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/of.h>
  18 #include <linux/of_irq.h>
  19 #include <linux/of_mdio.h>
  20 #include <linux/module.h>
  21
  22 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
  23 MODULE_LICENSE("GPL");
  24
  25 static void of_set_phy_supported(struct phy_device *phydev, u32 max_speed)
  26 {
  27         /* The default values for phydev->supported are provided by the PHY
  28          * driver "features" member, we want to reset to sane defaults fist
  29          * before supporting higher speeds.
  30          */
  31         phydev->supported &= PHY_DEFAULT_FEATURES;
  32
  33         switch (max_speed) {
  34         default:
  35                 return;
  36
  37         case SPEED_1000:
  38                 phydev->supported |= PHY_1000BT_FEATURES;
  39         case SPEED_100:
  40                 phydev->supported |= PHY_100BT_FEATURES;
  41         case SPEED_10:
  42                 phydev->supported |= PHY_10BT_FEATURES;
  43         }
  44 }
  45
  46 /* Extract the clause 22 phy ID from the compatible string of the form
  47  * ethernet-phy-idAAAA.BBBB */
  48 static int of_get_phy_id(struct device_node *device, u32 *phy_id)
  49 {
  50         struct property *prop;
  51         const char *cp;
  52         unsigned int upper, lower;
  53
  54         of_property_for_each_string(device, "compatible", prop, cp) {
  55                 if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
  56                         *phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
  57                         return 0;
  58                 }
  59         }
  60         return -EINVAL;
  61 }
  62
  63 static int of_mdiobus_register_phy(struct mii_bus *mdio, struct device_node *child,
  64                                    u32 addr)
  65 {
  66         struct phy_device *phy;
  67         bool is_c45;
  68         int rc;
  69         u32 max_speed = 0;
  70         u32 phy_id;
  71
  72         is_c45 = of_device_is_compatible(child,
  73                                          "ethernet-phy-ieee802.3-c45");
  74
  75         if (!is_c45 && !of_get_phy_id(child, &phy_id))
  76                 phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
  77         else
  78                 phy = get_phy_device(mdio, addr, is_c45);
  79         if (!phy || IS_ERR(phy))
  80                 return 1;
  81
  82         rc = irq_of_parse_and_map(child, 0);
  83         if (rc > 0) {
  84                 phy->irq = rc;
  85                 if (mdio->irq)
  86                         mdio->irq[addr] = rc;
  87         } else {
  88                 if (mdio->irq)
  89                         phy->irq = mdio->irq[addr];
  90         }
  91
  92         /* Associate the OF node with the device structure so it
  93          * can be looked up later */
  94         of_node_get(child);
  95         phy->dev.of_node = child;
  96
  97         /* All data is now stored in the phy struct;
  98          * register it */
  99         rc = phy_device_register(phy);
 100         if (rc) {
 101                 phy_device_free(phy);
 102                 of_node_put(child);
 103                 return 1;
 104         }
 105
 106         /* Set phydev->supported based on the "max-speed" property
 107          * if present */
 108         if (!of_property_read_u32(child, "max-speed", &max_speed))
 109                 of_set_phy_supported(phy, max_speed);
 110
 111         dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
 112                 child->name, addr);
 113
 114         return 0;
 115 }
 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         u32 addr;
 130         bool scanphys = false;
 131         int rc, i, len;
 132
 133         /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
 134          * the device tree are populated after the bus has been registered */
 135         mdio->phy_mask = ~0;
 136
 137         /* Clear all the IRQ properties */
 138         if (mdio->irq)
 139                 for (i=0; i<PHY_MAX_ADDR; i++)
 140                         mdio->irq[i] = PHY_POLL;
 141
 142         mdio->dev.of_node = np;
 143
 144         /* Register the MDIO bus */
 145         rc = mdiobus_register(mdio);
 146         if (rc)
 147                 return rc;
 148
 149         /* Loop over the child nodes and register a phy_device for each one */
 150         for_each_available_child_of_node(np, child) {
 151                 /* A PHY must have a reg property in the range [0-31] */
 152                 paddr = of_get_property(child, "reg", &len);
 153                 if (!paddr || len < sizeof(*paddr)) {
 154                         scanphys = true;
 155                         dev_err(&mdio->dev, "%s has invalid PHY address\n",
 156                                 child->full_name);
 157                         continue;
 158                 }
 159
 160                 addr = be32_to_cpup(paddr);
 161                 if (addr >= PHY_MAX_ADDR) {
 162                         dev_err(&mdio->dev, "%s PHY address %i is too large\n",
 163                                 child->full_name, addr);
 164                         continue;
 165                 }
 166
 167                 rc = of_mdiobus_register_phy(mdio, child, addr);
 168                 if (rc)
 169                         continue;
 170         }
 171
 172         if (!scanphys)
 173                 return 0;
 174
 175         /* auto scan for PHYs with empty reg property */
 176         for_each_available_child_of_node(np, child) {
 177                 /* Skip PHYs with reg property set */
 178                 paddr = of_get_property(child, "reg", &len);
 179                 if (paddr)
 180                         continue;
 181
 182                 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 183                         /* skip already registered PHYs */
 184                         if (mdio->phy_map[addr])
 185                                 continue;
 186
 187                         /* be noisy to encourage people to set reg property */
 188                         dev_info(&mdio->dev, "scan phy %s at address %i\n",
 189                                  child->name, addr);
 190
 191                         rc = of_mdiobus_register_phy(mdio, child, addr);
 192                         if (rc)
 193                                 continue;
 194                 }
 195         }
 196
 197         return 0;
 198 }
 199 EXPORT_SYMBOL(of_mdiobus_register);
 200
 201 /* Helper function for of_phy_find_device */
 202 static int of_phy_match(struct device *dev, void *phy_np)
 203 {
 204         return dev->of_node == phy_np;
 205 }
 206
 207 /**
 208  * of_phy_find_device - Give a PHY node, find the phy_device
 209  * @phy_np: Pointer to the phy's device tree node
 210  *
 211  * Returns a pointer to the phy_device.
