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 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
  26 MODULE_LICENSE("GPL");
  27
  28 /* Extract the clause 22 phy ID from the compatible string of the form
  29  * ethernet-phy-idAAAA.BBBB */
  30 static int of_get_phy_id(struct device_node *device, u32 *phy_id)
  31 {
  32         struct property *prop;
  33         const char *cp;
  34         unsigned int upper, lower;
  35
  36         of_property_for_each_string(device, "compatible", prop, cp) {
  37                 if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
  38                         *phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
  39                         return 0;
  40                 }
  41         }
  42         return -EINVAL;
  43 }
  44
  45 static void of_mdiobus_register_phy(struct mii_bus *mdio,
  46                                     struct device_node *child, u32 addr)
  47 {
  48         struct phy_device *phy;
  49         bool is_c45;
  50         int rc;
  51         u32 phy_id;
  52
  53         is_c45 = of_device_is_compatible(child,
  54                                          "ethernet-phy-ieee802.3-c45");
  55
  56         if (!is_c45 && !of_get_phy_id(child, &phy_id))
  57                 phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
  58         else
  59                 phy = get_phy_device(mdio, addr, is_c45);
  60         if (IS_ERR(phy))
  61                 return;
  62
  63         rc = irq_of_parse_and_map(child, 0);
  64         if (rc > 0) {
  65                 phy->irq = rc;
  66                 mdio->irq[addr] = rc;
  67         } else {
  68                 phy->irq = mdio->irq[addr];
  69         }
  70
  71         if (of_property_read_bool(child, "broken-turn-around"))
  72                 mdio->phy_ignore_ta_mask |= 1 << addr;
  73
  74         /* Associate the OF node with the device structure so it
  75          * can be looked up later */
  76         of_node_get(child);
  77         phy->mdio.dev.of_node = child;
  78
  79         /* All data is now stored in the phy struct;
  80          * register it */
  81         rc = phy_device_register(phy);
  82         if (rc) {
  83                 phy_device_free(phy);
  84                 of_node_put(child);
  85                 return;
  86         }
  87
  88         dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
  89                 child->name, addr);
  90 }
  91
  92 static void of_mdiobus_register_device(struct mii_bus *mdio,
  93                                        struct device_node *child, u32 addr)
  94 {
  95         struct mdio_device *mdiodev;
  96         int rc;
  97
  98         mdiodev = mdio_device_create(mdio, addr);
  99         if (IS_ERR(mdiodev))
 100                 return;
 101
 102         /* Associate the OF node with the device structure so it
 103          * can be looked up later.
 104          */
 105         of_node_get(child);
 106         mdiodev->dev.of_node = child;
 107
 108         /* All data is now stored in the mdiodev struct; register it. */
 109         rc = mdio_device_register(mdiodev);
 110         if (rc) {
 111                 mdio_device_free(mdiodev);
 112                 of_node_put(child);
 113                 return;
 114         }
 115
 116         dev_dbg(&mdio->dev, "registered mdio device %s at address %i\n",
 117                 child->name, addr);
 118 }
 119
 120 int of_mdio_parse_addr(struct device *dev, const struct device_node *np)
 121 {
 122         u32 addr;
 123         int ret;
 124
 125         ret = of_property_read_u32(np, "reg", &addr);
 126         if (ret < 0) {
 127                 dev_err(dev, "%s has invalid PHY address\n", np->full_name);
 128                 return ret;
 129         }
 130
 131         /* A PHY must have a reg property in the range [0-31] */
 132         if (addr >= PHY_MAX_ADDR) {
 133                 dev_err(dev, "%s PHY address %i is too large\n",
 134                         np->full_name, addr);
 135                 return -EINVAL;
 136         }
 137
 138         return addr;
 139 }
 140 EXPORT_SYMBOL(of_mdio_parse_addr);
 141
 142 /* The following is a list of PHY compatible strings which appear in
 143  * some DTBs. The compatible string is never matched against a PHY
 144  * driver, so is pointless. We only expect devices which are not PHYs
 145  * to have a compatible string, so they can be matched to an MDIO
 146  * driver.  Encourage users to upgrade their DT blobs to remove these.
