// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *                   Lee Revell <rlrevell@joe-job.com>
 *                   James Courtier-Dutton <James@superbug.co.uk>
 *                   Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
 *                   Creative Labs, Inc.
 *
 *  Routines for control of EMU10K1 chips / PCM routines
 */

#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/init.h>
#include <sound/core.h>
#include <sound/emu10k1.h>

static void snd_emu10k1_pcm_interrupt(struct snd_emu10k1 *emu,
                                      struct snd_emu10k1_voice *voice)
{
        struct snd_emu10k1_pcm *epcm;

        epcm = voice->epcm;
        if (!epcm)
                return;
        if (epcm->substream == NULL)
                return;
#if 0
        dev_dbg(emu->card->dev,
                "IRQ: position = 0x%x, period = 0x%x, size = 0x%x\n",
                        epcm->substream->runtime->hw->pointer(emu, epcm->substream),
                        snd_pcm_lib_period_bytes(epcm->substream),
                        snd_pcm_lib_buffer_bytes(epcm->substream));
#endif
        snd_pcm_period_elapsed(epcm->substream);
}

static void snd_emu10k1_pcm_ac97adc_interrupt(struct snd_emu10k1 *emu,
                                              unsigned int status)
{
#if 0
        if (status & IPR_ADCBUFHALFFULL) {
                if (emu->pcm_capture_substream->runtime->mode == SNDRV_PCM_MODE_FRAME)
                        return;
        }
#endif
        snd_pcm_period_elapsed(emu->pcm_capture_substream);
}

static void snd_emu10k1_pcm_ac97mic_interrupt(struct snd_emu10k1 *emu,
                                              unsigned int status)
{
#if 0
        if (status & IPR_MICBUFHALFFULL) {
                if (emu->pcm_capture_mic_substream->runtime->mode == SNDRV_PCM_MODE_FRAME)
                        return;
        }
#endif
        snd_pcm_period_elapsed(emu->pcm_capture_mic_substream);
}

static void snd_emu10k1_pcm_efx_interrupt(struct snd_emu10k1 *emu,
                                          unsigned int status)
{
#if 0
        if (status & IPR_EFXBUFHALFFULL) {
                if (emu->pcm_capture_efx_substream->runtime->mode == SNDRV_PCM_MODE_FRAME)
                        return;
        }
#endif
        snd_pcm_period_elapsed(emu->pcm_capture_efx_substream);
}        

static void snd_emu10k1_pcm_free_voices(struct snd_emu10k1_pcm *epcm)
{
        for (unsigned i = 0; i < ARRAY_SIZE(epcm->voices); i++) {
                if (epcm->voices[i]) {
                        snd_emu10k1_voice_free(epcm->emu, epcm->voices[i]);
                        epcm->voices[i] = NULL;
                }
        }
}

static int snd_emu10k1_pcm_channel_alloc(struct snd_emu10k1_pcm *epcm,
                                         int type, int count, int channels)
{
        int err;

        snd_emu10k1_pcm_free_voices(epcm);

        err = snd_emu10k1_voice_alloc(epcm->emu,
                                      type, count, channels,
                                      epcm, &epcm->voices[0]);
        if (err < 0)
                return err;

        if (epcm->extra == NULL) {
                // The hardware supports only (half-)loop interrupts, so to support an
                // arbitrary number of periods per buffer, we use an extra voice with a
                // period-sized loop as the interrupt source. Additionally, the interrupt
                // timing of the hardware is "suboptimal" and needs some compensation.
                err = snd_emu10k1_voice_alloc(epcm->emu,
                                              type + 1, 1, 1,
                                              epcm, &epcm->extra);
                if (err < 0) {
                        /*
                        dev_dbg(emu->card->dev, "pcm_channel_alloc: "
                               "failed extra: voices=%d, frame=%d\n",
                               voices, frame);
                        */
                        snd_emu10k1_pcm_free_voices(epcm);
                        return err;
                }
                epcm->extra->interrupt = snd_emu10k1_pcm_interrupt;
        }

        return 0;
}

// Primes 2-7 and 2^n multiples thereof, up to 16.
static const unsigned int efx_capture_channels[] = {
        1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16
};

static const struct snd_pcm_hw_constraint_list hw_constraints_efx_capture_channels = {
        .count = ARRAY_SIZE(efx_capture_channels),
        .list = efx_capture_channels,
        .mask = 0
};

static const unsigned int capture_buffer_sizes[31] = {
        384,    448,    512,    640,
        384*2,  448*2,  512*2,  640*2,
        384*4,  448*4,  512*4,  640*4,
        384*8,  448*8,  512*8,  640*8,
        384*16, 448*16, 512*16, 640*16,
        384*32, 448*32, 512*32, 640*32,
        384*64, 448*64, 512*64, 640*64,
        384*128,448*128,512*128
};

static const struct snd_pcm_hw_constraint_list hw_constraints_capture_buffer_sizes = {
        .count = 31,
        .list = capture_buffer_sizes,
        .mask = 0
};

static unsigned int snd_emu10k1_capture_rate_reg(unsigned int rate)
{
        switch (rate) {
        case 8000:      return ADCCR_SAMPLERATE_8;
        case 11025:     return ADCCR_SAMPLERATE_11;
        case 16000:     return ADCCR_SAMPLERATE_16;
        case 22050:     return ADCCR_SAMPLERATE_22;
        case 24000:     return ADCCR_SAMPLERATE_24;
        case 32000:     return ADCCR_SAMPLERATE_32;
        case 44100:     return ADCCR_SAMPLERATE_44;
        case 48000:     return ADCCR_SAMPLERATE_48;
        default:
                        snd_BUG();
                        return ADCCR_SAMPLERATE_8;
        }
}

static unsigned int snd_emu10k1_audigy_capture_rate_reg(unsigned int rate)
{
        switch (rate) {
        case 8000:      return A_ADCCR_SAMPLERATE_8;
        case 11025:     return A_ADCCR_SAMPLERATE_11;
        case 12000:     return A_ADCCR_SAMPLERATE_12;
        case 16000:     return ADCCR_SAMPLERATE_16;
        case 22050:     return ADCCR_SAMPLERATE_22;
        case 24000:     return ADCCR_SAMPLERATE_24;
        case 32000:     return ADCCR_SAMPLERATE_32;
        case 44100:     return ADCCR_SAMPLERATE_44;
        case 48000:     return ADCCR_SAMPLERATE_48;
        default:
                        snd_BUG();
                        return A_ADCCR_SAMPLERATE_8;
        }
}

static void snd_emu10k1_constrain_capture_rates(struct snd_emu10k1 *emu,
                                                struct snd_pcm_runtime *runtime)
{
        if (emu->card_capabilities->emu_model &&
            emu->emu1010.word_clock == 44100) {
                runtime->hw.rates = SNDRV_PCM_RATE_11025 | \
                                    SNDRV_PCM_RATE_22050 | \
                                    SNDRV_PCM_RATE_44100;
                runtime->hw.rate_min = 11025;
                runtime->hw.rate_max = 44100;
        } else if (emu->audigy) {
                runtime->hw.rates = SNDRV_PCM_RATE_8000_48000 |
                                    SNDRV_PCM_RATE_12000 |
                                    SNDRV_PCM_RATE_24000;
        }
}

static void snd_emu1010_constrain_efx_rate(struct snd_emu10k1 *emu,
                                           struct snd_pcm_runtime *runtime)
{
        int rate;

        rate = emu->emu1010.word_clock;
        runtime->hw.rate_min = runtime->hw.rate_max = rate;
        runtime->hw.rates = snd_pcm_rate_to_rate_bit(rate);
}

static unsigned int emu10k1_calc_pitch_target(unsigned int rate)
{
        unsigned int pitch_target;

        pitch_target = (rate << 8) / 375;
        pitch_target = (pitch_target >> 1) + (pitch_target & 1);
        return pitch_target;
}

