text: /*
   * drivers/net/phy/phy_device.c
   *
   * Framework for finding and configuring PHYs.
   * Also contains generic PHY driver
   *
   * 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/netdevice.h>
  #include <linux/etherdevice.h>
  #include <linux/skbuff.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>
  
  MODULE_DESCRIPTION("PHY library");
  MODULE_AUTHOR("Andy Fleming");
  MODULE_LICENSE("GPL");
  
  void phy_device_free(struct phy_device *phydev)
  {
  	kfree(phydev);
  }
  EXPORT_SYMBOL(phy_device_free);
  
  static void phy_device_release(struct device *dev)
  {
  	phy_device_free(to_phy_device(dev));
  }
  
  static struct phy_driver genphy_driver;
  extern int mdio_bus_init(void);
  extern void mdio_bus_exit(void);
  
  static LIST_HEAD(phy_fixup_list);
  static DEFINE_MUTEX(phy_fixup_lock);
  
  /*
   * Creates a new phy_fixup and adds it to the list
   * @bus_id: A string which matches phydev->dev.bus_id (or PHY_ANY_ID)
   * @phy_uid: Used to match against phydev->phy_id (the UID of the PHY)
   * 	It can also be PHY_ANY_UID
   * @phy_uid_mask: Applied to phydev->phy_id and fixup->phy_uid before
   * 	comparison
   * @run: The actual code to be run when a matching PHY is found
   */
  int phy_register_fixup(const char *bus_id, u32 phy_uid, u32 phy_uid_mask,
  		int (*run)(struct phy_device *))
  {
  	struct phy_fixup *fixup;
  
  	fixup = kzalloc(sizeof(struct phy_fixup), GFP_KERNEL);
  	if (!fixup)
  		return -ENOMEM;
  
  	strlcpy(fixup->bus_id, bus_id, sizeof(fixup->bus_id));
  	fixup->phy_uid = phy_uid;
  	fixup->phy_uid_mask = phy_uid_mask;
  	fixup->run = run;
  
  	mutex_lock(&phy_fixup_lock);
  	list_add_tail(&fixup->list, &phy_fixup_list);
  	mutex_unlock(&phy_fixup_lock);
  
  	return 0;
  }
  EXPORT_SYMBOL(phy_register_fixup);
  
  /* Registers a fixup to be run on any PHY with the UID in phy_uid */
  int phy_register_fixup_for_uid(u32 phy_uid, u32 phy_uid_mask,
  		int (*run)(struct phy_device *))
  {
  	return phy_register_fixup(PHY_ANY_ID, phy_uid, phy_uid_mask, run);
  }
  EXPORT_SYMBOL(phy_register_fixup_for_uid);
  
  /* Registers a fixup to be run on the PHY with id string bus_id */
  int phy_register_fixup_for_id(const char *bus_id,
  		int (*run)(struct phy_device *))
  {
  	return phy_register_fixup(bus_id, PHY_ANY_UID, 0xffffffff, run);
  }
  EXPORT_SYMBOL(phy_register_fixup_for_id);
  
  /*
   * Returns 1 if fixup matches phydev in bus_id and phy_uid.
   * Fixups can be set to match any in one or more fields.
   */
  static int phy_needs_fixup(struct phy_device *phydev, struct phy_fixup *fixup)
  {
  	if (strcmp(fixup->bus_id, dev_name(&phydev->dev)) != 0)
  		if (strcmp(fixup->bus_id, PHY_ANY_ID) != 0)
  			return 0;
  
  	if ((fixup->phy_uid & fixup->phy_uid_mask) !=
  			(phydev->phy_id & fixup->phy_uid_mask))
  		if (fixup->phy_uid != PHY_ANY_UID)
  			return 0;
  
  	return 1;
  }
  
  /* Runs any matching fixups for this phydev */
  int phy_scan_fixups(struct phy_device *phydev)
  {
  	struct phy_fixup *fixup;
  
  	mutex_lock(&phy_fixup_lock);
  	list_for_each_entry(fixup, &phy_fixup_list, list) {
  		if (phy_needs_fixup(phydev, fixup)) {
  			int err;
  