 147  */
 148 static const struct of_device_id whitelist_phys[] = {
 149         { .compatible = "brcm,40nm-ephy" },
 150         { .compatible = "broadcom,bcm5241" },
 151         { .compatible = "marvell,88E1111", },
 152         { .compatible = "marvell,88e1116", },
 153         { .compatible = "marvell,88e1118", },
 154         { .compatible = "marvell,88e1145", },
 155         { .compatible = "marvell,88e1149r", },
 156         { .compatible = "marvell,88e1310", },
 157         { .compatible = "marvell,88E1510", },
 158         { .compatible = "marvell,88E1514", },
 159         { .compatible = "moxa,moxart-rtl8201cp", },
 160         {}
 161 };
 162
 163 /*
 164  * Return true if the child node is for a phy. It must either:
 165  * o Compatible string of "ethernet-phy-idX.X"
 166  * o Compatible string of "ethernet-phy-ieee802.3-c45"
 167  * o Compatible string of "ethernet-phy-ieee802.3-c22"
 168  * o In the white list above (and issue a warning)
 169  * o No compatibility string
 170  *
 171  * A device which is not a phy is expected to have a compatible string
 172  * indicating what sort of device it is.
 173  */
 174 static bool of_mdiobus_child_is_phy(struct device_node *child)
 175 {
 176         u32 phy_id;
 177
 178         if (of_get_phy_id(child, &phy_id) != -EINVAL)
 179                 return true;
 180
 181         if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"))
 182                 return true;
 183
 184         if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22"))
 185                 return true;
 186
 187         if (of_match_node(whitelist_phys, child)) {
 188                 pr_warn(FW_WARN
 189                         "%s: Whitelisted compatible string. Please remove\n",
 190                         child->full_name);
 191                 return true;
 192         }
 193
 194         if (!of_find_property(child, "compatible", NULL))
 195                 return true;
 196
 197         return false;
 198 }
 199
 200 /**
 201  * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
 202  * @mdio: pointer to mii_bus structure
 203  * @np: pointer to device_node of MDIO bus.
 204  *
 205  * This function registers the mii_bus structure and registers a phy_device
 206  * for each child node of @np.
 207  */
 208 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
 209 {
 210         struct device_node *child;
 211         bool scanphys = false;
 212         int addr, rc;
 213
 214         /* Do not continue if the node is disabled */
 215         if (!of_device_is_available(np))
 216                 return -ENODEV;
 217
 218         /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
 219          * the device tree are populated after the bus has been registered */
 220         mdio->phy_mask = ~0;
 221
 222         mdio->dev.of_node = np;
 223
 224         /* Register the MDIO bus */
 225         rc = mdiobus_register(mdio);
 226         if (rc)
 227                 return rc;
 228
 229         /* Loop over the child nodes and register a phy_device for each phy */
 230         for_each_available_child_of_node(np, child) {
 231                 addr = of_mdio_parse_addr(&mdio->dev, child);
 232                 if (addr < 0) {
 233                         scanphys = true;
 234                         continue;
 235                 }
 236
 237                 if (of_mdiobus_child_is_phy(child))
 238                         of_mdiobus_register_phy(mdio, child, addr);
 239                 else
 240                         of_mdiobus_register_device(mdio, child, addr);
 241         }
 242
 243         if (!scanphys)
 244                 return 0;
 245
 246         /* auto scan for PHYs with empty reg property */
 247         for_each_available_child_of_node(np, child) {
 248                 /* Skip PHYs with reg property set */
 249                 if (of_find_property(child, "reg", NULL))
 250                         continue;
 251
 252                 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 253                         /* skip already registered PHYs */
 254                         if (mdiobus_is_registered_device(mdio, addr))
 255                                 continue;
 256
 257                         /* be noisy to encourage people to set reg property */
 258                         dev_info(&mdio->dev, "scan phy %s at address %i\n",
 259                                  child->name, addr);
 260
 261                         if (of_mdiobus_child_is_phy(child))
 262                                 of_mdiobus_register_phy(mdio, child, addr);
 263                 }
 264         }
 265
 266         return 0;
 267 }
 268 EXPORT_SYMBOL(of_mdiobus_register);
 269
 270 /* Helper function for of_phy_find_device */
 271 static int of_phy_match(struct device *dev, void *phy_np)
 272 {
 273         return dev->of_node == phy_np;
 274 }
 275
 276 /**
 277  * of_phy_find_device - Give a PHY node, find the phy_device
 278  * @phy_np: Pointer to the phy's device tree node
 279  *
 280  * If successful, returns a pointer to the phy_device with the embedded
 281  * struct device refcount incremented by one, or NULL on failure.
