drivers/net/phy/fixed.c

   1 /*
   2  * drivers/net/phy/fixed.c
   3  *
   4  * Driver for fixed PHYs, when transceiver is able to operate in one fixed mode.
   5  *
   6  * Author: Vitaly Bordug
   7  *
   8  * Copyright (c) 2006 MontaVista Software, Inc.
   9  *
  10  * This program is free software; you can redistribute  it and/or modify it
  11  * under  the terms of  the GNU General  Public License as published by the
  12  * Free Software Foundation;  either version 2 of the  License, or (at your
  13  * option) any later version.
  14  *
  15  */
  16 #include <linux/kernel.h>
  17 #include <linux/string.h>
  18 #include <linux/errno.h>
  19 #include <linux/unistd.h>
  20 #include <linux/slab.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/init.h>
  23 #include <linux/delay.h>
  24 #include <linux/netdevice.h>
  25 #include <linux/etherdevice.h>
  26 #include <linux/skbuff.h>
  27 #include <linux/spinlock.h>
  28 #include <linux/mm.h>
  29 #include <linux/module.h>
  30 #include <linux/mii.h>
  31 #include <linux/ethtool.h>
  32 #include <linux/phy.h>
  33
  34 #include <asm/io.h>
  35 #include <asm/irq.h>
  36 #include <asm/uaccess.h>
  37
  38 #define MII_REGS_NUM    7
  39
  40 /*
  41     The idea is to emulate normal phy behavior by responding with
  42     pre-defined values to mii BMCR read, so that read_status hook could
  43     take all the needed info.
  44 */
  45
  46 struct fixed_phy_status {
  47         u8      link;
  48         u16     speed;
  49         u8      duplex;
  50 };
  51
  52 /*-----------------------------------------------------------------------------
  53  *  Private information hoder for mii_bus
  54  *-----------------------------------------------------------------------------*/
  55 struct fixed_info {
  56         u16 *regs;
  57         u8 regs_num;
  58         struct fixed_phy_status phy_status;
  59         struct phy_device *phydev; /* pointer to the container */
  60         /* link & speed cb */
  61         int(*link_update)(struct net_device*, struct fixed_phy_status*);
  62
  63 };
  64
  65 /*-----------------------------------------------------------------------------
  66  *  If something weird is required to be done with link/speed,
  67  * network driver is able to assign a function to implement this.
  68  * May be useful for PHY's that need to be software-driven.
  69  *-----------------------------------------------------------------------------*/
  70 int fixed_mdio_set_link_update(struct phy_device* phydev,
  71                 int(*link_update)(struct net_device*, struct fixed_phy_status*))
  72 {
  73         struct fixed_info *fixed;
  74
  75         if(link_update == NULL)
  76                 return -EINVAL;
  77
  78         if(phydev) {
  79                 if(phydev->bus) {
  80                         fixed = phydev->bus->priv;
  81                         fixed->link_update = link_update;
  82                         return 0;
  83                 }
  84         }
  85         return -EINVAL;
  86 }
  87 EXPORT_SYMBOL(fixed_mdio_set_link_update);
  88
  89 /*-----------------------------------------------------------------------------
  90  *  This is used for updating internal mii regs from the status
  91  *-----------------------------------------------------------------------------*/
  92 static int fixed_mdio_update_regs(struct fixed_info *fixed)
  93 {
  94         u16 *regs = fixed->regs;
  95         u16 bmsr = 0;
  96         u16 bmcr = 0;
  97
  98         if(!regs) {
  99                 printk(KERN_ERR "%s: regs not set up", __FUNCTION__);
 100                 return -EINVAL;
 101         }
 102
 103         if(fixed->phy_status.link)
 104                 bmsr |= BMSR_LSTATUS;
 105
 106         if(fixed->phy_status.duplex) {
 107                 bmcr |= BMCR_FULLDPLX;
 108
 109                 switch ( fixed->phy_status.speed ) {
 110                 case 100:
 111                         bmsr |= BMSR_100FULL;
 112                         bmcr |= BMCR_SPEED100;
 113                 break;
 114
 115                 case 10:
 116                         bmsr |= BMSR_10FULL;
 117                 break;
 118                 }
 119         } else {
 120                 switch ( fixed->phy_status.speed ) {
 121                 case 100:
 122                         bmsr |= BMSR_100HALF;
 123                         bmcr |= BMCR_SPEED100;
 124                 break;
 125
 126                 case 10:
 127                         bmsr |= BMSR_100HALF;
 128                 break;
