// SPDX-License-Identifier: GPL-2.0-only
/*
* OF helpers for the MDIO (Ethernet PHY) API
*
* Copyright (c) 2009 Secret Lab Technologies, Ltd.
*
* 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/phy_fixed.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
#include <linux/module.h>
#define DEFAULT_GPIO_RESET_DELAY 10 /* in microseconds */
MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
MODULE_LICENSE("GPL");
/* Extract the clause 22 phy ID from the compatible string of the form
* ethernet-phy-idAAAA.BBBB */
static int of_get_phy_id(struct device_node *device, u32 *phy_id)
{
struct property *prop;
const char *cp;
unsigned int upper, lower;
of_property_for_each_string(device, "compatible", prop, cp) {
if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
*phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
return 0;
}
}
return -EINVAL;
}
static int of_mdiobus_register_phy(struct mii_bus *mdio,
struct device_node *child, u32 addr)
{
struct phy_device *phy;
bool is_c45;
int rc;
u32 phy_id;
is_c45 = of_device_is_compatible(child,
"ethernet-phy-ieee802.3-c45");
if (!is_c45 && !of_get_phy_id(child, &phy_id))
phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
else
phy = get_phy_device(mdio, addr, is_c45);
if (IS_ERR(phy))
return PTR_ERR(phy);
rc = of_irq_get(child, 0);
if (rc == -EPROBE_DEFER) {
phy_device_free(phy);
return rc;
}
if (rc > 0) {
phy->irq = rc;
mdio->irq[addr] = rc;
} else {
phy->irq = mdio->irq[addr];
}
if (of_property_read_bool(child, "broken-turn-around"))
mdio->phy_ignore_ta_mask |= 1 << addr;
of_property_read_u32(child, "reset-assert-us",
&phy->mdio.reset_assert_delay);
of_property_read_u32(child, "reset-deassert-us",
&phy->mdio.reset_deassert_delay);
/* Associate the OF node with the device structure so it
* can be looked up later */
of_node_get(child);
phy->mdio.dev.of_node = child;
phy->mdio.dev.fwnode = of_fwnode_handle(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);
return rc;
}
dev_dbg(&mdio->dev, "registered phy %pOFn at address %i\n",
child, addr);
return 0;
}
static int of_mdiobus_register_device(struct mii_bus *mdio,
struct device_node *child, u32 addr)
{
struct mdio_device *mdiodev;
int rc;
mdiodev = mdio_device_create(mdio, addr);
if (IS_ERR(mdiodev))
return PTR_ERR(mdiodev);
/* Associate the OF node with the device structure so it
* can be looked up later.
*/
of_node_get(child);
mdiodev->dev.of_node = child;
mdiodev->dev.fwnode = of_fwnode_handle(child);
/* All data is now stored in the mdiodev struct; register it. */
rc = mdio_device_register(mdiodev);
if (rc) {
mdio_device_free(mdiodev);
of_node_put(child);
return rc;
}
dev_dbg(&mdio->dev, "registered mdio device %pOFn at address %i\n",
child, addr);
return 0;
}
/* The following is a list of PHY compatible strings which appear in
* some DTBs. The compatible string is never matched against a PHY
* driver, so is pointless. We only expect devices which are not PHYs
* to have a compatible string, so they can be matched to an MDIO
* driver. Encourage users to upgrade their DT blobs to remove these.
*/
static const struct of_device_id whitelist_phys[] = {
{ .compatible = "brcm,40nm-ephy" },
{ .compatible = "broadcom,bcm5241" },
{ .compatible = "marvell,88E1111", },
{ .compatible = "marvell,88e1116", },
{ .compatible = "marvell,88e1118", },
{ .compatible = "marvell,88e1145", },
{ .compatible = "marvell,88e1149r", },
{ .compatible = "marvell,88e1310", },
{ .compatible = "marvell,88E1510", },
{ .compatible = "marvell,88E1514", },
{ .compatible = "moxa,moxart-rtl8201cp", },
{}
};
/*
* Return true if the child node is for a phy. It must either:
* o Compatible string of "ethernet-phy-idX.X"
* o Compatible string of "ethernet-phy-ieee802.3-c45"
* o Compatible string of "ethernet-phy-ieee802.3-c22"
* o In the white list above (and issue a warning)
* o No compatibility string
*
* A device which is not a phy is expected to have a compatible string
* indicating what sort of device it is.
