/*      $OpenBSD: gpiocharger.c,v 1.2 2022/04/06 18:59:28 naddy Exp $   */
/*
 * Copyright (c) 2021 Klemens Nanni <kn@openbsd.org>
 *
 * 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/gpio.h>
#include <sys/malloc.h>

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

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

#include <sys/sensors.h>

struct gpiocharger_softc {
        struct device            sc_dev;
        int                      sc_node;
        uint32_t                *sc_charger_pin;
        struct ksensor           sc_sensor;
        struct ksensordev        sc_sensordev;
};

int     gpiocharger_match(struct device *, void *, void *);
void    gpiocharger_attach(struct device *, struct device *, void *);

const struct cfattach gpiocharger_ca = {
        sizeof (struct gpiocharger_softc), gpiocharger_match, gpiocharger_attach
};

struct cfdriver gpiocharger_cd = {
        NULL, "gpiocharger", DV_DULL
};

void    gpiocharger_update_charger(void *);

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

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

void
gpiocharger_attach(struct device *parent, struct device *self, void *aux)
{
        struct gpiocharger_softc        *sc = (struct gpiocharger_softc *)self;
        struct fdt_attach_args          *faa = aux;
        char                            *charger_type, *gpios_property;
        int                              charger_type_len, gpios_len;
        int                              node = faa->fa_node;

        pinctrl_byname(node, "default");

        charger_type_len = OF_getproplen(node, "charger-type");
        if (charger_type_len <= 0)
                goto nocharger;
        gpios_property = "gpios";
        gpios_len = OF_getproplen(node, gpios_property);
        if (gpios_len <= 0) {
                gpios_property = "charger-status-gpios";
                gpios_len = OF_getproplen(node, gpios_property);
                if (gpios_len <= 0)
                        goto nocharger;
        }

        charger_type = malloc(charger_type_len, M_TEMP, M_WAITOK);
        OF_getprop(node, "charger-type", charger_type, charger_type_len);
        sc->sc_charger_pin = malloc(gpios_len, M_DEVBUF, M_WAITOK);
        OF_getpropintarray(node, gpios_property, sc->sc_charger_pin, gpios_len);
        gpio_controller_config_pin(sc->sc_charger_pin, GPIO_CONFIG_INPUT);

        strlcpy(sc->sc_sensor.desc, charger_type, sizeof(sc->sc_sensor.desc));
        strlcat(sc->sc_sensor.desc, " power supply",
            sizeof(sc->sc_sensor.desc));
        sc->sc_sensor.type = SENSOR_INDICATOR;
        sensor_attach(&sc->sc_sensordev, &sc->sc_sensor);
        strlcpy(sc->sc_sensordev.xname, sc->sc_dev.dv_xname,
            sizeof(sc->sc_sensordev.xname));
        sensordev_install(&sc->sc_sensordev);
        sensor_task_register(sc, gpiocharger_update_charger, 5);

        printf(": \"%s\"\n", charger_type);
        free(charger_type, M_TEMP, charger_type_len);
        return;

nocharger:
        printf(": no charger\n");
}

void
gpiocharger_update_charger(void *arg)
{
        struct gpiocharger_softc        *sc = arg;

        sc->sc_sensor.value = gpio_controller_get_pin(sc->sc_charger_pin);
}