blob: 757e950fb745bb4c5869c93f9669ee634de7843c [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/* MDIO Bus interface
*
* Author: Andy Fleming
*
* Copyright (c) 2004 Freescale Semiconductor, Inc.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mii.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/of_mdio.h>
#include <linux/phy.h>
#include <linux/reset.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/uaccess.h>
#include <linux/unistd.h>
#define CREATE_TRACE_POINTS
#include <trace/events/mdio.h>
#include "mdio-boardinfo.h"
static int mdiobus_register_gpiod(struct mdio_device *mdiodev)
{
/* Deassert the optional reset signal */
mdiodev->reset_gpio = gpiod_get_optional(&mdiodev->dev,
"reset", GPIOD_OUT_LOW);
if (IS_ERR(mdiodev->reset_gpio))
return PTR_ERR(mdiodev->reset_gpio);
if (mdiodev->reset_gpio)
gpiod_set_consumer_name(mdiodev->reset_gpio, "PHY reset");
return 0;
}
static int mdiobus_register_reset(struct mdio_device *mdiodev)
{
struct reset_control *reset;
reset = reset_control_get_optional_exclusive(&mdiodev->dev, "phy");
if (IS_ERR(reset))
return PTR_ERR(reset);
mdiodev->reset_ctrl = reset;
return 0;
}
int mdiobus_register_device(struct mdio_device *mdiodev)
{
int err;
if (mdiodev->bus->mdio_map[mdiodev->addr])
return -EBUSY;
if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY) {
err = mdiobus_register_gpiod(mdiodev);
if (err)
return err;
err = mdiobus_register_reset(mdiodev);
if (err)
return err;
/* Assert the reset signal */
mdio_device_reset(mdiodev, 1);
}
mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
return 0;
}
EXPORT_SYMBOL(mdiobus_register_device);
int mdiobus_unregister_device(struct mdio_device *mdiodev)
{
if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
return -EINVAL;
reset_control_put(mdiodev->reset_ctrl);
mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
return 0;
}
EXPORT_SYMBOL(mdiobus_unregister_device);
struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr)
{
struct mdio_device *mdiodev = bus->mdio_map[addr];
if (!mdiodev)
return NULL;
if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY))
return NULL;
return container_of(mdiodev, struct phy_device, mdio);
}
EXPORT_SYMBOL(mdiobus_get_phy);
bool mdiobus_is_registered_device(struct mii_bus *bus, int addr)
{
return bus->mdio_map[addr];
}
EXPORT_SYMBOL(mdiobus_is_registered_device);
/**
* mdiobus_alloc_size - allocate a mii_bus structure
* @size: extra amount of memory to allocate for private storage.
* If non-zero, then bus->priv is points to that memory.
*
* Description: called by a bus driver to allocate an mii_bus
* structure to fill in.
*/
struct mii_bus *mdiobus_alloc_size(size_t size)
{
struct mii_bus *bus;
size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
size_t alloc_size;
int i;
/* If we alloc extra space, it should be aligned */
if (size)
alloc_size = aligned_size + size;
else
alloc_size = sizeof(*bus);
bus = kzalloc(alloc_size, GFP_KERNEL);
if (!bus)
return NULL;
bus->state = MDIOBUS_ALLOCATED;
if (size)
bus->priv = (void *)bus + aligned_size;
/* Initialise the interrupts to polling and 64-bit seqcounts */
for (i = 0; i < PHY_MAX_ADDR; i++) {
bus->irq[i] = PHY_POLL;
u64_stats_init(&bus->stats[i].syncp);
}
return bus;
}
EXPORT_SYMBOL(mdiobus_alloc_size);
/**
* mdiobus_release - mii_bus device release callback
* @d: the target struct device that contains the mii_bus
*
* Description: called when the last reference to an mii_bus is
* dropped, to free the underlying memory.
