drivers/of/of_mdio.c

   1 /*
   2  * OF helpers for the MDIO (Ethernet PHY) API
   3  *
   4  * Copyright (c) 2009 Secret Lab Technologies, Ltd.
   5  *
   6  * This file is released under the GPLv2
   7  *
   8  * This file provides helper functions for extracting PHY device information
   9  * out of the OpenFirmware device tree and using it to populate an mii_bus.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/device.h>
  14 #include <linux/netdevice.h>
  15 #include <linux/err.h>
  16 #include <linux/phy.h>
  17 #include <linux/phy_fixed.h>
  18 #include <linux/of.h>
  19 #include <linux/of_gpio.h>
  20 #include <linux/of_irq.h>
  21 #include <linux/of_mdio.h>
  22 #include <linux/module.h>
  23
  24 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
  25 MODULE_LICENSE("GPL");
  26
  27 /* Extract the clause 22 phy ID from the compatible string of the form
  28  * ethernet-phy-idAAAA.BBBB */
  29 static int of_get_phy_id(struct device_node *device, u32 *phy_id)
  30 {
  31         struct property *prop;
  32         const char *cp;
  33         unsigned int upper, lower;
  34
  35         of_property_for_each_string(device, "compatible", prop, cp) {
  36                 if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
  37                         *phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
  38                         return 0;
  39                 }
  40         }
  41         return -EINVAL;
  42 }
  43
  44 static int of_mdiobus_register_phy(struct mii_bus *mdio, struct device_node *child,
  45                                    u32 addr)
  46 {
  47         struct phy_device *phy;
  48         bool is_c45;
  49         int rc;
  50         u32 phy_id;
  51
  52         is_c45 = of_device_is_compatible(child,
  53                                          "ethernet-phy-ieee802.3-c45");
  54
  55         if (!is_c45 && !of_get_phy_id(child, &phy_id))
  56                 phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
  57         else
  58                 phy = get_phy_device(mdio, addr, is_c45);
  59         if (IS_ERR_OR_NULL(phy))
  60                 return 1;
  61
  62         rc = irq_of_parse_and_map(child, 0);
  63         if (rc > 0) {
  64                 phy->irq = rc;
  65                 mdio->irq[addr] = rc;
  66         } else {
  67                 phy->irq = mdio->irq[addr];
  68         }
  69
  70         if (of_property_read_bool(child, "broken-turn-around"))
  71                 mdio->phy_ignore_ta_mask |= 1 << addr;
  72
  73         /* Associate the OF node with the device structure so it
  74          * can be looked up later */
  75         of_node_get(child);
  76         phy->mdio.dev.of_node = child;
  77
  78         /* All data is now stored in the phy struct;
  79          * register it */
  80         rc = phy_device_register(phy);
  81         if (rc) {
  82                 phy_device_free(phy);
  83                 of_node_put(child);
  84                 return 1;
  85         }
  86
  87         dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
  88                 child->name, addr);
  89
  90         return 0;
  91 }
  92
  93 static int of_mdiobus_register_device(struct mii_bus *mdio,
  94                                       struct device_node *child,
  95                                       u32 addr)
  96 {
  97         struct mdio_device *mdiodev;
  98         int rc;
  99
 100         mdiodev = mdio_device_create(mdio, addr);
 101         if (IS_ERR(mdiodev))
 102                 return 1;
 103
 104         /* Associate the OF node with the device structure so it
 105          * can be looked up later.
