1351f683bSMiguel Ojeda // SPDX-License-Identifier: GPL-2.0+
239f8ea46SGeert Uytterhoeven /*
339f8ea46SGeert Uytterhoeven * Character LCD driver for Linux
439f8ea46SGeert Uytterhoeven *
539f8ea46SGeert Uytterhoeven * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
639f8ea46SGeert Uytterhoeven * Copyright (C) 2016-2017 Glider bvba
739f8ea46SGeert Uytterhoeven */
839f8ea46SGeert Uytterhoeven
939f8ea46SGeert Uytterhoeven #include <linux/atomic.h>
10b34050faSMiguel Ojeda #include <linux/ctype.h>
1139f8ea46SGeert Uytterhoeven #include <linux/fs.h>
1239f8ea46SGeert Uytterhoeven #include <linux/miscdevice.h>
1339f8ea46SGeert Uytterhoeven #include <linux/module.h>
1439f8ea46SGeert Uytterhoeven #include <linux/notifier.h>
1539f8ea46SGeert Uytterhoeven #include <linux/reboot.h>
1639f8ea46SGeert Uytterhoeven #include <linux/slab.h>
1739f8ea46SGeert Uytterhoeven #include <linux/uaccess.h>
1839f8ea46SGeert Uytterhoeven #include <linux/workqueue.h>
1939f8ea46SGeert Uytterhoeven
2039f8ea46SGeert Uytterhoeven #include <generated/utsrelease.h>
2139f8ea46SGeert Uytterhoeven
2275354284SMasahiro Yamada #include "charlcd.h"
2339f8ea46SGeert Uytterhoeven
2439f8ea46SGeert Uytterhoeven /* Keep the backlight on this many seconds for each flash */
2539f8ea46SGeert Uytterhoeven #define LCD_BL_TEMPO_PERIOD 4
2639f8ea46SGeert Uytterhoeven
2739f8ea46SGeert Uytterhoeven #define LCD_ESCAPE_LEN 24 /* Max chars for LCD escape command */
2839f8ea46SGeert Uytterhoeven #define LCD_ESCAPE_CHAR 27 /* Use char 27 for escape command */
2939f8ea46SGeert Uytterhoeven
3039f8ea46SGeert Uytterhoeven struct charlcd_priv {
3139f8ea46SGeert Uytterhoeven struct charlcd lcd;
3239f8ea46SGeert Uytterhoeven
3339f8ea46SGeert Uytterhoeven struct delayed_work bl_work;
3439f8ea46SGeert Uytterhoeven struct mutex bl_tempo_lock; /* Protects access to bl_tempo */
3539f8ea46SGeert Uytterhoeven bool bl_tempo;
3639f8ea46SGeert Uytterhoeven
3739f8ea46SGeert Uytterhoeven bool must_clear;
3839f8ea46SGeert Uytterhoeven
3939f8ea46SGeert Uytterhoeven /* contains the LCD config state */
4094047df1SLuiz Sampaio unsigned long flags;
4139f8ea46SGeert Uytterhoeven
4239f8ea46SGeert Uytterhoeven /* Current escape sequence and it's length or -1 if outside */
4339f8ea46SGeert Uytterhoeven struct {
4439f8ea46SGeert Uytterhoeven char buf[LCD_ESCAPE_LEN + 1];
4539f8ea46SGeert Uytterhoeven int len;
4639f8ea46SGeert Uytterhoeven } esc_seq;
4739f8ea46SGeert Uytterhoeven
482f920c0fSGustavo A. R. Silva unsigned long long drvdata[];
4939f8ea46SGeert Uytterhoeven };
5039f8ea46SGeert Uytterhoeven
51b658a211SAndy Shevchenko #define charlcd_to_priv(p) container_of(p, struct charlcd_priv, lcd)
5239f8ea46SGeert Uytterhoeven
5339f8ea46SGeert Uytterhoeven /* Device single-open policy control */
5439f8ea46SGeert Uytterhoeven static atomic_t charlcd_available = ATOMIC_INIT(1);
5539f8ea46SGeert Uytterhoeven
5639f8ea46SGeert Uytterhoeven /* turn the backlight on or off */
charlcd_backlight(struct charlcd * lcd,enum charlcd_onoff on)572bf82b5aSLars Poeschel void charlcd_backlight(struct charlcd *lcd, enum charlcd_onoff on)
5839f8ea46SGeert Uytterhoeven {
59b658a211SAndy Shevchenko struct charlcd_priv *priv = charlcd_to_priv(lcd);
6039f8ea46SGeert Uytterhoeven
6139f8ea46SGeert Uytterhoeven if (!lcd->ops->backlight)
6239f8ea46SGeert Uytterhoeven return;
6339f8ea46SGeert Uytterhoeven
6439f8ea46SGeert Uytterhoeven mutex_lock(&priv->bl_tempo_lock);
6539f8ea46SGeert Uytterhoeven if (!priv->bl_tempo)
6639f8ea46SGeert Uytterhoeven lcd->ops->backlight(lcd, on);
6739f8ea46SGeert Uytterhoeven mutex_unlock(&priv->bl_tempo_lock);
6839f8ea46SGeert Uytterhoeven }
692bf82b5aSLars Poeschel EXPORT_SYMBOL_GPL(charlcd_backlight);
7039f8ea46SGeert Uytterhoeven
charlcd_bl_off(struct work_struct * work)7139f8ea46SGeert Uytterhoeven static void charlcd_bl_off(struct work_struct *work)
7239f8ea46SGeert Uytterhoeven {
7339f8ea46SGeert Uytterhoeven struct delayed_work *dwork = to_delayed_work(work);
7439f8ea46SGeert Uytterhoeven struct charlcd_priv *priv =
7539f8ea46SGeert Uytterhoeven container_of(dwork, struct charlcd_priv, bl_work);
7639f8ea46SGeert Uytterhoeven