*/
static void mdiobus_release(struct device *d)
{
struct mii_bus *bus = to_mii_bus(d);
BUG_ON(bus->state != MDIOBUS_RELEASED &&
/* for compatibility with error handling in drivers */
bus->state != MDIOBUS_ALLOCATED);
kfree(bus);
}
struct mdio_bus_stat_attr {
int addr;
unsigned int field_offset;
};
static u64 mdio_bus_get_stat(struct mdio_bus_stats *s, unsigned int offset)
{
const char *p = (const char *)s + offset;
unsigned int start;
u64 val = 0;
do {
start = u64_stats_fetch_begin(&s->syncp);
val = u64_stats_read((const u64_stats_t *)p);
} while (u64_stats_fetch_retry(&s->syncp, start));
return val;
}
static u64 mdio_bus_get_global_stat(struct mii_bus *bus, unsigned int offset)
{
unsigned int i;
u64 val = 0;
for (i = 0; i < PHY_MAX_ADDR; i++)
val += mdio_bus_get_stat(&bus->stats[i], offset);
return val;
}
static ssize_t mdio_bus_stat_field_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct mii_bus *bus = to_mii_bus(dev);
struct mdio_bus_stat_attr *sattr;
struct dev_ext_attribute *eattr;
u64 val;
eattr = container_of(attr, struct dev_ext_attribute, attr);
sattr = eattr->var;
if (sattr->addr < 0)
val = mdio_bus_get_global_stat(bus, sattr->field_offset);
else
val = mdio_bus_get_stat(&bus->stats[sattr->addr],
sattr->field_offset);
return sprintf(buf, "%llu\n", val);
}
static ssize_t mdio_bus_device_stat_field_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct mdio_device *mdiodev = to_mdio_device(dev);
struct mii_bus *bus = mdiodev->bus;
struct mdio_bus_stat_attr *sattr;
struct dev_ext_attribute *eattr;
int addr = mdiodev->addr;
u64 val;
eattr = container_of(attr, struct dev_ext_attribute, attr);
sattr = eattr->var;
val = mdio_bus_get_stat(&bus->stats[addr], sattr->field_offset);
return sprintf(buf, "%llu\n", val);
}
#define MDIO_BUS_STATS_ATTR_DECL(field, file) \
static struct dev_ext_attribute dev_attr_mdio_bus_##field = { \
.attr = { .attr = { .name = file, .mode = 0444 }, \
.show = mdio_bus_stat_field_show, \
}, \
.var = &((struct mdio_bus_stat_attr) { \
-1, offsetof(struct mdio_bus_stats, field) \
}), \
}; \
static struct dev_ext_attribute dev_attr_mdio_bus_device_##field = { \
.attr = { .attr = { .name = file, .mode = 0444 }, \
.show = mdio_bus_device_stat_field_show, \
}, \
.var = &((struct mdio_bus_stat_attr) { \
-1, offsetof(struct mdio_bus_stats, field) \
}), \
};
#define MDIO_BUS_STATS_ATTR(field) \
MDIO_BUS_STATS_ATTR_DECL(field, __stringify(field))
MDIO_BUS_STATS_ATTR(transfers);
MDIO_BUS_STATS_ATTR(errors);
MDIO_BUS_STATS_ATTR(writes);
MDIO_BUS_STATS_ATTR(reads);
#define MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, file) \
static struct dev_ext_attribute dev_attr_mdio_bus_addr_##field##_##addr = { \
.attr = { .attr = { .name = file, .mode = 0444 }, \
.show = mdio_bus_stat_field_show, \
}, \
.var = &((struct mdio_bus_stat_attr) { \
addr, offsetof(struct mdio_bus_stats, field) \
}), \
}
#define MDIO_BUS_STATS_ADDR_ATTR(field, addr) \
MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, \
__stringify(field) "_" __stringify(addr))
#define MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(addr) \
MDIO_BUS_STATS_ADDR_ATTR(transfers, addr); \
MDIO_BUS_STATS_ADDR_ATTR(errors, addr); \
MDIO_BUS_STATS_ADDR_ATTR(writes, addr); \
MDIO_BUS_STATS_ADDR_ATTR(reads, addr) \
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(0);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(1);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(2);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(3);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(4);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(5);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(6);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(7);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(8);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(9);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(10);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(11);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(12);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(13);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(14);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(15);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(16);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(17);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(18);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(19);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(20);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(21);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(22);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(23);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(24);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(25);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(26);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(27);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(28);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(29);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(30);
MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(31);
#define MDIO_BUS_STATS_ADDR_ATTR_GROUP(addr) \
&dev_attr_mdio_bus_addr_transfers_##addr.attr.attr, \
&dev_attr_mdio_bus_addr_errors_##addr.attr.attr, \
&dev_attr_mdio_bus_addr_writes_##addr.attr.attr, \
&dev_attr_mdio_bus_addr_reads_##addr.attr.attr \
static struct attribute *mdio_bus_statistics_attrs[] = {
&dev_attr_mdio_bus_transfers.attr.attr,
&dev_attr_mdio_bus_errors.attr.attr,
&dev_attr_mdio_bus_writes.attr.attr,
&dev_attr_mdio_bus_reads.attr.attr,
MDIO_BUS_STATS_ADDR_ATTR_GROUP(0),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(1),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(2),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(3),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(4),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(5),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(6),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(7),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(8),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(9),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(10),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(11),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(12),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(13),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(14),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(15),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(16),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(17),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(18),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(19),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(20),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(21),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(22),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(23),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(24),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(25),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(26),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(27),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(28),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(29),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(30),
MDIO_BUS_STATS_ADDR_ATTR_GROUP(31),
NULL,
};
static const struct attribute_group mdio_bus_statistics_group = {
.name = "statistics",
.attrs = mdio_bus_statistics_attrs,
};
static const struct attribute_group *mdio_bus_groups[] = {
&mdio_bus_statistics_group,
NULL,
};
static struct class mdio_bus_class = {
.name = "mdio_bus",
.dev_release = mdiobus_release,
.dev_groups = mdio_bus_groups,
};
/**
* mdio_find_bus - Given the name of a mdiobus, find the mii_bus.
* @mdio_name: The name of a mdiobus.
*
* Returns a reference to the mii_bus, or NULL if none found. The
* embedded struct device will have its reference count incremented,
* and this must be put_deviced'ed once the bus is finished with.
*/
struct mii_bus *mdio_find_bus(const char *mdio_name)
{
struct device *d;
d = class_find_device_by_name(&mdio_bus_class, mdio_name);
return d ? to_mii_bus(d) : NULL;
}
EXPORT_SYMBOL(mdio_find_bus);
#if IS_ENABLED(CONFIG_OF_MDIO)
/**
* of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
* @mdio_bus_np: Pointer to the mii_bus.
*
* Returns a reference to the mii_bus, or NULL if none found. The
* embedded struct device will have its reference count incremented,
* and this must be put once the bus is finished with.
*
* Because the association of a device_node and mii_bus is made via
* of_mdiobus_register(), the mii_bus cannot be found before it is
* registered with of_mdiobus_register().
*
*/
struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
{
struct device *d;
if (!mdio_bus_np)
return NULL;
d = class_find_device_by_of_node(&mdio_bus_class, mdio_bus_np);
return d ? to_mii_bus(d) : NULL;
}
EXPORT_SYMBOL(of_mdio_find_bus);
/* Walk the list of subnodes of a mdio bus and look for a node that
* matches the mdio device's address with its 'reg' property. If
* found, set the of_node pointer for the mdio device. This allows
* auto-probed phy devices to be supplied with information passed in
* via DT.
