drivers/net/ethernet/broadcom/genet/bcmmii.c

   1 /*
   2  * Broadcom GENET MDIO routines
   3  *
   4  * Copyright (c) 2014-2017 Broadcom
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11
  12 #include <linux/types.h>
  13 #include <linux/delay.h>
  14 #include <linux/wait.h>
  15 #include <linux/mii.h>
  16 #include <linux/ethtool.h>
  17 #include <linux/bitops.h>
  18 #include <linux/netdevice.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/phy.h>
  21 #include <linux/phy_fixed.h>
  22 #include <linux/brcmphy.h>
  23 #include <linux/of.h>
  24 #include <linux/of_net.h>
  25 #include <linux/of_mdio.h>
  26 #include <linux/platform_data/bcmgenet.h>
  27
  28 #include "bcmgenet.h"
  29
  30 /* read a value from the MII */
  31 static int bcmgenet_mii_read(struct mii_bus *bus, int phy_id, int location)
  32 {
  33         int ret;
  34         struct net_device *dev = bus->priv;
  35         struct bcmgenet_priv *priv = netdev_priv(dev);
  36         u32 reg;
  37
  38         bcmgenet_umac_writel(priv, (MDIO_RD | (phy_id << MDIO_PMD_SHIFT) |
  39                              (location << MDIO_REG_SHIFT)), UMAC_MDIO_CMD);
  40         /* Start MDIO transaction*/
  41         reg = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
  42         reg |= MDIO_START_BUSY;
  43         bcmgenet_umac_writel(priv, reg, UMAC_MDIO_CMD);
  44         wait_event_timeout(priv->wq,
  45                            !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD)
  46                            & MDIO_START_BUSY),
  47                            HZ / 100);
  48         ret = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
  49
  50         /* Some broken devices are known not to release the line during
  51          * turn-around, e.g: Broadcom BCM53125 external switches, so check for
  52          * that condition here and ignore the MDIO controller read failure
  53          * indication.
  54          */
  55         if (!(bus->phy_ignore_ta_mask & 1 << phy_id) && (ret & MDIO_READ_FAIL))
  56                 return -EIO;
  57
  58         return ret & 0xffff;
  59 }
  60
  61 /* write a value to the MII */
  62 static int bcmgenet_mii_write(struct mii_bus *bus, int phy_id,
  63                               int location, u16 val)
  64 {
  65         struct net_device *dev = bus->priv;
  66         struct bcmgenet_priv *priv = netdev_priv(dev);
  67         u32 reg;
  68
  69         bcmgenet_umac_writel(priv, (MDIO_WR | (phy_id << MDIO_PMD_SHIFT) |
  70                              (location << MDIO_REG_SHIFT) | (0xffff & val)),
  71                              UMAC_MDIO_CMD);
  72         reg = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
  73         reg |= MDIO_START_BUSY;
  74         bcmgenet_umac_writel(priv, reg, UMAC_MDIO_CMD);
  75         wait_event_timeout(priv->wq,
  76                            !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD) &
  77                            MDIO_START_BUSY),
  78                            HZ / 100);
  79
  80         return 0;
  81 }
  82
  83 /* setup netdev link state when PHY link status change and
  84  * update UMAC and RGMII block when link up
  85  */
  86 void bcmgenet_mii_setup(struct net_device *dev)
  87 {
  88         struct bcmgenet_priv *priv = netdev_priv(dev);
  89         struct phy_device *phydev = priv->phydev;
  90         u32 reg, cmd_bits = 0;
  91         bool status_changed = false;
  92
  93         if (priv->old_link != phydev->link) {
  94                 status_changed = true;
  95                 priv->old_link = phydev->link;
  96         }
  97
  98         if (phydev->link) {
  99                 /* check speed/duplex/pause changes */
 100                 if (priv->old_speed != phydev->speed) {
 101                         status_changed = true;
 102                         priv->old_speed = phydev->speed;
 103                 }
 104
 105                 if (priv->old_duplex != phydev->duplex) {
 106                         status_changed = true;
 107                         priv->old_duplex = phydev->duplex;
 108                 }
 109
 110                 if (priv->old_pause != phydev->pause) {
 111                         status_changed = true;
 112                         priv->old_pause = phydev->pause;
 113                 }
 114
 115                 /* done if nothing has changed */
 116                 if (!status_changed)
 117                         return;
 118
 119                 /* speed */
 120                 if (phydev->speed == SPEED_1000)
 121                         cmd_bits = UMAC_SPEED_1000;
 122                 else if (phydev->speed == SPEED_100)
 123                         cmd_bits = UMAC_SPEED_100;
 124                 else
 125                         cmd_bits = UMAC_SPEED_10;
 126                 cmd_bits <<= CMD_SPEED_SHIFT;
 127
 128                 /* duplex */
 129                 if (phydev->duplex != DUPLEX_FULL)
 130                         cmd_bits |= CMD_HD_EN;
 131
 132                 /* pause capability */
 133                 if (!phydev->pause)
 134                         cmd_bits |= CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE;
 135
 136                 /*
 137                  * Program UMAC and RGMII block based on established
 138                  * link speed, duplex, and pause. The speed set in
 139                  * umac->cmd tell RGMII block which clock to use for
 140                  * transmit -- 25MHz(100Mbps) or 125MHz(1Gbps).
