// SPDX-License-Identifier: GPL-2.0-only
/*
 * fireworks_pcm.c - a part of driver for Fireworks based devices
 *
 * Copyright (c) 2009-2010 Clemens Ladisch
 * Copyright (c) 2013-2014 Takashi Sakamoto
 */
#include "./fireworks.h"

/*
 * NOTE:
 * Fireworks changes its AMDTP channels for PCM data according to its sampling
 * rate. There are three modes. Here _XX is either _rx or _tx.
 *  0:  32.0- 48.0 kHz then snd_efw_hwinfo.amdtp_XX_pcm_channels applied
 *  1:  88.2- 96.0 kHz then snd_efw_hwinfo.amdtp_XX_pcm_channels_2x applied
 *  2: 176.4-192.0 kHz then snd_efw_hwinfo.amdtp_XX_pcm_channels_4x applied
 *
 * The number of PCM channels for analog input and output are always fixed but
 * the number of PCM channels for digital input and output are differed.
 *
 * Additionally, according to "AudioFire Owner's Manual Version 2.2", in some
 * model, the number of PCM channels for digital input has more restriction
 * depending on which digital interface is selected.
 *  - S/PDIF coaxial and optical        : use input 1-2
 *  - ADAT optical at 32.0-48.0 kHz     : use input 1-8
 *  - ADAT optical at 88.2-96.0 kHz     : use input 1-4 (S/MUX format)
 *
 * The data in AMDTP channels for blank PCM channels are zero.
 */
static const unsigned int freq_table[] = {
        /* multiplier mode 0 */
        [0] = 32000,
        [1] = 44100,
        [2] = 48000,
        /* multiplier mode 1 */
        [3] = 88200,
        [4] = 96000,
        /* multiplier mode 2 */
        [5] = 176400,
        [6] = 192000,
};

static inline unsigned int
get_multiplier_mode_with_index(unsigned int index)
{
        return ((int)index - 1) / 2;
}

int snd_efw_get_multiplier_mode(unsigned int sampling_rate, unsigned int *mode)
{
        unsigned int i;

        for (i = 0; i < ARRAY_SIZE(freq_table); i++) {
                if (freq_table[i] == sampling_rate) {
                        *mode = get_multiplier_mode_with_index(i);
                        return 0;
                }
        }

        return -EINVAL;
}

static int
hw_rule_rate(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
{
        unsigned int *pcm_channels = rule->private;
        struct snd_interval *r =
                hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
        const struct snd_interval *c =
                hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_CHANNELS);
        struct snd_interval t = {
                .min = UINT_MAX, .max = 0, .integer = 1
        };
        unsigned int i, mode;

        for (i = 0; i < ARRAY_SIZE(freq_table); i++) {
                mode = get_multiplier_mode_with_index(i);
                if (!snd_interval_test(c, pcm_channels[mode]))
                        continue;

                t.min = min(t.min, freq_table[i]);
                t.max = max(t.max, freq_table[i]);
        }

        return snd_interval_refine(r, &t);
}

static int
hw_rule_channels(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
{
        unsigned int *pcm_channels = rule->private;
        struct snd_interval *c =
                hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
        const struct snd_interval *r =
                hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE);
        struct snd_interval t = {
                .min = UINT_MAX, .max = 0, .integer = 1
        };
        unsigned int i, mode;

        for (i = 0; i < ARRAY_SIZE(freq_table); i++) {
                mode = get_multiplier_mode_with_index(i);
                if (!snd_interval_test(r, freq_table[i]))
                        continue;

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

        return snd_interval_refine(c, &t);
}

static void
limit_channels(struct snd_pcm_hardware *hw, unsigned int *pcm_channels)
{
        unsigned int i, mode;

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

        for (i = 0; i < ARRAY_SIZE(freq_table); i++) {
                mode = get_multiplier_mode_with_index(i);
                if (pcm_channels[mode] == 0)
                        continue;

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

static int
pcm_init_hw_params(struct snd_efw *efw,
                   struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct amdtp_stream *s;
        unsigned int *pcm_channels;
        int err;

        if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
                runtime->hw.formats = AM824_IN_PCM_FORMAT_BITS;
                s = &efw->tx_stream;
                pcm_channels = efw->pcm_capture_channels;
        } else {
                runtime->hw.formats = AM824_OUT_PCM_FORMAT_BITS;
                s = &efw->rx_stream;
                pcm_channels = efw->pcm_playback_channels;
        }

