Commit | Line | Data |
---|---|---|
718e05ed LP |
1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | #include <linux/module.h> | |
45421ffe | 3 | #include <linux/sched.h> |
718e05ed LP |
4 | #include <linux/slab.h> |
5 | ||
b26deabb | 6 | #include "charlcd.h" |
718e05ed LP |
7 | #include "hd44780_common.h" |
8 | ||
d3a2fb81 | 9 | /* LCD commands */ |
45421ffe LP |
10 | #define LCD_CMD_DISPLAY_CLEAR 0x01 /* Clear entire display */ |
11 | ||
01ec46df LP |
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 | ||
d2f2187e LP |
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 | ||
01ec46df LP |
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 | ||
339acb08 LP |
29 | #define LCD_CMD_SET_CGRAM_ADDR 0x40 /* Set char generator RAM address */ |
30 | ||
d3a2fb81 LP |
31 | #define LCD_CMD_SET_DDRAM_ADDR 0x80 /* Set display data RAM address */ |
32 | ||
45421ffe LP |
33 | /* sleeps that many milliseconds with a reschedule */ |
34 | static void long_sleep(int ms) | |
35 | { | |
36 | schedule_timeout_interruptible(msecs_to_jiffies(ms)); | |
37 | } | |
38 | ||
b26deabb LP |
39 | int 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 | } | |
50 | EXPORT_SYMBOL_GPL(hd44780_common_print); | |
51 | ||
40c2b72e | 52 | int hd44780_common_gotoxy(struct charlcd *lcd, unsigned int x, unsigned int y) |
d3a2fb81 LP |
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 | */ | |
40c2b72e LP |
61 | addr = x < hdc->bwidth ? x & (hdc->hwidth - 1) : hdc->bwidth - 1; |
62 | if (y & 1) | |
d3a2fb81 | 63 | addr += hdc->hwidth; |
40c2b72e | 64 | if (y & 2) |
d3a2fb81 LP |
65 | addr += hdc->bwidth; |
66 | hdc->write_cmd(hdc, LCD_CMD_SET_DDRAM_ADDR | addr); | |
67 | return 0; | |
68 | } | |
69 | EXPORT_SYMBOL_GPL(hd44780_common_gotoxy); | |
70 | ||
88645a86 LP |
71 | int hd44780_common_home(struct charlcd *lcd) |
72 | { | |
40c2b72e | 73 | return hd44780_common_gotoxy(lcd, 0, 0); |
88645a86 LP |
74 | } |
75 | EXPORT_SYMBOL_GPL(hd44780_common_home); | |
76 | ||
45421ffe LP |
77 | /* clears the display and resets X/Y */ |
78 | int 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); | |
7b231bb5 LP |
83 | /* datasheet says to wait 1,64 milliseconds */ |
84 | long_sleep(2); | |
45421ffe LP |
85 | return 0; |
86 | } | |
87 | EXPORT_SYMBOL_GPL(hd44780_common_clear_display); | |
88 | ||
01ec46df LP |
89 | int 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 | } | |
162 | EXPORT_SYMBOL_GPL(hd44780_common_init_display); | |
163 | ||
d2f2187e LP |
164 | int 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 | } | |
181 | EXPORT_SYMBOL_GPL(hd44780_common_shift_cursor); | |
182 | ||
183 | int 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 | } | |
196 | EXPORT_SYMBOL_GPL(hd44780_common_shift_display); | |
197 | ||
198 | static 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 | ||
210 | int 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 | } | |
222 | EXPORT_SYMBOL_GPL(hd44780_common_display); | |
223 | ||
224 | int 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 | } | |
236 | EXPORT_SYMBOL_GPL(hd44780_common_cursor); | |
237 | ||
238 | int 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 | } | |
250 | EXPORT_SYMBOL_GPL(hd44780_common_blink); | |
251 | ||
252 | static 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 | ||
263 | int 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 | } | |
275 | EXPORT_SYMBOL_GPL(hd44780_common_fontsize); | |
276 | ||
277 | int 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 | } | |
289 | EXPORT_SYMBOL_GPL(hd44780_common_lines); | |
290 | ||
339acb08 LP |
291 | int 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 */ | |
40c2b72e | 341 | lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y); |
339acb08 LP |
342 | return 1; |
343 | } | |
344 | EXPORT_SYMBOL_GPL(hd44780_common_redefine_char); | |
345 | ||
718e05ed LP |
346 | struct 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 | ||
3fc04dd7 | 354 | hd->ifwidth = 8; |
2545c1c9 LP |
355 | hd->bwidth = DEFAULT_LCD_BWIDTH; |
356 | hd->hwidth = DEFAULT_LCD_HWIDTH; | |
718e05ed LP |
357 | return hd; |
358 | } | |
359 | EXPORT_SYMBOL_GPL(hd44780_common_alloc); | |
360 | ||
361 | MODULE_LICENSE("GPL"); |