1 /* $NetBSD: hd44780_subr.c,v 1.21 2010/11/13 13:52:01 uebayasi Exp $ */
2 
3 /*
4  * Copyright (c) 2002 Dennis I. Chernoivanov
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 /*
31  * Subroutines for Hitachi HD44870 style displays
32  */
33 
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: hd44780_subr.c,v 1.21 2010/11/13 13:52:01 uebayasi Exp $");
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/conf.h>
40 #include <sys/kernel.h>
41 #include <sys/malloc.h>
42 #include <sys/types.h>
43 #include <sys/ioccom.h>
44 
45 #include <machine/autoconf.h>
46 #include <sys/intr.h>
47 #include <sys/bus.h>
48 
49 #include <dev/wscons/wsdisplayvar.h>
50 #include <dev/wscons/wsconsio.h>
51 #include <dev/wscons/wscons_callbacks.h>
52 
53 #include <dev/ic/hd44780reg.h>
54 #include <dev/ic/hd44780var.h>
55 
56 #define COORD_TO_IDX(x, y)	((y) * sc->sc_cols + (x))
57 #define COORD_TO_DADDR(x, y)	((y) * HD_ROW2_ADDR + (x))
58 #define IDX_TO_ROW(idx)		((idx) / sc->sc_cols)
59 #define IDX_TO_COL(idx)		((idx) % sc->sc_cols)
60 #define IDX_TO_DADDR(idx)	(IDX_TO_ROW((idx)) * HD_ROW2_ADDR + \
61 				IDX_TO_COL((idx)))
62 #define DADDR_TO_ROW(daddr)	((daddr) / HD_ROW2_ADDR)
63 #define DADDR_TO_COL(daddr)	((daddr) % HD_ROW2_ADDR)
64 #define DADDR_TO_CHIPDADDR(daddr)	((daddr) % (HD_ROW2_ADDR * 2))
65 #define DADDR_TO_CHIPNO(daddr)	((daddr) / (HD_ROW2_ADDR * 2))
66 
67 static void	hlcd_cursor(void *, int, int, int);
68 static int	hlcd_mapchar(void *, int, unsigned int *);
69 static void	hlcd_putchar(void *, int, int, u_int, long);
70 static void	hlcd_copycols(void *, int, int, int,int);
71 static void	hlcd_erasecols(void *, int, int, int, long);
72 static void	hlcd_copyrows(void *, int, int, int);
73 static void	hlcd_eraserows(void *, int, int, long);
74 static int	hlcd_allocattr(void *, int, int, int, long *);
75 static void	hlcd_updatechar(struct hd44780_chip *, int, int);
76 static void	hlcd_redraw(void *);
77 
78 const struct wsdisplay_emulops hlcd_emulops = {
79 	hlcd_cursor,
80 	hlcd_mapchar,
81 	hlcd_putchar,
82 	hlcd_copycols,
83 	hlcd_erasecols,
84 	hlcd_copyrows,
85 	hlcd_eraserows,
86 	hlcd_allocattr
87 };
88 
89 static int	hlcd_ioctl(void *, void *, u_long, void *, int, struct lwp *);
90 static paddr_t	hlcd_mmap(void *, void *, off_t, int);
91 static int	hlcd_alloc_screen(void *, const struct wsscreen_descr *,
92 		    void **, int *, int *, long *);
93 static void	hlcd_free_screen(void *, void *);
94 static int	hlcd_show_screen(void *, void *, int,
95 		    void (*) (void *, int, int), void *);
96 
97 const struct wsdisplay_accessops hlcd_accessops = {
98 	hlcd_ioctl,
99 	hlcd_mmap,
100 	hlcd_alloc_screen,
101 	hlcd_free_screen,
102 	hlcd_show_screen,
103 	0 /* load_font */
104 };
105 
106 static void
hlcd_cursor(void * id,int on,int row,int col)107 hlcd_cursor(void *id, int on, int row, int col)
108 {
109 	struct hlcd_screen *hdscr = id;
110 
111 	hdscr->hlcd_curon = on;
112 	hdscr->hlcd_curx = col;
113 	hdscr->hlcd_cury = row;
114 }
115 
116 static int
hlcd_mapchar(void * id,int uni,unsigned int * index)117 hlcd_mapchar(void *id, int uni, unsigned int *index)
118 {
119 
120 	if (uni < 256) {
121 		*index = uni;
122 		return 5;
123 	}
124 	*index = ' ';
125 	return 0;
126 }
127 
128 static void
hlcd_putchar(void * id,int row,int col,u_int c,long attr)129 hlcd_putchar(void *id, int row, int col, u_int c, long attr)
130 {
131 	struct hlcd_screen *hdscr = id;
132 
133 	c &= 0xff;
134 	if (row > 0 && (hdscr->hlcd_sc->sc_flags & (HD_MULTILINE|HD_MULTICHIP)))
135 		hdscr->image[hdscr->hlcd_sc->sc_cols * row + col] = c;
136 	else
137 		hdscr->image[col] = c;
138 }
139 
140 /*
141  * copies columns inside a row.
