/*      $OpenBSD: asms.c,v 1.9 2023/12/26 14:04:50 miod Exp $   */
/*
 * Copyright (c) 2005 Xavier Santolaria <xsa@openbsd.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 Apple Sudden Motion Sensor based on notes from
 * https://johannes.sipsolutions.net/PowerBook/apple-motion-sensor-specification
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/sensors.h>

#include <dev/i2c/i2cvar.h>

/* ASMS Registers */
#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

/* Sensors */
#define ASMS_DATA_X             0
#define ASMS_DATA_Y             1
#define ASMS_DATA_Z             2
#define ASMS_NUM_SENSORS        3

struct asms_softc {
        struct device   sc_dev;
        i2c_tag_t       sc_tag;
        i2c_addr_t      sc_addr;

        struct ksensor  sc_sensor[ASMS_NUM_SENSORS];
        struct ksensordev sc_sensordev;
};

int     asms_match(struct device *, void *, void *);
void    asms_attach(struct device *, struct device *, void *);
void    asms_refresh(void *);

const struct cfattach asms_ca = {
        sizeof(struct asms_softc), asms_match, asms_attach
};

struct cfdriver asms_cd = {
        NULL, "asms", DV_DULL
};

int
asms_match(struct device *parent, void *match, void *aux)
{
        struct i2c_attach_args *ia = aux;

        if (strcmp(ia->ia_name, "AAPL,accelerometer_1") == 0)
                return (1);
        return (0);
}

void
asms_attach(struct device *parent, struct device *self, void *aux)
{
        struct asms_softc *sc = (struct asms_softc *)self;
        struct i2c_attach_args *ia = aux;
        u_int8_t cmd, data, rev1, rev2, ver1, ver2;
        int i, vflag = 0;

        sc->sc_tag = ia->ia_tag;
        sc->sc_addr = ia ->ia_addr;

        iic_acquire_bus(sc->sc_tag, 0);

        cmd = ASMS_REG_COMMAND; data = ASMS_CMD_START;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write command register\n");
                return;
        }
        delay(10000);

        cmd = ASMS_REG_RCONTROL1; data = 0x02;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write read control register\n");
                return;
        }

        cmd = ASMS_REG_RCONTROL2; data = 0x85;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write read control register\n");
                return;
        }

        cmd = ASMS_REG_RCONTROL3; data = 0x01;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write read control register\n");
                return;
        }

        cmd = ASMS_REG_COMMAND; data = ASMS_CMD_READ_MEM;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write command register\n");
                return;
        }
        delay(10000);

        cmd = ASMS_REG_RDATA1;
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &rev1, sizeof rev1, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot read data register\n");
                return;
        }

        cmd = ASMS_REG_RDATA2;
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &rev2, sizeof rev2, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot read data register\n");
                return;
        }

        cmd = ASMS_REG_COMMAND; data = ASMS_CMD_READ_VER;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write command register\n");
                return;
        }
        delay(10000);

        cmd = ASMS_REG_RDATA1;
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &ver1, sizeof ver1, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot read data register\n");
                return;
        }

        cmd = ASMS_REG_RDATA2;
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &ver2, sizeof ver2, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot read data register\n");
                return;
        }

        cmd = ASMS_REG_VENDOR;
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot read vendor register\n");
                return;
        }
        if (data & 0x10)
                vflag = 1;

        cmd = ASMS_REG_SENS_LOW; data = 0x15;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write sensibility low register\n");
                return;
        }

        cmd = ASMS_REG_SENS_HIGH; data = 0x60;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write sensibility high register\n");
                return;
        }

        cmd = ASMS_REG_CONTROL_X; data = 0x08;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write control X register\n");
                return;
        }

        cmd = ASMS_REG_CONTROL_Y; data= 0x0f;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write control Y register\n");
                return;
        }

        cmd = ASMS_REG_CONTROL_Z; data = 0x4f;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write control Z register\n");
                return;
        }

        cmd = ASMS_REG_UNKNOWN1; data = 0x14;
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &data, sizeof data, 0)) {
                iic_release_bus(sc->sc_tag, 0);
                printf(": cannot write unknown 1 register\n");
                return;
        }

        iic_release_bus(sc->sc_tag, 0);

        printf(": rev %x.%x, version %x.%x", rev1, rev2, ver1, ver2);

        /* Initialize sensor data. */
        strlcpy(sc->sc_sensordev.xname, sc->sc_dev.dv_xname,
            sizeof(sc->sc_sensordev.xname));

        sc->sc_sensor[ASMS_DATA_X].type = SENSOR_INTEGER;
        strlcpy(sc->sc_sensor[ASMS_DATA_X].desc, "X_ACCEL",
            sizeof(sc->sc_sensor[ASMS_DATA_X].desc));

        sc->sc_sensor[ASMS_DATA_Y].type = SENSOR_INTEGER;
        strlcpy(sc->sc_sensor[ASMS_DATA_Y].desc, "Y_ACCEL",
            sizeof(sc->sc_sensor[ASMS_DATA_Y].desc));

        sc->sc_sensor[ASMS_DATA_Z].type = SENSOR_INTEGER;
        strlcpy(sc->sc_sensor[ASMS_DATA_Z].desc, "Z_ACCEL",
            sizeof(sc->sc_sensor[ASMS_DATA_Z].desc));

        if (sensor_task_register(sc, asms_refresh, 5) == NULL) {
                printf(": unable to register update task\n");
                return;
        }

        for (i = 0; i < ASMS_NUM_SENSORS; i++)
                sensor_attach(&sc->sc_sensordev, &sc->sc_sensor[i]);
        sensordev_install(&sc->sc_sensordev);

        printf("\n");
}

void
asms_refresh(void *arg)
{
        struct asms_softc *sc = arg;
        u_int8_t cmd;
        int8_t sdata;

        iic_acquire_bus(sc->sc_tag, 0);

        cmd = ASMS_REG_DATA_X;
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &sdata, sizeof sdata, 0) == 0)
                sc->sc_sensor[ASMS_DATA_X].value = sdata;

        cmd = ASMS_REG_DATA_Y;
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &sdata, sizeof sdata, 0) == 0)
                sc->sc_sensor[ASMS_DATA_Y].value = sdata;

        cmd = ASMS_REG_DATA_Z;
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &cmd, sizeof cmd, &sdata, sizeof sdata, 0) == 0)
                sc->sc_sensor[ASMS_DATA_Z].value = sdata;

        iic_release_bus(sc->sc_tag, 0);
}