/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2018 Rubicon Communications, LLC (Netgate)
 *
 * 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/param.h>
#include <sys/systm.h>
#include <sys/bus.h>

#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <sys/lock.h>
#include <sys/mutex.h>

#include <machine/bus.h>
#include <machine/resource.h>
#include <machine/intr.h>

#include <dev/syscon/syscon.h>

#include <dev/fdt/fdt_pinctrl.h>

#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>

#include "syscon_if.h"

#define PINS_PER_REG    8
#define BITS_PER_PIN    4
#define PINS_MASK       0xf
#define MAX_PIN_FUNC    5

struct mv_pins {
        const char      *name;
        const char      *functions[MAX_PIN_FUNC];
};

struct mv_padconf {
        const struct mv_pins    *pins;
        size_t          npins;
};

const static struct mv_pins ap806_pins[] = {
        {"mpp0", {"gpio", "sdio", NULL, "spi0"}},
        {"mpp1", {"gpio", "sdio", NULL, "spi0"}},
        {"mpp2", {"gpio", "sdio", NULL, "spi0"}},
        {"mpp3", {"gpio", "sdio", NULL, "spi0"}},
        {"mpp4", {"gpio", "sdio", NULL, "i2c0"}},
        {"mpp5", {"gpio", "sdio", NULL, "i2c0"}},
        {"mpp6", {"gpio", "sdio", NULL, NULL}},
        {"mpp7", {"gpio", "sdio", NULL, "uart1"}},
        {"mpp8", {"gpio", "sdio", NULL, "uart1"}},
        {"mpp9", {"gpio", "sdio", NULL, "spi0"}},
        {"mpp10", {"gpio", "sdio", NULL, NULL}},
        {"mpp11", {"gpio", NULL, NULL, "uart0"}},
        {"mpp12", {"gpio", "sdio", "sdio", NULL}},
        {"mpp13", {"gpio", NULL, NULL}},
        {"mpp14", {"gpio", NULL, NULL}},
        {"mpp15", {"gpio", NULL, NULL}},
        {"mpp16", {"gpio", NULL, NULL}},
        {"mpp17", {"gpio", NULL, NULL}},
        {"mpp18", {"gpio", NULL, NULL}},
        {"mpp19", {"gpio", NULL, NULL, "uart0", "sdio"}},
};

const struct mv_padconf ap806_padconf = {
        .npins = nitems(ap806_pins),
        .pins = ap806_pins,
};

struct mv_pinctrl_softc {
        device_t                dev;
        struct syscon           *syscon;

        struct mv_padconf       *padconf;
};

static struct ofw_compat_data compat_data[] = {
        {"marvell,ap806-pinctrl", (uintptr_t)&ap806_padconf},
        {NULL,             0}
};

#define RD4(sc, reg)            SYSCON_READ_4((sc)->syscon, (reg))
#define WR4(sc, reg, val)       SYSCON_WRITE_4((sc)->syscon, (reg), (val))

static void
mv_pinctrl_configure_pin(struct mv_pinctrl_softc *sc, uint32_t pin,
    uint32_t function)
{
        uint32_t offset, shift, reg;

        offset = (pin / PINS_PER_REG) * BITS_PER_PIN;
        shift = (pin % PINS_PER_REG) * BITS_PER_PIN;
        reg = RD4(sc, offset);
        reg &= ~(PINS_MASK << shift);
        reg |= function << shift;
        WR4(sc, offset, reg);
}

static int
mv_pinctrl_configure_pins(device_t dev, phandle_t cfgxref)
{
        struct mv_pinctrl_softc *sc;
        phandle_t node;
        char *function;
        const char **pins;
        int i, pin_num, pin_func, npins;

        sc = device_get_softc(dev);
        node = OF_node_from_xref(cfgxref);

        if (OF_getprop_alloc(node, "marvell,function",
            (void **)&function) == -1)
                return (ENOMEM);

        npins = ofw_bus_string_list_to_array(node, "marvell,pins", &pins);
        if (npins == -1)
                return (ENOMEM);

        for (i = 0; i < npins; i++) {
                for (pin_num = 0; pin_num < sc->padconf->npins; pin_num++) {
                        if (strcmp(pins[i], sc->padconf->pins[pin_num].name) == 0)
                                break;
                }
                if (pin_num == sc->padconf->npins)
                        continue;

                for (pin_func = 0; pin_func < MAX_PIN_FUNC; pin_func++)
                        if (sc->padconf->pins[pin_num].functions[pin_func] &&
                            strcmp(function, sc->padconf->pins[pin_num].functions[pin_func]) == 0)
                                break;

                if (pin_func == MAX_PIN_FUNC)
                        continue;

                mv_pinctrl_configure_pin(sc, pin_num, pin_func);
        }

        OF_prop_free(pins);

        return (0);
}

static int
mv_pinctrl_probe(device_t dev)
{

        if (!ofw_bus_status_okay(dev))
                return (ENXIO);

        if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
                return (ENXIO);

        device_set_desc(dev, "Marvell Pinctrl controller");
        return (BUS_PROBE_DEFAULT);
}

static int
mv_pinctrl_attach(device_t dev)
{
        struct mv_pinctrl_softc *sc;

        sc = device_get_softc(dev);
        sc->dev = dev;
        sc->padconf = (struct mv_padconf *)
            ofw_bus_search_compatible(dev,compat_data)->ocd_data;

        if (SYSCON_GET_HANDLE(sc->dev, &sc->syscon) != 0 ||
            sc->syscon == NULL) {
                device_printf(dev, "cannot get syscon for device\n");
                return (ENXIO);
        }

        fdt_pinctrl_register(dev, "marvell,pins");
        fdt_pinctrl_configure_tree(dev);

        return (0);
}

static int
mv_pinctrl_detach(device_t dev)
{

        return (EBUSY);
}

static device_method_t mv_pinctrl_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         mv_pinctrl_probe),
        DEVMETHOD(device_attach,        mv_pinctrl_attach),
        DEVMETHOD(device_detach,        mv_pinctrl_detach),

        /* fdt_pinctrl interface */
        DEVMETHOD(fdt_pinctrl_configure,mv_pinctrl_configure_pins),

        DEVMETHOD_END
};

static driver_t mv_pinctrl_driver = {
        "mv_pinctrl",
        mv_pinctrl_methods,
        sizeof(struct mv_pinctrl_softc),
};

EARLY_DRIVER_MODULE(mv_pinctrl, simplebus, mv_pinctrl_driver, 0, 0,
    BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);