142  */
143 static void
hlcd_copycols(void * id,int row,int srccol,int dstcol,int ncols)144 hlcd_copycols(void *id, int row, int srccol, int dstcol, int ncols)
145 {
146 	struct hlcd_screen *hdscr = id;
147 
148 	if ((dstcol + ncols - 1) > hdscr->hlcd_sc->sc_cols)
149 		ncols = hdscr->hlcd_sc->sc_cols - srccol;
150 
151 	if (row > 0 && (hdscr->hlcd_sc->sc_flags & (HD_MULTILINE|HD_MULTICHIP)))
152 		memmove(&hdscr->image[hdscr->hlcd_sc->sc_cols * row + dstcol],
153 		    &hdscr->image[hdscr->hlcd_sc->sc_cols * row + srccol],
154 		    ncols);
155 	else
156 		memmove(&hdscr->image[dstcol], &hdscr->image[srccol], ncols);
157 }
158 
159 
160 /*
161  * Erases a bunch of chars inside one row.
162  */
163 static void
hlcd_erasecols(void * id,int row,int startcol,int ncols,long fillattr)164 hlcd_erasecols(void *id, int row, int startcol, int ncols, long fillattr)
165 {
166 	struct hlcd_screen *hdscr = id;
167 
168 	if ((startcol + ncols) > hdscr->hlcd_sc->sc_cols)
169 		ncols = hdscr->hlcd_sc->sc_cols - startcol;
170 
171 	if (row > 0 && (hdscr->hlcd_sc->sc_flags & (HD_MULTILINE|HD_MULTICHIP)))
172 		memset(&hdscr->image[hdscr->hlcd_sc->sc_cols * row + startcol],
173 		    ' ', ncols);
174 	else
175 		memset(&hdscr->image[startcol], ' ', ncols);
176 }
177 
178 
179 static void
hlcd_copyrows(void * id,int srcrow,int dstrow,int nrows)180 hlcd_copyrows(void *id, int srcrow, int dstrow, int nrows)
181 {
182 	struct hlcd_screen *hdscr = id;
183 	int ncols = hdscr->hlcd_sc->sc_cols;
184 
185 	if (!(hdscr->hlcd_sc->sc_flags & (HD_MULTILINE|HD_MULTICHIP)))
186 		return;
187 	memmove(&hdscr->image[dstrow * ncols], &hdscr->image[srcrow * ncols],
188 	    nrows * ncols);
189 }
190 
191 static void
hlcd_eraserows(void * id,int startrow,int nrows,long fillattr)192 hlcd_eraserows(void *id, int startrow, int nrows, long fillattr)
193 {
194 	struct hlcd_screen *hdscr = id;
195 	int ncols = hdscr->hlcd_sc->sc_cols;
196 
197 	memset(&hdscr->image[startrow * ncols], ' ', ncols * nrows);
198 }
199 
200 
201 static int
hlcd_allocattr(void * id,int fg,int bg,int flags,long * attrp)202 hlcd_allocattr(void *id, int fg, int bg, int flags, long *attrp)
203 {
204 
205         *attrp = flags;
206         return 0;
207 }
208 
209 static int
hlcd_ioctl(void * v,void * vs,u_long cmd,void * data,int flag,struct lwp * l)210 hlcd_ioctl(void *v, void *vs, u_long cmd, void *data, int flag, struct lwp *l)
211 {
212 
213 	switch (cmd) {
214 	case WSDISPLAYIO_GTYPE:
215 		*(u_int *)data = WSDISPLAY_TYPE_HDLCD;
216 		break;
217 
218 	case WSDISPLAYIO_SVIDEO:
219 		break;
220 
221 	case WSDISPLAYIO_GVIDEO:
222 		*(u_int *)data = WSDISPLAYIO_VIDEO_ON;
223 		break;
224 
225 	default:
226 		return EPASSTHROUGH;
227 	}
228 	return 0;
229 }
230 
