phy_device.c

linux-2.6.15.6

/*
 * 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/config.h>
#include <linux/kernel.h>
#include <linux/sched.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/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>

MODULE_DESCRIPTION("PHY library");
MODULE_AUTHOR("Andy Fleming");
MODULE_LICENSE("GPL");

static struct phy_driver genphy_driver;
extern int mdio_bus_init(void);
extern void mdio_bus_exit(void);

/* get_phy_device
 *
 * 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)
{
	int phy_reg;
	u32 phy_id;
	struct phy_device *dev = NULL;

	/* 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 ERR_PTR(phy_reg);

	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 ERR_PTR(phy_reg);

	phy_id |= (phy_reg & 0xffff);

	/* If the phy_id is all Fs, there is no device there */
	if (0xffffffff == phy_id)
		return NULL;

	/* Otherwise, we allocate the device, and initialize the
	 * default values */
	dev = kcalloc(1, sizeof(*dev), GFP_KERNEL);

	if (NULL == dev)
		return ERR_PTR(-ENOMEM);

	dev->speed = 0;
	dev->duplex = -1;
	dev->pause = dev->asym_pause = 0;
	dev->link = 1;

	dev->autoneg = AUTONEG_ENABLE;

	dev->addr = addr;
	dev->phy_id = phy_id;
	dev->bus = bus;

	dev->state = PHY_DOWN;

	spin_lock_init(&dev->lock);

	return dev;
}

/* phy_prepare_link:
 *
 * 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:
 *
 * 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 *phy_id,
		void (*handler)(struct net_device *), u32 flags)
{
	struct phy_device *phydev;

	phydev = phy_attach(dev, phy_id, flags);

	if (IS_ERR(phydev))
		return phydev;

	phy_prepare_link(phydev, handler);

	phy_start_machine(phydev, NULL);

	if (phydev->irq > 0)
		phy_start_interrupts(phydev);

	return phydev;
}
EXPORT_SYMBOL(phy_connect);

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:
 *
 *   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.
 */
static int phy_compare_id(struct device *dev, void *data)
{
	return strcmp((char *)data, dev->bus_id) ? 0 : 1;
}

struct phy_device *phy_attach(struct net_device *dev,
		const char *phy_id, u32 flags)
{
	struct bus_type *bus = &mdio_bus_type;
	struct phy_device *phydev;
	struct device *d;

	/* Search the list of PHY devices on the mdio bus for the
	 * PHY with the requested name */
	d = bus_find_device(bus, NULL, (void *)phy_id, phy_compare_id);

	if (d) {
		phydev = to_phy_device(d);
	} else {
		printk(KERN_ERR "%s not found\n", phy_id);
		return ERR_PTR(-ENODEV);
	}

	/* 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;
		down_write(&d->bus->subsys.rwsem);
		d->driver = &genphy_driver.driver;

		err = d->driver->probe(d);

		if (err < 0)
			return ERR_PTR(err);

		device_bind_driver(d);
		up_write(&d->bus->subsys.rwsem);
	}

	if (phydev->attached_dev) {
		printk(KERN_ERR "%s: %s already attached\n",
				dev->name, phy_id);
		return ERR_PTR(-EBUSY);
	}

	phydev->attached_dev = dev;

	phydev->dev_flags = flags;

	return phydev;
}
EXPORT_SYMBOL(phy_attach);

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) {
		down_write(&phydev->dev.bus->subsys.rwsem);
		device_release_driver(&phydev->dev);
		up_write(&phydev->dev.bus->subsys.rwsem);
	}
}
EXPORT_SYMBOL(phy_detach);


/* Generic PHY support and helper functions */

/* genphy_config_advert
 *
 * description: Writes MII_ADVERTISE with the appropriate values,
 *   after sanitizing the values to make sure we only advertise
 *   what is supported
 */
int genphy_config_advert(struct phy_device *phydev)
{
	u32 advertise;
	int adv;
	int err;

	/* Only allow advertising what
	 * this PHY supports */
	phydev->advertising &= phydev->supported;
	advertise = phydev->advertising;

	/* Setup standard advertisement */
	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;

	err = phy_write(phydev, MII_ADVERTISE, adv);

	if (err < 0)
		return err;

	/* Configure gigabit if it's supported */
	if (phydev->supported & (SUPPORTED_1000baseT_Half |
				SUPPORTED_1000baseT_Full)) {
		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;
		err = phy_write(phydev, MII_CTRL1000, adv);

		if (err < 0)
			return err;
	}

	return adv;
}
EXPORT_SYMBOL(genphy_config_advert);

/* genphy_setup_forced
 *
 * 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 ctl = BMCR_RESET;

	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;
	
	ctl = phy_write(phydev, MII_BMCR, ctl);

	if (ctl < 0)
		return ctl;

	/* We just reset the device, so we'd better configure any
	 * settings the PHY requires to operate */
	if (phydev->drv->config_init)
		ctl = phydev->drv->config_init(phydev);

	return ctl;
}


/* Enable and Restart Autonegotiation */
int genphy_restart_aneg(struct phy_device *phydev)
{
	int ctl;