1// SPDX-License-Identifier: GPL-2.0
2#include <linux/kthread.h>
3#include <linux/wait.h>
4
5#include "spk_types.h"
6#include "speakup.h"
7#include "spk_priv.h"
8
9DECLARE_WAIT_QUEUE_HEAD(speakup_event);
10EXPORT_SYMBOL_GPL(speakup_event);
11
12int speakup_thread(void *data)
13{
14 unsigned long flags;
15 int should_break;
16 struct bleep our_sound;
17
18 our_sound.active = 0;
19 our_sound.freq = 0;
20 our_sound.jiffies = 0;
21
22 mutex_lock(&spk_mutex);
23 while (1) {
24 DEFINE_WAIT(wait);
25
26 while (1) {
27 spin_lock_irqsave(&speakup_info.spinlock, flags);
28 our_sound = spk_unprocessed_sound;
29 spk_unprocessed_sound.active = 0;
30 prepare_to_wait(wq_head: &speakup_event, wq_entry: &wait,
31 TASK_INTERRUPTIBLE);
32 should_break = kthread_should_stop() ||
33 our_sound.active ||
34 (synth && synth->catch_up && synth->alive &&
35 (speakup_info.flushing ||
36 !synth_buffer_empty()));
37 spin_unlock_irqrestore(lock: &speakup_info.spinlock, flags);
38 if (should_break)
39 break;
40 mutex_unlock(lock: &spk_mutex);
41 schedule();
42 mutex_lock(&spk_mutex);
43 }
44 finish_wait(wq_head: &speakup_event, wq_entry: &wait);
45 if (kthread_should_stop())
46 break;
47
48 if (our_sound.active)
49 kd_mksound(hz: our_sound.freq, ticks: our_sound.jiffies);
50 if (synth && synth->catch_up && synth->alive) {
51 /*
52 * It is up to the callee to take the lock, so that it
53 * can sleep whenever it likes
54 */
55 synth->catch_up(synth);
56 }
57
58 speakup_start_ttys();
59 }
60 mutex_unlock(lock: &spk_mutex);
61 return 0;
62}
63

source code of linux/drivers/accessibility/speakup/thread.c