// SPDX-License-Identifier: GPL-2.0
#include <linux/kthread.h>
#include <linux/wait.h>

#include "spk_types.h"
#include "speakup.h"
#include "spk_priv.h"

DECLARE_WAIT_QUEUE_HEAD(speakup_event);
EXPORT_SYMBOL_GPL(speakup_event);

int speakup_thread(void *data)
{
        unsigned long flags;
        int should_break;
        struct bleep our_sound;

        our_sound.active = 0;
        our_sound.freq = 0;
        our_sound.jiffies = 0;

        mutex_lock(&spk_mutex);
        while (1) {
                DEFINE_WAIT(wait);

                while (1) {
                        spin_lock_irqsave(&speakup_info.spinlock, flags);
                        our_sound = spk_unprocessed_sound;
                        spk_unprocessed_sound.active = 0;
                        prepare_to_wait(&speakup_event, &wait,
                                        TASK_INTERRUPTIBLE);
                        should_break = kthread_should_stop() ||
                                our_sound.active ||
                                (synth && synth->catch_up && synth->alive &&
                                        (speakup_info.flushing ||
                                        !synth_buffer_empty()));
                        spin_unlock_irqrestore(&speakup_info.spinlock, flags);
                        if (should_break)
                                break;
                        mutex_unlock(&spk_mutex);
                        schedule();
                        mutex_lock(&spk_mutex);
                }
                finish_wait(&speakup_event, &wait);
                if (kthread_should_stop())
                        break;

                if (our_sound.active)
                        kd_mksound(our_sound.freq, our_sound.jiffies);
                if (synth && synth->catch_up && synth->alive) {
                        /*
                         * It is up to the callee to take the lock, so that it
                         * can sleep whenever it likes
                         */
                        synth->catch_up(synth);
                }

                speakup_start_ttys();
        }
        mutex_unlock(&spk_mutex);
        return 0;
}