// SPDX-License-Identifier: GPL-2.0-only
/*
 * dice_pcm.c - a part of driver for DICE based devices
 *
 * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
 * Copyright (c) 2014 Takashi Sakamoto <o-takashi@sakamocchi.jp>
 */

#include "dice.h"

static int dice_rate_constraint(struct snd_pcm_hw_params *params,
                                struct snd_pcm_hw_rule *rule)
{
        struct snd_pcm_substream *substream = rule->private;
        struct snd_dice *dice = substream->private_data;
        unsigned int index = substream->pcm->device;

        const struct snd_interval *c =
                hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_CHANNELS);
        struct snd_interval *r =
                hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
        struct snd_interval rates = {
                .min = UINT_MAX, .max = 0, .integer = 1
        };
        unsigned int *pcm_channels;
        enum snd_dice_rate_mode mode;
        unsigned int i, rate;

        if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
                pcm_channels = dice->tx_pcm_chs[index];
        else
                pcm_channels = dice->rx_pcm_chs[index];

        for (i = 0; i < ARRAY_SIZE(snd_dice_rates); ++i) {
                rate = snd_dice_rates[i];
                if (snd_dice_stream_get_rate_mode(dice, rate, &mode) < 0)
                        continue;

                if (!snd_interval_test(c, pcm_channels[mode]))
                        continue;

                rates.min = min(rates.min, rate);
                rates.max = max(rates.max, rate);
        }

        return snd_interval_refine(r, &rates);
}

static int dice_channels_constraint(struct snd_pcm_hw_params *params,
                                    struct snd_pcm_hw_rule *rule)
{
        struct snd_pcm_substream *substream = rule->private;
        struct snd_dice *dice = substream->private_data;
        unsigned int index = substream->pcm->device;

        const struct snd_interval *r =
                hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE);
        struct snd_interval *c =
                hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
        struct snd_interval channels = {
                .min = UINT_MAX, .max = 0, .integer = 1
        };
        unsigned int *pcm_channels;
        enum snd_dice_rate_mode mode;
        unsigned int i, rate;

        if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
                pcm_channels = dice->tx_pcm_chs[index];
        else
                pcm_channels = dice->rx_pcm_chs[index];

        for (i = 0; i < ARRAY_SIZE(snd_dice_rates); ++i) {
                rate = snd_dice_rates[i];
                if (snd_dice_stream_get_rate_mode(dice, rate, &mode) < 0)
                        continue;

                if (!snd_interval_test(r, rate))
                        continue;

                channels.min = min(channels.min, pcm_channels[mode]);
                channels.max = max(channels.max, pcm_channels[mode]);
        }

        return snd_interval_refine(c, &channels);
}

static int limit_channels_and_rates(struct snd_dice *dice,
                                    struct snd_pcm_runtime *runtime,
                                    enum amdtp_stream_direction dir,
                                    unsigned int index)
{
        struct snd_pcm_hardware *hw = &runtime->hw;
        unsigned int *pcm_channels;
        unsigned int i;

        if (dir == AMDTP_IN_STREAM)
                pcm_channels = dice->tx_pcm_chs[index];
        else
                pcm_channels = dice->rx_pcm_chs[index];

        hw->channels_min = UINT_MAX;
        hw->channels_max = 0;

        for (i = 0; i < ARRAY_SIZE(snd_dice_rates); ++i) {
                enum snd_dice_rate_mode mode;
                unsigned int rate, channels;

                rate = snd_dice_rates[i];
                if (snd_dice_stream_get_rate_mode(dice, rate, &mode) < 0)
                        continue;
                hw->rates |= snd_pcm_rate_to_rate_bit(rate);

                channels = pcm_channels[mode];
                if (channels == 0)
                        continue;
                hw->channels_min = min(hw->channels_min, channels);
                hw->channels_max = max(hw->channels_max, channels);
        }

        snd_pcm_limit_hw_rates(runtime);

        return 0;
}

static int init_hw_info(struct snd_dice *dice,
                        struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_pcm_hardware *hw = &runtime->hw;
        unsigned int index = substream->pcm->device;
        enum amdtp_stream_direction dir;
        struct amdtp_stream *stream;
        int err;

        if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
                hw->formats = AM824_IN_PCM_FORMAT_BITS;
                dir = AMDTP_IN_STREAM;
                stream = &dice->tx_stream[index];
        } else {
                hw->formats = AM824_OUT_PCM_FORMAT_BITS;
                dir = AMDTP_OUT_STREAM;
                stream = &dice->rx_stream[index];
        }

