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                 if (mdio->irq)
  66                         mdio->irq[addr] = rc;
  67         } else {
  68                 if (mdio->irq)
  69                         phy->irq = mdio->irq[addr];
  70         }
  71
  72         if (of_property_read_bool(child, "broken-turn-around"))
  73                 mdio->phy_ignore_ta_mask |= 1 << addr;
  74
  75         /* Associate the OF node with the device structure so it
  76          * can be looked up later */
  77         of_node_get(child);
  78         phy->mdio.dev.of_node = child;
  79
  80         /* All data is now stored in the phy struct;
  81          * register it */
  82         rc = phy_device_register(phy);
  83         if (rc) {
  84                 phy_device_free(phy);
  85                 of_node_put(child);
  86                 return 1;
  87         }
  88
  89         dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
  90                 child->name, addr);
  91
  92         return 0;
  93 }
  94
  95 static int of_mdiobus_register_device(struct mii_bus *mdio,
  96                                       struct device_node *child,
  97                                       u32 addr)
  98 {
  99         struct mdio_device *mdiodev;
 100         int rc;
 101
 102         mdiodev = mdio_device_create(mdio, addr);
 103         if (!mdiodev || IS_ERR(mdiodev))
 104                 return 1;
 105
 106         /* Associate the OF node with the device structure so it
 107          * can be looked up later.
 108          */
 109         of_node_get(child);
 110         mdiodev->dev.of_node = child;
 111
 112         /* All data is now stored in the mdiodev struct; register it. */
 113         rc = mdio_device_register(mdiodev);
 114         if (rc) {
 115                 mdio_device_free(mdiodev);
 116                 of_node_put(child);
 117                 return 1;
 118         }
 119
 120         dev_dbg(&mdio->dev, "registered mdio device %s at address %i\n",
 121                 child->name, addr);
 122
 123         return 0;
 124 }
 125
 126 int of_mdio_parse_addr(struct device *dev, const struct device_node *np)
 127 {
 128         u32 addr;
 129         int ret;
 130
 131         ret = of_property_read_u32(np, "reg", &addr);
 132         if (ret < 0) {
 133                 dev_err(dev, "%s has invalid PHY address\n", np->full_name);
 134                 return ret;
 135         }
 136
 137         /* A PHY must have a reg property in the range [0-31] */
 138         if (addr >= PHY_MAX_ADDR) {
 139                 dev_err(dev, "%s PHY address %i is too large\n",
 140                         np->full_name, addr);
 141                 return -EINVAL;
 142         }
 143
 144         return addr;
 145 }
 146 EXPORT_SYMBOL(of_mdio_parse_addr);
 147
 148 /*
 149  * Return true if the child node is for a phy. It must either:
 150  * o Compatible string of "ethernet-phy-idX.X"
 151  * o Compatible string of "ethernet-phy-ieee802.3-c45"
 152  * o Compatible string of "ethernet-phy-ieee802.3-c22"
 153  * o No compatibility string
 154  *
 155  * A device which is not a phy is expected to have a compatible string
 156  * indicating what sort of device it is.
 157  */
 158 static bool of_mdiobus_child_is_phy(struct device_node *child)
 159 {
 160         u32 phy_id;
 161
 162         if (of_get_phy_id(child, &phy_id) != -EINVAL)
 163                 return true;
 164
 165         if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"))
 166                 return true;
 167
 168         if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22"))
 169                 return true;
 170
 171         if (!of_find_property(child, "compatible", NULL))
 172                 return true;
 173
 174         return false;
 175 }
 176
 177 /**
 178  * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
 179  * @mdio: pointer to mii_bus structure
 180  * @np: pointer to device_node of MDIO bus.
 181  *
 182  * This function registers the mii_bus structure and registers a phy_device
 183  * for each child node of @np.
