phy.c

// SPDX-License-Identifier: GPL-2.0+
/* Framework for configuring and reading PHY devices
 * Based on code in sungem_phy.c and gianfar_phy.c
 *
 * Author: Andy Fleming
 *
 * Copyright (c) 2004 Freescale Semiconductor, Inc.
 * Copyright (c) 2006, 2007  Maciej W. Rozycki
 */

#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/netlink.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 <linux/phy_led_triggers.h>
#include <linux/sfp.h>
#include <linux/workqueue.h>
#include <linux/mdio.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#include <linux/atomic.h>

#define PHY_STATE_TIME	HZ

#define PHY_STATE_STR(_state)			\
	case PHY_##_state:			\
		return __stringify(_state);	\

static const char *phy_state_to_str(enum phy_state st)
{
	switch (st) {
	PHY_STATE_STR(DOWN)
	PHY_STATE_STR(READY)
	PHY_STATE_STR(UP)
	PHY_STATE_STR(RUNNING)
	PHY_STATE_STR(NOLINK)
	PHY_STATE_STR(CABLETEST)
	PHY_STATE_STR(HALTED)
	}

	return NULL;
}

static void phy_link_up(struct phy_device *phydev)
{
	phydev->phy_link_change(phydev, true, true);
	phy_led_trigger_change_speed(phydev);
}

static void phy_link_down(struct phy_device *phydev, bool do_carrier)
{
	phydev->phy_link_change(phydev, false, do_carrier);
	phy_led_trigger_change_speed(phydev);
}

static const char *phy_pause_str(struct phy_device *phydev)
{
	bool local_pause, local_asym_pause;

	if (phydev->autoneg == AUTONEG_DISABLE)
		goto no_pause;

	local_pause = linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT,
					phydev->advertising);
	local_asym_pause = linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
					     phydev->advertising);

	if (local_pause && phydev->pause)
		return "rx/tx";

	if (local_asym_pause && phydev->asym_pause) {
		if (local_pause)
			return "rx";
		if (phydev->pause)
			return "tx";
	}

no_pause:
	return "off";
}

/**
 * phy_print_status - Convenience function to print out the current phy status
 * @phydev: the phy_device struct
 */
void phy_print_status(struct phy_device *phydev)
{
	if (phydev->link) {
		netdev_info(phydev->attached_dev,
			"Link is Up - %s/%s %s- flow control %s\n",
			phy_speed_to_str(phydev->speed),
			phy_duplex_to_str(phydev->duplex),
			phydev->downshifted_rate ? "(downshifted) " : "",
			phy_pause_str(phydev));
	} else	{
		netdev_info(phydev->attached_dev, "Link is Down\n");
	}
}
EXPORT_SYMBOL(phy_print_status);

/**
 * phy_clear_interrupt - Ack the phy device's interrupt
 * @phydev: the phy_device struct
 *
 * If the @phydev driver has an ack_interrupt function, call it to
 * ack and clear the phy device's interrupt.
 *
 * Returns 0 on success or < 0 on error.
 */
static int phy_clear_interrupt(struct phy_device *phydev)
{
	if (phydev->drv->ack_interrupt)
		return phydev->drv->ack_interrupt(phydev);

	return 0;
}

/**
 * phy_config_interrupt - configure the PHY device for the requested interrupts
 * @phydev: the phy_device struct
 * @interrupts: interrupt flags to configure for this @phydev
 *
 * Returns 0 on success or < 0 on error.
 */
static int phy_config_interrupt(struct phy_device *phydev, bool interrupts)
{
	phydev->interrupts = interrupts ? 1 : 0;
	if (phydev->drv->config_intr)
		return phydev->drv->config_intr(phydev);

	return 0;
}

/**
 * phy_restart_aneg - restart auto-negotiation
 * @phydev: target phy_device struct
 *
 * Restart the autonegotiation on @phydev.  Returns >= 0 on success or
 * negative errno on error.
 */
int phy_restart_aneg(struct phy_device *phydev)
{
	int ret;

	if (phydev->is_c45 && !(phydev->c45_ids.devices_in_package & BIT(0)))
		ret = genphy_c45_restart_aneg(phydev);
	else
		ret = genphy_restart_aneg(phydev);

	return ret;
}
EXPORT_SYMBOL_GPL(phy_restart_aneg);

/**
 * phy_aneg_done - return auto-negotiation status
 * @phydev: target phy_device struct
 *
 * Description: Return the auto-negotiation status from this @phydev
 * Returns > 0 on success or < 0 on error. 0 means that auto-negotiation
 * is still pending.
 */
int phy_aneg_done(struct phy_device *phydev)
{
	if (phydev->drv && phydev->drv->aneg_done)
		return phydev->drv->aneg_done(phydev);
	else if (phydev->is_c45)
		return genphy_c45_aneg_done(phydev);
	else
		return genphy_aneg_done(phydev);
}
EXPORT_SYMBOL(phy_aneg_done);

/**
 * phy_find_valid - find a PHY setting that matches the requested parameters
 * @speed: desired speed
 * @duplex: desired duplex
 * @supported: mask of supported link modes
 *
 * Locate a supported phy setting that is, in priority order:
 * - an exact match for the specified speed and duplex mode
 * - a match for the specified speed, or slower speed
 * - the slowest supported speed
 * Returns the matched phy_setting entry, or %NULL if no supported phy
 * settings were found.
 */
static const struct phy_setting *
phy_find_valid(int speed, int duplex, unsigned long *supported)
{
	return phy_lookup_setting(speed, duplex, supported, false);