231 static paddr_t
hlcd_mmap(void * v,void * vs,off_t offset,int prot)232 hlcd_mmap(void *v, void *vs, off_t offset, int prot)
233 {
234 
235 	return -1;
236 }
237 
238 static int
hlcd_alloc_screen(void * v,const struct wsscreen_descr * type,void ** cookiep,int * curxp,int * curyp,long * defattrp)239 hlcd_alloc_screen(void *v, const struct wsscreen_descr *type, void **cookiep,
240     int *curxp, int *curyp, long *defattrp)
241 {
242 	struct hlcd_screen *hdscr = v, *new;
243 
244 	new = *cookiep = malloc(sizeof(struct hlcd_screen),
245 				M_DEVBUF, M_WAITOK|M_ZERO);
246 	new->hlcd_sc = hdscr->hlcd_sc;
247 	new->image = malloc(PAGE_SIZE, M_DEVBUF, M_WAITOK);
248 	memset(new->image, ' ', PAGE_SIZE);
249 	*curxp = *curyp = *defattrp = 0;
250 	return 0;
251 }
252 
253 static void
hlcd_free_screen(void * v,void * cookie)254 hlcd_free_screen(void *v, void *cookie)
255 {
256 }
257 
258 static int
hlcd_show_screen(void * v,void * cookie,int waitok,void (* cb)(void *,int,int),void * cbarg)259 hlcd_show_screen(void *v, void *cookie, int waitok,
260     void (*cb)(void *, int, int), void *cbarg)
261 {
262 	struct hlcd_screen *hdscr = v;
263 
264 	hdscr->hlcd_sc->sc_curscr = cookie;
265 	callout_schedule(&hdscr->hlcd_sc->redraw, 1);
266 	return 0;
267 }
268 
269 static void
hlcd_updatechar(struct hd44780_chip * sc,int daddr,int c)270 hlcd_updatechar(struct hd44780_chip *sc, int daddr, int c)
271 {
272 	int curdaddr, en, chipdaddr;
273 
274 	curdaddr = COORD_TO_DADDR(sc->sc_screen.hlcd_curx,
275 	    sc->sc_screen.hlcd_cury);
276 	en = DADDR_TO_CHIPNO(daddr);
277 	chipdaddr = DADDR_TO_CHIPDADDR(daddr);
278 	if (daddr != curdaddr)
279 		hd44780_ir_write(sc, en, cmd_ddramset(chipdaddr));
280 
281 	hd44780_dr_write(sc, en, c);
282 
283 	daddr++;
284 	sc->sc_screen.hlcd_curx = DADDR_TO_COL(daddr);
285 	sc->sc_screen.hlcd_cury = DADDR_TO_ROW(daddr);
286 }
287 
288 static void
hlcd_redraw(void * arg)289 hlcd_redraw(void *arg)
290 {
291 	struct hd44780_chip *sc = arg;
292 	int len, crsridx, startidx, x, y;
293 	int old_en, new_en;
294 	uint8_t *img, *curimg;
295 
296 	if (sc->sc_curscr == NULL)
297 		return;
298 
299 	if (sc->sc_flags & HD_MULTILINE)
300 		len = 2 * sc->sc_cols;
301 	else
302 		len = sc->sc_cols;
303 
304 	if (sc->sc_flags & HD_MULTICHIP)
305 		len = len * 2;
306 
307 	x = sc->sc_screen.hlcd_curx;
308 	y = sc->sc_screen.hlcd_cury;
309 	old_en = DADDR_TO_CHIPNO(COORD_TO_DADDR(x, y));
310 
311 	img = sc->sc_screen.image;
312 	curimg = sc->sc_curscr->image;
313 	startidx = crsridx =
314 	    COORD_TO_IDX(sc->sc_screen.hlcd_curx, sc->sc_screen.hlcd_cury);
315 	do {
316 		if (img[crsridx] != curimg[crsridx]) {
317 			hlcd_updatechar(sc, IDX_TO_DADDR(crsridx),
318 			    curimg[crsridx]);
