1 /* fakekey.c
2 * Functions for simulating keypresses.
3 *
4 * Copyright (C) 2010 the Speakup Team
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20 #include <linux/types.h>
21 #include <linux/slab.h>
22 #include <linux/preempt.h>
23 #include <linux/percpu.h>
24 #include <linux/input.h>
25
26 #include "speakup.h"
27
28 #define PRESSED 1
29 #define RELEASED 0
30
31 DEFINE_PER_CPU(bool, reporting_keystroke);
32
33 static struct input_dev *virt_keyboard;
34
speakup_add_virtual_keyboard(void)35 int speakup_add_virtual_keyboard(void)
36 {
37 int err;
38
39 virt_keyboard = input_allocate_device();
40
41 if (!virt_keyboard)
42 return -ENOMEM;
43
44 virt_keyboard->name = "Speakup";
45 virt_keyboard->id.bustype = BUS_VIRTUAL;
46 virt_keyboard->phys = "speakup/input0";
47 virt_keyboard->dev.parent = NULL;
48
49 __set_bit(EV_KEY, virt_keyboard->evbit);
50 __set_bit(KEY_DOWN, virt_keyboard->keybit);
51
52 err = input_register_device(virt_keyboard);
53 if (err) {
54 input_free_device(virt_keyboard);
55 virt_keyboard = NULL;
56 }
57
58 return err;
59 }
60
speakup_remove_virtual_keyboard(void)61 void speakup_remove_virtual_keyboard(void)
62 {
63 if (virt_keyboard != NULL) {
64 input_unregister_device(virt_keyboard);
65 virt_keyboard = NULL;
66 }
67 }
68
69 /*
70 * Send a simulated down-arrow to the application.
71 */
speakup_fake_down_arrow(void)72 void speakup_fake_down_arrow(void)
73 {
74 unsigned long flags;
75
76 /* disable keyboard interrupts */
77 local_irq_save(flags);
78 /* don't change CPU */
79 preempt_disable();
80
81 __this_cpu_write(reporting_keystroke, true);
82 input_report_key(virt_keyboard, KEY_DOWN, PRESSED);
83 input_report_key(virt_keyboard, KEY_DOWN, RELEASED);
84 __this_cpu_write(reporting_keystroke, false);
85
86 /* reenable preemption */
87 preempt_enable();
88 /* reenable keyboard interrupts */
89 local_irq_restore(flags);
90 }
91
92 /*
93 * Are we handling a simulated keypress on the current CPU?
94 * Returns a boolean.
95 */
speakup_fake_key_pressed(void)96 bool speakup_fake_key_pressed(void)
97 {
98 return this_cpu_read(reporting_keystroke);
99 }
100