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Commit | Line | Data |
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351f683b | 1 | // SPDX-License-Identifier: GPL-2.0+ |
39f8ea46 GU |
2 | /* |
3 | * Character LCD driver for Linux | |
4 | * | |
5 | * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu> | |
6 | * Copyright (C) 2016-2017 Glider bvba | |
39f8ea46 GU |
7 | */ |
8 | ||
9 | #include <linux/atomic.h> | |
b34050fa | 10 | #include <linux/ctype.h> |
39f8ea46 GU |
11 | #include <linux/fs.h> |
12 | #include <linux/miscdevice.h> | |
13 | #include <linux/module.h> | |
14 | #include <linux/notifier.h> | |
15 | #include <linux/reboot.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/uaccess.h> | |
18 | #include <linux/workqueue.h> | |
19 | ||
20 | #include <generated/utsrelease.h> | |
21 | ||
75354284 | 22 | #include "charlcd.h" |
39f8ea46 GU |
23 | |
24 | /* Keep the backlight on this many seconds for each flash */ | |
25 | #define LCD_BL_TEMPO_PERIOD 4 | |
26 | ||
39f8ea46 GU |
27 | #define LCD_ESCAPE_LEN 24 /* Max chars for LCD escape command */ |
28 | #define LCD_ESCAPE_CHAR 27 /* Use char 27 for escape command */ | |
29 | ||
30 | struct charlcd_priv { | |
31 | struct charlcd lcd; | |
32 | ||
33 | struct delayed_work bl_work; | |
34 | struct mutex bl_tempo_lock; /* Protects access to bl_tempo */ | |
35 | bool bl_tempo; | |
36 | ||
37 | bool must_clear; | |
38 | ||
39 | /* contains the LCD config state */ | |
40 | unsigned long int flags; | |
41 | ||
39f8ea46 GU |
42 | /* Current escape sequence and it's length or -1 if outside */ |
43 | struct { | |
44 | char buf[LCD_ESCAPE_LEN + 1]; | |
45 | int len; | |
46 | } esc_seq; | |
47 | ||
2f920c0f | 48 | unsigned long long drvdata[]; |
39f8ea46 GU |
49 | }; |
50 | ||
b658a211 | 51 | #define charlcd_to_priv(p) container_of(p, struct charlcd_priv, lcd) |
39f8ea46 GU |
52 | |
53 | /* Device single-open policy control */ | |
54 | static atomic_t charlcd_available = ATOMIC_INIT(1); | |
55 | ||
39f8ea46 | 56 | /* turn the backlight on or off */ |
2bf82b5a | 57 | void charlcd_backlight(struct charlcd *lcd, enum charlcd_onoff on) |
39f8ea46 | 58 | { |
b658a211 | 59 | struct charlcd_priv *priv = charlcd_to_priv(lcd); |
39f8ea46 GU |
60 | |
61 | if (!lcd->ops->backlight) | |
62 | return; | |
63 | ||
64 | mutex_lock(&priv->bl_tempo_lock); | |
65 | if (!priv->bl_tempo) | |
66 | lcd->ops->backlight(lcd, on); | |
67 | mutex_unlock(&priv->bl_tempo_lock); | |
68 | } | |
2bf82b5a | 69 | EXPORT_SYMBOL_GPL(charlcd_backlight); |
39f8ea46 GU |
70 | |
71 | static void charlcd_bl_off(struct work_struct *work) | |
72 | { | |
73 | struct delayed_work *dwork = to_delayed_work(work); | |
74 | struct charlcd_priv *priv = | |
75 | container_of(dwork, struct charlcd_priv, bl_work); | |
76 | ||
77 | mutex_lock(&priv->bl_tempo_lock); | |
78 | if (priv->bl_tempo) { | |
79 | priv->bl_tempo = false; | |
