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/of_net.h>
  23 #include <linux/module.h>
  24
  25 #define DEFAULT_GPIO_RESET_DELAY        10      /* in microseconds */
  26
  27 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
  28 MODULE_LICENSE("GPL");
  29
  30 /* Extract the clause 22 phy ID from the compatible string of the form
  31  * ethernet-phy-idAAAA.BBBB */
  32 static int of_get_phy_id(struct device_node *device, u32 *phy_id)
  33 {
  34         struct property *prop;
  35         const char *cp;
  36         unsigned int upper, lower;
  37
  38         of_property_for_each_string(device, "compatible", prop, cp) {
  39                 if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
  40                         *phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
  41                         return 0;
  42                 }
  43         }
  44         return -EINVAL;
  45 }
  46
  47 static void of_mdiobus_register_phy(struct mii_bus *mdio,
  48                                     struct device_node *child, u32 addr)
  49 {
  50         struct phy_device *phy;
  51         bool is_c45;
  52         int rc;
  53         u32 phy_id;
  54
  55         is_c45 = of_device_is_compatible(child,
  56                                          "ethernet-phy-ieee802.3-c45");
  57
  58         if (!is_c45 && !of_get_phy_id(child, &phy_id))
  59                 phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
  60         else
  61                 phy = get_phy_device(mdio, addr, is_c45);
  62         if (IS_ERR(phy))
  63                 return;
  64
  65         rc = irq_of_parse_and_map(child, 0);
  66         if (rc > 0) {
  67                 phy->irq = rc;
  68                 mdio->irq[addr] = rc;
  69         } else {
  70                 phy->irq = mdio->irq[addr];
  71         }
  72
  73         if (of_property_read_bool(child, "broken-turn-around"))
  74                 mdio->phy_ignore_ta_mask |= 1 << addr;
  75
  76         /* Associate the OF node with the device structure so it
  77          * can be looked up later */
  78         of_node_get(child);
  79         phy->mdio.dev.of_node = child;
  80
  81         /* All data is now stored in the phy struct;
  82          * register it */
  83         rc = phy_device_register(phy);
  84         if (rc) {
  85                 phy_device_free(phy);
  86                 of_node_put(child);
  87                 return;
  88         }
  89
  90         dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
  91                 child->name, addr);
  92 }
  93
  94 static void of_mdiobus_register_device(struct mii_bus *mdio,
  95                                        struct device_node *child, 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;
 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;
 116         }
 117
 118         dev_dbg(&mdio->dev, "registered mdio device %s at address %i\n",
 119                 child->name, addr);
 120 }
 121
 122 int of_mdio_parse_addr(struct device *dev, const struct device_node *np)
 123 {
 124         u32 addr;
 125         int ret;
 126
 127         ret = of_property_read_u32(np, "reg", &addr);
 128         if (ret < 0) {
 129                 dev_err(dev, "%s has invalid PHY address\n", np->full_name);
 130                 return ret;
 131         }
 132
 133         /* A PHY must have a reg property in the range [0-31] */
 134         if (addr >= PHY_MAX_ADDR) {
 135                 dev_err(dev, "%s PHY address %i is too large\n",
 136                         np->full_name, addr);
 137                 return -EINVAL;
 138         }
 139
 140         return addr;
 141 }
 142 EXPORT_SYMBOL(of_mdio_parse_addr);
 143
 144 /* The following is a list of PHY compatible strings which appear in
 145  * some DTBs. The compatible string is never matched against a PHY
 146  * driver, so is pointless. We only expect devices which are not PHYs
 147  * to have a compatible string, so they can be matched to an MDIO
 148  * driver.  Encourage users to upgrade their DT blobs to remove these.
