/*      $OpenBSD: aps.c,v 1.19 2009/05/24 16:40:18 jsg Exp $    */
/*
 * Copyright (c) 2005 Jonathan Gray <jsg@openbsd.org>
 * Copyright (c) 2008 Can Erkin Acar <canacar@openbsd.org>
 * Copyright (c) 2010 Constantine A. Murenin <cnst++@dragonflybsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * A driver for the ThinkPad Active Protection System based on notes from
 * http://www.almaden.ibm.com/cs/people/marksmith/tpaps.html
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <sys/sensors.h>

#include <bus/isa/isavar.h>

#if defined(APSDEBUG)
#define DPRINTF(x)              do { kprintf x; } while (0)
#else
#define DPRINTF(x)
#endif


/*
 * EC interface on Thinkpad Laptops, from Linux HDAPS driver notes.
 * From Renesans H8S/2140B Group Hardware Manual
 * http://documentation.renesas.com/eng/products/mpumcu/rej09b0300_2140bhm.pdf
 *
 * EC uses LPC Channel 3 registers TWR0..15
 */

/* STR3 status register */
#define APS_STR3                0x04

#define APS_STR3_IBF3B  0x80    /* Input buffer full (host->slave) */
#define APS_STR3_OBF3B  0x40    /* Output buffer full (slave->host)*/
#define APS_STR3_MWMF   0x20    /* Master write mode */
#define APS_STR3_SWMF   0x10    /* Slave write mode */


/* Base address of TWR registers */
#define APS_TWR_BASE            0x10
#define APS_TWR_RET             0x1f

/* TWR registers */
#define APS_CMD                 0x00
#define APS_ARG1                0x01
#define APS_ARG2                0x02
#define APS_ARG3                0x03
#define APS_RET                 0x0f

/* Sensor values */
#define APS_STATE               0x01
#define APS_XACCEL              0x02
#define APS_YACCEL              0x04
#define APS_TEMP                0x06
#define APS_XVAR                0x07
#define APS_YVAR                0x09
#define APS_TEMP2               0x0b
#define APS_UNKNOWN             0x0c
#define APS_INPUT               0x0d

/* write masks for I/O, send command + 0-3 arguments*/
#define APS_WRITE_0             0x0001
#define APS_WRITE_1             0x0003
#define APS_WRITE_2             0x0007
#define APS_WRITE_3             0x000f

/* read masks for I/O, read 0-3 values (skip command byte) */
#define APS_READ_0              0x0000
#define APS_READ_1              0x0002
#define APS_READ_2              0x0006
#define APS_READ_3              0x000e

#define APS_READ_RET            0x8000
#define APS_READ_ALL            0xffff

/* Bit definitions for APS_INPUT value */
#define APS_INPUT_KB            (1 << 5)
#define APS_INPUT_MS            (1 << 6)
#define APS_INPUT_LIDOPEN       (1 << 7)

#define APS_ADDR_BASE           0x1600
#define APS_ADDR_SIZE           0x1f

struct aps_sensor_rec {
        u_int8_t        state;
        u_int16_t       x_accel;
        u_int16_t       y_accel;
        u_int8_t        temp1;
        u_int16_t       x_var;
        u_int16_t       y_var;
        u_int8_t        temp2;
        u_int8_t        unk;
        u_int8_t        input;
};

#define APS_NUM_SENSORS         9

#define APS_SENSOR_XACCEL       0
#define APS_SENSOR_YACCEL       1
#define APS_SENSOR_XVAR         2
#define APS_SENSOR_YVAR         3
#define APS_SENSOR_TEMP1        4
#define APS_SENSOR_TEMP2        5
#define APS_SENSOR_KBACT        6
#define APS_SENSOR_MSACT        7
#define APS_SENSOR_LIDOPEN      8

struct aps_softc {
        device_t                sc_dev;

        struct resource         *sc_iores;
        int                     sc_iorid;

        struct ksensor          sensors[APS_NUM_SENSORS];
        struct ksensordev       sensordev;