80 | if (!(priv->flags & LCD_FLAG_L)) | |
bd26b181 | 81 | priv->lcd.ops->backlight(&priv->lcd, CHARLCD_OFF); |
39f8ea46 GU |
82 | } |
83 | mutex_unlock(&priv->bl_tempo_lock); | |
84 | } | |
85 | ||
86 | /* turn the backlight on for a little while */ | |
87 | void charlcd_poke(struct charlcd *lcd) | |
88 | { | |
b658a211 | 89 | struct charlcd_priv *priv = charlcd_to_priv(lcd); |
39f8ea46 GU |
90 | |
91 | if (!lcd->ops->backlight) | |
92 | return; | |
93 | ||
94 | cancel_delayed_work_sync(&priv->bl_work); | |
95 | ||
96 | mutex_lock(&priv->bl_tempo_lock); | |
97 | if (!priv->bl_tempo && !(priv->flags & LCD_FLAG_L)) | |
bd26b181 | 98 | lcd->ops->backlight(lcd, CHARLCD_ON); |
39f8ea46 GU |
99 | priv->bl_tempo = true; |
100 | schedule_delayed_work(&priv->bl_work, LCD_BL_TEMPO_PERIOD * HZ); | |
101 | mutex_unlock(&priv->bl_tempo_lock); | |
102 | } | |
103 | EXPORT_SYMBOL_GPL(charlcd_poke); | |
104 | ||
39f8ea46 GU |
105 | static void charlcd_home(struct charlcd *lcd) |
106 | { | |
11588b59 LP |
107 | lcd->addr.x = 0; |
108 | lcd->addr.y = 0; | |
88645a86 | 109 | lcd->ops->home(lcd); |
39f8ea46 GU |
110 | } |
111 | ||
112 | static void charlcd_print(struct charlcd *lcd, char c) | |
113 | { | |
af9470b2 LP |
114 | if (lcd->addr.x >= lcd->width) |
115 | return; | |
116 | ||
b26deabb LP |
117 | if (lcd->char_conv) |
118 | c = lcd->char_conv[(unsigned char)c]; | |
39f8ea46 | 119 | |
b26deabb | 120 | if (!lcd->ops->print(lcd, c)) |
11588b59 | 121 | lcd->addr.x++; |
54bc937f | 122 | |
b26deabb | 123 | /* prevents the cursor from wrapping onto the next line */ |
6e49eea3 | 124 | if (lcd->addr.x == lcd->width) |
40c2b72e | 125 | lcd->ops->gotoxy(lcd, lcd->addr.x - 1, lcd->addr.y); |
39f8ea46 GU |
126 | } |
127 | ||
377cf2cb | 128 | static void charlcd_clear_display(struct charlcd *lcd) |
39f8ea46 | 129 | { |
377cf2cb LP |
130 | lcd->ops->clear_display(lcd); |
131 | lcd->addr.x = 0; | |
132 | lcd->addr.y = 0; | |
39f8ea46 GU |
133 | } |
134 | ||
b34050fa MO |
135 | /* |
136 | * Parses a movement command of the form "(.*);", where the group can be | |
137 | * any number of subcommands of the form "(x|y)[0-9]+". | |
138 | * | |
139 | * Returns whether the command is valid. The position arguments are | |
140 | * only written if the parsing was successful. | |
141 | * | |
142 | * For instance: | |
143 | * - ";" returns (<original x>, <original y>). | |
144 | * - "x1;" returns (1, <original y>). | |
145 | * - "y2x1;" returns (1, 2). | |
146 | * - "x12y34x56;" returns (56, 34). | |
147 | * - "" fails. | |
148 | * - "x" fails. | |
149 | * - "x;" fails. | |
150 | * - "x1" fails. | |
151 | * - "xy12;" fails. | |
152 | * - "x12yy12;" fails. | |
153 | * - "xx" fails. | |
154 | */ | |
155 | static bool parse_xy(const char *s, unsigned long *x, unsigned long *y) | |
156 | { | |
157 | unsigned long new_x = *x; | |
158 | unsigned long new_y = *y; | |
d717e7da | 159 | char *p; |
b34050fa MO |