*/
static bool of_mdiobus_child_is_phy(struct device_node *child)
{
u32 phy_id;
if (of_get_phy_id(child, &phy_id) != -EINVAL)
return true;
if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"))
return true;
if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22"))
return true;
if (of_match_node(whitelist_phys, child)) {
pr_warn(FW_WARN
"%pOF: Whitelisted compatible string. Please remove\n",
child);
return true;
}
if (!of_find_property(child, "compatible", NULL))
return true;
return false;
}
/**
* 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 device_node *child;
bool scanphys = false;
int addr, rc;
if (!np)
return mdiobus_register(mdio);
/* Do not continue if the node is disabled */
if (!of_device_is_available(np))
return -ENODEV;
/* 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;
mdio->dev.of_node = np;
mdio->dev.fwnode = of_fwnode_handle(np);
/* Get bus level PHY reset GPIO details */
mdio->reset_delay_us = DEFAULT_GPIO_RESET_DELAY;
of_property_read_u32(np, "reset-delay-us", &mdio->reset_delay_us);
/* Register the MDIO bus */
rc = mdiobus_register(mdio);
if (rc)
return rc;
/* Loop over the child nodes and register a phy_device for each phy */
for_each_available_child_of_node(np, child) {
addr = of_mdio_parse_addr(&mdio->dev, child);
if (addr < 0) {
scanphys = true;
continue;
}
if (of_mdiobus_child_is_phy(child))
rc = of_mdiobus_register_phy(mdio, child, addr);
else
rc = of_mdiobus_register_device(mdio, child, addr);
if (rc == -ENODEV)
dev_err(&mdio->dev,
"MDIO device at address %d is missing.\n",
addr);
else if (rc)
goto unregister;
}
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 */
if (of_find_property(child, "reg", NULL))
continue;
for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
/* skip already registered PHYs */
if (mdiobus_is_registered_device(mdio, addr))
continue;
/* be noisy to encourage people to set reg property */
dev_info(&mdio->dev, "scan phy %pOFn at address %i\n",
child, addr);
if (of_mdiobus_child_is_phy(child)) {
rc = of_mdiobus_register_phy(mdio, child, addr);
if (rc && rc != -ENODEV)
goto unregister;
}
}
}
return 0;
unregister:
mdiobus_unregister(mdio);
return rc;
}
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
*
* If successful, returns a pointer to the phy_device with the embedded
* struct device refcount incremented by one, or NULL on failure.
*/
struct phy_device *of_phy_find_device(struct device_node *phy_np)
{
struct device *d;
struct mdio_device *mdiodev;
if (!phy_np)
return NULL;
d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
if (d) {
mdiodev = to_mdio_device(d);
if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY)
return to_phy_device(d);
put_device(d);
}
return 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
* @flags: flags to pass to the PHY
* @iface: PHY data interface type
*
* If successful, returns a pointer to the phy_device with the embedded
* struct device refcount incremented by one, or NULL on failure. The
* refcount must be dropped by calling phy_disconnect() or phy_detach().
*/
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);
int ret;
if (!phy)
return NULL;
phy->dev_flags = flags;
ret = phy_connect_direct(dev, phy, hndlr, iface);
/* refcount is held by phy_connect_direct() on success */
put_device(&phy->mdio.dev);
return ret ? NULL : phy;
}
EXPORT_SYMBOL(of_phy_connect);
/**
* of_phy_get_and_connect
* - Get phy node and connect to the phy described in the device tree
* @dev: pointer to net_device claiming the phy
* @np: Pointer to device tree node for the net_device claiming the phy
* @hndlr: Link state callback for the network device
*
* If successful, returns a pointer to the phy_device with the embedded
* struct device refcount incremented by one, or NULL on failure. The
* refcount must be dropped by calling phy_disconnect() or phy_detach().