 149  */
 150 static const struct of_device_id whitelist_phys[] = {
 151         { .compatible = "brcm,40nm-ephy" },
 152         { .compatible = "broadcom,bcm5241" },
 153         { .compatible = "marvell,88E1111", },
 154         { .compatible = "marvell,88e1116", },
 155         { .compatible = "marvell,88e1118", },
 156         { .compatible = "marvell,88e1145", },
 157         { .compatible = "marvell,88e1149r", },
 158         { .compatible = "marvell,88e1310", },
 159         { .compatible = "marvell,88E1510", },
 160         { .compatible = "marvell,88E1514", },
 161         { .compatible = "moxa,moxart-rtl8201cp", },
 162         {}
 163 };
 164
 165 /*
 166  * Return true if the child node is for a phy. It must either:
 167  * o Compatible string of "ethernet-phy-idX.X"
 168  * o Compatible string of "ethernet-phy-ieee802.3-c45"
 169  * o Compatible string of "ethernet-phy-ieee802.3-c22"
 170  * o In the white list above (and issue a warning)
 171  * o No compatibility string
 172  *
 173  * A device which is not a phy is expected to have a compatible string
 174  * indicating what sort of device it is.
 175  */
 176 static bool of_mdiobus_child_is_phy(struct device_node *child)
 177 {
 178         u32 phy_id;
 179
 180         if (of_get_phy_id(child, &phy_id) != -EINVAL)
 181                 return true;
 182
 183         if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"))
 184                 return true;
 185
 186         if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22"))
 187                 return true;
 188
 189         if (of_match_node(whitelist_phys, child)) {
 190                 pr_warn(FW_WARN
 191                         "%s: Whitelisted compatible string. Please remove\n",
 192                         child->full_name);
 193                 return true;
 194         }
 195
 196         if (!of_find_property(child, "compatible", NULL))
 197                 return true;
 198
 199         return false;
 200 }
 201
 202 /**
 203  * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
 204  * @mdio: pointer to mii_bus structure
 205  * @np: pointer to device_node of MDIO bus.
 206  *
 207  * This function registers the mii_bus structure and registers a phy_device
 208  * for each child node of @np.
 209  */
 210 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
 211 {
 212         struct device_node *child;
 213         bool scanphys = false;
 214         int addr, rc;
 215
 216         /* Do not continue if the node is disabled */
 217         if (!of_device_is_available(np))
 218                 return -ENODEV;
 219
 220         /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
 221          * the device tree are populated after the bus has been registered */
 222         mdio->phy_mask = ~0;
 223
 224         mdio->dev.of_node = np;
 225
 226         /* Get bus level PHY reset GPIO details */
 227         mdio->reset_delay_us = DEFAULT_GPIO_RESET_DELAY;
 228         of_property_read_u32(np, "reset-delay-us", &mdio->reset_delay_us);
 229         mdio->num_reset_gpios = of_gpio_named_count(np, "reset-gpios");
 230
 231         /* Register the MDIO bus */
 232         rc = mdiobus_register(mdio);
 233         if (rc)
 234                 return rc;
 235
 236         /* Loop over the child nodes and register a phy_device for each phy */
 237         for_each_available_child_of_node(np, child) {
 238                 addr = of_mdio_parse_addr(&mdio->dev, child);
 239                 if (addr < 0) {
 240                         scanphys = true;
 241                         continue;
 242                 }
 243
 244                 if (of_mdiobus_child_is_phy(child))
 245                         of_mdiobus_register_phy(mdio, child, addr);
 246                 else
 247                         of_mdiobus_register_device(mdio, child, addr);
 248         }
 249
 250         if (!scanphys)
 251                 return 0;
 252
 253         /* auto scan for PHYs with empty reg property */
 254         for_each_available_child_of_node(np, child) {
 255                 /* Skip PHYs with reg property set */
 256                 if (of_find_property(child, "reg", NULL))
 257                         continue;
 258
 259                 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 260                         /* skip already registered PHYs */
 261                         if (mdiobus_is_registered_device(mdio, addr))
 262                                 continue;
 263
 264                         /* be noisy to encourage people to set reg property */
 265                         dev_info(&mdio->dev, "scan phy %s at address %i\n",
 266                                  child->name, addr);
 267
 268                         if (of_mdiobus_child_is_phy(child))
 269                                 of_mdiobus_register_phy(mdio, child, addr);
 270                 }
 271         }
 272
 273         return 0;
 274 }
 275 EXPORT_SYMBOL(of_mdiobus_register);
 276
 277 /* Helper function for of_phy_find_device */
 278 static int of_phy_match(struct device *dev, void *phy_np)
 279 {
 280         return dev->of_node == phy_np;
 281 }
 282
 283 /**
 284  * of_phy_find_device - Give a PHY node, find the phy_device
 285  * @phy_np: Pointer to the phy's device tree node
 286  *
 287  * If successful, returns a pointer to the phy_device with the embedded
 288  * struct device refcount incremented by one, or NULL on failure.
