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

#define READY_TIMEOUT_MS        1000

static int init_stream(struct snd_efw *efw, struct amdtp_stream *stream)
{
        struct cmp_connection *conn;
        enum cmp_direction c_dir;
        enum amdtp_stream_direction s_dir;
        int err;

        if (stream == &efw->tx_stream) {
                conn = &efw->out_conn;
                c_dir = CMP_OUTPUT;
                s_dir = AMDTP_IN_STREAM;
        } else {
                conn = &efw->in_conn;
                c_dir = CMP_INPUT;
                s_dir = AMDTP_OUT_STREAM;
        }

        err = cmp_connection_init(conn, efw->unit, c_dir, 0);
        if (err < 0)
                return err;

        err = amdtp_am824_init(stream, efw->unit, s_dir, CIP_BLOCKING | CIP_UNAWARE_SYT);
        if (err < 0) {
                amdtp_stream_destroy(stream);
                cmp_connection_destroy(conn);
                return err;
        }

        if (stream == &efw->tx_stream) {
                // Fireworks transmits NODATA packets with TAG0.
                efw->tx_stream.flags |= CIP_EMPTY_WITH_TAG0;
                // Fireworks has its own meaning for dbc.
                efw->tx_stream.flags |= CIP_DBC_IS_END_EVENT;
                // Fireworks reset dbc at bus reset.
                efw->tx_stream.flags |= CIP_SKIP_DBC_ZERO_CHECK;
                // But Recent firmwares starts packets with non-zero dbc.
                // Driver version 5.7.6 installs firmware version 5.7.3.
                if (efw->is_fireworks3 &&
                    (efw->firmware_version == 0x5070000 ||
                     efw->firmware_version == 0x5070300 ||
                     efw->firmware_version == 0x5080000))
                        efw->tx_stream.flags |= CIP_UNALIGHED_DBC;
                // AudioFire9 always reports wrong dbs. Onyx 1200F with the latest firmware (v4.6.0)
                // also report wrong dbs at 88.2 kHz or greater.
                if (efw->is_af9 || efw->firmware_version == 0x4060000)
                        efw->tx_stream.flags |= CIP_WRONG_DBS;
                // Firmware version 5.5 reports fixed interval for dbc.
                if (efw->firmware_version == 0x5050000)
                        efw->tx_stream.ctx_data.tx.dbc_interval = 8;
        }

        return err;
}

static int start_stream(struct snd_efw *efw, struct amdtp_stream *stream,
                        unsigned int rate)
{
        struct cmp_connection *conn;
        int err;

        if (stream == &efw->tx_stream)
                conn = &efw->out_conn;
        else
                conn = &efw->in_conn;

        // Establish connection via CMP.
        err = cmp_connection_establish(conn);
        if (err < 0)
                return err;

        // Start amdtp stream.
        err = amdtp_domain_add_stream(&efw->domain, stream,
                                      conn->resources.channel, conn->speed);
        if (err < 0) {
                cmp_connection_break(conn);
                return err;
        }

        return 0;
}

// This function should be called before starting the stream or after stopping
// the streams.
static void destroy_stream(struct snd_efw *efw, struct amdtp_stream *stream)
{
        amdtp_stream_destroy(stream);

        if (stream == &efw->tx_stream)
                cmp_connection_destroy(&efw->out_conn);
        else
                cmp_connection_destroy(&efw->in_conn);
}

static int
check_connection_used_by_others(struct snd_efw *efw, struct amdtp_stream *s)
{
        struct cmp_connection *conn;
        bool used;
        int err;

        if (s == &efw->tx_stream)
                conn = &efw->out_conn;
        else
                conn = &efw->in_conn;

        err = cmp_connection_check_used(conn, &used);
        if ((err >= 0) && used && !amdtp_stream_running(s)) {
                dev_err(&efw->unit->device,
                        "Connection established by others: %cPCR[%d]\n",
                        (conn->direction == CMP_OUTPUT) ? 'o' : 'i',
                        conn->pcr_index);
                err = -EBUSY;
        }

        return err;
}

int snd_efw_stream_init_duplex(struct snd_efw *efw)
{
        int err;

        err = init_stream(efw, &efw->tx_stream);
        if (err < 0)
                return err;

        err = init_stream(efw, &efw->rx_stream);
        if (err < 0) {
                destroy_stream(efw, &efw->tx_stream);
                return err;
        }

        err = amdtp_domain_init(&efw->domain);
        if (err < 0) {
                destroy_stream(efw, &efw->tx_stream);
                destroy_stream(efw, &efw->rx_stream);
                return err;
        }

        // set IEC61883 compliant mode (actually not fully compliant...).
        err = snd_efw_command_set_tx_mode(efw, SND_EFW_TRANSPORT_MODE_IEC61883);
        if (err < 0) {
                destroy_stream(efw, &efw->tx_stream);
                destroy_stream(efw, &efw->rx_stream);
        }

        return err;
}

static int keep_resources(struct snd_efw *efw, struct amdtp_stream *stream,
                          unsigned int rate, unsigned int mode)
{
        unsigned int pcm_channels;
        unsigned int midi_ports;
        struct cmp_connection *conn;
        int err;

        if (stream == &efw->tx_stream) {
                pcm_channels = efw->pcm_capture_channels[mode];
                midi_ports = efw->midi_out_ports;
                conn = &efw->out_conn;
        } else {
                pcm_channels = efw->pcm_playback_channels[mode];
                midi_ports = efw->midi_in_ports;
                conn = &efw->in_conn;
        }

        err = amdtp_am824_set_parameters(stream, rate, pcm_channels,
                                         midi_ports, false);
        if (err < 0)
                return err;

        return cmp_connection_reserve(conn, amdtp_stream_get_max_payload(stream));
}

int snd_efw_stream_reserve_duplex(struct snd_efw *efw, unsigned int rate,
                                  unsigned int frames_per_period,
                                  unsigned int frames_per_buffer)
{
        unsigned int curr_rate;
        int err;