        err = limit_channels_and_rates(dice, substream->runtime, dir,
                                       index);
        if (err < 0)
                return err;

        err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
                                  dice_rate_constraint, substream,
                                  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
        if (err < 0)
                return err;
        err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
                                  dice_channels_constraint, substream,
                                  SNDRV_PCM_HW_PARAM_RATE, -1);
        if (err < 0)
                return err;

        return amdtp_am824_add_pcm_hw_constraints(stream, runtime);
}

static int pcm_open(struct snd_pcm_substream *substream)
{
        struct snd_dice *dice = substream->private_data;
        struct amdtp_domain *d = &dice->domain;
        unsigned int source;
        bool internal;
        int err;

        err = snd_dice_stream_lock_try(dice);
        if (err < 0)
                return err;

        err = init_hw_info(dice, substream);
        if (err < 0)
                goto err_locked;

        err = snd_dice_transaction_get_clock_source(dice, &source);
        if (err < 0)
                goto err_locked;
        switch (source) {
        case CLOCK_SOURCE_AES1:
        case CLOCK_SOURCE_AES2:
        case CLOCK_SOURCE_AES3:
        case CLOCK_SOURCE_AES4:
        case CLOCK_SOURCE_AES_ANY:
        case CLOCK_SOURCE_ADAT:
        case CLOCK_SOURCE_TDIF:
        case CLOCK_SOURCE_WC:
                internal = false;
                break;
        default:
                internal = true;
                break;
        }

        scoped_guard(mutex, &dice->mutex) {
                // When source of clock is not internal or any stream is reserved for
                // transmission of PCM frames, the available sampling rate is limited
                // at current one.
                if (!internal ||
                    (dice->substreams_counter > 0 && d->events_per_period > 0)) {
                        unsigned int frames_per_period = d->events_per_period;
                        unsigned int frames_per_buffer = d->events_per_buffer;
                        unsigned int rate;

                        err = snd_dice_transaction_get_rate(dice, &rate);
                        if (err < 0)
                                goto err_locked;

                        substream->runtime->hw.rate_min = rate;
                        substream->runtime->hw.rate_max = rate;

                        if (frames_per_period > 0) {
                                // For double_pcm_frame quirk.
                                if (rate > 96000 && !dice->disable_double_pcm_frames) {
                                        frames_per_period *= 2;
                                        frames_per_buffer *= 2;
                                }

                                err = snd_pcm_hw_constraint_minmax(substream->runtime,
                                                                   SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
                                                                   frames_per_period, frames_per_period);
                                if (err < 0)
                                        goto err_locked;

                                err = snd_pcm_hw_constraint_minmax(substream->runtime,
                                                                   SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
                                                                   frames_per_buffer, frames_per_buffer);
                                if (err < 0)
                                        goto err_locked;
                        }
                }
        }

        snd_pcm_set_sync(substream);

        return 0;
err_locked:
        snd_dice_stream_lock_release(dice);
        return err;
}

static int pcm_close(struct snd_pcm_substream *substream)
{
        struct snd_dice *dice = substream->private_data;

        snd_dice_stream_lock_release(dice);

        return 0;
}

static int pcm_hw_params(struct snd_pcm_substream *substream,
                         struct snd_pcm_hw_params *hw_params)
{
        struct snd_dice *dice = substream->private_data;
        int err = 0;

        if (substream->runtime->state == SNDRV_PCM_STATE_OPEN) {
                unsigned int rate = params_rate(hw_params);
                unsigned int events_per_period = params_period_size(hw_params);
                unsigned int events_per_buffer = params_buffer_size(hw_params);

                guard(mutex)(&dice->mutex);
                // For double_pcm_frame quirk.
                if (rate > 96000 && !dice->disable_double_pcm_frames) {
                        events_per_period /= 2;
                        events_per_buffer /= 2;
                }
                err = snd_dice_stream_reserve_duplex(dice, rate,
                                        events_per_period, events_per_buffer);
                if (err >= 0)
                        ++dice->substreams_counter;
        }

        return err;
}

static int pcm_hw_free(struct snd_pcm_substream *substream)
{
        struct snd_dice *dice = substream->private_data;

        guard(mutex)(&dice->mutex);

        if (substream->runtime->state != SNDRV_PCM_STATE_OPEN)
                --dice->substreams_counter;

        snd_dice_stream_stop_duplex(dice);

        return 0;
}

static int capture_prepare(struct snd_pcm_substream *substream)
{
        struct snd_dice *dice = substream->private_data;
        struct amdtp_stream *stream = &dice->tx_stream[substream->pcm->device];
        int err;