 282  */
 283 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 284 {
 285         struct device *d;
 286         struct mdio_device *mdiodev;
 287
 288         if (!phy_np)
 289                 return NULL;
 290
 291         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 292         if (d) {
 293                 mdiodev = to_mdio_device(d);
 294                 if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY)
 295                         return to_phy_device(d);
 296                 put_device(d);
 297         }
 298
 299         return NULL;
 300 }
 301 EXPORT_SYMBOL(of_phy_find_device);
 302
 303 /**
 304  * of_phy_connect - Connect to the phy described in the device tree
 305  * @dev: pointer to net_device claiming the phy
 306  * @phy_np: Pointer to device tree node for the PHY
 307  * @hndlr: Link state callback for the network device
 308  * @flags: flags to pass to the PHY
 309  * @iface: PHY data interface type
 310  *
 311  * If successful, returns a pointer to the phy_device with the embedded
 312  * struct device refcount incremented by one, or NULL on failure. The
 313  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 314  */
 315 struct phy_device *of_phy_connect(struct net_device *dev,
 316                                   struct device_node *phy_np,
 317                                   void (*hndlr)(struct net_device *), u32 flags,
 318                                   phy_interface_t iface)
 319 {
 320         struct phy_device *phy = of_phy_find_device(phy_np);
 321         int ret;
 322
 323         if (!phy)
 324                 return NULL;
 325
 326         phy->dev_flags = flags;
 327
 328         ret = phy_connect_direct(dev, phy, hndlr, iface);
 329
 330         /* refcount is held by phy_connect_direct() on success */
 331         put_device(&phy->mdio.dev);
 332
 333         return ret ? NULL : phy;
 334 }
 335 EXPORT_SYMBOL(of_phy_connect);
 336
 337 /**
 338  * of_phy_get_and_connect
 339  * - Get phy node and connect to the phy described in the device tree
 340  * @dev: pointer to net_device claiming the phy
 341  * @np: Pointer to device tree node for the net_device claiming the phy
 342  * @hndlr: Link state callback for the network device
 343  *
 344  * If successful, returns a pointer to the phy_device with the embedded
 345  * struct device refcount incremented by one, or NULL on failure. The
 346  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 347  */
 348 struct phy_device *of_phy_get_and_connect(struct net_device *dev,
 349                                           struct device_node *np,
 350                                           void (*hndlr)(struct net_device *))
 351 {
 352         phy_interface_t iface;
 353         struct device_node *phy_np;
 354         struct phy_device *phy;
 355
 356         iface = of_get_phy_mode(np);
 357         if (iface < 0)
 358                 return NULL;
 359
 360         phy_np = of_parse_phandle(np, "phy-handle", 0);
 361         if (!phy_np)
 362                 return NULL;
 363
 364         phy = of_phy_connect(dev, phy_np, hndlr, 0, iface);
 365
 366         of_node_put(phy_np);
 367
 368         return phy;
 369 }
 370 EXPORT_SYMBOL(of_phy_get_and_connect);
 371
 372 /**
 373  * of_phy_attach - Attach to a PHY without starting the state machine
 374  * @dev: pointer to net_device claiming the phy
 375  * @phy_np: Node pointer for the PHY
 376  * @flags: flags to pass to the PHY
 377  * @iface: PHY data interface type
 378  *
 379  * If successful, returns a pointer to the phy_device with the embedded
 380  * struct device refcount incremented by one, or NULL on failure. The
 381  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 382  */
 383 struct phy_device *of_phy_attach(struct net_device *dev,
 384                                  struct device_node *phy_np, u32 flags,
 385                                  phy_interface_t iface)
 386 {
 387         struct phy_device *phy = of_phy_find_device(phy_np);
 388         int ret;
 389
 390         if (!phy)
 391                 return NULL;
 392
 393         ret = phy_attach_direct(dev, phy, flags, iface);
 394
 395         /* refcount is held by phy_attach_direct() on success */
 396         put_device(&phy->mdio.dev);
 397
 398         return ret ? NULL : phy;
 399 }
 400 EXPORT_SYMBOL(of_phy_attach);
 401
 402 /*
 403  * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
 404  * support two DT bindings:
 405  * - the old DT binding, where 'fixed-link' was a property with 5
 406  *   cells encoding various informations about the fixed PHY
 407  * - the new DT binding, where 'fixed-link' is a sub-node of the
 408  *   Ethernet device.
