/* $NetBSD: asms.c,v 1.4 2021/01/27 02:29:48 thorpej Exp $ */

/*-
 * Copyright (c) 2020 Michael Lorenz
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: asms.c,v 1.4 2021/01/27 02:29:48 thorpej Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/conf.h>
#include <sys/bus.h>

#include <dev/i2c/i2cvar.h>

#include <dev/sysmon/sysmonvar.h>

struct asms_softc {
        device_t        sc_dev;
        i2c_tag_t       sc_i2c;
        i2c_addr_t      sc_addr;

        struct sysmon_envsys *sc_sme;
        envsys_data_t   sc_sensors[3];
};

static int      asms_match(device_t, cfdata_t, void *);
static void     asms_attach(device_t, device_t, void *);

static void     asms_sensors_refresh(struct sysmon_envsys *, envsys_data_t *);
static void     asms_init(struct asms_softc *);

CFATTACH_DECL_NEW(asms, sizeof(struct asms_softc),
    asms_match, asms_attach, NULL, NULL);

static const struct device_compatible_entry compat_data[] = {
        { .compat = "accelerometer" },
        { .compat = "AAPL,accelerometer_1" },
        DEVICE_COMPAT_EOL
};

/* ASMS Registers, from OpenBSD */
#define ASMS_REG_COMMAND 0x00
#define ASMS_REG_STATUS  0x01
#define ASMS_REG_RCONTROL1 0x02
#define ASMS_REG_RCONTROL2 0x03
#define ASMS_REG_RCONTROL3 0x04
#define ASMS_REG_RDATA1  0x05
#define ASMS_REG_RDATA2  0x06
#define ASMS_REG_DATA_X  0x20
#define ASMS_REG_DATA_Y  0x21
#define ASMS_REG_DATA_Z  0x22
#define ASMS_REG_SENS_LOW 0x26 /* init with 0x15 */
#define ASMS_REG_SENS_HIGH 0x27 /* init with 0x60 */
#define ASMS_REG_CONTROL_X 0x28 /* init with 0x08 */
#define ASMS_REG_CONTROL_Y 0x29 /* init with 0x0f */
#define ASMS_REG_CONTROL_Z 0x2a /* init with 0x4f */
#define ASMS_REG_UNKNOWN1 0x2b /* init with 0x14 */
#define ASMS_REG_VENDOR  0x2e
#define ASMS_CMD_READ_VER 0x01
#define ASMS_CMD_READ_MEM 0x02
#define ASMS_CMD_RESET  0x07
#define ASMS_CMD_START  0x08

static int
asms_match(device_t parent, cfdata_t match, void *aux)
{
        struct i2c_attach_args *ia = aux;
        int match_result;

        if (iic_use_direct_match(ia, match, compat_data, &match_result))
                return match_result;
        
        if ((ia->ia_addr & 0xf8) == 0xd8)
                return I2C_MATCH_ADDRESS_ONLY;

        return 0;
}

static void
asms_attach(device_t parent, device_t self, void *aux)
{
        struct asms_softc *sc = device_private(self);
        struct i2c_attach_args *ia = aux;
        envsys_data_t *s;

        sc->sc_dev = self;
        sc->sc_i2c = ia->ia_tag;
        sc->sc_addr = ia->ia_addr;

        aprint_naive("\n");
        aprint_normal(": Sudden Motion Sensor\n");

        asms_init(sc);

        sc->sc_sme = sysmon_envsys_create();
        sc->sc_sme->sme_name = device_xname(self);
        sc->sc_sme->sme_cookie = sc;
        sc->sc_sme->sme_refresh = asms_sensors_refresh;

        s = &sc->sc_sensors[0];
        s->units = ENVSYS_INTEGER;
        s->state = ENVSYS_SINVALID;
        s->private = ASMS_REG_DATA_X;
        strncpy(s->desc, "X", sizeof(s->desc));
        sysmon_envsys_sensor_attach(sc->sc_sme, s);

        s = &sc->sc_sensors[1];
        s->units = ENVSYS_INTEGER;
        s->state = ENVSYS_SINVALID;
        s->private = ASMS_REG_DATA_Y;
        strncpy(s->desc, "Y", sizeof(s->desc));
        sysmon_envsys_sensor_attach(sc->sc_sme, s);

        s = &sc->sc_sensors[2];
        s->units = ENVSYS_INTEGER;
        s->state = ENVSYS_SINVALID;
        s->private = ASMS_REG_DATA_Z;
        strncpy(s->desc, "Z", sizeof(s->desc));
        sysmon_envsys_sensor_attach(sc->sc_sme, s);

        sysmon_envsys_register(sc->sc_sme);
}

static void
asms_init(struct asms_softc *sc)
{
        int error, i, j;
        uint8_t cmd[2], data[48];

        iic_acquire_bus(sc->sc_i2c, 0);

        cmd[0] = ASMS_REG_COMMAND;
        data[0] = ASMS_CMD_START;
        error = iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, cmd, 1, data, 1, 0);
        delay(10000);

        cmd[0] = 0;
        error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, cmd, 1, data, 48, 0);
        iic_release_bus(sc->sc_i2c, 0);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "unable to read registers.\n");
                return;
        }
        for (i = 0; i < 48; i += 8) {
                printf("%02x:", i);
                for (j =0; j < 8; j++) {
                        printf(" %02x", data[i + j]);
                }
                printf("\n");
        }
}

static void
asms_sensors_refresh(struct sysmon_envsys *sme, envsys_data_t *edata)
{
        struct asms_softc *sc = sme->sme_cookie;
        uint8_t cmd = 0;
        int8_t data = 0;
        int error;

        cmd = edata->private;   
        iic_acquire_bus(sc->sc_i2c, 0);
        error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, 1, &data, 1, 0);
        iic_release_bus(sc->sc_i2c, 0);

        if (error) {
                edata->state = ENVSYS_SINVALID;
        } else {
                edata->value_cur = (int)data;
                edata->state = ENVSYS_SVALID;
        }
}