7739f8ea46SGeert Uytterhoeven mutex_lock(&priv->bl_tempo_lock);
7839f8ea46SGeert Uytterhoeven if (priv->bl_tempo) {
7939f8ea46SGeert Uytterhoeven priv->bl_tempo = false;
8039f8ea46SGeert Uytterhoeven if (!(priv->flags & LCD_FLAG_L))
81bd26b181SLars Poeschel priv->lcd.ops->backlight(&priv->lcd, CHARLCD_OFF);
8239f8ea46SGeert Uytterhoeven }
8339f8ea46SGeert Uytterhoeven mutex_unlock(&priv->bl_tempo_lock);
8439f8ea46SGeert Uytterhoeven }
8539f8ea46SGeert Uytterhoeven
8639f8ea46SGeert Uytterhoeven /* turn the backlight on for a little while */
charlcd_poke(struct charlcd * lcd)8739f8ea46SGeert Uytterhoeven void charlcd_poke(struct charlcd *lcd)
8839f8ea46SGeert Uytterhoeven {
89b658a211SAndy Shevchenko struct charlcd_priv *priv = charlcd_to_priv(lcd);
9039f8ea46SGeert Uytterhoeven
9139f8ea46SGeert Uytterhoeven if (!lcd->ops->backlight)
9239f8ea46SGeert Uytterhoeven return;
9339f8ea46SGeert Uytterhoeven
9439f8ea46SGeert Uytterhoeven cancel_delayed_work_sync(&priv->bl_work);
9539f8ea46SGeert Uytterhoeven
9639f8ea46SGeert Uytterhoeven mutex_lock(&priv->bl_tempo_lock);
9739f8ea46SGeert Uytterhoeven if (!priv->bl_tempo && !(priv->flags & LCD_FLAG_L))
98bd26b181SLars Poeschel lcd->ops->backlight(lcd, CHARLCD_ON);
9939f8ea46SGeert Uytterhoeven priv->bl_tempo = true;
10039f8ea46SGeert Uytterhoeven schedule_delayed_work(&priv->bl_work, LCD_BL_TEMPO_PERIOD * HZ);
10139f8ea46SGeert Uytterhoeven mutex_unlock(&priv->bl_tempo_lock);
10239f8ea46SGeert Uytterhoeven }
10339f8ea46SGeert Uytterhoeven EXPORT_SYMBOL_GPL(charlcd_poke);
10439f8ea46SGeert Uytterhoeven
charlcd_home(struct charlcd * lcd)10539f8ea46SGeert Uytterhoeven static void charlcd_home(struct charlcd *lcd)
10639f8ea46SGeert Uytterhoeven {
10711588b59SLars Poeschel lcd->addr.x = 0;
10811588b59SLars Poeschel lcd->addr.y = 0;
10988645a86SLars Poeschel lcd->ops->home(lcd);
11039f8ea46SGeert Uytterhoeven }
11139f8ea46SGeert Uytterhoeven
charlcd_print(struct charlcd * lcd,char c)11239f8ea46SGeert Uytterhoeven static void charlcd_print(struct charlcd *lcd, char c)
11339f8ea46SGeert Uytterhoeven {
114af9470b2SLars Poeschel if (lcd->addr.x >= lcd->width)
115af9470b2SLars Poeschel return;
116af9470b2SLars Poeschel
11739f8ea46SGeert Uytterhoeven if (lcd->char_conv)
11839f8ea46SGeert Uytterhoeven c = lcd->char_conv[(unsigned char)c];
119b26deabbSLars Poeschel
120b26deabbSLars Poeschel if (!lcd->ops->print(lcd, c))
12111588b59SLars Poeschel lcd->addr.x++;
12254bc937fSSean Young
12339f8ea46SGeert Uytterhoeven /* prevents the cursor from wrapping onto the next line */
1246e49eea3SLars Poeschel if (lcd->addr.x == lcd->width)
12540c2b72eSLars Poeschel lcd->ops->gotoxy(lcd, lcd->addr.x - 1, lcd->addr.y);
12639f8ea46SGeert Uytterhoeven }
12739f8ea46SGeert Uytterhoeven
charlcd_clear_display(struct charlcd * lcd)128377cf2cbSLars Poeschel static void charlcd_clear_display(struct charlcd *lcd)
12939f8ea46SGeert Uytterhoeven {
130377cf2cbSLars Poeschel lcd->ops->clear_display(lcd);
131377cf2cbSLars Poeschel lcd->addr.x = 0;
132377cf2cbSLars Poeschel lcd->addr.y = 0;
13339f8ea46SGeert Uytterhoeven }
13439f8ea46SGeert Uytterhoeven
13539f8ea46SGeert Uytterhoeven /*
136b34050faSMiguel Ojeda * Parses a movement command of the form "(.*);", where the group can be
137b34050faSMiguel Ojeda * any number of subcommands of the form "(x|y)[0-9]+".
138b34050faSMiguel Ojeda *
139b34050faSMiguel Ojeda * Returns whether the command is valid. The position arguments are
140b34050faSMiguel Ojeda * only written if the parsing was successful.
141b34050faSMiguel Ojeda *
142b34050faSMiguel Ojeda * For instance:
143b34050faSMiguel Ojeda * - ";" returns (<original x>, <original y>).
144b34050faSMiguel Ojeda * - "x1;" returns (1, <original y>).
145b34050faSMiguel Ojeda * - "y2x1;" returns (1, 2).
146b34050faSMiguel Ojeda * - "x12y34x56;" returns (56, 34).
147b34050faSMiguel Ojeda * - "" fails.
148b34050faSMiguel Ojeda * - "x" fails.
149b34050faSMiguel Ojeda * - "x;" fails.
150b34050faSMiguel Ojeda * - "x1" fails.
151b34050faSMiguel Ojeda * - "xy12;" fails.
152b34050faSMiguel Ojeda * - "x12yy12;" fails.
153b34050faSMiguel Ojeda * - "xx" fails.