#define PITCH_48000 0x00004000
#define PITCH_96000 0x00008000
#define PITCH_85000 0x00007155
#define PITCH_80726 0x00006ba2
#define PITCH_67882 0x00005a82
#define PITCH_57081 0x00004c1c

static unsigned int emu10k1_select_interprom(unsigned int pitch_target)
{
        if (pitch_target == PITCH_48000)
                return CCCA_INTERPROM_0;
        else if (pitch_target < PITCH_48000)
                return CCCA_INTERPROM_1;
        else if (pitch_target >= PITCH_96000)
                return CCCA_INTERPROM_0;
        else if (pitch_target >= PITCH_85000)
                return CCCA_INTERPROM_6;
        else if (pitch_target >= PITCH_80726)
                return CCCA_INTERPROM_5;
        else if (pitch_target >= PITCH_67882)
                return CCCA_INTERPROM_4;
        else if (pitch_target >= PITCH_57081)
                return CCCA_INTERPROM_3;
        else  
                return CCCA_INTERPROM_2;
}

static u16 emu10k1_send_target_from_amount(u8 amount)
{
        static const u8 shifts[8] = { 4, 4, 5, 6, 7, 8, 9, 10 };
        static const u16 offsets[8] = { 0, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000 };
        u8 exp;

        if (amount == 0xff)
                return 0xffff;
        exp = amount >> 5;
        return ((amount & 0x1f) << shifts[exp]) + offsets[exp];
}

static void snd_emu10k1_pcm_init_voice(struct snd_emu10k1 *emu,
                                       struct snd_emu10k1_voice *evoice,
                                       bool w_16, bool stereo,
                                       unsigned int start_addr,
                                       unsigned int end_addr,
                                       const unsigned char *send_routing,
                                       const unsigned char *send_amount)
{
        unsigned int silent_page;
        int voice;

        voice = evoice->number;

        silent_page = ((unsigned int)emu->silent_page.addr << emu->address_mode) |
                      (emu->address_mode ? MAP_PTI_MASK1 : MAP_PTI_MASK0);
        snd_emu10k1_ptr_write_multiple(emu, voice,
                // Not really necessary for the slave, but it doesn't hurt
                CPF, stereo ? CPF_STEREO_MASK : 0,
                // Assumption that PT is already 0 so no harm overwriting
                PTRX, (send_amount[0] << 8) | send_amount[1],
                // Stereo slaves don't need to have the addresses set, but it doesn't hurt
                DSL, end_addr | (send_amount[3] << 24),
                PSST, start_addr | (send_amount[2] << 24),
                CCCA, emu10k1_select_interprom(evoice->epcm->pitch_target) |
                      (w_16 ? 0 : CCCA_8BITSELECT),
                // Clear filter delay memory
                Z1, 0,
                Z2, 0,
                // Invalidate maps
                MAPA, silent_page,
                MAPB, silent_page,
                // Disable filter (in conjunction with CCCA_RESONANCE == 0)
                VTFT, VTFT_FILTERTARGET_MASK,
                CVCF, CVCF_CURRENTFILTER_MASK,
                REGLIST_END);
        // Setup routing
        if (emu->audigy) {
                snd_emu10k1_ptr_write_multiple(emu, voice,
                        A_FXRT1, snd_emu10k1_compose_audigy_fxrt1(send_routing),
                        A_FXRT2, snd_emu10k1_compose_audigy_fxrt2(send_routing),
                        A_SENDAMOUNTS, snd_emu10k1_compose_audigy_sendamounts(send_amount),
                        REGLIST_END);
                for (int i = 0; i < 4; i++) {
                        u32 aml = emu10k1_send_target_from_amount(send_amount[2 * i]);
                        u32 amh = emu10k1_send_target_from_amount(send_amount[2 * i + 1]);
                        snd_emu10k1_ptr_write(emu, A_CSBA + i, voice, (amh << 16) | aml);
                }
        } else {
                snd_emu10k1_ptr_write(emu, FXRT, voice,
                                      snd_emu10k1_compose_send_routing(send_routing));
        }

        emu->voices[voice].dirty = 1;
}

static void snd_emu10k1_pcm_init_voices(struct snd_emu10k1 *emu,
                                        struct snd_emu10k1_voice *evoice,
                                        bool w_16, bool stereo,
                                        unsigned int start_addr,
                                        unsigned int end_addr,
                                        struct snd_emu10k1_pcm_mixer *mix)
{
        guard(spinlock_irq)(&emu->reg_lock);
        snd_emu10k1_pcm_init_voice(emu, evoice, w_16, stereo,
                                   start_addr, end_addr,
                                   &mix->send_routing[stereo][0],
                                   &mix->send_volume[stereo][0]);
        if (stereo)
                snd_emu10k1_pcm_init_voice(emu, evoice + 1, w_16, true,
                                           start_addr, end_addr,
                                           &mix->send_routing[2][0],
                                           &mix->send_volume[2][0]);
}

static void snd_emu10k1_pcm_init_extra_voice(struct snd_emu10k1 *emu,
                                             struct snd_emu10k1_voice *evoice,
                                             bool w_16,
                                             unsigned int start_addr,
                                             unsigned int end_addr)
{
        static const unsigned char send_routing[8] = { 0, 1, 2, 3, 4, 5, 6, 7 };
        static const unsigned char send_amount[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };

        snd_emu10k1_pcm_init_voice(emu, evoice, w_16, false,
                                   start_addr, end_addr,
                                   send_routing, send_amount);
}

static int snd_emu10k1_playback_hw_params(struct snd_pcm_substream *substream,
                                          struct snd_pcm_hw_params *hw_params)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_pcm *epcm = runtime->private_data;
        size_t alloc_size;
        int type, channels, count;
        int err;

        if (epcm->type == PLAYBACK_EMUVOICE) {
                type = EMU10K1_PCM;
                channels = 1;
                count = params_channels(hw_params);
        } else {
                type = EMU10K1_EFX;
                channels = params_channels(hw_params);
                count = 1;
        }
        err = snd_emu10k1_pcm_channel_alloc(epcm, type, count, channels);
        if (err < 0)
                return err;

        alloc_size = params_buffer_bytes(hw_params);
        if (emu->iommu_workaround)
                alloc_size += EMUPAGESIZE;
        err = snd_pcm_lib_malloc_pages(substream, alloc_size);
        if (err < 0)
                return err;
        if (emu->iommu_workaround && runtime->dma_bytes >= EMUPAGESIZE)
                runtime->dma_bytes -= EMUPAGESIZE;
        if (err > 0) {  /* change */
                int mapped;
                if (epcm->memblk != NULL)
                        snd_emu10k1_free_pages(emu, epcm->memblk);
                epcm->memblk = snd_emu10k1_alloc_pages(emu, substream);
                epcm->start_addr = 0;
                if (! epcm->memblk)
                        return -ENOMEM;
                mapped = ((struct snd_emu10k1_memblk *)epcm->memblk)->mapped_page;
                if (mapped < 0)
                        return -ENOMEM;
                epcm->start_addr = mapped << PAGE_SHIFT;
        }
        return 0;
}

static int snd_emu10k1_playback_hw_free(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_pcm *epcm;

        if (runtime->private_data == NULL)
                return 0;
        epcm = runtime->private_data;
        if (epcm->extra) {
                snd_emu10k1_voice_free(epcm->emu, epcm->extra);
                epcm->extra = NULL;
        }
        snd_emu10k1_pcm_free_voices(epcm);
        if (epcm->memblk) {
                snd_emu10k1_free_pages(emu, epcm->memblk);
                epcm->memblk = NULL;
                epcm->start_addr = 0;
        }
        snd_pcm_lib_free_pages(substream);
        return 0;
}

static int snd_emu10k1_playback_prepare(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_pcm *epcm = runtime->private_data;
        bool w_16 = snd_pcm_format_width(runtime->format) == 16;
        bool stereo = runtime->channels == 2;
        unsigned int start_addr, end_addr;
        unsigned int rate;

        rate = runtime->rate;
        if (emu->card_capabilities->emu_model &&
            emu->emu1010.word_clock == 44100)
                rate = rate * 480 / 441;
        epcm->pitch_target = emu10k1_calc_pitch_target(rate);

        start_addr = epcm->start_addr >> w_16;
        end_addr = start_addr + runtime->period_size;
        snd_emu10k1_pcm_init_extra_voice(emu, epcm->extra, w_16,
                                         start_addr, end_addr);
        start_addr >>= stereo;
        epcm->ccca_start_addr = start_addr;
        end_addr = start_addr + runtime->buffer_size;
        snd_emu10k1_pcm_init_voices(emu, epcm->voices[0], w_16, stereo,
                                    start_addr, end_addr,
                                    &emu->pcm_mixer[substream->number]);

        return 0;
}

static int snd_emu10k1_efx_playback_prepare(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_pcm *epcm = runtime->private_data;
        unsigned int start_addr;
        unsigned int extra_size, channel_size;
        unsigned int i;

        epcm->pitch_target = PITCH_48000;

        start_addr = epcm->start_addr >> 1;  // 16-bit voices

        extra_size = runtime->period_size;
        channel_size = runtime->buffer_size;

        snd_emu10k1_pcm_init_extra_voice(emu, epcm->extra, true,
                                         start_addr, start_addr + extra_size);

        epcm->ccca_start_addr = start_addr;
        for (i = 0; i < runtime->channels; i++) {
                snd_emu10k1_pcm_init_voices(emu, epcm->voices[i], true, false,
                                            start_addr, start_addr + channel_size,
                                            &emu->efx_pcm_mixer[i]);
                start_addr += channel_size;
        }

        return 0;
}

static const struct snd_pcm_hardware snd_emu10k1_efx_playback =
{
        .info =                 (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_NONINTERLEAVED |
                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
                                 SNDRV_PCM_INFO_RESUME |
                                 SNDRV_PCM_INFO_MMAP_VALID | SNDRV_PCM_INFO_PAUSE),
        .formats =              SNDRV_PCM_FMTBIT_S16_LE,
        .rates =                SNDRV_PCM_RATE_48000,
        .rate_min =             48000,
        .rate_max =             48000,
        .channels_min =         1,
        .channels_max =         NUM_EFX_PLAYBACK,
        .buffer_bytes_max =     (128*1024),
        .period_bytes_max =     (128*1024),
        .periods_min =          2,
        .periods_max =          1024,
        .fifo_size =            0,
};

static int snd_emu10k1_capture_prepare(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_pcm *epcm = runtime->private_data;
        int idx;