        scoped_guard(mutex, &dice->mutex) {
                err = snd_dice_stream_start_duplex(dice);
        }
        if (err >= 0)
                amdtp_stream_pcm_prepare(stream);

        return 0;
}
static int playback_prepare(struct snd_pcm_substream *substream)
{
        struct snd_dice *dice = substream->private_data;
        struct amdtp_stream *stream = &dice->rx_stream[substream->pcm->device];
        int err;

        scoped_guard(mutex, &dice->mutex) {
                err = snd_dice_stream_start_duplex(dice);
        }
        if (err >= 0)
                amdtp_stream_pcm_prepare(stream);

        return err;
}

static int capture_trigger(struct snd_pcm_substream *substream, int cmd)
{
        struct snd_dice *dice = substream->private_data;
        struct amdtp_stream *stream = &dice->tx_stream[substream->pcm->device];

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
                amdtp_stream_pcm_trigger(stream, substream);
                break;
        case SNDRV_PCM_TRIGGER_STOP:
                amdtp_stream_pcm_trigger(stream, NULL);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}
static int playback_trigger(struct snd_pcm_substream *substream, int cmd)
{
        struct snd_dice *dice = substream->private_data;
        struct amdtp_stream *stream = &dice->rx_stream[substream->pcm->device];

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
                amdtp_stream_pcm_trigger(stream, substream);
                break;
        case SNDRV_PCM_TRIGGER_STOP:
                amdtp_stream_pcm_trigger(stream, NULL);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static snd_pcm_uframes_t capture_pointer(struct snd_pcm_substream *substream)
{
        struct snd_dice *dice = substream->private_data;
        struct amdtp_stream *stream = &dice->tx_stream[substream->pcm->device];

        return amdtp_domain_stream_pcm_pointer(&dice->domain, stream);
}
static snd_pcm_uframes_t playback_pointer(struct snd_pcm_substream *substream)
{
        struct snd_dice *dice = substream->private_data;
        struct amdtp_stream *stream = &dice->rx_stream[substream->pcm->device];

        return amdtp_domain_stream_pcm_pointer(&dice->domain, stream);
}

static int capture_ack(struct snd_pcm_substream *substream)
{
        struct snd_dice *dice = substream->private_data;
        struct amdtp_stream *stream = &dice->tx_stream[substream->pcm->device];

        return amdtp_domain_stream_pcm_ack(&dice->domain, stream);
}

static int playback_ack(struct snd_pcm_substream *substream)
{
        struct snd_dice *dice = substream->private_data;
        struct amdtp_stream *stream = &dice->rx_stream[substream->pcm->device];

        return amdtp_domain_stream_pcm_ack(&dice->domain, stream);
}

int snd_dice_create_pcm(struct snd_dice *dice)
{
        static const struct snd_pcm_ops capture_ops = {
                .open      = pcm_open,
                .close     = pcm_close,
                .hw_params = pcm_hw_params,
                .hw_free   = pcm_hw_free,
                .prepare   = capture_prepare,
                .trigger   = capture_trigger,
                .pointer   = capture_pointer,
                .ack       = capture_ack,
        };
        static const struct snd_pcm_ops playback_ops = {
                .open      = pcm_open,
                .close     = pcm_close,
                .hw_params = pcm_hw_params,
                .hw_free   = pcm_hw_free,
                .prepare   = playback_prepare,
                .trigger   = playback_trigger,
                .pointer   = playback_pointer,
                .ack       = playback_ack,
        };
        struct snd_pcm *pcm;
        unsigned int capture, playback;
        int i, j;
        int err;

        for (i = 0; i < MAX_STREAMS; i++) {
                capture = playback = 0;
                for (j = 0; j < SND_DICE_RATE_MODE_COUNT; ++j) {
                        if (dice->tx_pcm_chs[i][j] > 0)
                                capture = 1;
                        if (dice->rx_pcm_chs[i][j] > 0)
                                playback = 1;
                }

                err = snd_pcm_new(dice->card, "DICE", i, playback, capture,
                                  &pcm);
                if (err < 0)
                        return err;
                pcm->private_data = dice;
                pcm->nonatomic = true;
                strscpy(pcm->name, dice->card->shortname);

                if (capture > 0)
                        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
                                        &capture_ops);

                if (playback > 0)
                        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
                                        &playback_ops);

                snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC,
                                               NULL, 0, 0);
        }

        return 0;
}