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 (!phy || IS_ERR(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 (!mdiodev || 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         const __be32 *paddr;
 215         bool scanphys = false;
 216         int addr, rc;
 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                 paddr = of_get_property(child, "reg", NULL);
 250                 if (paddr)
 251                         continue;
 252
 253                 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 254                         /* skip already registered PHYs */
 255                         if (mdiobus_is_registered_device(mdio, addr))
 256                                 continue;
 257
 258                         /* be noisy to encourage people to set reg property */
 259                         dev_info(&mdio->dev, "scan phy %s at address %i\n",
 260                                  child->name, addr);
 261
 262                         if (of_mdiobus_child_is_phy(child))
 263                                 of_mdiobus_register_phy(mdio, child, addr);
 264                 }
 265         }
 266
 267         return 0;
 268 }
 269 EXPORT_SYMBOL(of_mdiobus_register);
 270
 271 /* Helper function for of_phy_find_device */
 272 static int of_phy_match(struct device *dev, void *phy_np)
 273 {
 274         return dev->of_node == phy_np;
 275 }
 276
 277 /**
 278  * of_phy_find_device - Give a PHY node, find the phy_device
 279  * @phy_np: Pointer to the phy's device tree node
 280  *
 281  * If successful, returns a pointer to the phy_device with the embedded
 282  * struct device refcount incremented by one, or NULL on failure.
 283  */
 284 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 285 {
 286         struct device *d;
 287         struct mdio_device *mdiodev;
 288
 289         if (!phy_np)
 290                 return NULL;
 291
 292         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 293         if (d) {
 294                 mdiodev = to_mdio_device(d);
 295                 if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY)
 296                         return to_phy_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  * @iface: PHY data interface type
 309  *
 310  * If successful, returns a pointer to the phy_device with the embedded
 311  * struct device refcount incremented by one, or NULL on failure. The
 312  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 313  */
 314 struct phy_device *of_phy_connect(struct net_device *dev,
 315                                   struct device_node *phy_np,
 316                                   void (*hndlr)(struct net_device *), u32 flags,
 317                                   phy_interface_t iface)
 318 {
 319         struct phy_device *phy = of_phy_find_device(phy_np);
 320         int ret;
 321
 322         if (!phy)
 323                 return NULL;
 324
 325         phy->dev_flags = flags;
 326
 327         ret = phy_connect_direct(dev, phy, hndlr, iface);
 328
 329         /* refcount is held by phy_connect_direct() on success */
 330         put_device(&phy->mdio.dev);
 331
 332         return ret ? NULL : phy;
 333 }
 334 EXPORT_SYMBOL(of_phy_connect);
 335
 336 /**
 337  * of_phy_attach - Attach to a PHY without starting the state machine
 338  * @dev: pointer to net_device claiming the phy
 339  * @phy_np: Node pointer for the PHY
 340  * @flags: flags to pass to the PHY
 341  * @iface: PHY data interface type
 342  *
 343  * If successful, returns a pointer to the phy_device with the embedded
 344  * struct device refcount incremented by one, or NULL on failure. The
 345  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 346  */
 347 struct phy_device *of_phy_attach(struct net_device *dev,
 348                                  struct device_node *phy_np, u32 flags,
 349                                  phy_interface_t iface)
 350 {
 351         struct phy_device *phy = of_phy_find_device(phy_np);
 352         int ret;
 353
 354         if (!phy)
 355                 return NULL;
 356
 357         ret = phy_attach_direct(dev, phy, flags, iface);
 358
 359         /* refcount is held by phy_attach_direct() on success */
 360         put_device(&phy->mdio.dev);
 361
 362         return ret ? NULL : phy;
 363 }
 364 EXPORT_SYMBOL(of_phy_attach);
 365
 366 #if defined(CONFIG_FIXED_PHY)
 367 /*
 368  * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
 369  * support two DT bindings:
 370  * - the old DT binding, where 'fixed-link' was a property with 5
 371  *   cells encoding various informations about the fixed PHY
 372  * - the new DT binding, where 'fixed-link' is a sub-node of the
 373  *   Ethernet device.
 374  */
 375 bool of_phy_is_fixed_link(struct device_node *np)
 376 {
 377         struct device_node *dn;
 378         int len, err;
 379         const char *managed;
 380
 381         /* New binding */
 382         dn = of_get_child_by_name(np, "fixed-link");
 383         if (dn) {
 384                 of_node_put(dn);
 385                 return true;
 386         }
 387
 388         err = of_property_read_string(np, "managed", &managed);
 389         if (err == 0 && strcmp(managed, "auto") != 0)
 390                 return true;
 391
 392         /* Old binding */
 393         if (of_get_property(np, "fixed-link", &len) &&
 394             len == (5 * sizeof(__be32)))
 395                 return true;
 396
 397         return false;
 398 }
 399 EXPORT_SYMBOL(of_phy_is_fixed_link);
 400
 401 int of_phy_register_fixed_link(struct device_node *np)
 402 {
 403         struct fixed_phy_status status = {};
 404         struct device_node *fixed_link_node;
 405         const __be32 *fixed_link_prop;
 406         int link_gpio;
 407         int len, err;
 408         struct phy_device *phy;
 409         const char *managed;
 410
 411         err = of_property_read_string(np, "managed", &managed);
 412         if (err == 0) {
 413                 if (strcmp(managed, "in-band-status") == 0) {
 414                         /* status is zeroed, namely its .link member */
 415                         phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 416                         return IS_ERR(phy) ? PTR_ERR(phy) : 0;
 417                 }
 418         }
 419
 420         /* New binding */
 421         fixed_link_node = of_get_child_by_name(np, "fixed-link");
 422         if (fixed_link_node) {
 423                 status.link = 1;
 424                 status.duplex = of_property_read_bool(fixed_link_node,
 425                                                       "full-duplex");
 426                 if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
 427                         return -EINVAL;
 428                 status.pause = of_property_read_bool(fixed_link_node, "pause");
 429                 status.asym_pause = of_property_read_bool(fixed_link_node,
 430                                                           "asym-pause");
 431                 link_gpio = of_get_named_gpio_flags(fixed_link_node,
 432                                                     "link-gpios", 0, NULL);
 433                 of_node_put(fixed_link_node);
 434                 if (link_gpio == -EPROBE_DEFER)
 435                         return -EPROBE_DEFER;
 436
 437                 phy = fixed_phy_register(PHY_POLL, &status, link_gpio, np);
 438                 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
 439         }
 440
 441         /* Old binding */
 442         fixed_link_prop = of_get_property(np, "fixed-link", &len);
 443         if (fixed_link_prop && len == (5 * sizeof(__be32))) {
 444                 status.link = 1;
 445                 status.duplex = be32_to_cpu(fixed_link_prop[1]);
 446                 status.speed = be32_to_cpu(fixed_link_prop[2]);
 447                 status.pause = be32_to_cpu(fixed_link_prop[3]);
 448                 status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
 449                 phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 450                 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
 451         }
 452
 453         return -ENODEV;
 454 }
 455 EXPORT_SYMBOL(of_phy_register_fixed_link);
 456 #endif