319 			img[crsridx] = curimg[crsridx];
320 		}
321 		crsridx++;
322 		if (crsridx == len)
323 			crsridx = 0;
324 	} while (crsridx != startidx);
325 
326 	x = sc->sc_curscr->hlcd_curx;
327 	y = sc->sc_curscr->hlcd_cury;
328 	new_en = DADDR_TO_CHIPNO(COORD_TO_DADDR(x, y));
329 
330 	if (sc->sc_screen.hlcd_curx != sc->sc_curscr->hlcd_curx ||
331 	    sc->sc_screen.hlcd_cury != sc->sc_curscr->hlcd_cury) {
332 
333 		x = sc->sc_screen.hlcd_curx = sc->sc_curscr->hlcd_curx;
334 		y = sc->sc_screen.hlcd_cury = sc->sc_curscr->hlcd_cury;
335 
336 		hd44780_ir_write(sc, new_en, cmd_ddramset(
337 		    DADDR_TO_CHIPDADDR(COORD_TO_DADDR(x, y))));
338 
339 	}
340 
341 	/* visible cursor switched to other chip */
342 	if (old_en != new_en && sc->sc_screen.hlcd_curon) {
343 		hd44780_ir_write(sc, old_en, cmd_dispctl(1, 0, 0));
344 		hd44780_ir_write(sc, new_en, cmd_dispctl(1, 1, 1));
345 	}
346 
347 	if (sc->sc_screen.hlcd_curon != sc->sc_curscr->hlcd_curon) {
348 		sc->sc_screen.hlcd_curon = sc->sc_curscr->hlcd_curon;
349 		if (sc->sc_screen.hlcd_curon)
350 			hd44780_ir_write(sc, new_en, cmd_dispctl(1, 1, 1));
351 		else
352 			hd44780_ir_write(sc, new_en, cmd_dispctl(1, 0, 0));
353 	}
354 
355 	callout_schedule(&sc->redraw, 1);
356 }
357 
358 
359 /*
360  * Finish device attach. sc_writereg, sc_readreg and sc_flags must be properly
361  * initialized prior to this call.
362  */
363 void
hd44780_attach_subr(struct hd44780_chip * sc)364 hd44780_attach_subr(struct hd44780_chip *sc)
365 {
366 	int err = 0;
367 
368 	/* Putc/getc are supposed to be set by platform-dependent code. */
369 	if ((sc->sc_writereg == NULL) || (sc->sc_readreg == NULL))
370 		sc->sc_dev_ok = 0;
371 
372 	/* Make sure that HD_MAX_CHARS is enough. */
373 	if ((sc->sc_flags & HD_MULTILINE) && (2 * sc->sc_cols > HD_MAX_CHARS))
374 		sc->sc_dev_ok = 0;
375 	else if (sc->sc_cols > HD_MAX_CHARS)
376 		sc->sc_dev_ok = 0;
377 
378 	if (sc->sc_dev_ok) {
379 		if ((sc->sc_flags & HD_UP) == 0)
380 			err = hd44780_init(sc);
381 		if (err != 0)
382 			aprint_error_dev(sc->sc_dev,
383 			    "LCD not responding or unconnected\n");
384 	}
385 
386 	sc->sc_screen.hlcd_sc = sc;
387 
388 	sc->sc_screen.image = malloc(PAGE_SIZE, M_DEVBUF, M_WAITOK);
389 	memset(sc->sc_screen.image, ' ', PAGE_SIZE);
390 	sc->sc_curscr = NULL;
391 	sc->sc_curchip = 0;
392 	callout_init(&sc->redraw, 0);
393 	callout_setfunc(&sc->redraw, hlcd_redraw, sc);
394 }
395 
hd44780_init(struct hd44780_chip * sc)396 int hd44780_init(struct hd44780_chip *sc)
397 {
398 	int ret;
399 
400 	ret = hd44780_chipinit(sc, 0);
401 	if (ret != 0 || !(sc->sc_flags & HD_MULTICHIP))
402 		return ret;
403 	else
404 		return hd44780_chipinit(sc, 1);
405 }
406 
407 /*
408  * Initialize 4-bit or 8-bit connected device.