        // Considering JACK/FFADO streaming:
        // TODO: This can be removed hwdep functionality becomes popular.
        err = check_connection_used_by_others(efw, &efw->rx_stream);
        if (err < 0)
                return err;

        // stop streams if rate is different.
        err = snd_efw_command_get_sampling_rate(efw, &curr_rate);
        if (err < 0)
                return err;
        if (rate == 0)
                rate = curr_rate;
        if (rate != curr_rate) {
                amdtp_domain_stop(&efw->domain);

                cmp_connection_break(&efw->out_conn);
                cmp_connection_break(&efw->in_conn);

                cmp_connection_release(&efw->out_conn);
                cmp_connection_release(&efw->in_conn);
        }

        if (efw->substreams_counter == 0 || rate != curr_rate) {
                unsigned int mode;

                err = snd_efw_command_set_sampling_rate(efw, rate);
                if (err < 0)
                        return err;

                err = snd_efw_get_multiplier_mode(rate, &mode);
                if (err < 0)
                        return err;

                err = keep_resources(efw, &efw->tx_stream, rate, mode);
                if (err < 0)
                        return err;

                err = keep_resources(efw, &efw->rx_stream, rate, mode);
                if (err < 0) {
                        cmp_connection_release(&efw->in_conn);
                        return err;
                }

                err = amdtp_domain_set_events_per_period(&efw->domain,
                                        frames_per_period, frames_per_buffer);
                if (err < 0) {
                        cmp_connection_release(&efw->in_conn);
                        cmp_connection_release(&efw->out_conn);
                        return err;
                }
        }

        return 0;
}

int snd_efw_stream_start_duplex(struct snd_efw *efw)
{
        unsigned int rate;
        int err = 0;

        // Need no substreams.
        if (efw->substreams_counter == 0)
                return -EIO;

        if (amdtp_streaming_error(&efw->rx_stream) ||
            amdtp_streaming_error(&efw->tx_stream)) {
                amdtp_domain_stop(&efw->domain);
                cmp_connection_break(&efw->out_conn);
                cmp_connection_break(&efw->in_conn);
        }

        err = snd_efw_command_get_sampling_rate(efw, &rate);
        if (err < 0)
                return err;

        if (!amdtp_stream_running(&efw->rx_stream)) {
                unsigned int tx_init_skip_cycles;

                // Audiofire 2/4 skip an isochronous cycle several thousands after starting
                // packet transmission.
                if (efw->is_fireworks3 && !efw->is_af9)
                        tx_init_skip_cycles = 6000;
                else
                        tx_init_skip_cycles = 0;

                err = start_stream(efw, &efw->rx_stream, rate);
                if (err < 0)
                        goto error;

                err = start_stream(efw, &efw->tx_stream, rate);
                if (err < 0)
                        goto error;

                // NOTE: The device ignores presentation time expressed by the value of syt field
                // of CIP header in received packets. The sequence of the number of data blocks per
                // packet is important for media clock recovery.
                err = amdtp_domain_start(&efw->domain, tx_init_skip_cycles, true, false);
                if (err < 0)
                        goto error;

                if (!amdtp_domain_wait_ready(&efw->domain, READY_TIMEOUT_MS)) {
                        err = -ETIMEDOUT;
                        goto error;
                }
        }

        return 0;
error:
        amdtp_domain_stop(&efw->domain);

        cmp_connection_break(&efw->out_conn);
        cmp_connection_break(&efw->in_conn);

        return err;
}

void snd_efw_stream_stop_duplex(struct snd_efw *efw)
{
        if (efw->substreams_counter == 0) {
                amdtp_domain_stop(&efw->domain);

                cmp_connection_break(&efw->out_conn);
                cmp_connection_break(&efw->in_conn);

                cmp_connection_release(&efw->out_conn);
                cmp_connection_release(&efw->in_conn);
        }
}

void snd_efw_stream_update_duplex(struct snd_efw *efw)
{
        amdtp_domain_stop(&efw->domain);

        cmp_connection_break(&efw->out_conn);
        cmp_connection_break(&efw->in_conn);

        amdtp_stream_pcm_abort(&efw->rx_stream);
        amdtp_stream_pcm_abort(&efw->tx_stream);
}

void snd_efw_stream_destroy_duplex(struct snd_efw *efw)
{
        amdtp_domain_destroy(&efw->domain);

        destroy_stream(efw, &efw->rx_stream);
        destroy_stream(efw, &efw->tx_stream);
}

void snd_efw_stream_lock_changed(struct snd_efw *efw)
{
        efw->dev_lock_changed = true;
        wake_up(&efw->hwdep_wait);
}

int snd_efw_stream_lock_try(struct snd_efw *efw)
{
        guard(spinlock_irq)(&efw->lock);

        /* user land lock this */
        if (efw->dev_lock_count < 0)
                return -EBUSY;

        /* this is the first time */
        if (efw->dev_lock_count++ == 0)
                snd_efw_stream_lock_changed(efw);
        return 0;
}

void snd_efw_stream_lock_release(struct snd_efw *efw)
{
        guard(spinlock_irq)(&efw->lock);

        if (WARN_ON(efw->dev_lock_count <= 0))
                return;
        if (--efw->dev_lock_count == 0)
                snd_efw_stream_lock_changed(efw);
}