160 | |
161 | for (;;) { | |
162 | if (!*s) | |
163 | return false; | |
164 | ||
165 | if (*s == ';') | |
166 | break; | |
167 | ||
168 | if (*s == 'x') { | |
d717e7da AS |
169 | new_x = simple_strtoul(s + 1, &p, 10); |
170 | if (p == s + 1) | |
b34050fa | 171 | return false; |
d717e7da | 172 | s = p; |
b34050fa | 173 | } else if (*s == 'y') { |
d717e7da AS |
174 | new_y = simple_strtoul(s + 1, &p, 10); |
175 | if (p == s + 1) | |
b34050fa | 176 | return false; |
d717e7da | 177 | s = p; |
b34050fa MO |
178 | } else { |
179 | return false; | |
180 | } | |
181 | } | |
182 | ||
183 | *x = new_x; | |
184 | *y = new_y; | |
185 | return true; | |
186 | } | |
187 | ||
39f8ea46 GU |
188 | /* |
189 | * These are the file operation function for user access to /dev/lcd | |
190 | * This function can also be called from inside the kernel, by | |
191 | * setting file and ppos to NULL. | |
192 | * | |
193 | */ | |
194 | ||
195 | static inline int handle_lcd_special_code(struct charlcd *lcd) | |
196 | { | |
b658a211 | 197 | struct charlcd_priv *priv = charlcd_to_priv(lcd); |
39f8ea46 GU |
198 | |
199 | /* LCD special codes */ | |
200 | ||
201 | int processed = 0; | |
202 | ||
203 | char *esc = priv->esc_seq.buf + 2; | |
204 | int oldflags = priv->flags; | |
205 | ||
206 | /* check for display mode flags */ | |
207 | switch (*esc) { | |
208 | case 'D': /* Display ON */ | |
209 | priv->flags |= LCD_FLAG_D; | |
d2f2187e LP |
210 | if (priv->flags != oldflags) |
211 | lcd->ops->display(lcd, CHARLCD_ON); | |
212 | ||
39f8ea46 GU |
213 | processed = 1; |
214 | break; | |
215 | case 'd': /* Display OFF */ | |
216 | priv->flags &= ~LCD_FLAG_D; | |
d2f2187e LP |
217 | if (priv->flags != oldflags) |
218 | lcd->ops->display(lcd, CHARLCD_OFF); | |
219 | ||
39f8ea46 GU |
220 | processed = 1; |
221 | break; | |
222 | case 'C': /* Cursor ON */ | |
223 | priv->flags |= LCD_FLAG_C; | |
d2f2187e LP |
224 | if (priv->flags != oldflags) |
225 | lcd->ops->cursor(lcd, CHARLCD_ON); | |
226 | ||
39f8ea46 GU |
227 | processed = 1; |
228 | break; | |
229 | case 'c': /* Cursor OFF */ | |
230 | priv->flags &= ~LCD_FLAG_C; | |
d2f2187e LP |
231 | if (priv->flags != oldflags) |
232 | lcd->ops->cursor(lcd, CHARLCD_OFF); | |
233 | ||
39f8ea46 GU |
234 | processed = 1; |
235 | break; | |
236 | case 'B': /* Blink ON */ | |
237 | priv->flags |= LCD_FLAG_B; | |
d2f2187e LP |
238 | if (priv->flags != oldflags) |
239 | lcd->ops->blink(lcd, CHARLCD_ON); | |
240 | ||
39f8ea46 GU |
241 | processed = 1; |
242 | break; | |
243 | case 'b': /* Blink OFF */ | |
244 | priv->flags &= ~LCD_FLAG_B; | |
d2f2187e LP |
245 | if (priv->flags != oldflags) |
246 | lcd->ops->blink(lcd, CHARLCD_OFF); | |
247 | ||
39f8ea46 GU |
248 | processed = 1; |
249 | break; | |
250 | case '+': /* Back light ON */ | |
251 | priv->flags |= LCD_FLAG_L; | |
a2060f28 LP |
252 | if (priv->flags != oldflags) |
253 | charlcd_backlight(lcd, CHARLCD_ON); | |