        /* zeroing the buffer size will stop capture */
        snd_emu10k1_ptr_write(emu, epcm->capture_bs_reg, 0, 0);
        switch (epcm->type) {
        case CAPTURE_AC97ADC:
                snd_emu10k1_ptr_write(emu, ADCCR, 0, 0);
                break;
        case CAPTURE_EFX:
                if (emu->card_capabilities->emu_model) {
                        // The upper 32 16-bit capture voices, two for each of the 16 32-bit channels.
                        // The lower voices are occupied by A_EXTOUT_*_CAP*.
                        epcm->capture_cr_val = 0;
                        epcm->capture_cr_val2 = 0xffffffff >> (32 - runtime->channels * 2);
                }
                if (emu->audigy) {
                        snd_emu10k1_ptr_write_multiple(emu, 0,
                                A_FXWC1, 0,
                                A_FXWC2, 0,
                                REGLIST_END);
                } else
                        snd_emu10k1_ptr_write(emu, FXWC, 0, 0);
                break;
        default:
                break;
        }       
        snd_emu10k1_ptr_write(emu, epcm->capture_ba_reg, 0, runtime->dma_addr);
        epcm->capture_bufsize = snd_pcm_lib_buffer_bytes(substream);
        epcm->capture_bs_val = 0;
        for (idx = 0; idx < 31; idx++) {
                if (capture_buffer_sizes[idx] == epcm->capture_bufsize) {
                        epcm->capture_bs_val = idx + 1;
                        break;
                }
        }
        if (epcm->capture_bs_val == 0) {
                snd_BUG();
                epcm->capture_bs_val++;
        }
        if (epcm->type == CAPTURE_AC97ADC) {
                unsigned rate = runtime->rate;
                if (!(runtime->hw.rates & SNDRV_PCM_RATE_48000))
                        rate = rate * 480 / 441;

                epcm->capture_cr_val = emu->audigy ? A_ADCCR_LCHANENABLE : ADCCR_LCHANENABLE;
                if (runtime->channels > 1)
                        epcm->capture_cr_val |= emu->audigy ? A_ADCCR_RCHANENABLE : ADCCR_RCHANENABLE;
                epcm->capture_cr_val |= emu->audigy ?
                        snd_emu10k1_audigy_capture_rate_reg(rate) :
                        snd_emu10k1_capture_rate_reg(rate);
        }
        return 0;
}

static void snd_emu10k1_playback_fill_cache(struct snd_emu10k1 *emu,
                                            unsigned voice,
                                            u32 sample, bool stereo)
{
        u32 ccr;

        // We assume that the cache is resting at this point (i.e.,
        // CCR_CACHEINVALIDSIZE is very small).

        // Clear leading frames. For simplicitly, this does too much,
        // except for 16-bit stereo. And the interpolator will actually
        // access them at all only when we're pitch-shifting.
        for (int i = 0; i < 3; i++)
                snd_emu10k1_ptr_write(emu, CD0 + i, voice, sample);

        // Fill cache
        ccr = (64 - 3) << REG_SHIFT(CCR_CACHEINVALIDSIZE);
        if (stereo) {
                // The engine goes haywire if CCR_READADDRESS is out of sync
                snd_emu10k1_ptr_write(emu, CCR, voice + 1, ccr);
        }
        snd_emu10k1_ptr_write(emu, CCR, voice, ccr);
}

static void snd_emu10k1_playback_prepare_voices(struct snd_emu10k1 *emu,
                                                struct snd_emu10k1_pcm *epcm,
                                                bool w_16, bool stereo,
                                                int channels)
{
        struct snd_pcm_substream *substream = epcm->substream;
        struct snd_pcm_runtime *runtime = substream->runtime;
        unsigned eloop_start = epcm->start_addr >> w_16;
        unsigned loop_start = eloop_start >> stereo;
        unsigned eloop_size = runtime->period_size;
        unsigned loop_size = runtime->buffer_size;
        u32 sample = w_16 ? 0 : 0x80808080;

        // To make the playback actually start at the 1st frame,
        // we need to compensate for two circumstances:
        // - The actual position is delayed by the cache size (64 frames)
        // - The interpolator is centered around the 4th frame
        loop_start += (epcm->resume_pos + 64 - 3) % loop_size;
        for (int i = 0; i < channels; i++) {
                unsigned voice = epcm->voices[i]->number;
                snd_emu10k1_ptr_write(emu, CCCA_CURRADDR, voice, loop_start);
                loop_start += loop_size;
                snd_emu10k1_playback_fill_cache(emu, voice, sample, stereo);
        }

        // The interrupt is triggered when CCCA_CURRADDR (CA) wraps around,
        // which is ahead of the actual playback position, so the interrupt
        // source needs to be delayed.
        //
        // In principle, this wouldn't need to be the cache's entire size - in
        // practice, CCR_CACHEINVALIDSIZE (CIS) > `fetch threshold` has never
        // been observed, and assuming 40 _bytes_ should be safe.
        //
        // The cache fills are somewhat random, which makes it impossible to
        // align them with the interrupts. This makes a non-delayed interrupt
        // source not practical, as the interrupt handler would have to wait
        // for (CA - CIS) >= period_boundary for every channel in the stream.
        //
        // This is why all other (open) drivers for these chips use timer-based
        // interrupts.
        //
        eloop_start += (epcm->resume_pos + eloop_size - 3) % eloop_size;
        snd_emu10k1_ptr_write(emu, CCCA_CURRADDR, epcm->extra->number, eloop_start);

        // It takes a moment until the cache fills complete,
        // but the unmuting takes long enough for that.
}

static void snd_emu10k1_playback_commit_volume(struct snd_emu10k1 *emu,
                                               struct snd_emu10k1_voice *evoice,
                                               unsigned int vattn)
{
        snd_emu10k1_ptr_write_multiple(emu, evoice->number,
                VTFT, vattn | VTFT_FILTERTARGET_MASK,
                CVCF, vattn | CVCF_CURRENTFILTER_MASK,
                REGLIST_END);
}

static void snd_emu10k1_playback_unmute_voice(struct snd_emu10k1 *emu,
                                              struct snd_emu10k1_voice *evoice,
                                              bool stereo, bool master,
                                              struct snd_emu10k1_pcm_mixer *mix)
{
        unsigned int vattn;
        unsigned int tmp;

        tmp = stereo ? (master ? 1 : 2) : 0;
        vattn = mix->attn[tmp] << 16;
        snd_emu10k1_playback_commit_volume(emu, evoice, vattn);
}       

static void snd_emu10k1_playback_unmute_voices(struct snd_emu10k1 *emu,
                                               struct snd_emu10k1_voice *evoice,
                                               bool stereo,
                                               struct snd_emu10k1_pcm_mixer *mix)
{
        snd_emu10k1_playback_unmute_voice(emu, evoice, stereo, true, mix);
        if (stereo)
                snd_emu10k1_playback_unmute_voice(emu, evoice + 1, true, false, mix);
}

static void snd_emu10k1_playback_mute_voice(struct snd_emu10k1 *emu,
                                            struct snd_emu10k1_voice *evoice)
{
        snd_emu10k1_playback_commit_volume(emu, evoice, 0);
}

static void snd_emu10k1_playback_mute_voices(struct snd_emu10k1 *emu,
                                             struct snd_emu10k1_voice *evoice,
                                             bool stereo)
{
        snd_emu10k1_playback_mute_voice(emu, evoice);
        if (stereo)
                snd_emu10k1_playback_mute_voice(emu, evoice + 1);
}

