/*-
 * Copyright (c) 1998, 1999, 2001 Nicolas Souchu
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * Power Management support for the Acer M15x3 chipsets
 */

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/systm.h>

#include <machine/bus.h>
#include <machine/resource.h>
#include <sys/rman.h>

#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>

#include <dev/smbus/smbconf.h>
#include "smbus_if.h"

#define ALPM_DEBUG(x)   if (alpm_debug) (x)

#ifdef DEBUG
static int alpm_debug = 1;
#else
static int alpm_debug = 0;
#endif

#define ACER_M1543_PMU_ID       0x710110b9

/*
 * I/O registers offsets - the base address is programmed via the
 * SMBBA PCI configuration register
 */
#define SMBSTS          0x0     /* SMBus host/slave status register */
#define SMBCMD          0x1     /* SMBus host/slave command register */
#define SMBSTART        0x2     /* start to generate programmed cycle */
#define SMBHADDR        0x3     /* host address register */
#define SMBHDATA        0x4     /* data A register for host controller */
#define SMBHDATB        0x5     /* data B register for host controller */
#define SMBHBLOCK       0x6     /* block register for host controller */
#define SMBHCMD         0x7     /* command register for host controller */

/* SMBHADDR mask. */
#define LSB             0x1     /* XXX: Better name: Read/Write? */

/* SMBSTS masks */
#define TERMINATE       0x80
#define BUS_COLLI       0x40
#define DEVICE_ERR      0x20
#define SMI_I_STS       0x10
#define HST_BSY         0x08
#define IDL_STS         0x04
#define HSTSLV_STS      0x02
#define HSTSLV_BSY      0x01

/* SMBCMD masks */
#define SMB_BLK_CLR     0x80
#define T_OUT_CMD       0x08
#define ABORT_HOST      0x04

/* SMBus commands */
#define SMBQUICK        0x00
#define SMBSRBYTE       0x10            /* send/receive byte */
#define SMBWRBYTE       0x20            /* write/read byte */
#define SMBWRWORD       0x30            /* write/read word */
#define SMBWRBLOCK      0x40            /* write/read block */

/* PCI configuration registers and masks
 */
#define COM             0x4
#define COM_ENABLE_IO   0x1

#define SMBBA           PCIR_BAR(1)

#define ATPC            0x5b
#define ATPC_SMBCTRL    0x04            /* XX linux has this as 0x6 */

#define SMBHSI          0xe0
#define SMBHSI_SLAVE    0x2
#define SMBHSI_HOST     0x1

#define SMBHCBC         0xe2
#define SMBHCBC_CLOCK   0x70

#define SMBCLOCK_149K   0x0
#define SMBCLOCK_74K    0x20
#define SMBCLOCK_37K    0x40
#define SMBCLOCK_223K   0x80
#define SMBCLOCK_111K   0xa0
#define SMBCLOCK_55K    0xc0

struct alpm_softc {
        int base;
        struct resource *res;
        bus_space_tag_t smbst;
        bus_space_handle_t smbsh;
        device_t smbus;
        struct mtx lock;
};

#define ALPM_LOCK(alpm)         mtx_lock(&(alpm)->lock)
#define ALPM_UNLOCK(alpm)       mtx_unlock(&(alpm)->lock)
#define ALPM_LOCK_ASSERT(alpm)  mtx_assert(&(alpm)->lock, MA_OWNED)

#define ALPM_SMBINB(alpm,register) \
        (bus_space_read_1(alpm->smbst, alpm->smbsh, register))
#define ALPM_SMBOUTB(alpm,register,value) \
        (bus_space_write_1(alpm->smbst, alpm->smbsh, register, value))

static int      alpm_detach(device_t dev);

static int
alpm_probe(device_t dev)
{

        if (pci_get_devid(dev) == ACER_M1543_PMU_ID) {
                device_set_desc(dev, "AcerLabs M15x3 Power Management Unit");

                return (BUS_PROBE_DEFAULT);
        }

        return (ENXIO);
}

static int
alpm_attach(device_t dev)
{
        int rid;
        u_int32_t l;
        struct alpm_softc *alpm;

        alpm = device_get_softc(dev);

