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); | |
35b464e3 HV |
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); | |
45421ffe LP |
94 | } |
95 | EXPORT_SYMBOL_GPL(hd44780_common_clear_display); | |
96 | ||
01ec46df LP |
97 | int 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 | } | |
170 | EXPORT_SYMBOL_GPL(hd44780_common_init_display); | |
171 | ||
d2f2187e LP |
172 | int 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 | } | |
189 | EXPORT_SYMBOL_GPL(hd44780_common_shift_cursor); | |
190 | ||
191 | int 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 | } | |
204 | EXPORT_SYMBOL_GPL(hd44780_common_shift_display); | |
205 | ||
206 | static 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 | ||
218 | int 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 | } | |
230 | EXPORT_SYMBOL_GPL(hd44780_common_display); | |
231 | ||
232 | int 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 | } | |
244 | EXPORT_SYMBOL_GPL(hd44780_common_cursor); | |
245 | ||
246 | int 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 | } | |
258 | EXPORT_SYMBOL_GPL(hd44780_common_blink); | |
259 | ||
260 | static 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 | ||
271 | int 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 | } | |
283 | EXPORT_SYMBOL_GPL(hd44780_common_fontsize); | |
284 | ||
285 | int 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 | } | |
297 | EXPORT_SYMBOL_GPL(hd44780_common_lines); | |
298 | ||
339acb08 LP |
299 | int 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 */ | |
40c2b72e | 349 | lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y); |
339acb08 LP |
350 | return 1; |
351 | } | |
352 | EXPORT_SYMBOL_GPL(hd44780_common_redefine_char); | |
353 | ||
718e05ed LP |
354 | struct 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 | ||
3fc04dd7 | 362 | hd->ifwidth = 8; |
2545c1c9 LP |
363 | hd->bwidth = DEFAULT_LCD_BWIDTH; |
364 | hd->hwidth = DEFAULT_LCD_HWIDTH; | |
718e05ed LP |
365 | return hd; |
366 | } | |
367 | EXPORT_SYMBOL_GPL(hd44780_common_alloc); | |
368 | ||
369 | MODULE_LICENSE("GPL"); |