/*-
 * SPDX-License-Identifier: BSD-2-Clause

 * Copyright (c) 2015-2018 Tai-hwa Liang <avatar@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/param.h>
#include <sys/types.h>
#include <sys/bus.h>
#include <machine/bus.h>
#include <sys/rman.h>
#include <sys/systm.h>
#include <sys/kobj.h>
#include <sys/lock.h>
#include <sys/mutex.h>

#ifdef HAVE_KERNEL_OPTION_HEADERS
#include "opt_snd.h"
#endif

#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>

#include <dev/sound/pcm/sound.h>

#include <dev/sound/midi/midi.h>
#include <dev/sound/midi/mpu401.h>

#include <dev/sound/pci/csareg.h>
#include <dev/sound/pci/csavar.h>

#include "mpufoi_if.h"

/* pulled from mpu401.c */
#define MPU_DATAPORT    0
#define MPU_CMDPORT     1
#define MPU_STATPORT    1
#define MPU_RESET       0xff
#define MPU_UART        0x3f
#define MPU_ACK         0xfe
#define MPU_STATMASK    0xc0
#define MPU_OUTPUTBUSY  0x40
#define MPU_INPUTBUSY   0x80

/* device private data */
struct csa_midi_softc {
        /* hardware resources */
        int             io_rid;         /* io rid */
        struct resource *io;            /* io */

        struct mtx      mtx;
        device_t        dev;
        struct mpu401   *mpu;
        mpu401_intr_t   *mpu_intr;
        int             mflags;         /* MIDI flags */
};

static struct kobj_class csamidi_mpu_class;

static u_int32_t
csamidi_readio(struct csa_midi_softc *scp, u_long offset)
{
        if (offset < BA0_AC97_RESET)
                return bus_space_read_4(rman_get_bustag(scp->io), rman_get_bushandle(scp->io), offset) & 0xffffffff;
        else
                return (0);
}

static void
csamidi_writeio(struct csa_midi_softc *scp, u_long offset, u_int32_t data)
{
        if (offset < BA0_AC97_RESET)
                bus_space_write_4(rman_get_bustag(scp->io), rman_get_bushandle(scp->io), offset, data);
}

static void
csamidi_midi_intr(void *arg)
{
        struct csa_midi_softc *scp = (struct csa_midi_softc *)arg;

        if (scp->mpu_intr)
                (scp->mpu_intr)(scp->mpu);
}

static unsigned char
csamidi_mread(struct mpu401 *arg __unused, void *cookie, int reg)
{
        struct csa_midi_softc *scp = cookie;
        unsigned int rc;
        unsigned int uart_stat;

        rc = 0;
        /* hacks to convert hardware status to MPU compatible ones */
        switch (reg) {
        case MPU_STATPORT:
                uart_stat = csamidi_readio(scp, BA0_MIDSR);
                if (uart_stat & MIDSR_TBF)
                        rc |= MPU_OUTPUTBUSY;   /* Tx buffer full */
                if (uart_stat & MIDSR_RBE)
                        rc |= MPU_INPUTBUSY;
                break;
        case MPU_DATAPORT:
                rc = csamidi_readio(scp, BA0_MIDRP);
                break;
        default:
                printf("csamidi_mread: unknown register %d\n", reg);
                break;
        }
        return (rc);
}

static void
csamidi_mwrite(struct mpu401 *arg __unused, void *cookie, int reg, unsigned char b)
{
        struct csa_midi_softc *scp = cookie;
        unsigned int val;

        switch (reg) {
        case MPU_CMDPORT:
                switch (b)
                {
                case MPU_RESET:
                        /* preserve current operation mode */
                        val = csamidi_readio(scp, BA0_MIDCR);
                        /* reset the MIDI port */
                        csamidi_writeio(scp, BA0_MIDCR, MIDCR_MRST);
                        csamidi_writeio(scp, BA0_MIDCR, MIDCR_MLB);
                        csamidi_writeio(scp, BA0_MIDCR, 0x00);
                        /* restore previous operation mode */
                        csamidi_writeio(scp, BA0_MIDCR, val);
                        break;
                case MPU_UART:
                        /* switch to UART mode, no-op */
                default:
                        break;
                }
                break;
        case MPU_DATAPORT:
                /* put the MIDI databyte in the write port */
                csamidi_writeio(scp, BA0_MIDWP, b);
                break;
        default:
                printf("csamidi_mwrite: unknown register %d\n", reg);
                break;
        }
}