154b34050faSMiguel Ojeda */
parse_xy(const char * s,unsigned long * x,unsigned long * y)155b34050faSMiguel Ojeda static bool parse_xy(const char *s, unsigned long *x, unsigned long *y)
156b34050faSMiguel Ojeda {
157b34050faSMiguel Ojeda unsigned long new_x = *x;
158b34050faSMiguel Ojeda unsigned long new_y = *y;
159d717e7daSAndy Shevchenko char *p;
160b34050faSMiguel Ojeda
161b34050faSMiguel Ojeda for (;;) {
162b34050faSMiguel Ojeda if (!*s)
163b34050faSMiguel Ojeda return false;
164b34050faSMiguel Ojeda
165b34050faSMiguel Ojeda if (*s == ';')
166b34050faSMiguel Ojeda break;
167b34050faSMiguel Ojeda
168b34050faSMiguel Ojeda if (*s == 'x') {
169d717e7daSAndy Shevchenko new_x = simple_strtoul(s + 1, &p, 10);
170d717e7daSAndy Shevchenko if (p == s + 1)
171b34050faSMiguel Ojeda return false;
172d717e7daSAndy Shevchenko s = p;
173b34050faSMiguel Ojeda } else if (*s == 'y') {
174d717e7daSAndy Shevchenko new_y = simple_strtoul(s + 1, &p, 10);
175d717e7daSAndy Shevchenko if (p == s + 1)
176b34050faSMiguel Ojeda return false;
177d717e7daSAndy Shevchenko s = p;
178b34050faSMiguel Ojeda } else {
179b34050faSMiguel Ojeda return false;
180b34050faSMiguel Ojeda }
181b34050faSMiguel Ojeda }
182b34050faSMiguel Ojeda
183b34050faSMiguel Ojeda *x = new_x;
184b34050faSMiguel Ojeda *y = new_y;
185b34050faSMiguel Ojeda return true;
186b34050faSMiguel Ojeda }
187b34050faSMiguel Ojeda
188b34050faSMiguel Ojeda /*
18939f8ea46SGeert Uytterhoeven * These are the file operation function for user access to /dev/lcd
19039f8ea46SGeert Uytterhoeven * This function can also be called from inside the kernel, by
19139f8ea46SGeert Uytterhoeven * setting file and ppos to NULL.
19239f8ea46SGeert Uytterhoeven *
19339f8ea46SGeert Uytterhoeven */
19439f8ea46SGeert Uytterhoeven
handle_lcd_special_code(struct charlcd * lcd)19539f8ea46SGeert Uytterhoeven static inline int handle_lcd_special_code(struct charlcd *lcd)
19639f8ea46SGeert Uytterhoeven {
197b658a211SAndy Shevchenko struct charlcd_priv *priv = charlcd_to_priv(lcd);
19839f8ea46SGeert Uytterhoeven
19939f8ea46SGeert Uytterhoeven /* LCD special codes */
20039f8ea46SGeert Uytterhoeven
20139f8ea46SGeert Uytterhoeven int processed = 0;
20239f8ea46SGeert Uytterhoeven
20339f8ea46SGeert Uytterhoeven char *esc = priv->esc_seq.buf + 2;
20439f8ea46SGeert Uytterhoeven int oldflags = priv->flags;
20539f8ea46SGeert Uytterhoeven
20639f8ea46SGeert Uytterhoeven /* check for display mode flags */
20739f8ea46SGeert Uytterhoeven switch (*esc) {
20839f8ea46SGeert Uytterhoeven case 'D': /* Display ON */
20939f8ea46SGeert Uytterhoeven priv->flags |= LCD_FLAG_D;
210d2f2187eSLars Poeschel if (priv->flags != oldflags)
211d2f2187eSLars Poeschel lcd->ops->display(lcd, CHARLCD_ON);
212d2f2187eSLars Poeschel
21339f8ea46SGeert Uytterhoeven processed = 1;
21439f8ea46SGeert Uytterhoeven break;
21539f8ea46SGeert Uytterhoeven case 'd': /* Display OFF */
21639f8ea46SGeert Uytterhoeven priv->flags &= ~LCD_FLAG_D;
217d2f2187eSLars Poeschel if (priv->flags != oldflags)
218d2f2187eSLars Poeschel lcd->ops->display(lcd, CHARLCD_OFF);
219d2f2187eSLars Poeschel
22039f8ea46SGeert Uytterhoeven processed = 1;
22139f8ea46SGeert Uytterhoeven break;
22239f8ea46SGeert Uytterhoeven case 'C': /* Cursor ON */
22339f8ea46SGeert Uytterhoeven priv->flags |= LCD_FLAG_C;
224d2f2187eSLars Poeschel if (priv->flags != oldflags)
225d2f2187eSLars Poeschel lcd->ops->cursor(lcd, CHARLCD_ON);
226d2f2187eSLars Poeschel
22739f8ea46SGeert Uytterhoeven processed = 1;
22839f8ea46SGeert Uytterhoeven break;
22939f8ea46SGeert Uytterhoeven case 'c': /* Cursor OFF */
23039f8ea46SGeert Uytterhoeven priv->flags &= ~LCD_FLAG_C;
231d2f2187eSLars Poeschel if (priv->flags != oldflags)
232d2f2187eSLars Poeschel lcd->ops->cursor(lcd, CHARLCD_OFF);
233d2f2187eSLars Poeschel
23439f8ea46SGeert Uytterhoeven processed = 1;
23539f8ea46SGeert Uytterhoeven break;
23639f8ea46SGeert Uytterhoeven case 'B': /* Blink ON */
23739f8ea46SGeert Uytterhoeven priv->flags |= LCD_FLAG_B;
238d2f2187eSLars Poeschel if (priv->flags != oldflags)
239d2f2187eSLars Poeschel lcd->ops->blink(lcd, CHARLCD_ON);
240d2f2187eSLars Poeschel
24139f8ea46SGeert Uytterhoeven processed = 1;
24239f8ea46SGeert Uytterhoeven break;
24339f8ea46SGeert Uytterhoeven case 'b': /* Blink OFF */
24439f8ea46SGeert Uytterhoeven priv->flags &= ~LCD_FLAG_B;
245d2f2187eSLars Poeschel if (priv->flags != oldflags)
246d2f2187eSLars Poeschel lcd->ops->blink(lcd, CHARLCD_OFF);
247d2f2187eSLars Poeschel
24839f8ea46SGeert Uytterhoeven processed = 1;
24939f8ea46SGeert Uytterhoeven break;
25039f8ea46SGeert Uytterhoeven case '+': /* Back light ON */
25139f8ea46SGeert Uytterhoeven priv->flags |= LCD_FLAG_L;
