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1// SPDX-License-Identifier: GPL-2.0-or-later
2#include <linux/module.h>
3#include <linux/sched.h>
4#include <linux/slab.h>
5
6#include "charlcd.h"
7#include "hd44780_common.h"
8
9/* LCD commands */
10#define LCD_CMD_DISPLAY_CLEAR 0x01 /* Clear entire display */
11
12#define LCD_CMD_ENTRY_MODE 0x04 /* Set entry mode */
13#define LCD_CMD_CURSOR_INC 0x02 /* Increment cursor */
14
15#define LCD_CMD_DISPLAY_CTRL 0x08 /* Display control */
16#define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */
17#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
18#define LCD_CMD_BLINK_ON 0x01 /* Set blink on */
19
20#define LCD_CMD_SHIFT 0x10 /* Shift cursor/display */
21#define LCD_CMD_DISPLAY_SHIFT 0x08 /* Shift display instead of cursor */
22#define LCD_CMD_SHIFT_RIGHT 0x04 /* Shift display/cursor to the right */
23
24#define LCD_CMD_FUNCTION_SET 0x20 /* Set function */
25#define LCD_CMD_DATA_LEN_8BITS 0x10 /* Set data length to 8 bits */
26#define LCD_CMD_TWO_LINES 0x08 /* Set to two display lines */
27#define LCD_CMD_FONT_5X10_DOTS 0x04 /* Set char font to 5x10 dots */
28
29#define LCD_CMD_SET_CGRAM_ADDR 0x40 /* Set char generator RAM address */
30
31#define LCD_CMD_SET_DDRAM_ADDR 0x80 /* Set display data RAM address */
32
33/* sleeps that many milliseconds with a reschedule */
34static void long_sleep(int ms)
35{
36 schedule_timeout_interruptible(msecs_to_jiffies(ms));
37}
38
39int hd44780_common_print(struct charlcd *lcd, int c)
40{
41 struct hd44780_common *hdc = lcd->drvdata;
42
43 if (lcd->addr.x < hdc->bwidth) {
44 hdc->write_data(hdc, c);
45 return 0;
46 }
47
48 return 1;
49}
50EXPORT_SYMBOL_GPL(hd44780_common_print);
51
52int hd44780_common_gotoxy(struct charlcd *lcd, unsigned int x, unsigned int y)
53{
54 struct hd44780_common *hdc = lcd->drvdata;
55 unsigned int addr;
56
57 /*
58 * we force the cursor to stay at the end of the
59 * line if it wants to go farther
60 */
61 addr = x < hdc->bwidth ? x & (hdc->hwidth - 1) : hdc->bwidth - 1;
62 if (y & 1)
63 addr += hdc->hwidth;
64 if (y & 2)
65 addr += hdc->bwidth;
66 hdc->write_cmd(hdc, LCD_CMD_SET_DDRAM_ADDR | addr);
67 return 0;
68}
69EXPORT_SYMBOL_GPL(hd44780_common_gotoxy);
70
71int hd44780_common_home(struct charlcd *lcd)
72{
73 return hd44780_common_gotoxy(lcd, 0, 0);
74}
75EXPORT_SYMBOL_GPL(hd44780_common_home);
76
77/* clears the display and resets X/Y */
78int hd44780_common_clear_display(struct charlcd *lcd)
79{
80 struct hd44780_common *hdc = lcd->drvdata;
81
82 hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CLEAR);
83 /* datasheet says to wait 1,64 milliseconds */
84 long_sleep(2);
85
86 /*
87 * The Hitachi HD44780 controller (and compatible ones) reset the DDRAM
88 * address when executing the DISPLAY_CLEAR command, thus the
89 * following call is not required. However, other controllers do not
90 * (e.g. NewHaven NHD-0220DZW-AG5), thus move the cursor to home
91 * unconditionally to support both.