 106          */
 107         of_node_get(child);
 108         mdiodev->dev.of_node = child;
 109
 110         /* All data is now stored in the mdiodev struct; register it. */
 111         rc = mdio_device_register(mdiodev);
 112         if (rc) {
 113                 mdio_device_free(mdiodev);
 114                 of_node_put(child);
 115                 return 1;
 116         }
 117
 118         dev_dbg(&mdio->dev, "registered mdio device %s at address %i\n",
 119                 child->name, addr);
 120
 121         return 0;
 122 }
 123
 124 int of_mdio_parse_addr(struct device *dev, const struct device_node *np)
 125 {
 126         u32 addr;
 127         int ret;
 128
 129         ret = of_property_read_u32(np, "reg", &addr);
 130         if (ret < 0) {
 131                 dev_err(dev, "%s has invalid PHY address\n", np->full_name);
 132                 return ret;
 133         }
 134
 135         /* A PHY must have a reg property in the range [0-31] */
 136         if (addr >= PHY_MAX_ADDR) {
 137                 dev_err(dev, "%s PHY address %i is too large\n",
 138                         np->full_name, addr);
 139                 return -EINVAL;
 140         }
 141
 142         return addr;
 143 }
 144 EXPORT_SYMBOL(of_mdio_parse_addr);
 145
 146 /* The following is a list of PHY compatible strings which appear in
 147  * some DTBs. The compatible string is never matched against a PHY
 148  * driver, so is pointless. We only expect devices which are not PHYs
 149  * to have a compatible string, so they can be matched to an MDIO
 150  * driver.  Encourage users to upgrade their DT blobs to remove these.
 151  */
 152 static const struct of_device_id whitelist_phys[] = {
 153         { .compatible = "brcm,40nm-ephy" },
 154         { .compatible = "marvell,88E1111", },
 155         { .compatible = "marvell,88e1116", },
 156         { .compatible = "marvell,88e1118", },
 157         { .compatible = "marvell,88e1145", },
 158         { .compatible = "marvell,88e1149r", },
 159         { .compatible = "marvell,88e1310", },
 160         { .compatible = "marvell,88E1510", },
 161         { .compatible = "marvell,88E1514", },
 162         { .compatible = "moxa,moxart-rtl8201cp", },
 163         {}
 164 };
 165
 166 /*
 167  * Return true if the child node is for a phy. It must either:
 168  * o Compatible string of "ethernet-phy-idX.X"
 169  * o Compatible string of "ethernet-phy-ieee802.3-c45"
 170  * o Compatible string of "ethernet-phy-ieee802.3-c22"
 171  * o In the white list above (and issue a warning)
 172  * o No compatibility string
 173  *
 174  * A device which is not a phy is expected to have a compatible string
 175  * indicating what sort of device it is.
 176  */
 177 static bool of_mdiobus_child_is_phy(struct device_node *child)
 178 {
 179         u32 phy_id;
 180
 181         if (of_get_phy_id(child, &phy_id) != -EINVAL)
 182                 return true;
 183
 184         if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"))
 185                 return true;
 186
 187         if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22"))
 188                 return true;
 189
 190         if (of_match_node(whitelist_phys, child)) {
 191                 pr_warn(FW_WARN
 192                         "%s: Whitelisted compatible string. Please remove\n",
 193                         child->full_name);
 194                 return true;
 195         }
 196
 197         if (!of_find_property(child, "compatible", NULL))
 198                 return true;
 199
 200         return false;
 201 }
 202
 203 /**
 204  * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
 205  * @mdio: pointer to mii_bus structure
 206  * @np: pointer to device_node of MDIO bus.
 207  *
 208  * This function registers the mii_bus structure and registers a phy_device
 209  * for each child node of @np.
