linux/drivers/of/of_mdio.c
Sebastian Hesselbarth 058112c7ef net: of_mdio: fix behavior on missing phy device
of_mdiobus_register creates a phy_device even if get_phy_device failed
to create it previously. This causes indefinite polling on non-existent
PHYs. This fix makes of_mdio_register rely on get_phy_device to
properly create the device or fail otherwise.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-08 13:13:29 -07:00

250 lines
6.3 KiB
C

/*
* 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 <grant.likely@secretlab.ca>");
MODULE_LICENSE("GPL");
/**
* of_mdiobus_register - Register mii_bus and create PHYs from the device tree
* @mdio: pointer to mii_bus structure
* @np: pointer to device_node of MDIO bus.
*
* This function registers the mii_bus structure and registers a phy_device
* for each child node of @np.
*/
int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
{
struct phy_device *phy;
struct device_node *child;
const __be32 *paddr;
u32 addr;
bool is_c45, scanphys = false;
int rc, i, len;
/* 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_available_child_of_node(np, child) {
/* A PHY must have a reg property in the range [0-31] */
paddr = of_get_property(child, "reg", &len);
if (!paddr || len < sizeof(*paddr)) {
scanphys = true;
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)) {
dev_err(&mdio->dev,
"cannot get 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);
}
if (!scanphys)
return 0;
/* auto scan for PHYs with empty reg property */
for_each_available_child_of_node(np, child) {
/* Skip PHYs with reg property set */
paddr = of_get_property(child, "reg", &len);
if (paddr)
continue;
is_c45 = of_device_is_compatible(child,
"ethernet-phy-ieee802.3-c45");
for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
/* skip already registered PHYs */
if (mdio->phy_map[addr])
continue;
/* be noisy to encourage people to set reg property */
dev_info(&mdio->dev, "scan phy %s at address %i\n",
child->name, addr);
phy = get_phy_device(mdio, addr, is_c45);
if (!phy || IS_ERR(phy))
continue;
if (mdio->irq) {
mdio->irq[addr] =
irq_of_parse_and_map(child, 0);
if (!mdio->irq[addr])
mdio->irq[addr] = PHY_POLL;
}
/* 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_info(&mdio->dev, "registered phy %s at address %i\n",
child->name, addr);
break;
}
}
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;
}
/**
* of_phy_find_device - Give a PHY node, find the phy_device
* @phy_np: Pointer to the phy's device tree node
*
* Returns a pointer to the phy_device.
*/
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);
/**
* of_phy_connect - Connect to the phy described in the device tree
* @dev: pointer to net_device claiming the phy
* @phy_np: Pointer to device tree node for the PHY
* @hndlr: Link state callback for the network device
* @iface: PHY data interface type
*
* Returns a pointer to the phy_device if successful. NULL otherwise
*/
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, iface) ? NULL : phy;
}
EXPORT_SYMBOL(of_phy_connect);
/**
* of_phy_connect_fixed_link - Parse fixed-link property and return a dummy phy
* @dev: pointer to net_device claiming the phy
* @hndlr: Link state callback for the network device
* @iface: PHY data interface type
*
* This function is a temporary stop-gap and will be removed soon. It is
* only to support the fs_enet, ucc_geth and gianfar Ethernet drivers. Do
* not call this function from new drivers.
*/
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, iface);
return IS_ERR(phy) ? NULL : phy;
}
EXPORT_SYMBOL(of_phy_connect_fixed_link);