92 */
93 return hd44780_common_home(lcd);
94}
95EXPORT_SYMBOL_GPL(hd44780_common_clear_display);
96
97int hd44780_common_init_display(struct charlcd *lcd)
98{
99 struct hd44780_common *hdc = lcd->drvdata;
100
101 void (*write_cmd_raw)(struct hd44780_common *hdc, int cmd);
102 u8 init;
103
104 if (hdc->ifwidth != 4 && hdc->ifwidth != 8)
105 return -EINVAL;
106
107 hdc->hd44780_common_flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) |
108 LCD_FLAG_D | LCD_FLAG_C | LCD_FLAG_B;
109
110 long_sleep(20); /* wait 20 ms after power-up for the paranoid */
111
112 /*
113 * 8-bit mode, 1 line, small fonts; let's do it 3 times, to make sure
114 * the LCD is in 8-bit mode afterwards
115 */
116 init = LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS;
117 if (hdc->ifwidth == 4) {
118 init >>= 4;
119 write_cmd_raw = hdc->write_cmd_raw4;
120 } else {
121 write_cmd_raw = hdc->write_cmd;
122 }
123 write_cmd_raw(hdc, init);
124 long_sleep(10);
125 write_cmd_raw(hdc, init);
126 long_sleep(10);
127 write_cmd_raw(hdc, init);
128 long_sleep(10);
129
130 if (hdc->ifwidth == 4) {
131 /* Switch to 4-bit mode, 1 line, small fonts */
132 hdc->write_cmd_raw4(hdc, LCD_CMD_FUNCTION_SET >> 4);
133 long_sleep(10);
134 }
135
136 /* set font height and lines number */
137 hdc->write_cmd(hdc,
138 LCD_CMD_FUNCTION_SET |
139 ((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
140 ((hdc->hd44780_common_flags & LCD_FLAG_F) ?
141 LCD_CMD_FONT_5X10_DOTS : 0) |
142 ((hdc->hd44780_common_flags & LCD_FLAG_N) ?
143 LCD_CMD_TWO_LINES : 0));
144 long_sleep(10);
145
146 /* display off, cursor off, blink off */
147 hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CTRL);
148 long_sleep(10);
149
150 hdc->write_cmd(hdc,
151 LCD_CMD_DISPLAY_CTRL | /* set display mode */
152 ((hdc->hd44780_common_flags & LCD_FLAG_D) ?
153 LCD_CMD_DISPLAY_ON : 0) |
154 ((hdc->hd44780_common_flags & LCD_FLAG_C) ?
155 LCD_CMD_CURSOR_ON : 0) |
156 ((hdc->hd44780_common_flags & LCD_FLAG_B) ?
157 LCD_CMD_BLINK_ON : 0));
158
159 charlcd_backlight(lcd,
160 (hdc->hd44780_common_flags & LCD_FLAG_L) ? 1 : 0);
161
162 long_sleep(10);
163
164 /* entry mode set : increment, cursor shifting */
165 hdc->write_cmd(hdc, LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);
166
167 hd44780_common_clear_display(lcd);
168 return 0;
169}
170EXPORT_SYMBOL_GPL(hd44780_common_init_display);
171
172int hd44780_common_shift_cursor(struct charlcd *lcd, enum charlcd_shift_dir dir)
173{
174 struct hd44780_common *hdc = lcd->drvdata;
175
176 if (dir == CHARLCD_SHIFT_LEFT) {
177 /* back one char if not at end of line */
178 if (lcd->addr.x < hdc->bwidth)
179 hdc->write_cmd(hdc, LCD_CMD_SHIFT);
180 } else if (dir == CHARLCD_SHIFT_RIGHT) {
181 /* allow the cursor to pass the end of the line */
182 if (lcd->addr.x < (hdc->bwidth - 1))
183 hdc->write_cmd(hdc,
184 LCD_CMD_SHIFT | LCD_CMD_SHIFT_RIGHT);
185 }
186
187 return 0;
188}
189EXPORT_SYMBOL_GPL(hd44780_common_shift_cursor);
190
191int hd44780_common_shift_display(struct charlcd *lcd,
192 enum charlcd_shift_dir dir)
193{
194 struct hd44780_common *hdc = lcd->drvdata;
195
196 if (dir == CHARLCD_SHIFT_LEFT)
197 hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT);
198 else if (dir == CHARLCD_SHIFT_RIGHT)
199 hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT |
200 LCD_CMD_SHIFT_RIGHT);
201
202 return 0;
203}
204EXPORT_SYMBOL_GPL(hd44780_common_shift_display);
205
206static void hd44780_common_set_mode(struct hd44780_common *hdc)
207{
208 hdc->write_cmd(hdc,
209 LCD_CMD_DISPLAY_CTRL |
210 ((hdc->hd44780_common_flags & LCD_FLAG_D) ?