 210  */
 211 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
 212 {
 213         struct device_node *child;
 214         bool scanphys = false;
 215         int addr, rc;
 216
 217         /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
 218          * the device tree are populated after the bus has been registered */
 219         mdio->phy_mask = ~0;
 220
 221         mdio->dev.of_node = np;
 222
 223         /* Register the MDIO bus */
 224         rc = mdiobus_register(mdio);
 225         if (rc)
 226                 return rc;
 227
 228         /* Loop over the child nodes and register a phy_device for each phy */
 229         for_each_available_child_of_node(np, child) {
 230                 addr = of_mdio_parse_addr(&mdio->dev, child);
 231                 if (addr < 0) {
 232                         scanphys = true;
 233                         continue;
 234                 }
 235
 236                 if (of_mdiobus_child_is_phy(child))
 237                         of_mdiobus_register_phy(mdio, child, addr);
 238                 else
 239                         of_mdiobus_register_device(mdio, child, addr);
 240         }
 241
 242         if (!scanphys)
 243                 return 0;
 244
 245         /* auto scan for PHYs with empty reg property */
 246         for_each_available_child_of_node(np, child) {
 247                 /* Skip PHYs with reg property set */
 248                 if (of_find_property(child, "reg", NULL))
 249                         continue;
 250
 251                 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 252                         /* skip already registered PHYs */
 253                         if (mdiobus_is_registered_device(mdio, addr))
 254                                 continue;
 255
 256                         /* be noisy to encourage people to set reg property */
 257                         dev_info(&mdio->dev, "scan phy %s at address %i\n",
 258                                  child->name, addr);
 259
 260                         if (of_mdiobus_child_is_phy(child))
 261                                 of_mdiobus_register_phy(mdio, child, addr);
 262                 }
 263         }
 264
 265         return 0;
 266 }
 267 EXPORT_SYMBOL(of_mdiobus_register);
 268
 269 /* Helper function for of_phy_find_device */
 270 static int of_phy_match(struct device *dev, void *phy_np)
 271 {
 272         return dev->of_node == phy_np;
 273 }
 274
 275 /**
 276  * of_phy_find_device - Give a PHY node, find the phy_device
 277  * @phy_np: Pointer to the phy's device tree node
 278  *
 279  * If successful, returns a pointer to the phy_device with the embedded
 280  * struct device refcount incremented by one, or NULL on failure.
 281  */
 282 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 283 {
 284         struct device *d;
 285         struct mdio_device *mdiodev;
 286
 287         if (!phy_np)
 288                 return NULL;
 289
 290         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 291         if (d) {
 292                 mdiodev = to_mdio_device(d);
 293                 if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY)
 294                         return to_phy_device(d);
 295         }
 296
 297         return NULL;
 298 }
 299 EXPORT_SYMBOL(of_phy_find_device);
 300
 301 /**
 302  * of_phy_connect - Connect to the phy described in the device tree
 303  * @dev: pointer to net_device claiming the phy
 304  * @phy_np: Pointer to device tree node for the PHY
 305  * @hndlr: Link state callback for the network device
 306  * @flags: flags to pass to the PHY
 307  * @iface: PHY data interface type
 308  *
 309  * If successful, returns a pointer to the phy_device with the embedded
 310  * struct device refcount incremented by one, or NULL on failure. The
 311  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 312  */
 313 struct phy_device *of_phy_connect(struct net_device *dev,
 314                                   struct device_node *phy_np,
 315                                   void (*hndlr)(struct net_device *), u32 flags,
 316                                   phy_interface_t iface)
 317 {
 318         struct phy_device *phy = of_phy_find_device(phy_np);
 319         int ret;
 320
 321         if (!phy)
 322                 return NULL;
 323
 324         phy->dev_flags = flags;
 325
 326         ret = phy_connect_direct(dev, phy, hndlr, iface);
 327
 328         /* refcount is held by phy_connect_direct() on success */
 329         put_device(&phy->mdio.dev);
 330
 331         return ret ? NULL : phy;
 332 }
 333 EXPORT_SYMBOL(of_phy_connect);
 334
 335 /**
 336  * of_phy_attach - Attach to a PHY without starting the state machine
 337  * @dev: pointer to net_device claiming the phy
 338  * @phy_np: Node pointer for the PHY
 339  * @flags: flags to pass to the PHY
 340  * @iface: PHY data interface type
 341  *
 342  * If successful, returns a pointer to the phy_device with the embedded
 343  * struct device refcount incremented by one, or NULL on failure. The
 344  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 345  */
 346 struct phy_device *of_phy_attach(struct net_device *dev,
 347                                  struct device_node *phy_np, u32 flags,
 348                                  phy_interface_t iface)
 349 {
 350         struct phy_device *phy = of_phy_find_device(phy_np);
 351         int ret;
 352
 353         if (!phy)
 354                 return NULL;
 355
 356         ret = phy_attach_direct(dev, phy, flags, iface);
 357
 358         /* refcount is held by phy_attach_direct() on success */
 359         put_device(&phy->mdio.dev);
 360
 361         return ret ? NULL : phy;
 362 }
 363 EXPORT_SYMBOL(of_phy_attach);
 364
 365 #if defined(CONFIG_FIXED_PHY)
 366 /*
 367  * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
 368  * support two DT bindings:
 369  * - the old DT binding, where 'fixed-link' was a property with 5
 370  *   cells encoding various informations about the fixed PHY
 371  * - the new DT binding, where 'fixed-link' is a sub-node of the
 372  *   Ethernet device.