        struct aps_sensor_rec   aps_data;
};

static void     aps_identify(driver_t *, device_t);
static int      aps_probe(device_t);
static int      aps_attach(device_t);
static int      aps_detach(device_t);

static int      aps_resume(device_t);
static int      aps_suspend(device_t);

static int      aps_init(struct resource *);
static int      aps_read_data(struct aps_softc *);
static void     aps_refresh_sensor_data(struct aps_softc *);
static void     aps_refresh(void *);
static int      aps_do_io(struct resource *, unsigned char *, int, int);

static device_method_t aps_methods[] = {
        DEVMETHOD(device_identify,      aps_identify),
        DEVMETHOD(device_probe,         aps_probe),
        DEVMETHOD(device_attach,        aps_attach),
        DEVMETHOD(device_detach,        aps_detach),

        DEVMETHOD(device_resume,        aps_resume),
        DEVMETHOD(device_suspend,       aps_suspend),
        { NULL, NULL }
};

static driver_t aps_driver = {
        "aps",
        aps_methods,
        sizeof(struct aps_softc)
};

static devclass_t aps_devclass;

DRIVER_MODULE(aps, isa, aps_driver, aps_devclass, NULL, NULL);



/* properly communicate with the controller, writing a set of memory
 * locations and reading back another set  */
static int
aps_do_io(struct resource *iores, unsigned char *buf, int wmask, int rmask)
{
        bus_space_tag_t iot = rman_get_bustag(iores);
        bus_space_handle_t ioh = rman_get_bushandle(iores);
        int bp, stat, n;

        DPRINTF(("aps_do_io: CMD: 0x%02x, wmask: 0x%04x, rmask: 0x%04x\n",
               buf[0], wmask, rmask));

        /* write init byte using arbitration */
        for (n = 0; n < 100; n++) {
                stat = bus_space_read_1(iot, ioh, APS_STR3);
                if (stat & (APS_STR3_OBF3B | APS_STR3_SWMF)) {
                        bus_space_read_1(iot, ioh, APS_TWR_RET);
                        continue;
                }
                bus_space_write_1(iot, ioh, APS_TWR_BASE, buf[0]);
                stat = bus_space_read_1(iot, ioh, APS_STR3);
                if (stat & (APS_STR3_MWMF))
                        break;
                DRIVERSLEEP(1);
        }

        if (n == 100) {
                DPRINTF(("aps_do_io: Failed to get bus\n"));
                return (1);
        }

        /* write data bytes, init already sent */
        /* make sure last bye is always written as this will trigger slave */
        wmask |= APS_READ_RET;
        buf[APS_RET] = 0x01;

        for (n = 1, bp = 2; n < 16; bp <<= 1, n++) {
                if (wmask & bp) {
                        bus_space_write_1(iot, ioh, APS_TWR_BASE + n, buf[n]);
                        DPRINTF(("aps_do_io:  write %2d 0x%02x\n", n, buf[n]));
                }
        }

        for (n = 0; n < 100; n++) {
                stat = bus_space_read_1(iot, ioh, APS_STR3);
                if (stat & (APS_STR3_OBF3B))
                        break;
                DRIVERSLEEP(500);
        }

        if (n == 100) {
                DPRINTF(("aps_do_io: timeout waiting response\n"));
                return (1);
        }
        /* wait for data available */
        /* make sure to read the final byte to clear status */
        rmask |= APS_READ_RET;

        /* read cmd and data bytes */
        for (n = 0, bp = 1; n < 16; bp <<= 1, n++) {
                if (rmask & bp) {
                        buf[n] = bus_space_read_1(iot, ioh, APS_TWR_BASE + n);
                        DPRINTF(("aps_do_io:  read %2d 0x%02x\n", n, buf[n]));
                }
        }

        return (0);
}

/* for hints, see /sys/bus/isa/isahint.c */

static void
aps_identify(driver_t *driver, device_t parent)
{
        device_t child;

