drivers/net/phy/fixed_phy.c

   1 /*
   2  * Fixed MDIO bus (MDIO bus emulation with fixed PHYs)
   3  *
   4  * Author: Vitaly Bordug <vbordug@ru.mvista.com>
   5  *         Anton Vorontsov <avorontsov@ru.mvista.com>
   6  *
   7  * Copyright (c) 2006-2007 MontaVista Software, Inc.
   8  *
   9  * This program is free software; you can redistribute  it and/or modify it
  10  * under  the terms of  the GNU General  Public License as published by the
  11  * Free Software Foundation;  either version 2 of the  License, or (at your
  12  * option) any later version.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/list.h>
  19 #include <linux/mii.h>
  20 #include <linux/phy.h>
  21 #include <linux/phy_fixed.h>
  22 #include <linux/err.h>
  23 #include <linux/slab.h>
  24 #include <linux/of.h>
  25
  26 #define MII_REGS_NUM 29
  27
  28 struct fixed_mdio_bus {
  29         int irqs[PHY_MAX_ADDR];
  30         struct mii_bus *mii_bus;
  31         struct list_head phys;
  32 };
  33
  34 struct fixed_phy {
  35         int addr;
  36         u16 regs[MII_REGS_NUM];
  37         struct phy_device *phydev;
  38         struct fixed_phy_status status;
  39         int (*link_update)(struct net_device *, struct fixed_phy_status *);
  40         struct list_head node;
  41 };
  42
  43 static struct platform_device *pdev;
  44 static struct fixed_mdio_bus platform_fmb = {
  45         .phys = LIST_HEAD_INIT(platform_fmb.phys),
  46 };
  47
  48 static int fixed_phy_update_regs(struct fixed_phy *fp)
  49 {
  50         u16 bmsr = BMSR_ANEGCAPABLE;
  51         u16 bmcr = 0;
  52         u16 lpagb = 0;
  53         u16 lpa = 0;
  54
  55         if (fp->status.duplex) {
  56                 bmcr |= BMCR_FULLDPLX;
  57
  58                 switch (fp->status.speed) {
  59                 case 1000:
  60                         bmsr |= BMSR_ESTATEN;
  61                         bmcr |= BMCR_SPEED1000;
  62                         lpagb |= LPA_1000FULL;
  63                         break;
  64                 case 100:
  65                         bmsr |= BMSR_100FULL;
  66                         bmcr |= BMCR_SPEED100;
  67                         lpa |= LPA_100FULL;
  68                         break;
  69                 case 10:
  70                         bmsr |= BMSR_10FULL;
  71                         lpa |= LPA_10FULL;
  72                         break;
  73                 default:
  74                         pr_warn("fixed phy: unknown speed\n");
  75                         return -EINVAL;
  76                 }
  77         } else {
  78                 switch (fp->status.speed) {
  79                 case 1000:
  80                         bmsr |= BMSR_ESTATEN;
  81                         bmcr |= BMCR_SPEED1000;
  82                         lpagb |= LPA_1000HALF;
  83                         break;
  84                 case 100:
  85                         bmsr |= BMSR_100HALF;
  86                         bmcr |= BMCR_SPEED100;
  87                         lpa |= LPA_100HALF;
  88                         break;
  89                 case 10:
  90                         bmsr |= BMSR_10HALF;
  91                         lpa |= LPA_10HALF;
  92                         break;
  93                 default:
  94                         pr_warn("fixed phy: unknown speed\n");
  95                         return -EINVAL;
  96                 }
  97         }
  98
  99         if (fp->status.link)
 100                 bmsr |= BMSR_LSTATUS | BMSR_ANEGCOMPLETE;
 101
 102         if (fp->status.pause)
 103                 lpa |= LPA_PAUSE_CAP;
 104
 105         if (fp->status.asym_pause)
 106                 lpa |= LPA_PAUSE_ASYM;
 107
 108         fp->regs[MII_PHYSID1] = 0;
 109         fp->regs[MII_PHYSID2] = 0;
 110
 111         fp->regs[MII_BMSR] = bmsr;
 112         fp->regs[MII_BMCR] = bmcr;
 113         fp->regs[MII_LPA] = lpa;
 114         fp->regs[MII_STAT1000] = lpagb;
 115
 116         return 0;
 117 }
 118
 119 static int fixed_mdio_read(struct mii_bus *bus, int phy_addr, int reg_num)
 120 {
 121         struct fixed_mdio_bus *fmb = bus->priv;
 122         struct fixed_phy *fp;
 123
 124         if (reg_num >= MII_REGS_NUM)
 125                 return -1;
 126
 127         /* We do not support emulating Clause 45 over Clause 22 register reads
 128          * return an error instead of bogus data.