static void snd_emu10k1_playback_commit_pitch(struct snd_emu10k1 *emu,
                                              u32 voice, u32 pitch_target)
{
        u32 ptrx = snd_emu10k1_ptr_read(emu, PTRX, voice);
        u32 cpf = snd_emu10k1_ptr_read(emu, CPF, voice);
        snd_emu10k1_ptr_write_multiple(emu, voice,
                PTRX, (ptrx & ~PTRX_PITCHTARGET_MASK) | pitch_target,
                CPF, (cpf & ~(CPF_CURRENTPITCH_MASK | CPF_FRACADDRESS_MASK)) | pitch_target,
                REGLIST_END);
}

static void snd_emu10k1_playback_trigger_voice(struct snd_emu10k1 *emu,
                                               struct snd_emu10k1_voice *evoice)
{
        unsigned int voice;

        voice = evoice->number;
        snd_emu10k1_playback_commit_pitch(emu, voice, evoice->epcm->pitch_target << 16);
}

static void snd_emu10k1_playback_stop_voice(struct snd_emu10k1 *emu,
                                            struct snd_emu10k1_voice *evoice)
{
        unsigned int voice;

        voice = evoice->number;
        snd_emu10k1_playback_commit_pitch(emu, voice, 0);
}

static void snd_emu10k1_playback_set_running(struct snd_emu10k1 *emu,
                                             struct snd_emu10k1_pcm *epcm)
{
        epcm->running = 1;
        snd_emu10k1_voice_intr_enable(emu, epcm->extra->number);
}

static void snd_emu10k1_playback_set_stopped(struct snd_emu10k1 *emu,
                                              struct snd_emu10k1_pcm *epcm)
{
        snd_emu10k1_voice_intr_disable(emu, epcm->extra->number);
        epcm->running = 0;
}

static int snd_emu10k1_playback_trigger(struct snd_pcm_substream *substream,
                                        int cmd)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_pcm *epcm = runtime->private_data;
        struct snd_emu10k1_pcm_mixer *mix;
        bool w_16 = snd_pcm_format_width(runtime->format) == 16;
        bool stereo = runtime->channels == 2;

        /*
        dev_dbg(emu->card->dev,
                "trigger - emu10k1 = 0x%x, cmd = %i, pointer = %i\n",
               (int)emu, cmd, substream->ops->pointer(substream))
        */
        guard(spinlock)(&emu->reg_lock);
        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
                snd_emu10k1_playback_prepare_voices(emu, epcm, w_16, stereo, 1);
                fallthrough;
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
        case SNDRV_PCM_TRIGGER_RESUME:
                mix = &emu->pcm_mixer[substream->number];
                snd_emu10k1_playback_unmute_voices(emu, epcm->voices[0], stereo, mix);
                snd_emu10k1_playback_set_running(emu, epcm);
                snd_emu10k1_playback_trigger_voice(emu, epcm->voices[0]);
                snd_emu10k1_playback_trigger_voice(emu, epcm->extra);
                break;
        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
        case SNDRV_PCM_TRIGGER_SUSPEND:
                snd_emu10k1_playback_stop_voice(emu, epcm->voices[0]);
                snd_emu10k1_playback_stop_voice(emu, epcm->extra);
                snd_emu10k1_playback_set_stopped(emu, epcm);
                snd_emu10k1_playback_mute_voices(emu, epcm->voices[0], stereo);
                break;
        default:
                return -EINVAL;
        }
        return 0;
}

static int snd_emu10k1_capture_trigger(struct snd_pcm_substream *substream,
                                       int cmd)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_pcm *epcm = runtime->private_data;

        guard(spinlock)(&emu->reg_lock);
        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_RESUME:
                /* hmm this should cause full and half full interrupt to be raised? */
                outl(epcm->capture_ipr, emu->port + IPR);
                snd_emu10k1_intr_enable(emu, epcm->capture_inte);
                /*
                dev_dbg(emu->card->dev, "adccr = 0x%x, adcbs = 0x%x\n",
                       epcm->adccr, epcm->adcbs);
                */
                switch (epcm->type) {
                case CAPTURE_AC97ADC:
                        snd_emu10k1_ptr_write(emu, ADCCR, 0, epcm->capture_cr_val);
                        break;
                case CAPTURE_EFX:
                        if (emu->audigy) {
                                snd_emu10k1_ptr_write_multiple(emu, 0,
                                        A_FXWC1, epcm->capture_cr_val,
                                        A_FXWC2, epcm->capture_cr_val2,
                                        REGLIST_END);
                                dev_dbg(emu->card->dev,
                                        "cr_val=0x%x, cr_val2=0x%x\n",
                                        epcm->capture_cr_val,
                                        epcm->capture_cr_val2);
                        } else
                                snd_emu10k1_ptr_write(emu, FXWC, 0, epcm->capture_cr_val);
                        break;
                default:        
                        break;
                }
                snd_emu10k1_ptr_write(emu, epcm->capture_bs_reg, 0, epcm->capture_bs_val);
                epcm->running = 1;
                epcm->first_ptr = 1;
                break;
        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_SUSPEND:
                epcm->running = 0;
                snd_emu10k1_intr_disable(emu, epcm->capture_inte);
                outl(epcm->capture_ipr, emu->port + IPR);
                snd_emu10k1_ptr_write(emu, epcm->capture_bs_reg, 0, 0);
                switch (epcm->type) {
                case CAPTURE_AC97ADC:
                        snd_emu10k1_ptr_write(emu, ADCCR, 0, 0);
                        break;
                case CAPTURE_EFX:
                        if (emu->audigy) {
                                snd_emu10k1_ptr_write_multiple(emu, 0,
                                        A_FXWC1, 0,
                                        A_FXWC2, 0,
                                        REGLIST_END);
                        } else
                                snd_emu10k1_ptr_write(emu, FXWC, 0, 0);
                        break;
                default:
                        break;
                }
                break;
        default:
                return -EINVAL;
        }
        return 0;
}

static snd_pcm_uframes_t snd_emu10k1_playback_pointer(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_pcm *epcm = runtime->private_data;
        int ptr;

        if (!epcm->running)
                return 0;

        ptr = snd_emu10k1_ptr_read(emu, CCCA, epcm->voices[0]->number) & 0x00ffffff;
        ptr -= epcm->ccca_start_addr;

        // This is the size of the whole cache minus the interpolator read-ahead,
        // which leads us to the actual playback position.
        //
        // The cache is constantly kept mostly filled, so in principle we could
        // return a more advanced position representing how far the hardware has
        // already read the buffer, and set runtime->delay accordingly. However,
        // this would be slightly different for every channel (and remarkably slow
        // to obtain), so only a fixed worst-case value would be practical.
        //
        ptr -= 64 - 3;
        if (ptr < 0)
                ptr += runtime->buffer_size;

        /*
        dev_dbg(emu->card->dev,
               "ptr = 0x%lx, buffer_size = 0x%lx, period_size = 0x%lx\n",
               (long)ptr, (long)runtime->buffer_size,
               (long)runtime->period_size);
        */
        return ptr;
}

static u64 snd_emu10k1_efx_playback_voice_mask(struct snd_emu10k1_pcm *epcm,
                                               int channels)
{
        u64 mask = 0;

        for (int i = 0; i < channels; i++) {
                int voice = epcm->voices[i]->number;
                mask |= 1ULL << voice;
        }
        return mask;
}

static void snd_emu10k1_efx_playback_freeze_voices(struct snd_emu10k1 *emu,
                                                   struct snd_emu10k1_pcm *epcm,
                                                   int channels)
{
        for (int i = 0; i < channels; i++) {
                int voice = epcm->voices[i]->number;
                snd_emu10k1_ptr_write(emu, CPF_STOP, voice, 1);
                snd_emu10k1_playback_commit_pitch(emu, voice, PITCH_48000 << 16);
        }
}

static void snd_emu10k1_efx_playback_unmute_voices(struct snd_emu10k1 *emu,
                                                   struct snd_emu10k1_pcm *epcm,
                                                   int channels)
{
        for (int i = 0; i < channels; i++)
                snd_emu10k1_playback_unmute_voice(emu, epcm->voices[i], false, true,
                                                  &emu->efx_pcm_mixer[i]);
}

static void snd_emu10k1_efx_playback_stop_voices(struct snd_emu10k1 *emu,
                                                 struct snd_emu10k1_pcm *epcm,
                                                 int channels)
{
        for (int i = 0; i < channels; i++)
                snd_emu10k1_playback_stop_voice(emu, epcm->voices[i]);
        snd_emu10k1_playback_set_stopped(emu, epcm);

        for (int i = 0; i < channels; i++)
                snd_emu10k1_playback_mute_voice(emu, epcm->voices[i]);
}

static int snd_emu10k1_efx_playback_trigger(struct snd_pcm_substream *substream,
                                        int cmd)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_pcm *epcm = runtime->private_data;
        u64 mask;
        int result = 0;

        guard(spinlock)(&emu->reg_lock);
        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
        case SNDRV_PCM_TRIGGER_RESUME:
                mask = snd_emu10k1_efx_playback_voice_mask(
                                epcm, runtime->channels);
                for (int i = 0; i < 10; i++) {
                        // Note that the freeze is not interruptible, so we make no
                        // effort to reset the bits outside the error handling here.
                        snd_emu10k1_voice_set_loop_stop_multiple(emu, mask);
                        snd_emu10k1_efx_playback_freeze_voices(
                                        emu, epcm, runtime->channels);
                        snd_emu10k1_playback_prepare_voices(
                                        emu, epcm, true, false, runtime->channels);

