/*      $OpenBSD: rs5c372.c,v 1.8 2022/10/12 13:39:50 kettenis Exp $    */
/*      $NetBSD: rs5c372.c,v 1.5 2006/03/29 06:41:24 thorpej Exp $      */

/*
 * Copyright (c) 2005 Kimihiro Nonaka
 * 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 WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
 * 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/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/kernel.h>
#include <sys/fcntl.h>
#include <sys/uio.h>
#include <sys/conf.h>
#include <sys/event.h>

#include <dev/clock_subr.h>

#include <dev/i2c/i2cvar.h>

/*
 * RS5C372[AB] Real-Time Clock
 */

#define RICOHRTC_ADDR           0x32    /* Fixed I2C Slave Address */

#define RICOHRTC_SECONDS        0
#define RICOHRTC_MINUTES        1
#define RICOHRTC_HOURS          2
#define RICOHRTC_DAY            3
#define RICOHRTC_DATE           4
#define RICOHRTC_MONTH          5
#define RICOHRTC_YEAR           6
#define RICOHRTC_CLOCK_CORRECT  7
#define RICOHRTC_ALARMA_MIN     8
#define RICOHRTC_ALARMA_HOUR    9
#define RICOHRTC_ALARMA_DATE    10
#define RICOHRTC_ALARMB_MIN     11
#define RICOHRTC_ALARMB_HOUR    12
#define RICOHRTC_ALARMB_DATE    13
#define RICOHRTC_CONTROL1       14
#define RICOHRTC_CONTROL2       15
#define RICOHRTC_NREGS          16
#define RICOHRTC_NRTC_REGS      7

/*
 * Bit definitions.
 */
#define RICOHRTC_SECONDS_MASK   0x7f
#define RICOHRTC_MINUTES_MASK   0x7f
#define RICOHRTC_HOURS_12HRS_PM (1u << 5)       /* If 12 hr mode, set = PM */
#define RICOHRTC_HOURS_12MASK   0x1f
#define RICOHRTC_HOURS_24MASK   0x3f
#define RICOHRTC_DAY_MASK       0x07
#define RICOHRTC_DATE_MASK      0x3f
#define RICOHRTC_MONTH_MASK     0x1f
#define RICOHRTC_CONTROL2_24HRS (1u << 5)
#define RICOHRTC_CONTROL2_XSTP  (1u << 4)       /* read */
#define RICOHRTC_CONTROL2_ADJ   (1u << 4)       /* write */
#define RICOHRTC_CONTROL2_NCLEN (1u << 3)
#define RICOHRTC_CONTROL2_CTFG  (1u << 2)
#define RICOHRTC_CONTROL2_AAFG  (1u << 1)
#define RICOHRTC_CONTROL2_BAFG  (1u << 0)

struct ricohrtc_softc {
        struct device sc_dev;
        i2c_tag_t sc_tag;
        int sc_address;
        struct todr_chip_handle sc_todr;
};

int ricohrtc_match(struct device *, void *, void *);
void ricohrtc_attach(struct device *, struct device *, void *);

const struct cfattach ricohrtc_ca = {
        sizeof(struct ricohrtc_softc), ricohrtc_match, ricohrtc_attach
};

struct cfdriver ricohrtc_cd = {
        NULL, "ricohrtc", DV_DULL
};

void ricohrtc_reg_write(struct ricohrtc_softc *, int, uint8_t);
int ricohrtc_clock_read(struct ricohrtc_softc *, struct clock_ymdhms *);
int ricohrtc_clock_write(struct ricohrtc_softc *, struct clock_ymdhms *);
int ricohrtc_gettime(struct todr_chip_handle *, struct timeval *);
int ricohrtc_settime(struct todr_chip_handle *, struct timeval *);

int
ricohrtc_match(struct device *parent, void *v, void *arg)
{
        struct i2c_attach_args *ia = arg;
#ifdef PARANOID_CHECKS
        u_int8_t data, cmd;
#endif

        if (ia->ia_addr != RICOHRTC_ADDR)
                return (0);

