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 = "marvell,88E1111", },
 151         { .compatible = "marvell,88e1116", },
 152         { .compatible = "marvell,88e1118", },
 153         { .compatible = "marvell,88e1145", },
 154         { .compatible = "marvell,88e1149r", },
 155         { .compatible = "marvell,88e1310", },
 156         { .compatible = "marvell,88E1510", },
 157         { .compatible = "marvell,88E1514", },
 158         { .compatible = "moxa,moxart-rtl8201cp", },
 159         {}
 160 };
 161
 162 /*
 163  * Return true if the child node is for a phy. It must either:
 164  * o Compatible string of "ethernet-phy-idX.X"
 165  * o Compatible string of "ethernet-phy-ieee802.3-c45"
 166  * o Compatible string of "ethernet-phy-ieee802.3-c22"
 167  * o In the white list above (and issue a warning)
 168  * o No compatibility string
 169  *
 170  * A device which is not a phy is expected to have a compatible string
 171  * indicating what sort of device it is.
 172  */
 173 static bool of_mdiobus_child_is_phy(struct device_node *child)
 174 {
 175         u32 phy_id;
 176
 177         if (of_get_phy_id(child, &phy_id) != -EINVAL)
 178                 return true;
 179
 180         if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"))
 181                 return true;
 182
 183         if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22"))
 184                 return true;
 185
 186         if (of_match_node(whitelist_phys, child)) {
 187                 pr_warn(FW_WARN
 188                         "%s: Whitelisted compatible string. Please remove\n",
 189                         child->full_name);
 190                 return true;
 191         }
 192
 193         if (!of_find_property(child, "compatible", NULL))
 194                 return true;
 195
 196         return false;
 197 }
 198
 199 /**
 200  * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
 201  * @mdio: pointer to mii_bus structure
 202  * @np: pointer to device_node of MDIO bus.
 203  *
 204  * This function registers the mii_bus structure and registers a phy_device
 205  * for each child node of @np.
 206  */
 207 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
 208 {
 209         struct device_node *child;
 210         bool scanphys = false;
 211         int addr, rc;
 212
 213         /* Do not continue if the node is disabled */
 214         if (!of_device_is_available(np))
 215                 return -ENODEV;
 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_get_and_connect
 337  * - Get phy node and connect to the phy described in the device tree
 338  * @dev: pointer to net_device claiming the phy
 339  * @np: Pointer to device tree node for the net_device claiming the phy
 340  * @hndlr: Link state callback for the network device
 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_get_and_connect(struct net_device *dev,
 347                                           struct device_node *np,
 348                                           void (*hndlr)(struct net_device *))
 349 {
 350         phy_interface_t iface;
 351         struct device_node *phy_np;
 352         struct phy_device *phy;
 353
 354         iface = of_get_phy_mode(np);
 355         if (iface < 0)
 356                 return NULL;
 357
 358         phy_np = of_parse_phandle(np, "phy-handle", 0);
 359         if (!phy_np)
 360                 return NULL;
 361
 362         phy = of_phy_connect(dev, phy_np, hndlr, 0, iface);
 363
 364         of_node_put(phy_np);
 365
 366         return phy;
 367 }
 368 EXPORT_SYMBOL(of_phy_get_and_connect);
 369
 370 /**
 371  * of_phy_attach - Attach to a PHY without starting the state machine
 372  * @dev: pointer to net_device claiming the phy
 373  * @phy_np: Node pointer for the PHY
 374  * @flags: flags to pass to the PHY
 375  * @iface: PHY data interface type
 376  *
 377  * If successful, returns a pointer to the phy_device with the embedded
 378  * struct device refcount incremented by one, or NULL on failure. The
 379  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 380  */
 381 struct phy_device *of_phy_attach(struct net_device *dev,
 382                                  struct device_node *phy_np, u32 flags,
 383                                  phy_interface_t iface)
 384 {
 385         struct phy_device *phy = of_phy_find_device(phy_np);
 386         int ret;
 387
 388         if (!phy)
 389                 return NULL;
 390
 391         ret = phy_attach_direct(dev, phy, flags, iface);
 392
 393         /* refcount is held by phy_attach_direct() on success */
 394         put_device(&phy->mdio.dev);
 395
 396         return ret ? NULL : phy;
 397 }
 398 EXPORT_SYMBOL(of_phy_attach);
 399
 400 /*
 401  * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
 402  * support two DT bindings:
 403  * - the old DT binding, where 'fixed-link' was a property with 5
 404  *   cells encoding various informations about the fixed PHY
 405  * - the new DT binding, where 'fixed-link' is a sub-node of the
 406  *   Ethernet device.