211 LCD_CMD_DISPLAY_ON : 0) |
212 ((hdc->hd44780_common_flags & LCD_FLAG_C) ?
213 LCD_CMD_CURSOR_ON : 0) |
214 ((hdc->hd44780_common_flags & LCD_FLAG_B) ?
215 LCD_CMD_BLINK_ON : 0));
216}
217
218int hd44780_common_display(struct charlcd *lcd, enum charlcd_onoff on)
219{
220 struct hd44780_common *hdc = lcd->drvdata;
221
222 if (on == CHARLCD_ON)
223 hdc->hd44780_common_flags |= LCD_FLAG_D;
224 else
225 hdc->hd44780_common_flags &= ~LCD_FLAG_D;
226
227 hd44780_common_set_mode(hdc);
228 return 0;
229}
230EXPORT_SYMBOL_GPL(hd44780_common_display);
231
232int hd44780_common_cursor(struct charlcd *lcd, enum charlcd_onoff on)
233{
234 struct hd44780_common *hdc = lcd->drvdata;
235
236 if (on == CHARLCD_ON)
237 hdc->hd44780_common_flags |= LCD_FLAG_C;
238 else
239 hdc->hd44780_common_flags &= ~LCD_FLAG_C;
240
241 hd44780_common_set_mode(hdc);
242 return 0;
243}
244EXPORT_SYMBOL_GPL(hd44780_common_cursor);
245
246int hd44780_common_blink(struct charlcd *lcd, enum charlcd_onoff on)
247{
248 struct hd44780_common *hdc = lcd->drvdata;
249
250 if (on == CHARLCD_ON)
251 hdc->hd44780_common_flags |= LCD_FLAG_B;
252 else
253 hdc->hd44780_common_flags &= ~LCD_FLAG_B;
254
255 hd44780_common_set_mode(hdc);
256 return 0;
257}
258EXPORT_SYMBOL_GPL(hd44780_common_blink);
259
260static void hd44780_common_set_function(struct hd44780_common *hdc)
261{
262 hdc->write_cmd(hdc,
263 LCD_CMD_FUNCTION_SET |
264 ((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
265 ((hdc->hd44780_common_flags & LCD_FLAG_F) ?
266 LCD_CMD_FONT_5X10_DOTS : 0) |
267 ((hdc->hd44780_common_flags & LCD_FLAG_N) ?
268 LCD_CMD_TWO_LINES : 0));
269}
270
271int hd44780_common_fontsize(struct charlcd *lcd, enum charlcd_fontsize size)
272{
273 struct hd44780_common *hdc = lcd->drvdata;
274
275 if (size == CHARLCD_FONTSIZE_LARGE)
276 hdc->hd44780_common_flags |= LCD_FLAG_F;
277 else
278 hdc->hd44780_common_flags &= ~LCD_FLAG_F;
279
280 hd44780_common_set_function(hdc);
281 return 0;
282}
283EXPORT_SYMBOL_GPL(hd44780_common_fontsize);
284
285int hd44780_common_lines(struct charlcd *lcd, enum charlcd_lines lines)
286{
287 struct hd44780_common *hdc = lcd->drvdata;
288
289 if (lines == CHARLCD_LINES_2)
290 hdc->hd44780_common_flags |= LCD_FLAG_N;
291 else
292 hdc->hd44780_common_flags &= ~LCD_FLAG_N;
293
294 hd44780_common_set_function(hdc);
295 return 0;
296}
297EXPORT_SYMBOL_GPL(hd44780_common_lines);
298
299int hd44780_common_redefine_char(struct charlcd *lcd, char *esc)
300{
301 /* Generator : LGcxxxxx...xx; must have <c> between '0'
302 * and '7', representing the numerical ASCII code of the
303 * redefined character, and <xx...xx> a sequence of 16
304 * hex digits representing 8 bytes for each character.
