/*      $OpenBSD: w83793g.c,v 1.6 2022/04/06 18:59:28 naddy Exp $       */

/*
 * Copyright (c) 2007 Constantine A. Murenin <cnst+openbsd@bugmail.mojo.ru>
 *
 * 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.
 */

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

#include <dev/i2c/i2cvar.h>

/* Winbond W83793G Hardware Monitor */

#define WB_BANKSELECT   0x00

/* Voltage */
#define WB_NUM_VOLTS    10

static const char *wb_volt_desc[WB_NUM_VOLTS] = {
        "VCore", "VCore", "VTT",
        "", "", "3.3V", "12V", "5VDD", "5VSB", "VBat"
};

#define WB_VCOREA       0x10
#define WB_VCOREB       0x11
#define WB_VTT          0x12
#define WB_VLOW         0x1b

#define WB_VSENS1       0x14
#define WB_VSENS2       0x15
#define WB_3VSEN        0x16
#define WB_12VSEN       0x17
#define WB_5VDD         0x18
#define WB_5VSB         0x19
#define WB_VBAT         0x1a

/* Temperature */
#define WB_NUM_TEMPS    6

#define WB_TD_COUNT     4
#define WB_TD_START     0x1c
#define WB_TDLOW        0x22

#define WB_TR_COUNT     2
#define WB_TR_START     0x20

/* Fan */
#define WB_NUM_FANS     12
#define WB_FAN_START    0x23


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

        struct ksensor  sc_sensors[WB_NUM_VOLTS + WB_NUM_TEMPS + WB_NUM_FANS];
        struct ksensordev sc_sensordev;
};


int     wbng_match(struct device *, void *, void *);
void    wbng_attach(struct device *, struct device *, void *);
void    wbng_refresh(void *);

void    wbng_refresh_volts(struct wbng_softc *);
void    wbng_refresh_temps(struct wbng_softc *);
void    wbng_refresh_fans(struct wbng_softc *);

uint8_t wbng_readreg(struct wbng_softc *, uint8_t);
void    wbng_writereg(struct wbng_softc *, uint8_t, uint8_t);


const struct cfattach wbng_ca = {
        sizeof(struct wbng_softc), wbng_match, wbng_attach
};

struct cfdriver wbng_cd = {
        NULL, "wbng", DV_DULL
};


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

        if (strcmp(ia->ia_name, "w83793g") == 0)
                return 1;
        return 0;
}

void
wbng_attach(struct device *parent, struct device *self, void *aux)
{
        struct wbng_softc *sc = (struct wbng_softc *)self;
        struct i2c_attach_args *ia = aux;
        int i, j;

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

        printf(": %s", ia->ia_name);

        strlcpy(sc->sc_sensordev.xname, sc->sc_dev.dv_xname,
            sizeof(sc->sc_sensordev.xname));

        for (i = 0; i < WB_NUM_VOLTS; i++) {
                strlcpy(sc->sc_sensors[i].desc, wb_volt_desc[i],
                    sizeof(sc->sc_sensors[i].desc));
                sc->sc_sensors[i].type = SENSOR_VOLTS_DC;
        }

        for (j = i + WB_NUM_TEMPS; i < j; i++)
                sc->sc_sensors[i].type = SENSOR_TEMP;

        for (j = i + WB_NUM_FANS; i < j; i++)
                sc->sc_sensors[i].type = SENSOR_FANRPM;

        for (i = 0; i < WB_NUM_VOLTS + WB_NUM_TEMPS + WB_NUM_FANS; i++)
                sensor_attach(&sc->sc_sensordev, &sc->sc_sensors[i]);

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

        sensordev_install(&sc->sc_sensordev);
        printf("\n");
}

void
wbng_refresh(void *arg)
{
        struct wbng_softc *sc = arg;
        uint8_t bsr;

        iic_acquire_bus(sc->sc_tag, 0);

        bsr = wbng_readreg(sc, WB_BANKSELECT);
        if ((bsr & 0x07) != 0x0)
                wbng_writereg(sc, WB_BANKSELECT, bsr & 0xf8);

        wbng_refresh_volts(sc);
        wbng_refresh_temps(sc);
        wbng_refresh_fans(sc);

        if ((bsr & 0x07) != 0x0)
                wbng_writereg(sc, WB_BANKSELECT, bsr);

        iic_release_bus(sc->sc_tag, 0);
}

void
wbng_refresh_volts(struct wbng_softc *sc)
{
        struct ksensor *s = &sc->sc_sensors[0];
        uint8_t vlow, data;

