]> git.karo-electronics.de Git - mv-sheeva.git/blob - drivers/video/fbmon.c
ACPI / PM: Introduce function for refcounting device power resources
[mv-sheeva.git] / drivers / video / fbmon.c
1 /*
2  * linux/drivers/video/fbmon.c
3  *
4  * Copyright (C) 2002 James Simmons <jsimmons@users.sf.net>
5  *
6  * Credits:
7  *
8  * The EDID Parser is a conglomeration from the following sources:
9  *
10  *   1. SciTech SNAP Graphics Architecture
11  *      Copyright (C) 1991-2002 SciTech Software, Inc. All rights reserved.
12  *
13  *   2. XFree86 4.3.0, interpret_edid.c
14  *      Copyright 1998 by Egbert Eich <Egbert.Eich@Physik.TU-Darmstadt.DE>
15  *
16  *   3. John Fremlin <vii@users.sourceforge.net> and
17  *      Ani Joshi <ajoshi@unixbox.com>
18  *
19  * Generalized Timing Formula is derived from:
20  *
21  *      GTF Spreadsheet by Andy Morrish (1/5/97)
22  *      available at http://www.vesa.org
23  *
24  * This file is subject to the terms and conditions of the GNU General Public
25  * License.  See the file COPYING in the main directory of this archive
26  * for more details.
27  *
28  */
29 #include <linux/fb.h>
30 #include <linux/module.h>
31 #include <linux/pci.h>
32 #include <linux/slab.h>
33 #include <video/edid.h>
34 #ifdef CONFIG_PPC_OF
35 #include <asm/prom.h>
36 #include <asm/pci-bridge.h>
37 #endif
38 #include "edid.h"
39
40 /*
41  * EDID parser
42  */
43
44 #undef DEBUG  /* define this for verbose EDID parsing output */
45
46 #ifdef DEBUG
47 #define DPRINTK(fmt, args...) printk(fmt,## args)
48 #else
49 #define DPRINTK(fmt, args...)
50 #endif
51
52 #define FBMON_FIX_HEADER  1
53 #define FBMON_FIX_INPUT   2
54 #define FBMON_FIX_TIMINGS 3
55
56 #ifdef CONFIG_FB_MODE_HELPERS
57 struct broken_edid {
58         u8  manufacturer[4];
59         u32 model;
60         u32 fix;
61 };
62
63 static const struct broken_edid brokendb[] = {
64         /* DEC FR-PCXAV-YZ */
65         {
66                 .manufacturer = "DEC",
67                 .model        = 0x073a,
68                 .fix          = FBMON_FIX_HEADER,
69         },
70         /* ViewSonic PF775a */
71         {
72                 .manufacturer = "VSC",
73                 .model        = 0x5a44,
74                 .fix          = FBMON_FIX_INPUT,
75         },
76         /* Sharp UXGA? */
77         {
78                 .manufacturer = "SHP",
79                 .model        = 0x138e,
80                 .fix          = FBMON_FIX_TIMINGS,
81         },
82 };
83
84 static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
85         0xff, 0xff, 0xff, 0x00
86 };
87
88 static void copy_string(unsigned char *c, unsigned char *s)
89 {
90   int i;
91   c = c + 5;
92   for (i = 0; (i < 13 && *c != 0x0A); i++)
93     *(s++) = *(c++);
94   *s = 0;
95   while (i-- && (*--s == 0x20)) *s = 0;
96 }
97
98 static int edid_is_serial_block(unsigned char *block)
99 {
100         if ((block[0] == 0x00) && (block[1] == 0x00) &&
101             (block[2] == 0x00) && (block[3] == 0xff) &&
102             (block[4] == 0x00))
103                 return 1;
104         else
105                 return 0;
106 }
107
108 static int edid_is_ascii_block(unsigned char *block)
109 {
110         if ((block[0] == 0x00) && (block[1] == 0x00) &&
111             (block[2] == 0x00) && (block[3] == 0xfe) &&
112             (block[4] == 0x00))
113                 return 1;
114         else
115                 return 0;
116 }
117
118 static int edid_is_limits_block(unsigned char *block)
119 {
120         if ((block[0] == 0x00) && (block[1] == 0x00) &&
121             (block[2] == 0x00) && (block[3] == 0xfd) &&
122             (block[4] == 0x00))
123                 return 1;
124         else
125                 return 0;
126 }
127
128 static int edid_is_monitor_block(unsigned char *block)
129 {
130         if ((block[0] == 0x00) && (block[1] == 0x00) &&
131             (block[2] == 0x00) && (block[3] == 0xfc) &&
132             (block[4] == 0x00))
133                 return 1;
134         else
135                 return 0;
136 }
137
138 static int edid_is_timing_block(unsigned char *block)
139 {
140         if ((block[0] != 0x00) || (block[1] != 0x00) ||
141             (block[2] != 0x00) || (block[4] != 0x00))
142                 return 1;
143         else
144                 return 0;
145 }
146
147 static int check_edid(unsigned char *edid)
148 {
149         unsigned char *block = edid + ID_MANUFACTURER_NAME, manufacturer[4];
150         unsigned char *b;
151         u32 model;
152         int i, fix = 0, ret = 0;
153
154         manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
155         manufacturer[1] = ((block[0] & 0x03) << 3) +
156                 ((block[1] & 0xe0) >> 5) + '@';
157         manufacturer[2] = (block[1] & 0x1f) + '@';
158         manufacturer[3] = 0;
159         model = block[2] + (block[3] << 8);
160
161         for (i = 0; i < ARRAY_SIZE(brokendb); i++) {
162                 if (!strncmp(manufacturer, brokendb[i].manufacturer, 4) &&
163                         brokendb[i].model == model) {
164                         fix = brokendb[i].fix;
165                         break;
166                 }
167         }
168
169         switch (fix) {
170         case FBMON_FIX_HEADER:
171                 for (i = 0; i < 8; i++) {
172                         if (edid[i] != edid_v1_header[i]) {
173                                 ret = fix;
174                                 break;
175                         }
176                 }
177                 break;
178         case FBMON_FIX_INPUT:
179                 b = edid + EDID_STRUCT_DISPLAY;
180                 /* Only if display is GTF capable will
181                    the input type be reset to analog */
182                 if (b[4] & 0x01 && b[0] & 0x80)
183                         ret = fix;
184                 break;
185         case FBMON_FIX_TIMINGS:
186                 b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
187                 ret = fix;
188
189                 for (i = 0; i < 4; i++) {
190                         if (edid_is_limits_block(b)) {
191                                 ret = 0;
192                                 break;
193                         }
194