305 * Most LCDs will only use 5 lower bits of the 7 first
306 * bytes.
307 */
308
309 struct hd44780_common *hdc = lcd->drvdata;
310 unsigned char cgbytes[8];
311 unsigned char cgaddr;
312 int cgoffset;
313 int shift;
314 char value;
315 int addr;
316
317 if (!strchr(esc, ';'))
318 return 0;
319
320 esc++;
321
322 cgaddr = *(esc++) - '0';
323 if (cgaddr > 7)
324 return 1;
325
326 cgoffset = 0;
327 shift = 0;
328 value = 0;
329 while (*esc && cgoffset < 8) {
330 int half;
331
332 shift ^= 4;
333 half = hex_to_bin(*esc++);
334 if (half < 0)
335 continue;
336
337 value |= half << shift;
338 if (shift == 0) {
339 cgbytes[cgoffset++] = value;
340 value = 0;
341 }
342 }
343
344 hdc->write_cmd(hdc, LCD_CMD_SET_CGRAM_ADDR | (cgaddr * 8));
345 for (addr = 0; addr < cgoffset; addr++)
346 hdc->write_data(hdc, cgbytes[addr]);
347
348 /* ensures that we stop writing to CGRAM */
349 lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
350 return 1;
351}
352EXPORT_SYMBOL_GPL(hd44780_common_redefine_char);
353
354struct hd44780_common *hd44780_common_alloc(void)
355{
356 struct hd44780_common *hd;
357
358 hd = kzalloc(sizeof(*hd), GFP_KERNEL);
359 if (!hd)
360 return NULL;
361
362 hd->ifwidth = 8;
363 hd->bwidth = DEFAULT_LCD_BWIDTH;
364 hd->hwidth = DEFAULT_LCD_HWIDTH;
365 return hd;
366}
367EXPORT_SYMBOL_GPL(hd44780_common_alloc);
368
369MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2#include <linux/module.h>
3#include <linux/sched.h>
4#include <linux/slab.h>
5
6#include "charlcd.h"
7#include "hd44780_common.h"
8
9/* LCD commands */
10#define LCD_CMD_DISPLAY_CLEAR 0x01 /* Clear entire display */
11
12#define LCD_CMD_ENTRY_MODE 0x04 /* Set entry mode */
13#define LCD_CMD_CURSOR_INC 0x02 /* Increment cursor */
14
15#define LCD_CMD_DISPLAY_CTRL 0x08 /* Display control */
16#define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */
17#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
18#define LCD_CMD_BLINK_ON 0x01 /* Set blink on */
19
20#define LCD_CMD_SHIFT 0x10 /* Shift cursor/display */
21#define LCD_CMD_DISPLAY_SHIFT 0x08 /* Shift display instead of cursor */
22#define LCD_CMD_SHIFT_RIGHT 0x04 /* Shift display/cursor to the right */
23
24#define LCD_CMD_FUNCTION_SET 0x20 /* Set function */
25#define LCD_CMD_DATA_LEN_8BITS 0x10 /* Set data length to 8 bits */
26#define LCD_CMD_TWO_LINES 0x08 /* Set to two display lines */
27#define LCD_CMD_FONT_5X10_DOTS 0x04 /* Set char font to 5x10 dots */
28
29#define LCD_CMD_SET_CGRAM_ADDR 0x40 /* Set char generator RAM address */
30
31#define LCD_CMD_SET_DDRAM_ADDR 0x80 /* Set display data RAM address */
32
33/* sleeps that many milliseconds with a reschedule */
34static void long_sleep(int ms)
35{
36 schedule_timeout_interruptible(msecs_to_jiffies(ms));
37}
38
39int hd44780_common_print(struct charlcd *lcd, int c)
40{
41 struct hd44780_common *hdc = lcd->drvdata;
42
43 if (lcd->addr.x < hdc->bwidth) {