252a2060f28SLars Poeschel if (priv->flags != oldflags)
253a2060f28SLars Poeschel charlcd_backlight(lcd, CHARLCD_ON);
254a2060f28SLars Poeschel
25539f8ea46SGeert Uytterhoeven processed = 1;
25639f8ea46SGeert Uytterhoeven break;
25739f8ea46SGeert Uytterhoeven case '-': /* Back light OFF */
25839f8ea46SGeert Uytterhoeven priv->flags &= ~LCD_FLAG_L;
259a2060f28SLars Poeschel if (priv->flags != oldflags)
260a2060f28SLars Poeschel charlcd_backlight(lcd, CHARLCD_OFF);
261a2060f28SLars Poeschel
26239f8ea46SGeert Uytterhoeven processed = 1;
26339f8ea46SGeert Uytterhoeven break;
26439f8ea46SGeert Uytterhoeven case '*': /* Flash back light */
26539f8ea46SGeert Uytterhoeven charlcd_poke(lcd);
26639f8ea46SGeert Uytterhoeven processed = 1;
26739f8ea46SGeert Uytterhoeven break;
26839f8ea46SGeert Uytterhoeven case 'f': /* Small Font */
26939f8ea46SGeert Uytterhoeven priv->flags &= ~LCD_FLAG_F;
270d2f2187eSLars Poeschel if (priv->flags != oldflags)
271d2f2187eSLars Poeschel lcd->ops->fontsize(lcd, CHARLCD_FONTSIZE_SMALL);
272d2f2187eSLars Poeschel
27339f8ea46SGeert Uytterhoeven processed = 1;
27439f8ea46SGeert Uytterhoeven break;
27539f8ea46SGeert Uytterhoeven case 'F': /* Large Font */
27639f8ea46SGeert Uytterhoeven priv->flags |= LCD_FLAG_F;
277d2f2187eSLars Poeschel if (priv->flags != oldflags)
278d2f2187eSLars Poeschel lcd->ops->fontsize(lcd, CHARLCD_FONTSIZE_LARGE);
279d2f2187eSLars Poeschel
28039f8ea46SGeert Uytterhoeven processed = 1;
28139f8ea46SGeert Uytterhoeven break;
28239f8ea46SGeert Uytterhoeven case 'n': /* One Line */
28339f8ea46SGeert Uytterhoeven priv->flags &= ~LCD_FLAG_N;
284d2f2187eSLars Poeschel if (priv->flags != oldflags)
285d2f2187eSLars Poeschel lcd->ops->lines(lcd, CHARLCD_LINES_1);
286d2f2187eSLars Poeschel
28739f8ea46SGeert Uytterhoeven processed = 1;
28839f8ea46SGeert Uytterhoeven break;
28939f8ea46SGeert Uytterhoeven case 'N': /* Two Lines */
29039f8ea46SGeert Uytterhoeven priv->flags |= LCD_FLAG_N;
291d2f2187eSLars Poeschel if (priv->flags != oldflags)
292d2f2187eSLars Poeschel lcd->ops->lines(lcd, CHARLCD_LINES_2);
293d2f2187eSLars Poeschel
29499b9b490SRobert Abel processed = 1;
29539f8ea46SGeert Uytterhoeven break;
29639f8ea46SGeert Uytterhoeven case 'l': /* Shift Cursor Left */
29711588b59SLars Poeschel if (lcd->addr.x > 0) {
298d2f2187eSLars Poeschel if (!lcd->ops->shift_cursor(lcd, CHARLCD_SHIFT_LEFT))
29911588b59SLars Poeschel lcd->addr.x--;
30039f8ea46SGeert Uytterhoeven }
301d2f2187eSLars Poeschel
30239f8ea46SGeert Uytterhoeven processed = 1;
30339f8ea46SGeert Uytterhoeven break;
30439f8ea46SGeert Uytterhoeven case 'r': /* shift cursor right */
30511588b59SLars Poeschel if (lcd->addr.x < lcd->width) {
306d2f2187eSLars Poeschel if (!lcd->ops->shift_cursor(lcd, CHARLCD_SHIFT_RIGHT))
30711588b59SLars Poeschel lcd->addr.x++;
30839f8ea46SGeert Uytterhoeven }
309d2f2187eSLars Poeschel
31039f8ea46SGeert Uytterhoeven processed = 1;
31139f8ea46SGeert Uytterhoeven break;
31239f8ea46SGeert Uytterhoeven case 'L': /* shift display left */
313d2f2187eSLars Poeschel lcd->ops->shift_display(lcd, CHARLCD_SHIFT_LEFT);
31439f8ea46SGeert Uytterhoeven processed = 1;
31539f8ea46SGeert Uytterhoeven break;
31639f8ea46SGeert Uytterhoeven case 'R': /* shift display right */
317d2f2187eSLars Poeschel lcd->ops->shift_display(lcd, CHARLCD_SHIFT_RIGHT);
31839f8ea46SGeert Uytterhoeven processed = 1;
31939f8ea46SGeert Uytterhoeven break;
32039f8ea46SGeert Uytterhoeven case 'k': { /* kill end of line */
321b26deabbSLars Poeschel int x, xs, ys;
32239f8ea46SGeert Uytterhoeven
323b26deabbSLars Poeschel xs = lcd->addr.x;
324b26deabbSLars Poeschel ys = lcd->addr.y;
3256e49eea3SLars Poeschel for (x = lcd->addr.x; x < lcd->width; x++)
326b26deabbSLars Poeschel lcd->ops->print(lcd, ' ');
32739f8ea46SGeert Uytterhoeven
32839f8ea46SGeert Uytterhoeven /* restore cursor position */
329b26deabbSLars Poeschel lcd->addr.x = xs;
330b26deabbSLars Poeschel lcd->addr.y = ys;
33140c2b72eSLars Poeschel lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
33239f8ea46SGeert Uytterhoeven processed = 1;
33339f8ea46SGeert Uytterhoeven break;
33439f8ea46SGeert Uytterhoeven }
33539f8ea46SGeert Uytterhoeven case 'I': /* reinitialize display */
33601ec46dfSLars Poeschel lcd->ops->init_display(lcd);
33701ec46dfSLars Poeschel priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D |
33801ec46dfSLars Poeschel LCD_FLAG_C | LCD_FLAG_B;
33939f8ea46SGeert Uytterhoeven processed = 1;
34039f8ea46SGeert Uytterhoeven break;
341339acb08SLars Poeschel case 'G':
342339acb08SLars Poeschel if (lcd->ops->redefine_char)
343339acb08SLars Poeschel processed = lcd->ops->redefine_char(lcd, esc);
344339acb08SLars Poeschel else
34539f8ea46SGeert Uytterhoeven processed = 1;