 141                  * Receive clock is provided by the PHY.
 142                  */
 143                 reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
 144                 reg &= ~OOB_DISABLE;
 145                 reg |= RGMII_LINK;
 146                 bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
 147
 148                 reg = bcmgenet_umac_readl(priv, UMAC_CMD);
 149                 reg &= ~((CMD_SPEED_MASK << CMD_SPEED_SHIFT) |
 150                                CMD_HD_EN |
 151                                CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE);
 152                 reg |= cmd_bits;
 153                 bcmgenet_umac_writel(priv, reg, UMAC_CMD);
 154         } else {
 155                 /* done if nothing has changed */
 156                 if (!status_changed)
 157                         return;
 158
 159                 /* needed for MoCA fixed PHY to reflect correct link status */
 160                 netif_carrier_off(dev);
 161         }
 162
 163         phy_print_status(phydev);
 164 }
 165
 166
 167 static int bcmgenet_fixed_phy_link_update(struct net_device *dev,
 168                                           struct fixed_phy_status *status)
 169 {
 170         if (dev && dev->phydev && status)
 171                 status->link = dev->phydev->link;
 172
 173         return 0;
 174 }
 175
 176 /* Perform a voluntary PHY software reset, since the EPHY is very finicky about
 177  * not doing it and will start corrupting packets
 178  */
 179 void bcmgenet_mii_reset(struct net_device *dev)
 180 {
 181         struct bcmgenet_priv *priv = netdev_priv(dev);
 182
 183         if (GENET_IS_V4(priv))
 184                 return;
 185
 186         if (priv->phydev) {
 187                 phy_init_hw(priv->phydev);
 188                 phy_start_aneg(priv->phydev);
 189         }
 190 }
 191
 192 void bcmgenet_phy_power_set(struct net_device *dev, bool enable)
 193 {
 194         struct bcmgenet_priv *priv = netdev_priv(dev);
 195         u32 reg = 0;
 196
 197         /* EXT_GPHY_CTRL is only valid for GENETv4 and onward */
 198         if (GENET_IS_V4(priv)) {
 199                 reg = bcmgenet_ext_readl(priv, EXT_GPHY_CTRL);
 200                 if (enable) {
 201                         reg &= ~EXT_CK25_DIS;
 202                         bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
 203                         mdelay(1);
 204
 205                         reg &= ~(EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN);
 206                         reg |= EXT_GPHY_RESET;
 207                         bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
 208                         mdelay(1);
 209
 210                         reg &= ~EXT_GPHY_RESET;
 211                 } else {
 212                         reg |= EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN |
 213                                EXT_GPHY_RESET;
 214                         bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
 215                         mdelay(1);
 216                         reg |= EXT_CK25_DIS;
 217                 }
 218                 bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
 219                 udelay(60);
 220         } else {
 221                 mdelay(1);
 222         }
 223 }
 224
 225 static void bcmgenet_moca_phy_setup(struct bcmgenet_priv *priv)
 226 {
 227         u32 reg;
 228
 229         if (!GENET_IS_V5(priv)) {
 230                 /* Speed settings are set in bcmgenet_mii_setup() */
