/*
 * Driver for Vitesse PHYs
 *
 * Author: Kriston Carson
 *
 * Copyright (c) 2005 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/module.h>
#include <linux/mii.h>
#include <linux/ethtool.h>
#include <linux/phy.h>

/* Vitesse Extended Control Register 1 */
#define MII_VSC8244_EXT_CON1           0x17
#define MII_VSC8244_EXTCON1_INIT       0x0000
#define MII_VSC8244_EXTCON1_TX_SKEW_MASK        0x0c00
#define MII_VSC8244_EXTCON1_RX_SKEW_MASK        0x0300
#define MII_VSC8244_EXTCON1_TX_SKEW     0x0800
#define MII_VSC8244_EXTCON1_RX_SKEW     0x0200

/* Vitesse Interrupt Mask Register */
#define MII_VSC8244_IMASK               0x19
#define MII_VSC8244_IMASK_IEN           0x8000
#define MII_VSC8244_IMASK_SPEED         0x4000
#define MII_VSC8244_IMASK_LINK          0x2000
#define MII_VSC8244_IMASK_DUPLEX        0x1000
#define MII_VSC8244_IMASK_MASK          0xf000

#define MII_VSC8221_IMASK_MASK          0xa000

/* Vitesse Interrupt Status Register */
#define MII_VSC8244_ISTAT               0x1a
#define MII_VSC8244_ISTAT_STATUS        0x8000
#define MII_VSC8244_ISTAT_SPEED         0x4000
#define MII_VSC8244_ISTAT_LINK          0x2000
#define MII_VSC8244_ISTAT_DUPLEX        0x1000

/* Vitesse Auxiliary Control/Status Register */
#define MII_VSC8244_AUX_CONSTAT         0x1c
#define MII_VSC8244_AUXCONSTAT_INIT     0x0000
#define MII_VSC8244_AUXCONSTAT_DUPLEX   0x0020
#define MII_VSC8244_AUXCONSTAT_SPEED    0x0018
#define MII_VSC8244_AUXCONSTAT_GBIT     0x0010
#define MII_VSC8244_AUXCONSTAT_100      0x0008

#define MII_VSC8221_AUXCONSTAT_INIT     0x0004 /* need to set this bit? */
#define MII_VSC8221_AUXCONSTAT_RESERVED 0x0004

#define PHY_ID_VSC8244                  0x000fc6c0
#define PHY_ID_VSC8221                  0x000fc550

MODULE_DESCRIPTION("Vitesse PHY driver");
MODULE_AUTHOR("Kriston Carson");
MODULE_LICENSE("GPL");

static int vsc824x_config_init(struct phy_device *phydev)
{
        int extcon;
        int err;

        err = phy_write(phydev, MII_VSC8244_AUX_CONSTAT,
                        MII_VSC8244_AUXCONSTAT_INIT);
        if (err < 0)
                return err;

        extcon = phy_read(phydev, MII_VSC8244_EXT_CON1);

        if (extcon < 0)
                return err;

        extcon &= ~(MII_VSC8244_EXTCON1_TX_SKEW_MASK |
                        MII_VSC8244_EXTCON1_RX_SKEW_MASK);

        if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID)
                extcon |= (MII_VSC8244_EXTCON1_TX_SKEW |
                                MII_VSC8244_EXTCON1_RX_SKEW);

        err = phy_write(phydev, MII_VSC8244_EXT_CON1, extcon);

        return err;
}

static int vsc824x_ack_interrupt(struct phy_device *phydev)
{
        int err = 0;
        
        /*
         * Don't bother to ACK the interrupts if interrupts
         * are disabled.  The 824x cannot clear the interrupts
         * if they are disabled.
         */
        if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
                err = phy_read(phydev, MII_VSC8244_ISTAT);

        return (err < 0) ? err : 0;
}

static int vsc82xx_config_intr(struct phy_device *phydev)
{
        int err;

        if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
                err = phy_write(phydev, MII_VSC8244_IMASK,
                        phydev->drv->phy_id == PHY_ID_VSC8244 ?
                                MII_VSC8244_IMASK_MASK :
                                MII_VSC8221_IMASK_MASK);
        else {
                /*
                 * The Vitesse PHY cannot clear the interrupt
                 * once it has disabled them, so we clear them first
                 */
                err = phy_read(phydev, MII_VSC8244_ISTAT);

                if (err < 0)
                        return err;

                err = phy_write(phydev, MII_VSC8244_IMASK, 0);
        }

        return err;
}

/* Vitesse 824x */
static struct phy_driver vsc8244_driver = {
        .phy_id         = PHY_ID_VSC8244,
        .name           = "Vitesse VSC8244",
        .phy_id_mask    = 0x000fffc0,
        .features       = PHY_GBIT_FEATURES,
        .flags          = PHY_HAS_INTERRUPT,
        .config_init    = &vsc824x_config_init,
        .config_aneg    = &genphy_config_aneg,
        .read_status    = &genphy_read_status,
        .ack_interrupt  = &vsc824x_ack_interrupt,
        .config_intr    = &vsc82xx_config_intr,
        .driver         = { .owner = THIS_MODULE,},
};

static int vsc8221_config_init(struct phy_device *phydev)
{
        int err;

        err = phy_write(phydev, MII_VSC8244_AUX_CONSTAT,
                        MII_VSC8221_AUXCONSTAT_INIT);
        return err;

        /* Perhaps we should set EXT_CON1 based on the interface?
           Options are 802.3Z SerDes or SGMII */
}

/* Vitesse 8221 */
static struct phy_driver vsc8221_driver = {
        .phy_id         = PHY_ID_VSC8221,
        .phy_id_mask    = 0x000ffff0,
        .name           = "Vitesse VSC8221",
        .features       = PHY_GBIT_FEATURES,
        .flags          = PHY_HAS_INTERRUPT,
        .config_init    = &vsc8221_config_init,
        .config_aneg    = &genphy_config_aneg,
        .read_status    = &genphy_read_status,
        .ack_interrupt  = &vsc824x_ack_interrupt,
        .config_intr    = &vsc82xx_config_intr,
        .driver         = { .owner = THIS_MODULE,},
};

static int __init vsc82xx_init(void)
{
        int err;

        err = phy_driver_register(&vsc8244_driver);
        if (err < 0)
                return err;
        err = phy_driver_register(&vsc8221_driver);
        if (err < 0)
                phy_driver_unregister(&vsc8244_driver);
        return err;
}

static void __exit vsc82xx_exit(void)
{
        phy_driver_unregister(&vsc8244_driver);
        phy_driver_unregister(&vsc8221_driver);
}

module_init(vsc82xx_init);
module_exit(vsc82xx_exit);