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11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/moduleparam.h>
14#include <linux/console.h>
15#include <linux/notifier.h>
16
17#include <linux/selection.h>
18#include <linux/vt_kern.h>
19#include <linux/consolemap.h>
20
21#include <linux/keyboard.h>
22#include <linux/kbd_kern.h>
23#include <linux/input.h>
24
25MODULE_AUTHOR("samuel.thibault@ens-lyon.org");
26MODULE_DESCRIPTION("braille device");
27MODULE_LICENSE("GPL");
28
29
30
31
32
33
34static bool sound;
35module_param(sound, bool, 0);
36MODULE_PARM_DESC(sound, "emit sounds");
37
38static void beep(unsigned int freq)
39{
40 if (sound)
41 kd_mksound(freq, HZ/10);
42}
43
44
45#define WIDTH 40
46#define BRAILLE_KEY KEY_INSERT
47static u16 console_buf[WIDTH];
48static int console_cursor;
49
50
51static int vc_x, vc_y, lastvc_x, lastvc_y;
52
53
54static int console_show = 1;
55
56static int console_newline = 1;
57static int lastVC = -1;
58
59static struct console *braille_co;
60
61
62static void braille_write(u16 *buf)
63{
64 static u16 lastwrite[WIDTH];
65 unsigned char data[1 + 1 + 2*WIDTH + 2 + 1], csum = 0, *c;
66 u16 out;
67 int i;
68
69 if (!braille_co)
70 return;
71
72 if (!memcmp(lastwrite, buf, WIDTH * sizeof(*buf)))
73 return;
74 memcpy(lastwrite, buf, WIDTH * sizeof(*buf));
75
76#define SOH 1
77#define STX 2
78#define ETX 2
79#define EOT 4
80#define ENQ 5
81 data[0] = STX;
82 data[1] = '>';
83 csum ^= '>';
84 c = &data[2];
85 for (i = 0; i < WIDTH; i++) {
86 out = buf[i];
87 if (out >= 0x100)
88 out = '?';
89 else if (out == 0x00)
90 out = ' ';
91 csum ^= out;
92 if (out <= 0x05) {
93 *c++ = SOH;
94 out |= 0x40;
95 }
96 *c++ = out;
97 }
98
99 if (csum <= 0x05) {
100 *c++ = SOH;
101 csum |= 0x40;
102 }
103 *c++ = csum;
104 *c++ = ETX;
105
106 braille_co->write(braille_co, data, c - data);
107}
108
109
110static void vc_follow_cursor(struct vc_data *vc)
111{
112 vc_x = vc->state.x - (vc->state.x % WIDTH);
113 vc_y = vc->state.y;
114 lastvc_x = vc->state.x;
115 lastvc_y = vc->state.y;
116}
117
118
119static void vc_maybe_cursor_moved(struct vc_data *vc)
120{
121 if (vc->state.x != lastvc_x || vc->state.y != lastvc_y)
122 vc_follow_cursor(vc);
123}
124
125
126static void vc_refresh(struct vc_data *vc)
127{
128 u16 buf[WIDTH];
129 int i;
130
131 for (i = 0; i < WIDTH; i++) {
132 u16 glyph = screen_glyph(vc,
133 2 * (vc_x + i) + vc_y * vc->vc_size_row);
134 buf[i] = inverse_translate(vc, glyph, 1);
135 }
136 braille_write(buf);
137}
138
139
140
141
142
143static int keyboard_notifier_call(struct notifier_block *blk,
144 unsigned long code, void *_param)
145{
146 struct keyboard_notifier_param *param = _param;
147 struct vc_data *vc = param->vc;
148 int ret = NOTIFY_OK;
149
150 if (!param->down)
151 return ret;
152
153 switch (code) {
154 case KBD_KEYCODE:
155 if (console_show) {
156 if (param->value == BRAILLE_KEY) {
157 console_show = 0;
158 beep(880);
159 vc_maybe_cursor_moved(vc);
160 vc_refresh(vc);
161 ret = NOTIFY_STOP;
162 }
163 } else {
164 ret = NOTIFY_STOP;
165 switch (param->value) {
166 case KEY_INSERT:
167 beep(440);
168 console_show = 1;
169 lastVC = -1;
170 braille_write(console_buf);
171 break;
172 case KEY_LEFT:
173 if (vc_x > 0) {
174 vc_x -= WIDTH;
175 if (vc_x < 0)
176 vc_x = 0;
177 } else if (vc_y >= 1) {
178 beep(880);
179 vc_y--;
180 vc_x = vc->vc_cols-WIDTH;
181 } else
182 beep(220);
183 break;
184 case KEY_RIGHT:
185 if (vc_x + WIDTH < vc->vc_cols) {
186 vc_x += WIDTH;
187 } else if (vc_y + 1 < vc->vc_rows) {
188 beep(880);
189 vc_y++;
190 vc_x = 0;
191 } else
192 beep(220);
193 break;
194 case KEY_DOWN:
195 if (vc_y + 1 < vc->vc_rows)
196 vc_y++;
197 else
198 beep(220);
