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 static int of_mdiobus_register_phy(struct mii_bus *mdio, struct device_node *child,
  47                                    u32 addr)
  48 {
  49         struct phy_device *phy;
  50         bool is_c45;
  51         int rc, prev_irq;
  52         u32 max_speed = 0;
  53
  54         is_c45 = of_device_is_compatible(child,
  55                                          "ethernet-phy-ieee802.3-c45");
  56
  57         phy = get_phy_device(mdio, addr, is_c45);
  58         if (!phy || IS_ERR(phy))
  59                 return 1;
  60
  61         if (mdio->irq) {
  62                 prev_irq = mdio->irq[addr];
  63                 mdio->irq[addr] =
  64                         irq_of_parse_and_map(child, 0);
  65                 if (!mdio->irq[addr])
  66                         mdio->irq[addr] = prev_irq;
  67         }
  68
  69         /* Associate the OF node with the device structure so it
  70          * can be looked up later */
  71         of_node_get(child);
  72         phy->dev.of_node = child;
  73
  74         /* All data is now stored in the phy struct;
  75          * register it */
  76         rc = phy_device_register(phy);
  77         if (rc) {
  78                 phy_device_free(phy);
  79                 of_node_put(child);
  80                 return 1;
  81         }
  82
  83         /* Set phydev->supported based on the "max-speed" property
  84          * if present */
  85         if (!of_property_read_u32(child, "max-speed", &max_speed))
  86                 of_set_phy_supported(phy, max_speed);
  87
  88         dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
  89                 child->name, addr);
  90
  91         return 0;
  92 }
  93
  94 /**
  95  * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
  96  * @mdio: pointer to mii_bus structure
  97  * @np: pointer to device_node of MDIO bus.
  98  *
  99  * This function registers the mii_bus structure and registers a phy_device
 100  * for each child node of @np.
 101  */
 102 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
 103 {
 104         struct device_node *child;
 105         const __be32 *paddr;
 106         u32 addr;
 107         bool scanphys = false;
 108         int rc, i, len;
 109
 110         /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
 111          * the device tree are populated after the bus has been registered */
 112         mdio->phy_mask = ~0;
 113
 114         /* Clear all the IRQ properties */
 115         if (mdio->irq)
 116                 for (i=0; i<PHY_MAX_ADDR; i++)
 117                         mdio->irq[i] = PHY_POLL;
 118
 119         mdio->dev.of_node = np;
 120
 121         /* Register the MDIO bus */
 122         rc = mdiobus_register(mdio);
 123         if (rc)
 124                 return rc;
 125
 126         /* Loop over the child nodes and register a phy_device for each one */
 127         for_each_available_child_of_node(np, child) {
 128                 /* A PHY must have a reg property in the range [0-31] */
 129                 paddr = of_get_property(child, "reg", &len);
 130                 if (!paddr || len < sizeof(*paddr)) {
 131                         scanphys = true;
 132                         dev_err(&mdio->dev, "%s has invalid PHY address\n",
 133                                 child->full_name);
 134                         continue;
 135                 }
 136
 137                 addr = be32_to_cpup(paddr);
 138                 if (addr >= PHY_MAX_ADDR) {
 139                         dev_err(&mdio->dev, "%s PHY address %i is too large\n",
 140                                 child->full_name, addr);
 141                         continue;
 142                 }
 143
 144                 rc = of_mdiobus_register_phy(mdio, child, addr);
 145                 if (rc)
 146                         continue;
 147         }
 148
 149         if (!scanphys)
 150                 return 0;
 151
 152         /* auto scan for PHYs with empty reg property */
 153         for_each_available_child_of_node(np, child) {
 154                 /* Skip PHYs with reg property set */
 155                 paddr = of_get_property(child, "reg", &len);
 156                 if (paddr)
 157                         continue;
 158
 159                 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
 160                         /* skip already registered PHYs */
 161                         if (mdio->phy_map[addr])
 162                                 continue;
 163
 164                         /* be noisy to encourage people to set reg property */
 165                         dev_info(&mdio->dev, "scan phy %s at address %i\n",
 166                                  child->name, addr);
 167
 168                         rc = of_mdiobus_register_phy(mdio, child, addr);
 169                         if (rc)
 170                                 continue;
 171                 }
 172         }
 173
 174         return 0;
 175 }
 176 EXPORT_SYMBOL(of_mdiobus_register);
 177
 178 /* Helper function for of_phy_find_device */
 179 static int of_phy_match(struct device *dev, void *phy_np)
 180 {
 181         return dev->of_node == phy_np;
 182 }
 183
 184 /**
 185  * of_phy_find_device - Give a PHY node, find the phy_device
 186  * @phy_np: Pointer to the phy's device tree node
 187  *
 188  * Returns a pointer to the phy_device.