195                         b += DETAILED_TIMING_DESCRIPTION_SIZE;
196                 }
197
198                 break;
199         }
200
201         if (ret)
202                 printk("fbmon: The EDID Block of "
203                        "Manufacturer: %s Model: 0x%x is known to "
204                        "be broken,\n",  manufacturer, model);
205
206         return ret;
207 }
208
209 static void fix_edid(unsigned char *edid, int fix)
210 {
211         int i;
212         unsigned char *b, csum = 0;
213
214         switch (fix) {
215         case FBMON_FIX_HEADER:
216                 printk("fbmon: trying a header reconstruct\n");
217                 memcpy(edid, edid_v1_header, 8);
218                 break;
219         case FBMON_FIX_INPUT:
220                 printk("fbmon: trying to fix input type\n");
221                 b = edid + EDID_STRUCT_DISPLAY;
222                 b[0] &= ~0x80;
223                 edid[127] += 0x80;
224                 break;
225         case FBMON_FIX_TIMINGS:
226                 printk("fbmon: trying to fix monitor timings\n");
227                 b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
228                 for (i = 0; i < 4; i++) {
229                         if (!(edid_is_serial_block(b) ||
230                               edid_is_ascii_block(b) ||
231                               edid_is_monitor_block(b) ||
232                               edid_is_timing_block(b))) {
233                                 b[0] = 0x00;
234                                 b[1] = 0x00;
235                                 b[2] = 0x00;
236                                 b[3] = 0xfd;
237                                 b[4] = 0x00;
238                                 b[5] = 60;   /* vfmin */
239                                 b[6] = 60;   /* vfmax */
240                                 b[7] = 30;   /* hfmin */
241                                 b[8] = 75;   /* hfmax */
242                                 b[9] = 17;   /* pixclock - 170 MHz*/
243                                 b[10] = 0;   /* GTF */
244                                 break;
245                         }
246
247                         b += DETAILED_TIMING_DESCRIPTION_SIZE;
248                 }
249
250                 for (i = 0; i < EDID_LENGTH - 1; i++)
251                         csum += edid[i];
252
253                 edid[127] = 256 - csum;
254                 break;
255         }
256 }
257
258 static int edid_checksum(unsigned char *edid)
259 {
260         unsigned char csum = 0, all_null = 0;
261         int i, err = 0, fix = check_edid(edid);
262
263         if (fix)
264                 fix_edid(edid, fix);
265
266         for (i = 0; i < EDID_LENGTH; i++) {
267                 csum += edid[i];
268                 all_null |= edid[i];
269         }
270
271         if (csum == 0x00 && all_null) {
272                 /* checksum passed, everything's good */
273                 err = 1;
274         }
275
276         return err;
277 }
278
279 static int edid_check_header(unsigned char *edid)
280 {
281         int i, err = 1, fix = check_edid(edid);
282
283         if (fix)
284                 fix_edid(edid, fix);
285
286         for (i = 0; i < 8; i++) {
287                 if (edid[i] != edid_v1_header[i])
288                         err = 0;
289         }
290
291         return err;
292 }
293
294 static void parse_vendor_block(unsigned char *block, struct fb_monspecs *specs)
295 {
296         specs->manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
297         specs->manufacturer[1] = ((block[0] & 0x03) << 3) +
298                 ((block[1] & 0xe0) >> 5) + '@';
299         specs->manufacturer[2] = (block[1] & 0x1f) + '@';
300         specs->manufacturer[3] = 0;
301         specs->model = block[2] + (block[3] << 8);
302         specs->serial = block[4] + (block[5] << 8) +
303                (block[6] << 16) + (block[7] << 24);
304         specs->year = block[9] + 1990;
305         specs->week = block[8];
306         DPRINTK("   Manufacturer: %s\n", specs->manufacturer);
307         DPRINTK("   Model: %x\n", specs->model);
308         DPRINTK("   Serial#: %u\n", specs->serial);
309         DPRINTK("   Year: %u Week %u\n", specs->year, specs->week);
310 }
311
312 static void get_dpms_capabilities(unsigned char flags,
313                                   struct fb_monspecs *specs)
314 {
315         specs->dpms = 0;
316         if (flags & DPMS_ACTIVE_OFF)
317                 specs->dpms |= FB_DPMS_ACTIVE_OFF;
318         if (flags & DPMS_SUSPEND)
319                 specs->dpms |= FB_DPMS_SUSPEND;
320         if (flags & DPMS_STANDBY)
321                 specs->dpms |= FB_DPMS_STANDBY;
322         DPRINTK("      DPMS: Active %s, Suspend %s, Standby %s\n",
323                (flags & DPMS_ACTIVE_OFF) ? "yes" : "no",
324                (flags & DPMS_SUSPEND)    ? "yes" : "no",
325                (flags & DPMS_STANDBY)    ? "yes" : "no");
326 }
327
328 static void get_chroma(unsigned char *block, struct fb_monspecs *specs)
329 {
330         int tmp;
331
332         DPRINTK("      Chroma\n");
333         /* Chromaticity data */
334         tmp = ((block[5] & (3 << 6)) >> 6) | (block[0x7] << 2);
335         tmp *= 1000;
336         tmp += 512;
337         specs->chroma.redx = tmp/1024;
338         DPRINTK("         RedX:     0.%03d ", specs->chroma.redx);
339
340         tmp = ((block[5] & (3 << 4)) >> 4) | (block[0x8] << 2);
341         tmp *= 1000;
342         tmp += 512;
343         specs->chroma.redy = tmp/1024;
344         DPRINTK("RedY:     0.%03d\n", specs->chroma.redy);
345
346         tmp = ((block[5] & (3 << 2)) >> 2) | (block[0x9] << 2);
347         tmp *= 1000;
348         tmp += 512;
349         specs->chroma.greenx = tmp/1024;
350         DPRINTK("         GreenX:   0.%03d ", specs->chroma.greenx);
351
352         tmp = (block[5] & 3) | (block[0xa] << 2);
353         tmp *= 1000;
354         tmp += 512;
355         specs->chroma.greeny = tmp/1024;
356         DPRINTK("GreenY:   0.%03d\n", specs->chroma.greeny);
357
358         tmp = ((block[6] & (3 << 6)) >> 6) | (block[0xb] << 2);
359         tmp *= 1000;
360         tmp += 512;
361         specs->chroma.bluex = tmp/1024;