 184  */
 185 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
 186 {
 187         struct device_node *child;
 188         const __be32 *paddr;
 189         bool scanphys = false;
 190         int addr, rc;
 191
 192         /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
 193          * the device tree are populated after the bus has been registered */
 194         mdio->phy_mask = ~0;
 195
 196         mdio->dev.of_node = np;
 197
 198         /* Register the MDIO bus */
 199         rc = mdiobus_register(mdio);
 200         if (rc)
 201                 return rc;
 202
 203         /* Loop over the child nodes and register a phy_device for each phy */
 204         for_each_available_child_of_node(np, child) {
 205                 addr = of_mdio_parse_addr(&mdio->dev, child);
 206                 if (addr < 0) {
 207                         scanphys = true;
 208                         continue;
 209                 }
 210
 211                 if (of_mdiobus_child_is_phy(child))
 212                         of_mdiobus_register_phy(mdio, child, addr);
 213                 else
 214                         of_mdiobus_register_device(mdio, child, addr);
 215         }
 216
 217         if (!scanphys)
 218                 return 0;
 219
 220         /* auto scan for PHYs with empty reg property */
 221         for_each_available_child_of_node(np, child) {
 222                 /* Skip PHYs with reg property set */
 223                 paddr = of_get_property(child, "reg", NULL);
 224                 if (paddr)
 225                         continue;
 226
 227                 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 228                         /* skip already registered PHYs */
 229                         if (mdiobus_is_registered_device(mdio, addr))
 230                                 continue;
 231
 232                         /* be noisy to encourage people to set reg property */
 233                         dev_info(&mdio->dev, "scan phy %s at address %i\n",
 234                                  child->name, addr);
 235
 236                         if (of_mdiobus_child_is_phy(child))
 237                                 of_mdiobus_register_phy(mdio, child, addr);
 238                 }
 239         }
 240
 241         return 0;
 242 }
 243 EXPORT_SYMBOL(of_mdiobus_register);
 244
 245 /* Helper function for of_phy_find_device */
 246 static int of_phy_match(struct device *dev, void *phy_np)
 247 {
 248         return dev->of_node == phy_np;
 249 }
 250
 251 /**
 252  * of_phy_find_device - Give a PHY node, find the phy_device
 253  * @phy_np: Pointer to the phy's device tree node
 254  *
 255  * If successful, returns a pointer to the phy_device with the embedded
 256  * struct device refcount incremented by one, or NULL on failure.
 257  */
 258 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 259 {
 260         struct device *d;
 261         if (!phy_np)
 262                 return NULL;
 263
 264         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 265         return d ? to_phy_device(d) : NULL;
 266 }
 267 EXPORT_SYMBOL(of_phy_find_device);
 268
 269 /**
 270  * of_phy_connect - Connect to the phy described in the device tree
 271  * @dev: pointer to net_device claiming the phy
 272  * @phy_np: Pointer to device tree node for the PHY
 273  * @hndlr: Link state callback for the network device
 274  * @iface: PHY data interface type
 275  *
 276  * If successful, returns a pointer to the phy_device with the embedded
 277  * struct device refcount incremented by one, or NULL on failure. The
 278  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 279  */
 280 struct phy_device *of_phy_connect(struct net_device *dev,
 281                                   struct device_node *phy_np,
 282                                   void (*hndlr)(struct net_device *), u32 flags,
 283                                   phy_interface_t iface)
 284 {
 285         struct phy_device *phy = of_phy_find_device(phy_np);
 286         int ret;
 287
 288         if (!phy)
 289                 return NULL;
 290
 291         phy->dev_flags = flags;
 292
 293         ret = phy_connect_direct(dev, phy, hndlr, iface);
 294
 295         /* refcount is held by phy_connect_direct() on success */
 296         put_device(&phy->mdio.dev);
 297
 298         return ret ? NULL : phy;
 299 }
 300 EXPORT_SYMBOL(of_phy_connect);
 301
 302 /**
 303  * of_phy_attach - Attach to a PHY without starting the state machine
 304  * @dev: pointer to net_device claiming the phy
 305  * @phy_np: Node pointer for the PHY
 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_attach(struct net_device *dev,
 314                                  struct device_node *phy_np, 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         ret = phy_attach_direct(dev, phy, flags, iface);
 324
 325         /* refcount is held by phy_attach_direct() on success */
 326         put_device(&phy->mdio.dev);
 327
 328         return ret ? NULL : phy;
 329 }
 330 EXPORT_SYMBOL(of_phy_attach);
 331
 332 #if defined(CONFIG_FIXED_PHY)
 333 /*
 334  * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
 335  * support two DT bindings:
 336  * - the old DT binding, where 'fixed-link' was a property with 5
 337  *   cells encoding various informations about the fixed PHY
 338  * - the new DT binding, where 'fixed-link' is a sub-node of the
 339  *   Ethernet device.
