/* $NetBSD: pl050.c,v 1.2 2017/06/06 00:26:16 jmcneill Exp $ */

/*-
* Copyright (c) 2017 Jared McNeill <[email protected]>
* 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: pl050.c,v 1.2 2017/06/06 00:26:16 jmcneill Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/kmem.h>
#include <sys/bus.h>

#include <dev/pckbport/pckbportvar.h>

#include <dev/ic/pl050var.h>

#define KMICR           0x00
#define  KMIRXINTREN    __BIT(4)
#define  KMIEN          __BIT(2)
#define KMISTAT         0x04
#define  TXEMPTY        __BIT(6)
#define  RXFULL         __BIT(4)
#define KMIDATA         0x08
#define KMICLKDIV       0x0c
#define KMIIR           0x10
#define  KMIRXINTR      __BIT(0)

#define PLKMI_READ(sc, reg)             \
       bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg))
#define PLKMI_WRITE(sc, reg, val)       \
       bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val))

static int
plkmi_wait(struct plkmi_softc *sc, uint32_t mask, bool set)
{
       int timeout = 1000;

       const uint32_t val = (set ? mask : 0);

       while (timeout-- > 0) {
               const uint32_t stat = PLKMI_READ(sc, KMISTAT);
               if ((stat & mask) == val)
                       return 0;
               delay(10);
       }

       return ETIMEDOUT;
}

static int
plkmi_xt_translation(void *priv, pckbport_slot_t port, int on)
{
       if (on)
               return 0;
       return 1;
}

static int
plkmi_send_devcmd(void *priv, pckbport_slot_t slot, u_char byte)
{
       struct plkmi_softc * const sc = priv;

       if (plkmi_wait(sc, TXEMPTY, true))
               return 0;

       PLKMI_WRITE(sc, KMIDATA, byte & 0xff);

       return 1;
}

static int
plkmi_poll_data1(void *priv, pckbport_slot_t slot)
{
       struct plkmi_softc * const sc = priv;

       if (plkmi_wait(sc, RXFULL, true))
               return -1;

       return PLKMI_READ(sc, KMIDATA) & 0xff;
}

static void
plkmi_slot_enable(void *priv, pckbport_slot_t slot, int on)
{
       struct plkmi_softc * const sc = priv;
       uint32_t cr;

       cr = PLKMI_READ(sc, KMICR);
       if (on)
               cr |= KMIEN;
       else
               cr &= ~KMIEN;
       PLKMI_WRITE(sc, KMICR, cr);
}

static void
plkmi_set_poll(void *priv, pckbport_slot_t slot, int on)
{
       struct plkmi_softc * const sc = priv;
       uint32_t cr;

       cr = PLKMI_READ(sc, KMICR);
       if (on)
               cr &= ~KMIRXINTREN;
       else
               cr |= KMIRXINTREN;
       PLKMI_WRITE(sc, KMICR, cr);
}

static void
plkmi_intr_establish(void *priv, pckbport_slot_t slot)
{
       /* XXX */
       plkmi_set_poll(priv, slot, 0);
}

static struct pckbport_accessops plkmi_ops = {
       .t_xt_translation = plkmi_xt_translation,
       .t_send_devcmd = plkmi_send_devcmd,
       .t_poll_data1 = plkmi_poll_data1,
       .t_slot_enable = plkmi_slot_enable,
       .t_set_poll = plkmi_set_poll,
       .t_intr_establish = plkmi_intr_establish,
};

void
plkmi_attach(struct plkmi_softc *sc)
{
       aprint_naive("\n");
       aprint_normal(": PS2 controller\n");

       sc->sc_pt = pckbport_attach(sc, &plkmi_ops);
       sc->sc_slot = -1;

       PLKMI_WRITE(sc, KMICR, KMIEN);

       for (int slot = 0; slot < PCKBPORT_NSLOTS; slot++)
               if (pckbport_attach_slot(sc->sc_dev, sc->sc_pt, slot)) {
                       sc->sc_slot = slot;
                       break;
               }

       if (sc->sc_slot == PCKBPORT_KBD_SLOT)
               pckbport_cnattach(sc, &plkmi_ops, sc->sc_slot);
}

int
plkmi_intr(void *priv)
{
       struct plkmi_softc * const sc = priv;
       int handled = 0;

       if (sc->sc_slot == -1)
               return 0;

       const uint32_t stat = PLKMI_READ(sc, KMISTAT);
       if (stat & RXFULL) {
               const uint32_t val = PLKMI_READ(sc, KMIDATA);
               pckbportintr(sc->sc_pt, sc->sc_slot, val & 0xff);
               handled = 1;
       }

       return handled;
}