362         DPRINTK("         BlueX:    0.%03d ", specs->chroma.bluex);
363
364         tmp = ((block[6] & (3 << 4)) >> 4) | (block[0xc] << 2);
365         tmp *= 1000;
366         tmp += 512;
367         specs->chroma.bluey = tmp/1024;
368         DPRINTK("BlueY:    0.%03d\n", specs->chroma.bluey);
369
370         tmp = ((block[6] & (3 << 2)) >> 2) | (block[0xd] << 2);
371         tmp *= 1000;
372         tmp += 512;
373         specs->chroma.whitex = tmp/1024;
374         DPRINTK("         WhiteX:   0.%03d ", specs->chroma.whitex);
375
376         tmp = (block[6] & 3) | (block[0xe] << 2);
377         tmp *= 1000;
378         tmp += 512;
379         specs->chroma.whitey = tmp/1024;
380         DPRINTK("WhiteY:   0.%03d\n", specs->chroma.whitey);
381 }
382
383 static void calc_mode_timings(int xres, int yres, int refresh,
384                               struct fb_videomode *mode)
385 {
386         struct fb_var_screeninfo *var;
387
388         var = kzalloc(sizeof(struct fb_var_screeninfo), GFP_KERNEL);
389
390         if (var) {
391                 var->xres = xres;
392                 var->yres = yres;
393                 fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON,
394                             refresh, var, NULL);
395                 mode->xres = xres;
396                 mode->yres = yres;
397                 mode->pixclock = var->pixclock;
398                 mode->refresh = refresh;
399                 mode->left_margin = var->left_margin;
400                 mode->right_margin = var->right_margin;
401                 mode->upper_margin = var->upper_margin;
402                 mode->lower_margin = var->lower_margin;
403                 mode->hsync_len = var->hsync_len;
404                 mode->vsync_len = var->vsync_len;
405                 mode->vmode = 0;
406                 mode->sync = 0;
407                 kfree(var);
408         }
409 }
410
411 static int get_est_timing(unsigned char *block, struct fb_videomode *mode)
412 {
413         int num = 0;
414         unsigned char c;
415
416         c = block[0];
417         if (c&0x80) {
418                 calc_mode_timings(720, 400, 70, &mode[num]);
419                 mode[num++].flag = FB_MODE_IS_CALCULATED;
420                 DPRINTK("      720x400@70Hz\n");
421         }
422         if (c&0x40) {
423                 calc_mode_timings(720, 400, 88, &mode[num]);
424                 mode[num++].flag = FB_MODE_IS_CALCULATED;
425                 DPRINTK("      720x400@88Hz\n");
426         }
427         if (c&0x20) {
428                 mode[num++] = vesa_modes[3];
429                 DPRINTK("      640x480@60Hz\n");
430         }
431         if (c&0x10) {
432                 calc_mode_timings(640, 480, 67, &mode[num]);
433                 mode[num++].flag = FB_MODE_IS_CALCULATED;
434                 DPRINTK("      640x480@67Hz\n");
435         }
436         if (c&0x08) {
437                 mode[num++] = vesa_modes[4];
438                 DPRINTK("      640x480@72Hz\n");
439         }
440         if (c&0x04) {
441                 mode[num++] = vesa_modes[5];
442                 DPRINTK("      640x480@75Hz\n");
443         }
444         if (c&0x02) {
445                 mode[num++] = vesa_modes[7];
446                 DPRINTK("      800x600@56Hz\n");
447         }
448         if (c&0x01) {
449                 mode[num++] = vesa_modes[8];
450                 DPRINTK("      800x600@60Hz\n");
451         }
452
453         c = block[1];
454         if (c&0x80) {
455                 mode[num++] = vesa_modes[9];
456                 DPRINTK("      800x600@72Hz\n");
457         }
458         if (c&0x40) {
459                 mode[num++] = vesa_modes[10];
460                 DPRINTK("      800x600@75Hz\n");
461         }
462         if (c&0x20) {
463                 calc_mode_timings(832, 624, 75, &mode[num]);
464                 mode[num++].flag = FB_MODE_IS_CALCULATED;
465                 DPRINTK("      832x624@75Hz\n");
466         }
467         if (c&0x10) {
468                 mode[num++] = vesa_modes[12];
469                 DPRINTK("      1024x768@87Hz Interlaced\n");
470         }
471         if (c&0x08) {
472                 mode[num++] = vesa_modes[13];
473                 DPRINTK("      1024x768@60Hz\n");
474         }
475         if (c&0x04) {
476                 mode[num++] = vesa_modes[14];
477                 DPRINTK("      1024x768@70Hz\n");
478         }
479         if (c&0x02) {
480                 mode[num++] = vesa_modes[15];
481                 DPRINTK("      1024x768@75Hz\n");
482         }
483         if (c&0x01) {
484                 mode[num++] = vesa_modes[21];
485                 DPRINTK("      1280x1024@75Hz\n");
486         }
487         c = block[2];
488         if (c&0x80) {
489                 mode[num++] = vesa_modes[17];
490                 DPRINTK("      1152x870@75Hz\n");
491         }
492         DPRINTK("      Manufacturer's mask: %x\n",c&0x7F);
493         return num;
494 }
495
496 static int get_std_timing(unsigned char *block, struct fb_videomode *mode)
497 {
498         int xres, yres = 0, refresh, ratio, i;
499
500         xres = (block[0] + 31) * 8;
501         if (xres <= 256)
502                 return 0;
503
504         ratio = (block[1] & 0xc0) >> 6;
505         switch (ratio) {
506         case 0:
507                 yres = xres;
508                 break;
509         case 1:
510                 yres = (xres * 3)/4;
511                 break;
512         case 2:
513                 yres = (xres * 4)/5;
514                 break;
515         case 3:
516                 yres = (xres * 9)/16;
517                 break;
518         }
519         refresh = (block[1] & 0x3f) + 60;
520
521         DPRINTK("      %dx%d@%dHz\n", xres, yres, refresh);
522         for (i = 0; i < VESA_MODEDB_SIZE; i++) {
523                 if (vesa_modes[i].xres == xres &&
524                     vesa_modes[i].yres == yres &&
525                     vesa_modes[i].refresh == refresh) {
526                         *mode = vesa_modes[i];
527                         mode->flag |= FB_MODE_IS_STANDARD;
528                         return 1;
529                 }
530         }
531         calc_mode_timings(xres, yres, refresh, mode);