 129                 }
 130         }
 131
 132         regs[MII_BMCR] =  bmcr;
 133         regs[MII_BMSR] =  bmsr | 0x800; /*we are always capable of 10 hdx*/
 134
 135         return 0;
 136 }
 137
 138 static int fixed_mii_read(struct mii_bus *bus, int phy_id, int location)
 139 {
 140         struct fixed_info *fixed = bus->priv;
 141
 142         /* if user has registered link update callback, use it */
 143         if(fixed->phydev)
 144                 if(fixed->phydev->attached_dev) {
 145                         if(fixed->link_update) {
 146                                 fixed->link_update(fixed->phydev->attached_dev,
 147                                                 &fixed->phy_status);
 148                                 fixed_mdio_update_regs(fixed);
 149                         }
 150         }
 151
 152         if ((unsigned int)location >= fixed->regs_num)
 153                 return -1;
 154         return fixed->regs[location];
 155 }
 156
 157 static int fixed_mii_write(struct mii_bus *bus, int phy_id, int location, u16 val)
 158 {
 159         /* do nothing for now*/
 160         return 0;
 161 }
 162
 163 static int fixed_mii_reset(struct mii_bus *bus)
 164 {
 165         /*nothing here - no way/need to reset it*/
 166         return 0;
 167 }
 168
 169 static int fixed_config_aneg(struct phy_device *phydev)
 170 {
 171         /* :TODO:03/13/2006 09:45:37 PM::
 172          The full autoneg funcionality can be emulated,
 173          but no need to have anything here for now
 174          */
 175         return 0;
 176 }
 177
 178 /*-----------------------------------------------------------------------------
 179  * the manual bind will do the magic - with phy_id_mask == 0
 180  * match will never return true...
 181  *-----------------------------------------------------------------------------*/
 182 static struct phy_driver fixed_mdio_driver = {
 183         .name           = "Fixed PHY",
 184         .features       = PHY_BASIC_FEATURES,
 185         .config_aneg    = fixed_config_aneg,
 186         .read_status    = genphy_read_status,
 187         .driver         = { .owner = THIS_MODULE,},
 188 };
 189
 190 /*-----------------------------------------------------------------------------
 191  *  This func is used to create all the necessary stuff, bind
 192  * the fixed phy driver and register all it on the mdio_bus_type.
 193  * speed is either 10 or 100, duplex is boolean.
 194  * number is used to create multiple fixed PHYs, so that several devices can
 195  * utilize them simultaneously.
 196  *-----------------------------------------------------------------------------*/
 197 static int fixed_mdio_register_device(int number, int speed, int duplex)
 198 {
 199         struct mii_bus *new_bus;
 200         struct fixed_info *fixed;
 201         struct phy_device *phydev;
 202         int err = 0;
 203
 204         struct device* dev = kzalloc(sizeof(struct device), GFP_KERNEL);
 205
 206         if (NULL == dev)
 207                 return -ENOMEM;
 208
 209         new_bus = kzalloc(sizeof(struct mii_bus), GFP_KERNEL);
 210
 211         if (NULL == new_bus) {
 212                 kfree(dev);
 213                 return -ENOMEM;
 214         }
 215         fixed = kzalloc(sizeof(struct fixed_info), GFP_KERNEL);
 216
 217         if (NULL == fixed) {
 218                 kfree(dev);
 219                 kfree(new_bus);
 220                 return -ENOMEM;
 221         }
 222
 223         fixed->regs = kzalloc(MII_REGS_NUM*sizeof(int), GFP_KERNEL);
 224         fixed->regs_num = MII_REGS_NUM;
 225         fixed->phy_status.speed = speed;
 226         fixed->phy_status.duplex = duplex;
 227         fixed->phy_status.link = 1;
 228
 229         new_bus->name = "Fixed MII Bus",
 230         new_bus->read = &fixed_mii_read,
 231         new_bus->write = &fixed_mii_write,
 232         new_bus->reset = &fixed_mii_reset,
 233
 234         /*set up workspace*/
 235         fixed_mdio_update_regs(fixed);
 236         new_bus->priv = fixed;
 237
 238         new_bus->dev = dev;
 239         dev_set_drvdata(dev, new_bus);
 240
 241         /* create phy_device and register it on the mdio bus */
 242         phydev = phy_device_create(new_bus, 0, 0);
 243
 244         /*
 245          Put the phydev pointer into the fixed pack so that bus read/write code could
 246          be able to access for instance attached netdev. Well it doesn't have to do
 247          so, only in case of utilizing user-specified link-update...