 231                 reg = bcmgenet_sys_readl(priv, SYS_PORT_CTRL);
 232                 reg |= LED_ACT_SOURCE_MAC;
 233                 bcmgenet_sys_writel(priv, reg, SYS_PORT_CTRL);
 234         }
 235
 236         if (priv->hw_params->flags & GENET_HAS_MOCA_LINK_DET)
 237                 fixed_phy_set_link_update(priv->phydev,
 238                                           bcmgenet_fixed_phy_link_update);
 239 }
 240
 241 int bcmgenet_mii_config(struct net_device *dev, bool init)
 242 {
 243         struct bcmgenet_priv *priv = netdev_priv(dev);
 244         struct phy_device *phydev = priv->phydev;
 245         struct device *kdev = &priv->pdev->dev;
 246         const char *phy_name = NULL;
 247         u32 id_mode_dis = 0;
 248         u32 port_ctrl;
 249         u32 reg;
 250
 251         priv->ext_phy = !priv->internal_phy &&
 252                         (priv->phy_interface != PHY_INTERFACE_MODE_MOCA);
 253
 254         switch (priv->phy_interface) {
 255         case PHY_INTERFACE_MODE_INTERNAL:
 256         case PHY_INTERFACE_MODE_MOCA:
 257                 /* Irrespective of the actually configured PHY speed (100 or
 258                  * 1000) GENETv4 only has an internal GPHY so we will just end
 259                  * up masking the Gigabit features from what we support, not
 260                  * switching to the EPHY
 261                  */
 262                 if (GENET_IS_V4(priv))
 263                         port_ctrl = PORT_MODE_INT_GPHY;
 264                 else
 265                         port_ctrl = PORT_MODE_INT_EPHY;
 266
 267                 bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
 268
 269                 if (priv->internal_phy) {
 270                         phy_name = "internal PHY";
 271                 } else if (priv->phy_interface == PHY_INTERFACE_MODE_MOCA) {
 272                         phy_name = "MoCA";
 273                         bcmgenet_moca_phy_setup(priv);
 274                 }
 275                 break;
 276
 277         case PHY_INTERFACE_MODE_MII:
 278                 phy_name = "external MII";
 279                 phydev->supported &= PHY_BASIC_FEATURES;
 280                 bcmgenet_sys_writel(priv,
 281                                     PORT_MODE_EXT_EPHY, SYS_PORT_CTRL);
 282                 break;
 283
 284         case PHY_INTERFACE_MODE_REVMII:
 285                 phy_name = "external RvMII";
 286                 /* of_mdiobus_register took care of reading the 'max-speed'
 287                  * PHY property for us, effectively limiting the PHY supported
 288                  * capabilities, use that knowledge to also configure the
 289                  * Reverse MII interface correctly.
 290                  */
 291                 if ((priv->phydev->supported & PHY_BASIC_FEATURES) ==
 292                                 PHY_BASIC_FEATURES)
 293                         port_ctrl = PORT_MODE_EXT_RVMII_25;
 294                 else
 295                         port_ctrl = PORT_MODE_EXT_RVMII_50;
 296                 bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
 297                 break;
 298
 299         case PHY_INTERFACE_MODE_RGMII:
 300                 /* RGMII_NO_ID: TXC transitions at the same time as TXD
 301                  *              (requires PCB or receiver-side delay)
 302                  * RGMII:       Add 2ns delay on TXC (90 degree shift)
 303                  *
 304                  * ID is implicitly disabled for 100Mbps (RG)MII operation.