*/
static void of_mdiobus_link_mdiodev(struct mii_bus *bus,
struct mdio_device *mdiodev)
{
struct device *dev = &mdiodev->dev;
struct device_node *child;
if (dev->of_node || !bus->dev.of_node)
return;
for_each_available_child_of_node(bus->dev.of_node, child) {
int addr;
addr = of_mdio_parse_addr(dev, child);
if (addr < 0)
continue;
if (addr == mdiodev->addr) {
dev->of_node = child;
dev->fwnode = of_fwnode_handle(child);
return;
}
}
}
#else /* !IS_ENABLED(CONFIG_OF_MDIO) */
static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio,
struct mdio_device *mdiodev)
{
}
#endif
/**
* mdiobus_create_device_from_board_info - create a full MDIO device given
* a mdio_board_info structure
* @bus: MDIO bus to create the devices on
* @bi: mdio_board_info structure describing the devices
*
* Returns 0 on success or < 0 on error.
*/
static int mdiobus_create_device(struct mii_bus *bus,
struct mdio_board_info *bi)
{
struct mdio_device *mdiodev;
int ret = 0;
mdiodev = mdio_device_create(bus, bi->mdio_addr);
if (IS_ERR(mdiodev))
return -ENODEV;
strncpy(mdiodev->modalias, bi->modalias,
sizeof(mdiodev->modalias));
mdiodev->bus_match = mdio_device_bus_match;
mdiodev->dev.platform_data = (void *)bi->platform_data;
ret = mdio_device_register(mdiodev);
if (ret)
mdio_device_free(mdiodev);
return ret;
}
/**
* __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
* @bus: target mii_bus
* @owner: module containing bus accessor functions
*
* Description: Called by a bus driver to bring up all the PHYs
* on a given bus, and attach them to the bus. Drivers should use
* mdiobus_register() rather than __mdiobus_register() unless they
* need to pass a specific owner module. MDIO devices which are not
* PHYs will not be brought up by this function. They are expected to
* to be explicitly listed in DT and instantiated by of_mdiobus_register().
*
* Returns 0 on success or < 0 on error.
*/
int __mdiobus_register(struct mii_bus *bus, struct module *owner)
{
struct mdio_device *mdiodev;
int i, err;
struct gpio_desc *gpiod;
if (NULL == bus || NULL == bus->name ||
NULL == bus->read || NULL == bus->write)
return -EINVAL;
BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
bus->state != MDIOBUS_UNREGISTERED);
bus->owner = owner;
bus->dev.parent = bus->parent;
bus->dev.class = &mdio_bus_class;
bus->dev.groups = NULL;
dev_set_name(&bus->dev, "%s", bus->id);
err = device_register(&bus->dev);
if (err) {
pr_err("mii_bus %s failed to register\n", bus->id);
return -EINVAL;
}
mutex_init(&bus->mdio_lock);
mutex_init(&bus->shared_lock);
/* de-assert bus level PHY GPIO reset */
gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_LOW);
if (IS_ERR(gpiod)) {
dev_err(&bus->dev, "mii_bus %s couldn't get reset GPIO\n",
bus->id);
device_del(&bus->dev);
return PTR_ERR(gpiod);
} else if (gpiod) {
bus->reset_gpiod = gpiod;
gpiod_set_value_cansleep(gpiod, 1);
fsleep(bus->reset_delay_us);
gpiod_set_value_cansleep(gpiod, 0);
if (bus->reset_post_delay_us > 0)
fsleep(bus->reset_post_delay_us);
}
if (bus->reset) {
err = bus->reset(bus);
if (err)
goto error_reset_gpiod;
}
for (i = 0; i < PHY_MAX_ADDR; i++) {
if ((bus->phy_mask & (1 << i)) == 0) {
struct phy_device *phydev;
phydev = mdiobus_scan(bus, i);
if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) {
err = PTR_ERR(phydev);
goto error;
}
}
}
mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device);