254 | ||
39f8ea46 GU |
255 | processed = 1; |
256 | break; | |
257 | case '-': /* Back light OFF */ | |
258 | priv->flags &= ~LCD_FLAG_L; | |
a2060f28 LP |
259 | if (priv->flags != oldflags) |
260 | charlcd_backlight(lcd, CHARLCD_OFF); | |
261 | ||
39f8ea46 GU |
262 | processed = 1; |
263 | break; | |
264 | case '*': /* Flash back light */ | |
265 | charlcd_poke(lcd); | |
266 | processed = 1; | |
267 | break; | |
268 | case 'f': /* Small Font */ | |
269 | priv->flags &= ~LCD_FLAG_F; | |
d2f2187e LP |
270 | if (priv->flags != oldflags) |
271 | lcd->ops->fontsize(lcd, CHARLCD_FONTSIZE_SMALL); | |
272 | ||
39f8ea46 GU |
273 | processed = 1; |
274 | break; | |
275 | case 'F': /* Large Font */ | |
276 | priv->flags |= LCD_FLAG_F; | |
d2f2187e LP |
277 | if (priv->flags != oldflags) |
278 | lcd->ops->fontsize(lcd, CHARLCD_FONTSIZE_LARGE); | |
279 | ||
39f8ea46 GU |
280 | processed = 1; |
281 | break; | |
282 | case 'n': /* One Line */ | |
283 | priv->flags &= ~LCD_FLAG_N; | |
d2f2187e LP |
284 | if (priv->flags != oldflags) |
285 | lcd->ops->lines(lcd, CHARLCD_LINES_1); | |
286 | ||
39f8ea46 GU |
287 | processed = 1; |
288 | break; | |
289 | case 'N': /* Two Lines */ | |
290 | priv->flags |= LCD_FLAG_N; | |
d2f2187e LP |
291 | if (priv->flags != oldflags) |
292 | lcd->ops->lines(lcd, CHARLCD_LINES_2); | |
293 | ||
99b9b490 | 294 | processed = 1; |
39f8ea46 GU |
295 | break; |
296 | case 'l': /* Shift Cursor Left */ | |
11588b59 | 297 | if (lcd->addr.x > 0) { |
d2f2187e LP |
298 | if (!lcd->ops->shift_cursor(lcd, CHARLCD_SHIFT_LEFT)) |
299 | lcd->addr.x--; | |
39f8ea46 | 300 | } |
d2f2187e | 301 | |
39f8ea46 GU |
302 | processed = 1; |
303 | break; | |
304 | case 'r': /* shift cursor right */ | |
11588b59 | 305 | if (lcd->addr.x < lcd->width) { |
d2f2187e LP |
306 | if (!lcd->ops->shift_cursor(lcd, CHARLCD_SHIFT_RIGHT)) |
307 | lcd->addr.x++; | |
39f8ea46 | 308 | } |
d2f2187e | 309 | |
39f8ea46 GU |
310 | processed = 1; |
311 | break; | |
312 | case 'L': /* shift display left */ | |
d2f2187e | 313 | lcd->ops->shift_display(lcd, CHARLCD_SHIFT_LEFT); |
39f8ea46 GU |
314 | processed = 1; |
315 | break; | |
316 | case 'R': /* shift display right */ | |
d2f2187e | 317 | lcd->ops->shift_display(lcd, CHARLCD_SHIFT_RIGHT); |
39f8ea46 GU |
318 | processed = 1; |
319 | break; | |
320 | case 'k': { /* kill end of line */ | |
b26deabb | 321 | int x, xs, ys; |
39f8ea46 | 322 | |
b26deabb LP |
323 | xs = lcd->addr.x; |
324 | ys = lcd->addr.y; | |
6e49eea3 | 325 | for (x = lcd->addr.x; x < lcd->width; x++) |
b26deabb | 326 | lcd->ops->print(lcd, ' '); |
39f8ea46 GU |
327 | |
328 | /* restore cursor position */ | |
b26deabb LP |
329 | lcd->addr.x = xs; |
330 | lcd->addr.y = ys; | |
40c2b72e | 331 | lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y); |
39f8ea46 GU |
332 | processed = 1; |
333 | break; | |
334 | } | |
335 | case 'I': /* reinitialize display */ | |