 340  */
 341 bool of_phy_is_fixed_link(struct device_node *np)
 342 {
 343         struct device_node *dn;
 344         int len, err;
 345         const char *managed;
 346
 347         /* New binding */
 348         dn = of_get_child_by_name(np, "fixed-link");
 349         if (dn) {
 350                 of_node_put(dn);
 351                 return true;
 352         }
 353
 354         err = of_property_read_string(np, "managed", &managed);
 355         if (err == 0 && strcmp(managed, "auto") != 0)
 356                 return true;
 357
 358         /* Old binding */
 359         if (of_get_property(np, "fixed-link", &len) &&
 360             len == (5 * sizeof(__be32)))
 361                 return true;
 362
 363         return false;
 364 }
 365 EXPORT_SYMBOL(of_phy_is_fixed_link);
 366
 367 int of_phy_register_fixed_link(struct device_node *np)
 368 {
 369         struct fixed_phy_status status = {};
 370         struct device_node *fixed_link_node;
 371         const __be32 *fixed_link_prop;
 372         int link_gpio;
 373         int len, err;
 374         struct phy_device *phy;
 375         const char *managed;
 376
 377         err = of_property_read_string(np, "managed", &managed);
 378         if (err == 0) {
 379                 if (strcmp(managed, "in-band-status") == 0) {
 380                         /* status is zeroed, namely its .link member */
 381                         phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 382                         return IS_ERR(phy) ? PTR_ERR(phy) : 0;
 383                 }
 384         }
 385
 386         /* New binding */
 387         fixed_link_node = of_get_child_by_name(np, "fixed-link");
 388         if (fixed_link_node) {
 389                 status.link = 1;
 390                 status.duplex = of_property_read_bool(fixed_link_node,
 391                                                       "full-duplex");
 392                 if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
 393                         return -EINVAL;
 394                 status.pause = of_property_read_bool(fixed_link_node, "pause");
 395                 status.asym_pause = of_property_read_bool(fixed_link_node,
 396                                                           "asym-pause");
 397                 link_gpio = of_get_named_gpio_flags(fixed_link_node,
 398                                                     "link-gpios", 0, NULL);
 399                 of_node_put(fixed_link_node);
 400                 if (link_gpio == -EPROBE_DEFER)
 401                         return -EPROBE_DEFER;
 402
 403                 phy = fixed_phy_register(PHY_POLL, &status, link_gpio, np);
 404                 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
 405         }
 406
 407         /* Old binding */
 408         fixed_link_prop = of_get_property(np, "fixed-link", &len);
 409         if (fixed_link_prop && len == (5 * sizeof(__be32))) {
 410                 status.link = 1;
 411                 status.duplex = be32_to_cpu(fixed_link_prop[1]);
 412                 status.speed = be32_to_cpu(fixed_link_prop[2]);
 413                 status.pause = be32_to_cpu(fixed_link_prop[3]);
 414                 status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
 415                 phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 416                 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
 417         }
 418
 419         return -ENODEV;
 420 }
 421 EXPORT_SYMBOL(of_phy_register_fixed_link);
 422 #endif