34639f8ea46SGeert Uytterhoeven break;
34739f8ea46SGeert Uytterhoeven
34839f8ea46SGeert Uytterhoeven case 'x': /* gotoxy : LxXXX[yYYY]; */
34939f8ea46SGeert Uytterhoeven case 'y': /* gotoxy : LyYYY[xXXX]; */
3509bc30ab8SMans Rullgard if (priv->esc_seq.buf[priv->esc_seq.len - 1] != ';')
3519bc30ab8SMans Rullgard break;
3529bc30ab8SMans Rullgard
353b34050faSMiguel Ojeda /* If the command is valid, move to the new address */
35411588b59SLars Poeschel if (parse_xy(esc, &lcd->addr.x, &lcd->addr.y))
35540c2b72eSLars Poeschel lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
356b34050faSMiguel Ojeda
357b34050faSMiguel Ojeda /* Regardless of its validity, mark as processed */
35839f8ea46SGeert Uytterhoeven processed = 1;
35939f8ea46SGeert Uytterhoeven break;
36039f8ea46SGeert Uytterhoeven }
36139f8ea46SGeert Uytterhoeven
36239f8ea46SGeert Uytterhoeven return processed;
36339f8ea46SGeert Uytterhoeven }
36439f8ea46SGeert Uytterhoeven
charlcd_write_char(struct charlcd * lcd,char c)36539f8ea46SGeert Uytterhoeven static void charlcd_write_char(struct charlcd *lcd, char c)
36639f8ea46SGeert Uytterhoeven {
367b658a211SAndy Shevchenko struct charlcd_priv *priv = charlcd_to_priv(lcd);
36839f8ea46SGeert Uytterhoeven
36939f8ea46SGeert Uytterhoeven /* first, we'll test if we're in escape mode */
37039f8ea46SGeert Uytterhoeven if ((c != '\n') && priv->esc_seq.len >= 0) {
37139f8ea46SGeert Uytterhoeven /* yes, let's add this char to the buffer */
37239f8ea46SGeert Uytterhoeven priv->esc_seq.buf[priv->esc_seq.len++] = c;
3738c483758SRobert Abel priv->esc_seq.buf[priv->esc_seq.len] = '\0';
37439f8ea46SGeert Uytterhoeven } else {
37539f8ea46SGeert Uytterhoeven /* aborts any previous escape sequence */
37639f8ea46SGeert Uytterhoeven priv->esc_seq.len = -1;
37739f8ea46SGeert Uytterhoeven
37839f8ea46SGeert Uytterhoeven switch (c) {
37939f8ea46SGeert Uytterhoeven case LCD_ESCAPE_CHAR:
38039f8ea46SGeert Uytterhoeven /* start of an escape sequence */
38139f8ea46SGeert Uytterhoeven priv->esc_seq.len = 0;
3828c483758SRobert Abel priv->esc_seq.buf[priv->esc_seq.len] = '\0';
38339f8ea46SGeert Uytterhoeven break;
38439f8ea46SGeert Uytterhoeven case '\b':
38539f8ea46SGeert Uytterhoeven /* go back one char and clear it */
38611588b59SLars Poeschel if (lcd->addr.x > 0) {
38739f8ea46SGeert Uytterhoeven /* back one char */
388d2f2187eSLars Poeschel if (!lcd->ops->shift_cursor(lcd,
389d2f2187eSLars Poeschel CHARLCD_SHIFT_LEFT))
39011588b59SLars Poeschel lcd->addr.x--;
39139f8ea46SGeert Uytterhoeven }
39239f8ea46SGeert Uytterhoeven /* replace with a space */
393d2f2187eSLars Poeschel charlcd_print(lcd, ' ');
39439f8ea46SGeert Uytterhoeven /* back one char again */
395d2f2187eSLars Poeschel if (!lcd->ops->shift_cursor(lcd, CHARLCD_SHIFT_LEFT))
396d2f2187eSLars Poeschel lcd->addr.x--;
397d2f2187eSLars Poeschel
39839f8ea46SGeert Uytterhoeven break;
3999629cccaSRobert Abel case '\f':
40039f8ea46SGeert Uytterhoeven /* quickly clear the display */
401377cf2cbSLars Poeschel charlcd_clear_display(lcd);
40239f8ea46SGeert Uytterhoeven break;
40339f8ea46SGeert Uytterhoeven case '\n':
40439f8ea46SGeert Uytterhoeven /*
40539f8ea46SGeert Uytterhoeven * flush the remainder of the current line and
40639f8ea46SGeert Uytterhoeven * go to the beginning of the next line
40739f8ea46SGeert Uytterhoeven */
4086e49eea3SLars Poeschel for (; lcd->addr.x < lcd->width; lcd->addr.x++)
409b26deabbSLars Poeschel lcd->ops->print(lcd, ' ');
410b26deabbSLars Poeschel
41111588b59SLars Poeschel lcd->addr.x = 0;
41211588b59SLars Poeschel lcd->addr.y = (lcd->addr.y + 1) % lcd->height;
41340c2b72eSLars Poeschel lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
41439f8ea46SGeert Uytterhoeven break;
41539f8ea46SGeert Uytterhoeven case '\r':
41639f8ea46SGeert Uytterhoeven /* go to the beginning of the same line */
41711588b59SLars Poeschel lcd->addr.x = 0;
41840c2b72eSLars Poeschel lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
41939f8ea46SGeert Uytterhoeven break;
42039f8ea46SGeert Uytterhoeven case '\t':
42139f8ea46SGeert Uytterhoeven /* print a space instead of the tab */
42239f8ea46SGeert Uytterhoeven charlcd_print(lcd, ' ');
42339f8ea46SGeert Uytterhoeven break;
42439f8ea46SGeert Uytterhoeven default:
42539f8ea46SGeert Uytterhoeven /* simply print this char */
42639f8ea46SGeert Uytterhoeven charlcd_print(lcd, c);
42739f8ea46SGeert Uytterhoeven break;
42839f8ea46SGeert Uytterhoeven }
42939f8ea46SGeert Uytterhoeven }
43039f8ea46SGeert Uytterhoeven
43139f8ea46SGeert Uytterhoeven /*
43239f8ea46SGeert Uytterhoeven * now we'll see if we're in an escape mode and if the current
43339f8ea46SGeert Uytterhoeven * escape sequence can be understood.