532         return 1;
533 }
534
535 static int get_dst_timing(unsigned char *block,
536                           struct fb_videomode *mode)
537 {
538         int j, num = 0;
539
540         for (j = 0; j < 6; j++, block += STD_TIMING_DESCRIPTION_SIZE)
541                 num += get_std_timing(block, &mode[num]);
542
543         return num;
544 }
545
546 static void get_detailed_timing(unsigned char *block,
547                                 struct fb_videomode *mode)
548 {
549         mode->xres = H_ACTIVE;
550         mode->yres = V_ACTIVE;
551         mode->pixclock = PIXEL_CLOCK;
552         mode->pixclock /= 1000;
553         mode->pixclock = KHZ2PICOS(mode->pixclock);
554         mode->right_margin = H_SYNC_OFFSET;
555         mode->left_margin = (H_ACTIVE + H_BLANKING) -
556                 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
557         mode->upper_margin = V_BLANKING - V_SYNC_OFFSET -
558                 V_SYNC_WIDTH;
559         mode->lower_margin = V_SYNC_OFFSET;
560         mode->hsync_len = H_SYNC_WIDTH;
561         mode->vsync_len = V_SYNC_WIDTH;
562         if (HSYNC_POSITIVE)
563                 mode->sync |= FB_SYNC_HOR_HIGH_ACT;
564         if (VSYNC_POSITIVE)
565                 mode->sync |= FB_SYNC_VERT_HIGH_ACT;
566         mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *
567                                      (V_ACTIVE + V_BLANKING));
568         if (INTERLACED) {
569                 mode->yres *= 2;
570                 mode->upper_margin *= 2;
571                 mode->lower_margin *= 2;
572                 mode->vsync_len *= 2;
573                 mode->vmode |= FB_VMODE_INTERLACED;
574         }
575         mode->flag = FB_MODE_IS_DETAILED;
576
577         DPRINTK("      %d MHz ",  PIXEL_CLOCK/1000000);
578         DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET,
579                H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING);
580         DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET,
581                V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING);
582         DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-",
583                (VSYNC_POSITIVE) ? "+" : "-");
584 }
585
586 /**
587  * fb_create_modedb - create video mode database
588  * @edid: EDID data
589  * @dbsize: database size
590  *
591  * RETURNS: struct fb_videomode, @dbsize contains length of database
592  *
593  * DESCRIPTION:
594  * This function builds a mode database using the contents of the EDID
595  * data
596  */
597 static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize)
598 {
599         struct fb_videomode *mode, *m;
600         unsigned char *block;
601         int num = 0, i, first = 1;
602
603         mode = kzalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
604         if (mode == NULL)
605                 return NULL;
606
607         if (edid == NULL || !edid_checksum(edid) ||
608             !edid_check_header(edid)) {
609                 kfree(mode);
610                 return NULL;
611         }
612
613         *dbsize = 0;
614
615         DPRINTK("   Detailed Timings\n");
616         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
617         for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
618                 if (!(block[0] == 0x00 && block[1] == 0x00)) {
619                         get_detailed_timing(block, &mode[num]);
620                         if (first) {
621                                 mode[num].flag |= FB_MODE_IS_FIRST;
622                                 first = 0;
623                         }
624                         num++;
625                 }
626         }
627
628         DPRINTK("   Supported VESA Modes\n");
629         block = edid + ESTABLISHED_TIMING_1;
630         num += get_est_timing(block, &mode[num]);
631
632         DPRINTK("   Standard Timings\n");
633         block = edid + STD_TIMING_DESCRIPTIONS_START;
634         for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE)
635                 num += get_std_timing(block, &mode[num]);
636
637         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
638         for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
639                 if (block[0] == 0x00 && block[1] == 0x00 && block[3] == 0xfa)
640                         num += get_dst_timing(block + 5, &mode[num]);
641         }
642
643         /* Yikes, EDID data is totally useless */
644         if (!num) {
645                 kfree(mode);
646                 return NULL;
647         }
648
649         *dbsize = num;
650         m = kmalloc(num * sizeof(struct fb_videomode), GFP_KERNEL);
651         if (!m)
652                 return mode;
653         memmove(m, mode, num * sizeof(struct fb_videomode));
654         kfree(mode);
655         return m;
656 }
657
658 /**
659  * fb_destroy_modedb - destroys mode database
660  * @modedb: mode database to destroy
661  *
662  * DESCRIPTION:
663  * Destroy mode database created by fb_create_modedb
664  */
665 void fb_destroy_modedb(struct fb_videomode *modedb)
666 {
667         kfree(modedb);
668 }
669
670 static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
671 {
672         int i, retval = 1;
673         unsigned char *block;
674
675         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
676
677         DPRINTK("      Monitor Operating Limits: ");
678
679         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
680                 if (edid_is_limits_block(block)) {
681                         specs->hfmin = H_MIN_RATE * 1000;
682                         specs->hfmax = H_MAX_RATE * 1000;
683                         specs->vfmin = V_MIN_RATE;
684                         specs->vfmax = V_MAX_RATE;
685                         specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;
686                         specs->gtf = (GTF_SUPPORT) ? 1 : 0;
687                         retval = 0;
688                         DPRINTK("From EDID\n");
689                         break;
690                 }
691         }
692
693         /* estimate monitor limits based on modes supported */
694         if (retval) {
695                 struct fb_videomode *modes, *mode;
