/* $NetBSD: dstemp.c,v 1.17 2025/10/04 13:47:06 martin Exp $ */

/*-
 * Copyright (c) 2018 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: dstemp.c,v 1.17 2025/10/04 13:47:06 martin 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>

#define DSTEMP_CMD_START        0x51    /* command, no data */
#define DSTEMP_CMD_POR          0x54    /* command, no data */
#define DSTEMP_CMD_STOP         0x22    /* command, no data */
#define DSTEMP_TCURRENT         0xaa    /* current temperature, 2 bytes */
#define DSTEMP_THIGH            0xa1    /* high threshold, 2 bytes */
#define DSTEMP_TLOW             0xa2    /* low threshold, 2 bytes */
#define DSTEMP_CONFIG           0xac    /* 1 byte */

#define DSTEMP_1SHOT            0x01
#define DSTEMP_POL              0x02    /* Tout polarity, 1 - active high */
#define DSTEMP_8BIT             0x00
#define DSTEMP_10BIT            0x04
#define DSTEMP_11BIT            0x08
#define DSTEMP_12BIT            0x0c
#define DSTEMP_RES_MASK         0x0c
#define DSTEMP_NVB              0x10    /* EEPROM busy */
#define DSTEMP_TLF              0x20    /* temperature low flag */
#define DSTEMP_THF              0x40    /* temperature high flag */
#define DSTEMP_DONE             0x80

struct dstemp_softc {
        device_t                sc_dev;
        i2c_tag_t               sc_i2c;
        i2c_addr_t              sc_addr;
        struct sysmon_envsys    *sc_sme;
        envsys_data_t           sc_sensor_temp;
};

static int      dstemp_match(device_t, cfdata_t, void *);
static void     dstemp_attach(device_t, device_t, void *);

static void     dstemp_sensors_refresh(struct sysmon_envsys *, envsys_data_t *);
static void     dstemp_init(struct dstemp_softc *);

CFATTACH_DECL_NEW(dstemp, sizeof(struct dstemp_softc),
    dstemp_match, dstemp_attach, NULL, NULL);

static const struct device_compatible_entry compat_data[] = {
        { .compat = "dallas,ds1631" },
        { .compat = "ds1631" },
        DEVICE_COMPAT_EOL
};

static int
dstemp_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) == 0x48)
                return I2C_MATCH_ADDRESS_ONLY;

        return 0;
}

static void
dstemp_attach(device_t parent, device_t self, void *aux)
{
        struct dstemp_softc *sc = device_private(self);
        struct i2c_attach_args *ia = aux;
        char name[64] = "temperature";

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

        aprint_naive("\n");
        aprint_normal(": DS1361\n");

        dstemp_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 = dstemp_sensors_refresh;

        sc->sc_sensor_temp.units = ENVSYS_STEMP;
        sc->sc_sensor_temp.state = ENVSYS_SINVALID;
        sc->sc_sensor_temp.flags = ENVSYS_FHAS_ENTROPY;

        if (device_getprop_string(self, "s00", name, sizeof(name)) < 0) {
                device_getprop_string(self, "saa", name, sizeof(name));
        }

        strncpy(sc->sc_sensor_temp.desc, name, sizeof(sc->sc_sensor_temp.desc));

        sysmon_envsys_sensor_attach(sc->sc_sme, &sc->sc_sensor_temp);

        sysmon_envsys_register(sc->sc_sme);
}

static void
dstemp_init(struct dstemp_softc *sc)
{
        int error;
        uint8_t cmd[2], data;

        if (iic_acquire_bus(sc->sc_i2c, 0))
                return;
        cmd[0] = DSTEMP_CONFIG;
        data = 0;
        error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, cmd, 1, &data, 1, 0);
        /* we don't want to change the POL bit, so preserve it */
        cmd[1] = (data & DSTEMP_POL) | DSTEMP_12BIT;
        error |= iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, cmd, 2, NULL, 0, 0);
        /* ... and start converting */
        cmd[0] = DSTEMP_CMD_START;
        error |= iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, cmd, 1, NULL, 0, 0);
        if (error) aprint_error_dev(sc->sc_dev, "chip initialization failed\n");
        iic_release_bus(sc->sc_i2c, 0);
}

static void
dstemp_sensors_refresh(struct sysmon_envsys *sme, envsys_data_t *edata)
{
        struct dstemp_softc *sc = sme->sme_cookie;
        uint8_t cmd = DSTEMP_TCURRENT;
        uint16_t data = 0;
        int error;

                
        error = iic_acquire_bus(sc->sc_i2c, 0);
        if (error == 0) {
                error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP,
                    sc->sc_addr, &cmd, 1, &data, 2, 0);
                iic_release_bus(sc->sc_i2c, 0);
        }

        if (error) {
                edata->state = ENVSYS_SINVALID;
        } else {
                edata->value_cur =
                    ((uint64_t)(be16toh(data) >> 4) * 62500) +
                    + 273150000;
                if (edata->value_cur > (273150000 + 120000000)) {
                        edata->state = ENVSYS_SINVALID;
                } else
                        edata->state = ENVSYS_SVALID;
        }
}