        /* Unlock SMBIO base register access */
        l = pci_read_config(dev, ATPC, 1);
        pci_write_config(dev, ATPC, l & ~ATPC_SMBCTRL, 1);

        /*
         * XX linux sets clock to 74k, should we?
        l = pci_read_config(dev, SMBHCBC, 1);
        l &= 0x1f;
        l |= SMBCLOCK_74K;
        pci_write_config(dev, SMBHCBC, l, 1);
         */

        if (bootverbose || alpm_debug) {
                l = pci_read_config(dev, SMBHSI, 1);
                device_printf(dev, "%s/%s",
                        (l & SMBHSI_HOST) ? "host":"nohost",
                        (l & SMBHSI_SLAVE) ? "slave":"noslave");

                l = pci_read_config(dev, SMBHCBC, 1);
                switch (l & SMBHCBC_CLOCK) {
                case SMBCLOCK_149K:
                        printf(" 149K");
                        break;
                case SMBCLOCK_74K:
                        printf(" 74K");
                        break;
                case SMBCLOCK_37K:
                        printf(" 37K");
                        break;
                case SMBCLOCK_223K:
                        printf(" 223K");
                        break;
                case SMBCLOCK_111K:
                        printf(" 111K");
                        break;
                case SMBCLOCK_55K:
                        printf(" 55K");
                        break;
                default:
                        printf("unknown");
                        break;
                }
                printf("\n");
        }

        rid = SMBBA;
        alpm->res = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &rid,
            RF_ACTIVE);

        if (alpm->res == NULL) {
                device_printf(dev,"Could not allocate Bus space\n");
                return (ENXIO);
        }
        alpm->smbst = rman_get_bustag(alpm->res);
        alpm->smbsh = rman_get_bushandle(alpm->res);
        mtx_init(&alpm->lock, device_get_nameunit(dev), "alpm", MTX_DEF);

        /* attach the smbus */
        alpm->smbus = device_add_child(dev, "smbus", DEVICE_UNIT_ANY);
        if (alpm->smbus == NULL) {
                alpm_detach(dev);
                return (EINVAL);
        }
        bus_attach_children(dev);

        return (0);
}

static int
alpm_detach(device_t dev)
{
        struct alpm_softc *alpm = device_get_softc(dev);
        int error;

        error = bus_generic_detach(dev);
        if (error != 0)
                return (error);

        mtx_destroy(&alpm->lock);

        if (alpm->res)
                bus_release_resource(dev, SYS_RES_IOPORT, SMBBA, alpm->res);

        return (0);
}

static int
alpm_callback(device_t dev, int index, void *data)
{
        int error = 0;

        switch (index) {
        case SMB_REQUEST_BUS:
        case SMB_RELEASE_BUS:
                /* ok, bus allocation accepted */
                break;
        default:
                error = EINVAL;
        }

        return (error);
}

static int
alpm_clear(struct alpm_softc *sc)
{
        ALPM_SMBOUTB(sc, SMBSTS, 0xff);
        DELAY(10);

        return (0);
}

#if 0
static int
alpm_abort(struct alpm_softc *sc)
{
        ALPM_SMBOUTB(sc, SMBCMD, T_OUT_CMD | ABORT_HOST);

        return (0);
}
#endif

static int
alpm_idle(struct alpm_softc *sc)
{
        u_char sts;

        sts = ALPM_SMBINB(sc, SMBSTS);

        ALPM_DEBUG(printf("alpm: idle? STS=0x%x\n", sts));

        return (sts & IDL_STS);
}

/*
 * Poll the SMBus controller
 */
static int
alpm_wait(struct alpm_softc *sc)
{
        int count = 10000;
        u_char sts = 0;
        int error;

        /* wait for command to complete and SMBus controller is idle */
        while (count--) {
                DELAY(10);
                sts = ALPM_SMBINB(sc, SMBSTS);
                if (sts & SMI_I_STS)
                        break;
        }