        /* high precision voltage sensors */

        vlow = wbng_readreg(sc, WB_VLOW);

        data = wbng_readreg(sc, WB_VCOREA);
        s[0].value = ((data << 3) | (((vlow & 0x03)) << 1)) * 1000;

        data = wbng_readreg(sc, WB_VCOREB);
        s[1].value = ((data << 3) | (((vlow & 0x0c) >> 2) << 1)) * 1000;

        data = wbng_readreg(sc, WB_VTT);
        s[2].value = ((data << 3) | (((vlow & 0x30) >> 4) << 1)) * 1000;

        /* low precision voltage sensors */

        data = wbng_readreg(sc, WB_VSENS1);
        s[3].value = (data << 4) * 1000;

        data = wbng_readreg(sc, WB_VSENS2);
        s[4].value = (data << 4) * 1000;

        data = wbng_readreg(sc, WB_3VSEN);
        s[5].value = (data << 4) * 1000;

        data = wbng_readreg(sc, WB_12VSEN);
        s[6].value = (data << 4) * 6100;        /*XXX, the factor is a guess */

        data = wbng_readreg(sc, WB_5VDD);
        s[7].value = (data << 4) * 1500 + 150000;

        data = wbng_readreg(sc, WB_5VSB);
        s[8].value = (data << 4) * 1500 + 150000;

        data = wbng_readreg(sc, WB_VBAT);
        s[9].value = (data << 4) * 1000;
}

void
wbng_refresh_temps(struct wbng_softc *sc)
{
        struct ksensor *s = &sc->sc_sensors[WB_NUM_VOLTS];
        int data, i;
        uint8_t tdlow, low;

        /* high precision temperature sensors */
        tdlow = wbng_readreg(sc, WB_TDLOW);
        for (i = 0; i < WB_TD_COUNT; i++) {
                data = wbng_readreg(sc, WB_TD_START + i);
                /*
                 * XXX: datasheet says nothing about acceptable values,
                 * let's consider only values between -55 degC and +125 degC.
                 */
                if (data > 0x7f && data < 0xc9) {
                        s[i].flags |= SENSOR_FINVALID;
                        s[i].value = 0;
                        continue;
                }
                if (data & 0x80)
                        data -= 0x100;
                low = (tdlow & (0x03 << (i * 2))) >> (i * 2);
                s[i].value = data * 1000000 + low * 250000 + 273150000;
                s[i].flags &= ~SENSOR_FINVALID;
        }
        s += i;

        /* low precision temperature sensors */
        for (i = 0; i < WB_TR_COUNT; i++) {
                data = wbng_readreg(sc, WB_TR_START + i);
                /*
                 * XXX: datasheet says nothing about acceptable values,
                 * let's consider only values between -55 degC and +125 degC.
                 */
                if (data > 0x7f && data < 0xc9) {
                        s[i].flags |= SENSOR_FINVALID;
                        s[i].value = 0;
                        continue;
                }
                if (data & 0x80)
                        data -= 0x100;
                s[i].value = data * 1000000 + 273150000;
                s[i].flags &= ~SENSOR_FINVALID;
        }
}

void
wbng_refresh_fans(struct wbng_softc *sc)
{
        struct ksensor *s = &sc->sc_sensors[WB_NUM_VOLTS + WB_NUM_TEMPS];
        int i;

        for (i = 0; i < WB_NUM_FANS; i++) {
                uint8_t h = wbng_readreg(sc, WB_FAN_START + i * 2);
                uint8_t l = wbng_readreg(sc, WB_FAN_START + i * 2 + 1);
                uint16_t b = h << 8 | l;

                if (b >= 0x0fff || b == 0x0f00 || b == 0x0000) {
                        s[i].flags |= SENSOR_FINVALID;
                        s[i].value = 0;
                } else {
                        s[i].flags &= ~SENSOR_FINVALID;
                        s[i].value = 1350000 / b;
                }
        }
}

uint8_t
wbng_readreg(struct wbng_softc *sc, uint8_t reg)
{
        uint8_t data;

        iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
            sc->sc_addr, &reg, sizeof reg, &data, sizeof data, 0);

        return data;
}

void
wbng_writereg(struct wbng_softc *sc, uint8_t reg, uint8_t data)
{
        iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
            sc->sc_addr, &reg, sizeof reg, &data, sizeof data, 0);
}