bus->state = MDIOBUS_REGISTERED;
pr_info("%s: probed\n", bus->name);
return 0;
error:
while (--i >= 0) {
mdiodev = bus->mdio_map[i];
if (!mdiodev)
continue;
mdiodev->device_remove(mdiodev);
mdiodev->device_free(mdiodev);
}
error_reset_gpiod:
/* Put PHYs in RESET to save power */
if (bus->reset_gpiod)
gpiod_set_value_cansleep(bus->reset_gpiod, 1);
device_del(&bus->dev);
return err;
}
EXPORT_SYMBOL(__mdiobus_register);
void mdiobus_unregister(struct mii_bus *bus)
{
struct mdio_device *mdiodev;
int i;
BUG_ON(bus->state != MDIOBUS_REGISTERED);
bus->state = MDIOBUS_UNREGISTERED;
for (i = 0; i < PHY_MAX_ADDR; i++) {
mdiodev = bus->mdio_map[i];
if (!mdiodev)
continue;
if (mdiodev->reset_gpio)
gpiod_put(mdiodev->reset_gpio);
mdiodev->device_remove(mdiodev);
mdiodev->device_free(mdiodev);
}
/* Put PHYs in RESET to save power */
if (bus->reset_gpiod)
gpiod_set_value_cansleep(bus->reset_gpiod, 1);
device_del(&bus->dev);
}
EXPORT_SYMBOL(mdiobus_unregister);
/**
* mdiobus_free - free a struct mii_bus
* @bus: mii_bus to free
*
* This function releases the reference to the underlying device
* object in the mii_bus. If this is the last reference, the mii_bus
* will be freed.
*/
void mdiobus_free(struct mii_bus *bus)
{
/* For compatibility with error handling in drivers. */
if (bus->state == MDIOBUS_ALLOCATED) {
kfree(bus);
return;
}
BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
bus->state = MDIOBUS_RELEASED;
put_device(&bus->dev);
}
EXPORT_SYMBOL(mdiobus_free);
/**
* mdiobus_scan - scan a bus for MDIO devices.
* @bus: mii_bus to scan
* @addr: address on bus to scan
*
* This function scans the MDIO bus, looking for devices which can be
* identified using a vendor/product ID in registers 2 and 3. Not all
* MDIO devices have such registers, but PHY devices typically
* do. Hence this function assumes anything found is a PHY, or can be
* treated as a PHY. Other MDIO devices, such as switches, will
* probably not be found during the scan.
*/
struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
{
struct phy_device *phydev = ERR_PTR(-ENODEV);
int err;
switch (bus->probe_capabilities) {
case MDIOBUS_NO_CAP:
case MDIOBUS_C22:
phydev = get_phy_device(bus, addr, false);
break;
case MDIOBUS_C45:
phydev = get_phy_device(bus, addr, true);
break;
case MDIOBUS_C22_C45:
phydev = get_phy_device(bus, addr, false);
if (IS_ERR(phydev))
phydev = get_phy_device(bus, addr, true);
break;
}
if (IS_ERR(phydev))
return phydev;
/*
* For DT, see if the auto-probed phy has a correspoding child
* in the bus node, and set the of_node pointer in this case.
*/
of_mdiobus_link_mdiodev(bus, &phydev->mdio);
err = phy_device_register(phydev);
if (err) {
phy_device_free(phydev);
return ERR_PTR(-ENODEV);
}
return phydev;
}
EXPORT_SYMBOL(mdiobus_scan);
static void mdiobus_stats_acct(struct mdio_bus_stats *stats, bool op, int ret)
{
preempt_disable();
u64_stats_update_begin(&stats->syncp);
u64_stats_inc(&stats->transfers);
if (ret < 0) {
u64_stats_inc(&stats->errors);
goto out;
}
if (op)
u64_stats_inc(&stats->reads);
else
u64_stats_inc(&stats->writes);
out:
u64_stats_update_end(&stats->syncp);
preempt_enable();
}
/**
* __mdiobus_read - Unlocked version of the mdiobus_read function
* @bus: the mii_bus struct
* @addr: the phy address
* @regnum: register number to read
*
* Read a MDIO bus register. Caller must hold the mdio bus lock.