43439f8ea46SGeert Uytterhoeven */
43539f8ea46SGeert Uytterhoeven if (priv->esc_seq.len >= 2) {
43639f8ea46SGeert Uytterhoeven int processed = 0;
43739f8ea46SGeert Uytterhoeven
43839f8ea46SGeert Uytterhoeven if (!strcmp(priv->esc_seq.buf, "[2J")) {
43939f8ea46SGeert Uytterhoeven /* clear the display */
440377cf2cbSLars Poeschel charlcd_clear_display(lcd);
44139f8ea46SGeert Uytterhoeven processed = 1;
44239f8ea46SGeert Uytterhoeven } else if (!strcmp(priv->esc_seq.buf, "[H")) {
44339f8ea46SGeert Uytterhoeven /* cursor to home */
44439f8ea46SGeert Uytterhoeven charlcd_home(lcd);
44539f8ea46SGeert Uytterhoeven processed = 1;
44639f8ea46SGeert Uytterhoeven }
44739f8ea46SGeert Uytterhoeven /* codes starting with ^[[L */
44839f8ea46SGeert Uytterhoeven else if ((priv->esc_seq.len >= 3) &&
44939f8ea46SGeert Uytterhoeven (priv->esc_seq.buf[0] == '[') &&
45039f8ea46SGeert Uytterhoeven (priv->esc_seq.buf[1] == 'L')) {
45139f8ea46SGeert Uytterhoeven processed = handle_lcd_special_code(lcd);
45239f8ea46SGeert Uytterhoeven }
45339f8ea46SGeert Uytterhoeven
45439f8ea46SGeert Uytterhoeven /* LCD special escape codes */
45539f8ea46SGeert Uytterhoeven /*
45639f8ea46SGeert Uytterhoeven * flush the escape sequence if it's been processed
45739f8ea46SGeert Uytterhoeven * or if it is getting too long.
45839f8ea46SGeert Uytterhoeven */
45939f8ea46SGeert Uytterhoeven if (processed || (priv->esc_seq.len >= LCD_ESCAPE_LEN))
46039f8ea46SGeert Uytterhoeven priv->esc_seq.len = -1;
46139f8ea46SGeert Uytterhoeven } /* escape codes */
46239f8ea46SGeert Uytterhoeven }
46339f8ea46SGeert Uytterhoeven
46439f8ea46SGeert Uytterhoeven static struct charlcd *the_charlcd;
46539f8ea46SGeert Uytterhoeven
charlcd_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)46639f8ea46SGeert Uytterhoeven static ssize_t charlcd_write(struct file *file, const char __user *buf,
46739f8ea46SGeert Uytterhoeven size_t count, loff_t *ppos)
46839f8ea46SGeert Uytterhoeven {
46939f8ea46SGeert Uytterhoeven const char __user *tmp = buf;
47039f8ea46SGeert Uytterhoeven char c;
47139f8ea46SGeert Uytterhoeven
47239f8ea46SGeert Uytterhoeven for (; count-- > 0; (*ppos)++, tmp++) {
473701454bcSSebastian Andrzej Siewior if (((count + 1) & 0x1f) == 0) {
47439f8ea46SGeert Uytterhoeven /*
475701454bcSSebastian Andrzej Siewior * charlcd_write() is invoked as a VFS->write() callback
476701454bcSSebastian Andrzej Siewior * and as such it is always invoked from preemptible
477701454bcSSebastian Andrzej Siewior * context and may sleep.
47839f8ea46SGeert Uytterhoeven */
479701454bcSSebastian Andrzej Siewior cond_resched();
480701454bcSSebastian Andrzej Siewior }
48139f8ea46SGeert Uytterhoeven
48239f8ea46SGeert Uytterhoeven if (get_user(c, tmp))
48339f8ea46SGeert Uytterhoeven return -EFAULT;
48439f8ea46SGeert Uytterhoeven
48539f8ea46SGeert Uytterhoeven charlcd_write_char(the_charlcd, c);
48639f8ea46SGeert Uytterhoeven }
48739f8ea46SGeert Uytterhoeven
48839f8ea46SGeert Uytterhoeven return tmp - buf;
48939f8ea46SGeert Uytterhoeven }
49039f8ea46SGeert Uytterhoeven
charlcd_open(struct inode * inode,struct file * file)49139f8ea46SGeert Uytterhoeven static int charlcd_open(struct inode *inode, struct file *file)
49239f8ea46SGeert Uytterhoeven {
493b658a211SAndy Shevchenko struct charlcd_priv *priv = charlcd_to_priv(the_charlcd);
49493dc1774SWilly Tarreau int ret;
49539f8ea46SGeert Uytterhoeven
49693dc1774SWilly Tarreau ret = -EBUSY;
49739f8ea46SGeert Uytterhoeven if (!atomic_dec_and_test(&charlcd_available))
49893dc1774SWilly Tarreau goto fail; /* open only once at a time */
49939f8ea46SGeert Uytterhoeven
50093dc1774SWilly Tarreau ret = -EPERM;
50139f8ea46SGeert Uytterhoeven if (file->f_mode & FMODE_READ) /* device is write-only */
50293dc1774SWilly Tarreau goto fail;
50339f8ea46SGeert Uytterhoeven
50439f8ea46SGeert Uytterhoeven if (priv->must_clear) {
50545421ffeSLars Poeschel priv->lcd.ops->clear_display(&priv->lcd);
