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_irq.h>
  20 #include <linux/of_mdio.h>
  21 #include <linux/module.h>
  22
  23 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
  24 MODULE_LICENSE("GPL");
  25
  26 /* Extract the clause 22 phy ID from the compatible string of the form
  27  * ethernet-phy-idAAAA.BBBB */
  28 static int of_get_phy_id(struct device_node *device, u32 *phy_id)
  29 {
  30         struct property *prop;
  31         const char *cp;
  32         unsigned int upper, lower;
  33
  34         of_property_for_each_string(device, "compatible", prop, cp) {
  35                 if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
  36                         *phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
  37                         return 0;
  38                 }
  39         }
  40         return -EINVAL;
  41 }
  42
  43 static int of_mdiobus_register_phy(struct mii_bus *mdio, struct device_node *child,
  44                                    u32 addr)
  45 {
  46         struct phy_device *phy;
  47         bool is_c45;
  48         int rc;
  49         u32 phy_id;
  50
  51         is_c45 = of_device_is_compatible(child,
  52                                          "ethernet-phy-ieee802.3-c45");
  53
  54         if (!is_c45 && !of_get_phy_id(child, &phy_id))
  55                 phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
  56         else
  57                 phy = get_phy_device(mdio, addr, is_c45);
  58         if (!phy || IS_ERR(phy))
  59                 return 1;
  60
  61         rc = irq_of_parse_and_map(child, 0);
  62         if (rc > 0) {
  63                 phy->irq = rc;
  64                 if (mdio->irq)
  65                         mdio->irq[addr] = rc;
  66         } else {
  67                 if (mdio->irq)
  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->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 1;
  86         }
  87
  88         dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
  89                 child->name, addr);
  90
  91         return 0;
  92 }
  93
  94 int of_mdio_parse_addr(struct device *dev, const struct device_node *np)
  95 {
  96         u32 addr;
  97         int ret;
  98
  99         ret = of_property_read_u32(np, "reg", &addr);
 100         if (ret < 0) {
 101                 dev_err(dev, "%s has invalid PHY address\n", np->full_name);
 102                 return ret;
 103         }
 104
 105         /* A PHY must have a reg property in the range [0-31] */
 106         if (addr >= PHY_MAX_ADDR) {
 107                 dev_err(dev, "%s PHY address %i is too large\n",
 108                         np->full_name, addr);
 109                 return -EINVAL;
 110         }
 111
 112         return addr;
 113 }
 114 EXPORT_SYMBOL(of_mdio_parse_addr);
 115
 116 /**
 117  * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
 118  * @mdio: pointer to mii_bus structure
 119  * @np: pointer to device_node of MDIO bus.
 120  *
 121  * This function registers the mii_bus structure and registers a phy_device
 122  * for each child node of @np.
 123  */
 124 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
 125 {
 126         struct device_node *child;
 127         const __be32 *paddr;
 128         bool scanphys = false;
 129         int addr, rc, i;
 130
 131         /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
 132          * the device tree are populated after the bus has been registered */
 133         mdio->phy_mask = ~0;
 134
 135         /* Clear all the IRQ properties */
 136         if (mdio->irq)
 137                 for (i=0; i<PHY_MAX_ADDR; i++)
 138                         mdio->irq[i] = PHY_POLL;
 139
 140         mdio->dev.of_node = np;
 141
 142         /* Register the MDIO bus */
 143         rc = mdiobus_register(mdio);
 144         if (rc)
 145                 return rc;
 146
 147         /* Loop over the child nodes and register a phy_device for each one */
 148         for_each_available_child_of_node(np, child) {
 149                 addr = of_mdio_parse_addr(&mdio->dev, child);
 150                 if (addr < 0) {
 151                         scanphys = true;
 152                         continue;
 153                 }
 154
 155                 rc = of_mdiobus_register_phy(mdio, child, addr);
 156                 if (rc)
 157                         continue;
 158         }
 159
 160         if (!scanphys)
 161                 return 0;
 162
 163         /* auto scan for PHYs with empty reg property */
 164         for_each_available_child_of_node(np, child) {
 165                 /* Skip PHYs with reg property set */
 166                 paddr = of_get_property(child, "reg", NULL);
 167                 if (paddr)
 168                         continue;
 169
 170                 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 171                         /* skip already registered PHYs */
 172                         if (mdio->phy_map[addr])
 173                                 continue;
 174
 175                         /* be noisy to encourage people to set reg property */
 176                         dev_info(&mdio->dev, "scan phy %s at address %i\n",
 177                                  child->name, addr);
 178
 179                         rc = of_mdiobus_register_phy(mdio, child, addr);
 180                         if (rc)
 181                                 continue;
 182                 }
 183         }
 184
 185         return 0;
 186 }
 187 EXPORT_SYMBOL(of_mdiobus_register);
 188
 189 /* Helper function for of_phy_find_device */
 190 static int of_phy_match(struct device *dev, void *phy_np)
 191 {
 192         return dev->of_node == phy_np;
 193 }
 194
 195 /**
 196  * of_phy_find_device - Give a PHY node, find the phy_device
 197  * @phy_np: Pointer to the phy's device tree node
 198  *
 199  * Returns a pointer to the phy_device.