 289  */
 290 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 291 {
 292         struct device *d;
 293         struct mdio_device *mdiodev;
 294
 295         if (!phy_np)
 296                 return NULL;
 297
 298         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 299         if (d) {
 300                 mdiodev = to_mdio_device(d);
 301                 if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY)
 302                         return to_phy_device(d);
 303                 put_device(d);
 304         }
 305
 306         return NULL;
 307 }
 308 EXPORT_SYMBOL(of_phy_find_device);
 309
 310 /**
 311  * of_phy_connect - Connect to the phy described in the device tree
 312  * @dev: pointer to net_device claiming the phy
 313  * @phy_np: Pointer to device tree node for the PHY
 314  * @hndlr: Link state callback for the network device
 315  * @flags: flags to pass to the PHY
 316  * @iface: PHY data interface type
 317  *
 318  * If successful, returns a pointer to the phy_device with the embedded
 319  * struct device refcount incremented by one, or NULL on failure. The
 320  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 321  */
 322 struct phy_device *of_phy_connect(struct net_device *dev,
 323                                   struct device_node *phy_np,
 324                                   void (*hndlr)(struct net_device *), u32 flags,
 325                                   phy_interface_t iface)
 326 {
 327         struct phy_device *phy = of_phy_find_device(phy_np);
 328         int ret;
 329
 330         if (!phy)
 331                 return NULL;
 332
 333         phy->dev_flags = flags;
 334
 335         ret = phy_connect_direct(dev, phy, hndlr, iface);
 336
 337         /* refcount is held by phy_connect_direct() on success */
 338         put_device(&phy->mdio.dev);
 339
 340         return ret ? NULL : phy;
 341 }
 342 EXPORT_SYMBOL(of_phy_connect);
 343
 344 /**
 345  * of_phy_get_and_connect
 346  * - Get phy node and connect to the phy described in the device tree
 347  * @dev: pointer to net_device claiming the phy
 348  * @np: Pointer to device tree node for the net_device claiming the phy
 349  * @hndlr: Link state callback for the network device
 350  *
 351  * If successful, returns a pointer to the phy_device with the embedded
 352  * struct device refcount incremented by one, or NULL on failure. The
 353  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 354  */
 355 struct phy_device *of_phy_get_and_connect(struct net_device *dev,
 356                                           struct device_node *np,
 357                                           void (*hndlr)(struct net_device *))
 358 {
 359         phy_interface_t iface;
 360         struct device_node *phy_np;
 361         struct phy_device *phy;
 362
 363         iface = of_get_phy_mode(np);
 364         if (iface < 0)
 365                 return NULL;
 366
 367         phy_np = of_parse_phandle(np, "phy-handle", 0);
 368         if (!phy_np)
 369                 return NULL;
 370
 371         phy = of_phy_connect(dev, phy_np, hndlr, 0, iface);
 372
 373         of_node_put(phy_np);
 374
 375         return phy;
 376 }
 377 EXPORT_SYMBOL(of_phy_get_and_connect);
 378
 379 /**
 380  * of_phy_attach - Attach to a PHY without starting the state machine
 381  * @dev: pointer to net_device claiming the phy
 382  * @phy_np: Node pointer for the PHY
 383  * @flags: flags to pass to the PHY
 384  * @iface: PHY data interface type
 385  *
 386  * If successful, returns a pointer to the phy_device with the embedded
 387  * struct device refcount incremented by one, or NULL on failure. The
 388  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 389  */
 390 struct phy_device *of_phy_attach(struct net_device *dev,
 391                                  struct device_node *phy_np, u32 flags,
 392                                  phy_interface_t iface)
 393 {
 394         struct phy_device *phy = of_phy_find_device(phy_np);
 395         int ret;
 396
 397         if (!phy)
 398                 return NULL;
 399
 400         ret = phy_attach_direct(dev, phy, flags, iface);
 401
 402         /* refcount is held by phy_attach_direct() on success */
 403         put_device(&phy->mdio.dev);
 404
 405         return ret ? NULL : phy;
 406 }
 407 EXPORT_SYMBOL(of_phy_attach);
 408
 409 /*
 410  * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
 411  * support two DT bindings:
 412  * - the old DT binding, where 'fixed-link' was a property with 5
 413  *   cells encoding various informations about the fixed PHY
 414  * - the new DT binding, where 'fixed-link' is a sub-node of the
 415  *   Ethernet device.
