 }
  69
  70 static inline int mdio_read(struct mdiobb_ctrl *ctrl)
  71 {
  72         struct bb_info *bitbang = container_of(ctrl, struct bb_info, ctrl);
  73         return bb_read(bitbang->dat, bitbang->mdio_msk);
  74 }
  75
  76 static inline void mdio(struct mdiobb_ctrl *ctrl, int what)
  77 {
  78         struct bb_info *bitbang = container_of(ctrl, struct bb_info, ctrl);
  79
  80         if (what)
  81                 bb_set(bitbang->dat, bitbang->mdio_msk);
  82         else
  83                 bb_clr(bitbang->dat, bitbang->mdio_msk);
  84
  85         /* Read back to flush the write. */
  86         in_be32(bitbang->dat);
  87 }
  88
  89 static inline void mdc(struct mdiobb_ctrl *ctrl, int what)
  90 {
  91         struct bb_info *bitbang = container_of(ctrl, struct bb_info, ctrl);
  92
  93         if (what)
  94                 bb_set(bitbang->dat, bitbang->mdc_msk);
  95         else
  96                 bb_clr(bitbang->dat, bitbang->mdc_msk);
  97
  98         /* Read back to flush the write. */
  99         in_be32(bitbang->dat);
 100 }
 101
 102 static struct mdiobb_ops bb_ops = {
 103         .owner = THIS_MODULE,
 104         .set_mdc = mdc,
 105         .set_mdio_dir = mdio_dir,
 106         .set_mdio_data = mdio,
 107         .get_mdio_data = mdio_read,
 108 };
 109
 110 static int __devinit fs_mii_bitbang_init(struct mii_bus *bus,
 111                                          struct device_node *np)
 112 {
 113         struct resource res;
 114         const u32 *data;
 115         int mdio_pin, mdc_pin, len;
 116         struct bb_info *bitbang = bus->priv;
 117
 118         int ret = of_address_to_resource(np, 0, &res);
 119         if (ret)
 120                 return ret;
 121
 122         if (res.end - res.start < 13)
 123                 return -ENODEV;
 124
 125         /* This should really encode the pin number as well, but all
 126          * we get is an int, and the odds of multiple bitbang mdio buses
 127          * is low enough that it's not worth going too crazy.
 128          */
 129         snprintf(bus->id, MII_BUS_ID_SIZE, "%x", res.start);
 130
 131         data = of_get_property(np, "fsl,mdio-pin", &len);
 132         if (!data || len != 4)
 133                 return -ENODEV;
 134         mdio_pin = *data;
 135
 136         data = of_get_property(np, "fsl,mdc-pin", &len);
 137         if (!data || len != 4)
 138                 return -ENODEV;
 139         mdc_pin = *data;
 140
 141         bitbang->dir = ioremap(res.start, res.end - res.start + 1);
 142         if (!bitbang->dir)
 143                 return -ENOMEM;
 144
 145         bitbang->dat = bitbang->dir + 4;
 146         bitbang->mdio_msk = 1 << (31 - mdio_pin);
 147         bitbang->mdc_msk = 1 << (31 - mdc_pin);
 148
 149         return 0;
 150 }
 151
 152 static void __devinit add_phy(struct mii_bus *bus, struct device_node *np)
 153 {
 154         const u32 *data;
 155         int len, id, irq;
 156
 157         data = of_get_property(np, "reg", &len);
 158         if (!data || len != 4)
 159                 return;
 160
 161         id = *data;
 162         bus->phy_mask &= ~(1 << id);
 163
 164         irq = of_irq_to_resource(np, 0, NULL);
 165         if (irq != NO_IRQ)
 166                 bus->irq[id] = irq;
 167 }
 168
 169 static int __devinit fs_enet_mdio_probe(struct of_device *ofdev,
 170                                         const struct of_device_id *match)
 171 {
 172         struct device_node *np = NULL;
 173         struct mii_bus *new_bus;
 174         struct bb_info *bitbang;
 175         int ret = -ENOMEM;
 176         int i;
 177
 178         bitbang = kzalloc(sizeof(struct bb_info), GFP_KERNEL);
 179         if (!bitbang)
 180                 goto out;
 181
 182         bitbang->ctrl.ops = &bb_ops;
 183
 184         new_bus = alloc_mdio_bitbang(&bitbang->ctrl);
 185         if (!new_bus)
 186                 goto out_free_priv;
 187
 188         new_bus->name = "CPM2 Bitbanged MII",
 189
 190         ret = fs_mii_bitbang_init(new_bus, ofdev->node);
 191         if (ret)
 192                 goto out_free_bus;
 193
 194         new_bus->phy_mask = ~0;
 195         new_bus->irq = kmalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
 196         if (!new_bus->irq)
 197                 goto out_unmap_regs;
 198
 199         for (i = 0; i < PHY_MAX_ADDR; i++)
 200                 new_bus->irq[i] = -1;
 201
 202         while ((np = of_get_next_child(ofdev->node, np)))
 203                 if (!strcmp(np->type, "ethernet-phy"))
 204                         add_phy(new_bus, np);
 205
 206         new_bus->dev = &ofdev->dev;
 207         dev_set_drvdata(&ofdev->dev, new_bus);
 208
 209         ret = mdiobus_register(new_bus);
 210         if (ret)
 211                 goto out_free_irqs;
 212
 213         return 0;
 214
 215 out_free_irqs:
 216         dev_set_drvdata(&ofdev->dev, NULL);
 217         kfree(new_bus->irq);
 218 out_unmap_regs:
 219         iounmap(bitbang->dir);
 220 out_free_bus:
 221         kfree(new_bus);
 222 out_free_priv:
 223         free_mdio_bitbang(new_bus);
 224 out:
 225         return ret;
 226 }
 227
 228 static int fs_enet_mdio_remove(struct of_device *ofdev)
 229 {
 230         struct mii_bus *bus = dev_get_drvdata(&ofdev->dev);
 231         struct bb_info *bitbang = bus->priv;
 232
 233         mdiobus_unregister(bus);
 234         free_mdio_bitbang(bus);
 235         dev_set_drvdata(&ofdev->dev, NULL);
 236         kfree(bus->irq);
 237         iounmap(bitbang->dir);
 238         kfree(bitbang);
 239         kfree(bus);
 240
 241         return 0;
 242 }
 243
 244 static struct of_device_id fs_enet_mdio_bb_match[] = {
 245         {
 246                 .compatible = "fsl,cpm2-mdio-bitbang",
 247         },
 248         {},
 249 };
 250
 251 static struct of_platform_driver fs_enet_bb_mdio_driver = {
 252         .name = "fsl-bb-mdio",
 253         .match_table = fs_enet_mdio_bb_match,
 254         .probe = fs_enet_mdio_probe,
 255         .remove = fs_enet_mdio_remove,
 256 };
 257
 258 static int fs_enet_mdio_bb_init(void)
 259 {
 260         return of_register_platform_driver(&fs_enet_bb_mdio_driver);
 261 }
 262
 263 static void fs_enet_mdio_bb_exit(void)
 264 {
 265         of_unregister_platform_driver(&fs_enet_bb_mdio_driver);
 266 }
 267
 268 module_init(fs_enet_mdio_bb_init);
 269 module_exit(fs_enet_mdio_bb_exit);