50639f8ea46SGeert Uytterhoeven priv->must_clear = false;
50745421ffeSLars Poeschel priv->lcd.addr.x = 0;
50845421ffeSLars Poeschel priv->lcd.addr.y = 0;
50939f8ea46SGeert Uytterhoeven }
51039f8ea46SGeert Uytterhoeven return nonseekable_open(inode, file);
51193dc1774SWilly Tarreau
51293dc1774SWilly Tarreau fail:
51393dc1774SWilly Tarreau atomic_inc(&charlcd_available);
51493dc1774SWilly Tarreau return ret;
51539f8ea46SGeert Uytterhoeven }
51639f8ea46SGeert Uytterhoeven
charlcd_release(struct inode * inode,struct file * file)51739f8ea46SGeert Uytterhoeven static int charlcd_release(struct inode *inode, struct file *file)
51839f8ea46SGeert Uytterhoeven {
51939f8ea46SGeert Uytterhoeven atomic_inc(&charlcd_available);
52039f8ea46SGeert Uytterhoeven return 0;
52139f8ea46SGeert Uytterhoeven }
52239f8ea46SGeert Uytterhoeven
52339f8ea46SGeert Uytterhoeven static const struct file_operations charlcd_fops = {
52439f8ea46SGeert Uytterhoeven .write = charlcd_write,
52539f8ea46SGeert Uytterhoeven .open = charlcd_open,
52639f8ea46SGeert Uytterhoeven .release = charlcd_release,
52739f8ea46SGeert Uytterhoeven .llseek = no_llseek,
52839f8ea46SGeert Uytterhoeven };
52939f8ea46SGeert Uytterhoeven
53039f8ea46SGeert Uytterhoeven static struct miscdevice charlcd_dev = {
53139f8ea46SGeert Uytterhoeven .minor = LCD_MINOR,
53239f8ea46SGeert Uytterhoeven .name = "lcd",
53339f8ea46SGeert Uytterhoeven .fops = &charlcd_fops,
53439f8ea46SGeert Uytterhoeven };
53539f8ea46SGeert Uytterhoeven
charlcd_puts(struct charlcd * lcd,const char * s)53639f8ea46SGeert Uytterhoeven static void charlcd_puts(struct charlcd *lcd, const char *s)
53739f8ea46SGeert Uytterhoeven {
53839f8ea46SGeert Uytterhoeven const char *tmp = s;
53939f8ea46SGeert Uytterhoeven int count = strlen(s);
54039f8ea46SGeert Uytterhoeven
54139f8ea46SGeert Uytterhoeven for (; count-- > 0; tmp++) {
542701454bcSSebastian Andrzej Siewior if (((count + 1) & 0x1f) == 0)
543701454bcSSebastian Andrzej Siewior cond_resched();
54439f8ea46SGeert Uytterhoeven
54539f8ea46SGeert Uytterhoeven charlcd_write_char(lcd, *tmp);
54639f8ea46SGeert Uytterhoeven }
54739f8ea46SGeert Uytterhoeven }
54839f8ea46SGeert Uytterhoeven
549c9171722SMans Rullgard #ifdef CONFIG_PANEL_BOOT_MESSAGE
550c9171722SMans Rullgard #define LCD_INIT_TEXT CONFIG_PANEL_BOOT_MESSAGE
551c9171722SMans Rullgard #else
552c9171722SMans Rullgard #define LCD_INIT_TEXT "Linux-" UTS_RELEASE "\n"
553c9171722SMans Rullgard #endif
554c9171722SMans Rullgard
555cc5d04d8SMans Rullgard #ifdef CONFIG_CHARLCD_BL_ON
556cc5d04d8SMans Rullgard #define LCD_INIT_BL "\x1b[L+"
557cc5d04d8SMans Rullgard #elif defined(CONFIG_CHARLCD_BL_FLASH)
558cc5d04d8SMans Rullgard #define LCD_INIT_BL "\x1b[L*"
559cc5d04d8SMans Rullgard #else
560cc5d04d8SMans Rullgard #define LCD_INIT_BL "\x1b[L-"
561cc5d04d8SMans Rullgard #endif
562cc5d04d8SMans Rullgard
56339f8ea46SGeert Uytterhoeven /* initialize the LCD driver */
charlcd_init(struct charlcd * lcd)56439f8ea46SGeert Uytterhoeven static int charlcd_init(struct charlcd *lcd)
56539f8ea46SGeert Uytterhoeven {
566b658a211SAndy Shevchenko struct charlcd_priv *priv = charlcd_to_priv(lcd);
56739f8ea46SGeert Uytterhoeven int ret;
56839f8ea46SGeert Uytterhoeven
56901ec46dfSLars Poeschel priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D |
57001ec46dfSLars Poeschel LCD_FLAG_C | LCD_FLAG_B;
57139f8ea46SGeert Uytterhoeven if (lcd->ops->backlight) {
57239f8ea46SGeert Uytterhoeven mutex_init(&priv->bl_tempo_lock);
57339f8ea46SGeert Uytterhoeven INIT_DELAYED_WORK(&priv->bl_work, charlcd_bl_off);
57439f8ea46SGeert Uytterhoeven }
57539f8ea46SGeert Uytterhoeven
57639f8ea46SGeert Uytterhoeven /*
57739f8ea46SGeert Uytterhoeven * before this line, we must NOT send anything to the display.
57839f8ea46SGeert Uytterhoeven * Since charlcd_init_display() needs to write data, we have to
57939f8ea46SGeert Uytterhoeven * enable mark the LCD initialized just before.