        ALPM_DEBUG(printf("alpm: STS=0x%x\n", sts));

        error = SMB_ENOERR;

        if (!count)
                error |= SMB_ETIMEOUT;

        if (sts & TERMINATE)
                error |= SMB_EABORT;

        if (sts & BUS_COLLI)
                error |= SMB_ENOACK;

        if (sts & DEVICE_ERR)
                error |= SMB_EBUSERR;

        if (error != SMB_ENOERR)
                alpm_clear(sc);

        return (error);
}

static int
alpm_quick(device_t dev, u_char slave, int how)
{
        struct alpm_softc *sc = (struct alpm_softc *)device_get_softc(dev);
        int error;

        ALPM_LOCK(sc);
        alpm_clear(sc);
        if (!alpm_idle(sc)) {
                ALPM_UNLOCK(sc);
                return (EBUSY);
        }

        switch (how) {
        case SMB_QWRITE:
                ALPM_DEBUG(printf("alpm: QWRITE to 0x%x", slave));
                ALPM_SMBOUTB(sc, SMBHADDR, slave & ~LSB);
                break;
        case SMB_QREAD:
                ALPM_DEBUG(printf("alpm: QREAD to 0x%x", slave));
                ALPM_SMBOUTB(sc, SMBHADDR, slave | LSB);
                break;
        default:
                panic("%s: unknown QUICK command (%x)!", __func__,
                        how);
        }
        ALPM_SMBOUTB(sc, SMBCMD, SMBQUICK);
        ALPM_SMBOUTB(sc, SMBSTART, 0xff);

        error = alpm_wait(sc);

        ALPM_DEBUG(printf(", error=0x%x\n", error));
        ALPM_UNLOCK(sc);

        return (error);
}

static int
alpm_sendb(device_t dev, u_char slave, char byte)
{
        struct alpm_softc *sc = (struct alpm_softc *)device_get_softc(dev);
        int error;

        ALPM_LOCK(sc);
        alpm_clear(sc);
        if (!alpm_idle(sc)) {
                ALPM_UNLOCK(sc);
                return (SMB_EBUSY);
        }

        ALPM_SMBOUTB(sc, SMBHADDR, slave & ~LSB);
        ALPM_SMBOUTB(sc, SMBCMD, SMBSRBYTE);
        ALPM_SMBOUTB(sc, SMBHDATA, byte);
        ALPM_SMBOUTB(sc, SMBSTART, 0xff);

        error = alpm_wait(sc);

        ALPM_DEBUG(printf("alpm: SENDB to 0x%x, byte=0x%x, error=0x%x\n", slave, byte, error));
        ALPM_UNLOCK(sc);

        return (error);
}

static int
alpm_recvb(device_t dev, u_char slave, char *byte)
{
        struct alpm_softc *sc = (struct alpm_softc *)device_get_softc(dev);
        int error;

        ALPM_LOCK(sc);
        alpm_clear(sc);
        if (!alpm_idle(sc)) {
                ALPM_UNLOCK(sc);
                return (SMB_EBUSY);
        }

        ALPM_SMBOUTB(sc, SMBHADDR, slave | LSB);
        ALPM_SMBOUTB(sc, SMBCMD, SMBSRBYTE);
        ALPM_SMBOUTB(sc, SMBSTART, 0xff);

        if ((error = alpm_wait(sc)) == SMB_ENOERR)
                *byte = ALPM_SMBINB(sc, SMBHDATA);

        ALPM_DEBUG(printf("alpm: RECVB from 0x%x, byte=0x%x, error=0x%x\n", slave, *byte, error));
        ALPM_UNLOCK(sc);

        return (error);
}

static int
alpm_writeb(device_t dev, u_char slave, char cmd, char byte)
{
        struct alpm_softc *sc = (struct alpm_softc *)device_get_softc(dev);
        int error;

        ALPM_LOCK(sc);
        alpm_clear(sc);
        if (!alpm_idle(sc)) {
                ALPM_UNLOCK(sc);
                return (SMB_EBUSY);
        }

        ALPM_SMBOUTB(sc, SMBHADDR, slave & ~LSB);
        ALPM_SMBOUTB(sc, SMBCMD, SMBWRBYTE);
        ALPM_SMBOUTB(sc, SMBHDATA, byte);
        ALPM_SMBOUTB(sc, SMBHCMD, cmd);
        ALPM_SMBOUTB(sc, SMBSTART, 0xff);

        error = alpm_wait(sc);

