/*      $OpenBSD: gpiorestart.c,v 1.1 2022/06/09 12:13:56 kettenis Exp $        */
/*
 * Copyright (c) 2022 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/malloc.h>

#include <machine/bus.h>
#include <machine/fdt.h>

#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_gpio.h>
#include <dev/ofw/fdt.h>

extern void (*cpuresetfn)(void);

struct gpiorestart_softc {
        struct device   sc_dev;
        uint32_t        *sc_gpio;
        uint32_t        sc_active_delay;
        uint32_t        sc_inactive_delay;
        uint32_t        sc_wait_delay;
};

int     gpiorestart_match(struct device *, void *, void *);
void    gpiorestart_attach(struct device *, struct device *, void *);

const struct cfattach gpiorestart_ca = {
        sizeof(struct gpiorestart_softc), gpiorestart_match, gpiorestart_attach
};

struct cfdriver gpiorestart_cd = {
        NULL, "gpiorestart", DV_DULL
};

void    gpiorestart_reset(void);

int
gpiorestart_match(struct device *parent, void *match, void *aux)
{
        struct fdt_attach_args *faa = aux;

        return OF_is_compatible(faa->fa_node, "gpio-restart");
}

void
gpiorestart_attach(struct device *parent, struct device *self, void *aux)
{
        struct gpiorestart_softc *sc = (struct gpiorestart_softc *)self;
        struct fdt_attach_args *faa = aux;
        int len;

        len = OF_getproplen(faa->fa_node, "gpios");
        if (len <= 0) {
                printf(": no gpio\n");
                return;
        }

        sc->sc_gpio = malloc(len, M_DEVBUF, M_WAITOK);
        OF_getpropintarray(faa->fa_node, "gpios", sc->sc_gpio, len);

        sc->sc_active_delay =
            OF_getpropint(faa->fa_node, "active-delay", 100) * 1000;
        sc->sc_inactive_delay =
            OF_getpropint(faa->fa_node, "inactive-delay", 100) * 1000;
        sc->sc_wait_delay =
            OF_getpropint(faa->fa_node, "wait-delay", 3000) * 1000;

        if (cpuresetfn == NULL)
                cpuresetfn = gpiorestart_reset;

        printf("\n");
}

void
gpiorestart_reset(void)
{
        struct gpiorestart_softc *sc = gpiorestart_cd.cd_devs[0];

        gpio_controller_config_pin(sc->sc_gpio, GPIO_CONFIG_OUTPUT);
        gpio_controller_set_pin(sc->sc_gpio, 1);
        delay(sc->sc_active_delay);
        gpio_controller_set_pin(sc->sc_gpio, 0);
        delay(sc->sc_inactive_delay);
        gpio_controller_set_pin(sc->sc_gpio, 1);
        delay(sc->sc_wait_delay);
}