696                 int num_modes, hz, hscan, pixclock;
697                 int vtotal, htotal;
698
699                 modes = fb_create_modedb(edid, &num_modes);
700                 if (!modes) {
701                         DPRINTK("None Available\n");
702                         return 1;
703                 }
704
705                 retval = 0;
706                 for (i = 0; i < num_modes; i++) {
707                         mode = &modes[i];
708                         pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
709                         htotal = mode->xres + mode->right_margin + mode->hsync_len
710                                 + mode->left_margin;
711                         vtotal = mode->yres + mode->lower_margin + mode->vsync_len
712                                 + mode->upper_margin;
713
714                         if (mode->vmode & FB_VMODE_INTERLACED)
715                                 vtotal /= 2;
716
717                         if (mode->vmode & FB_VMODE_DOUBLE)
718                                 vtotal *= 2;
719
720                         hscan = (pixclock + htotal / 2) / htotal;
721                         hscan = (hscan + 500) / 1000 * 1000;
722                         hz = (hscan + vtotal / 2) / vtotal;
723
724                         if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
725                                 specs->dclkmax = pixclock;
726
727                         if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
728                                 specs->dclkmin = pixclock;
729
730                         if (specs->hfmax == 0 || specs->hfmax < hscan)
731                                 specs->hfmax = hscan;
732
733                         if (specs->hfmin == 0 || specs->hfmin > hscan)
734                                 specs->hfmin = hscan;
735
736                         if (specs->vfmax == 0 || specs->vfmax < hz)
737                                 specs->vfmax = hz;
738
739                         if (specs->vfmin == 0 || specs->vfmin > hz)
740                                 specs->vfmin = hz;
741                 }
742                 DPRINTK("Extrapolated\n");
743                 fb_destroy_modedb(modes);
744         }
745         DPRINTK("           H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",
746                 specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,
747                 specs->vfmax, specs->dclkmax/1000000);
748         return retval;
749 }
750
751 static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
752 {
753         unsigned char c, *block;
754
755         block = edid + EDID_STRUCT_DISPLAY;
756
757         fb_get_monitor_limits(edid, specs);
758
759         c = block[0] & 0x80;
760         specs->input = 0;
761         if (c) {
762                 specs->input |= FB_DISP_DDI;
763                 DPRINTK("      Digital Display Input");
764         } else {
765                 DPRINTK("      Analog Display Input: Input Voltage - ");
766                 switch ((block[0] & 0x60) >> 5) {
767                 case 0:
768                         DPRINTK("0.700V/0.300V");
769                         specs->input |= FB_DISP_ANA_700_300;
770                         break;
771                 case 1:
772                         DPRINTK("0.714V/0.286V");
773                         specs->input |= FB_DISP_ANA_714_286;
774                         break;
775                 case 2:
776                         DPRINTK("1.000V/0.400V");
777                         specs->input |= FB_DISP_ANA_1000_400;
778                         break;
779                 case 3:
780                         DPRINTK("0.700V/0.000V");
781                         specs->input |= FB_DISP_ANA_700_000;
782                         break;
783                 }
784         }
785         DPRINTK("\n      Sync: ");
786         c = block[0] & 0x10;
787         if (c)
788                 DPRINTK("      Configurable signal level\n");
789         c = block[0] & 0x0f;
790         specs->signal = 0;
791         if (c & 0x10) {
792                 DPRINTK("Blank to Blank ");
793                 specs->signal |= FB_SIGNAL_BLANK_BLANK;
794         }
795         if (c & 0x08) {
796                 DPRINTK("Separate ");
797                 specs->signal |= FB_SIGNAL_SEPARATE;
798         }
799         if (c & 0x04) {
800                 DPRINTK("Composite ");
801                 specs->signal |= FB_SIGNAL_COMPOSITE;
802         }
803         if (c & 0x02) {
804                 DPRINTK("Sync on Green ");
805                 specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
806         }
807         if (c & 0x01) {
808                 DPRINTK("Serration on ");
809                 specs->signal |= FB_SIGNAL_SERRATION_ON;
810         }
811         DPRINTK("\n");
812         specs->max_x = block[1];
813         specs->max_y = block[2];
814         DPRINTK("      Max H-size in cm: ");
815         if (specs->max_x)
816                 DPRINTK("%d\n", specs->max_x);
817         else
818                 DPRINTK("variable\n");
819         DPRINTK("      Max V-size in cm: ");
820         if (specs->max_y)
821                 DPRINTK("%d\n", specs->max_y);
822         else
823                 DPRINTK("variable\n");
824
825         c = block[3];
826         specs->gamma = c+100;
827         DPRINTK("      Gamma: ");
828         DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
829
830         get_dpms_capabilities(block[4], specs);
831
832         switch ((block[4] & 0x18) >> 3) {
833         case 0:
834                 DPRINTK("      Monochrome/Grayscale\n");
835                 specs->input |= FB_DISP_MONO;
836                 break;
837         case 1:
838                 DPRINTK("      RGB Color Display\n");
839                 specs->input |= FB_DISP_RGB;
840                 break;
841         case 2:
842                 DPRINTK("      Non-RGB Multicolor Display\n");
843                 specs->input |= FB_DISP_MULTI;
844                 break;
845         default:
846                 DPRINTK("      Unknown\n");
847                 specs->input |= FB_DISP_UNKNOWN;
848                 break;
849         }
850
851         get_chroma(block, specs);
852
