/* MDIO Bus interface * * Author: Andy Fleming * * Copyright (c) 2004 Freescale Semiconductor, Inc. * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. * */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /** * 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; /* 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) { bus->state = MDIOBUS_ALLOCATED; if (size) bus->priv = (void *)bus + aligned_size; } return bus; } EXPORT_SYMBOL(mdiobus_alloc_size); static void _devm_mdiobus_free(struct device *dev, void *res) { mdiobus_free(*(struct mii_bus **)res); } static int devm_mdiobus_match(struct device *dev, void *res, void *data) { struct mii_bus **r = res; if (WARN_ON(!r || !*r)) return 0; return *r == data; } /** * devm_mdiobus_alloc_size - Resource-managed mdiobus_alloc_size() * @dev: Device to allocate mii_bus for * @sizeof_priv: Space to allocate for private structure. * * Managed mdiobus_alloc_size. mii_bus allocated with this function is * automatically freed on driver detach. * * If an mii_bus allocated with this function needs to be freed separately, * devm_mdiobus_free() must be used. * * RETURNS: * Pointer to allocated mii_bus on success, NULL on failure. */ struct mii_bus *devm_mdiobus_alloc_size(struct device *dev, int sizeof_priv) { struct mii_bus **ptr, *bus; ptr = devres_alloc(_devm_mdiobus_free, sizeof(*ptr), GFP_KERNEL); if (!ptr) return NULL; /* use raw alloc_dr for kmalloc caller tracing */ bus = mdiobus_alloc_size(sizeof_priv); if (bus) { *ptr = bus; devres_add(dev, ptr); } else { devres_free(ptr); } return bus; } EXPORT_SYMBOL_GPL(devm_mdiobus_alloc_size); /** * devm_mdiobus_free - Resource-managed mdiobus_free() * @dev: Device this mii_bus belongs to * @bus: the mii_bus associated with the device * * Free mii_bus allocated with devm_mdiobus_alloc_size(). */ void devm_mdiobus_free(struct device *dev, struct mii_bus *bus) { int rc; rc = devres_release(dev, _devm_mdiobus_free, devm_mdiobus_match, bus); WARN_ON(rc); } EXPORT_SYMBOL_GPL(devm_mdiobus_free); /** * 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); } static struct class mdio_bus_class = { .name = "mdio_bus", .dev_release = mdiobus_release, }; #if IS_ENABLED(CONFIG_OF_MDIO) /* Helper function for of_mdio_find_bus */ static int of_mdio_bus_match(struct device *dev, const void *mdio_bus_np) { return dev->of_node == mdio_bus_np; } /** * 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(&mdio_bus_class, NULL, mdio_bus_np, of_mdio_bus_match); 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 * phy's address with its 'reg' property. If found, set the of_node pointer for * the phy. This allows auto-probed pyh devices to be supplied with information * passed in via DT. */ static void of_mdiobus_link_phydev(struct mii_bus *mdio, struct phy_device *phydev) { struct device *dev = &phydev->dev; struct device_node *child; if (dev->of_node || !mdio->dev.of_node) return; for_each_available_child_of_node(mdio->dev.of_node, child) { int addr; int ret; ret = of_property_read_u32(child, "reg", &addr); if (ret < 0) { dev_err(dev, "%s has invalid PHY address\n", child->full_name); continue; } /* A PHY must have a reg property in the range [0-31] */ if (addr >= PHY_MAX_ADDR) { dev_err(dev, "%s PHY address %i is too large\n", child->full_name, addr); continue; } if (addr == phydev->addr) { dev->of_node = child; return; } } } #else /* !IS_ENABLED(CONFIG_OF_MDIO) */ static inline void of_mdiobus_link_phydev(struct mii_bus *mdio, struct phy_device *phydev) { } #endif /** * __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. * * Returns 0 on success or < 0 on error. */ int __mdiobus_register(struct mii_bus *bus, struct module *owner) { int i, err; 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); if (bus->reset) bus->reset(bus); 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)) { err = PTR_ERR(phydev); goto error; } } } bus->state = MDIOBUS_REGISTERED; pr_info("%s: probed\n", bus->name); return 0; error: while (--i >= 0) { struct phy_device *phydev = bus->phy_map[i]; if (phydev) { phy_device_remove(phydev); phy_device_free(phydev); } } device_del(&bus->dev); return err; } EXPORT_SYMBOL(__mdiobus_register); void mdiobus_unregister(struct mii_bus *bus) { int i; if (WARN_ON_ONCE(bus->state != MDIOBUS_REGISTERED)) return; bus->state = MDIOBUS_UNREGISTERED; for (i = 0; i < PHY_MAX_ADDR; i++) { struct phy_device *phydev = bus->phy_map[i]; if (phydev) { phy_device_remove(phydev); phy_device_free(phydev); } } 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); struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr) { struct phy_device *phydev; int err; phydev = get_phy_device(bus, addr, false); if (IS_ERR(phydev) || phydev == NULL) 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_phydev(bus, phydev); err = phy_device_register(phydev); if (err) { phy_device_free(phydev); return NULL; } return phydev; } EXPORT_SYMBOL(mdiobus_scan); /** * 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; BUG_ON(in_interrupt()); mutex_lock_nested(&bus->mdio_lock, SINGLE_DEPTH_NESTING); retval = bus->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; BUG_ON(in_interrupt()); mutex_lock(&bus->mdio_lock); retval = bus->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; BUG_ON(in_interrupt()); mutex_lock_nested(&bus->mdio_lock, SINGLE_DEPTH_NESTING); err = bus->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; BUG_ON(in_interrupt()); mutex_lock(&bus->mdio_lock); err = bus->write(bus, addr, regnum, val); mutex_unlock(&bus->mdio_lock); return err; } EXPORT_SYMBOL(mdiobus_write); /** * mdio_bus_match - determine if given PHY driver supports the given PHY device * @dev: target PHY device * @drv: given PHY driver * * Description: Given a PHY device, and a PHY driver, return 1 if * the driver supports the device. Otherwise, return 0. */ static int mdio_bus_match(struct device *dev, struct device_driver *drv) { struct phy_device *phydev = to_phy_device(dev); struct phy_driver *phydrv = to_phy_driver(drv); const int num_ids = ARRAY_SIZE(phydev->c45_ids.device_ids); int i; if (of_driver_match_device(dev, drv)) return 1; if (phydrv->match_phy_device) return phydrv->match_phy_device(phydev); if (phydev->is_c45) { for (i = 1; i < num_ids; i++) { if (!(phydev->c45_ids.devices_in_package & (1 << i))) continue; if ((phydrv->phy_id & phydrv->phy_id_mask) == (phydev->c45_ids.device_ids[i] & phydrv->phy_id_mask)) return 1; } return 0; } else { return (phydrv->phy_id & phydrv->phy_id_mask) == (phydev->phy_id & phydrv->phy_id_mask); } } #ifdef CONFIG_PM static bool mdio_bus_phy_may_suspend(struct phy_device *phydev) { struct device_driver *drv = phydev->dev.driver; struct phy_driver *phydrv = to_phy_driver(drv); struct net_device *netdev = phydev->attached_dev; if (!drv || !phydrv->suspend) return false; /* PHY not attached? May suspend if the PHY has not already been * suspended as part of a prior call to phy_disconnect() -> * phy_detach() -> phy_suspend() because the parent netdev might be the * MDIO bus driver and clock gated at this point. */ if (!netdev) return !phydev->suspended; /* Don't suspend PHY if the attched netdev parent may wakeup. * The parent may point to a PCI device, as in tg3 driver. */ if (netdev->dev.parent && device_may_wakeup(netdev->dev.parent)) return false; /* Also don't suspend PHY if the netdev itself may wakeup. This * is the case for devices w/o underlaying pwr. mgmt. aware bus, * e.g. SoC devices. */ if (device_may_wakeup(&netdev->dev)) return false; return true; } static int mdio_bus_suspend(struct device *dev) { struct phy_device *phydev = to_phy_device(dev); /* We must stop the state machine manually, otherwise it stops out of * control, possibly with the phydev->lock held. Upon resume, netdev * may call phy routines that try to grab the same lock, and that may * lead to a deadlock. */ if (phydev->attached_dev && phydev->adjust_link) phy_stop_machine(phydev); if (!mdio_bus_phy_may_suspend(phydev)) return 0; return phy_suspend(phydev); } static int mdio_bus_resume(struct device *dev) { struct phy_device *phydev = to_phy_device(dev); int ret; if (!mdio_bus_phy_may_suspend(phydev)) goto no_resume; ret = phy_resume(phydev); if (ret < 0) return ret; no_resume: if (phydev->attached_dev && phydev->adjust_link) phy_start_machine(phydev); return 0; } static int mdio_bus_restore(struct device *dev) { struct phy_device *phydev = to_phy_device(dev); struct net_device *netdev = phydev->attached_dev; int ret; if (!netdev) return 0; ret = phy_init_hw(phydev); if (ret < 0) return ret; /* The PHY needs to renegotiate. */ phydev->link = 0; phydev->state = PHY_UP; phy_start_machine(phydev); return 0; } static const struct dev_pm_ops mdio_bus_pm_ops = { .suspend = mdio_bus_suspend, .resume = mdio_bus_resume, .freeze = mdio_bus_suspend, .thaw = mdio_bus_resume, .restore = mdio_bus_restore, }; #define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops) #else #define MDIO_BUS_PM_OPS NULL #endif /* CONFIG_PM */ static ssize_t phy_id_show(struct device *dev, struct device_attribute *attr, char *buf) { struct phy_device *phydev = to_phy_device(dev); return sprintf(buf, "0x%.8lx\n", (unsigned long)phydev->phy_id); } static DEVICE_ATTR_RO(phy_id); static ssize_t phy_interface_show(struct device *dev, struct device_attribute *attr, char *buf) { struct phy_device *phydev = to_phy_device(dev); const char *mode = NULL; if (phy_is_internal(phydev)) mode = "internal"; else mode = phy_modes(phydev->interface); return sprintf(buf, "%s\n", mode); } static DEVICE_ATTR_RO(phy_interface); static ssize_t phy_has_fixups_show(struct device *dev, struct device_attribute *attr, char *buf) { struct phy_device *phydev = to_phy_device(dev); return sprintf(buf, "%d\n", phydev->has_fixups); } static DEVICE_ATTR_RO(phy_has_fixups); static struct attribute *mdio_dev_attrs[] = { &dev_attr_phy_id.attr, &dev_attr_phy_interface.attr, &dev_attr_phy_has_fixups.attr, NULL, }; ATTRIBUTE_GROUPS(mdio_dev); struct bus_type mdio_bus_type = { .name = "mdio_bus", .match = mdio_bus_match, .pm = MDIO_BUS_PM_OPS, .dev_groups = mdio_dev_groups, }; 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; } void mdio_bus_exit(void) { class_unregister(&mdio_bus_class); bus_unregister(&mdio_bus_type); }