 305                  */
 306                 id_mode_dis = BIT(16);
 307                 /* fall through */
 308         case PHY_INTERFACE_MODE_RGMII_TXID:
 309                 if (id_mode_dis)
 310                         phy_name = "external RGMII (no delay)";
 311                 else
 312                         phy_name = "external RGMII (TX delay)";
 313                 bcmgenet_sys_writel(priv,
 314                                     PORT_MODE_EXT_GPHY, SYS_PORT_CTRL);
 315                 break;
 316         default:
 317                 dev_err(kdev, "unknown phy mode: %d\n", priv->phy_interface);
 318                 return -EINVAL;
 319         }
 320
 321         /* This is an external PHY (xMII), so we need to enable the RGMII
 322          * block for the interface to work
 323          */
 324         if (priv->ext_phy) {
 325                 reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
 326                 reg |= RGMII_MODE_EN | id_mode_dis;
 327                 bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
 328         }
 329
 330         if (init)
 331                 dev_info(kdev, "configuring instance for %s\n", phy_name);
 332
 333         return 0;
 334 }
 335
 336 int bcmgenet_mii_probe(struct net_device *dev)
 337 {
 338         struct bcmgenet_priv *priv = netdev_priv(dev);
 339         struct device_node *dn = priv->pdev->dev.of_node;
 340         struct phy_device *phydev;
 341         u32 phy_flags;
 342         int ret;
 343
 344         /* Communicate the integrated PHY revision */
 345         phy_flags = priv->gphy_rev;
 346
 347         /* Initialize link state variables that bcmgenet_mii_setup() uses */
 348         priv->old_link = -1;
 349         priv->old_speed = -1;
 350         priv->old_duplex = -1;
 351         priv->old_pause = -1;
 352
 353         if (dn) {
 354                 phydev = of_phy_connect(dev, priv->phy_dn, bcmgenet_mii_setup,
 355                                         phy_flags, priv->phy_interface);
 356                 if (!phydev) {
 357                         pr_err("could not attach to PHY\n");
 358                         return -ENODEV;
 359                 }
 360         } else {
 361                 phydev = priv->phydev;
 362                 phydev->dev_flags = phy_flags;
 363
 364                 ret = phy_connect_direct(dev, phydev, bcmgenet_mii_setup,
 365                                          priv->phy_interface);
 366                 if (ret) {
 367                         pr_err("could not attach to PHY\n");
 368                         return -ENODEV;
 369                 }
 370         }
 371
 372         priv->phydev = phydev;
 373
 374         /* Configure port multiplexer based on what the probed PHY device since
 375          * reading the 'max-speed' property determines the maximum supported
 376          * PHY speed which is needed for bcmgenet_mii_config() to configure
 377          * things appropriately.
 378          */
 379         ret = bcmgenet_mii_config(dev, true);
 380         if (ret) {
 381                 phy_disconnect(priv->phydev);
 382                 return ret;
 383         }
 384
 385         phydev->advertising = phydev->supported;
 386
 387         /* The internal PHY has its link interrupts routed to the
 388          * Ethernet MAC ISRs
 389          */
 390         if (priv->internal_phy)
 391                 priv->phydev->irq = PHY_IGNORE_INTERRUPT;
 392
 393         return 0;
 394 }
 395
 396 /* Workaround for integrated BCM7xxx Gigabit PHYs which have a problem with
 397  * their internal MDIO management controller making them fail to successfully
 398  * be read from or written to for the first transaction.  We insert a dummy
 399  * BMSR read here to make sure that phy_get_device() and get_phy_id() can
 400  * correctly read the PHY MII_PHYSID1/2 registers and successfully register a
 401  * PHY device for this peripheral.
 402  *
 403  * Once the PHY driver is registered, we can workaround subsequent reads from
 404  * there (e.g: during system-wide power management).
 405  *
 406  * bus->reset is invoked before mdiobus_scan during mdiobus_register and is
 407  * therefore the right location to stick that workaround. Since we do not want
 408  * to read from non-existing PHYs, we either use bus->phy_mask or do a manual
 409  * Device Tree scan to limit the search area.
