/*
 *  synth callback routines for Emu10k1
 *
 *  Copyright (C) 2000 Takashi Iwai <tiwai@suse.de>
 *
 *   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 <linux/export.h>
#include "emu10k1_synth_local.h"
#include <sound/asoundef.h>

/* voice status */
enum {
        V_FREE=0, V_OFF, V_RELEASED, V_PLAYING, V_END
};

/* Keeps track of what we are finding */
struct best_voice {
        unsigned int time;
        int voice;
};

/*
 * prototypes
 */
static void lookup_voices(struct snd_emux *emux, struct snd_emu10k1 *hw,
                          struct best_voice *best, int active_only);
static struct snd_emux_voice *get_voice(struct snd_emux *emux,
                                        struct snd_emux_port *port);
static int start_voice(struct snd_emux_voice *vp);
static void trigger_voice(struct snd_emux_voice *vp);
static void release_voice(struct snd_emux_voice *vp);
static void update_voice(struct snd_emux_voice *vp, int update);
static void terminate_voice(struct snd_emux_voice *vp);
static void free_voice(struct snd_emux_voice *vp);
static void set_fmmod(struct snd_emu10k1 *hw, struct snd_emux_voice *vp);
static void set_fm2frq2(struct snd_emu10k1 *hw, struct snd_emux_voice *vp);
static void set_filterQ(struct snd_emu10k1 *hw, struct snd_emux_voice *vp);

/*
 * Ensure a value is between two points
 * macro evaluates its args more than once, so changed to upper-case.
 */
#define LIMITVALUE(x, a, b) do { if ((x) < (a)) (x) = (a); else if ((x) > (b)) (x) = (b); } while (0)
#define LIMITMAX(x, a) do {if ((x) > (a)) (x) = (a); } while (0)


/*
 * set up operators
 */
static struct snd_emux_operators emu10k1_ops = {
        .owner =        THIS_MODULE,
        .get_voice =    get_voice,
        .prepare =      start_voice,
        .trigger =      trigger_voice,
        .release =      release_voice,
        .update =       update_voice,
        .terminate =    terminate_voice,
        .free_voice =   free_voice,
        .sample_new =   snd_emu10k1_sample_new,
        .sample_free =  snd_emu10k1_sample_free,
};

void
snd_emu10k1_ops_setup(struct snd_emux *emux)
{
        emux->ops = emu10k1_ops;
}


/*
 * get more voice for pcm
 *
 * terminate most inactive voice and give it as a pcm voice.
 */
int
snd_emu10k1_synth_get_voice(struct snd_emu10k1 *hw)
{
        struct snd_emux *emu;
        struct snd_emux_voice *vp;
        struct best_voice best[V_END];
        unsigned long flags;
        int i;

        emu = hw->synth;

        spin_lock_irqsave(&emu->voice_lock, flags);
        lookup_voices(emu, hw, best, 1); /* no OFF voices */
        for (i = 0; i < V_END; i++) {
                if (best[i].voice >= 0) {
                        int ch;
                        vp = &emu->voices[best[i].voice];
                        if ((ch = vp->ch) < 0) {
                                /*
                                printk(KERN_WARNING
                                       "synth_get_voice: ch < 0 (%d) ??", i);
                                */
                                continue;
                        }
                        vp->emu->num_voices--;
                        vp->ch = -1;
                        vp->state = SNDRV_EMUX_ST_OFF;
                        spin_unlock_irqrestore(&emu->voice_lock, flags);
                        return ch;
                }
        }
        spin_unlock_irqrestore(&emu->voice_lock, flags);

        /* not found */
        return -ENOMEM;
}


/*
 * turn off the voice (not terminated)
 */
static void
release_voice(struct snd_emux_voice *vp)
{
        int dcysusv;
        struct snd_emu10k1 *hw;
        
        hw = vp->hw;
        dcysusv = 0x8000 | (unsigned char)vp->reg.parm.modrelease;
        snd_emu10k1_ptr_write(hw, DCYSUSM, vp->ch, dcysusv);
        dcysusv = 0x8000 | (unsigned char)vp->reg.parm.volrelease | DCYSUSV_CHANNELENABLE_MASK;
        snd_emu10k1_ptr_write(hw, DCYSUSV, vp->ch, dcysusv);
}