853         specs->misc = 0;
854         c = block[4] & 0x7;
855         if (c & 0x04) {
856                 DPRINTK("      Default color format is primary\n");
857                 specs->misc |= FB_MISC_PRIM_COLOR;
858         }
859         if (c & 0x02) {
860                 DPRINTK("      First DETAILED Timing is preferred\n");
861                 specs->misc |= FB_MISC_1ST_DETAIL;
862         }
863         if (c & 0x01) {
864                 printk("      Display is GTF capable\n");
865                 specs->gtf = 1;
866         }
867 }
868
869 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
870 {
871         int i;
872         unsigned char *block;
873
874         if (edid == NULL || var == NULL)
875                 return 1;
876
877         if (!(edid_checksum(edid)))
878                 return 1;
879
880         if (!(edid_check_header(edid)))
881                 return 1;
882
883         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
884
885         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
886                 if (edid_is_timing_block(block)) {
887                         var->xres = var->xres_virtual = H_ACTIVE;
888                         var->yres = var->yres_virtual = V_ACTIVE;
889                         var->height = var->width = 0;
890                         var->right_margin = H_SYNC_OFFSET;
891                         var->left_margin = (H_ACTIVE + H_BLANKING) -
892                                 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
893                         var->upper_margin = V_BLANKING - V_SYNC_OFFSET -
894                                 V_SYNC_WIDTH;
895                         var->lower_margin = V_SYNC_OFFSET;
896                         var->hsync_len = H_SYNC_WIDTH;
897                         var->vsync_len = V_SYNC_WIDTH;
898                         var->pixclock = PIXEL_CLOCK;
899                         var->pixclock /= 1000;
900                         var->pixclock = KHZ2PICOS(var->pixclock);
901
902                         if (HSYNC_POSITIVE)
903                                 var->sync |= FB_SYNC_HOR_HIGH_ACT;
904                         if (VSYNC_POSITIVE)
905                                 var->sync |= FB_SYNC_VERT_HIGH_ACT;
906                         return 0;
907                 }
908         }
909         return 1;
910 }
911
912 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
913 {
914         unsigned char *block;
915         int i, found = 0;
916
917         if (edid == NULL)
918                 return;
919
920         if (!(edid_checksum(edid)))
921                 return;
922
923         if (!(edid_check_header(edid)))
924                 return;
925
926         memset(specs, 0, sizeof(struct fb_monspecs));
927
928         specs->version = edid[EDID_STRUCT_VERSION];
929         specs->revision = edid[EDID_STRUCT_REVISION];
930
931         DPRINTK("========================================\n");
932         DPRINTK("Display Information (EDID)\n");
933         DPRINTK("========================================\n");
934         DPRINTK("   EDID Version %d.%d\n", (int) specs->version,
935                (int) specs->revision);
936
937         parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);
938
939         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
940         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
941                 if (edid_is_serial_block(block)) {
942                         copy_string(block, specs->serial_no);
943                         DPRINTK("   Serial Number: %s\n", specs->serial_no);
944                 } else if (edid_is_ascii_block(block)) {
945                         copy_string(block, specs->ascii);
946                         DPRINTK("   ASCII Block: %s\n", specs->ascii);
947                 } else if (edid_is_monitor_block(block)) {
948                         copy_string(block, specs->monitor);
949                         DPRINTK("   Monitor Name: %s\n", specs->monitor);
950                 }
951         }
952
953         DPRINTK("   Display Characteristics:\n");
954         get_monspecs(edid, specs);
955
956         specs->modedb = fb_create_modedb(edid, &specs->modedb_len);
957
958         /*
959          * Workaround for buggy EDIDs that sets that the first
960          * detailed timing is preferred but has not detailed
961          * timing specified
962          */
963         for (i = 0; i < specs->modedb_len; i++) {
964                 if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {
965                         found = 1;
966                         break;
967                 }
968         }
969
970         if (!found)
971                 specs->misc &= ~FB_MISC_1ST_DETAIL;
972
973         DPRINTK("========================================\n");
974 }
975
976 /*
977  * VESA Generalized Timing Formula (GTF)
978  */
979
980 #define FLYBACK                     550
981 #define V_FRONTPORCH                1
982 #define H_OFFSET                    40
983 #define H_SCALEFACTOR               20
984 #define H_BLANKSCALE                128
985 #define H_GRADIENT                  600
986 #define C_VAL                       30
987 #define M_VAL                       300
988
989 struct __fb_timings {
990         u32 dclk;
991         u32 hfreq;
992         u32 vfreq;
993         u32 hactive;
994         u32 vactive;
995         u32 hblank;
996         u32 vblank;
997         u32 htotal;
998         u32 vtotal;
999 };
1000
1001 /**
1002  * fb_get_vblank - get vertical blank time
1003  * @hfreq: horizontal freq
1004  *
1005  * DESCRIPTION:
1006  * vblank = right_margin + vsync_len + left_margin
1007  *
1008  *    given: right_margin = 1 (V_FRONTPORCH)
1009  *           vsync_len    = 3
1010  *           flyback      = 550
1011  *
1012  *                          flyback * hfreq
1013  *           left_margin  = --------------- - vsync_len
1014  *                           1000000
1015  */
1016 static u32 fb_get_vblank(u32 hfreq)
1017 {
1018         u32 vblank;
1019
1020         vblank = (hfreq * FLYBACK)/1000;
1021         vblank = (vblank + 500)/1000;
1022         return (vblank + V_FRONTPORCH);
1023 }
1024
1025 /**
1026  * fb_get_hblank_by_freq - get horizontal blank time given hfreq