  			err = fixup->run(phydev);
  
  			if (err < 0) {
  				mutex_unlock(&phy_fixup_lock);
  				return err;
  			}
  		}
  	}
  	mutex_unlock(&phy_fixup_lock);
  
  	return 0;
  }
  EXPORT_SYMBOL(phy_scan_fixups);
  
  struct phy_device* phy_device_create(struct mii_bus *bus, int addr, int phy_id)
  {
  	struct phy_device *dev;
  	/* We allocate the device, and initialize the
  	 * default values */
  	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
  
  	if (NULL == dev)
  		return (struct phy_device*) PTR_ERR((void*)-ENOMEM);
  
  	dev->dev.release = phy_device_release;
  
  	dev->speed = 0;
  	dev->duplex = -1;
  	dev->pause = dev->asym_pause = 0;
  	dev->link = 1;
  	dev->interface = PHY_INTERFACE_MODE_GMII;
  
  	dev->autoneg = AUTONEG_ENABLE;
  
  	dev->addr = addr;
  	dev->phy_id = phy_id;
  	dev->bus = bus;
  	dev->dev.parent = bus->parent;
  	dev->dev.bus = &mdio_bus_type;
  	dev->irq = bus->irq != NULL ? bus->irq[addr] : PHY_POLL;
  	dev_set_name(&dev->dev, PHY_ID_FMT, bus->id, addr);
  
  	dev->state = PHY_DOWN;
  
  	mutex_init(&dev->lock);
  
  	return dev;
  }
  EXPORT_SYMBOL(phy_device_create);
  
  /**
   * get_phy_id - reads the specified addr for its ID.
   * @bus: the target MII bus
   * @addr: PHY address on the MII bus
   * @phy_id: where to store the ID retrieved.
   *
   * Description: Reads the ID registers of the PHY at @addr on the
   *   @bus, stores it in @phy_id and returns zero on success.
   */
  int get_phy_id(struct mii_bus *bus, int addr, u32 *phy_id)
  {
  	int phy_reg;
  
  	/* Grab the bits from PHYIR1, and put them
  	 * in the upper half */
  	phy_reg = bus->read(bus, addr, MII_PHYSID1);
  
  	if (phy_reg < 0)
  		return -EIO;
  
  	*phy_id = (phy_reg & 0xffff) << 16;
  
  	/* Grab the bits from PHYIR2, and put them in the lower half */
  	phy_reg = bus->read(bus, addr, MII_PHYSID2);
  
  	if (phy_reg < 0)
  		return -EIO;
  
  	*phy_id |= (phy_reg & 0xffff);
  
  	return 0;
  }
  EXPORT_SYMBOL(get_phy_id);
  
  /**
   * get_phy_device - reads the specified PHY device and returns its @phy_device struct
   * @bus: the target MII bus
   * @addr: PHY address on the MII bus
   *
   * Description: Reads the ID registers of the PHY at @addr on the
   *   @bus, then allocates and returns the phy_device to represent it.
   */
  struct phy_device * get_phy_device(struct mii_bus *bus, int addr)
  {
  	struct phy_device *dev = NULL;
  	u32 phy_id;
  	int r;
  
  	r = get_phy_id(bus, addr, &phy_id);
  	if (r)
  		return ERR_PTR(r);
  
  	/* If the phy_id is mostly Fs, there is no device there */
  	if ((phy_id & 0x1fffffff) == 0x1fffffff)
  		return NULL;
  
  	dev = phy_device_create(bus, addr, phy_id);
  
  	return dev;
  }
  EXPORT_SYMBOL(get_phy_device);
  
  /**
   * phy_device_register - Register the phy device on the MDIO bus
   * @phydev: phy_device structure to be added to the MDIO bus
   */
  int phy_device_register(struct phy_device *phydev)
  {
  	int err;
  
  	/* Don't register a phy if one is already registered at this
  	 * address */
  	if (phydev->bus->phy_map[phydev->addr])
  		return -EINVAL;
  	phydev->bus->phy_map[phydev->addr] = phydev;
  