 212  */
 213 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 214 {
 215         struct device *d;
 216         if (!phy_np)
 217                 return NULL;
 218
 219         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 220         return d ? to_phy_device(d) : NULL;
 221 }
 222 EXPORT_SYMBOL(of_phy_find_device);
 223
 224 /**
 225  * of_phy_connect - Connect to the phy described in the device tree
 226  * @dev: pointer to net_device claiming the phy
 227  * @phy_np: Pointer to device tree node for the PHY
 228  * @hndlr: Link state callback for the network device
 229  * @iface: PHY data interface type
 230  *
 231  * Returns a pointer to the phy_device if successful.  NULL otherwise
 232  */
 233 struct phy_device *of_phy_connect(struct net_device *dev,
 234                                   struct device_node *phy_np,
 235                                   void (*hndlr)(struct net_device *), u32 flags,
 236                                   phy_interface_t iface)
 237 {
 238         struct phy_device *phy = of_phy_find_device(phy_np);
 239
 240         if (!phy)
 241                 return NULL;
 242
 243         return phy_connect_direct(dev, phy, hndlr, iface) ? NULL : phy;
 244 }
 245 EXPORT_SYMBOL(of_phy_connect);
 246
 247 /**
 248  * of_phy_connect_fixed_link - Parse fixed-link property and return a dummy phy
 249  * @dev: pointer to net_device claiming the phy
 250  * @hndlr: Link state callback for the network device
 251  * @iface: PHY data interface type
 252  *
 253  * This function is a temporary stop-gap and will be removed soon.  It is
 254  * only to support the fs_enet, ucc_geth and gianfar Ethernet drivers.  Do
 255  * not call this function from new drivers.
 256  */
 257 struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
 258                                              void (*hndlr)(struct net_device *),
 259                                              phy_interface_t iface)
 260 {
 261         struct device_node *net_np;
 262         char bus_id[MII_BUS_ID_SIZE + 3];
 263         struct phy_device *phy;
 264         const __be32 *phy_id;
 265         int sz;
 266
 267         if (!dev->dev.parent)
 268                 return NULL;
 269
 270         net_np = dev->dev.parent->of_node;
 271         if (!net_np)
 272                 return NULL;
 273
 274         phy_id = of_get_property(net_np, "fixed-link", &sz);
 275         if (!phy_id || sz < sizeof(*phy_id))
 276                 return NULL;
 277
 278         sprintf(bus_id, PHY_ID_FMT, "fixed-0", be32_to_cpu(phy_id[0]));
 279
 280         phy = phy_connect(dev, bus_id, hndlr, iface);
 281         return IS_ERR(phy) ? NULL : phy;
 282 }
 283 EXPORT_SYMBOL(of_phy_connect_fixed_link);
 284
 285 /**
 286  * of_phy_attach - Attach to a PHY without starting the state machine
 287  * @dev: pointer to net_device claiming the phy
 288  * @phy_np: Node pointer for the PHY
 289  * @flags: flags to pass to the PHY
 290  * @iface: PHY data interface type
 291  */
 292 struct phy_device *of_phy_attach(struct net_device *dev,
 293                                  struct device_node *phy_np, u32 flags,
 294                                  phy_interface_t iface)
 295 {
 296         struct phy_device *phy = of_phy_find_device(phy_np);
 297
 298         if (!phy)
 299                 return NULL;
 300
 301         return phy_attach_direct(dev, phy, flags, iface) ? NULL : phy;
 302 }
 303 EXPORT_SYMBOL(of_phy_attach);