static int
csamidi_muninit(struct mpu401 *arg __unused, void *cookie)
{
        struct csa_midi_softc *scp = cookie;

        mtx_lock(&scp->mtx);
        scp->mpu_intr = NULL;
        mtx_unlock(&scp->mtx);

        return (0);
}

static int
midicsa_probe(device_t dev)
{
        struct sndcard_func *func;

        /* The parent device has already been probed. */

        func = device_get_ivars(dev);
        if (func == NULL || func->func != SCF_MIDI)
                return (ENXIO);

        device_set_desc(dev, "CS461x MIDI");
        return (0);
}

static int
midicsa_attach(device_t dev)
{
        struct csa_midi_softc *scp;
        int rc = ENXIO;

        scp = device_get_softc(dev);

        bzero(scp, sizeof(struct csa_midi_softc));
        scp->dev = dev;

        /* allocate the required resources */
        scp->io_rid = PCIR_BAR(0);
        scp->io = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
            &scp->io_rid, RF_ACTIVE);
        if (scp->io == NULL)
                goto err0;

        /* init the fake MPU401 interface. */
        scp->mpu = mpu401_init(&csamidi_mpu_class, scp, csamidi_midi_intr,
            &scp->mpu_intr);
        if (scp->mpu == NULL) {
                rc = ENOMEM;
                goto err1;
        }

        mtx_init(&scp->mtx, device_get_nameunit(dev), "csamidi softc",
            MTX_DEF);

        /* reset the MIDI port */
        csamidi_writeio(scp, BA0_MIDCR, MIDCR_MRST);
        /* MIDI transmit enable, no interrupt */
        csamidi_writeio(scp, BA0_MIDCR, MIDCR_TXE | MIDCR_RXE);
        csamidi_writeio(scp, BA0_HICR, HICR_IEV | HICR_CHGM);

        return (0);
err1:
        bus_release_resource(dev, SYS_RES_MEMORY, scp->io_rid, scp->io);
        scp->io = NULL;
err0:
        return (rc);
}

static int
midicsa_detach(device_t dev)
{
        struct csa_midi_softc *scp;
        int rc = 0;

        scp = device_get_softc(dev);
        rc = mpu401_uninit(scp->mpu);
        if (rc)
                return (rc);
        if (scp->io != NULL) {
                bus_release_resource(dev, SYS_RES_MEMORY, scp->io_rid,
                    scp->io);
                scp->io = NULL;
        }
        mtx_destroy(&scp->mtx);
        return (rc);
}

static kobj_method_t csamidi_mpu_methods[] = {
        KOBJMETHOD(mpufoi_read, csamidi_mread),
        KOBJMETHOD(mpufoi_write, csamidi_mwrite),
        KOBJMETHOD(mpufoi_uninit, csamidi_muninit),
        KOBJMETHOD_END
};

static DEFINE_CLASS(csamidi_mpu, csamidi_mpu_methods, 0);

static device_method_t midicsa_methods[] = {
        DEVMETHOD(device_probe, midicsa_probe),
        DEVMETHOD(device_attach, midicsa_attach),
        DEVMETHOD(device_detach, midicsa_detach),

        DEVMETHOD_END
};

static driver_t midicsa_driver = {
        "midi",
        midicsa_methods,
        sizeof(struct csa_midi_softc),
};
DRIVER_MODULE(snd_csa_midi, csa, midicsa_driver, 0, 0);
MODULE_DEPEND(snd_csa_midi, snd_csa, 1, 1, 1);
MODULE_DEPEND(snd_csa_midi, sound, SOUND_MINVER, SOUND_PREFVER, SOUND_MAXVER);
MODULE_VERSION(snd_csa_midi, 1);