  	/* Run all of the fixups for this PHY */
  	phy_scan_fixups(phydev);
  
  	err = device_register(&phydev->dev);
  	if (err) {
  		pr_err("phy %d failed to register\n", phydev->addr);
  		goto out;
  	}
  
  	return 0;
  
   out:
  	phydev->bus->phy_map[phydev->addr] = NULL;
  	return err;
  }
  EXPORT_SYMBOL(phy_device_register);
  
  /**
   * phy_prepare_link - prepares the PHY layer to monitor link status
   * @phydev: target phy_device struct
   * @handler: callback function for link status change notifications
   *
   * Description: Tells the PHY infrastructure to handle the
   *   gory details on monitoring link status (whether through
   *   polling or an interrupt), and to call back to the
   *   connected device driver when the link status changes.
   *   If you want to monitor your own link state, don't call
   *   this function.
   */
  void phy_prepare_link(struct phy_device *phydev,
  		void (*handler)(struct net_device *))
  {
  	phydev->adjust_link = handler;
  }
  
  /**
   * phy_connect_direct - connect an ethernet device to a specific phy_device
   * @dev: the network device to connect
   * @phydev: the pointer to the phy device
   * @handler: callback function for state change notifications
   * @flags: PHY device's dev_flags
   * @interface: PHY device's interface
   */
  int phy_connect_direct(struct net_device *dev, struct phy_device *phydev,
  		       void (*handler)(struct net_device *), u32 flags,
  		       phy_interface_t interface)
  {
  	int rc;
  
  	rc = phy_attach_direct(dev, phydev, flags, interface);
  	if (rc)
  		return rc;
  
  	phy_prepare_link(phydev, handler);
  	phy_start_machine(phydev, NULL);
  	if (phydev->irq > 0)
  		phy_start_interrupts(phydev);
  
  	return 0;
  }
  EXPORT_SYMBOL(phy_connect_direct);
  
  /**
   * phy_connect - connect an ethernet device to a PHY device
   * @dev: the network device to connect
   * @bus_id: the id string of the PHY device to connect
   * @handler: callback function for state change notifications
   * @flags: PHY device's dev_flags
   * @interface: PHY device's interface
   *
   * Description: Convenience function for connecting ethernet
   *   devices to PHY devices.  The default behavior is for
   *   the PHY infrastructure to handle everything, and only notify
   *   the connected driver when the link status changes.  If you
   *   don't want, or can't use the provided functionality, you may
   *   choose to call only the subset of functions which provide
   *   the desired functionality.
   */
  struct phy_device * phy_connect(struct net_device *dev, const char *bus_id,
  		void (*handler)(struct net_device *), u32 flags,
  		phy_interface_t interface)
  {
  	struct phy_device *phydev;
  	struct device *d;
  	int rc;
  
  	/* Search the list of PHY devices on the mdio bus for the
  	 * PHY with the requested name */
  	d = bus_find_device_by_name(&mdio_bus_type, NULL, bus_id);
  	if (!d) {
  		pr_err("PHY %s not found\n", bus_id);
  		return ERR_PTR(-ENODEV);
  	}
  	phydev = to_phy_device(d);
  
  	rc = phy_connect_direct(dev, phydev, handler, flags, interface);
  	if (rc)
  		return ERR_PTR(rc);
  
  	return phydev;
  }
  EXPORT_SYMBOL(phy_connect);
  
  /**
   * phy_disconnect - disable interrupts, stop state machine, and detach a PHY device
   * @phydev: target phy_device struct
   */
  void phy_disconnect(struct phy_device *phydev)
  {
  	if (phydev->irq > 0)
  		phy_stop_interrupts(phydev);
  
  	phy_stop_machine(phydev);
  	
  	phydev->adjust_link = NULL;
  
  	phy_detach(phydev);
  }
  EXPORT_SYMBOL(phy_disconnect);
  