409  */
410 int
hd44780_chipinit(struct hd44780_chip * sc,uint32_t en)411 hd44780_chipinit(struct hd44780_chip *sc, uint32_t en)
412 {
413 	uint8_t cmd, dat;
414 
415 	sc->sc_flags &= ~(HD_TIMEDOUT|HD_UP);
416 	sc->sc_dev_ok = 1;
417 
418 	cmd = cmd_init(sc->sc_flags & HD_8BIT);
419 	hd44780_ir_write(sc, en, cmd);
420 	delay(HD_TIMEOUT_LONG);
421 	hd44780_ir_write(sc, en, cmd);
422 	hd44780_ir_write(sc, en, cmd);
423 
424 	cmd = cmd_funcset(
425 			sc->sc_flags & HD_8BIT,
426 			sc->sc_flags & HD_MULTILINE,
427 			sc->sc_flags & HD_BIGFONT);
428 
429 	if ((sc->sc_flags & HD_8BIT) == 0)
430 		hd44780_ir_write(sc, en, cmd);
431 
432 	sc->sc_flags |= HD_UP;
433 
434 	hd44780_ir_write(sc, en, cmd);
435 	hd44780_ir_write(sc, en, cmd_dispctl(0, 0, 0));
436 	hd44780_ir_write(sc, en, cmd_clear());
437 	hd44780_ir_write(sc, en, cmd_modset(1, 0));
438 
439 	if (sc->sc_flags & HD_TIMEDOUT) {
440 		sc->sc_flags &= ~HD_UP;
441 		return EIO;
442 	}
443 
444 	/* Turn display on and clear it. */
445 	hd44780_ir_write(sc, en, cmd_clear());
446 	hd44780_ir_write(sc, en, cmd_dispctl(1, 0, 0));
447 
448 	/* Attempt a simple probe for presence */
449 	hd44780_ir_write(sc, en, cmd_ddramset(0x5));
450 	hd44780_ir_write(sc, en, cmd_shift(0, 1));
451 	hd44780_busy_wait(sc, en);
452 	if ((dat = hd44780_ir_read(sc, en) & 0x7f) != 0x6) {
453 		sc->sc_dev_ok = 0;
454 		sc->sc_flags &= ~HD_UP;
455 		return EIO;
456 	}
457 	hd44780_ir_write(sc, en, cmd_ddramset(0));
458 
459 	return 0;
460 }
461 
462 /*
463  * Standard hd44780 ioctl() functions.
