root/sys/dev/i2c/lm78_i2c.c
/*      $OpenBSD: lm78_i2c.c,v 1.5 2022/04/06 18:59:28 naddy Exp $      */

/*
 * Copyright (c) 2005 Mark Kettenis
 *
 * 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>
#include <dev/ic/lm78var.h>

struct lm_i2c_softc {
        struct lm_softc sc_lmsc;
        i2c_tag_t       sc_tag;
        i2c_addr_t      sc_addr;
};

int lm_i2c_match(struct device *, void *, void *);
void lm_i2c_attach(struct device *, struct device *, void *);
u_int8_t lm_i2c_readreg(struct lm_softc *, int);
void lm_i2c_writereg(struct lm_softc *, int, int);

const struct cfattach lm_i2c_ca = {
        sizeof(struct lm_i2c_softc), lm_i2c_match, lm_i2c_attach
};

int
lm_i2c_match(struct device *parent, void *match, void *aux)
{
        struct i2c_attach_args *ia = aux;

        if (strcmp(ia->ia_name, "as99127f") == 0 ||
            strcmp(ia->ia_name, "w83627dhg") == 0 ||
            strcmp(ia->ia_name, "w83627hf") == 0 ||
            strcmp(ia->ia_name, "w83781d") == 0 ||
            strcmp(ia->ia_name, "w83782d") == 0 ||
            strcmp(ia->ia_name, "w83783s") == 0 ||
            strcmp(ia->ia_name, "w83791d") == 0 ||
            strcmp(ia->ia_name, "w83792d") == 0) {
                return (1);
        }
        /*
         * XXX This chip doesn't have any real sensors, but we match
         * it for now, just to knock out its satellites.
         */
        if (strcmp(ia->ia_name, "w83791sd") == 0) {
                return (1);
        }
        return (0);
}

void
lm_i2c_attach(struct device *parent, struct device *self, void *aux)
{
        struct lm_i2c_softc *sc = (struct lm_i2c_softc *)self;
        struct i2c_attach_args *ia = aux;
        u_int8_t cmd, data;

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

        /* Bus-independent attachment. */
        sc->sc_lmsc.lm_writereg = lm_i2c_writereg;
        sc->sc_lmsc.lm_readreg = lm_i2c_readreg;
        lm_attach(&sc->sc_lmsc);

        /* Remember we attached to iic(4). */
        sc->sc_lmsc.sbusaddr = ia->ia_addr;

        iic_acquire_bus(sc->sc_tag, 0);

        cmd = 0x4a;
        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);

        /* Make the bus scan ignore the satellites. */
        iic_ignore_addr(0x48 + (data & 0x7));
        iic_ignore_addr(0x48 + ((data >> 4) & 0x7));
}

u_int8_t
lm_i2c_readreg(struct lm_softc *lmsc, int reg)
{
        struct lm_i2c_softc *sc = (struct lm_i2c_softc *)lmsc;
        u_int8_t cmd, data;

        iic_acquire_bus(sc->sc_tag, 0);

        cmd = reg;
        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);

        return data;
}

void
lm_i2c_writereg(struct lm_softc *lmsc, int reg, int val)
{
        struct lm_i2c_softc *sc = (struct lm_i2c_softc *)lmsc;
        u_int8_t cmd, data;

        iic_acquire_bus(sc->sc_tag, 0);

        cmd = reg;
        data = val;
        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);
}