01ec46df LP |
336 | lcd->ops->init_display(lcd); |
337 | priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D | | |
338 | LCD_FLAG_C | LCD_FLAG_B; | |
39f8ea46 GU |
339 | processed = 1; |
340 | break; | |
339acb08 LP |
341 | case 'G': |
342 | if (lcd->ops->redefine_char) | |
343 | processed = lcd->ops->redefine_char(lcd, esc); | |
344 | else | |
39f8ea46 | 345 | processed = 1; |
39f8ea46 | 346 | break; |
339acb08 | 347 | |
39f8ea46 GU |
348 | case 'x': /* gotoxy : LxXXX[yYYY]; */ |
349 | case 'y': /* gotoxy : LyYYY[xXXX]; */ | |
9bc30ab8 MR |
350 | if (priv->esc_seq.buf[priv->esc_seq.len - 1] != ';') |
351 | break; | |
352 | ||
b34050fa | 353 | /* If the command is valid, move to the new address */ |
11588b59 | 354 | if (parse_xy(esc, &lcd->addr.x, &lcd->addr.y)) |
40c2b72e | 355 | lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y); |
39f8ea46 | 356 | |
b34050fa | 357 | /* Regardless of its validity, mark as processed */ |
39f8ea46 GU |
358 | processed = 1; |
359 | break; | |
360 | } | |
361 | ||
39f8ea46 GU |
362 | return processed; |
363 | } | |
364 | ||
365 | static void charlcd_write_char(struct charlcd *lcd, char c) | |
366 | { | |
b658a211 | 367 | struct charlcd_priv *priv = charlcd_to_priv(lcd); |
39f8ea46 GU |
368 | |
369 | /* first, we'll test if we're in escape mode */ | |
370 | if ((c != '\n') && priv->esc_seq.len >= 0) { | |
371 | /* yes, let's add this char to the buffer */ | |
372 | priv->esc_seq.buf[priv->esc_seq.len++] = c; | |
8c483758 | 373 | priv->esc_seq.buf[priv->esc_seq.len] = '\0'; |
39f8ea46 GU |
374 | } else { |
375 | /* aborts any previous escape sequence */ | |
376 | priv->esc_seq.len = -1; | |
377 | ||
378 | switch (c) { | |
379 | case LCD_ESCAPE_CHAR: | |
380 | /* start of an escape sequence */ | |
381 | priv->esc_seq.len = 0; | |
8c483758 | 382 | priv->esc_seq.buf[priv->esc_seq.len] = '\0'; |
39f8ea46 GU |
383 | break; |
384 | case '\b': | |
385 | /* go back one char and clear it */ | |
11588b59 | 386 | if (lcd->addr.x > 0) { |
d2f2187e LP |
387 | /* back one char */ |
388 | if (!lcd->ops->shift_cursor(lcd, | |
389 | CHARLCD_SHIFT_LEFT)) | |
390 | lcd->addr.x--; | |
39f8ea46 GU |
391 | } |
392 | /* replace with a space */ | |
d2f2187e | 393 | charlcd_print(lcd, ' '); |
39f8ea46 | 394 | /* back one char again */ |
d2f2187e LP |
395 | if (!lcd->ops->shift_cursor(lcd, CHARLCD_SHIFT_LEFT)) |
396 | lcd->addr.x--; | |
397 | ||
39f8ea46 | 398 | break; |
9629ccca | 399 | case '\f': |
39f8ea46 | 400 | /* quickly clear the display */ |
377cf2cb | 401 | charlcd_clear_display(lcd); |
39f8ea46 GU |
402 | break; |
403 | case '\n': | |
404 | /* | |
405 | * flush the remainder of the current line and | |
406 | * go to the beginning of the next line | |
407 | */ | |
6e49eea3 | 408 | for (; lcd->addr.x < lcd->width; lcd->addr.x++) |
b26deabb LP |
409 | lcd->ops->print(lcd, ' '); |
410 | ||
11588b59 LP |