*
* NOTE: MUST NOT be called from interrupt context.
*/
int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
{
int retval;
WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock));
retval = bus->read(bus, addr, regnum);
trace_mdio_access(bus, 1, addr, regnum, retval, retval);
mdiobus_stats_acct(&bus->stats[addr], true, retval);
return retval;
}
EXPORT_SYMBOL(__mdiobus_read);
/**
* __mdiobus_write - Unlocked version of the mdiobus_write function
* @bus: the mii_bus struct
* @addr: the phy address
* @regnum: register number to write
* @val: value to write to @regnum
*
* Write a MDIO bus register. Caller must hold the mdio bus lock.
*
* NOTE: MUST NOT be called from interrupt context.
*/
int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
{
int err;
WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock));
err = bus->write(bus, addr, regnum, val);
trace_mdio_access(bus, 0, addr, regnum, val, err);
mdiobus_stats_acct(&bus->stats[addr], false, err);
return err;
}
EXPORT_SYMBOL(__mdiobus_write);
/**
* __mdiobus_modify_changed - Unlocked version of the mdiobus_modify function
* @bus: the mii_bus struct
* @addr: the phy address
* @regnum: register number to modify
* @mask: bit mask of bits to clear
* @set: bit mask of bits to set
*
* Read, modify, and if any change, write the register value back to the
* device. Any error returns a negative number.
*
* NOTE: MUST NOT be called from interrupt context.
*/
int __mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,
u16 mask, u16 set)
{
int new, ret;
ret = __mdiobus_read(bus, addr, regnum);
if (ret < 0)
return ret;
new = (ret & ~mask) | set;
if (new == ret)
return 0;
ret = __mdiobus_write(bus, addr, regnum, new);
return ret < 0 ? ret : 1;
}
EXPORT_SYMBOL_GPL(__mdiobus_modify_changed);
/**
* mdiobus_read_nested - Nested version of the mdiobus_read function
* @bus: the mii_bus struct
* @addr: the phy address
* @regnum: register number to read
*
* In case of nested MDIO bus access avoid lockdep false positives by
* using mutex_lock_nested().
*
* NOTE: MUST NOT be called from interrupt context,
* because the bus read/write functions may wait for an interrupt
* to conclude the operation.
*/
int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)
{
int retval;
mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
retval = __mdiobus_read(bus, addr, regnum);
mutex_unlock(&bus->mdio_lock);
return retval;
}
EXPORT_SYMBOL(mdiobus_read_nested);
/**
* mdiobus_read - Convenience function for reading a given MII mgmt register
* @bus: the mii_bus struct
* @addr: the phy address
* @regnum: register number to read
*
* NOTE: MUST NOT be called from interrupt context,
* because the bus read/write functions may wait for an interrupt
* to conclude the operation.
*/
int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
{
int retval;
mutex_lock(&bus->mdio_lock);
retval = __mdiobus_read(bus, addr, regnum);
mutex_unlock(&bus->mdio_lock);
return retval;
}
EXPORT_SYMBOL(mdiobus_read);
/**
* mdiobus_write_nested - Nested version of the mdiobus_write function
* @bus: the mii_bus struct
* @addr: the phy address
* @regnum: register number to write
* @val: value to write to @regnum
*
* In case of nested MDIO bus access avoid lockdep false positives by
* using mutex_lock_nested().
*
* NOTE: MUST NOT be called from interrupt context,
* because the bus read/write functions may wait for an interrupt
* to conclude the operation.