 129          */
 130         switch (reg_num) {
 131         case MII_MMD_CTRL:
 132         case MII_MMD_DATA:
 133                 return -1;
 134         default:
 135                 break;
 136         }
 137
 138         list_for_each_entry(fp, &fmb->phys, node) {
 139                 if (fp->addr == phy_addr) {
 140                         /* Issue callback if user registered it. */
 141                         if (fp->link_update) {
 142                                 fp->link_update(fp->phydev->attached_dev,
 143                                                 &fp->status);
 144                                 fixed_phy_update_regs(fp);
 145                         }
 146                         return fp->regs[reg_num];
 147                 }
 148         }
 149
 150         return 0xFFFF;
 151 }
 152
 153 static int fixed_mdio_write(struct mii_bus *bus, int phy_addr, int reg_num,
 154                             u16 val)
 155 {
 156         return 0;
 157 }
 158
 159 /*
 160  * If something weird is required to be done with link/speed,
 161  * network driver is able to assign a function to implement this.
 162  * May be useful for PHY's that need to be software-driven.
 163  */
 164 int fixed_phy_set_link_update(struct phy_device *phydev,
 165                               int (*link_update)(struct net_device *,
 166                                                  struct fixed_phy_status *))
 167 {
 168         struct fixed_mdio_bus *fmb = &platform_fmb;
 169         struct fixed_phy *fp;
 170
 171         if (!phydev || !phydev->bus)
 172                 return -EINVAL;
 173
 174         list_for_each_entry(fp, &fmb->phys, node) {
 175                 if (fp->addr == phydev->addr) {
 176                         fp->link_update = link_update;
 177                         fp->phydev = phydev;
 178                         return 0;
 179                 }
 180         }
 181
 182         return -ENOENT;
 183 }
 184 EXPORT_SYMBOL_GPL(fixed_phy_set_link_update);
 185
 186 int fixed_phy_update_state(struct phy_device *phydev,
 187                            const struct fixed_phy_status *status,
 188                            const struct fixed_phy_status *changed)
 189 {
 190         struct fixed_mdio_bus *fmb = &platform_fmb;
 191         struct fixed_phy *fp;
 192
 193         if (!phydev || !phydev->bus)
 194                 return -EINVAL;
 195
 196         list_for_each_entry(fp, &fmb->phys, node) {
 197                 if (fp->addr == phydev->addr) {
 198 #define _UPD(x) if (changed->x) \
 199         fp->status.x = status->x
 200                         _UPD(link);
 201                         _UPD(speed);
 202                         _UPD(duplex);
 203                         _UPD(pause);
 204                         _UPD(asym_pause);
 205 #undef _UPD
 206                         fixed_phy_update_regs(fp);
 207                         return 0;
 208                 }
 209         }
 210
 211         return -ENOENT;
 212 }
 213 EXPORT_SYMBOL(fixed_phy_update_state);
 214
 215 int fixed_phy_add(unsigned int irq, int phy_addr,
 216                   struct fixed_phy_status *status)
 217 {
 218         int ret;
 219         struct fixed_mdio_bus *fmb = &platform_fmb;
 220         struct fixed_phy *fp;
 221
 222         fp = kzalloc(sizeof(*fp), GFP_KERNEL);
 223         if (!fp)
 224                 return -ENOMEM;
 225
 226         memset(fp->regs, 0xFF,  sizeof(fp->regs[0]) * MII_REGS_NUM);
 227
 228         fmb->irqs[phy_addr] = irq;
 229
 230         fp->addr = phy_addr;
 231         fp->status = *status;
 232
 233         ret = fixed_phy_update_regs(fp);
 234         if (ret)
 235                 goto err_regs;
 236
 237         list_add_tail(&fp->node, &fmb->phys);
 238
 239         return 0;
 240
 241 err_regs:
 242         kfree(fp);
 243         return ret;
 244 }
 245 EXPORT_SYMBOL_GPL(fixed_phy_add);
 246
 247 void fixed_phy_del(int phy_addr)
 248 {