  /**
   * phy_attach_direct - attach a network device to a given PHY device pointer
   * @dev: network device to attach
   * @phydev: Pointer to phy_device to attach
   * @flags: PHY device's dev_flags
   * @interface: PHY device's interface
   *
   * Description: Called by drivers to attach to a particular PHY
   *     device. The phy_device is found, and properly hooked up
   *     to the phy_driver.  If no driver is attached, then the
   *     genphy_driver is used.  The phy_device is given a ptr to
   *     the attaching device, and given a callback for link status
   *     change.  The phy_device is returned to the attaching driver.
   */
  int phy_attach_direct(struct net_device *dev, struct phy_device *phydev,
  		      u32 flags, phy_interface_t interface)
  {
  	struct device *d = &phydev->dev;
  
  	/* Assume that if there is no driver, that it doesn't
  	 * exist, and we should use the genphy driver. */
  	if (NULL == d->driver) {
  		int err;
  		d->driver = &genphy_driver.driver;
  
  		err = d->driver->probe(d);
  		if (err >= 0)
  			err = device_bind_driver(d);
  
  		if (err)
  			return err;
  	}
  
  	if (phydev->attached_dev) {
  		dev_err(&dev->dev, "PHY already attached\n");
  		return -EBUSY;
  	}
  
  	phydev->attached_dev = dev;
  
  	phydev->dev_flags = flags;
  
  	phydev->interface = interface;
  
  	/* Do initial configuration here, now that
  	 * we have certain key parameters
  	 * (dev_flags and interface) */
  	if (phydev->drv->config_init) {
  		int err;
  
  		err = phy_scan_fixups(phydev);
  
  		if (err < 0)
  			return err;
  
  		err = phydev->drv->config_init(phydev);
  
  		if (err < 0)
  			return err;
  	}
  
  	return 0;
  }
  EXPORT_SYMBOL(phy_attach_direct);
  
  /**
   * phy_attach - attach a network device to a particular PHY device
   * @dev: network device to attach
   * @bus_id: Bus ID of PHY device to attach
   * @flags: PHY device's dev_flags
   * @interface: PHY device's interface
   *
   * Description: Same as phy_attach_direct() except that a PHY bus_id
   *     string is passed instead of a pointer to a struct phy_device.
   */
  struct phy_device *phy_attach(struct net_device *dev,
  		const char *bus_id, u32 flags, phy_interface_t interface)
  {
  	struct bus_type *bus = &mdio_bus_type;
  	struct phy_device *phydev;
  	struct device *d;
  	int rc;
  
  	/* Search the list of PHY devices on the mdio bus for the
  	 * PHY with the requested name */
  	d = bus_find_device_by_name(bus, NULL, bus_id);
  	if (!d) {
  		pr_err("PHY %s not found\n", bus_id);
  		return ERR_PTR(-ENODEV);
  	}
  	phydev = to_phy_device(d);
  
  	rc = phy_attach_direct(dev, phydev, flags, interface);
  	if (rc)
  		return ERR_PTR(rc);
  
  	return phydev;
  }
  EXPORT_SYMBOL(phy_attach);
  
  /**
   * phy_detach - detach a PHY device from its network device
   * @phydev: target phy_device struct
   */
  void phy_detach(struct phy_device *phydev)
  {
  	phydev->attached_dev = NULL;
  
  	/* If the device had no specific driver before (i.e. - it
  	 * was using the generic driver), we unbind the device
  	 * from the generic driver so that there's a chance a
  	 * real driver could be loaded */
  	if (phydev->dev.driver == &genphy_driver.driver)
  		device_release_driver(&phydev->dev);
  }
  EXPORT_SYMBOL(phy_detach);
  
  
  /* Generic PHY support and helper functions */
  
  /**
   * genphy_config_advert - sanitize and advertise auto-negotation parameters
   * @phydev: target phy_device struct
   *
   * Description: Writes MII_ADVERTISE with the appropriate values,
   *   after sanitizing the values to make sure we only advertise
   *   what is supported.  Returns < 0 on error, 0 if the PHY's advertisement
   *   hasn't changed, and > 0 if it has changed.
   */
  int genphy_config_advert(struct phy_device *phydev)
  {
  	u32 advertise;
  	int oldadv, adv;
  	int err, changed = 0;
  