        child = device_find_child(parent, driver->name, -1);
        if (child != NULL) {
                if (isa_get_portsize(child) == 0) {
                        // aps(4) must have been compiled into the kernel
                        if (bootverbose)
                                kprintf("%s: will specify the port\n",
                                    __func__);
                } else if (isa_get_port(child) != APS_ADDR_BASE)
                        kprintf("%s: will overwrite specified port\n",
                            __func__);
                else {
                        if (isa_get_portsize(child) == APS_ADDR_SIZE) {
                                // aps.ko must have been reloaded
                                kprintf("%s: already have been invoked\n",
                                    __func__);
                                return;
                        } else
                                kprintf("%s: will amend the portsize\n",
                                    __func__);
                }
        } else {
                // first invocation of `kldload aps.ko`
                kprintf("%s: creating a new %s\n",
                    __func__, driver->name);
                child = BUS_ADD_CHILD(parent, parent, ISA_ORDER_PNP,
                    driver->name, -1);
                if (child == NULL) {
                        kprintf("%s: cannot add child\n", __func__);
                        return;
                }
        }
        if (bus_set_resource(child, SYS_RES_IOPORT, 0,
                APS_ADDR_BASE, APS_ADDR_SIZE, -1))
                kprintf("%s: cannot set resource\n", __func__);
}

static int
aps_probe(device_t dev)
{
        struct resource *iores;
        int iorid = 0;
        u_int8_t cr;
        unsigned char iobuf[16];

#if defined(APSDEBUG) || defined(KLD_MODULE)
        device_printf(dev, "%s: port 0x%x\n", __func__, isa_get_port(dev));
#endif

        if (device_get_unit(dev) != 0)
                return ENXIO;

        iores = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &iorid, RF_ACTIVE);
        if (iores == NULL) {
                DPRINTF(("aps: can't map i/o space\n"));
                return ENXIO;
        }


        /* See if this machine has APS */

        /* get APS mode */
        iobuf[APS_CMD] = 0x13;
        if (aps_do_io(iores, iobuf, APS_WRITE_0, APS_READ_1)) {
                bus_release_resource(dev, SYS_RES_IOPORT, iorid, iores);
                return ENXIO;
        }

        /*
         * Observed values from Linux driver:
         * 0x01: T42
         * 0x02: chip already initialised
         * 0x03: T41
         * 0x05: T61
         */

        cr = iobuf[APS_ARG1];

        bus_release_resource(dev, SYS_RES_IOPORT, iorid, iores);
        DPRINTF(("aps: state register 0x%x\n", cr));

        if (iobuf[APS_RET] != 0 || cr < 1 || cr > 5) {
                DPRINTF(("aps: unsupported state %d\n", cr));
                return ENXIO;
        }
        device_set_desc(dev, "ThinkPad Active Protection System");
        return 0;
}

static int
aps_attach(device_t dev)
{
        struct aps_softc *sc = device_get_softc(dev);

        sc->sc_dev = dev;
        sc->sc_iores = bus_alloc_resource_any(dev, SYS_RES_IOPORT,
            &sc->sc_iorid, RF_ACTIVE);
        if (sc->sc_iores == NULL) {
                device_printf(dev, "can't map i/o space\n");
                return ENXIO;
        }

        if (aps_init(sc->sc_iores)) {
                device_printf(dev, "failed to initialise\n");
                bus_release_resource(dev, SYS_RES_IOPORT, sc->sc_iorid, sc->sc_iores);
                return ENXIO;
        }

        sc->sensors[APS_SENSOR_XACCEL].type = SENSOR_INTEGER;
        ksnprintf(sc->sensors[APS_SENSOR_XACCEL].desc,
            sizeof(sc->sensors[APS_SENSOR_XACCEL].desc), "X_ACCEL");

        sc->sensors[APS_SENSOR_YACCEL].type = SENSOR_INTEGER;
        ksnprintf(sc->sensors[APS_SENSOR_YACCEL].desc,
            sizeof(sc->sensors[APS_SENSOR_YACCEL].desc), "Y_ACCEL");