        ALPM_DEBUG(printf("alpm: WRITEB to 0x%x, cmd=0x%x, byte=0x%x, error=0x%x\n", slave, cmd, byte, error));
        ALPM_UNLOCK(sc);

        return (error);
}

static int
alpm_readb(device_t dev, u_char slave, char cmd, char *byte)
{
        struct alpm_softc *sc = (struct alpm_softc *)device_get_softc(dev);
        int error;

        ALPM_LOCK(sc);
        alpm_clear(sc);
        if (!alpm_idle(sc)) {
                ALPM_UNLOCK(sc);
                return (SMB_EBUSY);
        }

        ALPM_SMBOUTB(sc, SMBHADDR, slave | LSB);
        ALPM_SMBOUTB(sc, SMBCMD, SMBWRBYTE);
        ALPM_SMBOUTB(sc, SMBHCMD, cmd);
        ALPM_SMBOUTB(sc, SMBSTART, 0xff);

        if ((error = alpm_wait(sc)) == SMB_ENOERR)
                *byte = ALPM_SMBINB(sc, SMBHDATA);

        ALPM_DEBUG(printf("alpm: READB from 0x%x, cmd=0x%x, byte=0x%x, error=0x%x\n", slave, cmd, *byte, error));
        ALPM_UNLOCK(sc);

        return (error);
}

static int
alpm_writew(device_t dev, u_char slave, char cmd, short word)
{
        struct alpm_softc *sc = (struct alpm_softc *)device_get_softc(dev);
        int error;

        ALPM_LOCK(sc);
        alpm_clear(sc);
        if (!alpm_idle(sc)) {
                ALPM_UNLOCK(sc);
                return (SMB_EBUSY);
        }

        ALPM_SMBOUTB(sc, SMBHADDR, slave & ~LSB);
        ALPM_SMBOUTB(sc, SMBCMD, SMBWRWORD);
        ALPM_SMBOUTB(sc, SMBHDATA, word & 0x00ff);
        ALPM_SMBOUTB(sc, SMBHDATB, (word & 0xff00) >> 8);
        ALPM_SMBOUTB(sc, SMBHCMD, cmd);
        ALPM_SMBOUTB(sc, SMBSTART, 0xff);

        error = alpm_wait(sc);

        ALPM_DEBUG(printf("alpm: WRITEW to 0x%x, cmd=0x%x, word=0x%x, error=0x%x\n", slave, cmd, word, error));
        ALPM_UNLOCK(sc);

        return (error);
}

static int
alpm_readw(device_t dev, u_char slave, char cmd, short *word)
{
        struct alpm_softc *sc = (struct alpm_softc *)device_get_softc(dev);
        int error;
        u_char high, low;

        ALPM_LOCK(sc);
        alpm_clear(sc);
        if (!alpm_idle(sc)) {
                ALPM_UNLOCK(sc);
                return (SMB_EBUSY);
        }

        ALPM_SMBOUTB(sc, SMBHADDR, slave | LSB);
        ALPM_SMBOUTB(sc, SMBCMD, SMBWRWORD);
        ALPM_SMBOUTB(sc, SMBHCMD, cmd);
        ALPM_SMBOUTB(sc, SMBSTART, 0xff);

        if ((error = alpm_wait(sc)) == SMB_ENOERR) {
                low = ALPM_SMBINB(sc, SMBHDATA);
                high = ALPM_SMBINB(sc, SMBHDATB);

                *word = ((high & 0xff) << 8) | (low & 0xff);
        }

        ALPM_DEBUG(printf("alpm: READW from 0x%x, cmd=0x%x, word=0x%x, error=0x%x\n", slave, cmd, *word, error));
        ALPM_UNLOCK(sc);

        return (error);
}

static int
alpm_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf)
{
        struct alpm_softc *sc = (struct alpm_softc *)device_get_softc(dev);
        u_char i;
        int error;

        if (count < 1 || count > 32)
                return (SMB_EINVAL);

        ALPM_LOCK(sc);
        alpm_clear(sc);
        if(!alpm_idle(sc)) {
                ALPM_UNLOCK(sc);
                return (SMB_EBUSY);
        }

