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->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 int of_mdio_parse_addr(struct device *dev, const struct device_node *np)
  96 {
  97         u32 addr;
  98         int ret;
  99
 100         ret = of_property_read_u32(np, "reg", &addr);
 101         if (ret < 0) {
 102                 dev_err(dev, "%s has invalid PHY address\n", np->full_name);
 103                 return ret;
 104         }
 105
 106         /* A PHY must have a reg property in the range [0-31] */
 107         if (addr >= PHY_MAX_ADDR) {
 108                 dev_err(dev, "%s PHY address %i is too large\n",
 109                         np->full_name, addr);
 110                 return -EINVAL;
 111         }
 112
 113         return addr;
 114 }
 115 EXPORT_SYMBOL(of_mdio_parse_addr);
 116
 117 /**
 118  * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
 119  * @mdio: pointer to mii_bus structure
 120  * @np: pointer to device_node of MDIO bus.
 121  *
 122  * This function registers the mii_bus structure and registers a phy_device
 123  * for each child node of @np.
 124  */
 125 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
 126 {
 127         struct device_node *child;
 128         const __be32 *paddr;
 129         bool scanphys = false;
 130         int addr, rc, i;
 131
 132         /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
 133          * the device tree are populated after the bus has been registered */
 134         mdio->phy_mask = ~0;
 135
 136         /* Clear all the IRQ properties */
 137         if (mdio->irq)
 138                 for (i=0; i<PHY_MAX_ADDR; i++)
 139                         mdio->irq[i] = PHY_POLL;
 140
 141         mdio->dev.of_node = np;
 142
 143         /* Register the MDIO bus */
 144         rc = mdiobus_register(mdio);
 145         if (rc)
 146                 return rc;
 147
 148         /* Loop over the child nodes and register a phy_device for each one */
 149         for_each_available_child_of_node(np, child) {
 150                 addr = of_mdio_parse_addr(&mdio->dev, child);
 151                 if (addr < 0) {
 152                         scanphys = true;
 153                         continue;
 154                 }
 155
 156                 rc = of_mdiobus_register_phy(mdio, child, addr);
 157                 if (rc)
 158                         continue;
 159         }
 160
 161         if (!scanphys)
 162                 return 0;
 163
 164         /* auto scan for PHYs with empty reg property */
 165         for_each_available_child_of_node(np, child) {
 166                 /* Skip PHYs with reg property set */
 167                 paddr = of_get_property(child, "reg", NULL);
 168                 if (paddr)
 169                         continue;
 170
 171                 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 172                         /* skip already registered PHYs */
 173                         if (mdio->phy_map[addr])
 174                                 continue;
 175
 176                         /* be noisy to encourage people to set reg property */
 177                         dev_info(&mdio->dev, "scan phy %s at address %i\n",
 178                                  child->name, addr);
 179
 180                         rc = of_mdiobus_register_phy(mdio, child, addr);
 181                         if (rc)
 182                                 continue;
 183                 }
 184         }
 185
 186         return 0;
 187 }
 188 EXPORT_SYMBOL(of_mdiobus_register);
 189
 190 /* Helper function for of_phy_find_device */
 191 static int of_phy_match(struct device *dev, void *phy_np)
 192 {
 193         return dev->of_node == phy_np;
 194 }
 195
 196 /**
 197  * of_phy_find_device - Give a PHY node, find the phy_device
 198  * @phy_np: Pointer to the phy's device tree node
 199  *
 200  * If successful, returns a pointer to the phy_device with the embedded
 201  * struct device refcount incremented by one, or NULL on failure.
 202  */
 203 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 204 {
 205         struct device *d;
 206         if (!phy_np)
 207                 return NULL;
 208
 209         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 210         return d ? to_phy_device(d) : NULL;
 211 }
 212 EXPORT_SYMBOL(of_phy_find_device);
 213
 214 /**
 215  * of_phy_connect - Connect to the phy described in the device tree
 216  * @dev: pointer to net_device claiming the phy
 217  * @phy_np: Pointer to device tree node for the PHY
 218  * @hndlr: Link state callback for the network device
 219  * @iface: PHY data interface type
 220  *
 221  * If successful, returns a pointer to the phy_device with the embedded
 222  * struct device refcount incremented by one, or NULL on failure. The
 223  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 224  */
 225 struct phy_device *of_phy_connect(struct net_device *dev,
 226                                   struct device_node *phy_np,
 227                                   void (*hndlr)(struct net_device *), u32 flags,
 228                                   phy_interface_t iface)
 229 {
 230         struct phy_device *phy = of_phy_find_device(phy_np);
 231         int ret;
 232
 233         if (!phy)
 234                 return NULL;
 235
 236         phy->dev_flags = flags;
 237
 238         ret = phy_connect_direct(dev, phy, hndlr, iface);
 239
 240         /* refcount is held by phy_connect_direct() on success */
 241         put_device(&phy->dev);
 242
 243         return ret ? NULL : phy;
 244 }
 245 EXPORT_SYMBOL(of_phy_connect);
 246
 247 /**
 248  * of_phy_attach - Attach to a PHY without starting the state machine
 249  * @dev: pointer to net_device claiming the phy
 250  * @phy_np: Node pointer for the PHY
 251  * @flags: flags to pass to the PHY
 252  * @iface: PHY data interface type
 253  *
 254  * If successful, returns a pointer to the phy_device with the embedded
 255  * struct device refcount incremented by one, or NULL on failure. The
 256  * refcount must be dropped by calling phy_disconnect() or phy_detach().
