// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  synth callback routines for Emu10k1
 *
 *  Copyright (C) 2000 Takashi Iwai <tiwai@suse.de>
 */

#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 u32 make_fmmod(struct snd_emux_voice *vp);
static u32 make_fm2frq2(struct snd_emux_voice *vp);
static int get_pitch_shift(struct snd_emux *emu);

/*
 * 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 const 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,
        .get_pitch_shift = get_pitch_shift,
};

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.
 *
 * voice_lock is already held.
 */
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];
        int i;

        emu = hw->synth;

        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];
                        ch = vp->ch;
                        if (ch < 0) {
                                /*
                                dev_warn(emu->card->dev,
                                       "synth_get_voice: ch < 0 (%d) ??", i);
                                */
                                continue;
                        }
                        vp->emu->num_voices--;
                        vp->ch = -1;
                        vp->state = SNDRV_EMUX_ST_OFF;
                        return ch;
                }
        }

        /* not found */
        return -ENOMEM;
}


/*
 * turn off the voice (not terminated)
 */
static void
release_voice(struct snd_emux_voice *vp)
{
        struct snd_emu10k1 *hw;
        
        hw = vp->hw;
        snd_emu10k1_ptr_write_multiple(hw, vp->ch,
                DCYSUSM, (unsigned char)vp->reg.parm.modrelease | DCYSUSM_PHASE1_MASK,
                DCYSUSV, (unsigned char)vp->reg.parm.volrelease | DCYSUSV_PHASE1_MASK | DCYSUSV_CHANNELENABLE_MASK,
                REGLIST_END);
}


/*
 * 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_multiple(hw, vp->ch,
                DCYSUSV, 0,
                VTFT, VTFT_FILTERTARGET_MASK,
                CVCF, CVCF_CURRENTFILTER_MASK,
                PTRX, 0,
                CPF, 0,
                REGLIST_END);
        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_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)
                snd_emu10k1_ptr_write(hw, FMMOD, vp->ch, make_fmmod(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)
                snd_emu10k1_ptr_write(hw, FM2FRQ2, vp->ch, make_fm2frq2(vp));
        if (update & SNDRV_EMUX_UPDATE_Q)
                snd_emu10k1_ptr_write(hw, CCCA_RESONANCE, vp->ch, vp->reg.parm.filterQ);
}


/*
 * 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) - 64 + 3;
                        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, 1, NULL, &hwvoice) < 0)
                                        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;
        bool w_16;
        u32 psst, dsl, map, ccca, vtarget;
        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;
        w_16 = !(vp->reg.sample_mode & SNDRV_SFNT_SAMPLE_8BITS);

        emem = (struct snd_emu10k1_memblk *)vp->block;
        if (emem == NULL)
                return -EINVAL;
        emem->map_locked++;
        if (snd_emu10k1_memblk_map(hw, emem) < 0) {
                /* dev_err(hw->card->devK, "emu: cannot map!\n"); */
                return -ENOMEM;
        }
        mapped_offset = snd_emu10k1_memblk_offset(emem) >> w_16;
        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);
        }

        temp = vp->reg.parm.reverb;
        temp += (int)vp->chan->control[MIDI_CTL_E1_REVERB_DEPTH] * 9 / 10;
        LIMITMAX(temp, 255);
        addr = vp->reg.loopstart;
        psst = (temp << 24) | addr;

        addr = vp->reg.loopend;
        temp = vp->reg.parm.chorus;
        temp += (int)chan->control[MIDI_CTL_E3_CHORUS_DEPTH] * 9 / 10;
        LIMITMAX(temp, 255);
        dsl = (temp << 24) | addr;

        map = (hw->silent_page.addr << hw->address_mode) | (hw->address_mode ? MAP_PTI_MASK1 : MAP_PTI_MASK0);

        addr = vp->reg.start + 64 - 3;
        temp = vp->reg.parm.filterQ;
        ccca = (temp << 28) | addr;
        if (vp->apitch < 0xe400)
                ccca |= CCCA_INTERPROM_0;
        else {
                unsigned int shift = (vp->apitch - 0xe000) >> 10;
                ccca |= shift << 25;
        }
        if (!w_16)
                ccca |= CCCA_8BITSELECT;

        vtarget = (unsigned int)vp->vtarget << 16;

        snd_emu10k1_ptr_write_multiple(hw, ch,
                /* channel to be silent and idle */
                DCYSUSV, 0,
                VTFT, VTFT_FILTERTARGET_MASK,
                CVCF, CVCF_CURRENTFILTER_MASK,
                PTRX, 0,
                CPF, 0,

                /* set pitch offset */
                IP, vp->apitch,

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

                /* cutoff and volume */
                IFATN, (unsigned int)vp->acutoff << 8 | (unsigned char)vp->avol,

                /* modulation envelope heights */
                PEFE, vp->reg.parm.pefe,

                /* lfo1/2 delay */
                LFOVAL1, vp->reg.parm.lfo1delay,
                LFOVAL2, vp->reg.parm.lfo2delay,

                /* lfo1 pitch & cutoff shift */
                FMMOD, make_fmmod(vp),
                /* lfo1 volume & freq */
                TREMFRQ, vp->reg.parm.tremfrq,
                /* lfo2 pitch & freq */
                FM2FRQ2, make_fm2frq2(vp),

                /* reverb and loop start (reverb 8bit, MSB) */
                PSST, psst,

                /* chorus & loop end (chorus 8bit, MSB) */
                DSL, dsl,

                /* clear filter delay memory */
                Z1, 0,
                Z2, 0,

                /* invalidate maps */
                MAPA, map,
                MAPB, map,

                /* Q & current address (Q 4bit value, MSB) */
                CCCA, ccca,

                /* cache */
                CCR, REG_VAL_PUT(CCR_CACHEINVALIDSIZE, 64),

                /* reset volume */
                VTFT, vtarget | vp->ftarget,
                CVCF, vtarget | CVCF_CURRENTFILTER_MASK,

                REGLIST_END);

        hw->voices[ch].dirty = 1;
        return 0;
}

/*
 * Start envelope
 */
static void
trigger_voice(struct snd_emux_voice *vp)
{
        unsigned int 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
        snd_emu10k1_ptr_write_multiple(hw, vp->ch,
                /* set pitch target and pan (volume) */
                PTRX, ptarget | (vp->apan << 8) | vp->aaux,

                /* current pitch and fractional address */
                CPF, ptarget,

                /* enable envelope engine */
                DCYSUSV, vp->reg.parm.voldcysus | DCYSUSV_CHANNELENABLE_MASK,

                REGLIST_END);
}

#define MOD_SENSE 18

/* calculate lfo1 modulation height and cutoff register */
static u32
make_fmmod(struct snd_emux_voice *vp)
{
        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);
        return ((unsigned char)pitch << 8) | cutoff;
}

/* calculate set lfo2 pitch & frequency register */
static u32
make_fm2frq2(struct snd_emux_voice *vp)
{
        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);
        return ((unsigned char)pitch << 8) | freq;
}

static int get_pitch_shift(struct snd_emux *emu)
{
        struct snd_emu10k1 *hw = emu->hw;

        return (hw->card_capabilities->emu_model &&
                        hw->emu1010.word_clock == 44100) ? 0 : -501;
}