44 hdc->write_data(hdc, c);
45 return 0;
46 }
47
48 return 1;
49}
50EXPORT_SYMBOL_GPL(hd44780_common_print);
51
52int hd44780_common_gotoxy(struct charlcd *lcd, unsigned int x, unsigned int y)
53{
54 struct hd44780_common *hdc = lcd->drvdata;
55 unsigned int addr;
56
57 /*
58 * we force the cursor to stay at the end of the
59 * line if it wants to go farther
60 */
61 addr = x < hdc->bwidth ? x & (hdc->hwidth - 1) : hdc->bwidth - 1;
62 if (y & 1)
63 addr += hdc->hwidth;
64 if (y & 2)
65 addr += hdc->bwidth;
66 hdc->write_cmd(hdc, LCD_CMD_SET_DDRAM_ADDR | addr);
67 return 0;
68}
69EXPORT_SYMBOL_GPL(hd44780_common_gotoxy);
70
71int hd44780_common_home(struct charlcd *lcd)
72{
73 return hd44780_common_gotoxy(lcd, 0, 0);
74}
75EXPORT_SYMBOL_GPL(hd44780_common_home);
76
77/* clears the display and resets X/Y */
78int hd44780_common_clear_display(struct charlcd *lcd)
79{
80 struct hd44780_common *hdc = lcd->drvdata;
81
82 hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CLEAR);
83 /* datasheet says to wait 1,64 milliseconds */
84 long_sleep(2);
85 return 0;
86}
87EXPORT_SYMBOL_GPL(hd44780_common_clear_display);
88
89int hd44780_common_init_display(struct charlcd *lcd)
90{
91 struct hd44780_common *hdc = lcd->drvdata;
92
93 void (*write_cmd_raw)(struct hd44780_common *hdc, int cmd);
94 u8 init;
95
96 if (hdc->ifwidth != 4 && hdc->ifwidth != 8)
97 return -EINVAL;
98
99 hdc->hd44780_common_flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) |
100 LCD_FLAG_D | LCD_FLAG_C | LCD_FLAG_B;
101
102 long_sleep(20); /* wait 20 ms after power-up for the paranoid */
103
104 /*
105 * 8-bit mode, 1 line, small fonts; let's do it 3 times, to make sure
106 * the LCD is in 8-bit mode afterwards
107 */
108 init = LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS;
109 if (hdc->ifwidth == 4) {
110 init >>= 4;
111 write_cmd_raw = hdc->write_cmd_raw4;
112 } else {
113 write_cmd_raw = hdc->write_cmd;
114 }
115 write_cmd_raw(hdc, init);
116 long_sleep(10);
117 write_cmd_raw(hdc, init);
118 long_sleep(10);
119 write_cmd_raw(hdc, init);
120 long_sleep(10);
121
122 if (hdc->ifwidth == 4) {
123 /* Switch to 4-bit mode, 1 line, small fonts */
124 hdc->write_cmd_raw4(hdc, LCD_CMD_FUNCTION_SET >> 4);
125 long_sleep(10);
126 }
127
128 /* set font height and lines number */
129 hdc->write_cmd(hdc,
130 LCD_CMD_FUNCTION_SET |
131 ((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
132 ((hdc->hd44780_common_flags & LCD_FLAG_F) ?
133 LCD_CMD_FONT_5X10_DOTS : 0) |
134 ((hdc->hd44780_common_flags & LCD_FLAG_N) ?
135 LCD_CMD_TWO_LINES : 0));
136 long_sleep(10);
137
138 /* display off, cursor off, blink off */
139 hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CTRL);
140 long_sleep(10);
141
142 hdc->write_cmd(hdc,
143 LCD_CMD_DISPLAY_CTRL | /* set display mode */
144 ((hdc->hd44780_common_flags & LCD_FLAG_D) ?
145 LCD_CMD_DISPLAY_ON : 0) |
146 ((hdc->hd44780_common_flags & LCD_FLAG_C) ?