#ifdef PARANOID_CHECKS
        /* Verify that the 'reserved bits in a few registers read 0 */
        if (iic_acquire_bus(ia->ia_tag, I2C_F_POLL)) {
                printf("ricohrtc acquire fail\n");
                return (0);
        }

        cmd = RICOHRTC_SECONDS;
        if (iic_exec(ia->ia_tag, I2C_OP_READ_WITH_STOP, ia->ia_addr,
            &cmd, sizeof cmd, &data, sizeof data, I2C_F_POLL)) {
                iic_release_bus(ia->ia_tag, I2C_F_POLL);
                printf("ricohrtc read %d fail\n", cmd);
                return (0);
        }
        if ((data & ~RICOHRTC_SECONDS_MASK) != 0) {
                iic_release_bus(ia->ia_tag, I2C_F_POLL);
                printf("ricohrtc second %d\n",data);
                return (0);
        }

        cmd = RICOHRTC_MINUTES;
        if (iic_exec(ia->ia_tag, I2C_OP_READ_WITH_STOP, ia->ia_addr,
            &cmd, sizeof cmd, &data, sizeof data, I2C_F_POLL)) {
                iic_release_bus(ia->ia_tag, I2C_F_POLL);
                printf("ricohrtc read %d fail\n", cmd);
                return (0);
        }

        if ((data & ~RICOHRTC_MINUTES_MASK) != 0) {
                iic_release_bus(ia->ia_tag, I2C_F_POLL);
                printf("ricohrtc minute %d\n",data);
                return (0);
        }

        cmd = RICOHRTC_HOURS;
        if (iic_exec(ia->ia_tag, I2C_OP_READ_WITH_STOP, ia->ia_addr,
            &cmd, sizeof cmd, &data, sizeof data, I2C_F_POLL)) {
                iic_release_bus(ia->ia_tag, I2C_F_POLL);
                printf("ricohrtc read %d fail\n", cmd);
                return (0);
        }
        if ((data & ~RICOHRTC_HOURS_24MASK) != 0) {
                iic_release_bus(ia->ia_tag, I2C_F_POLL);
                printf("ricohrtc hour %d\n",data);
                return (0);
        }
        iic_release_bus(ia->ia_tag, I2C_F_POLL);

#endif
        return (1);
}

void
ricohrtc_attach(struct device *parent, struct device *self, void *arg)
{
        struct ricohrtc_softc *sc = (struct ricohrtc_softc *)self;
        struct i2c_attach_args *ia = arg;

        printf(": RICOH RS5C372[AB] Real-time Clock\n");

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

        sc->sc_todr.cookie = sc;
        sc->sc_todr.todr_gettime = ricohrtc_gettime;
        sc->sc_todr.todr_settime = ricohrtc_settime;
        sc->sc_todr.todr_setwen = NULL;
        sc->sc_todr.todr_quality = 1000;
        todr_attach(&sc->sc_todr);

        /* Initialize RTC */
        ricohrtc_reg_write(sc, RICOHRTC_CONTROL2, RICOHRTC_CONTROL2_24HRS);
        ricohrtc_reg_write(sc, RICOHRTC_CONTROL1, 0);
}

int
ricohrtc_gettime(struct todr_chip_handle *ch, struct timeval *tv)
{
        struct ricohrtc_softc *sc = ch->cookie;
        struct clock_ymdhms dt;

        memset(&dt, 0, sizeof(dt));
        if (ricohrtc_clock_read(sc, &dt) == 0)
                return (-1);

        tv->tv_sec = clock_ymdhms_to_secs(&dt);
        tv->tv_usec = 0;
        return (0);
}

int
ricohrtc_settime(struct todr_chip_handle *ch, struct timeval *tv)
{
        struct ricohrtc_softc *sc = ch->cookie;
        struct clock_ymdhms dt;