 189  */
 190 struct phy_device *of_phy_find_device(struct device_node *phy_np)
 191 {
 192         struct device *d;
 193         if (!phy_np)
 194                 return NULL;
 195
 196         d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
 197         return d ? to_phy_device(d) : NULL;
 198 }
 199 EXPORT_SYMBOL(of_phy_find_device);
 200
 201 /**
 202  * of_phy_connect - Connect to the phy described in the device tree
 203  * @dev: pointer to net_device claiming the phy
 204  * @phy_np: Pointer to device tree node for the PHY
 205  * @hndlr: Link state callback for the network device
 206  * @iface: PHY data interface type
 207  *
 208  * Returns a pointer to the phy_device if successful.  NULL otherwise
 209  */
 210 struct phy_device *of_phy_connect(struct net_device *dev,
 211                                   struct device_node *phy_np,
 212                                   void (*hndlr)(struct net_device *), u32 flags,
 213                                   phy_interface_t iface)
 214 {
 215         struct phy_device *phy = of_phy_find_device(phy_np);
 216
 217         if (!phy)
 218                 return NULL;
 219
 220         return phy_connect_direct(dev, phy, hndlr, iface) ? NULL : phy;
 221 }
 222 EXPORT_SYMBOL(of_phy_connect);
 223
 224 /**
 225  * of_phy_connect_fixed_link - Parse fixed-link property and return a dummy phy
 226  * @dev: pointer to net_device claiming the phy
 227  * @hndlr: Link state callback for the network device
 228  * @iface: PHY data interface type
 229  *
 230  * This function is a temporary stop-gap and will be removed soon.  It is
 231  * only to support the fs_enet, ucc_geth and gianfar Ethernet drivers.  Do
 232  * not call this function from new drivers.
 233  */
 234 struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
 235                                              void (*hndlr)(struct net_device *),
 236                                              phy_interface_t iface)
 237 {
 238         struct device_node *net_np;
 239         char bus_id[MII_BUS_ID_SIZE + 3];
 240         struct phy_device *phy;
 241         const __be32 *phy_id;
 242         int sz;
 243
 244         if (!dev->dev.parent)
 245                 return NULL;
 246
 247         net_np = dev->dev.parent->of_node;
 248         if (!net_np)
 249                 return NULL;
 250
 251         phy_id = of_get_property(net_np, "fixed-link", &sz);
 252         if (!phy_id || sz < sizeof(*phy_id))
 253                 return NULL;
 254
 255         sprintf(bus_id, PHY_ID_FMT, "fixed-0", be32_to_cpu(phy_id[0]));
 256
 257         phy = phy_connect(dev, bus_id, hndlr, iface);
 258         return IS_ERR(phy) ? NULL : phy;
 259 }
 260 EXPORT_SYMBOL(of_phy_connect_fixed_link);
 261
 262 /**
 263  * of_phy_attach - Attach to a PHY without starting the state machine
 264  * @dev: pointer to net_device claiming the phy
 265  * @phy_np: Node pointer for the PHY
 266  * @flags: flags to pass to the PHY
 267  * @iface: PHY data interface type
 268  */
 269 struct phy_device *of_phy_attach(struct net_device *dev,
 270                                  struct device_node *phy_np, u32 flags,
 271                                  phy_interface_t iface)
 272 {
 273         struct phy_device *phy = of_phy_find_device(phy_np);
 274
 275         if (!phy)
 276                 return NULL;
 277
 278         return phy_attach_direct(dev, phy, flags, iface) ? NULL : phy;
 279 }
 280 EXPORT_SYMBOL(of_phy_attach);