 248          */
 249         fixed->phydev = phydev;
 250
 251         if(NULL == phydev) {
 252                 err = -ENOMEM;
 253                 goto device_create_fail;
 254         }
 255
 256         phydev->irq = PHY_IGNORE_INTERRUPT;
 257         phydev->dev.bus = &mdio_bus_type;
 258
 259         if(number)
 260                 snprintf(phydev->dev.bus_id, BUS_ID_SIZE,
 261                                 "fixed_%d@%d:%d", number, speed, duplex);
 262         else
 263                 snprintf(phydev->dev.bus_id, BUS_ID_SIZE,
 264                                 "fixed@%d:%d", speed, duplex);
 265         phydev->bus = new_bus;
 266
 267         err = device_register(&phydev->dev);
 268         if(err) {
 269                 printk(KERN_ERR "Phy %s failed to register\n",
 270                                 phydev->dev.bus_id);
 271                 goto bus_register_fail;
 272         }
 273
 274         /*
 275            the mdio bus has phy_id match... In order not to do it
 276            artificially, we are binding the driver here by hand;
 277            it will be the same for all the fixed phys anyway.
 278          */
 279         phydev->dev.driver = &fixed_mdio_driver.driver;
 280
 281         err = phydev->dev.driver->probe(&phydev->dev);
 282         if(err < 0) {
 283                 printk(KERN_ERR "Phy %s: problems with fixed driver\n",phydev->dev.bus_id);
 284                 goto probe_fail;
 285         }
 286
 287         err = device_bind_driver(&phydev->dev);
 288         if (err)
 289                 goto probe_fail;
 290
 291         return 0;
 292
 293 probe_fail:
 294         device_unregister(&phydev->dev);
 295 bus_register_fail:
 296         kfree(phydev);
 297 device_create_fail:
 298         kfree(dev);
 299         kfree(new_bus);
 300         kfree(fixed);
 301
 302         return err;
 303 }
 304
 305
 306 MODULE_DESCRIPTION("Fixed PHY device & driver for PAL");
 307 MODULE_AUTHOR("Vitaly Bordug");
 308 MODULE_LICENSE("GPL");
 309
 310 static int __init fixed_init(void)
 311 {
 312 #if 0
 313         int ret;
 314         int duplex = 0;
 315 #endif
 316
 317         /* register on the bus... Not expected to be matched with anything there... */
 318         phy_driver_register(&fixed_mdio_driver);
 319
 320         /* So let the fun begin...
 321            We will create several mdio devices here, and will bound the upper
 322            driver to them.
 323
 324            Then the external software can lookup the phy bus by searching
 325            fixed@speed:duplex, e.g. fixed@100:1, to be connected to the
 326            virtual 100M Fdx phy.
 327
 328            In case several virtual PHYs required, the bus_id will be in form
 329            fixed_<num>@<speed>:<duplex>, which make it able even to define
 330            driver-specific link control callback, if for instance PHY is completely
 331            SW-driven.
 332
 333         */
 334
 335 #ifdef CONFIG_FIXED_MII_DUPLEX
 336 #if 0
 337         duplex = 1;
 338 #endif
 339 #endif
 340
 341 #ifdef CONFIG_FIXED_MII_100_FDX
 342         fixed_mdio_register_device(0, 100, 1);
 343 #endif
 344
 345 #ifdef CONFIG_FIXED_MII_10_FDX
 346         fixed_mdio_register_device(0, 10, 1);
 347 #endif
 348         return 0;
 349 }
 350
 351 static void __exit fixed_exit(void)
 352 {
 353         phy_driver_unregister(&fixed_mdio_driver);
 354         /* :WARNING:02/18/2006 04:32:40 AM:: Cleanup all the created stuff */
 355 }
 356
 357 module_init(fixed_init);
 358 module_exit(fixed_exit);