root/sound/firewire/digi00x/digi00x-pcm.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * digi00x-pcm.c - a part of driver for Digidesign Digi 002/003 family
 *
 * Copyright (c) 2014-2015 Takashi Sakamoto
 */

#include "digi00x.h"

static int hw_rule_rate(struct snd_pcm_hw_params *params,
                        struct snd_pcm_hw_rule *rule)
{
        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;

        for (i = 0; i < SND_DG00X_RATE_COUNT; i++) {
                if (!snd_interval_test(c,
                                       snd_dg00x_stream_pcm_channels[i]))
                        continue;

                t.min = min(t.min, snd_dg00x_stream_rates[i]);
                t.max = max(t.max, snd_dg00x_stream_rates[i]);
        }

        return snd_interval_refine(r, &t);
}

static int hw_rule_channels(struct snd_pcm_hw_params *params,
                            struct snd_pcm_hw_rule *rule)
{
        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;

        for (i = 0; i < SND_DG00X_RATE_COUNT; i++) {
                if (!snd_interval_test(r, snd_dg00x_stream_rates[i]))
                        continue;

                t.min = min(t.min, snd_dg00x_stream_pcm_channels[i]);
                t.max = max(t.max, snd_dg00x_stream_pcm_channels[i]);
        }

        return snd_interval_refine(c, &t);
}

static int pcm_init_hw_params(struct snd_dg00x *dg00x,
                              struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct snd_pcm_hardware *hw = &runtime->hw;
        struct amdtp_stream *s;
        int err;


        if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
                substream->runtime->hw.formats = SNDRV_PCM_FMTBIT_S32;
                s = &dg00x->tx_stream;
        } else {
                substream->runtime->hw.formats = SNDRV_PCM_FMTBIT_S32;
                s = &dg00x->rx_stream;
        }

        hw->channels_min = 10;
        hw->channels_max = 18;

        hw->rates = SNDRV_PCM_RATE_44100 |
                    SNDRV_PCM_RATE_48000 |
                    SNDRV_PCM_RATE_88200 |
                    SNDRV_PCM_RATE_96000;
        snd_pcm_limit_hw_rates(runtime);

        err = snd_pcm_hw_rule_add(substream->runtime, 0,
                                  SNDRV_PCM_HW_PARAM_CHANNELS,
                                  hw_rule_channels, NULL,
                                  SNDRV_PCM_HW_PARAM_RATE, -1);
        if (err < 0)
                return err;

        err = snd_pcm_hw_rule_add(substream->runtime, 0,
                                  SNDRV_PCM_HW_PARAM_RATE,
                                  hw_rule_rate, NULL,
                                  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
        if (err < 0)
                return err;

        return amdtp_dot_add_pcm_hw_constraints(s, substream->runtime);
}

static int pcm_open(struct snd_pcm_substream *substream)
{
        struct snd_dg00x *dg00x = substream->private_data;
        struct amdtp_domain *d = &dg00x->domain;
        enum snd_dg00x_clock clock;
        bool detect;
        int err;

        err = snd_dg00x_stream_lock_try(dg00x);
        if (err < 0)
                return err;

        err = pcm_init_hw_params(dg00x, substream);
        if (err < 0)
                goto err_locked;

        /* Check current clock source. */
        err = snd_dg00x_stream_get_clock(dg00x, &clock);
        if (err < 0)
                goto err_locked;
        if (clock != SND_DG00X_CLOCK_INTERNAL) {
                err = snd_dg00x_stream_check_external_clock(dg00x, &detect);
                if (err < 0)
                        goto err_locked;
                if (!detect) {
                        err = -EBUSY;
                        goto err_locked;
                }
        }

        scoped_guard(mutex, &dg00x->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 != SND_DG00X_CLOCK_INTERNAL) ||
                    (dg00x->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_dg00x_stream_get_external_rate(dg00x, &rate);
                        if (err < 0)
                                goto err_locked;
                        substream->runtime->hw.rate_min = rate;
                        substream->runtime->hw.rate_max = 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_dg00x_stream_lock_release(dg00x);
        return err;
}