  	/* Only allow advertising what
  	 * this PHY supports */
  	phydev->advertising &= phydev->supported;
  	advertise = phydev->advertising;
  
  	/* Setup standard advertisement */
  	oldadv = adv = phy_read(phydev, MII_ADVERTISE);
  
  	if (adv < 0)
  		return adv;
  
  	adv &= ~(ADVERTISE_ALL | ADVERTISE_100BASE4 | ADVERTISE_PAUSE_CAP | 
  		 ADVERTISE_PAUSE_ASYM);
  	if (advertise & ADVERTISED_10baseT_Half)
  		adv |= ADVERTISE_10HALF;
  	if (advertise & ADVERTISED_10baseT_Full)
  		adv |= ADVERTISE_10FULL;
  	if (advertise & ADVERTISED_100baseT_Half)
  		adv |= ADVERTISE_100HALF;
  	if (advertise & ADVERTISED_100baseT_Full)
  		adv |= ADVERTISE_100FULL;
  	if (advertise & ADVERTISED_Pause)
  		adv |= ADVERTISE_PAUSE_CAP;
  	if (advertise & ADVERTISED_Asym_Pause)
  		adv |= ADVERTISE_PAUSE_ASYM;
  
  	if (adv != oldadv) {
  		err = phy_write(phydev, MII_ADVERTISE, adv);
  
  		if (err < 0)
  			return err;
  		changed = 1;
  	}
  
  	/* Configure gigabit if it's supported */
  	if (phydev->supported & (SUPPORTED_1000baseT_Half |
  				SUPPORTED_1000baseT_Full)) {
  		oldadv = adv = phy_read(phydev, MII_CTRL1000);
  
  		if (adv < 0)
  			return adv;
  
  		adv &= ~(ADVERTISE_1000FULL | ADVERTISE_1000HALF);
  		if (advertise & SUPPORTED_1000baseT_Half)
  			adv |= ADVERTISE_1000HALF;
  		if (advertise & SUPPORTED_1000baseT_Full)
  			adv |= ADVERTISE_1000FULL;
  
  		if (adv != oldadv) {
  			err = phy_write(phydev, MII_CTRL1000, adv);
  
  			if (err < 0)
  				return err;
  			changed = 1;
  		}
  	}
  
  	return changed;
  }
  EXPORT_SYMBOL(genphy_config_advert);
  
  /**
   * genphy_setup_forced - configures/forces speed/duplex from @phydev
   * @phydev: target phy_device struct
   *
   * Description: Configures MII_BMCR to force speed/duplex
   *   to the values in phydev. Assumes that the values are valid.
   *   Please see phy_sanitize_settings().
   */
  int genphy_setup_forced(struct phy_device *phydev)
  {
  	int err;
  	int ctl = 0;
  
  	phydev->pause = phydev->asym_pause = 0;
  
  	if (SPEED_1000 == phydev->speed)
  		ctl |= BMCR_SPEED1000;
  	else if (SPEED_100 == phydev->speed)
  		ctl |= BMCR_SPEED100;
  
  	if (DUPLEX_FULL == phydev->duplex)
  		ctl |= BMCR_FULLDPLX;
  	
  	err = phy_write(phydev, MII_BMCR, ctl);
  
  	return err;
  }
  
  
  /**
   * genphy_restart_aneg - Enable and Restart Autonegotiation
   * @phydev: target phy_device struct
   */
  int genphy_restart_aneg(struct phy_device *phydev)
  {
  	int ctl;
  
  	ctl = phy_read(phydev, MII_BMCR);
  
  	if (ctl < 0)
  		return ctl;
  
  	ctl |= (BMCR_ANENABLE | BMCR_ANRESTART);
  