58039f8ea46SGeert Uytterhoeven */
581*4daa9ff8SLuiz Sampaio if (WARN_ON(!lcd->ops->init_display))
582*4daa9ff8SLuiz Sampaio return -EINVAL;
583*4daa9ff8SLuiz Sampaio
58401ec46dfSLars Poeschel ret = lcd->ops->init_display(lcd);
58539f8ea46SGeert Uytterhoeven if (ret)
58639f8ea46SGeert Uytterhoeven return ret;
58739f8ea46SGeert Uytterhoeven
58839f8ea46SGeert Uytterhoeven /* display a short message */
589cc5d04d8SMans Rullgard charlcd_puts(lcd, "\x1b[Lc\x1b[Lb" LCD_INIT_BL LCD_INIT_TEXT);
590c9171722SMans Rullgard
59139f8ea46SGeert Uytterhoeven /* clear the display on the next device opening */
59239f8ea46SGeert Uytterhoeven priv->must_clear = true;
59339f8ea46SGeert Uytterhoeven charlcd_home(lcd);
59439f8ea46SGeert Uytterhoeven return 0;
59539f8ea46SGeert Uytterhoeven }
59639f8ea46SGeert Uytterhoeven
charlcd_alloc(void)5972545c1c9SLars Poeschel struct charlcd *charlcd_alloc(void)
59839f8ea46SGeert Uytterhoeven {
59939f8ea46SGeert Uytterhoeven struct charlcd_priv *priv;
60039f8ea46SGeert Uytterhoeven struct charlcd *lcd;
60139f8ea46SGeert Uytterhoeven
6022545c1c9SLars Poeschel priv = kzalloc(sizeof(*priv), GFP_KERNEL);
60339f8ea46SGeert Uytterhoeven if (!priv)
60439f8ea46SGeert Uytterhoeven return NULL;
60539f8ea46SGeert Uytterhoeven
60639f8ea46SGeert Uytterhoeven priv->esc_seq.len = -1;
60739f8ea46SGeert Uytterhoeven
60839f8ea46SGeert Uytterhoeven lcd = &priv->lcd;
60939f8ea46SGeert Uytterhoeven
61039f8ea46SGeert Uytterhoeven return lcd;
61139f8ea46SGeert Uytterhoeven }
61239f8ea46SGeert Uytterhoeven EXPORT_SYMBOL_GPL(charlcd_alloc);
61339f8ea46SGeert Uytterhoeven
charlcd_free(struct charlcd * lcd)6148e44fc85SAndy Shevchenko void charlcd_free(struct charlcd *lcd)
6158e44fc85SAndy Shevchenko {
6168e44fc85SAndy Shevchenko kfree(charlcd_to_priv(lcd));
6178e44fc85SAndy Shevchenko }
6188e44fc85SAndy Shevchenko EXPORT_SYMBOL_GPL(charlcd_free);
6198e44fc85SAndy Shevchenko
panel_notify_sys(struct notifier_block * this,unsigned long code,void * unused)62039f8ea46SGeert Uytterhoeven static int panel_notify_sys(struct notifier_block *this, unsigned long code,
62139f8ea46SGeert Uytterhoeven void *unused)
62239f8ea46SGeert Uytterhoeven {
62339f8ea46SGeert Uytterhoeven struct charlcd *lcd = the_charlcd;
62439f8ea46SGeert Uytterhoeven
62539f8ea46SGeert Uytterhoeven switch (code) {
62639f8ea46SGeert Uytterhoeven case SYS_DOWN:
62739f8ea46SGeert Uytterhoeven charlcd_puts(lcd,
62839f8ea46SGeert Uytterhoeven "\x0cReloading\nSystem...\x1b[Lc\x1b[Lb\x1b[L+");
62939f8ea46SGeert Uytterhoeven break;
63039f8ea46SGeert Uytterhoeven case SYS_HALT:
63139f8ea46SGeert Uytterhoeven charlcd_puts(lcd, "\x0cSystem Halted.\x1b[Lc\x1b[Lb\x1b[L+");
63239f8ea46SGeert Uytterhoeven break;
63339f8ea46SGeert Uytterhoeven case SYS_POWER_OFF:
63439f8ea46SGeert Uytterhoeven charlcd_puts(lcd, "\x0cPower off.\x1b[Lc\x1b[Lb\x1b[L+");
63539f8ea46SGeert Uytterhoeven break;
63639f8ea46SGeert Uytterhoeven default:
63739f8ea46SGeert Uytterhoeven break;
63839f8ea46SGeert Uytterhoeven }
63939f8ea46SGeert Uytterhoeven return NOTIFY_DONE;
64039f8ea46SGeert Uytterhoeven }
64139f8ea46SGeert Uytterhoeven
64239f8ea46SGeert Uytterhoeven static struct notifier_block panel_notifier = {
643ac8c8fa0SAndy Shevchenko .notifier_call = panel_notify_sys,
64439f8ea46SGeert Uytterhoeven };
64539f8ea46SGeert Uytterhoeven
charlcd_register(struct charlcd * lcd)64639f8ea46SGeert Uytterhoeven int charlcd_register(struct charlcd *lcd)
64739f8ea46SGeert Uytterhoeven {
64839f8ea46SGeert Uytterhoeven int ret;
64939f8ea46SGeert Uytterhoeven
65039f8ea46SGeert Uytterhoeven ret = charlcd_init(lcd);
65139f8ea46SGeert Uytterhoeven if (ret)
65239f8ea46SGeert Uytterhoeven return ret;
65339f8ea46SGeert Uytterhoeven
65439f8ea46SGeert Uytterhoeven ret = misc_register(&charlcd_dev);
65539f8ea46SGeert Uytterhoeven if (ret)
65639f8ea46SGeert Uytterhoeven return ret;
65739f8ea46SGeert Uytterhoeven
65839f8ea46SGeert Uytterhoeven the_charlcd = lcd;
65939f8ea46SGeert Uytterhoeven register_reboot_notifier(&panel_notifier);
66039f8ea46SGeert Uytterhoeven return 0;
66139f8ea46SGeert Uytterhoeven }
66239f8ea46SGeert Uytterhoeven EXPORT_SYMBOL_GPL(charlcd_register);
66339f8ea46SGeert Uytterhoeven
charlcd_unregister(struct charlcd * lcd)66439f8ea46SGeert Uytterhoeven int charlcd_unregister(struct charlcd *lcd)
66539f8ea46SGeert Uytterhoeven {
666b658a211SAndy Shevchenko struct charlcd_priv *priv = charlcd_to_priv(lcd);
66739f8ea46SGeert Uytterhoeven
66839f8ea46SGeert Uytterhoeven unregister_reboot_notifier(&panel_notifier);
66939f8ea46SGeert Uytterhoeven charlcd_puts(lcd, "\x0cLCD driver unloaded.\x1b[Lc\x1b[Lb\x1b[L-");
67039f8ea46SGeert Uytterhoeven misc_deregister(&charlcd_dev);
67139f8ea46SGeert Uytterhoeven the_charlcd = NULL;
67239f8ea46SGeert Uytterhoeven if (lcd->ops->backlight) {
67339f8ea46SGeert Uytterhoeven cancel_delayed_work_sync(&priv->bl_work);
674bd26b181SLars Poeschel priv->lcd.ops->backlight(&priv->lcd, CHARLCD_OFF);
67539f8ea46SGeert Uytterhoeven }
67639f8ea46SGeert Uytterhoeven
67739f8ea46SGeert Uytterhoeven return 0;
67839f8ea46SGeert Uytterhoeven }
67939f8ea46SGeert Uytterhoeven EXPORT_SYMBOL_GPL(charlcd_unregister);
68039f8ea46SGeert Uytterhoeven
68139f8ea46SGeert Uytterhoeven MODULE_LICENSE("GPL");
682