 407  */
 408 bool of_phy_is_fixed_link(struct device_node *np)
 409 {
 410         struct device_node *dn;
 411         int len, err;
 412         const char *managed;
 413
 414         /* New binding */
 415         dn = of_get_child_by_name(np, "fixed-link");
 416         if (dn) {
 417                 of_node_put(dn);
 418                 return true;
 419         }
 420
 421         err = of_property_read_string(np, "managed", &managed);
 422         if (err == 0 && strcmp(managed, "auto") != 0)
 423                 return true;
 424
 425         /* Old binding */
 426         if (of_get_property(np, "fixed-link", &len) &&
 427             len == (5 * sizeof(__be32)))
 428                 return true;
 429
 430         return false;
 431 }
 432 EXPORT_SYMBOL(of_phy_is_fixed_link);
 433
 434 int of_phy_register_fixed_link(struct device_node *np)
 435 {
 436         struct fixed_phy_status status = {};
 437         struct device_node *fixed_link_node;
 438         const __be32 *fixed_link_prop;
 439         int link_gpio;
 440         int len, err;
 441         struct phy_device *phy;
 442         const char *managed;
 443
 444         err = of_property_read_string(np, "managed", &managed);
 445         if (err == 0) {
 446                 if (strcmp(managed, "in-band-status") == 0) {
 447                         /* status is zeroed, namely its .link member */
 448                         phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 449                         return PTR_ERR_OR_ZERO(phy);
 450                 }
 451         }
 452
 453         /* New binding */
 454         fixed_link_node = of_get_child_by_name(np, "fixed-link");
 455         if (fixed_link_node) {
 456                 status.link = 1;
 457                 status.duplex = of_property_read_bool(fixed_link_node,
 458                                                       "full-duplex");
 459                 if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
 460                         return -EINVAL;
 461                 status.pause = of_property_read_bool(fixed_link_node, "pause");
 462                 status.asym_pause = of_property_read_bool(fixed_link_node,
 463                                                           "asym-pause");
 464                 link_gpio = of_get_named_gpio_flags(fixed_link_node,
 465                                                     "link-gpios", 0, NULL);
 466                 of_node_put(fixed_link_node);
 467                 if (link_gpio == -EPROBE_DEFER)
 468                         return -EPROBE_DEFER;
 469
 470                 phy = fixed_phy_register(PHY_POLL, &status, link_gpio, np);
 471                 return PTR_ERR_OR_ZERO(phy);
 472         }
 473
 474         /* Old binding */
 475         fixed_link_prop = of_get_property(np, "fixed-link", &len);
 476         if (fixed_link_prop && len == (5 * sizeof(__be32))) {
 477                 status.link = 1;
 478                 status.duplex = be32_to_cpu(fixed_link_prop[1]);
 479                 status.speed = be32_to_cpu(fixed_link_prop[2]);
 480                 status.pause = be32_to_cpu(fixed_link_prop[3]);
 481                 status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
 482                 phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 483                 return PTR_ERR_OR_ZERO(phy);
 484         }
 485
 486         return -ENODEV;
 487 }
 488 EXPORT_SYMBOL(of_phy_register_fixed_link);