/*
 * terminate the voice
 */
static void
terminate_voice(struct snd_emux_voice *vp)
{
        struct snd_emu10k1 *hw;
        
        if (snd_BUG_ON(!vp))
                return;
        hw = vp->hw;
        snd_emu10k1_ptr_write(hw, DCYSUSV, vp->ch, 0x807f | DCYSUSV_CHANNELENABLE_MASK);
        if (vp->block) {
                struct snd_emu10k1_memblk *emem;
                emem = (struct snd_emu10k1_memblk *)vp->block;
                if (emem->map_locked > 0)
                        emem->map_locked--;
        }
}

/*
 * release the voice to system
 */
static void
free_voice(struct snd_emux_voice *vp)
{
        struct snd_emu10k1 *hw;
        
        hw = vp->hw;
        /* FIXME: emu10k1_synth is broken. */
        /* This can get called with hw == 0 */
        /* Problem apparent on plug, unplug then plug */
        /* on the Audigy 2 ZS Notebook. */
        if (hw && (vp->ch >= 0)) {
                snd_emu10k1_ptr_write(hw, IFATN, vp->ch, 0xff00);
                snd_emu10k1_ptr_write(hw, DCYSUSV, vp->ch, 0x807f | DCYSUSV_CHANNELENABLE_MASK);
                // snd_emu10k1_ptr_write(hw, DCYSUSV, vp->ch, 0);
                snd_emu10k1_ptr_write(hw, VTFT, vp->ch, 0xffff);
                snd_emu10k1_ptr_write(hw, CVCF, vp->ch, 0xffff);
                snd_emu10k1_voice_free(hw, &hw->voices[vp->ch]);
                vp->emu->num_voices--;
                vp->ch = -1;
        }
}


/*
 * update registers
 */
static void
update_voice(struct snd_emux_voice *vp, int update)
{
        struct snd_emu10k1 *hw;
        
        hw = vp->hw;
        if (update & SNDRV_EMUX_UPDATE_VOLUME)
                snd_emu10k1_ptr_write(hw, IFATN_ATTENUATION, vp->ch, vp->avol);
        if (update & SNDRV_EMUX_UPDATE_PITCH)
                snd_emu10k1_ptr_write(hw, IP, vp->ch, vp->apitch);
        if (update & SNDRV_EMUX_UPDATE_PAN) {
                snd_emu10k1_ptr_write(hw, PTRX_FXSENDAMOUNT_A, vp->ch, vp->apan);
                snd_emu10k1_ptr_write(hw, PTRX_FXSENDAMOUNT_B, vp->ch, vp->aaux);
        }
        if (update & SNDRV_EMUX_UPDATE_FMMOD)
                set_fmmod(hw, vp);
        if (update & SNDRV_EMUX_UPDATE_TREMFREQ)
                snd_emu10k1_ptr_write(hw, TREMFRQ, vp->ch, vp->reg.parm.tremfrq);
        if (update & SNDRV_EMUX_UPDATE_FM2FRQ2)
                set_fm2frq2(hw, vp);
        if (update & SNDRV_EMUX_UPDATE_Q)
                set_filterQ(hw, vp);
}


/*
 * look up voice table - get the best voice in order of preference
 */
/* spinlock held! */
static void
lookup_voices(struct snd_emux *emu, struct snd_emu10k1 *hw,
              struct best_voice *best, int active_only)
{
        struct snd_emux_voice *vp;
        struct best_voice *bp;
        int  i;

        for (i = 0; i < V_END; i++) {
                best[i].time = (unsigned int)-1; /* XXX MAX_?INT really */
                best[i].voice = -1;
        }