  	/* Don't isolate the PHY if we're negotiating */
  	ctl &= ~(BMCR_ISOLATE);
  
  	ctl = phy_write(phydev, MII_BMCR, ctl);
  
  	return ctl;
  }
  EXPORT_SYMBOL(genphy_restart_aneg);
  
  
  /**
   * genphy_config_aneg - restart auto-negotiation or write BMCR
   * @phydev: target phy_device struct
   *
   * Description: If auto-negotiation is enabled, we configure the
   *   advertising, and then restart auto-negotiation.  If it is not
   *   enabled, then we write the BMCR.
   */
  int genphy_config_aneg(struct phy_device *phydev)
  {
  	int result;
  
  	if (AUTONEG_ENABLE != phydev->autoneg)
  		return genphy_setup_forced(phydev);
  
  	result = genphy_config_advert(phydev);
  
  	if (result < 0) /* error */
  		return result;
  
  	if (result == 0) {
  		/* Advertisment hasn't changed, but maybe aneg was never on to
  		 * begin with?  Or maybe phy was isolated? */
  		int ctl = phy_read(phydev, MII_BMCR);
  
  		if (ctl < 0)
  			return ctl;
  
  		if (!(ctl & BMCR_ANENABLE) || (ctl & BMCR_ISOLATE))
  			result = 1; /* do restart aneg */
  	}
  
  	/* Only restart aneg if we are advertising something different
  	 * than we were before.	 */
  	if (result > 0)
  		result = genphy_restart_aneg(phydev);
  
  	return result;
  }
  EXPORT_SYMBOL(genphy_config_aneg);
  
  /**
   * genphy_update_link - update link status in @phydev
   * @phydev: target phy_device struct
   *
   * Description: Update the value in phydev->link to reflect the
   *   current link value.  In order to do this, we need to read
   *   the status register twice, keeping the second value.
   */
  int genphy_update_link(struct phy_device *phydev)
  {
  	int status;
  
  	/* Do a fake read */
  	status = phy_read(phydev, MII_BMSR);
  
  	if (status < 0)
  		return status;
  
  	/* Read link and autonegotiation status */
  	status = phy_read(phydev, MII_BMSR);
  
  	if (status < 0)
  		return status;
  
  	if ((status & BMSR_LSTATUS) == 0)
  		phydev->link = 0;
  	else
  		phydev->link = 1;
  
  	return 0;
  }
  EXPORT_SYMBOL(genphy_update_link);
  
  /**
   * genphy_read_status - check the link status and update current link state
   * @phydev: target phy_device struct
   *
   * Description: Check the link, then figure out the current state
   *   by comparing what we advertise with what the link partner
   *   advertises.  Start by checking the gigabit possibilities,
   *   then move on to 10/100.
   */
  int genphy_read_status(struct phy_device *phydev)
  {
  	int adv;
  	int err;
  	int lpa;
  	int lpagb = 0;
  
  	/* Update the link, but return if there
  	 * was an error */
  	err = genphy_update_link(phydev);
  	if (err)
  		return err;
  
  	if (AUTONEG_ENABLE == phydev->autoneg) {
  		if (phydev->supported & (SUPPORTED_1000baseT_Half
  					| SUPPORTED_1000baseT_Full)) {
  			lpagb = phy_read(phydev, MII_STAT1000);
  
  			if (lpagb < 0)
  				return lpagb;
  
  			adv = phy_read(phydev, MII_CTRL1000);
  
  			if (adv < 0)
  				return adv;
  
  			lpagb &= adv << 2;
  		}
  
  		lpa = phy_read(phydev, MII_LPA);
  
  		if (lpa < 0)
  			return lpa;
  
  		adv = phy_read(phydev, MII_ADVERTISE);
  
  		if (adv < 0)
  			return adv;
  
  		lpa &= adv;
  
  		phydev->speed = SPEED_10;
  		phydev->duplex = DUPLEX_HALF;
  		phydev->pause = phydev->asym_pause = 0;
  
  		if (lpagb & (LPA_1000FULL | LPA_1000HALF)) {
  			phydev->speed = SPEED_1000;
  
