of_mdio.c

Go to the documentation of this file.

/*
 * OF helpers for the MDIO (Ethernet PHY) API
 *
 * Copyright (c) 2009 Secret Lab Technologies, Ltd.
 *
 * This file is released under the GPLv2
 *
 * This file provides helper functions for extracting PHY device information
 * out of the OpenFirmware device tree and using it to populate an mii_bus.
 */

#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/netdevice.h>
#include <linux/err.h>
#include <linux/phy.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_mdio.h>
#include <linux/module.h>

MODULE_AUTHOR("Grant Likely <[email protected]>");
MODULE_LICENSE("GPL");

int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
{
    struct phy_device *phy;
    struct device_node *child;
    int rc, i;

    /* Mask out all PHYs from auto probing.  Instead the PHYs listed in
     * the device tree are populated after the bus has been registered */
    mdio->phy_mask = ~0;

    /* Clear all the IRQ properties */
    if (mdio->irq)
        for (i=0; i<PHY_MAX_ADDR; i++)
            mdio->irq[i] = PHY_POLL;

    mdio->dev.of_node = np;

    /* Register the MDIO bus */
    rc = mdiobus_register(mdio);
    if (rc)
        return rc;

    /* Loop over the child nodes and register a phy_device for each one */
    for_each_child_of_node(np, child) {
        const __be32 *paddr;
        u32 addr;
        int len;
        bool is_c45;

        /* A PHY must have a reg property in the range [0-31] */
        paddr = of_get_property(child, "reg", &len);
        if (!paddr || len < sizeof(*paddr)) {
            dev_err(&mdio->dev, "%s has invalid PHY address\n",
                child->full_name);
            continue;
        }

        addr = be32_to_cpup(paddr);
        if (addr >= 32) {
            dev_err(&mdio->dev, "%s PHY address %i is too large\n",
                child->full_name, addr);
            continue;
        }

        if (mdio->irq) {
            mdio->irq[addr] = irq_of_parse_and_map(child, 0);
            if (!mdio->irq[addr])
                mdio->irq[addr] = PHY_POLL;
        }

        is_c45 = of_device_is_compatible(child,
                         "ethernet-phy-ieee802.3-c45");
        phy = get_phy_device(mdio, addr, is_c45);

        if (!phy || IS_ERR(phy)) {
            phy = phy_device_create(mdio, addr, 0, false, NULL);
            if (!phy || IS_ERR(phy)) {
                dev_err(&mdio->dev,
                    "error creating PHY at address %i\n",
                    addr);
                continue;
            }
        }

        /* Associate the OF node with the device structure so it
         * can be looked up later */
        of_node_get(child);
        phy->dev.of_node = child;

        /* All data is now stored in the phy struct; register it */
        rc = phy_device_register(phy);
        if (rc) {
            phy_device_free(phy);
            of_node_put(child);
            continue;
        }

        dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
            child->name, addr);
    }

    return 0;
}
EXPORT_SYMBOL(of_mdiobus_register);

/* Helper function for of_phy_find_device */
static int of_phy_match(struct device *dev, void *phy_np)
{
    return dev->of_node == phy_np;
}

struct phy_device *of_phy_find_device(struct device_node *phy_np)
{
    struct device *d;
    if (!phy_np)
        return NULL;

    d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
    return d ? to_phy_device(d) : NULL;
}
EXPORT_SYMBOL(of_phy_find_device);

struct phy_device *of_phy_connect(struct net_device *dev,
                  struct device_node *phy_np,
                  void (*hndlr)(struct net_device *), u32 flags,
                  phy_interface_t iface)
{
    struct phy_device *phy = of_phy_find_device(phy_np);

    if (!phy)
        return NULL;

    return phy_connect_direct(dev, phy, hndlr, flags, iface) ? NULL : phy;
}
EXPORT_SYMBOL(of_phy_connect);

struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
                         void (*hndlr)(struct net_device *),
                         phy_interface_t iface)
{
    struct device_node *net_np;
    char bus_id[MII_BUS_ID_SIZE + 3];
    struct phy_device *phy;
    const __be32 *phy_id;
    int sz;

    if (!dev->dev.parent)
        return NULL;

    net_np = dev->dev.parent->of_node;
    if (!net_np)
        return NULL;

    phy_id = of_get_property(net_np, "fixed-link", &sz);
    if (!phy_id || sz < sizeof(*phy_id))
        return NULL;

    sprintf(bus_id, PHY_ID_FMT, "fixed-0", be32_to_cpu(phy_id[0]));

    phy = phy_connect(dev, bus_id, hndlr, 0, iface);
    return IS_ERR(phy) ? NULL : phy;
}
EXPORT_SYMBOL(of_phy_connect_fixed_link);