/*
 *  Interface for OSS sequencer emulation
 *
 *  Copyright (C) 2000 Uros Bizjak <uros@kss-loka.si>
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include "opl3_voice.h"

static int snd_opl3_open_seq_oss(struct snd_seq_oss_arg *arg, void *closure);
static int snd_opl3_close_seq_oss(struct snd_seq_oss_arg *arg);
static int snd_opl3_ioctl_seq_oss(struct snd_seq_oss_arg *arg, unsigned int cmd, unsigned long ioarg);
static int snd_opl3_load_patch_seq_oss(struct snd_seq_oss_arg *arg, int format, const char __user *buf, int offs, int count);
static int snd_opl3_reset_seq_oss(struct snd_seq_oss_arg *arg);

/* */

static inline mm_segment_t snd_enter_user(void)
{
        mm_segment_t fs = get_fs();
        set_fs(get_ds());
        return fs;
}

static inline void snd_leave_user(mm_segment_t fs)
{
        set_fs(fs);
}

/* operators */

extern struct snd_midi_op opl3_ops;

static struct snd_seq_oss_callback oss_callback = {
        .owner =        THIS_MODULE,
        .open =         snd_opl3_open_seq_oss,
        .close =        snd_opl3_close_seq_oss,
        .ioctl =        snd_opl3_ioctl_seq_oss,
        .load_patch =   snd_opl3_load_patch_seq_oss,
        .reset =        snd_opl3_reset_seq_oss,
};

static int snd_opl3_oss_event_input(struct snd_seq_event *ev, int direct,
                                    void *private_data, int atomic, int hop)
{
        struct snd_opl3 *opl3 = private_data;

        if (ev->type != SNDRV_SEQ_EVENT_OSS)
                snd_midi_process_event(&opl3_ops, ev, opl3->oss_chset);
        return 0;
}

/* ------------------------------ */

static void snd_opl3_oss_free_port(void *private_data)
{
        struct snd_opl3 *opl3 = private_data;

        snd_midi_channel_free_set(opl3->oss_chset);
}

static int snd_opl3_oss_create_port(struct snd_opl3 * opl3)
{
        struct snd_seq_port_callback callbacks;
        char name[32];
        int voices, opl_ver;

        voices = (opl3->hardware < OPL3_HW_OPL3) ?
                MAX_OPL2_VOICES : MAX_OPL3_VOICES;
        opl3->oss_chset = snd_midi_channel_alloc_set(voices);
        if (opl3->oss_chset == NULL)
                return -ENOMEM;
        opl3->oss_chset->private_data = opl3;

        memset(&callbacks, 0, sizeof(callbacks));
        callbacks.owner = THIS_MODULE;
        callbacks.event_input = snd_opl3_oss_event_input;
        callbacks.private_free = snd_opl3_oss_free_port;
        callbacks.private_data = opl3;

        opl_ver = (opl3->hardware & OPL3_HW_MASK) >> 8;
        sprintf(name, "OPL%i OSS Port", opl_ver);

        opl3->oss_chset->client = opl3->seq_client;
        opl3->oss_chset->port = snd_seq_event_port_attach(opl3->seq_client, &callbacks,
                                                          SNDRV_SEQ_PORT_CAP_WRITE,
                                                          SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC |
                                                          SNDRV_SEQ_PORT_TYPE_MIDI_GM |
                                                          SNDRV_SEQ_PORT_TYPE_HARDWARE |
                                                          SNDRV_SEQ_PORT_TYPE_SYNTHESIZER,
                                                          voices, voices,
                                                          name);
        if (opl3->oss_chset->port < 0) {
                int port;
                port = opl3->oss_chset->port;
                snd_midi_channel_free_set(opl3->oss_chset);
                return port;
        }
        return 0;
}

/* ------------------------------ */

/* register OSS synth */
void snd_opl3_init_seq_oss(struct snd_opl3 *opl3, char *name)
{
        struct snd_seq_oss_reg *arg;
        struct snd_seq_device *dev;

        if (snd_seq_device_new(opl3->card, 0, SNDRV_SEQ_DEV_ID_OSS,
                               sizeof(struct snd_seq_oss_reg), &dev) < 0)
                return;

        opl3->oss_seq_dev = dev;
        strlcpy(dev->name, name, sizeof(dev->name));
        arg = SNDRV_SEQ_DEVICE_ARGPTR(dev);
        arg->type = SYNTH_TYPE_FM;
        if (opl3->hardware < OPL3_HW_OPL3) {
                arg->subtype = FM_TYPE_ADLIB;
                arg->nvoices = MAX_OPL2_VOICES;
        } else {
                arg->subtype = FM_TYPE_OPL3;
                arg->nvoices = MAX_OPL3_VOICES;
        }
        arg->oper = oss_callback;
        arg->private_data = opl3;

        if (snd_opl3_oss_create_port(opl3)) {
                /* register to OSS synth table */
                snd_device_register(opl3->card, dev);
        }
}