                        // It might seem to make more sense to unmute the voices only after
                        // they have been started, to potentially avoid torturing the speakers
                        // if something goes wrong. However, we cannot unmute atomically,
                        // which means that we'd get some mild artifacts in the regular case.
                        snd_emu10k1_efx_playback_unmute_voices(emu, epcm, runtime->channels);

                        snd_emu10k1_playback_set_running(emu, epcm);
                        result = snd_emu10k1_voice_clear_loop_stop_multiple_atomic(emu, mask);
                        if (result == 0) {
                                // The extra voice is allowed to lag a bit
                                snd_emu10k1_playback_trigger_voice(emu, epcm->extra);
                                return 0;
                        }

                        snd_emu10k1_efx_playback_stop_voices(
                                        emu, epcm, runtime->channels);

                        if (result != -EAGAIN)
                                break;
                        // The sync start can legitimately fail due to NMIs, etc.
                }
                snd_emu10k1_voice_clear_loop_stop_multiple(emu, mask);
                break;
        case SNDRV_PCM_TRIGGER_SUSPEND:
        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                snd_emu10k1_playback_stop_voice(emu, epcm->extra);
                snd_emu10k1_efx_playback_stop_voices(
                                emu, epcm, runtime->channels);

                epcm->resume_pos = snd_emu10k1_playback_pointer(substream);
                break;
        default:
                return -EINVAL;
        }
        return result;
}


static snd_pcm_uframes_t snd_emu10k1_capture_pointer(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_pcm *epcm = runtime->private_data;
        unsigned int ptr;

        if (!epcm->running)
                return 0;
        if (epcm->first_ptr) {
                udelay(50);     /* hack, it takes awhile until capture is started */
                epcm->first_ptr = 0;
        }
        ptr = snd_emu10k1_ptr_read(emu, epcm->capture_idx_reg, 0) & 0x0000ffff;
        return bytes_to_frames(runtime, ptr);
}

/*
 *  Playback support device description
 */

static const struct snd_pcm_hardware snd_emu10k1_playback =
{
        .info =                 (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
                                 SNDRV_PCM_INFO_RESUME |
                                 SNDRV_PCM_INFO_MMAP_VALID | SNDRV_PCM_INFO_PAUSE),
        .formats =              SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE,
        .rates =                SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_96000,
        .rate_min =             4000,
        .rate_max =             96000,
        .channels_min =         1,
        .channels_max =         2,
        .buffer_bytes_max =     (128*1024),
        .period_bytes_max =     (128*1024),
        .periods_min =          2,
        .periods_max =          1024,
        .fifo_size =            0,
};

/*
 *  Capture support device description
 */

static const struct snd_pcm_hardware snd_emu10k1_capture =
{
        .info =                 (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
                                 SNDRV_PCM_INFO_RESUME |
                                 SNDRV_PCM_INFO_MMAP_VALID),
        .formats =              SNDRV_PCM_FMTBIT_S16_LE,
        .rates =                SNDRV_PCM_RATE_8000_48000 | SNDRV_PCM_RATE_24000,
        .rate_min =             8000,
        .rate_max =             48000,
        .channels_min =         1,
        .channels_max =         2,
        .buffer_bytes_max =     (64*1024),
        .period_bytes_min =     384,
        .period_bytes_max =     (64*1024),
        .periods_min =          2,
        .periods_max =          2,
        .fifo_size =            0,
};

static const struct snd_pcm_hardware snd_emu10k1_capture_efx =
{
        .info =                 (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
                                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
                                 SNDRV_PCM_INFO_RESUME |
                                 SNDRV_PCM_INFO_MMAP_VALID),
        .formats =              SNDRV_PCM_FMTBIT_S16_LE,
        .rates =                SNDRV_PCM_RATE_48000,
        .rate_min =             48000,
        .rate_max =             48000,
        .channels_min =         1,
        .channels_max =         16,
        .buffer_bytes_max =     (64*1024),
        .period_bytes_min =     384,
        .period_bytes_max =     (64*1024),
        .periods_min =          2,
        .periods_max =          2,
        .fifo_size =            0,
};

/*
 *
 */

static void snd_emu10k1_pcm_mixer_notify1(struct snd_emu10k1 *emu, struct snd_kcontrol *kctl, int idx, int activate)
{
        struct snd_ctl_elem_id id;

        if (! kctl)
                return;
        if (activate)
                kctl->vd[idx].access &= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE;
        else
                kctl->vd[idx].access |= SNDRV_CTL_ELEM_ACCESS_INACTIVE;
        snd_ctl_notify(emu->card, SNDRV_CTL_EVENT_MASK_VALUE |
                       SNDRV_CTL_EVENT_MASK_INFO,
                       snd_ctl_build_ioff(&id, kctl, idx));
}

static void snd_emu10k1_pcm_mixer_notify(struct snd_emu10k1 *emu, int idx, int activate)
{
        snd_emu10k1_pcm_mixer_notify1(emu, emu->ctl_send_routing, idx, activate);
        snd_emu10k1_pcm_mixer_notify1(emu, emu->ctl_send_volume, idx, activate);
        snd_emu10k1_pcm_mixer_notify1(emu, emu->ctl_attn, idx, activate);
}

static void snd_emu10k1_pcm_efx_mixer_notify(struct snd_emu10k1 *emu, int idx, int activate)
{
        snd_emu10k1_pcm_mixer_notify1(emu, emu->ctl_efx_send_routing, idx, activate);
        snd_emu10k1_pcm_mixer_notify1(emu, emu->ctl_efx_send_volume, idx, activate);
        snd_emu10k1_pcm_mixer_notify1(emu, emu->ctl_efx_attn, idx, activate);
}

static void snd_emu10k1_pcm_free_substream(struct snd_pcm_runtime *runtime)
{
        kfree(runtime->private_data);
}

static int snd_emu10k1_efx_playback_close(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_pcm_mixer *mix;
        int i;

        for (i = 0; i < NUM_EFX_PLAYBACK; i++) {
                mix = &emu->efx_pcm_mixer[i];
                mix->epcm = NULL;
                snd_emu10k1_pcm_efx_mixer_notify(emu, i, 0);
        }
        return 0;
}

static int snd_emu10k1_playback_set_constraints(struct snd_pcm_runtime *runtime)
{
        int err;

        // The buffer size must be a multiple of the period size, to avoid a
        // mismatch between the extra voice and the regular voices.
        err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
        if (err < 0)
                return err;
        // The hardware is typically the cache's size of 64 frames ahead.
        // Leave enough time for actually filling up the buffer.
        err = snd_pcm_hw_constraint_minmax(
                        runtime, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 128, UINT_MAX);
        return err;
}

static int snd_emu10k1_efx_playback_open(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_pcm *epcm;
        struct snd_emu10k1_pcm_mixer *mix;
        struct snd_pcm_runtime *runtime = substream->runtime;
        int i, j, err;

        epcm = kzalloc_obj(*epcm);
        if (epcm == NULL)
                return -ENOMEM;
        epcm->emu = emu;
        epcm->type = PLAYBACK_EFX;
        epcm->substream = substream;
        
        runtime->private_data = epcm;
        runtime->private_free = snd_emu10k1_pcm_free_substream;
        runtime->hw = snd_emu10k1_efx_playback;
        if (emu->card_capabilities->emu_model)
                snd_emu1010_constrain_efx_rate(emu, runtime);
        err = snd_emu10k1_playback_set_constraints(runtime);
        if (err < 0) {
                kfree(epcm);
                return err;
        }

        for (i = 0; i < NUM_EFX_PLAYBACK; i++) {
                mix = &emu->efx_pcm_mixer[i];
                for (j = 0; j < 8; j++)
                        mix->send_routing[0][j] = i + j;
                memset(&mix->send_volume, 0, sizeof(mix->send_volume));
                mix->send_volume[0][0] = 255;
                mix->attn[0] = 0x8000;
                mix->epcm = epcm;
                snd_emu10k1_pcm_efx_mixer_notify(emu, i, 1);
        }
        return 0;
}

static int snd_emu10k1_playback_open(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_pcm *epcm;
        struct snd_emu10k1_pcm_mixer *mix;
        struct snd_pcm_runtime *runtime = substream->runtime;
        int i, err, sample_rate;

