/* $NetBSD: admgpio.c,v 1.6 2021/08/07 16:18:58 thorpej Exp $ */

/*-
* Copyright (c) 2007 David Young.  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 ``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
* 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>

__KERNEL_RCSID(0, "$NetBSD: admgpio.c,v 1.6 2021/08/07 16:18:58 thorpej Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/gpio.h>
#include <sys/kernel.h> /* for hz */

#include <sys/bus.h>

#include <dev/gpio/gpiovar.h>

#include <mips/adm5120/include/adm5120reg.h>
#include <mips/adm5120/include/adm5120var.h>
#include <mips/adm5120/include/adm5120_mainbusvar.h>

static inline uint32_t
admgpio_read(struct mainbus_softc *sc)
{
       return bus_space_read_4(sc->sc_obiot, sc->sc_gpioh, ADM5120_GPIO0);
}

static inline void
admgpio_write(struct mainbus_softc *sc, uint32_t val)
{
       bus_space_write_4(sc->sc_obiot, sc->sc_gpioh, ADM5120_GPIO0, val);
}

static void
admgpio_pin_ctl(void *cookie, int pin, int flags)
{
       struct mainbus_softc *sc = cookie;
       uint32_t gpio0, mask;

       KASSERT(flags == GPIO_PIN_INPUT || flags == GPIO_PIN_OUTPUT);

       mask = __SHIFTIN(1 << pin, ADM5120_GPIO0_OE);
       gpio0 = admgpio_read(sc);

       if (flags == GPIO_PIN_OUTPUT)
               admgpio_write(sc, gpio0 | mask);
       else
               admgpio_write(sc, gpio0 & ~mask);
}

static int
admgpio_pin_read(void *cookie, int pin)
{
       struct mainbus_softc *sc = cookie;
       uint32_t gpio0, mask;

       KASSERT(pin >= 0 && pin < 8);

       if (sc->sc_pins[pin].pin_flags == GPIO_PIN_INPUT)
               mask = __SHIFTIN(1 << pin, ADM5120_GPIO0_IV);
       else
               mask = __SHIFTIN(1 << pin, ADM5120_GPIO0_OV);

       gpio0 = admgpio_read(sc);

       return ((gpio0 & mask) != 0) ? GPIO_PIN_HIGH : GPIO_PIN_LOW;
}

static void
admgpio_pin_write(void *cookie, int pin, int value)
{
       struct mainbus_softc *sc = cookie;
       uint32_t gpio0, mask;

       KASSERT(pin >= 0 && pin < 8);

       mask = __SHIFTIN(1 << pin, ADM5120_GPIO0_OV);
       gpio0 = admgpio_read(sc);

       admgpio_write(sc,
           (value == GPIO_PIN_HIGH) ? (gpio0 | mask) : (gpio0 & ~mask));
}

device_t
admgpio_attach(struct mainbus_softc *sc)
{
       int pin;
       uint32_t oe;
       struct gpiobus_attach_args gba;

       oe = __SHIFTOUT(admgpio_read(sc), ADM5120_GPIO0_OE);

       for (pin = 0; pin < __arraycount(sc->sc_pins); pin++) {
               sc->sc_pins[pin].pin_num = pin;
               sc->sc_pins[pin].pin_caps = GPIO_PIN_INPUT | GPIO_PIN_OUTPUT;

               if ((oe & (1 << pin)) != 0)
                       sc->sc_pins[pin].pin_flags = GPIO_PIN_OUTPUT;
               else
                       sc->sc_pins[pin].pin_flags = GPIO_PIN_INPUT;

               sc->sc_pins[pin].pin_state = admgpio_pin_read(sc, pin);
       }

       sc->sc_gp.gp_cookie = sc;
       sc->sc_gp.gp_pin_read = admgpio_pin_read;
       sc->sc_gp.gp_pin_write = admgpio_pin_write;
       sc->sc_gp.gp_pin_ctl = admgpio_pin_ctl;

       gba.gba_gc = &sc->sc_gp;
       gba.gba_pins = &sc->sc_pins[0];
       gba.gba_npins = __arraycount(sc->sc_pins);

       /* Attach GPIO framework */
       return config_found(sc->sc_dev, &gba, gpiobus_print,
           CFARGS(.iattr = "gpiobus"));
}