 410  */
 411 static int bcmgenet_mii_bus_reset(struct mii_bus *bus)
 412 {
 413         struct net_device *dev = bus->priv;
 414         struct bcmgenet_priv *priv = netdev_priv(dev);
 415         struct device_node *np = priv->mdio_dn;
 416         struct device_node *child = NULL;
 417         u32 read_mask = 0;
 418         int addr = 0;
 419
 420         if (!np) {
 421                 read_mask = 1 << priv->phy_addr;
 422         } else {
 423                 for_each_available_child_of_node(np, child) {
 424                         addr = of_mdio_parse_addr(&dev->dev, child);
 425                         if (addr < 0)
 426                                 continue;
 427
 428                         read_mask |= 1 << addr;
 429                 }
 430         }
 431
 432         for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 433                 if (read_mask & 1 << addr) {
 434                         dev_dbg(&dev->dev, "Workaround for PHY @ %d\n", addr);
 435                         mdiobus_read(bus, addr, MII_BMSR);
 436                 }
 437         }
 438
 439         return 0;
 440 }
 441
 442 static int bcmgenet_mii_alloc(struct bcmgenet_priv *priv)
 443 {
 444         struct mii_bus *bus;
 445
 446         if (priv->mii_bus)
 447                 return 0;
 448
 449         priv->mii_bus = mdiobus_alloc();
 450         if (!priv->mii_bus) {
 451                 pr_err("failed to allocate\n");
 452                 return -ENOMEM;
 453         }
 454
 455         bus = priv->mii_bus;
 456         bus->priv = priv->dev;
 457         bus->name = "bcmgenet MII bus";
 458         bus->parent = &priv->pdev->dev;
 459         bus->read = bcmgenet_mii_read;
 460         bus->write = bcmgenet_mii_write;
 461         bus->reset = bcmgenet_mii_bus_reset;
 462         snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d",
 463                  priv->pdev->name, priv->pdev->id);
 464
 465         return 0;
 466 }
 467
 468 static int bcmgenet_mii_of_init(struct bcmgenet_priv *priv)
 469 {
 470         struct device_node *dn = priv->pdev->dev.of_node;
 471         struct device *kdev = &priv->pdev->dev;
 472         struct phy_device *phydev = NULL;
 473         char *compat;
 474         int phy_mode;
 475         int ret;
 476
 477         compat = kasprintf(GFP_KERNEL, "brcm,genet-mdio-v%d", priv->version);
 478         if (!compat)
 479                 return -ENOMEM;
 480
 481         priv->mdio_dn = of_find_compatible_node(dn, NULL, compat);
 482         kfree(compat);
 483         if (!priv->mdio_dn) {
 484                 dev_err(kdev, "unable to find MDIO bus node\n");
 485                 return -ENODEV;
 486         }
 487
 488         ret = of_mdiobus_register(priv->mii_bus, priv->mdio_dn);
 489         if (ret) {
 490                 dev_err(kdev, "failed to register MDIO bus\n");
 491                 return ret;
 492         }
 493
 494         /* Fetch the PHY phandle */
 495         priv->phy_dn = of_parse_phandle(dn, "phy-handle", 0);
 496
 497         /* In the case of a fixed PHY, the DT node associated
 498          * to the PHY is the Ethernet MAC DT node.
 499          */
 500         if (!priv->phy_dn && of_phy_is_fixed_link(dn)) {
 501                 ret = of_phy_register_fixed_link(dn);
 502                 if (ret)
 503                         return ret;
 504
 505                 priv->phy_dn = of_node_get(dn);
 506         }
 507
 508         /* Get the link mode */
 509         phy_mode = of_get_phy_mode(dn);
 510         if (phy_mode < 0) {
 511                 dev_err(kdev, "invalid PHY mode property\n");
 512                 return phy_mode;
 513         }
 514
 515         priv->phy_interface = phy_mode;
 516
 517         /* We need to specifically look up whether this PHY interface is internal
 518          * or not *before* we even try to probe the PHY driver over MDIO as we
 519          * may have shut down the internal PHY for power saving purposes.