        epcm = kzalloc_obj(*epcm);
        if (epcm == NULL)
                return -ENOMEM;
        epcm->emu = emu;
        epcm->type = PLAYBACK_EMUVOICE;
        epcm->substream = substream;
        runtime->private_data = epcm;
        runtime->private_free = snd_emu10k1_pcm_free_substream;
        runtime->hw = snd_emu10k1_playback;
        err = snd_emu10k1_playback_set_constraints(runtime);
        if (err < 0) {
                kfree(epcm);
                return err;
        }
        if (emu->card_capabilities->emu_model)
                sample_rate = emu->emu1010.word_clock;
        else
                sample_rate = 48000;
        err = snd_pcm_hw_rule_noresample(runtime, sample_rate);
        if (err < 0) {
                kfree(epcm);
                return err;
        }
        mix = &emu->pcm_mixer[substream->number];
        for (i = 0; i < 8; i++)
                mix->send_routing[0][i] = mix->send_routing[1][i] = mix->send_routing[2][i] = i;
        memset(&mix->send_volume, 0, sizeof(mix->send_volume));
        mix->send_volume[0][0] = mix->send_volume[0][1] =
        mix->send_volume[1][0] = mix->send_volume[2][1] = 255;
        mix->attn[0] = mix->attn[1] = mix->attn[2] = 0x8000;
        mix->epcm = epcm;
        snd_emu10k1_pcm_mixer_notify(emu, substream->number, 1);
        return 0;
}

static int snd_emu10k1_playback_close(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_pcm_mixer *mix = &emu->pcm_mixer[substream->number];

        mix->epcm = NULL;
        snd_emu10k1_pcm_mixer_notify(emu, substream->number, 0);
        return 0;
}

static int snd_emu10k1_capture_open(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_pcm *epcm;

        epcm = kzalloc_obj(*epcm);
        if (epcm == NULL)
                return -ENOMEM;
        epcm->emu = emu;
        epcm->type = CAPTURE_AC97ADC;
        epcm->substream = substream;
        epcm->capture_ipr = IPR_ADCBUFFULL|IPR_ADCBUFHALFFULL;
        epcm->capture_inte = INTE_ADCBUFENABLE;
        epcm->capture_ba_reg = ADCBA;
        epcm->capture_bs_reg = ADCBS;
        epcm->capture_idx_reg = emu->audigy ? A_ADCIDX : ADCIDX;
        runtime->private_data = epcm;
        runtime->private_free = snd_emu10k1_pcm_free_substream;
        runtime->hw = snd_emu10k1_capture;
        snd_emu10k1_constrain_capture_rates(emu, runtime);
        snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
                                   &hw_constraints_capture_buffer_sizes);
        emu->capture_interrupt = snd_emu10k1_pcm_ac97adc_interrupt;
        emu->pcm_capture_substream = substream;
        return 0;
}

static int snd_emu10k1_capture_close(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);

        emu->capture_interrupt = NULL;
        emu->pcm_capture_substream = NULL;
        return 0;
}

static int snd_emu10k1_capture_mic_open(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_pcm *epcm;
        struct snd_pcm_runtime *runtime = substream->runtime;

        epcm = kzalloc_obj(*epcm);
        if (epcm == NULL)
                return -ENOMEM;
        epcm->emu = emu;
        epcm->type = CAPTURE_AC97MIC;
        epcm->substream = substream;
        epcm->capture_ipr = IPR_MICBUFFULL|IPR_MICBUFHALFFULL;
        epcm->capture_inte = INTE_MICBUFENABLE;
        epcm->capture_ba_reg = MICBA;
        epcm->capture_bs_reg = MICBS;
        epcm->capture_idx_reg = emu->audigy ? A_MICIDX : MICIDX;
        substream->runtime->private_data = epcm;
        substream->runtime->private_free = snd_emu10k1_pcm_free_substream;
        runtime->hw = snd_emu10k1_capture;
        runtime->hw.rates = SNDRV_PCM_RATE_8000;
        runtime->hw.rate_min = runtime->hw.rate_max = 8000;
        snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
                                   &hw_constraints_capture_buffer_sizes);
        emu->capture_mic_interrupt = snd_emu10k1_pcm_ac97mic_interrupt;
        emu->pcm_capture_mic_substream = substream;
        return 0;
}

static int snd_emu10k1_capture_mic_close(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);

        emu->capture_mic_interrupt = NULL;
        emu->pcm_capture_mic_substream = NULL;
        return 0;
}

static int snd_emu10k1_capture_efx_open(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_pcm *epcm;
        struct snd_pcm_runtime *runtime = substream->runtime;
        int nefx = emu->audigy ? 64 : 32;
        int idx, err;

        epcm = kzalloc_obj(*epcm);
        if (epcm == NULL)
                return -ENOMEM;
        epcm->emu = emu;
        epcm->type = CAPTURE_EFX;
        epcm->substream = substream;
        epcm->capture_ipr = IPR_EFXBUFFULL|IPR_EFXBUFHALFFULL;
        epcm->capture_inte = INTE_EFXBUFENABLE;
        epcm->capture_ba_reg = FXBA;
        epcm->capture_bs_reg = FXBS;
        epcm->capture_idx_reg = FXIDX;
        substream->runtime->private_data = epcm;
        substream->runtime->private_free = snd_emu10k1_pcm_free_substream;
        runtime->hw = snd_emu10k1_capture_efx;
        if (emu->card_capabilities->emu_model) {
                snd_emu1010_constrain_efx_rate(emu, runtime);
                /*
                 * There are 32 mono channels of 16bits each.
                 * 24bit Audio uses 2x channels over 16bit,
                 * 96kHz uses 2x channels over 48kHz,
                 * 192kHz uses 4x channels over 48kHz.
                 * So, for 48kHz 24bit, one has 16 channels,
                 * for 96kHz 24bit, one has 8 channels,
                 * for 192kHz 24bit, one has 4 channels.
                 * 1010rev2 and 1616(m) cards have double that,
                 * but we don't exceed 16 channels anyway.
                 */
#if 0
                /* For 96kHz */
                runtime->hw.channels_min = runtime->hw.channels_max = 4;
#endif
#if 0
                /* For 192kHz */
                runtime->hw.channels_min = runtime->hw.channels_max = 2;
#endif
                runtime->hw.formats = SNDRV_PCM_FMTBIT_S32_LE;
        } else {
                guard(spinlock_irq)(&emu->reg_lock);
                runtime->hw.channels_min = runtime->hw.channels_max = 0;
                for (idx = 0; idx < nefx; idx++) {
                        if (emu->efx_voices_mask[idx/32] & (1 << (idx%32))) {
                                runtime->hw.channels_min++;
                                runtime->hw.channels_max++;
                        }
                }
                epcm->capture_cr_val = emu->efx_voices_mask[0];
                epcm->capture_cr_val2 = emu->efx_voices_mask[1];
        }
        err = snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
                                         &hw_constraints_efx_capture_channels);
        if (err < 0) {
                kfree(epcm);
                return err;
        }
        snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
                                   &hw_constraints_capture_buffer_sizes);
        emu->capture_efx_interrupt = snd_emu10k1_pcm_efx_interrupt;
        emu->pcm_capture_efx_substream = substream;
        return 0;
}

static int snd_emu10k1_capture_efx_close(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);

        emu->capture_efx_interrupt = NULL;
        emu->pcm_capture_efx_substream = NULL;
        return 0;
}

static const struct snd_pcm_ops snd_emu10k1_playback_ops = {
        .open =                 snd_emu10k1_playback_open,
        .close =                snd_emu10k1_playback_close,
        .hw_params =            snd_emu10k1_playback_hw_params,
        .hw_free =              snd_emu10k1_playback_hw_free,
        .prepare =              snd_emu10k1_playback_prepare,
        .trigger =              snd_emu10k1_playback_trigger,
        .pointer =              snd_emu10k1_playback_pointer,
};

static const struct snd_pcm_ops snd_emu10k1_capture_ops = {
        .open =                 snd_emu10k1_capture_open,
        .close =                snd_emu10k1_capture_close,
        .prepare =              snd_emu10k1_capture_prepare,
        .trigger =              snd_emu10k1_capture_trigger,
        .pointer =              snd_emu10k1_capture_pointer,
};