*/
int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)
{
int err;
mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
err = __mdiobus_write(bus, addr, regnum, val);
mutex_unlock(&bus->mdio_lock);
return err;
}
EXPORT_SYMBOL(mdiobus_write_nested);
/**
* mdiobus_write - Convenience function for writing a given MII mgmt register
* @bus: the mii_bus struct
* @addr: the phy address
* @regnum: register number to write
* @val: value to write to @regnum
*
* NOTE: MUST NOT be called from interrupt context,
* because the bus read/write functions may wait for an interrupt
* to conclude the operation.
*/
int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
{
int err;
mutex_lock(&bus->mdio_lock);
err = __mdiobus_write(bus, addr, regnum, val);
mutex_unlock(&bus->mdio_lock);
return err;
}
EXPORT_SYMBOL(mdiobus_write);
/**
* mdiobus_modify - Convenience function for modifying a given mdio device
* register
* @bus: the mii_bus struct
* @addr: the phy address
* @regnum: register number to write
* @mask: bit mask of bits to clear
* @set: bit mask of bits to set
*/
int mdiobus_modify(struct mii_bus *bus, int addr, u32 regnum, u16 mask, u16 set)
{
int err;
mutex_lock(&bus->mdio_lock);
err = __mdiobus_modify_changed(bus, addr, regnum, mask, set);
mutex_unlock(&bus->mdio_lock);
return err < 0 ? err : 0;
}
EXPORT_SYMBOL_GPL(mdiobus_modify);
/**
* mdio_bus_match - determine if given MDIO driver supports the given
* MDIO device
* @dev: target MDIO device
* @drv: given MDIO driver
*
* Description: Given a MDIO device, and a MDIO driver, return 1 if
* the driver supports the device. Otherwise, return 0. This may
* require calling the devices own match function, since different classes
* of MDIO devices have different match criteria.
*/
static int mdio_bus_match(struct device *dev, struct device_driver *drv)
{
struct mdio_device *mdio = to_mdio_device(dev);
if (of_driver_match_device(dev, drv))
return 1;
if (mdio->bus_match)
return mdio->bus_match(dev, drv);
return 0;
}
static int mdio_uevent(struct device *dev, struct kobj_uevent_env *env)
{
int rc;
/* Some devices have extra OF data and an OF-style MODALIAS */
rc = of_device_uevent_modalias(dev, env);
if (rc != -ENODEV)
return rc;
return 0;
}
static struct attribute *mdio_bus_device_statistics_attrs[] = {
&dev_attr_mdio_bus_device_transfers.attr.attr,
&dev_attr_mdio_bus_device_errors.attr.attr,
&dev_attr_mdio_bus_device_writes.attr.attr,
&dev_attr_mdio_bus_device_reads.attr.attr,
NULL,
};
static const struct attribute_group mdio_bus_device_statistics_group = {
.name = "statistics",
.attrs = mdio_bus_device_statistics_attrs,
};
static const struct attribute_group *mdio_bus_dev_groups[] = {
&mdio_bus_device_statistics_group,
NULL,
};
struct bus_type mdio_bus_type = {
.name = "mdio_bus",
.dev_groups = mdio_bus_dev_groups,
.match = mdio_bus_match,
.uevent = mdio_uevent,
};
EXPORT_SYMBOL(mdio_bus_type);
int __init mdio_bus_init(void)
{
int ret;
ret = class_register(&mdio_bus_class);
if (!ret) {
ret = bus_register(&mdio_bus_type);
if (ret)
class_unregister(&mdio_bus_class);
}
return ret;
}
EXPORT_SYMBOL_GPL(mdio_bus_init);
#if IS_ENABLED(CONFIG_PHYLIB)
void mdio_bus_exit(void)
{
class_unregister(&mdio_bus_class);
bus_unregister(&mdio_bus_type);
}
EXPORT_SYMBOL_GPL(mdio_bus_exit);
#else
module_init(mdio_bus_init);
/* no module_exit, intentional */
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MDIO bus/device layer");
#endif