464  */
465 int
hd44780_ioctl_subr(struct hd44780_chip * sc,u_long cmd,void * data)466 hd44780_ioctl_subr(struct hd44780_chip *sc, u_long cmd, void *data)
467 {
468 	uint8_t tmp;
469 	int error = 0;
470 	uint32_t en = sc->sc_curchip;
471 
472 #define hd44780_io()	((struct hd44780_io *)data)
473 #define hd44780_info()	((struct hd44780_info *)data)
474 #define hd44780_ctrl()	((struct hd44780_dispctl *)data)
475 
476 	switch (cmd) {
477 	case HLCD_CLEAR:
478 		/* Clear the LCD. */
479 		hd44780_ir_write(sc, en, cmd_clear());
480 		break;
481 
482 	case HLCD_CURSOR_LEFT:
483 		/* Move the cursor one position to the left. */
484 		hd44780_ir_write(sc, en, cmd_shift(0, 0));
485 			break;
486 
487 	case HLCD_CURSOR_RIGHT:
488 		/* Move the cursor one position to the right. */
489 		hd44780_ir_write(sc, en, cmd_shift(0, 1));
490 		break;
491 
492 	case HLCD_DISPCTL:
493 		/* Control the LCD. */
494 		hd44780_ir_write(sc, en, cmd_dispctl(
495 					hd44780_ctrl()->display_on,
496 					hd44780_ctrl()->cursor_on,
497 					hd44780_ctrl()->blink_on));
498 		break;
499 
500 	case HLCD_GET_INFO:
501 		/* Get LCD configuration. */
502 		hd44780_info()->lines
503 			= (sc->sc_flags & HD_MULTILINE) ? 2 : 1;
504 		if (sc->sc_flags & HD_MULTICHIP)
505 			hd44780_info()->lines *= 2;
506 		hd44780_info()->phys_rows = sc->sc_cols;
507 		hd44780_info()->virt_rows = sc->sc_vcols;
508 		hd44780_info()->is_wide = sc->sc_flags & HD_8BIT;
509 		hd44780_info()->is_bigfont = sc->sc_flags & HD_BIGFONT;
510 		hd44780_info()->kp_present = sc->sc_flags & HD_KEYPAD;
511 		break;
512 
513 
514 	case HLCD_RESET:
515 		/* Reset the LCD. */
516 		error = hd44780_init(sc);
517 		break;
518 
519 	case HLCD_GET_CURSOR_POS:
520 		/* Get the current cursor position. */
521 		hd44780_io()->dat = (hd44780_ir_read(sc, en) & 0x7f);
522 		break;
523 
524 	case HLCD_SET_CURSOR_POS:
525 		/* Set the cursor position. */
526 		hd44780_ir_write(sc, en, cmd_ddramset(hd44780_io()->dat));
527 		break;
528 
529 	case HLCD_GETC:
530 		/* Get the value at the current cursor position. */
531 		tmp = (hd44780_ir_read(sc, en) & 0x7f);
532 		hd44780_ir_write(sc, en, cmd_ddramset(tmp));
533 		hd44780_io()->dat = hd44780_dr_read(sc, en);
534 		break;
535 
536 	case HLCD_PUTC:
537 		/* Set the character at the cursor position + advance cursor. */
538 		hd44780_dr_write(sc, en, hd44780_io()->dat);
539 		break;
540 
541 	case HLCD_SHIFT_LEFT:
542 		/* Shift display left. */
543 		hd44780_ir_write(sc, en, cmd_shift(1, 0));
544 		break;
545 
546 	case HLCD_SHIFT_RIGHT:
547 		/* Shift display right. */
548 		hd44780_ir_write(sc, en, cmd_shift(1, 1));
549 		break;
550 
551 	case HLCD_HOME:
552 		/* Return home. */
553 		hd44780_ir_write(sc, en, cmd_rethome());
554 		break;
555 
556 	case HLCD_WRITE:
557 		/* Write a string to the LCD virtual area. */
558 		error = hd44780_ddram_io(sc, en, hd44780_io(), HD_DDRAM_WRITE);
559 		break;
560 
561 	case HLCD_READ:
562 		/* Read LCD virtual area. */
563 		error = hd44780_ddram_io(sc, en, hd44780_io(), HD_DDRAM_READ);
564 		break;
565 
566 	case HLCD_REDRAW:
567 		/* Write to the LCD visible area. */
568 		hd44780_ddram_redraw(sc, en, hd44780_io());
569 		break;
570 
571 	case HLCD_WRITE_INST:
572 		/* Write raw instruction. */
573 		hd44780_ir_write(sc, en, hd44780_io()->dat);
574 		break;
575 
576 	case HLCD_WRITE_DATA:
577 		/* Write raw data. */
578 		hd44780_dr_write(sc, en, hd44780_io()->dat);
579 		break;
580 
581 	case HLCD_GET_CHIPNO:
582 		/* Get current chip 0 or 1 (top or bottom) */
583 		*(uint8_t *)data = sc->sc_curchip;
584 		break;
585 
586 	case HLCD_SET_CHIPNO:
587 		/* Set current chip 0 or 1 (top or bottom) */
588 		sc->sc_curchip = *(uint8_t *)data;
589 		break;
590 
591 	default:
592 		error = EINVAL;
593 	}
594 
595 	if (sc->sc_flags & HD_TIMEDOUT)
596 		error = EIO;
597 
598 	return error;
599 }
600 
601 /*
602  * Read/write particular area of the LCD screen.