 416  */
 417 bool of_phy_is_fixed_link(struct device_node *np)
 418 {
 419         struct device_node *dn;
 420         int len, err;
 421         const char *managed;
 422
 423         /* New binding */
 424         dn = of_get_child_by_name(np, "fixed-link");
 425         if (dn) {
 426                 of_node_put(dn);
 427                 return true;
 428         }
 429
 430         err = of_property_read_string(np, "managed", &managed);
 431         if (err == 0 && strcmp(managed, "auto") != 0)
 432                 return true;
 433
 434         /* Old binding */
 435         if (of_get_property(np, "fixed-link", &len) &&
 436             len == (5 * sizeof(__be32)))
 437                 return true;
 438
 439         return false;
 440 }
 441 EXPORT_SYMBOL(of_phy_is_fixed_link);
 442
 443 int of_phy_register_fixed_link(struct device_node *np)
 444 {
 445         struct fixed_phy_status status = {};
 446         struct device_node *fixed_link_node;
 447         const __be32 *fixed_link_prop;
 448         int link_gpio;
 449         int len, err;
 450         struct phy_device *phy;
 451         const char *managed;
 452
 453         err = of_property_read_string(np, "managed", &managed);
 454         if (err == 0) {
 455                 if (strcmp(managed, "in-band-status") == 0) {
 456                         /* status is zeroed, namely its .link member */
 457                         phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 458                         return PTR_ERR_OR_ZERO(phy);
 459                 }
 460         }
 461
 462         /* New binding */
 463         fixed_link_node = of_get_child_by_name(np, "fixed-link");
 464         if (fixed_link_node) {
 465                 status.link = 1;
 466                 status.duplex = of_property_read_bool(fixed_link_node,
 467                                                       "full-duplex");
 468                 if (of_property_read_u32(fixed_link_node, "speed",
 469                                          &status.speed)) {
 470                         of_node_put(fixed_link_node);
 471                         return -EINVAL;
 472                 }
 473                 status.pause = of_property_read_bool(fixed_link_node, "pause");
 474                 status.asym_pause = of_property_read_bool(fixed_link_node,
 475                                                           "asym-pause");
 476                 link_gpio = of_get_named_gpio_flags(fixed_link_node,
 477                                                     "link-gpios", 0, NULL);
 478                 of_node_put(fixed_link_node);
 479                 if (link_gpio == -EPROBE_DEFER)
 480                         return -EPROBE_DEFER;
 481
 482                 phy = fixed_phy_register(PHY_POLL, &status, link_gpio, np);
 483                 return PTR_ERR_OR_ZERO(phy);
 484         }
 485
 486         /* Old binding */
 487         fixed_link_prop = of_get_property(np, "fixed-link", &len);
 488         if (fixed_link_prop && len == (5 * sizeof(__be32))) {
 489                 status.link = 1;
 490                 status.duplex = be32_to_cpu(fixed_link_prop[1]);
 491                 status.speed = be32_to_cpu(fixed_link_prop[2]);
 492                 status.pause = be32_to_cpu(fixed_link_prop[3]);
 493                 status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
 494                 phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 495                 return PTR_ERR_OR_ZERO(phy);
 496         }
 497
 498         return -ENODEV;
 499 }
 500 EXPORT_SYMBOL(of_phy_register_fixed_link);
 501
 502 void of_phy_deregister_fixed_link(struct device_node *np)
 503 {
 504         struct phy_device *phydev;
 505
 506         phydev = of_phy_find_device(np);
 507         if (!phydev)
 508                 return;
 509
 510         fixed_phy_unregister(phydev);
 511
 512         put_device(&phydev->mdio.dev);  /* of_phy_find_device() */
 513         phy_device_free(phydev);        /* fixed_phy_register() */
 514 }
 515 EXPORT_SYMBOL(of_phy_deregister_fixed_link);