147 LCD_CMD_CURSOR_ON : 0) |
148 ((hdc->hd44780_common_flags & LCD_FLAG_B) ?
149 LCD_CMD_BLINK_ON : 0));
150
151 charlcd_backlight(lcd,
152 (hdc->hd44780_common_flags & LCD_FLAG_L) ? 1 : 0);
153
154 long_sleep(10);
155
156 /* entry mode set : increment, cursor shifting */
157 hdc->write_cmd(hdc, LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);
158
159 hd44780_common_clear_display(lcd);
160 return 0;
161}
162EXPORT_SYMBOL_GPL(hd44780_common_init_display);
163
164int hd44780_common_shift_cursor(struct charlcd *lcd, enum charlcd_shift_dir dir)
165{
166 struct hd44780_common *hdc = lcd->drvdata;
167
168 if (dir == CHARLCD_SHIFT_LEFT) {
169 /* back one char if not at end of line */
170 if (lcd->addr.x < hdc->bwidth)
171 hdc->write_cmd(hdc, LCD_CMD_SHIFT);
172 } else if (dir == CHARLCD_SHIFT_RIGHT) {
173 /* allow the cursor to pass the end of the line */
174 if (lcd->addr.x < (hdc->bwidth - 1))
175 hdc->write_cmd(hdc,
176 LCD_CMD_SHIFT | LCD_CMD_SHIFT_RIGHT);
177 }
178
179 return 0;
180}
181EXPORT_SYMBOL_GPL(hd44780_common_shift_cursor);
182
183int hd44780_common_shift_display(struct charlcd *lcd,
184 enum charlcd_shift_dir dir)
185{
186 struct hd44780_common *hdc = lcd->drvdata;
187
188 if (dir == CHARLCD_SHIFT_LEFT)
189 hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT);
190 else if (dir == CHARLCD_SHIFT_RIGHT)
191 hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT |
192 LCD_CMD_SHIFT_RIGHT);
193
194 return 0;
195}
196EXPORT_SYMBOL_GPL(hd44780_common_shift_display);
197
198static void hd44780_common_set_mode(struct hd44780_common *hdc)
199{
200 hdc->write_cmd(hdc,
201 LCD_CMD_DISPLAY_CTRL |
202 ((hdc->hd44780_common_flags & LCD_FLAG_D) ?
203 LCD_CMD_DISPLAY_ON : 0) |
204 ((hdc->hd44780_common_flags & LCD_FLAG_C) ?
205 LCD_CMD_CURSOR_ON : 0) |
206 ((hdc->hd44780_common_flags & LCD_FLAG_B) ?
207 LCD_CMD_BLINK_ON : 0));
208}
209
210int hd44780_common_display(struct charlcd *lcd, enum charlcd_onoff on)
211{
212 struct hd44780_common *hdc = lcd->drvdata;
213
214 if (on == CHARLCD_ON)
215 hdc->hd44780_common_flags |= LCD_FLAG_D;
216 else
217 hdc->hd44780_common_flags &= ~LCD_FLAG_D;
218
219 hd44780_common_set_mode(hdc);
220 return 0;
221}
222EXPORT_SYMBOL_GPL(hd44780_common_display);
223
224int hd44780_common_cursor(struct charlcd *lcd, enum charlcd_onoff on)
225{
226 struct hd44780_common *hdc = lcd->drvdata;
227
228 if (on == CHARLCD_ON)
229 hdc->hd44780_common_flags |= LCD_FLAG_C;
230 else
231 hdc->hd44780_common_flags &= ~LCD_FLAG_C;
232
233 hd44780_common_set_mode(hdc);
234 return 0;
235}
236EXPORT_SYMBOL_GPL(hd44780_common_cursor);
237
238int hd44780_common_blink(struct charlcd *lcd, enum charlcd_onoff on)
239{
240 struct hd44780_common *hdc = lcd->drvdata;
241
242 if (on == CHARLCD_ON)
243 hdc->hd44780_common_flags |= LCD_FLAG_B;
244 else
245 hdc->hd44780_common_flags &= ~LCD_FLAG_B;
246
247 hd44780_common_set_mode(hdc);
248 return 0;
249}
250EXPORT_SYMBOL_GPL(hd44780_common_blink);
251
252static void hd44780_common_set_function(struct hd44780_common *hdc)
253{
254 hdc->write_cmd(hdc,
255 LCD_CMD_FUNCTION_SET |
256 ((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
257 ((hdc->hd44780_common_flags & LCD_FLAG_F) ?