603  */
604 int
hd44780_ddram_io(struct hd44780_chip * sc,uint32_t en,struct hd44780_io * io,uint8_t dir)605 hd44780_ddram_io(struct hd44780_chip *sc, uint32_t en, struct hd44780_io *io,
606     uint8_t dir)
607 {
608 	uint8_t hi;
609 	uint8_t addr;
610 	int error = 0;
611 	uint8_t i = 0;
612 
613 	if (io->dat < sc->sc_vcols) {
614 		hi = HD_ROW1_ADDR + sc->sc_vcols;
615 		addr = HD_ROW1_ADDR + io->dat;
616 		for (; (addr < hi) && (i < io->len); addr++, i++) {
617 			hd44780_ir_write(sc, en, cmd_ddramset(addr));
618 			if (dir == HD_DDRAM_READ)
619 				io->buf[i] = hd44780_dr_read(sc, en);
620 			else
621 				hd44780_dr_write(sc, en, io->buf[i]);
622 		}
623 	}
624 	if (io->dat < 2 * sc->sc_vcols) {
625 		hi = HD_ROW2_ADDR + sc->sc_vcols;
626 		if (io->dat >= sc->sc_vcols)
627 			addr = HD_ROW2_ADDR + io->dat - sc->sc_vcols;
628 		else
629 			addr = HD_ROW2_ADDR;
630 		for (; (addr < hi) && (i < io->len); addr++, i++) {
631 			hd44780_ir_write(sc, en, cmd_ddramset(addr));
632 			if (dir == HD_DDRAM_READ)
633 				io->buf[i] = hd44780_dr_read(sc, en);
634 			else
635 				hd44780_dr_write(sc, en, io->buf[i]);
636 		}
637 		if (i < io->len)
638 			io->len = i;
639 	} else {
640 		error = EINVAL;
641 	}
642 	return error;
643 }
644 
645 /*
646  * Write to the visible area of the display.
647  */
648 void
hd44780_ddram_redraw(struct hd44780_chip * sc,uint32_t en,struct hd44780_io * io)649 hd44780_ddram_redraw(struct hd44780_chip *sc, uint32_t en,
650     struct hd44780_io *io)
651 {
652 	uint8_t i;
653 
654 	hd44780_ir_write(sc, en, cmd_clear());
655 	hd44780_ir_write(sc, en, cmd_rethome());
656 	hd44780_ir_write(sc, en, cmd_ddramset(HD_ROW1_ADDR));
657 	for (i = 0; (i < io->len) && (i < sc->sc_cols); i++) {
658 		hd44780_dr_write(sc, en, io->buf[i]);
659 	}
660 	hd44780_ir_write(sc, en, cmd_ddramset(HD_ROW2_ADDR));
661 	for (; (i < io->len); i++)
662 		hd44780_dr_write(sc, en, io->buf[i]);
663 }
664 
665 void
hd44780_busy_wait(struct hd44780_chip * sc,uint32_t en)666 hd44780_busy_wait(struct hd44780_chip *sc, uint32_t en)
667 {
668 	int nloops = 100;
669 
670 	if (sc->sc_flags & HD_TIMEDOUT)
671 		return;
672 
673 	while (nloops-- && (hd44780_ir_read(sc, en) & BUSY_FLAG) == BUSY_FLAG)
674 		continue;
675 
676 	if (nloops == 0) {
677 		sc->sc_flags |= HD_TIMEDOUT;
678 		sc->sc_dev_ok = 0;
679 	}
680 }
681 
682 #if defined(HD44780_STD_WIDE)
683 /*