        /*
         * Go through them all and get a best one to use.
         * NOTE: could also look at volume and pick the quietest one.
         */
        for (i = 0; i < emu->max_voices; i++) {
                int state, val;

                vp = &emu->voices[i];
                state = vp->state;
                if (state == SNDRV_EMUX_ST_OFF) {
                        if (vp->ch < 0) {
                                if (active_only)
                                        continue;
                                bp = best + V_FREE;
                        } else
                                bp = best + V_OFF;
                }
                else if (state == SNDRV_EMUX_ST_RELEASED ||
                         state == SNDRV_EMUX_ST_PENDING) {
                        bp = best + V_RELEASED;
#if 1
                        val = snd_emu10k1_ptr_read(hw, CVCF_CURRENTVOL, vp->ch);
                        if (! val)
                                bp = best + V_OFF;
#endif
                }
                else if (state == SNDRV_EMUX_ST_STANDBY)
                        continue;
                else if (state & SNDRV_EMUX_ST_ON)
                        bp = best + V_PLAYING;
                else
                        continue;

                /* check if sample is finished playing (non-looping only) */
                if (bp != best + V_OFF && bp != best + V_FREE &&
                    (vp->reg.sample_mode & SNDRV_SFNT_SAMPLE_SINGLESHOT)) {
                        val = snd_emu10k1_ptr_read(hw, CCCA_CURRADDR, vp->ch);
                        if (val >= vp->reg.loopstart)
                                bp = best + V_OFF;
                }

                if (vp->time < bp->time) {
                        bp->time = vp->time;
                        bp->voice = i;
                }
        }
}

/*
 * get an empty voice
 *
 * emu->voice_lock is already held.
 */
static struct snd_emux_voice *
get_voice(struct snd_emux *emu, struct snd_emux_port *port)
{
        struct snd_emu10k1 *hw;
        struct snd_emux_voice *vp;
        struct best_voice best[V_END];
        int i;

        hw = emu->hw;

        lookup_voices(emu, hw, best, 0);
        for (i = 0; i < V_END; i++) {
                if (best[i].voice >= 0) {
                        vp = &emu->voices[best[i].voice];
                        if (vp->ch < 0) {
                                /* allocate a voice */
                                struct snd_emu10k1_voice *hwvoice;
                                if (snd_emu10k1_voice_alloc(hw, EMU10K1_SYNTH, 1, &hwvoice) < 0 || hwvoice == NULL)
                                        continue;
                                vp->ch = hwvoice->number;
                                emu->num_voices++;
                        }
                        return vp;
                }
        }

        /* not found */
        return NULL;
}

/*
 * prepare envelopes and LFOs
 */
static int
start_voice(struct snd_emux_voice *vp)
{
        unsigned int temp;
        int ch;
        unsigned int addr, mapped_offset;
        struct snd_midi_channel *chan;
        struct snd_emu10k1 *hw;
        struct snd_emu10k1_memblk *emem;
        
        hw = vp->hw;
        ch = vp->ch;
        if (snd_BUG_ON(ch < 0))
                return -EINVAL;
        chan = vp->chan;

        emem = (struct snd_emu10k1_memblk *)vp->block;
        if (emem == NULL)
                return -EINVAL;
        emem->map_locked++;
        if (snd_emu10k1_memblk_map(hw, emem) < 0) {
                /* printk(KERN_ERR "emu: cannot map!\n"); */
                return -ENOMEM;
        }
        mapped_offset = snd_emu10k1_memblk_offset(emem) >> 1;
        vp->reg.start += mapped_offset;
        vp->reg.end += mapped_offset;
        vp->reg.loopstart += mapped_offset;
        vp->reg.loopend += mapped_offset;

        /* set channel routing */
        /* A = left(0), B = right(1), C = reverb(c), D = chorus(d) */
        if (hw->audigy) {
                temp = FXBUS_MIDI_LEFT | (FXBUS_MIDI_RIGHT << 8) | 
                        (FXBUS_MIDI_REVERB << 16) | (FXBUS_MIDI_CHORUS << 24);
                snd_emu10k1_ptr_write(hw, A_FXRT1, ch, temp);
        } else {
                temp = (FXBUS_MIDI_LEFT << 16) | (FXBUS_MIDI_RIGHT << 20) | 
                        (FXBUS_MIDI_REVERB << 24) | (FXBUS_MIDI_CHORUS << 28);
                snd_emu10k1_ptr_write(hw, FXRT, ch, temp);
        }