1027  * @hfreq: horizontal freq
1028  * @xres: horizontal resolution in pixels
1029  *
1030  * DESCRIPTION:
1031  *
1032  *           xres * duty_cycle
1033  * hblank = ------------------
1034  *           100 - duty_cycle
1035  *
1036  * duty cycle = percent of htotal assigned to inactive display
1037  * duty cycle = C - (M/Hfreq)
1038  *
1039  * where: C = ((offset - scale factor) * blank_scale)
1040  *            -------------------------------------- + scale factor
1041  *                        256
1042  *        M = blank_scale * gradient
1043  *
1044  */
1045 static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
1046 {
1047         u32 c_val, m_val, duty_cycle, hblank;
1048
1049         c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 +
1050                  H_SCALEFACTOR) * 1000;
1051         m_val = (H_BLANKSCALE * H_GRADIENT)/256;
1052         m_val = (m_val * 1000000)/hfreq;
1053         duty_cycle = c_val - m_val;
1054         hblank = (xres * duty_cycle)/(100000 - duty_cycle);
1055         return (hblank);
1056 }
1057
1058 /**
1059  * fb_get_hblank_by_dclk - get horizontal blank time given pixelclock
1060  * @dclk: pixelclock in Hz
1061  * @xres: horizontal resolution in pixels
1062  *
1063  * DESCRIPTION:
1064  *
1065  *           xres * duty_cycle
1066  * hblank = ------------------
1067  *           100 - duty_cycle
1068  *
1069  * duty cycle = percent of htotal assigned to inactive display
1070  * duty cycle = C - (M * h_period)
1071  *
1072  * where: h_period = SQRT(100 - C + (0.4 * xres * M)/dclk) + C - 100
1073  *                   -----------------------------------------------
1074  *                                    2 * M
1075  *        M = 300;
1076  *        C = 30;
1077
1078  */
1079 static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)
1080 {
1081         u32 duty_cycle, h_period, hblank;
1082
1083         dclk /= 1000;
1084         h_period = 100 - C_VAL;
1085         h_period *= h_period;
1086         h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);
1087         h_period *= 10000;
1088
1089         h_period = int_sqrt(h_period);
1090         h_period -= (100 - C_VAL) * 100;
1091         h_period *= 1000;
1092         h_period /= 2 * M_VAL;
1093
1094         duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;
1095         hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;
1096         hblank &= ~15;
1097         return (hblank);
1098 }
1099
1100 /**
1101  * fb_get_hfreq - estimate hsync
1102  * @vfreq: vertical refresh rate
1103  * @yres: vertical resolution
1104  *
1105  * DESCRIPTION:
1106  *
1107  *          (yres + front_port) * vfreq * 1000000
1108  * hfreq = -------------------------------------
1109  *          (1000000 - (vfreq * FLYBACK)
1110  *
1111  */
1112
1113 static u32 fb_get_hfreq(u32 vfreq, u32 yres)
1114 {
1115         u32 divisor, hfreq;
1116
1117         divisor = (1000000 - (vfreq * FLYBACK))/1000;
1118         hfreq = (yres + V_FRONTPORCH) * vfreq  * 1000;
1119         return (hfreq/divisor);
1120 }
1121
1122 static void fb_timings_vfreq(struct __fb_timings *timings)
1123 {
1124         timings->hfreq = fb_get_hfreq(timings->vfreq, timings->vactive);
1125         timings->vblank = fb_get_vblank(timings->hfreq);
1126         timings->vtotal = timings->vactive + timings->vblank;
1127         timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1128                                                  timings->hactive);
1129         timings->htotal = timings->hactive + timings->hblank;
1130         timings->dclk = timings->htotal * timings->hfreq;
1131 }
1132
1133 static void fb_timings_hfreq(struct __fb_timings *timings)
1134 {
1135         timings->vblank = fb_get_vblank(timings->hfreq);
1136         timings->vtotal = timings->vactive + timings->vblank;
1137         timings->vfreq = timings->hfreq/timings->vtotal;
1138         timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1139                                                  timings->hactive);
1140         timings->htotal = timings->hactive + timings->hblank;
1141         timings->dclk = timings->htotal * timings->hfreq;
1142 }
1143
1144 static void fb_timings_dclk(struct __fb_timings *timings)
1145 {
1146         timings->hblank = fb_get_hblank_by_dclk(timings->dclk,
1147                                                 timings->hactive);
1148         timings->htotal = timings->hactive + timings->hblank;
1149         timings->hfreq = timings->dclk/timings->htotal;
1150         timings->vblank = fb_get_vblank(timings->hfreq);
1151         timings->vtotal = timings->vactive + timings->vblank;
1152         timings->vfreq = timings->hfreq/timings->vtotal;
1153 }
1154
1155 /*
1156  * fb_get_mode - calculates video mode using VESA GTF
1157  * @flags: if: 0 - maximize vertical refresh rate
1158  *             1 - vrefresh-driven calculation;
1159  *             2 - hscan-driven calculation;
1160  *             3 - pixelclock-driven calculation;
1161  * @val: depending on @flags, ignored, vrefresh, hsync or pixelclock
1162  * @var: pointer to fb_var_screeninfo
1163  * @info: pointer to fb_info
1164  *
1165  * DESCRIPTION:
1166  * Calculates video mode based on monitor specs using VESA GTF.
1167  * The GTF is best for VESA GTF compliant monitors but is
1168  * specifically formulated to work for older monitors as well.
1169  *
1170  * If @flag==0, the function will attempt to maximize the
1171  * refresh rate.  Otherwise, it will calculate timings based on
1172  * the flag and accompanying value.
1173  *
1174  * If FB_IGNOREMON bit is set in @flags, monitor specs will be
1175  * ignored and @var will be filled with the calculated timings.
1176  *
1177  * All calculations are based on the VESA GTF Spreadsheet
1178  * available at VESA's public ftp (http://www.vesa.org).
1179  *
1180  * NOTES:
1181  * The timings generated by the GTF will be different from VESA
1182  * DMT.  It might be a good idea to keep a table of standard
1183  * VESA modes as well.  The GTF may also not work for some displays,
1184  * such as, and especially, analog TV.
1185  *
1186  * REQUIRES:
1187  * A valid info->monspecs, otherwise 'safe numbers' will be used.