 520          */
 521         if (priv->phy_interface == PHY_INTERFACE_MODE_INTERNAL)
 522                 priv->internal_phy = true;
 523
 524         /* Make sure we initialize MoCA PHYs with a link down */
 525         if (phy_mode == PHY_INTERFACE_MODE_MOCA) {
 526                 phydev = of_phy_find_device(dn);
 527                 if (phydev) {
 528                         phydev->link = 0;
 529                         put_device(&phydev->mdio.dev);
 530                 }
 531         }
 532
 533         return 0;
 534 }
 535
 536 static int bcmgenet_mii_pd_init(struct bcmgenet_priv *priv)
 537 {
 538         struct device *kdev = &priv->pdev->dev;
 539         struct bcmgenet_platform_data *pd = kdev->platform_data;
 540         struct mii_bus *mdio = priv->mii_bus;
 541         struct phy_device *phydev;
 542         int ret;
 543
 544         if (pd->phy_interface != PHY_INTERFACE_MODE_MOCA && pd->mdio_enabled) {
 545                 /*
 546                  * Internal or external PHY with MDIO access
 547                  */
 548                 if (pd->phy_address >= 0 && pd->phy_address < PHY_MAX_ADDR)
 549                         mdio->phy_mask = ~(1 << pd->phy_address);
 550                 else
 551                         mdio->phy_mask = 0;
 552
 553                 ret = mdiobus_register(mdio);
 554                 if (ret) {
 555                         dev_err(kdev, "failed to register MDIO bus\n");
 556                         return ret;
 557                 }
 558
 559                 if (pd->phy_address >= 0 && pd->phy_address < PHY_MAX_ADDR)
 560                         phydev = mdiobus_get_phy(mdio, pd->phy_address);
 561                 else
 562                         phydev = phy_find_first(mdio);
 563
 564                 if (!phydev) {
 565                         dev_err(kdev, "failed to register PHY device\n");
 566                         mdiobus_unregister(mdio);
 567                         return -ENODEV;
 568                 }
 569         } else {
 570                 /*
 571                  * MoCA port or no MDIO access.
 572                  * Use fixed PHY to represent the link layer.
 573                  */
 574                 struct fixed_phy_status fphy_status = {
 575                         .link = 1,
 576                         .speed = pd->phy_speed,
 577                         .duplex = pd->phy_duplex,
 578                         .pause = 0,
 579                         .asym_pause = 0,
 580                 };
 581
 582                 phydev = fixed_phy_register(PHY_POLL, &fphy_status, -1, NULL);
 583                 if (!phydev || IS_ERR(phydev)) {
 584                         dev_err(kdev, "failed to register fixed PHY device\n");
 585                         return -ENODEV;
 586                 }
 587
 588                 /* Make sure we initialize MoCA PHYs with a link down */
 589                 phydev->link = 0;
 590
 591         }
 592
 593         priv->phydev = phydev;
 594         priv->phy_interface = pd->phy_interface;
 595
 596         return 0;
 597 }
 598
 599 static int bcmgenet_mii_bus_init(struct bcmgenet_priv *priv)
 600 {
 601         struct device_node *dn = priv->pdev->dev.of_node;
 602
 603         if (dn)
 604                 return bcmgenet_mii_of_init(priv);
 605         else
 606                 return bcmgenet_mii_pd_init(priv);
 607 }
 608
 609 int bcmgenet_mii_init(struct net_device *dev)
 610 {
 611         struct bcmgenet_priv *priv = netdev_priv(dev);
 612         struct device_node *dn = priv->pdev->dev.of_node;
 613         int ret;
 614
 615         ret = bcmgenet_mii_alloc(priv);
 616         if (ret)
 617                 return ret;
 618
 619         ret = bcmgenet_mii_bus_init(priv);
 620         if (ret)
 621                 goto out;
 622
 623         return 0;
 624
 625 out:
 626         if (of_phy_is_fixed_link(dn))
 627                 of_phy_deregister_fixed_link(dn);
 628         of_node_put(priv->phy_dn);
 629         mdiobus_unregister(priv->mii_bus);
 630         mdiobus_free(priv->mii_bus);
 631         return ret;
 632 }
 633
 634 void bcmgenet_mii_exit(struct net_device *dev)
 635 {
 636         struct bcmgenet_priv *priv = netdev_priv(dev);
 637         struct device_node *dn = priv->pdev->dev.of_node;
 638
 639         if (of_phy_is_fixed_link(dn))
 640                 of_phy_deregister_fixed_link(dn);
 641         of_node_put(priv->phy_dn);
 642         mdiobus_unregister(priv->mii_bus);
 643         mdiobus_free(priv->mii_bus);
 644 }