/* unregister */
void snd_opl3_free_seq_oss(struct snd_opl3 *opl3)
{
        if (opl3->oss_seq_dev) {
                /* The instance should have been released in prior */
                opl3->oss_seq_dev = NULL;
        }
}

/* ------------------------------ */

/* open OSS sequencer */
static int snd_opl3_open_seq_oss(struct snd_seq_oss_arg *arg, void *closure)
{
        struct snd_opl3 *opl3 = closure;
        int err;

        if (snd_BUG_ON(!arg))
                return -ENXIO;

        if ((err = snd_opl3_synth_setup(opl3)) < 0)
                return err;

        /* fill the argument data */
        arg->private_data = opl3;
        arg->addr.client = opl3->oss_chset->client;
        arg->addr.port = opl3->oss_chset->port;

        if ((err = snd_opl3_synth_use_inc(opl3)) < 0)
                return err;

        opl3->synth_mode = SNDRV_OPL3_MODE_SYNTH;
        return 0;
}

/* close OSS sequencer */
static int snd_opl3_close_seq_oss(struct snd_seq_oss_arg *arg)
{
        struct snd_opl3 *opl3;

        if (snd_BUG_ON(!arg))
                return -ENXIO;
        opl3 = arg->private_data;

        snd_opl3_synth_cleanup(opl3);

        snd_opl3_synth_use_dec(opl3);
        return 0;
}

/* load patch */

/* from sound_config.h */
#define SBFM_MAXINSTR   256

static int snd_opl3_load_patch_seq_oss(struct snd_seq_oss_arg *arg, int format,
                                       const char __user *buf, int offs, int count)
{
        struct snd_opl3 *opl3;
        struct sbi_instrument sbi;
        char name[32];
        int err, type;

        if (snd_BUG_ON(!arg))
                return -ENXIO;
        opl3 = arg->private_data;

        if (format == FM_PATCH)
                type = FM_PATCH_OPL2;
        else if (format == OPL3_PATCH)
                type = FM_PATCH_OPL3;
        else
                return -EINVAL;

        if (count < (int)sizeof(sbi)) {
                snd_printk(KERN_ERR "FM Error: Patch record too short\n");
                return -EINVAL;
        }
        if (copy_from_user(&sbi, buf, sizeof(sbi)))
                return -EFAULT;

        if (sbi.channel < 0 || sbi.channel >= SBFM_MAXINSTR) {
                snd_printk(KERN_ERR "FM Error: Invalid instrument number %d\n",
                           sbi.channel);
                return -EINVAL;
        }

        memset(name, 0, sizeof(name));
        sprintf(name, "Chan%d", sbi.channel);

        err = snd_opl3_load_patch(opl3, sbi.channel, 127, type, name, NULL,
                                  sbi.operators);
        if (err < 0)
                return err;

        return sizeof(sbi);
}

/* ioctl */
static int snd_opl3_ioctl_seq_oss(struct snd_seq_oss_arg *arg, unsigned int cmd,
                                  unsigned long ioarg)
{
        struct snd_opl3 *opl3;

        if (snd_BUG_ON(!arg))
                return -ENXIO;
        opl3 = arg->private_data;
        switch (cmd) {
                case SNDCTL_FM_LOAD_INSTR:
                        snd_printk(KERN_ERR "OPL3: "
                                   "Obsolete ioctl(SNDCTL_FM_LOAD_INSTR) used. "
                                   "Fix the program.\n");
                        return -EINVAL;

                case SNDCTL_SYNTH_MEMAVL:
                        return 0x7fffffff;

                case SNDCTL_FM_4OP_ENABLE:
                        // handled automatically by OPL instrument type
                        return 0;

                default:
                        return -EINVAL;
        }
        return 0;
}

/* reset device */
static int snd_opl3_reset_seq_oss(struct snd_seq_oss_arg *arg)
{
        struct snd_opl3 *opl3;

        if (snd_BUG_ON(!arg))
                return -ENXIO;
        opl3 = arg->private_data;

        return 0;
}