/* EFX playback */
static const struct snd_pcm_ops snd_emu10k1_efx_playback_ops = {
        .open =                 snd_emu10k1_efx_playback_open,
        .close =                snd_emu10k1_efx_playback_close,
        .hw_params =            snd_emu10k1_playback_hw_params,
        .hw_free =              snd_emu10k1_playback_hw_free,
        .prepare =              snd_emu10k1_efx_playback_prepare,
        .trigger =              snd_emu10k1_efx_playback_trigger,
        .pointer =              snd_emu10k1_playback_pointer,
};

int snd_emu10k1_pcm(struct snd_emu10k1 *emu, int device)
{
        struct snd_pcm *pcm;
        struct snd_pcm_substream *substream;
        int err;

        err = snd_pcm_new(emu->card, "emu10k1", device, 32, 1, &pcm);
        if (err < 0)
                return err;

        pcm->private_data = emu;

        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_emu10k1_playback_ops);
        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_emu10k1_capture_ops);

        pcm->info_flags = 0;
        pcm->dev_subclass = SNDRV_PCM_SUBCLASS_GENERIC_MIX;
        strscpy(pcm->name, "ADC Capture/Standard PCM Playback");
        emu->pcm = pcm;

        /* playback substream can't use managed buffers due to alignment */
        for (substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; substream; substream = substream->next)
                snd_pcm_lib_preallocate_pages(substream, SNDRV_DMA_TYPE_DEV_SG,
                                              &emu->pci->dev,
                                              64*1024, 64*1024);

        for (substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; substream; substream = substream->next)
                snd_pcm_set_managed_buffer(substream, SNDRV_DMA_TYPE_DEV,
                                           &emu->pci->dev, 64*1024, 64*1024);

        return 0;
}

int snd_emu10k1_pcm_multi(struct snd_emu10k1 *emu, int device)
{
        struct snd_pcm *pcm;
        struct snd_pcm_substream *substream;
        int err;

        err = snd_pcm_new(emu->card, "emu10k1", device, 1, 0, &pcm);
        if (err < 0)
                return err;

        pcm->private_data = emu;

        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_emu10k1_efx_playback_ops);

        pcm->info_flags = 0;
        pcm->dev_subclass = SNDRV_PCM_SUBCLASS_GENERIC_MIX;
        strscpy(pcm->name, "Multichannel Playback");
        emu->pcm_multi = pcm;

        for (substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; substream; substream = substream->next)
                snd_pcm_lib_preallocate_pages(substream, SNDRV_DMA_TYPE_DEV_SG,
                                              &emu->pci->dev,
                                              64*1024, 64*1024);

        return 0;
}


static const struct snd_pcm_ops snd_emu10k1_capture_mic_ops = {
        .open =                 snd_emu10k1_capture_mic_open,
        .close =                snd_emu10k1_capture_mic_close,
        .prepare =              snd_emu10k1_capture_prepare,
        .trigger =              snd_emu10k1_capture_trigger,
        .pointer =              snd_emu10k1_capture_pointer,
};

int snd_emu10k1_pcm_mic(struct snd_emu10k1 *emu, int device)
{
        struct snd_pcm *pcm;
        int err;

        err = snd_pcm_new(emu->card, "emu10k1 mic", device, 0, 1, &pcm);
        if (err < 0)
                return err;

        pcm->private_data = emu;

        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_emu10k1_capture_mic_ops);

        pcm->info_flags = 0;
        strscpy(pcm->name, "Mic Capture");
        emu->pcm_mic = pcm;

        snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV, &emu->pci->dev,
                                       64*1024, 64*1024);

        return 0;
}

static int snd_emu10k1_pcm_efx_voices_mask_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
{
        struct snd_emu10k1 *emu = snd_kcontrol_chip(kcontrol);
        int nefx = emu->audigy ? 64 : 32;
        uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
        uinfo->count = nefx;
        uinfo->value.integer.min = 0;
        uinfo->value.integer.max = 1;
        return 0;
}

static int snd_emu10k1_pcm_efx_voices_mask_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
        struct snd_emu10k1 *emu = snd_kcontrol_chip(kcontrol);
        int nefx = emu->audigy ? 64 : 32;
        int idx;
        
        for (idx = 0; idx < nefx; idx++)
                ucontrol->value.integer.value[idx] = (emu->efx_voices_mask[idx / 32] & (1 << (idx % 32))) ? 1 : 0;
        return 0;
}

static int snd_emu10k1_pcm_efx_voices_mask_put(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
        struct snd_emu10k1 *emu = snd_kcontrol_chip(kcontrol);
        unsigned int nval[2], bits;
        int nefx = emu->audigy ? 64 : 32;
        int change, idx;
        
        nval[0] = nval[1] = 0;
        for (idx = 0, bits = 0; idx < nefx; idx++)
                if (ucontrol->value.integer.value[idx]) {
                        nval[idx / 32] |= 1 << (idx % 32);
                        bits++;
                }

        if (bits == 9 || bits == 11 || bits == 13 || bits == 15 || bits > 16)
                return -EINVAL;

        guard(spinlock_irq)(&emu->reg_lock);
        change = (nval[0] != emu->efx_voices_mask[0]) ||
                (nval[1] != emu->efx_voices_mask[1]);
        emu->efx_voices_mask[0] = nval[0];
        emu->efx_voices_mask[1] = nval[1];
        return change;
}

static const struct snd_kcontrol_new snd_emu10k1_pcm_efx_voices_mask = {
        .iface = SNDRV_CTL_ELEM_IFACE_PCM,
        .name = "Captured FX8010 Outputs",
        .info = snd_emu10k1_pcm_efx_voices_mask_info,
        .get = snd_emu10k1_pcm_efx_voices_mask_get,
        .put = snd_emu10k1_pcm_efx_voices_mask_put
};

static const struct snd_pcm_ops snd_emu10k1_capture_efx_ops = {
        .open =                 snd_emu10k1_capture_efx_open,
        .close =                snd_emu10k1_capture_efx_close,
        .prepare =              snd_emu10k1_capture_prepare,
        .trigger =              snd_emu10k1_capture_trigger,
        .pointer =              snd_emu10k1_capture_pointer,
};


/* EFX playback */

#define INITIAL_TRAM_SHIFT     14
#define INITIAL_TRAM_POS(size) ((((size) / 2) - INITIAL_TRAM_SHIFT) - 1)

static void snd_emu10k1_fx8010_playback_irq(struct snd_emu10k1 *emu, void *private_data)
{
        struct snd_pcm_substream *substream = private_data;
        snd_pcm_period_elapsed(substream);
}

static void snd_emu10k1_fx8010_playback_tram_poke1(unsigned short *dst_left,
                                                   unsigned short *dst_right,
                                                   unsigned short *src,
                                                   unsigned int count,
                                                   unsigned int tram_shift)
{
        /*
        dev_dbg(emu->card->dev,
                "tram_poke1: dst_left = 0x%p, dst_right = 0x%p, "
               "src = 0x%p, count = 0x%x\n",
               dst_left, dst_right, src, count);
        */
        if ((tram_shift & 1) == 0) {
                while (count--) {
                        *dst_left-- = *src++;
                        *dst_right-- = *src++;
                }
        } else {
                while (count--) {
                        *dst_right-- = *src++;
                        *dst_left-- = *src++;
                }
        }
}

static void fx8010_pb_trans_copy(struct snd_pcm_substream *substream,
                                 struct snd_pcm_indirect *rec, size_t bytes)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_fx8010_pcm *pcm = &emu->fx8010.pcm[substream->number];
        unsigned int tram_size = pcm->buffer_size;
        unsigned short *src = (unsigned short *)(substream->runtime->dma_area + rec->sw_data);
        unsigned int frames = bytes >> 2, count;
        unsigned int tram_pos = pcm->tram_pos;
        unsigned int tram_shift = pcm->tram_shift;

        while (frames > tram_pos) {
                count = tram_pos + 1;
                snd_emu10k1_fx8010_playback_tram_poke1((unsigned short *)emu->fx8010.etram_pages.area + tram_pos,
                                                       (unsigned short *)emu->fx8010.etram_pages.area + tram_pos + tram_size / 2,
                                                       src, count, tram_shift);
                src += count * 2;
                frames -= count;
                tram_pos = (tram_size / 2) - 1;
                tram_shift++;
        }
        snd_emu10k1_fx8010_playback_tram_poke1((unsigned short *)emu->fx8010.etram_pages.area + tram_pos,
                                               (unsigned short *)emu->fx8010.etram_pages.area + tram_pos + tram_size / 2,
                                               src, frames, tram_shift);
        tram_pos -= frames;
        pcm->tram_pos = tram_pos;
        pcm->tram_shift = tram_shift;
}

static int snd_emu10k1_fx8010_playback_transfer(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_fx8010_pcm *pcm = &emu->fx8010.pcm[substream->number];

        return snd_pcm_indirect_playback_transfer(substream, &pcm->pcm_rec,
                                                  fx8010_pb_trans_copy);
}

static int snd_emu10k1_fx8010_playback_hw_free(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_fx8010_pcm *pcm = &emu->fx8010.pcm[substream->number];
        unsigned int i;

        for (i = 0; i < pcm->channels; i++)
                snd_emu10k1_ptr_write(emu, TANKMEMADDRREGBASE + 0x80 + pcm->etram[i], 0, 0);
        return 0;
}

static int snd_emu10k1_fx8010_playback_prepare(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_fx8010_pcm *pcm = &emu->fx8010.pcm[substream->number];
        unsigned int i;
        