411 | lcd->addr.x = 0; |
412 | lcd->addr.y = (lcd->addr.y + 1) % lcd->height; | |
40c2b72e | 413 | lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y); |
39f8ea46 GU |
414 | break; |
415 | case '\r': | |
416 | /* go to the beginning of the same line */ | |
11588b59 | 417 | lcd->addr.x = 0; |
40c2b72e | 418 | lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y); |
39f8ea46 GU |
419 | break; |
420 | case '\t': | |
421 | /* print a space instead of the tab */ | |
422 | charlcd_print(lcd, ' '); | |
423 | break; | |
424 | default: | |
425 | /* simply print this char */ | |
426 | charlcd_print(lcd, c); | |
427 | break; | |
428 | } | |
429 | } | |
430 | ||
431 | /* | |
432 | * now we'll see if we're in an escape mode and if the current | |
433 | * escape sequence can be understood. | |
434 | */ | |
435 | if (priv->esc_seq.len >= 2) { | |
436 | int processed = 0; | |
437 | ||
438 | if (!strcmp(priv->esc_seq.buf, "[2J")) { | |
439 | /* clear the display */ | |
377cf2cb | 440 | charlcd_clear_display(lcd); |
39f8ea46 GU |
441 | processed = 1; |
442 | } else if (!strcmp(priv->esc_seq.buf, "[H")) { | |
443 | /* cursor to home */ | |
444 | charlcd_home(lcd); | |
445 | processed = 1; | |
446 | } | |
447 | /* codes starting with ^[[L */ | |
448 | else if ((priv->esc_seq.len >= 3) && | |
449 | (priv->esc_seq.buf[0] == '[') && | |
450 | (priv->esc_seq.buf[1] == 'L')) { | |
451 | processed = handle_lcd_special_code(lcd); | |
452 | } | |
453 | ||
454 | /* LCD special escape codes */ | |
455 | /* | |
456 | * flush the escape sequence if it's been processed | |
457 | * or if it is getting too long. | |
458 | */ | |
459 | if (processed || (priv->esc_seq.len >= LCD_ESCAPE_LEN)) | |
460 | priv->esc_seq.len = -1; | |
461 | } /* escape codes */ | |
462 | } | |
463 | ||
464 | static struct charlcd *the_charlcd; | |
465 | ||
466 | static ssize_t charlcd_write(struct file *file, const char __user *buf, | |
467 | size_t count, loff_t *ppos) | |
468 | { | |
469 | const char __user *tmp = buf; | |
470 | char c; | |
471 | ||
472 | for (; count-- > 0; (*ppos)++, tmp++) { | |
473 | if (!in_interrupt() && (((count + 1) & 0x1f) == 0)) | |
474 | /* | |
475 | * let's be a little nice with other processes | |
476 | * that need some CPU | |
477 | */ | |
478 | schedule(); | |
479 | ||
480 | if (get_user(c, tmp)) | |
481 | return -EFAULT; | |
482 | ||
483 | charlcd_write_char(the_charlcd, c); | |
484 | } | |
485 | ||
486 | return tmp - buf; | |
487 | } | |
488 | ||
489 | static int charlcd_open(struct inode *inode, struct file *file) | |
490 | { | |
b658a211 | 491 | struct charlcd_priv *priv = charlcd_to_priv(the_charlcd); |
93dc1774 | 492 | int ret; |
39f8ea46 | 493 | |
93dc1774 | 494 | ret = -EBUSY; |
39f8ea46 | 495 | if (!atomic_dec_and_test(&charlcd_available)) |
93dc1774 | 496 | goto fail; /* open only once at a time */ |
39f8ea46 | 497 | |
93dc1774 | 498 | ret = -EPERM; |
