| /* |
| * drivers/net/phy/mdio_bus.c |
| * |
| * 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. |
| * |
| */ |
| #include <linux/kernel.h> |
| #include <linux/string.h> |
| #include <linux/errno.h> |
| #include <linux/unistd.h> |
| #include <linux/slab.h> |
| #include <linux/interrupt.h> |
| #include <linux/init.h> |
| #include <linux/delay.h> |
| #include <linux/device.h> |
| #include <linux/netdevice.h> |
| #include <linux/etherdevice.h> |
| #include <linux/skbuff.h> |
| #include <linux/spinlock.h> |
| #include <linux/mm.h> |
| #include <linux/module.h> |
| #include <linux/mii.h> |
| #include <linux/ethtool.h> |
| #include <linux/phy.h> |
| |
| #include <asm/io.h> |
| #include <asm/irq.h> |
| #include <asm/uaccess.h> |
| |
| /** |
| * 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); |
| |
| /** |
| * 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, 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_np: Pointer to the mii_bus. |
| * |
| * Returns a pointer to the mii_bus, or NULL if none found. |
| * |
| * 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); |
| #endif |
| |
| /** |
| * mdiobus_register - bring up all the PHYs on a given bus and attach them to bus |
| * @bus: target mii_bus |
| * |
| * Description: Called by a bus driver to bring up all the PHYs |
| * on a given bus, and attach them to the bus. |
| * |
| * Returns 0 on success or < 0 on error. |
| */ |
| int mdiobus_register(struct mii_bus *bus) |
| { |
| 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->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) { |
| printk(KERN_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) { |
| if (bus->phy_map[i]) |
| device_unregister(&bus->phy_map[i]->dev); |
| } |
| device_del(&bus->dev); |
| return err; |
| } |
| EXPORT_SYMBOL(mdiobus_register); |
| |
| void mdiobus_unregister(struct mii_bus *bus) |
| { |
| int i; |
| |
| BUG_ON(bus->state != MDIOBUS_REGISTERED); |
| bus->state = MDIOBUS_UNREGISTERED; |
| |
| device_del(&bus->dev); |
| for (i = 0; i < PHY_MAX_ADDR; i++) { |
| if (bus->phy_map[i]) |
| device_unregister(&bus->phy_map[i]->dev); |
| bus->phy_map[i] = NULL; |
| } |
| } |
| 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); |
| if (IS_ERR(phydev) || phydev == NULL) |
| return phydev; |
| |
| err = phy_device_register(phydev); |
| if (err) { |
| phy_device_free(phydev); |
| return NULL; |
| } |
| |
| return phydev; |
| } |
| EXPORT_SYMBOL(mdiobus_scan); |
| |
| /** |
| * 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 - 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); |
| |
| 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 (!netdev) |
| return true; |
| |
| /* |
| * 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_driver *phydrv = to_phy_driver(dev->driver); |
| 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 phydrv->suspend(phydev); |
| } |
| |
| static int mdio_bus_resume(struct device *dev) |
| { |
| struct phy_driver *phydrv = to_phy_driver(dev->driver); |
| struct phy_device *phydev = to_phy_device(dev); |
| int ret; |
| |
| if (!mdio_bus_phy_may_suspend(phydev)) |
| goto no_resume; |
| |
| ret = phydrv->resume(phydev); |
| if (ret < 0) |
| return ret; |
| |
| no_resume: |
| if (phydev->attached_dev && phydev->adjust_link) |
| phy_start_machine(phydev, NULL); |
| |
| 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, NULL); |
| |
| return 0; |
| } |
| |
| static 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 */ |
| |
| struct bus_type mdio_bus_type = { |
| .name = "mdio_bus", |
| .match = mdio_bus_match, |
| .pm = MDIO_BUS_PM_OPS, |
| }; |
| 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); |
| } |