*/
struct phy_device *of_phy_get_and_connect(struct net_device *dev,
struct device_node *np,
void (*hndlr)(struct net_device *))
{
phy_interface_t iface;
struct device_node *phy_np;
struct phy_device *phy;
int ret;
iface = of_get_phy_mode(np);
if (iface < 0)
return NULL;
if (of_phy_is_fixed_link(np)) {
ret = of_phy_register_fixed_link(np);
if (ret < 0) {
netdev_err(dev, "broken fixed-link specification\n");
return NULL;
}
phy_np = of_node_get(np);
} else {
phy_np = of_parse_phandle(np, "phy-handle", 0);
if (!phy_np)
return NULL;
}
phy = of_phy_connect(dev, phy_np, hndlr, 0, iface);
of_node_put(phy_np);
return phy;
}
EXPORT_SYMBOL(of_phy_get_and_connect);
/**
* of_phy_attach - Attach to a PHY without starting the state machine
* @dev: pointer to net_device claiming the phy
* @phy_np: Node pointer for the PHY
* @flags: flags to pass to the PHY
* @iface: PHY data interface type
*
* If successful, returns a pointer to the phy_device with the embedded
* struct device refcount incremented by one, or NULL on failure. The
* refcount must be dropped by calling phy_disconnect() or phy_detach().
*/
struct phy_device *of_phy_attach(struct net_device *dev,
struct device_node *phy_np, u32 flags,
phy_interface_t iface)
{
struct phy_device *phy = of_phy_find_device(phy_np);
int ret;
if (!phy)
return NULL;
ret = phy_attach_direct(dev, phy, flags, iface);
/* refcount is held by phy_attach_direct() on success */
put_device(&phy->mdio.dev);
return ret ? NULL : phy;
}
EXPORT_SYMBOL(of_phy_attach);
/*
* of_phy_is_fixed_link() and of_phy_register_fixed_link() must
* support two DT bindings:
* - the old DT binding, where 'fixed-link' was a property with 5
* cells encoding various informations about the fixed PHY
* - the new DT binding, where 'fixed-link' is a sub-node of the
* Ethernet device.
*/
bool of_phy_is_fixed_link(struct device_node *np)
{
struct device_node *dn;
int len, err;
const char *managed;
/* New binding */
dn = of_get_child_by_name(np, "fixed-link");
if (dn) {
of_node_put(dn);
return true;
}
err = of_property_read_string(np, "managed", &managed);
if (err == 0 && strcmp(managed, "auto") != 0)
return true;
/* Old binding */
if (of_get_property(np, "fixed-link", &len) &&
len == (5 * sizeof(__be32)))
return true;
return false;
}
EXPORT_SYMBOL(of_phy_is_fixed_link);
int of_phy_register_fixed_link(struct device_node *np)
{
struct fixed_phy_status status = {};
struct device_node *fixed_link_node;
u32 fixed_link_prop[5];
const char *managed;
if (of_property_read_string(np, "managed", &managed) == 0 &&
strcmp(managed, "in-band-status") == 0) {
/* status is zeroed, namely its .link member */
goto register_phy;
}
/* New binding */
fixed_link_node = of_get_child_by_name(np, "fixed-link");
if (fixed_link_node) {
status.link = 1;
status.duplex = of_property_read_bool(fixed_link_node,
"full-duplex");
if (of_property_read_u32(fixed_link_node, "speed",
&status.speed)) {
of_node_put(fixed_link_node);
return -EINVAL;
}
status.pause = of_property_read_bool(fixed_link_node, "pause");
status.asym_pause = of_property_read_bool(fixed_link_node,
"asym-pause");
of_node_put(fixed_link_node);
goto register_phy;
}
/* Old binding */
if (of_property_read_u32_array(np, "fixed-link", fixed_link_prop,
ARRAY_SIZE(fixed_link_prop)) == 0) {
status.link = 1;
status.duplex = fixed_link_prop[1];
status.speed = fixed_link_prop[2];
status.pause = fixed_link_prop[3];
status.asym_pause = fixed_link_prop[4];
goto register_phy;
}
return -ENODEV;
register_phy:
return PTR_ERR_OR_ZERO(fixed_phy_register(PHY_POLL, &status, np));
}
EXPORT_SYMBOL(of_phy_register_fixed_link);
void of_phy_deregister_fixed_link(struct device_node *np)
{
struct phy_device *phydev;
phydev = of_phy_find_device(np);
if (!phydev)
return;
fixed_phy_unregister(phydev);
put_device(&phydev->mdio.dev); /* of_phy_find_device() */
phy_device_free(phydev); /* fixed_phy_register() */
}
EXPORT_SYMBOL(of_phy_deregister_fixed_link);