        ALPM_SMBOUTB(sc, SMBHADDR, slave & ~LSB);

        /* set the cmd and reset the
         * 32-byte long internal buffer */
        ALPM_SMBOUTB(sc, SMBCMD, SMBWRBLOCK | SMB_BLK_CLR);

        ALPM_SMBOUTB(sc, SMBHDATA, count);

        /* fill the 32-byte internal buffer */
        for (i = 0; i < count; i++) {
                ALPM_SMBOUTB(sc, SMBHBLOCK, buf[i]);
                DELAY(2);
        }
        ALPM_SMBOUTB(sc, SMBHCMD, cmd);
        ALPM_SMBOUTB(sc, SMBSTART, 0xff);

        error = alpm_wait(sc);

        ALPM_DEBUG(printf("alpm: WRITEBLK to 0x%x, count=0x%x, cmd=0x%x, error=0x%x", slave, count, cmd, error));
        ALPM_UNLOCK(sc);

        return (error);
}

static int
alpm_bread(device_t dev, u_char slave, char cmd, u_char *count, char *buf)
{
        struct alpm_softc *sc = (struct alpm_softc *)device_get_softc(dev);
        u_char data, len, i;
        int error;

        if (*count < 1 || *count > 32)
                return (SMB_EINVAL);

        ALPM_LOCK(sc);
        alpm_clear(sc);
        if (!alpm_idle(sc)) {
                ALPM_UNLOCK(sc);
                return (SMB_EBUSY);
        }

        ALPM_SMBOUTB(sc, SMBHADDR, slave | LSB);

        /* set the cmd and reset the
         * 32-byte long internal buffer */
        ALPM_SMBOUTB(sc, SMBCMD, SMBWRBLOCK | SMB_BLK_CLR);

        ALPM_SMBOUTB(sc, SMBHCMD, cmd);
        ALPM_SMBOUTB(sc, SMBSTART, 0xff);

        if ((error = alpm_wait(sc)) != SMB_ENOERR)
                        goto error;

        len = ALPM_SMBINB(sc, SMBHDATA);

        /* read the 32-byte internal buffer */
        for (i = 0; i < len; i++) {
                data = ALPM_SMBINB(sc, SMBHBLOCK);
                if (i < *count)
                        buf[i] = data;
                DELAY(2);
        }
        *count = len;

error:
        ALPM_DEBUG(printf("alpm: READBLK to 0x%x, count=0x%x, cmd=0x%x, error=0x%x", slave, *count, cmd, error));
        ALPM_UNLOCK(sc);

        return (error);
}

static device_method_t alpm_methods[] = {
        /* device interface */
        DEVMETHOD(device_probe,         alpm_probe),
        DEVMETHOD(device_attach,        alpm_attach),
        DEVMETHOD(device_detach,        alpm_detach),

        /* smbus interface */
        DEVMETHOD(smbus_callback,       alpm_callback),
        DEVMETHOD(smbus_quick,          alpm_quick),
        DEVMETHOD(smbus_sendb,          alpm_sendb),
        DEVMETHOD(smbus_recvb,          alpm_recvb),
        DEVMETHOD(smbus_writeb,         alpm_writeb),
        DEVMETHOD(smbus_readb,          alpm_readb),
        DEVMETHOD(smbus_writew,         alpm_writew),
        DEVMETHOD(smbus_readw,          alpm_readw),
        DEVMETHOD(smbus_bwrite,         alpm_bwrite),
        DEVMETHOD(smbus_bread,          alpm_bread),
        DEVMETHOD_END
};

static driver_t alpm_driver = {
        "alpm",
        alpm_methods,
        sizeof(struct alpm_softc)
};

DRIVER_MODULE(alpm, pci, alpm_driver, 0, 0);
DRIVER_MODULE(smbus, alpm, smbus_driver, 0, 0);
MODULE_DEPEND(alpm, pci, 1, 1, 1);
MODULE_DEPEND(alpm, smbus, SMBUS_MINVER, SMBUS_PREFVER, SMBUS_MAXVER);
MODULE_VERSION(alpm, 1);