39f8ea46 | 499 | if (file->f_mode & FMODE_READ) /* device is write-only */ |
93dc1774 | 500 | goto fail; |
39f8ea46 GU |
501 | |
502 | if (priv->must_clear) { | |
45421ffe | 503 | priv->lcd.ops->clear_display(&priv->lcd); |
39f8ea46 | 504 | priv->must_clear = false; |
45421ffe LP |
505 | priv->lcd.addr.x = 0; |
506 | priv->lcd.addr.y = 0; | |
39f8ea46 GU |
507 | } |
508 | return nonseekable_open(inode, file); | |
93dc1774 WT |
509 | |
510 | fail: | |
511 | atomic_inc(&charlcd_available); | |
512 | return ret; | |
39f8ea46 GU |
513 | } |
514 | ||
515 | static int charlcd_release(struct inode *inode, struct file *file) | |
516 | { | |
517 | atomic_inc(&charlcd_available); | |
518 | return 0; | |
519 | } | |
520 | ||
521 | static const struct file_operations charlcd_fops = { | |
522 | .write = charlcd_write, | |
523 | .open = charlcd_open, | |
524 | .release = charlcd_release, | |
525 | .llseek = no_llseek, | |
526 | }; | |
527 | ||
528 | static struct miscdevice charlcd_dev = { | |
529 | .minor = LCD_MINOR, | |
530 | .name = "lcd", | |
531 | .fops = &charlcd_fops, | |
532 | }; | |
533 | ||
534 | static void charlcd_puts(struct charlcd *lcd, const char *s) | |
535 | { | |
536 | const char *tmp = s; | |
537 | int count = strlen(s); | |
538 | ||
539 | for (; count-- > 0; tmp++) { | |
540 | if (!in_interrupt() && (((count + 1) & 0x1f) == 0)) | |
541 | /* | |
542 | * let's be a little nice with other processes | |
543 | * that need some CPU | |
544 | */ | |
545 | schedule(); | |
546 | ||
547 | charlcd_write_char(lcd, *tmp); | |
548 | } | |
549 | } | |
550 | ||
c9171722 MR |
551 | #ifdef CONFIG_PANEL_BOOT_MESSAGE |
552 | #define LCD_INIT_TEXT CONFIG_PANEL_BOOT_MESSAGE | |
553 | #else | |
554 | #define LCD_INIT_TEXT "Linux-" UTS_RELEASE "\n" | |
555 | #endif | |
556 | ||
cc5d04d8 MR |
557 | #ifdef CONFIG_CHARLCD_BL_ON |
558 | #define LCD_INIT_BL "\x1b[L+" | |
559 | #elif defined(CONFIG_CHARLCD_BL_FLASH) | |
560 | #define LCD_INIT_BL "\x1b[L*" | |
561 | #else | |
562 | #define LCD_INIT_BL "\x1b[L-" | |
563 | #endif | |
564 | ||
39f8ea46 GU |
565 | /* initialize the LCD driver */ |
566 | static int charlcd_init(struct charlcd *lcd) | |
567 | { | |
b658a211 | 568 | struct charlcd_priv *priv = charlcd_to_priv(lcd); |
39f8ea46 GU |
569 | int ret; |
570 | ||
01ec46df LP |
571 | priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D | |
572 | LCD_FLAG_C | LCD_FLAG_B; | |
39f8ea46 GU |
573 | if (lcd->ops->backlight) { |
574 | mutex_init(&priv->bl_tempo_lock); | |
575 | INIT_DELAYED_WORK(&priv->bl_work, charlcd_bl_off); | |
576 | } | |
577 | ||
578 | /* | |
579 | * before this line, we must NOT send anything to the display. | |
580 | * Since charlcd_init_display() needs to write data, we have to | |
581 | * enable mark the LCD initialized just before. | |
582 | */ | |
01ec46df | 583 | ret = lcd->ops->init_display(lcd); |
39f8ea46 GU |
584 | if (ret) |
585 | return ret; | |