 200  */
 201 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 202 {
 203         struct device *d;
 204         if (!phy_np)
 205                 return NULL;
 206
 207         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 208         return d ? to_phy_device(d) : NULL;
 209 }
 210 EXPORT_SYMBOL(of_phy_find_device);
 211
 212 /**
 213  * of_phy_connect - Connect to the phy described in the device tree
 214  * @dev: pointer to net_device claiming the phy
 215  * @phy_np: Pointer to device tree node for the PHY
 216  * @hndlr: Link state callback for the network device
 217  * @iface: PHY data interface type
 218  *
 219  * Returns a pointer to the phy_device if successful.  NULL otherwise
 220  */
 221 struct phy_device *of_phy_connect(struct net_device *dev,
 222                                   struct device_node *phy_np,
 223                                   void (*hndlr)(struct net_device *), u32 flags,
 224                                   phy_interface_t iface)
 225 {
 226         struct phy_device *phy = of_phy_find_device(phy_np);
 227
 228         if (!phy)
 229                 return NULL;
 230
 231         phy->dev_flags = flags;
 232
 233         return phy_connect_direct(dev, phy, hndlr, iface) ? NULL : phy;
 234 }
 235 EXPORT_SYMBOL(of_phy_connect);
 236
 237 /**
 238  * of_phy_attach - Attach to a PHY without starting the state machine
 239  * @dev: pointer to net_device claiming the phy
 240  * @phy_np: Node pointer for the PHY
 241  * @flags: flags to pass to the PHY
 242  * @iface: PHY data interface type
 243  */
 244 struct phy_device *of_phy_attach(struct net_device *dev,
 245                                  struct device_node *phy_np, u32 flags,
 246                                  phy_interface_t iface)
 247 {
 248         struct phy_device *phy = of_phy_find_device(phy_np);
 249
 250         if (!phy)
 251                 return NULL;
 252
 253         return phy_attach_direct(dev, phy, flags, iface) ? NULL : phy;
 254 }
 255 EXPORT_SYMBOL(of_phy_attach);
 256
 257 #if defined(CONFIG_FIXED_PHY)
 258 /*
 259  * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
 260  * support two DT bindings:
 261  * - the old DT binding, where 'fixed-link' was a property with 5
 262  *   cells encoding various informations about the fixed PHY
 263  * - the new DT binding, where 'fixed-link' is a sub-node of the
 264  *   Ethernet device.
 265  */
 266 bool of_phy_is_fixed_link(struct device_node *np)
 267 {
 268         struct device_node *dn;
 269         int len;
 270
 271         /* New binding */
 272         dn = of_get_child_by_name(np, "fixed-link");
 273         if (dn) {
 274                 of_node_put(dn);
 275                 return true;
 276         }
 277
 278         /* Old binding */
 279         if (of_get_property(np, "fixed-link", &len) &&
 280             len == (5 * sizeof(__be32)))
 281                 return true;
 282
 283         return false;
 284 }
 285 EXPORT_SYMBOL(of_phy_is_fixed_link);
 286
 287 int of_phy_register_fixed_link(struct device_node *np)
 288 {
 289         struct fixed_phy_status status = {};
 290         struct device_node *fixed_link_node;
 291         const __be32 *fixed_link_prop;
 292         int len;
 293         struct phy_device *phy;
 294
 295         /* New binding */
 296         fixed_link_node = of_get_child_by_name(np, "fixed-link");
 297         if (fixed_link_node) {
 298                 status.link = 1;
 299                 status.duplex = of_property_read_bool(fixed_link_node,
 300                                                       "full-duplex");
 301                 if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
 302                         return -EINVAL;
 303                 status.pause = of_property_read_bool(fixed_link_node, "pause");
 304                 status.asym_pause = of_property_read_bool(fixed_link_node,
 305                                                           "asym-pause");
 306                 of_node_put(fixed_link_node);
 307                 phy = fixed_phy_register(PHY_POLL, &status, np);
 308                 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
 309         }
 310
 311         /* Old binding */
 312         fixed_link_prop = of_get_property(np, "fixed-link", &len);
 313         if (fixed_link_prop && len == (5 * sizeof(__be32))) {
 314                 status.link = 1;
 315                 status.duplex = be32_to_cpu(fixed_link_prop[1]);
 316                 status.speed = be32_to_cpu(fixed_link_prop[2]);
 317                 status.pause = be32_to_cpu(fixed_link_prop[3]);
 318                 status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
 319                 phy = fixed_phy_register(PHY_POLL, &status, np);
 320                 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
 321         }
 322
 323         return -ENODEV;
 324 }
 325 EXPORT_SYMBOL(of_phy_register_fixed_link);
 326 #endif