        sc->sensors[APS_SENSOR_TEMP1].type = SENSOR_TEMP;
        sc->sensors[APS_SENSOR_TEMP2].type = SENSOR_TEMP;

        sc->sensors[APS_SENSOR_XVAR].type = SENSOR_INTEGER;
        ksnprintf(sc->sensors[APS_SENSOR_XVAR].desc,
            sizeof(sc->sensors[APS_SENSOR_XVAR].desc), "X_VAR");

        sc->sensors[APS_SENSOR_YVAR].type = SENSOR_INTEGER;
        ksnprintf(sc->sensors[APS_SENSOR_YVAR].desc,
            sizeof(sc->sensors[APS_SENSOR_YVAR].desc), "Y_VAR");

        sc->sensors[APS_SENSOR_KBACT].type = SENSOR_INDICATOR;
        ksnprintf(sc->sensors[APS_SENSOR_KBACT].desc,
            sizeof(sc->sensors[APS_SENSOR_KBACT].desc), "Keyboard Active");

        sc->sensors[APS_SENSOR_MSACT].type = SENSOR_INDICATOR;
        ksnprintf(sc->sensors[APS_SENSOR_MSACT].desc,
            sizeof(sc->sensors[APS_SENSOR_MSACT].desc), "Mouse Active");

        sc->sensors[APS_SENSOR_LIDOPEN].type = SENSOR_INDICATOR;
        ksnprintf(sc->sensors[APS_SENSOR_LIDOPEN].desc,
            sizeof(sc->sensors[APS_SENSOR_LIDOPEN].desc), "Lid Open");

        /* stop hiding and report to the authorities */
        strlcpy(sc->sensordev.xname, device_get_nameunit(dev),
            sizeof(sc->sensordev.xname));
        for (int i = 0; i < APS_NUM_SENSORS ; i++)
                sensor_attach(&sc->sensordev, &sc->sensors[i]);

        /* Refresh sensor data every 1 second */
        /* XXX: a more frequent refresh might be appropriate */
        sensor_task_register(sc, aps_refresh, 1);

        sensordev_install(&sc->sensordev);
        return 0;
}

static int
aps_detach(device_t dev)
{
        struct aps_softc *sc = device_get_softc(dev);

        sensordev_deinstall(&sc->sensordev);
        sensor_task_unregister(sc);
        return bus_release_resource(dev, SYS_RES_IOPORT,
            sc->sc_iorid, sc->sc_iores);
}

static int
aps_init(struct resource *iores)
{
        unsigned char iobuf[16];

        /* command 0x17/0x81: check EC */
        iobuf[APS_CMD] = 0x17;
        iobuf[APS_ARG1] = 0x81;

        if (aps_do_io(iores, iobuf, APS_WRITE_1, APS_READ_3))
                return (1);

        if (iobuf[APS_RET] != 0 ||iobuf[APS_ARG3] != 0)
                return (1);

        /* Test values from the Linux driver */
        if ((iobuf[APS_ARG1] != 0 || iobuf[APS_ARG2] != 0x60) &&
            (iobuf[APS_ARG1] != 1 || iobuf[APS_ARG2] != 0))
                return (1);

        /* command 0x14: set power */
        iobuf[APS_CMD] = 0x14;
        iobuf[APS_ARG1] = 0x01;

        if (aps_do_io(iores, iobuf, APS_WRITE_1, APS_READ_0))
                return (1);

        if (iobuf[APS_RET] != 0)
                return (1);

        /* command 0x10: set config (sample rate and order) */
        iobuf[APS_CMD] = 0x10;
        iobuf[APS_ARG1] = 0xc8;
        iobuf[APS_ARG2] = 0x00;
        iobuf[APS_ARG3] = 0x02;

        if (aps_do_io(iores, iobuf, APS_WRITE_3, APS_READ_0))
                return (1);

        if (iobuf[APS_RET] != 0)
                return (1);

        /* command 0x11: refresh data */
        iobuf[APS_CMD] = 0x11;
        if (aps_do_io(iores, iobuf, APS_WRITE_0, APS_READ_1))
                return (1);
        if (iobuf[APS_ARG1] != 0)
                return (1);

        return (0);
}

static int
aps_read_data(struct aps_softc *sc)
{
        unsigned char iobuf[16];