        /* channel to be silent and idle */
        snd_emu10k1_ptr_write(hw, DCYSUSV, ch, 0x0000);
        snd_emu10k1_ptr_write(hw, VTFT, ch, 0x0000FFFF);
        snd_emu10k1_ptr_write(hw, CVCF, ch, 0x0000FFFF);
        snd_emu10k1_ptr_write(hw, PTRX, ch, 0);
        snd_emu10k1_ptr_write(hw, CPF, ch, 0);

        /* set pitch offset */
        snd_emu10k1_ptr_write(hw, IP, vp->ch, vp->apitch);

        /* set envelope parameters */
        snd_emu10k1_ptr_write(hw, ENVVAL, ch, vp->reg.parm.moddelay);
        snd_emu10k1_ptr_write(hw, ATKHLDM, ch, vp->reg.parm.modatkhld);
        snd_emu10k1_ptr_write(hw, DCYSUSM, ch, vp->reg.parm.moddcysus);
        snd_emu10k1_ptr_write(hw, ENVVOL, ch, vp->reg.parm.voldelay);
        snd_emu10k1_ptr_write(hw, ATKHLDV, ch, vp->reg.parm.volatkhld);
        /* decay/sustain parameter for volume envelope is used
           for triggerg the voice */

        /* cutoff and volume */
        temp = (unsigned int)vp->acutoff << 8 | (unsigned char)vp->avol;
        snd_emu10k1_ptr_write(hw, IFATN, vp->ch, temp);

        /* modulation envelope heights */
        snd_emu10k1_ptr_write(hw, PEFE, ch, vp->reg.parm.pefe);

        /* lfo1/2 delay */
        snd_emu10k1_ptr_write(hw, LFOVAL1, ch, vp->reg.parm.lfo1delay);
        snd_emu10k1_ptr_write(hw, LFOVAL2, ch, vp->reg.parm.lfo2delay);

        /* lfo1 pitch & cutoff shift */
        set_fmmod(hw, vp);
        /* lfo1 volume & freq */
        snd_emu10k1_ptr_write(hw, TREMFRQ, vp->ch, vp->reg.parm.tremfrq);
        /* lfo2 pitch & freq */
        set_fm2frq2(hw, vp);

        /* reverb and loop start (reverb 8bit, MSB) */
        temp = vp->reg.parm.reverb;
        temp += (int)vp->chan->control[MIDI_CTL_E1_REVERB_DEPTH] * 9 / 10;
        LIMITMAX(temp, 255);
        addr = vp->reg.loopstart;
        snd_emu10k1_ptr_write(hw, PSST, vp->ch, (temp << 24) | addr);

        /* chorus & loop end (chorus 8bit, MSB) */
        addr = vp->reg.loopend;
        temp = vp->reg.parm.chorus;
        temp += (int)chan->control[MIDI_CTL_E3_CHORUS_DEPTH] * 9 / 10;
        LIMITMAX(temp, 255);
        temp = (temp <<24) | addr;
        snd_emu10k1_ptr_write(hw, DSL, ch, temp);

        /* clear filter delay memory */
        snd_emu10k1_ptr_write(hw, Z1, ch, 0);
        snd_emu10k1_ptr_write(hw, Z2, ch, 0);

        /* invalidate maps */
        temp = (hw->silent_page.addr << 1) | MAP_PTI_MASK;
        snd_emu10k1_ptr_write(hw, MAPA, ch, temp);
        snd_emu10k1_ptr_write(hw, MAPB, ch, temp);
#if 0
        /* cache */
        {
                unsigned int val, sample;
                val = 32;
                if (vp->reg.sample_mode & SNDRV_SFNT_SAMPLE_8BITS)
                        sample = 0x80808080;
                else {
                        sample = 0;
                        val *= 2;
                }

                /* cache */
                snd_emu10k1_ptr_write(hw, CCR, ch, 0x1c << 16);
                snd_emu10k1_ptr_write(hw, CDE, ch, sample);
                snd_emu10k1_ptr_write(hw, CDF, ch, sample);

                /* invalidate maps */
                temp = ((unsigned int)hw->silent_page.addr << 1) | MAP_PTI_MASK;
                snd_emu10k1_ptr_write(hw, MAPA, ch, temp);
                snd_emu10k1_ptr_write(hw, MAPB, ch, temp);
                
