xref: /OK3568_Linux_fs/kernel/drivers/accessibility/speakup/thread.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun #include <linux/kthread.h>
3*4882a593Smuzhiyun #include <linux/wait.h>
4*4882a593Smuzhiyun 
5*4882a593Smuzhiyun #include "spk_types.h"
6*4882a593Smuzhiyun #include "speakup.h"
7*4882a593Smuzhiyun #include "spk_priv.h"
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun DECLARE_WAIT_QUEUE_HEAD(speakup_event);
10*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(speakup_event);
11*4882a593Smuzhiyun 
speakup_thread(void * data)12*4882a593Smuzhiyun int speakup_thread(void *data)
13*4882a593Smuzhiyun {
14*4882a593Smuzhiyun 	unsigned long flags;
15*4882a593Smuzhiyun 	int should_break;
16*4882a593Smuzhiyun 	struct bleep our_sound;
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun 	our_sound.active = 0;
19*4882a593Smuzhiyun 	our_sound.freq = 0;
20*4882a593Smuzhiyun 	our_sound.jiffies = 0;
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun 	mutex_lock(&spk_mutex);
23*4882a593Smuzhiyun 	while (1) {
24*4882a593Smuzhiyun 		DEFINE_WAIT(wait);
25*4882a593Smuzhiyun 
26*4882a593Smuzhiyun 		while (1) {
27*4882a593Smuzhiyun 			spin_lock_irqsave(&speakup_info.spinlock, flags);
28*4882a593Smuzhiyun 			our_sound = spk_unprocessed_sound;
29*4882a593Smuzhiyun 			spk_unprocessed_sound.active = 0;
30*4882a593Smuzhiyun 			prepare_to_wait(&speakup_event, &wait,
31*4882a593Smuzhiyun 					TASK_INTERRUPTIBLE);
32*4882a593Smuzhiyun 			should_break = kthread_should_stop() ||
33*4882a593Smuzhiyun 				our_sound.active ||
34*4882a593Smuzhiyun 				(synth && synth->catch_up && synth->alive &&
35*4882a593Smuzhiyun 					(speakup_info.flushing ||
36*4882a593Smuzhiyun 					!synth_buffer_empty()));
37*4882a593Smuzhiyun 			spin_unlock_irqrestore(&speakup_info.spinlock, flags);
38*4882a593Smuzhiyun 			if (should_break)
39*4882a593Smuzhiyun 				break;
40*4882a593Smuzhiyun 			mutex_unlock(&spk_mutex);
41*4882a593Smuzhiyun 			schedule();
42*4882a593Smuzhiyun 			mutex_lock(&spk_mutex);
43*4882a593Smuzhiyun 		}
44*4882a593Smuzhiyun 		finish_wait(&speakup_event, &wait);
45*4882a593Smuzhiyun 		if (kthread_should_stop())
46*4882a593Smuzhiyun 			break;
47*4882a593Smuzhiyun 
48*4882a593Smuzhiyun 		if (our_sound.active)
49*4882a593Smuzhiyun 			kd_mksound(our_sound.freq, our_sound.jiffies);
50*4882a593Smuzhiyun 		if (synth && synth->catch_up && synth->alive) {
51*4882a593Smuzhiyun 			/*
52*4882a593Smuzhiyun 			 * It is up to the callee to take the lock, so that it
53*4882a593Smuzhiyun 			 * can sleep whenever it likes
54*4882a593Smuzhiyun 			 */
55*4882a593Smuzhiyun 			synth->catch_up(synth);
56*4882a593Smuzhiyun 		}
57*4882a593Smuzhiyun 
58*4882a593Smuzhiyun 		speakup_start_ttys();
59*4882a593Smuzhiyun 	}
60*4882a593Smuzhiyun 	mutex_unlock(&spk_mutex);
61*4882a593Smuzhiyun 	return 0;
62*4882a593Smuzhiyun }
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