        /* limit rates */
        runtime->hw.rates = efw->supported_sampling_rate;
        snd_pcm_limit_hw_rates(runtime);

        limit_channels(&runtime->hw, pcm_channels);

        err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
                                  hw_rule_channels, pcm_channels,
                                  SNDRV_PCM_HW_PARAM_RATE, -1);
        if (err < 0)
                goto end;

        err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
                                  hw_rule_rate, pcm_channels,
                                  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
        if (err < 0)
                goto end;

        err = amdtp_am824_add_pcm_hw_constraints(s, runtime);
end:
        return err;
}

static int pcm_open(struct snd_pcm_substream *substream)
{
        struct snd_efw *efw = substream->private_data;
        struct amdtp_domain *d = &efw->domain;
        enum snd_efw_clock_source clock_source;
        int err;

        err = snd_efw_stream_lock_try(efw);
        if (err < 0)
                return err;

        err = pcm_init_hw_params(efw, substream);
        if (err < 0)
                goto err_locked;

        err = snd_efw_command_get_clock_source(efw, &clock_source);
        if (err < 0)
                goto err_locked;

        scoped_guard(mutex, &efw->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 ((clock_source != SND_EFW_CLOCK_SOURCE_INTERNAL) ||
                    (efw->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 sampling_rate;

                        err = snd_efw_command_get_sampling_rate(efw, &sampling_rate);
                        if (err < 0)
                                goto err_locked;
                        substream->runtime->hw.rate_min = sampling_rate;
                        substream->runtime->hw.rate_max = sampling_rate;

                        if (frames_per_period > 0) {
                                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_efw_stream_lock_release(efw);
        return err;
}

static int pcm_close(struct snd_pcm_substream *substream)
{
        struct snd_efw *efw = substream->private_data;
        snd_efw_stream_lock_release(efw);
        return 0;
}

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

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

                guard(mutex)(&efw->mutex);
                err = snd_efw_stream_reserve_duplex(efw, rate,
                                        frames_per_period, frames_per_buffer);
                if (err >= 0)
                        ++efw->substreams_counter;
        }

        return err;
}

static int pcm_hw_free(struct snd_pcm_substream *substream)
{
        struct snd_efw *efw = substream->private_data;

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

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

        snd_efw_stream_stop_duplex(efw);

        return 0;
}

static int pcm_capture_prepare(struct snd_pcm_substream *substream)
{
        struct snd_efw *efw = substream->private_data;
        int err;

        err = snd_efw_stream_start_duplex(efw);
        if (err >= 0)
                amdtp_stream_pcm_prepare(&efw->tx_stream);

        return err;
}
static int pcm_playback_prepare(struct snd_pcm_substream *substream)
{
        struct snd_efw *efw = substream->private_data;
        int err;

        err = snd_efw_stream_start_duplex(efw);
        if (err >= 0)
                amdtp_stream_pcm_prepare(&efw->rx_stream);

        return err;
}

static int pcm_capture_trigger(struct snd_pcm_substream *substream, int cmd)
{
        struct snd_efw *efw = substream->private_data;

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

        return 0;
}
static int pcm_playback_trigger(struct snd_pcm_substream *substream, int cmd)
{
        struct snd_efw *efw = substream->private_data;

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

        return 0;
}

static snd_pcm_uframes_t pcm_capture_pointer(struct snd_pcm_substream *sbstrm)
{
        struct snd_efw *efw = sbstrm->private_data;

        return amdtp_domain_stream_pcm_pointer(&efw->domain, &efw->tx_stream);
}
static snd_pcm_uframes_t pcm_playback_pointer(struct snd_pcm_substream *sbstrm)
{
        struct snd_efw *efw = sbstrm->private_data;

        return amdtp_domain_stream_pcm_pointer(&efw->domain, &efw->rx_stream);
}

static int pcm_capture_ack(struct snd_pcm_substream *substream)
{
        struct snd_efw *efw = substream->private_data;

        return amdtp_domain_stream_pcm_ack(&efw->domain, &efw->tx_stream);
}

static int pcm_playback_ack(struct snd_pcm_substream *substream)
{
        struct snd_efw *efw = substream->private_data;

        return amdtp_domain_stream_pcm_ack(&efw->domain, &efw->rx_stream);
}

int snd_efw_create_pcm_devices(struct snd_efw *efw)
{
        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        = pcm_capture_prepare,
                .trigger        = pcm_capture_trigger,
                .pointer        = pcm_capture_pointer,
                .ack            = pcm_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        = pcm_playback_prepare,
                .trigger        = pcm_playback_trigger,
                .pointer        = pcm_playback_pointer,
                .ack            = pcm_playback_ack,
        };
        struct snd_pcm *pcm;
        int err;

        err = snd_pcm_new(efw->card, efw->card->driver, 0, 1, 1, &pcm);
        if (err < 0)
                goto end;

        pcm->private_data = efw;
        pcm->nonatomic = true;
        snprintf(pcm->name, sizeof(pcm->name), "%s PCM", efw->card->shortname);
        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &playback_ops);
        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &capture_ops);
        snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC, NULL, 0, 0);
end:
        return err;
}