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