static int pcm_close(struct snd_pcm_substream *substream)
{
        struct snd_dg00x *dg00x = substream->private_data;

        snd_dg00x_stream_lock_release(dg00x);

        return 0;
}

static int pcm_hw_params(struct snd_pcm_substream *substream,
                         struct snd_pcm_hw_params *hw_params)
{
        struct snd_dg00x *dg00x = 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)(&dg00x->mutex);
                err = snd_dg00x_stream_reserve_duplex(dg00x, rate,
                                        frames_per_period, frames_per_buffer);
                if (err >= 0)
                        ++dg00x->substreams_counter;
        }

        return err;
}

static int pcm_hw_free(struct snd_pcm_substream *substream)
{
        struct snd_dg00x *dg00x = substream->private_data;

        guard(mutex)(&dg00x->mutex);

        if (substream->runtime->state != SNDRV_PCM_STATE_OPEN)
                --dg00x->substreams_counter;

        snd_dg00x_stream_stop_duplex(dg00x);

        return 0;
}

static int pcm_capture_prepare(struct snd_pcm_substream *substream)
{
        struct snd_dg00x *dg00x = substream->private_data;
        int err;

        guard(mutex)(&dg00x->mutex);

        err = snd_dg00x_stream_start_duplex(dg00x);
        if (err >= 0)
                amdtp_stream_pcm_prepare(&dg00x->tx_stream);

        return err;
}

static int pcm_playback_prepare(struct snd_pcm_substream *substream)
{
        struct snd_dg00x *dg00x = substream->private_data;
        int err;

        guard(mutex)(&dg00x->mutex);

        err = snd_dg00x_stream_start_duplex(dg00x);
        if (err >= 0) {
                amdtp_stream_pcm_prepare(&dg00x->rx_stream);
                amdtp_dot_reset(&dg00x->rx_stream);
        }

        return err;
}

static int pcm_capture_trigger(struct snd_pcm_substream *substream, int cmd)
{
        struct snd_dg00x *dg00x = substream->private_data;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
                amdtp_stream_pcm_trigger(&dg00x->tx_stream, substream);
                break;
        case SNDRV_PCM_TRIGGER_STOP:
                amdtp_stream_pcm_trigger(&dg00x->tx_stream, NULL);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int pcm_playback_trigger(struct snd_pcm_substream *substream, int cmd)
{
        struct snd_dg00x *dg00x = substream->private_data;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
                amdtp_stream_pcm_trigger(&dg00x->rx_stream, substream);
                break;
        case SNDRV_PCM_TRIGGER_STOP:
                amdtp_stream_pcm_trigger(&dg00x->rx_stream, NULL);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static snd_pcm_uframes_t pcm_capture_pointer(struct snd_pcm_substream *sbstrm)
{
        struct snd_dg00x *dg00x = sbstrm->private_data;

        return amdtp_domain_stream_pcm_pointer(&dg00x->domain, &dg00x->tx_stream);
}

static snd_pcm_uframes_t pcm_playback_pointer(struct snd_pcm_substream *sbstrm)
{
        struct snd_dg00x *dg00x = sbstrm->private_data;

        return amdtp_domain_stream_pcm_pointer(&dg00x->domain, &dg00x->rx_stream);
}

static int pcm_capture_ack(struct snd_pcm_substream *substream)
{
        struct snd_dg00x *dg00x = substream->private_data;

        return amdtp_domain_stream_pcm_ack(&dg00x->domain, &dg00x->tx_stream);
}

static int pcm_playback_ack(struct snd_pcm_substream *substream)
{
        struct snd_dg00x *dg00x = substream->private_data;

        return amdtp_domain_stream_pcm_ack(&dg00x->domain, &dg00x->rx_stream);
}

int snd_dg00x_create_pcm_devices(struct snd_dg00x *dg00x)
{
        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(dg00x->card, dg00x->card->driver, 0, 1, 1, &pcm);
        if (err < 0)
                return err;

        pcm->private_data = dg00x;
        pcm->nonatomic = true;
        snprintf(pcm->name, sizeof(pcm->name),
                 "%s PCM", dg00x->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);

        return 0;
}