        /*
        dev_dbg(emu->card->dev, "prepare: etram_pages = 0x%p, dma_area = 0x%x, "
               "buffer_size = 0x%x (0x%x)\n",
               emu->fx8010.etram_pages, runtime->dma_area,
               runtime->buffer_size, runtime->buffer_size << 2);
        */
        memset(&pcm->pcm_rec, 0, sizeof(pcm->pcm_rec));
        pcm->pcm_rec.hw_buffer_size = pcm->buffer_size * 2; /* byte size */
        pcm->pcm_rec.sw_buffer_size = snd_pcm_lib_buffer_bytes(substream);
        pcm->tram_pos = INITIAL_TRAM_POS(pcm->buffer_size);
        pcm->tram_shift = 0;
        snd_emu10k1_ptr_write_multiple(emu, 0,
                emu->gpr_base + pcm->gpr_running, 0,    /* reset */
                emu->gpr_base + pcm->gpr_trigger, 0,    /* reset */
                emu->gpr_base + pcm->gpr_size, runtime->buffer_size,
                emu->gpr_base + pcm->gpr_ptr, 0,        /* reset ptr number */
                emu->gpr_base + pcm->gpr_count, runtime->period_size,
                emu->gpr_base + pcm->gpr_tmpcount, runtime->period_size,
                REGLIST_END);
        for (i = 0; i < pcm->channels; i++)
                snd_emu10k1_ptr_write(emu, TANKMEMADDRREGBASE + 0x80 + pcm->etram[i], 0, (TANKMEMADDRREG_READ|TANKMEMADDRREG_ALIGN) + i * (runtime->buffer_size / pcm->channels));
        return 0;
}

static int snd_emu10k1_fx8010_playback_trigger(struct snd_pcm_substream *substream, int cmd)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_fx8010_pcm *pcm = &emu->fx8010.pcm[substream->number];
        int result;

        guard(spinlock)(&emu->reg_lock);
        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
                /* follow thru */
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
        case SNDRV_PCM_TRIGGER_RESUME:
#ifdef EMU10K1_SET_AC3_IEC958
        {
                int i;
                for (i = 0; i < 3; i++) {
                        unsigned int bits;
                        bits = SPCS_CLKACCY_1000PPM | SPCS_SAMPLERATE_48 |
                               SPCS_CHANNELNUM_LEFT | SPCS_SOURCENUM_UNSPEC | SPCS_GENERATIONSTATUS |
                               0x00001200 | SPCS_EMPHASIS_NONE | SPCS_COPYRIGHT | SPCS_NOTAUDIODATA;
                        snd_emu10k1_ptr_write(emu, SPCS0 + i, 0, bits);
                }
        }
#endif
                result = snd_emu10k1_fx8010_register_irq_handler(emu, snd_emu10k1_fx8010_playback_irq, pcm->gpr_running, substream, &pcm->irq);
                if (result < 0)
                        return result;
                snd_emu10k1_fx8010_playback_transfer(substream);        /* roll the ball */
                snd_emu10k1_ptr_write(emu, emu->gpr_base + pcm->gpr_trigger, 0, 1);
                break;
        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
        case SNDRV_PCM_TRIGGER_SUSPEND:
                snd_emu10k1_fx8010_unregister_irq_handler(emu, &pcm->irq);
                snd_emu10k1_ptr_write(emu, emu->gpr_base + pcm->gpr_trigger, 0, 0);
                pcm->tram_pos = INITIAL_TRAM_POS(pcm->buffer_size);
                pcm->tram_shift = 0;
                break;
        default:
                return -EINVAL;
        }
        return 0;
}

static snd_pcm_uframes_t snd_emu10k1_fx8010_playback_pointer(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_fx8010_pcm *pcm = &emu->fx8010.pcm[substream->number];
        size_t ptr; /* byte pointer */

        if (!snd_emu10k1_ptr_read(emu, emu->gpr_base + pcm->gpr_trigger, 0))
                return 0;
        ptr = snd_emu10k1_ptr_read(emu, emu->gpr_base + pcm->gpr_ptr, 0) << 2;
        return snd_pcm_indirect_playback_pointer(substream, &pcm->pcm_rec, ptr);
}

static const struct snd_pcm_hardware snd_emu10k1_fx8010_playback =
{
        .info =                 (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
                                 SNDRV_PCM_INFO_RESUME |
                                 /* SNDRV_PCM_INFO_MMAP_VALID | */ SNDRV_PCM_INFO_PAUSE |
                                 SNDRV_PCM_INFO_SYNC_APPLPTR),
        .formats =              SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE,
        .rates =                SNDRV_PCM_RATE_48000,
        .rate_min =             48000,
        .rate_max =             48000,
        .channels_min =         1,
        .channels_max =         1,
        .buffer_bytes_max =     (128*1024),
        .period_bytes_min =     1024,
        .period_bytes_max =     (128*1024),
        .periods_min =          2,
        .periods_max =          1024,
        .fifo_size =            0,
};

static int snd_emu10k1_fx8010_playback_open(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_emu10k1_fx8010_pcm *pcm = &emu->fx8010.pcm[substream->number];

        runtime->hw = snd_emu10k1_fx8010_playback;
        runtime->hw.channels_min = runtime->hw.channels_max = pcm->channels;
        runtime->hw.period_bytes_max = (pcm->buffer_size * 2) / 2;
        guard(spinlock_irq)(&emu->reg_lock);
        if (pcm->valid == 0)
                return -ENODEV;
        pcm->opened = 1;
        return 0;
}

static int snd_emu10k1_fx8010_playback_close(struct snd_pcm_substream *substream)
{
        struct snd_emu10k1 *emu = snd_pcm_substream_chip(substream);
        struct snd_emu10k1_fx8010_pcm *pcm = &emu->fx8010.pcm[substream->number];

        guard(spinlock_irq)(&emu->reg_lock);
        pcm->opened = 0;
        return 0;
}

static const struct snd_pcm_ops snd_emu10k1_fx8010_playback_ops = {
        .open =                 snd_emu10k1_fx8010_playback_open,
        .close =                snd_emu10k1_fx8010_playback_close,
        .hw_free =              snd_emu10k1_fx8010_playback_hw_free,
        .prepare =              snd_emu10k1_fx8010_playback_prepare,
        .trigger =              snd_emu10k1_fx8010_playback_trigger,
        .pointer =              snd_emu10k1_fx8010_playback_pointer,
        .ack =                  snd_emu10k1_fx8010_playback_transfer,
};

int snd_emu10k1_pcm_efx(struct snd_emu10k1 *emu, int device)
{
        struct snd_pcm *pcm;
        struct snd_kcontrol *kctl;
        int err;

        err = snd_pcm_new(emu->card, "emu10k1 efx", device, emu->audigy ? 0 : 8, 1, &pcm);
        if (err < 0)
                return err;

        pcm->private_data = emu;

        if (!emu->audigy)
                snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_emu10k1_fx8010_playback_ops);
        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_emu10k1_capture_efx_ops);

        pcm->info_flags = 0;
        if (emu->audigy)
                strscpy(pcm->name, "Multichannel Capture");
        else
                strscpy(pcm->name, "Multichannel Capture/PT Playback");
        emu->pcm_efx = pcm;

        if (!emu->card_capabilities->emu_model) {
                // On Sound Blasters, the DSP code copies the EXTINs to FXBUS2.
                // The mask determines which of these and the EXTOUTs the multi-
                // channel capture actually records (the channel order is fixed).
                if (emu->audigy) {
                        emu->efx_voices_mask[0] = 0;
                        emu->efx_voices_mask[1] = 0xffff;
                } else {
                        emu->efx_voices_mask[0] = 0xffff0000;
                        emu->efx_voices_mask[1] = 0;
                }
                kctl = snd_ctl_new1(&snd_emu10k1_pcm_efx_voices_mask, emu);
                if (!kctl)
                        return -ENOMEM;
                kctl->id.device = device;
                err = snd_ctl_add(emu->card, kctl);
                if (err < 0)
                        return err;
        } else {
                // On E-MU cards, the DSP code copies the P16VINs/EMU32INs to
                // FXBUS2. These are already selected & routed by the FPGA,
                // so there is no need to apply additional masking.
        }

        snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV, &emu->pci->dev,
                                       64*1024, 64*1024);

        return 0;
}