 257  */
 258 struct phy_device *of_phy_attach(struct net_device *dev,
 259                                  struct device_node *phy_np, u32 flags,
 260                                  phy_interface_t iface)
 261 {
 262         struct phy_device *phy = of_phy_find_device(phy_np);
 263         int ret;
 264
 265         if (!phy)
 266                 return NULL;
 267
 268         ret = phy_attach_direct(dev, phy, flags, iface);
 269
 270         /* refcount is held by phy_attach_direct() on success */
 271         put_device(&phy->dev);
 272
 273         return ret ? NULL : phy;
 274 }
 275 EXPORT_SYMBOL(of_phy_attach);
 276
 277 #if defined(CONFIG_FIXED_PHY)
 278 /*
 279  * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
 280  * support two DT bindings:
 281  * - the old DT binding, where 'fixed-link' was a property with 5
 282  *   cells encoding various informations about the fixed PHY
 283  * - the new DT binding, where 'fixed-link' is a sub-node of the
 284  *   Ethernet device.
 285  */
 286 bool of_phy_is_fixed_link(struct device_node *np)
 287 {
 288         struct device_node *dn;
 289         int len, err;
 290         const char *managed;
 291
 292         /* New binding */
 293         dn = of_get_child_by_name(np, "fixed-link");
 294         if (dn) {
 295                 of_node_put(dn);
 296                 return true;
 297         }
 298
 299         err = of_property_read_string(np, "managed", &managed);
 300         if (err == 0 && strcmp(managed, "auto") != 0)
 301                 return true;
 302
 303         /* Old binding */
 304         if (of_get_property(np, "fixed-link", &len) &&
 305             len == (5 * sizeof(__be32)))
 306                 return true;
 307
 308         return false;
 309 }
 310 EXPORT_SYMBOL(of_phy_is_fixed_link);
 311
 312 int of_phy_register_fixed_link(struct device_node *np)
 313 {
 314         struct fixed_phy_status status = {};
 315         struct device_node *fixed_link_node;
 316         const __be32 *fixed_link_prop;
 317         int link_gpio;
 318         int len, err;
 319         struct phy_device *phy;
 320         const char *managed;
 321
 322         err = of_property_read_string(np, "managed", &managed);
 323         if (err == 0) {
 324                 if (strcmp(managed, "in-band-status") == 0) {
 325                         /* status is zeroed, namely its .link member */
 326                         phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 327                         return IS_ERR(phy) ? PTR_ERR(phy) : 0;
 328                 }
 329         }
 330
 331         /* New binding */
 332         fixed_link_node = of_get_child_by_name(np, "fixed-link");
 333         if (fixed_link_node) {
 334                 status.link = 1;
 335                 status.duplex = of_property_read_bool(fixed_link_node,
 336                                                       "full-duplex");
 337                 if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
 338                         return -EINVAL;
 339                 status.pause = of_property_read_bool(fixed_link_node, "pause");
 340                 status.asym_pause = of_property_read_bool(fixed_link_node,
 341                                                           "asym-pause");
 342                 link_gpio = of_get_named_gpio_flags(fixed_link_node,
 343                                                     "link-gpios", 0, NULL);
 344                 of_node_put(fixed_link_node);
 345                 if (link_gpio == -EPROBE_DEFER)
 346                         return -EPROBE_DEFER;
 347
 348                 phy = fixed_phy_register(PHY_POLL, &status, link_gpio, np);
 349                 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
 350         }
 351
 352         /* Old binding */
 353         fixed_link_prop = of_get_property(np, "fixed-link", &len);
 354         if (fixed_link_prop && len == (5 * sizeof(__be32))) {
 355                 status.link = 1;
 356                 status.duplex = be32_to_cpu(fixed_link_prop[1]);
 357                 status.speed = be32_to_cpu(fixed_link_prop[2]);
 358                 status.pause = be32_to_cpu(fixed_link_prop[3]);
 359                 status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
 360                 phy = fixed_phy_register(PHY_POLL, &status, -1, np);
 361                 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
 362         }
 363
 364         return -ENODEV;
 365 }
 366 EXPORT_SYMBOL(of_phy_register_fixed_link);
 367 #endif