  			if (lpagb & LPA_1000FULL)
  				phydev->duplex = DUPLEX_FULL;
  		} else if (lpa & (LPA_100FULL | LPA_100HALF)) {
  			phydev->speed = SPEED_100;
  			
  			if (lpa & LPA_100FULL)
  				phydev->duplex = DUPLEX_FULL;
  		} else
  			if (lpa & LPA_10FULL)
  				phydev->duplex = DUPLEX_FULL;
  
  		if (phydev->duplex == DUPLEX_FULL){
  			phydev->pause = lpa & LPA_PAUSE_CAP ? 1 : 0;
  			phydev->asym_pause = lpa & LPA_PAUSE_ASYM ? 1 : 0;
  		}
  	} else {
  		int bmcr = phy_read(phydev, MII_BMCR);
  		if (bmcr < 0)
  			return bmcr;
  
  		if (bmcr & BMCR_FULLDPLX)
  			phydev->duplex = DUPLEX_FULL;
  		else
  			phydev->duplex = DUPLEX_HALF;
  
  		if (bmcr & BMCR_SPEED1000)
  			phydev->speed = SPEED_1000;
  		else if (bmcr & BMCR_SPEED100)
  			phydev->speed = SPEED_100;
  		else
  			phydev->speed = SPEED_10;
  
  		phydev->pause = phydev->asym_pause = 0;
  	}
  
  	return 0;
  }
  EXPORT_SYMBOL(genphy_read_status);
  
  static int genphy_config_init(struct phy_device *phydev)
  {
  	int val;
  	u32 features;
  
  	/* For now, I'll claim that the generic driver supports
  	 * all possible port types */
  	features = (SUPPORTED_TP | SUPPORTED_MII
  			| SUPPORTED_AUI | SUPPORTED_FIBRE |
  			SUPPORTED_BNC);
  
  	/* Do we support autonegotiation? */
  	val = phy_read(phydev, MII_BMSR);
  
  	if (val < 0)
  		return val;
  
  	if (val & BMSR_ANEGCAPABLE)
  		features |= SUPPORTED_Autoneg;
  
  	if (val & BMSR_100FULL)
  		features |= SUPPORTED_100baseT_Full;
  	if (val & BMSR_100HALF)
  		features |= SUPPORTED_100baseT_Half;
  	if (val & BMSR_10FULL)
  		features |= SUPPORTED_10baseT_Full;
  	if (val & BMSR_10HALF)
  		features |= SUPPORTED_10baseT_Half;
  
  	if (val & BMSR_ESTATEN) {
  		val = phy_read(phydev, MII_ESTATUS);
  
  		if (val < 0)
  			return val;
  
  		if (val & ESTATUS_1000_TFULL)
  			features |= SUPPORTED_1000baseT_Full;
  		if (val & ESTATUS_1000_THALF)
  			features |= SUPPORTED_1000baseT_Half;
  	}
  
  	phydev->supported = features;
  	phydev->advertising = features;
  
  	return 0;
  }
  int genphy_suspend(struct phy_device *phydev)
  {
  	int value;
  
  	mutex_lock(&phydev->lock);
  
  	value = phy_read(phydev, MII_BMCR);
  	phy_write(phydev, MII_BMCR, (value | BMCR_PDOWN));
  
  	mutex_unlock(&phydev->lock);
  
  	return 0;
  }
  EXPORT_SYMBOL(genphy_suspend);
  
  int genphy_resume(struct phy_device *phydev)
  {
  	int value;
  
  	mutex_lock(&phydev->lock);
  
  	value = phy_read(phydev, MII_BMCR);
  	phy_write(phydev, MII_BMCR, (value & ~BMCR_PDOWN));
  
  	mutex_unlock(&phydev->lock);
  
  	return 0;
  }
  EXPORT_SYMBOL(genphy_resume);
  
  int genphy_reset(struct phy_device *phydev)
  {
  	int value;
  
  	mutex_lock(&phydev->lock);
  
  	value = phy_read(phydev, MII_BMCR);
  	phy_write(phydev, MII_BMCR, (value | BMCR_RESET));
      
  	mutex_unlock(&phydev->lock);
  
  	return 0;
  }
  
  /**
   * phy_probe - probe and init a PHY device
   * @dev: device to probe and init
   *
   * Description: Take care of setting up the phy_device structure,
   *   set the state to READY (the driver's init function should
   *   set it to STARTING if needed).
   */
  static int phy_probe(struct device *dev)
  {
  	struct phy_device *phydev;
  	struct phy_driver *phydrv;
  	struct device_driver *drv;
  	int err = 0;
  
  	phydev = to_phy_device(dev);
  