                /* fill cache */
                val -= 4;
                val <<= 25;
                val |= 0x1c << 16;
                snd_emu10k1_ptr_write(hw, CCR, ch, val);
        }
#endif

        /* Q & current address (Q 4bit value, MSB) */
        addr = vp->reg.start;
        temp = vp->reg.parm.filterQ;
        temp = (temp<<28) | addr;
        if (vp->apitch < 0xe400)
                temp |= CCCA_INTERPROM_0;
        else {
                unsigned int shift = (vp->apitch - 0xe000) >> 10;
                temp |= shift << 25;
        }
        if (vp->reg.sample_mode & SNDRV_SFNT_SAMPLE_8BITS)
                temp |= CCCA_8BITSELECT;
        snd_emu10k1_ptr_write(hw, CCCA, ch, temp);

        /* reset volume */
        temp = (unsigned int)vp->vtarget << 16;
        snd_emu10k1_ptr_write(hw, VTFT, ch, temp | vp->ftarget);
        snd_emu10k1_ptr_write(hw, CVCF, ch, temp | 0xff00);
        return 0;
}

/*
 * Start envelope
 */
static void
trigger_voice(struct snd_emux_voice *vp)
{
        unsigned int temp, ptarget;
        struct snd_emu10k1 *hw;
        struct snd_emu10k1_memblk *emem;
        
        hw = vp->hw;

        emem = (struct snd_emu10k1_memblk *)vp->block;
        if (! emem || emem->mapped_page < 0)
                return; /* not mapped */

#if 0
        ptarget = (unsigned int)vp->ptarget << 16;
#else
        ptarget = IP_TO_CP(vp->apitch);
#endif
        /* set pitch target and pan (volume) */
        temp = ptarget | (vp->apan << 8) | vp->aaux;
        snd_emu10k1_ptr_write(hw, PTRX, vp->ch, temp);

        /* pitch target */
        snd_emu10k1_ptr_write(hw, CPF, vp->ch, ptarget);

        /* trigger voice */
        snd_emu10k1_ptr_write(hw, DCYSUSV, vp->ch, vp->reg.parm.voldcysus|DCYSUSV_CHANNELENABLE_MASK);
}

#define MOD_SENSE 18

/* set lfo1 modulation height and cutoff */
static void
set_fmmod(struct snd_emu10k1 *hw, struct snd_emux_voice *vp)
{
        unsigned short fmmod;
        short pitch;
        unsigned char cutoff;
        int modulation;

        pitch = (char)(vp->reg.parm.fmmod>>8);
        cutoff = (vp->reg.parm.fmmod & 0xff);
        modulation = vp->chan->gm_modulation + vp->chan->midi_pressure;
        pitch += (MOD_SENSE * modulation) / 1200;
        LIMITVALUE(pitch, -128, 127);
        fmmod = ((unsigned char)pitch<<8) | cutoff;
        snd_emu10k1_ptr_write(hw, FMMOD, vp->ch, fmmod);
}

/* set lfo2 pitch & frequency */
static void
set_fm2frq2(struct snd_emu10k1 *hw, struct snd_emux_voice *vp)
{
        unsigned short fm2frq2;
        short pitch;
        unsigned char freq;
        int modulation;

        pitch = (char)(vp->reg.parm.fm2frq2>>8);
        freq = vp->reg.parm.fm2frq2 & 0xff;
        modulation = vp->chan->gm_modulation + vp->chan->midi_pressure;
        pitch += (MOD_SENSE * modulation) / 1200;
        LIMITVALUE(pitch, -128, 127);
        fm2frq2 = ((unsigned char)pitch<<8) | freq;
        snd_emu10k1_ptr_write(hw, FM2FRQ2, vp->ch, fm2frq2);
}

/* set filterQ */
static void
set_filterQ(struct snd_emu10k1 *hw, struct snd_emux_voice *vp)
{
        unsigned int val;
        val = snd_emu10k1_ptr_read(hw, CCCA, vp->ch) & ~CCCA_RESONANCE;
        val |= (vp->reg.parm.filterQ << 28);
        snd_emu10k1_ptr_write(hw, CCCA, vp->ch, val);
}