258 LCD_CMD_FONT_5X10_DOTS : 0) |
259 ((hdc->hd44780_common_flags & LCD_FLAG_N) ?
260 LCD_CMD_TWO_LINES : 0));
261}
262
263int hd44780_common_fontsize(struct charlcd *lcd, enum charlcd_fontsize size)
264{
265 struct hd44780_common *hdc = lcd->drvdata;
266
267 if (size == CHARLCD_FONTSIZE_LARGE)
268 hdc->hd44780_common_flags |= LCD_FLAG_F;
269 else
270 hdc->hd44780_common_flags &= ~LCD_FLAG_F;
271
272 hd44780_common_set_function(hdc);
273 return 0;
274}
275EXPORT_SYMBOL_GPL(hd44780_common_fontsize);
276
277int hd44780_common_lines(struct charlcd *lcd, enum charlcd_lines lines)
278{
279 struct hd44780_common *hdc = lcd->drvdata;
280
281 if (lines == CHARLCD_LINES_2)
282 hdc->hd44780_common_flags |= LCD_FLAG_N;
283 else
284 hdc->hd44780_common_flags &= ~LCD_FLAG_N;
285
286 hd44780_common_set_function(hdc);
287 return 0;
288}
289EXPORT_SYMBOL_GPL(hd44780_common_lines);
290
291int hd44780_common_redefine_char(struct charlcd *lcd, char *esc)
292{
293 /* Generator : LGcxxxxx...xx; must have <c> between '0'
294 * and '7', representing the numerical ASCII code of the
295 * redefined character, and <xx...xx> a sequence of 16
296 * hex digits representing 8 bytes for each character.
297 * Most LCDs will only use 5 lower bits of the 7 first
298 * bytes.
299 */
300
301 struct hd44780_common *hdc = lcd->drvdata;
302 unsigned char cgbytes[8];
303 unsigned char cgaddr;
304 int cgoffset;
305 int shift;
306 char value;
307 int addr;
308
309 if (!strchr(esc, ';'))
310 return 0;
311
312 esc++;
313
314 cgaddr = *(esc++) - '0';
315 if (cgaddr > 7)
316 return 1;
317
318 cgoffset = 0;
319 shift = 0;
320 value = 0;
321 while (*esc && cgoffset < 8) {
322 int half;
323
324 shift ^= 4;
325 half = hex_to_bin(*esc++);
326 if (half < 0)
327 continue;
328
329 value |= half << shift;
330 if (shift == 0) {
331 cgbytes[cgoffset++] = value;
332 value = 0;
333 }
334 }
335
336 hdc->write_cmd(hdc, LCD_CMD_SET_CGRAM_ADDR | (cgaddr * 8));
337 for (addr = 0; addr < cgoffset; addr++)
338 hdc->write_data(hdc, cgbytes[addr]);
339
340 /* ensures that we stop writing to CGRAM */
341 lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
342 return 1;
343}
344EXPORT_SYMBOL_GPL(hd44780_common_redefine_char);
345
346struct hd44780_common *hd44780_common_alloc(void)
347{
348 struct hd44780_common *hd;
349
350 hd = kzalloc(sizeof(*hd), GFP_KERNEL);
351 if (!hd)
352 return NULL;
353
354 hd->ifwidth = 8;
355 hd->bwidth = DEFAULT_LCD_BWIDTH;
356 hd->hwidth = DEFAULT_LCD_HWIDTH;
357 return hd;
358}
359EXPORT_SYMBOL_GPL(hd44780_common_alloc);
360
361MODULE_LICENSE("GPL");