/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2009 Oleksandr Tymoshenko <gonzo@freebsd.org>
 * 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 THE AUTHOR AND CONTRIBUTORS ``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 THE AUTHOR OR CONTRIBUTORS 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/cdefs.h>
#include "opt_platform.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/gpio.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mutex.h>

#include <dev/gpio/gpiobusvar.h>
#include <dev/led/led.h>

#include "gpiobus_if.h"

/*
 * Only one pin for led
 */
#define GPIOLED_PIN     0

#define GPIOLED_LOCK(_sc)               mtx_lock(&(_sc)->sc_mtx)
#define GPIOLED_UNLOCK(_sc)             mtx_unlock(&(_sc)->sc_mtx)
#define GPIOLED_LOCK_INIT(_sc)          mtx_init(&(_sc)->sc_mtx,        \
    device_get_nameunit((_sc)->sc_dev), "gpioled", MTX_DEF)
#define GPIOLED_LOCK_DESTROY(_sc)       mtx_destroy(&(_sc)->sc_mtx)

struct gpioled_softc
{
        device_t        sc_dev;
        device_t        sc_busdev;
        struct mtx      sc_mtx;
        struct cdev     *sc_leddev;
        int     sc_softinvert;
};

static void gpioled_control(void *, int);
static int gpioled_probe(device_t);
static int gpioled_attach(device_t);
static int gpioled_detach(device_t);

static void
gpioled_control(void *priv, int onoff)
{
        struct gpioled_softc *sc;

        sc = (struct gpioled_softc *)priv;
        if (sc->sc_softinvert)
                onoff = !onoff;
        GPIOLED_LOCK(sc);
        GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
            onoff ? GPIO_PIN_HIGH : GPIO_PIN_LOW);
        GPIOLED_UNLOCK(sc);
}

static int
gpioled_probe(device_t dev)
{
        device_set_desc(dev, "GPIO led");

        return (BUS_PROBE_DEFAULT);
}

static int
gpioled_inv(device_t dev, uint32_t *pin_flags)
{
        struct gpioled_softc *sc;
        int invert;
        uint32_t pin_caps;

        sc = device_get_softc(dev);

        if (resource_int_value(device_get_name(dev),
            device_get_unit(dev), "invert", &invert))
                invert = 0;

        if (GPIOBUS_PIN_GETCAPS(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
            &pin_caps) != 0) {
                if (bootverbose)
                        device_printf(sc->sc_dev, "unable to get pin caps\n");
                return (-1);
        }
        if (pin_caps & GPIO_PIN_INVOUT)
                *pin_flags &= ~GPIO_PIN_INVOUT;
        sc->sc_softinvert = 0;
        if (invert) {
                const char *invmode;

                if (resource_string_value(device_get_name(dev),
                    device_get_unit(dev), "invmode", &invmode))
                        invmode = NULL;

                if (invmode) {
                        if (!strcmp(invmode, "sw"))
                                sc->sc_softinvert = 1;
                        else if (!strcmp(invmode, "hw")) {
                                if (pin_caps & GPIO_PIN_INVOUT)
                                        *pin_flags |= GPIO_PIN_INVOUT;
                                else {
                                        device_printf(sc->sc_dev, "hardware pin inversion not supported\n");
                                        return (-1);
                                }
                        } else {
                                if (strcmp(invmode, "auto") != 0)
                                        device_printf(sc->sc_dev, "invalid pin inversion mode\n");
                                invmode = NULL;
                        }
                }
                /*
                 * auto inversion mode: use hardware support if available, else fallback to
                 * software emulation.
                 */
                if (invmode == NULL) {
                        if (pin_caps & GPIO_PIN_INVOUT)
                                *pin_flags |= GPIO_PIN_INVOUT;
                        else
                                sc->sc_softinvert = 1;
                }
        }
        MPASS(!invert ||
            (((*pin_flags & GPIO_PIN_INVOUT) != 0) && !sc->sc_softinvert) ||
            (((*pin_flags & GPIO_PIN_INVOUT) == 0) && sc->sc_softinvert));
        return (invert);
}

static int
gpioled_attach(device_t dev)
{
        struct gpioled_softc *sc;
        int state;
        const char *name;
        uint32_t pin_flags;
        int invert;

        sc = device_get_softc(dev);
        sc->sc_dev = dev;
        sc->sc_busdev = device_get_parent(dev);
        GPIOLED_LOCK_INIT(sc);

        if (resource_string_value(device_get_name(dev),
            device_get_unit(dev), "name", &name))
                name = NULL;

        if (resource_int_value(device_get_name(dev),
            device_get_unit(dev), "state", &state))
                state = 0;

        pin_flags = GPIO_PIN_OUTPUT;
        invert = gpioled_inv(dev, &pin_flags);
        if (invert < 0)
                return (ENXIO);
        device_printf(sc->sc_dev, "state %d invert %s\n",
            state, (invert ? (sc->sc_softinvert ? "sw" : "hw") : "no"));
        if (GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
            pin_flags) != 0) {
                if (bootverbose)
                        device_printf(sc->sc_dev, "unable to set pin flags, %#x\n", pin_flags);
                return (ENXIO);
        }

        sc->sc_leddev = led_create_state(gpioled_control, sc, name ? name :
            device_get_nameunit(dev), state);

        return (0);
}

static int
gpioled_detach(device_t dev)
{
        struct gpioled_softc *sc;

        sc = device_get_softc(dev);
        if (sc->sc_leddev) {
                led_destroy(sc->sc_leddev);
                sc->sc_leddev = NULL;
        }
        GPIOLED_LOCK_DESTROY(sc);
        return (0);
}

static device_method_t gpioled_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         gpioled_probe),
        DEVMETHOD(device_attach,        gpioled_attach),
        DEVMETHOD(device_detach,        gpioled_detach),

        DEVMETHOD_END
};

static driver_t gpioled_driver = {
        "gpioled",
        gpioled_methods,
        sizeof(struct gpioled_softc),
};

DRIVER_MODULE(gpioled, gpiobus, gpioled_driver, 0, 0);
MODULE_DEPEND(gpioled, gpiobus, 1, 1, 1);
MODULE_VERSION(gpioled, 1);