  	/* Make sure the driver is held.
  	 * XXX -- Is this correct? */
  	drv = get_driver(phydev->dev.driver);
  	phydrv = to_phy_driver(drv);
  	phydev->drv = phydrv;
  
  	/* Disable the interrupt if the PHY doesn't support it */
  	if (!(phydrv->flags & PHY_HAS_INTERRUPT))
  		phydev->irq = PHY_POLL;
  
  	mutex_lock(&phydev->lock);
  
  	/* Start out supporting everything. Eventually,
  	 * a controller will attach, and may modify one
  	 * or both of these values */
  	phydev->supported = phydrv->features;
  	phydev->advertising = phydrv->features;
  
  	/* Set the state to READY by default */
  	phydev->state = PHY_READY;
  
  	if (phydev->drv->probe)
  		err = phydev->drv->probe(phydev);
  
  	mutex_unlock(&phydev->lock);
  
  	return err;
  
  }
  
  static int phy_remove(struct device *dev)
  {
  	struct phy_device *phydev;
  
  	phydev = to_phy_device(dev);
  
  	mutex_lock(&phydev->lock);
  	phydev->state = PHY_DOWN;
  	mutex_unlock(&phydev->lock);
  
  	if (phydev->drv->remove)
  		phydev->drv->remove(phydev);
  
  	put_driver(dev->driver);
  	phydev->drv = NULL;
  
  	return 0;
  }
  
  /**
   * phy_driver_register - register a phy_driver with the PHY layer
   * @new_driver: new phy_driver to register
   */
  int phy_driver_register(struct phy_driver *new_driver)
  {
  	int retval;
  
  	new_driver->driver.name = new_driver->name;
  	new_driver->driver.bus = &mdio_bus_type;
  	new_driver->driver.probe = phy_probe;
  	new_driver->driver.remove = phy_remove;
  
  	retval = driver_register(&new_driver->driver);
  
  	if (retval) {
  		printk(KERN_ERR "%s: Error %d in registering driver\n",
  				new_driver->name, retval);
  
  		return retval;
  	}
  
  	pr_debug("%s: Registered new driver\n", new_driver->name);
  
  	return 0;
  }
  EXPORT_SYMBOL(phy_driver_register);
  
  void phy_driver_unregister(struct phy_driver *drv)
  {
  	driver_unregister(&drv->driver);
  }
  EXPORT_SYMBOL(phy_driver_unregister);
  
  static struct phy_driver genphy_driver = {
  	.phy_id		= 0xffffffff,
  	.phy_id_mask	= 0xffffffff,
  	.name		= "Generic PHY",
  	.config_init	= genphy_config_init,
  	.features	= 0,
  	.config_aneg	= genphy_config_aneg,
  	.read_status	= genphy_read_status,
  	.suspend	= genphy_suspend,
  	.resume		= genphy_resume,
  	.reset      = genphy_reset,
  	.driver		= {.owner= THIS_MODULE, },
  };
  
  static int __init phy_init(void)
  {
  	int rc;
  
  	rc = mdio_bus_init();
  	if (rc)
  		return rc;
  
  	rc = phy_driver_register(&genphy_driver);
  	if (rc)
  		mdio_bus_exit();
  
  	return rc;
  }
  
  static void __exit phy_exit(void)
  {
  	phy_driver_unregister(&genphy_driver);
  	mdio_bus_exit();
  }
  
  subsys_initcall(phy_init);
  module_exit(phy_exit);
  