586 | ||
587 | /* display a short message */ | |
cc5d04d8 | 588 | charlcd_puts(lcd, "\x1b[Lc\x1b[Lb" LCD_INIT_BL LCD_INIT_TEXT); |
c9171722 | 589 | |
39f8ea46 GU |
590 | /* clear the display on the next device opening */ |
591 | priv->must_clear = true; | |
592 | charlcd_home(lcd); | |
593 | return 0; | |
594 | } | |
595 | ||
2545c1c9 | 596 | struct charlcd *charlcd_alloc(void) |
39f8ea46 GU |
597 | { |
598 | struct charlcd_priv *priv; | |
599 | struct charlcd *lcd; | |
600 | ||
2545c1c9 | 601 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); |
39f8ea46 GU |
602 | if (!priv) |
603 | return NULL; | |
604 | ||
605 | priv->esc_seq.len = -1; | |
606 | ||
607 | lcd = &priv->lcd; | |
39f8ea46 GU |
608 | |
609 | return lcd; | |
610 | } | |
611 | EXPORT_SYMBOL_GPL(charlcd_alloc); | |
612 | ||
8e44fc85 AS |
613 | void charlcd_free(struct charlcd *lcd) |
614 | { | |
615 | kfree(charlcd_to_priv(lcd)); | |
616 | } | |
617 | EXPORT_SYMBOL_GPL(charlcd_free); | |
618 | ||
39f8ea46 GU |
619 | static int panel_notify_sys(struct notifier_block *this, unsigned long code, |
620 | void *unused) | |
621 | { | |
622 | struct charlcd *lcd = the_charlcd; | |
623 | ||
624 | switch (code) { | |
625 | case SYS_DOWN: | |
626 | charlcd_puts(lcd, | |
627 | "\x0cReloading\nSystem...\x1b[Lc\x1b[Lb\x1b[L+"); | |
628 | break; | |
629 | case SYS_HALT: | |
630 | charlcd_puts(lcd, "\x0cSystem Halted.\x1b[Lc\x1b[Lb\x1b[L+"); | |
631 | break; | |
632 | case SYS_POWER_OFF: | |
633 | charlcd_puts(lcd, "\x0cPower off.\x1b[Lc\x1b[Lb\x1b[L+"); | |
634 | break; | |
635 | default: | |
636 | break; | |
637 | } | |
638 | return NOTIFY_DONE; | |
639 | } | |
640 | ||
641 | static struct notifier_block panel_notifier = { | |
642 | panel_notify_sys, | |
643 | NULL, | |
644 | 0 | |
645 | }; | |
646 | ||
647 | int charlcd_register(struct charlcd *lcd) | |
648 | { | |
649 | int ret; | |
650 | ||
651 | ret = charlcd_init(lcd); | |
652 | if (ret) | |
653 | return ret; | |
654 | ||
655 | ret = misc_register(&charlcd_dev); | |
656 | if (ret) | |
657 | return ret; | |
658 | ||
659 | the_charlcd = lcd; | |
660 | register_reboot_notifier(&panel_notifier); | |
661 | return 0; | |
662 | } | |
663 | EXPORT_SYMBOL_GPL(charlcd_register); | |
664 | ||
665 | int charlcd_unregister(struct charlcd *lcd) | |
666 | { | |
b658a211 | 667 | struct charlcd_priv *priv = charlcd_to_priv(lcd); |
39f8ea46 GU |
668 | |
669 | unregister_reboot_notifier(&panel_notifier); | |
670 | charlcd_puts(lcd, "\x0cLCD driver unloaded.\x1b[Lc\x1b[Lb\x1b[L-"); | |
671 | misc_deregister(&charlcd_dev); | |
672 | the_charlcd = NULL; | |
673 | if (lcd->ops->backlight) { | |
674 | cancel_delayed_work_sync(&priv->bl_work); | |
bd26b181 | 675 | priv->lcd.ops->backlight(&priv->lcd, CHARLCD_OFF); |
39f8ea46 GU |
676 | } |
677 | ||
678 | return 0; | |
679 | } | |
680 | EXPORT_SYMBOL_GPL(charlcd_unregister); | |
681 | ||
682 | MODULE_LICENSE("GPL"); |