199 break;
200 case KEY_UP:
201 if (vc_y >= 1)
202 vc_y--;
203 else
204 beep(220);
205 break;
206 case KEY_HOME:
207 vc_follow_cursor(vc);
208 break;
209 case KEY_PAGEUP:
210 vc_x = 0;
211 vc_y = 0;
212 break;
213 case KEY_PAGEDOWN:
214 vc_x = 0;
215 vc_y = vc->vc_rows-1;
216 break;
217 default:
218 ret = NOTIFY_OK;
219 break;
220 }
221 if (ret == NOTIFY_STOP)
222 vc_refresh(vc);
223 }
224 break;
225 case KBD_POST_KEYSYM:
226 {
227 unsigned char type = KTYP(param->value) - 0xf0;
228
229 if (type == KT_SPEC) {
230 unsigned char val = KVAL(param->value);
231 int on_off = -1;
232
233 switch (val) {
234 case KVAL(K_CAPS):
235 on_off = vt_get_leds(fg_console, VC_CAPSLOCK);
236 break;
237 case KVAL(K_NUM):
238 on_off = vt_get_leds(fg_console, VC_NUMLOCK);
239 break;
240 case KVAL(K_HOLD):
241 on_off = vt_get_leds(fg_console, VC_SCROLLOCK);
242 break;
243 }
244 if (on_off == 1)
245 beep(880);
246 else if (on_off == 0)
247 beep(440);
248 }
249 }
250 break;
251 case KBD_UNBOUND_KEYCODE:
252 case KBD_UNICODE:
253 case KBD_KEYSYM:
254
255 break;
256 }
257 return ret;
258}
259
260static struct notifier_block keyboard_notifier_block = {
261 .notifier_call = keyboard_notifier_call,
262};
263
264static int vt_notifier_call(struct notifier_block *blk,
265 unsigned long code, void *_param)
266{
267 struct vt_notifier_param *param = _param;
268 struct vc_data *vc = param->vc;
269
270 switch (code) {
271 case VT_ALLOCATE:
272 break;
273 case VT_DEALLOCATE:
274 break;
275 case VT_WRITE:
276 {
277 unsigned char c = param->c;
278
279 if (vc->vc_num != fg_console)
280 break;
281 switch (c) {
282 case '\b':
283 case 127:
284 if (console_cursor > 0) {
285 console_cursor--;
286 console_buf[console_cursor] = ' ';
287 }
288 break;
289 case '\n':
290 case '\v':
291 case '\f':
292 case '\r':
293 console_newline = 1;
294 break;
295 case '\t':
296 c = ' ';
297 fallthrough;
298 default:
299 if (c < 32)
300
301 break;
302 if (console_newline) {
303 memset(console_buf, 0, sizeof(console_buf));
304 console_cursor = 0;
305 console_newline = 0;
306 }
307 if (console_cursor == WIDTH)
308 memmove(console_buf, &console_buf[1],
309 (WIDTH-1) * sizeof(*console_buf));
310 else
311 console_cursor++;
312 console_buf[console_cursor-1] = c;
313 break;
314 }
315 if (console_show)
316 braille_write(console_buf);
317 else {
318 vc_maybe_cursor_moved(vc);
319 vc_refresh(vc);
320 }
321 break;
322 }
323 case VT_UPDATE:
324
325 if (console_show) {
326 if (vc->vc_num != lastVC) {
327 lastVC = vc->vc_num;
328 memset(console_buf, 0, sizeof(console_buf));
329 console_cursor = 0;
330 braille_write(console_buf);
331 }
332 } else {
333 vc_maybe_cursor_moved(vc);
334 vc_refresh(vc);
335 }
336 break;
337 }
338 return NOTIFY_OK;
339}
340
341static struct notifier_block vt_notifier_block = {
342 .notifier_call = vt_notifier_call,
343};
344
345
346
347
348
349int braille_register_console(struct console *console, int index,
350 char *console_options, char *braille_options)
351{
352 int ret;
353
354 if (!console_options)
355
356 console_options = "57600o8";
357 if (braille_co)
358 return -ENODEV;
359 if (console->setup) {
360 ret = console->setup(console, console_options);
361 if (ret != 0)
362 return ret;
363 }
364 console->flags |= CON_ENABLED;
365 console->index = index;
366 braille_co = console;
367 register_keyboard_notifier(&keyboard_notifier_block);
368 register_vt_notifier(&vt_notifier_block);
369 return 1;
370}
371
372int braille_unregister_console(struct console *console)
373{
374 if (braille_co != console)
375 return -EINVAL;
376 unregister_keyboard_notifier(&keyboard_notifier_block);
377 unregister_vt_notifier(&vt_notifier_block);
378 braille_co = NULL;
379 return 1;
380}
381
