diff options
Diffstat (limited to 'drivers/net/phy/mdio_bus.c')
| -rw-r--r-- | drivers/net/phy/mdio_bus.c | 1422 |
1 files changed, 1422 insertions, 0 deletions
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c new file mode 100644 index 0000000000..25dcaa49ab --- /dev/null +++ b/drivers/net/phy/mdio_bus.c @@ -0,0 +1,1422 @@ +// 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/micrel_phy.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); + +static struct mdio_device *mdiobus_find_device(struct mii_bus *bus, int addr) +{ + bool addr_valid = addr >= 0 && addr < ARRAY_SIZE(bus->mdio_map); + + if (WARN_ONCE(!addr_valid, "addr %d out of range\n", addr)) + return NULL; + + return bus->mdio_map[addr]; +} + +struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr) +{ + struct mdio_device *mdiodev; + + mdiodev = mdiobus_find_device(bus, 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 mdiobus_find_device(bus, addr) != NULL; +} +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); + + WARN(bus->state != MDIOBUS_RELEASED && + /* for compatibility with error handling in drivers */ + bus->state != MDIOBUS_ALLOCATED, + "%s: not in RELEASED or ALLOCATED state\n", + bus->id); + 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 sysfs_emit(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 sysfs_emit(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) { + device_set_node(dev, of_fwnode_handle(child)); + /* The refcount on "child" is passed to the mdio + * device. Do _not_ use of_node_put(child) here. + */ + 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 - 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; +} + +static struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr, bool c45) +{ + struct phy_device *phydev = ERR_PTR(-ENODEV); + int err; + + phydev = get_phy_device(bus, addr, c45); + if (IS_ERR(phydev)) + return phydev; + + /* For DT, see if the auto-probed phy has a corresponding 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; +} + +/** + * mdiobus_scan_c22 - scan one address on a bus for C22 MDIO devices. + * @bus: mii_bus to scan + * @addr: address on bus to scan + * + * This function scans one address on 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_c22(struct mii_bus *bus, int addr) +{ + return mdiobus_scan(bus, addr, false); +} +EXPORT_SYMBOL(mdiobus_scan_c22); + +/** + * mdiobus_scan_c45 - scan one address on a bus for C45 MDIO devices. + * @bus: mii_bus to scan + * @addr: address on bus to scan + * + * This function scans one address on 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. + */ +static struct phy_device *mdiobus_scan_c45(struct mii_bus *bus, int addr) +{ + return mdiobus_scan(bus, addr, true); +} + +static int mdiobus_scan_bus_c22(struct mii_bus *bus) +{ + int i; + + for (i = 0; i < PHY_MAX_ADDR; i++) { + if ((bus->phy_mask & BIT(i)) == 0) { + struct phy_device *phydev; + + phydev = mdiobus_scan_c22(bus, i); + if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) + return PTR_ERR(phydev); + } + } + return 0; +} + +static int mdiobus_scan_bus_c45(struct mii_bus *bus) +{ + int i; + + for (i = 0; i < PHY_MAX_ADDR; i++) { + if ((bus->phy_mask & BIT(i)) == 0) { + struct phy_device *phydev; + + /* Don't scan C45 if we already have a C22 device */ + if (bus->mdio_map[i]) + continue; + + phydev = mdiobus_scan_c45(bus, i); + if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) + return PTR_ERR(phydev); + } + } + return 0; +} + +/* There are some C22 PHYs which do bad things when where is a C45 + * transaction on the bus, like accepting a read themselves, and + * stomping over the true devices reply, to performing a write to + * themselves which was intended for another device. Now that C22 + * devices have been found, see if any of them are bad for C45, and if we + * should skip the C45 scan. + */ +static bool mdiobus_prevent_c45_scan(struct mii_bus *bus) +{ + int i; + + for (i = 0; i < PHY_MAX_ADDR; i++) { + struct phy_device *phydev; + u32 oui; + + phydev = mdiobus_get_phy(bus, i); + if (!phydev) + continue; + oui = phydev->phy_id >> 10; + + if (oui == MICREL_OUI) + return true; + } + return false; +} + +/** + * __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 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; + struct gpio_desc *gpiod; + bool prevent_c45_scan; + int i, err; + + if (!bus || !bus->name) + return -EINVAL; + + /* An access method always needs both read and write operations */ + if (!!bus->read != !!bus->write || !!bus->read_c45 != !!bus->write_c45) + return -EINVAL; + + /* At least one method is mandatory */ + if (!bus->read && !bus->read_c45) + return -EINVAL; + + if (bus->parent && bus->parent->of_node) + bus->parent->of_node->fwnode.flags |= + FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD; + + WARN(bus->state != MDIOBUS_ALLOCATED && + bus->state != MDIOBUS_UNREGISTERED, + "%s: not in ALLOCATED or UNREGISTERED state\n", bus->id); + + 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); + + /* We need to set state to MDIOBUS_UNREGISTERED to correctly release + * the device in mdiobus_free() + * + * State will be updated later in this function in case of success + */ + bus->state = MDIOBUS_UNREGISTERED; + + 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); + + /* assert bus level PHY GPIO reset */ + gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(gpiod)) { + err = dev_err_probe(&bus->dev, PTR_ERR(gpiod), + "mii_bus %s couldn't get reset GPIO\n", + bus->id); + device_del(&bus->dev); + return err; + } else if (gpiod) { + bus->reset_gpiod = gpiod; + 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; + } + + if (bus->read) { + err = mdiobus_scan_bus_c22(bus); + if (err) + goto error; + } + + prevent_c45_scan = mdiobus_prevent_c45_scan(bus); + + if (!prevent_c45_scan && bus->read_c45) { + err = mdiobus_scan_bus_c45(bus); + if (err) + goto error; + } + + mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device); + + bus->state = MDIOBUS_REGISTERED; + dev_dbg(&bus->dev, "probed\n"); + return 0; + +error: + for (i = 0; i < PHY_MAX_ADDR; i++) { + 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; + + if (WARN_ON_ONCE(bus->state != MDIOBUS_REGISTERED)) + return; + 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; + } + + WARN(bus->state != MDIOBUS_UNREGISTERED, + "%s: not in UNREGISTERED state\n", bus->id); + bus->state = MDIOBUS_RELEASED; + + put_device(&bus->dev); +} +EXPORT_SYMBOL(mdiobus_free); + +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; + + lockdep_assert_held_once(&bus->mdio_lock); + + if (bus->read) + retval = bus->read(bus, addr, regnum); + else + retval = -EOPNOTSUPP; + + 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; + + lockdep_assert_held_once(&bus->mdio_lock); + + if (bus->write) + err = bus->write(bus, addr, regnum, val); + else + err = -EOPNOTSUPP; + + 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_c45_read - Unlocked version of the mdiobus_c45_read function + * @bus: the mii_bus struct + * @addr: the phy address + * @devad: device address to read + * @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_c45_read(struct mii_bus *bus, int addr, int devad, u32 regnum) +{ + int retval; + + lockdep_assert_held_once(&bus->mdio_lock); + + if (bus->read_c45) + retval = bus->read_c45(bus, addr, devad, regnum); + else + retval = -EOPNOTSUPP; + + trace_mdio_access(bus, 1, addr, regnum, retval, retval); + mdiobus_stats_acct(&bus->stats[addr], true, retval); + + return retval; +} +EXPORT_SYMBOL(__mdiobus_c45_read); + +/** + * __mdiobus_c45_write - Unlocked version of the mdiobus_write function + * @bus: the mii_bus struct + * @addr: the phy address + * @devad: device address to read + * @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_c45_write(struct mii_bus *bus, int addr, int devad, u32 regnum, + u16 val) +{ + int err; + + lockdep_assert_held_once(&bus->mdio_lock); + + if (bus->write_c45) + err = bus->write_c45(bus, addr, devad, regnum, val); + else + err = -EOPNOTSUPP; + + trace_mdio_access(bus, 0, addr, regnum, val, err); + mdiobus_stats_acct(&bus->stats[addr], false, err); + + return err; +} +EXPORT_SYMBOL(__mdiobus_c45_write); + +/** + * __mdiobus_c45_modify_changed - Unlocked version of the mdiobus_modify function + * @bus: the mii_bus struct + * @addr: the phy address + * @devad: device address to read + * @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. + */ +static int __mdiobus_c45_modify_changed(struct mii_bus *bus, int addr, + int devad, u32 regnum, u16 mask, + u16 set) +{ + int new, ret; + + ret = __mdiobus_c45_read(bus, addr, devad, regnum); + if (ret < 0) + return ret; + + new = (ret & ~mask) | set; + if (new == ret) + return 0; + + ret = __mdiobus_c45_write(bus, addr, devad, regnum, new); + + return ret < 0 ? ret : 1; +} + +/** + * 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_c45_read - Convenience function for reading a given MII mgmt register + * @bus: the mii_bus struct + * @addr: the phy address + * @devad: device address to read + * @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_c45_read(struct mii_bus *bus, int addr, int devad, u32 regnum) +{ + int retval; + + mutex_lock(&bus->mdio_lock); + retval = __mdiobus_c45_read(bus, addr, devad, regnum); + mutex_unlock(&bus->mdio_lock); + + return retval; +} +EXPORT_SYMBOL(mdiobus_c45_read); + +/** + * mdiobus_c45_read_nested - Nested version of the mdiobus_c45_read function + * @bus: the mii_bus struct + * @addr: the phy address + * @devad: device address to read + * @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_c45_read_nested(struct mii_bus *bus, int addr, int devad, + u32 regnum) +{ + int retval; + + mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED); + retval = __mdiobus_c45_read(bus, addr, devad, regnum); + mutex_unlock(&bus->mdio_lock); + + return retval; +} +EXPORT_SYMBOL(mdiobus_c45_read_nested); + +/** + * 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_c45_write - Convenience function for writing a given MII mgmt register + * @bus: the mii_bus struct + * @addr: the phy address + * @devad: device address to read + * @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_c45_write(struct mii_bus *bus, int addr, int devad, u32 regnum, + u16 val) +{ + int err; + + mutex_lock(&bus->mdio_lock); + err = __mdiobus_c45_write(bus, addr, devad, regnum, val); + mutex_unlock(&bus->mdio_lock); + + return err; +} +EXPORT_SYMBOL(mdiobus_c45_write); + +/** + * mdiobus_c45_write_nested - Nested version of the mdiobus_c45_write function + * @bus: the mii_bus struct + * @addr: the phy address + * @devad: device address to read + * @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_c45_write_nested(struct mii_bus *bus, int addr, int devad, + u32 regnum, u16 val) +{ + int err; + + mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED); + err = __mdiobus_c45_write(bus, addr, devad, regnum, val); + mutex_unlock(&bus->mdio_lock); + + return err; +} +EXPORT_SYMBOL(mdiobus_c45_write_nested); + +/* + * __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; + + err = __mdiobus_modify_changed(bus, addr, regnum, mask, set); + + return err < 0 ? err : 0; +} +EXPORT_SYMBOL_GPL(__mdiobus_modify); + +/** + * 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(bus, addr, regnum, mask, set); + mutex_unlock(&bus->mdio_lock); + + return err; +} +EXPORT_SYMBOL_GPL(mdiobus_modify); + +/** + * mdiobus_c45_modify - Convenience function for modifying a given mdio device + * register + * @bus: the mii_bus struct + * @addr: the phy address + * @devad: device address to read + * @regnum: register number to write + * @mask: bit mask of bits to clear + * @set: bit mask of bits to set + */ +int mdiobus_c45_modify(struct mii_bus *bus, int addr, int devad, u32 regnum, + u16 mask, u16 set) +{ + int err; + + mutex_lock(&bus->mdio_lock); + err = __mdiobus_c45_modify_changed(bus, addr, devad, regnum, + mask, set); + mutex_unlock(&bus->mdio_lock); + + return err < 0 ? err : 0; +} +EXPORT_SYMBOL_GPL(mdiobus_c45_modify); + +/** + * mdiobus_modify_changed - Convenience function for modifying a given mdio + * device register and returning if it changed + * @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_changed(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; +} +EXPORT_SYMBOL_GPL(mdiobus_modify_changed); + +/** + * mdiobus_c45_modify_changed - Convenience function for modifying a given mdio + * device register and returning if it changed + * @bus: the mii_bus struct + * @addr: the phy address + * @devad: device address to read + * @regnum: register number to write + * @mask: bit mask of bits to clear + * @set: bit mask of bits to set + */ +int mdiobus_c45_modify_changed(struct mii_bus *bus, int addr, int devad, + u32 regnum, u16 mask, u16 set) +{ + int err; + + mutex_lock(&bus->mdio_lock); + err = __mdiobus_c45_modify_changed(bus, addr, devad, regnum, mask, set); + mutex_unlock(&bus->mdio_lock); + + return err; +} +EXPORT_SYMBOL_GPL(mdiobus_c45_modify_changed); + +/** + * 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_driver *mdiodrv = to_mdio_driver(drv); + struct mdio_device *mdio = to_mdio_device(dev); + + /* Both the driver and device must type-match */ + if (!(mdiodrv->mdiodrv.flags & MDIO_DEVICE_IS_PHY) != + !(mdio->flags & MDIO_DEVICE_FLAG_PHY)) + return 0; + + 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(const 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; +} + +#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 |