684  * Standard 8-bit version of 'sc_writereg' (8-bit port, 8-bit access)
685  */
686 void
hd44780_writereg(struct hd44780_chip * sc,uint32_t en,uint32_t reg,uint8_t cmd)687 hd44780_writereg(struct hd44780_chip *sc, uint32_t en, uint32_t reg,
688     uint8_t cmd)
689 {
690 	bus_space_tag_t iot = sc->sc_iot;
691 	bus_space_handle_t ioh;
692 
693 	if (sc->sc_dev_ok == 0)
694 		return;
695 
696 	if (reg == 0)
697 		ioh = sc->sc_ioir;
698 	else
699 		ioh = sc->sc_iodr;
700 
701 	bus_space_write_1(iot, ioh, 0x00, cmd);
702 	delay(HD_TIMEOUT_NORMAL);
703 }
704 
705 /*
706  * Standard 8-bit version of 'sc_readreg' (8-bit port, 8-bit access)
707  */
708 uint8_t
hd44780_readreg(struct hd44780_chip * sc,uint32_t en,uint32_t reg)709 hd44780_readreg(struct hd44780_chip *sc, uint32_t en, uint32_t reg)
710 {
711 	bus_space_tag_t iot = sc->sc_iot;
712 	bus_space_handle_t ioh;
713 
714 	if (sc->sc_dev_ok == 0)
715 		return;
716 
717 	if (reg == 0)
718 		ioh = sc->sc_ioir;
719 	else
720 		ioh = sc->sc_iodr;
721 
722 	delay(HD_TIMEOUT_NORMAL);
723 	return bus_space_read_1(iot, ioh, 0x00);
724 }
725 #elif defined(HD44780_STD_SHORT)
726 /*
727  * Standard 4-bit version of 'sc_writereg' (4-bit port, 8-bit access)
728  */
729 void
hd44780_writereg(struct hd44780_chip * sc,uint32_t en,uint32_t reg,uint8_t cmd)730 hd44780_writereg(struct hd44780_chip *sc, uint32_t en, uint32_t reg,
731     uint8_t cmd)
732 {
733 	bus_space_tag_t iot = sc->sc_iot;
734 	bus_space_handle_t ioh;
735 
736 	if (sc->sc_dev_ok == 0)
737 		return;
738 
739 	if (reg == 0)
740 		ioh = sc->sc_ioir;
741 	else
742 		ioh = sc->sc_iodr;
743 
744 	bus_space_write_1(iot, ioh, 0x00, hi_bits(cmd));
745 	if (sc->sc_flags & HD_UP)
746 		bus_space_write_1(iot, ioh, 0x00, lo_bits(cmd));
747 	delay(HD_TIMEOUT_NORMAL);
748 }
749 
750 /*
751  * Standard 4-bit version of 'sc_readreg' (4-bit port, 8-bit access)
752  */
753 uint8_t
hd44780_readreg(struct hd44780_chip * sc,uint32_t en,uint32_t reg)754 hd44780_readreg(struct hd44780_chip *sc, uint32_t en, uint32_t reg)
755 {
756 	bus_space_tag_t iot = sc->sc_iot;
757 	bus_space_handle_t ioh;
758 	uint8_t rd, dat;
759 
760 	if (sc->sc_dev_ok == 0)
761 		return;
762 
763 	if (reg == 0)
764 		ioh = sc->sc_ioir;
765 	else
766 		ioh = sc->sc_iodr;
767 
768 	rd = bus_space_read_1(iot, ioh, 0x00);
769 	dat = (rd & 0x0f) << 4;
770 	rd = bus_space_read_1(iot, ioh, 0x00);
771 	return (dat | (rd & 0x0f));
772 }
773 #endif
774