        clock_secs_to_ymdhms(tv->tv_sec, &dt);

        if (ricohrtc_clock_write(sc, &dt) == 0)
                return (-1);
        return (0);
}

void
ricohrtc_reg_write(struct ricohrtc_softc *sc, int reg, uint8_t val)
{
        uint8_t cmd;

        iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
        reg &= 0xf;
        cmd = (reg << 4);
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_address,
            &cmd, sizeof cmd, &val, sizeof val, I2C_F_POLL)) {
                iic_release_bus(sc->sc_tag, I2C_F_POLL);
                printf("%s: ricohrtc_reg_write: failed to write reg%d\n",
                    sc->sc_dev.dv_xname, reg);
                return;
        }
        iic_release_bus(sc->sc_tag, I2C_F_POLL);
}

int
ricohrtc_clock_read(struct ricohrtc_softc *sc, struct clock_ymdhms *dt)
{
        uint8_t bcd[RICOHRTC_NRTC_REGS];
        uint8_t cmd;

        iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
        cmd = (RICOHRTC_SECONDS << 4);
        if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_address,
            &cmd, sizeof cmd, bcd, RICOHRTC_NRTC_REGS, I2C_F_POLL)) {
                iic_release_bus(sc->sc_tag, I2C_F_POLL);
                printf("%s: ricohrtc_clock_read: failed to read rtc\n",
                    sc->sc_dev.dv_xname);
                return (0);
        }
        iic_release_bus(sc->sc_tag, I2C_F_POLL);

        /*
         * Convert the RICOHRTC's register values into something useable
         */
        dt->dt_sec = FROMBCD(bcd[RICOHRTC_SECONDS] & RICOHRTC_SECONDS_MASK);
        dt->dt_min = FROMBCD(bcd[RICOHRTC_MINUTES] & RICOHRTC_MINUTES_MASK);
        dt->dt_hour = FROMBCD(bcd[RICOHRTC_HOURS] & RICOHRTC_HOURS_24MASK);
        dt->dt_day = FROMBCD(bcd[RICOHRTC_DATE] & RICOHRTC_DATE_MASK);
        dt->dt_mon = FROMBCD(bcd[RICOHRTC_MONTH] & RICOHRTC_MONTH_MASK);
        dt->dt_year = FROMBCD(bcd[RICOHRTC_YEAR]) + POSIX_BASE_YEAR;
        return (1);
}

int
ricohrtc_clock_write(struct ricohrtc_softc *sc, struct clock_ymdhms *dt)
{
        uint8_t bcd[RICOHRTC_NRTC_REGS];
        uint8_t cmd;

        /*
         * Convert our time representation into something the RICOHRTC
         * can understand.
         */
        bcd[RICOHRTC_SECONDS] = TOBCD(dt->dt_sec);
        bcd[RICOHRTC_MINUTES] = TOBCD(dt->dt_min);
        bcd[RICOHRTC_HOURS] = TOBCD(dt->dt_hour);
        bcd[RICOHRTC_DATE] = TOBCD(dt->dt_day);
        bcd[RICOHRTC_DAY] = TOBCD(dt->dt_wday);
        bcd[RICOHRTC_MONTH] = TOBCD(dt->dt_mon);
        bcd[RICOHRTC_YEAR] = TOBCD(dt->dt_year - POSIX_BASE_YEAR);

        iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
        cmd = (RICOHRTC_SECONDS << 4);
        if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_address,
            &cmd, sizeof cmd, bcd, RICOHRTC_NRTC_REGS, I2C_F_POLL)) {
                iic_release_bus(sc->sc_tag, I2C_F_POLL);
                printf("%s: ricohrtc_clock_write: failed to write rtc\n",
                    sc->sc_dev.dv_xname);
                return (0);
        }
        iic_release_bus(sc->sc_tag, I2C_F_POLL);
        return (1);
}