1188  */
1189 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)
1190 {
1191         struct __fb_timings *timings;
1192         u32 interlace = 1, dscan = 1;
1193         u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;
1194
1195
1196         timings = kzalloc(sizeof(struct __fb_timings), GFP_KERNEL);
1197
1198         if (!timings)
1199                 return -ENOMEM;
1200
1201         /*
1202          * If monspecs are invalid, use values that are enough
1203          * for 640x480@60
1204          */
1205         if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||
1206             !info->monspecs.dclkmax ||
1207             info->monspecs.hfmax < info->monspecs.hfmin ||
1208             info->monspecs.vfmax < info->monspecs.vfmin ||
1209             info->monspecs.dclkmax < info->monspecs.dclkmin) {
1210                 hfmin = 29000; hfmax = 30000;
1211                 vfmin = 60; vfmax = 60;
1212                 dclkmin = 0; dclkmax = 25000000;
1213         } else {
1214                 hfmin = info->monspecs.hfmin;
1215                 hfmax = info->monspecs.hfmax;
1216                 vfmin = info->monspecs.vfmin;
1217                 vfmax = info->monspecs.vfmax;
1218                 dclkmin = info->monspecs.dclkmin;
1219                 dclkmax = info->monspecs.dclkmax;
1220         }
1221
1222         timings->hactive = var->xres;
1223         timings->vactive = var->yres;
1224         if (var->vmode & FB_VMODE_INTERLACED) {
1225                 timings->vactive /= 2;
1226                 interlace = 2;
1227         }
1228         if (var->vmode & FB_VMODE_DOUBLE) {
1229                 timings->vactive *= 2;
1230                 dscan = 2;
1231         }
1232
1233         switch (flags & ~FB_IGNOREMON) {
1234         case FB_MAXTIMINGS: /* maximize refresh rate */
1235                 timings->hfreq = hfmax;
1236                 fb_timings_hfreq(timings);
1237                 if (timings->vfreq > vfmax) {
1238                         timings->vfreq = vfmax;
1239                         fb_timings_vfreq(timings);
1240                 }
1241                 if (timings->dclk > dclkmax) {
1242                         timings->dclk = dclkmax;
1243                         fb_timings_dclk(timings);
1244                 }
1245                 break;
1246         case FB_VSYNCTIMINGS: /* vrefresh driven */
1247                 timings->vfreq = val;
1248                 fb_timings_vfreq(timings);
1249                 break;
1250         case FB_HSYNCTIMINGS: /* hsync driven */
1251                 timings->hfreq = val;
1252                 fb_timings_hfreq(timings);
1253                 break;
1254         case FB_DCLKTIMINGS: /* pixelclock driven */
1255                 timings->dclk = PICOS2KHZ(val) * 1000;
1256                 fb_timings_dclk(timings);
1257                 break;
1258         default:
1259                 err = -EINVAL;
1260
1261         }
1262
1263         if (err || (!(flags & FB_IGNOREMON) &&
1264             (timings->vfreq < vfmin || timings->vfreq > vfmax ||
1265              timings->hfreq < hfmin || timings->hfreq > hfmax ||
1266              timings->dclk < dclkmin || timings->dclk > dclkmax))) {
1267                 err = -EINVAL;
1268         } else {
1269                 var->pixclock = KHZ2PICOS(timings->dclk/1000);
1270                 var->hsync_len = (timings->htotal * 8)/100;
1271                 var->right_margin = (timings->hblank/2) - var->hsync_len;
1272                 var->left_margin = timings->hblank - var->right_margin -
1273                         var->hsync_len;
1274                 var->vsync_len = (3 * interlace)/dscan;
1275                 var->lower_margin = (1 * interlace)/dscan;
1276                 var->upper_margin = (timings->vblank * interlace)/dscan -
1277                         (var->vsync_len + var->lower_margin);
1278         }
1279
1280         kfree(timings);
1281         return err;
1282 }
1283 #else
1284 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
1285 {
1286         return 1;
1287 }
1288 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1289 {
1290         specs = NULL;
1291 }
1292 void fb_destroy_modedb(struct fb_videomode *modedb)
1293 {
1294 }
1295 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
1296                 struct fb_info *info)
1297 {
1298         return -EINVAL;
1299 }
1300 #endif /* CONFIG_FB_MODE_HELPERS */
1301
1302 /*
1303  * fb_validate_mode - validates var against monitor capabilities
1304  * @var: pointer to fb_var_screeninfo
1305  * @info: pointer to fb_info
1306  *
1307  * DESCRIPTION:
1308  * Validates video mode against monitor capabilities specified in
1309  * info->monspecs.
1310  *
1311  * REQUIRES:
1312  * A valid info->monspecs.
1313  */
1314 int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
1315 {
1316         u32 hfreq, vfreq, htotal, vtotal, pixclock;
1317         u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
1318
1319         /*
1320          * If monspecs are invalid, use values that are enough
1321          * for 640x480@60
1322          */
1323         if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
1324             !info->monspecs.dclkmax ||
1325             info->monspecs.hfmax < info->monspecs.hfmin ||
1326             info->monspecs.vfmax < info->monspecs.vfmin ||
1327             info->monspecs.dclkmax < info->monspecs.dclkmin) {
1328                 hfmin = 29000; hfmax = 30000;
1329                 vfmin = 60; vfmax = 60;
1330                 dclkmin = 0; dclkmax = 25000000;
1331         } else {
1332                 hfmin = info->monspecs.hfmin;
1333                 hfmax = info->monspecs.hfmax;
1334                 vfmin = info->monspecs.vfmin;
1335                 vfmax = info->monspecs.vfmax;
1336                 dclkmin = info->monspecs.dclkmin;
1337                 dclkmax = info->monspecs.dclkmax;
1338         }
1339
1340         if (!var->pixclock)
1341                 return -EINVAL;
1342         pixclock = PICOS2KHZ(var->pixclock) * 1000;
1343
1344         htotal = var->xres + var->right_margin + var->hsync_len +
1345                 var->left_margin;
1346         vtotal = var->yres + var->lower_margin + var->vsync_len +
1347                 var->upper_margin;
1348
1349         if (var->vmode & FB_VMODE_INTERLACED)
1350                 vtotal /= 2;
1351         if (var->vmode & FB_VMODE_DOUBLE)
1352                 vtotal *= 2;
1353
1354         hfreq = pixclock/htotal;
1355         hfreq = (hfreq + 500) / 1000 * 1000;
1356
1357         vfreq = hfreq/vtotal;
1358
1359         return (vfreq < vfmin || vfreq > vfmax ||
1360                 hfreq < hfmin || hfreq > hfmax ||
1361                 pixclock < dclkmin || pixclock > dclkmax) ?
1362                 -EINVAL : 0;
1363 }
1364
1365 #if defined(CONFIG_FIRMWARE_EDID) && defined(CONFIG_X86)
1366
1367 /*
1368  * We need to ensure that the EDID block is only returned for
1369  * the primary graphics adapter.
1370  */
1371
1372 const unsigned char *fb_firmware_edid(struct device *device)
1373 {
1374         struct pci_dev *dev = NULL;
1375         struct resource *res = NULL;
1376         unsigned char *edid = NULL;
1377
1378         if (device)
1379                 dev = to_pci_dev(device);
1380
1381         if (dev)
1382                 res = &dev->resource[PCI_ROM_RESOURCE];
1383
1384         if (res && res->flags & IORESOURCE_ROM_SHADOW)
1385                 edid = edid_info.dummy;
1386
1387         return edid;
1388 }
1389 #else
1390 const unsigned char *fb_firmware_edid(struct device *device)
1391 {
1392         return NULL;
1393 }
1394 #endif
1395 EXPORT_SYMBOL(fb_firmware_edid);
1396
1397 EXPORT_SYMBOL(fb_parse_edid);
1398 EXPORT_SYMBOL(fb_edid_to_monspecs);
1399 EXPORT_SYMBOL(fb_get_mode);
1400 EXPORT_SYMBOL(fb_validate_mode);
1401 EXPORT_SYMBOL(fb_destroy_modedb);