        /* command 0x11: refresh data */
        iobuf[APS_CMD] = 0x11;
        if (aps_do_io(sc->sc_iores, iobuf, APS_WRITE_0, APS_READ_ALL))
                return (1);

        sc->aps_data.state = iobuf[APS_STATE];
        sc->aps_data.x_accel = iobuf[APS_XACCEL] + 256 * iobuf[APS_XACCEL + 1];
        sc->aps_data.y_accel = iobuf[APS_YACCEL] + 256 * iobuf[APS_YACCEL + 1];
        sc->aps_data.temp1 = iobuf[APS_TEMP];
        sc->aps_data.x_var = iobuf[APS_XVAR] + 256 * iobuf[APS_XVAR + 1];
        sc->aps_data.y_var = iobuf[APS_YVAR] + 256 * iobuf[APS_YVAR + 1];
        sc->aps_data.temp2 = iobuf[APS_TEMP2];
        sc->aps_data.input = iobuf[APS_INPUT];

        return (0);
}

static void
aps_refresh_sensor_data(struct aps_softc *sc)
{
        int64_t temp;

        if (aps_read_data(sc)) {
                for (int i = 0; i < APS_NUM_SENSORS; i++)
                        sc->sensors[i].flags |= SENSOR_FINVALID;
                return;
        }

        sc->sensors[APS_SENSOR_XACCEL].value = sc->aps_data.x_accel;
        sc->sensors[APS_SENSOR_YACCEL].value = sc->aps_data.y_accel;

        /* convert to micro (mu) degrees */
        temp = sc->aps_data.temp1 * 1000000;
        /* convert to kelvin */
        temp += 273150000;
        sc->sensors[APS_SENSOR_TEMP1].value = temp;

        /* convert to micro (mu) degrees */
        temp = sc->aps_data.temp2 * 1000000;
        /* convert to kelvin */
        temp += 273150000;
        sc->sensors[APS_SENSOR_TEMP2].value = temp;

        sc->sensors[APS_SENSOR_XVAR].value = sc->aps_data.x_var;
        sc->sensors[APS_SENSOR_YVAR].value = sc->aps_data.y_var;
        sc->sensors[APS_SENSOR_KBACT].value =
            (sc->aps_data.input &  APS_INPUT_KB) ? 1 : 0;
        sc->sensors[APS_SENSOR_MSACT].value =
            (sc->aps_data.input & APS_INPUT_MS) ? 1 : 0;
        sc->sensors[APS_SENSOR_LIDOPEN].value =
            (sc->aps_data.input & APS_INPUT_LIDOPEN) ? 1 : 0;

        for (int i = 0; i < APS_NUM_SENSORS; i++)
                sc->sensors[i].flags &= ~SENSOR_FINVALID;
}

static void
aps_refresh(void *arg)
{
        struct aps_softc *sc = (struct aps_softc *)arg;

        aps_refresh_sensor_data(sc);
}

static int
aps_resume(device_t dev)
{
        struct aps_softc *sc = device_get_softc(dev);
        unsigned char iobuf[16];

        /*
         * Redo the init sequence on resume, because APS is
         * as forgetful as it is deaf.
         */

        /* get APS mode */
        iobuf[APS_CMD] = 0x13;
        if (aps_do_io(sc->sc_iores, iobuf, APS_WRITE_0, APS_READ_1)
            || aps_init(sc->sc_iores)) {
                device_printf(sc->sc_dev, "failed to wake up\n");
                return EIO;
        }

        sensor_task_register(sc, aps_refresh, 1);
        return 0;
}

static int
aps_suspend(device_t dev)
{
        struct aps_softc *sc = device_get_softc(dev);

        for (int i = 0; i < APS_NUM_SENSORS; i++)
                sc->sensors[i].flags |= SENSOR_FINVALID;
        sensor_task_unregister(sc);
        return 0;
}