 249         struct fixed_mdio_bus *fmb = &platform_fmb;
 250         struct fixed_phy *fp, *tmp;
 251
 252         list_for_each_entry_safe(fp, tmp, &fmb->phys, node) {
 253                 if (fp->addr == phy_addr) {
 254                         list_del(&fp->node);
 255                         kfree(fp);
 256                         return;
 257                 }
 258         }
 259 }
 260 EXPORT_SYMBOL_GPL(fixed_phy_del);
 261
 262 static int phy_fixed_addr;
 263 static DEFINE_SPINLOCK(phy_fixed_addr_lock);
 264
 265 struct phy_device *fixed_phy_register(unsigned int irq,
 266                                       struct fixed_phy_status *status,
 267                                       struct device_node *np)
 268 {
 269         struct fixed_mdio_bus *fmb = &platform_fmb;
 270         struct phy_device *phy;
 271         int phy_addr;
 272         int ret;
 273
 274         /* Get the next available PHY address, up to PHY_MAX_ADDR */
 275         spin_lock(&phy_fixed_addr_lock);
 276         if (phy_fixed_addr == PHY_MAX_ADDR) {
 277                 spin_unlock(&phy_fixed_addr_lock);
 278                 return ERR_PTR(-ENOSPC);
 279         }
 280         phy_addr = phy_fixed_addr++;
 281         spin_unlock(&phy_fixed_addr_lock);
 282
 283         ret = fixed_phy_add(PHY_POLL, phy_addr, status);
 284         if (ret < 0)
 285                 return ERR_PTR(ret);
 286
 287         phy = get_phy_device(fmb->mii_bus, phy_addr, false);
 288         if (!phy || IS_ERR(phy)) {
 289                 fixed_phy_del(phy_addr);
 290                 return ERR_PTR(-EINVAL);
 291         }
 292
 293         of_node_get(np);
 294         phy->dev.of_node = np;
 295
 296         ret = phy_device_register(phy);
 297         if (ret) {
 298                 phy_device_free(phy);
 299                 of_node_put(np);
 300                 fixed_phy_del(phy_addr);
 301                 return ERR_PTR(ret);
 302         }
 303
 304         return phy;
 305 }
 306 EXPORT_SYMBOL_GPL(fixed_phy_register);
 307
 308 static int __init fixed_mdio_bus_init(void)
 309 {
 310         struct fixed_mdio_bus *fmb = &platform_fmb;
 311         int ret;
 312
 313         pdev = platform_device_register_simple("Fixed MDIO bus", 0, NULL, 0);
 314         if (IS_ERR(pdev)) {
 315                 ret = PTR_ERR(pdev);
 316                 goto err_pdev;
 317         }
 318
 319         fmb->mii_bus = mdiobus_alloc();
 320         if (fmb->mii_bus == NULL) {
 321                 ret = -ENOMEM;
 322                 goto err_mdiobus_reg;
 323         }
 324
 325         snprintf(fmb->mii_bus->id, MII_BUS_ID_SIZE, "fixed-0");
 326         fmb->mii_bus->name = "Fixed MDIO Bus";
 327         fmb->mii_bus->priv = fmb;
 328         fmb->mii_bus->parent = &pdev->dev;
 329         fmb->mii_bus->read = &fixed_mdio_read;
 330         fmb->mii_bus->write = &fixed_mdio_write;
 331         fmb->mii_bus->irq = fmb->irqs;
 332
 333         ret = mdiobus_register(fmb->mii_bus);
 334         if (ret)
 335                 goto err_mdiobus_alloc;
 336
 337         return 0;
 338
 339 err_mdiobus_alloc:
 340         mdiobus_free(fmb->mii_bus);
 341 err_mdiobus_reg:
 342         platform_device_unregister(pdev);
 343 err_pdev:
 344         return ret;
 345 }
 346 module_init(fixed_mdio_bus_init);
 347
 348 static void __exit fixed_mdio_bus_exit(void)
 349 {
 350         struct fixed_mdio_bus *fmb = &platform_fmb;
 351         struct fixed_phy *fp, *tmp;
 352
 353         mdiobus_unregister(fmb->mii_bus);
 354         mdiobus_free(fmb->mii_bus);
 355         platform_device_unregister(pdev);
 356
 357         list_for_each_entry_safe(fp, tmp, &fmb->phys, node) {
 358                 list_del(&fp->node);
 359                 kfree(fp);
 360         }
 361 }
 362 module_exit(fixed_mdio_bus_exit);
 363
 364 MODULE_DESCRIPTION("Fixed MDIO bus (MDIO bus emulation with fixed PHYs)");
 365 MODULE_AUTHOR("Vitaly Bordug");
 366 MODULE_LICENSE("GPL");