 373  */
 374 bool of_phy_is_fixed_link(struct device_node *np)
 375 {
 376         struct device_node *dn;
 377         int len, err;
 378         const char *managed;
 379
 380         /* New binding */
 381         dn = of_get_child_by_name(np, "fixed-link");
 382         if (dn) {
 383                 of_node_put(dn);
 384                 return true;
 385         }
 386
 387         err = of_property_read_string(np, "managed", &managed);
 388         if (err == 0 && strcmp(managed, "auto") != 0)
 389                 return true;
 390
 391         /* Old binding */
 392         if (of_get_property(np, "fixed-link", &len) &&
 393             len == (5 * sizeof(__be32)))
 394                 return true;
 395
 396         return false;
 397 }
 398 EXPORT_SYMBOL(of_phy_is_fixed_link);
 399
 400 int of_phy_register_fixed_link(struct device_node *np)
 401 {
 402         struct fixed_phy_status status = {};
 403         struct device_node *fixed_link_node;
 404         const __be32 *fixed_link_prop;
 405         int link_gpio;
 406         int len, err;
 407         struct phy_device *phy;
 408         const char *managed;
 409
 410         err = of_property_read_string(np, "managed", &managed);
 411         if (err == 0) {
 412                 if (strcmp(managed, "in-band-status") == 0) {
 413                         /* status is zeroed, namely its .link member */
 414                         phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 415                         return PTR_ERR_OR_ZERO(phy);
 416                 }
 417         }
 418
 419         /* New binding */
 420         fixed_link_node = of_get_child_by_name(np, "fixed-link");
 421         if (fixed_link_node) {
 422                 status.link = 1;
 423                 status.duplex = of_property_read_bool(fixed_link_node,
 424                                                       "full-duplex");
 425                 if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
 426                         return -EINVAL;
 427                 status.pause = of_property_read_bool(fixed_link_node, "pause");
 428                 status.asym_pause = of_property_read_bool(fixed_link_node,
 429                                                           "asym-pause");
 430                 link_gpio = of_get_named_gpio_flags(fixed_link_node,
 431                                                     "link-gpios", 0, NULL);
 432                 of_node_put(fixed_link_node);
 433                 if (link_gpio == -EPROBE_DEFER)
 434                         return -EPROBE_DEFER;
 435
 436                 phy = fixed_phy_register(PHY_POLL, &status, link_gpio, np);
 437                 return PTR_ERR_OR_ZERO(phy);
 438         }
 439
 440         /* Old binding */
 441         fixed_link_prop = of_get_property(np, "fixed-link", &len);
 442         if (fixed_link_prop && len == (5 * sizeof(__be32))) {
 443                 status.link = 1;
 444                 status.duplex = be32_to_cpu(fixed_link_prop[1]);
 445                 status.speed = be32_to_cpu(fixed_link_prop[2]);
 446                 status.pause = be32_to_cpu(fixed_link_prop[3]);
 447                 status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
 448                 phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 449                 return PTR_ERR_OR_ZERO(phy);
 450         }
 451
 452         return -ENODEV;
 453 }
 454 EXPORT_SYMBOL(of_phy_register_fixed_link);
 455 #endif