 409  */
 410 bool of_phy_is_fixed_link(struct device_node *np)
 411 {
 412         struct device_node *dn;
 413         int len, err;
 414         const char *managed;
 415
 416         /* New binding */
 417         dn = of_get_child_by_name(np, "fixed-link");
 418         if (dn) {
 419                 of_node_put(dn);
 420                 return true;
 421         }
 422
 423         err = of_property_read_string(np, "managed", &managed);
 424         if (err == 0 && strcmp(managed, "auto") != 0)
 425                 return true;
 426
 427         /* Old binding */
 428         if (of_get_property(np, "fixed-link", &len) &&
 429             len == (5 * sizeof(__be32)))
 430                 return true;
 431
 432         return false;
 433 }
 434 EXPORT_SYMBOL(of_phy_is_fixed_link);
 435
 436 int of_phy_register_fixed_link(struct device_node *np)
 437 {
 438         struct fixed_phy_status status = {};
 439         struct device_node *fixed_link_node;
 440         const __be32 *fixed_link_prop;
 441         int link_gpio;
 442         int len, err;
 443         struct phy_device *phy;
 444         const char *managed;
 445
 446         err = of_property_read_string(np, "managed", &managed);
 447         if (err == 0) {
 448                 if (strcmp(managed, "in-band-status") == 0) {
 449                         /* status is zeroed, namely its .link member */
 450                         phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 451                         return PTR_ERR_OR_ZERO(phy);
 452                 }
 453         }
 454
 455         /* New binding */
 456         fixed_link_node = of_get_child_by_name(np, "fixed-link");
 457         if (fixed_link_node) {
 458                 status.link = 1;
 459                 status.duplex = of_property_read_bool(fixed_link_node,
 460                                                       "full-duplex");
 461                 if (of_property_read_u32(fixed_link_node, "speed",
 462                                          &status.speed)) {
 463                         of_node_put(fixed_link_node);
 464                         return -EINVAL;
 465                 }
 466                 status.pause = of_property_read_bool(fixed_link_node, "pause");
 467                 status.asym_pause = of_property_read_bool(fixed_link_node,
 468                                                           "asym-pause");
 469                 link_gpio = of_get_named_gpio_flags(fixed_link_node,
 470                                                     "link-gpios", 0, NULL);
 471                 of_node_put(fixed_link_node);
 472                 if (link_gpio == -EPROBE_DEFER)
 473                         return -EPROBE_DEFER;
 474
 475                 phy = fixed_phy_register(PHY_POLL, &status, link_gpio, np);
 476                 return PTR_ERR_OR_ZERO(phy);
 477         }
 478
 479         /* Old binding */
 480         fixed_link_prop = of_get_property(np, "fixed-link", &len);
 481         if (fixed_link_prop && len == (5 * sizeof(__be32))) {
 482                 status.link = 1;
 483                 status.duplex = be32_to_cpu(fixed_link_prop[1]);
 484                 status.speed = be32_to_cpu(fixed_link_prop[2]);
 485                 status.pause = be32_to_cpu(fixed_link_prop[3]);
 486                 status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
 487                 phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 488                 return PTR_ERR_OR_ZERO(phy);
 489         }
 490
 491         return -ENODEV;
 492 }
 493 EXPORT_SYMBOL(of_phy_register_fixed_link);
 494
 495 void of_phy_deregister_fixed_link(struct device_node *np)
 496 {
 497         struct phy_device *phydev;
 498
 499         phydev = of_phy_find_device(np);
 500         if (!phydev)
 501                 return;
 502
 503         fixed_phy_unregister(phydev);
 504
 505         put_device(&phydev->mdio.dev);  /* of_phy_find_device() */
 506         phy_device_free(phydev);        /* fixed_phy_register() */
 507 }
 508 EXPORT_SYMBOL(of_phy_deregister_fixed_link);