Merge master.kernel.org:/home/rmk/linux-2.6-arm
[linux-2.6] / 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 <video/edid.h>
33 #ifdef CONFIG_PPC_OF
34 #include <asm/prom.h>
35 #include <asm/pci-bridge.h>
36 #endif
37 #include "edid.h"
38
39 /* 
40  * EDID parser
41  */
42
43 #undef DEBUG  /* define this for verbose EDID parsing output */
44
45 #ifdef DEBUG
46 #define DPRINTK(fmt, args...) printk(fmt,## args)
47 #else
48 #define DPRINTK(fmt, args...)
49 #endif
50
51 #define FBMON_FIX_HEADER  1
52 #define FBMON_FIX_INPUT   2
53 #define FBMON_FIX_TIMINGS 3
54
55 #ifdef CONFIG_FB_MODE_HELPERS
56 struct broken_edid {
57         u8  manufacturer[4];
58         u32 model;
59         u32 fix;
60 };
61
62 static const struct broken_edid brokendb[] = {
63         /* DEC FR-PCXAV-YZ */
64         {
65                 .manufacturer = "DEC",
66                 .model        = 0x073a,
67                 .fix          = FBMON_FIX_HEADER,
68         },
69         /* ViewSonic PF775a */
70         {
71                 .manufacturer = "VSC",
72                 .model        = 0x5a44,
73                 .fix          = FBMON_FIX_INPUT,
74         },
75         /* Sharp UXGA? */
76         {
77                 .manufacturer = "SHP",
78                 .model        = 0x138e,
79                 .fix          = FBMON_FIX_TIMINGS,
80         },
81 };
82
83 static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
84         0xff, 0xff, 0xff, 0x00
85 };
86
87 static void copy_string(unsigned char *c, unsigned char *s)
88 {
89   int i;
90   c = c + 5;
91   for (i = 0; (i < 13 && *c != 0x0A); i++)
92     *(s++) = *(c++);
93   *s = 0;
94   while (i-- && (*--s == 0x20)) *s = 0;
95 }
96
97 static int edid_is_serial_block(unsigned char *block)
98 {
99         if ((block[0] == 0x00) && (block[1] == 0x00) &&
100             (block[2] == 0x00) && (block[3] == 0xff) &&
101             (block[4] == 0x00))
102                 return 1;
103         else
104                 return 0;
105 }
106
107 static int edid_is_ascii_block(unsigned char *block)
108 {
109         if ((block[0] == 0x00) && (block[1] == 0x00) &&
110             (block[2] == 0x00) && (block[3] == 0xfe) &&
111             (block[4] == 0x00))
112                 return 1;
113         else
114                 return 0;
115 }
116
117 static int edid_is_limits_block(unsigned char *block)
118 {
119         if ((block[0] == 0x00) && (block[1] == 0x00) &&
120             (block[2] == 0x00) && (block[3] == 0xfd) &&
121             (block[4] == 0x00))
122                 return 1;
123         else
124                 return 0;
125 }
126
127 static int edid_is_monitor_block(unsigned char *block)
128 {
129         if ((block[0] == 0x00) && (block[1] == 0x00) &&
130             (block[2] == 0x00) && (block[3] == 0xfc) &&
131             (block[4] == 0x00))
132                 return 1;
133         else
134                 return 0;
135 }
136
137 static int edid_is_timing_block(unsigned char *block)
138 {
139         if ((block[0] != 0x00) || (block[1] != 0x00) ||
140             (block[2] != 0x00) || (block[4] != 0x00))
141                 return 1;
142         else
143                 return 0;
144 }
145
146 static int check_edid(unsigned char *edid)
147 {
148         unsigned char *block = edid + ID_MANUFACTURER_NAME, manufacturer[4];
149         unsigned char *b;
150         u32 model;
151         int i, fix = 0, ret = 0;
152
153         manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
154         manufacturer[1] = ((block[0] & 0x03) << 3) +
155                 ((block[1] & 0xe0) >> 5) + '@';
156         manufacturer[2] = (block[1] & 0x1f) + '@';
157         manufacturer[3] = 0;
158         model = block[2] + (block[3] << 8);
159
160         for (i = 0; i < ARRAY_SIZE(brokendb); i++) {
161                 if (!strncmp(manufacturer, brokendb[i].manufacturer, 4) &&
162                         brokendb[i].model == model) {
163                         fix = brokendb[i].fix;
164                         break;
165                 }
166         }
167
168         switch (fix) {
169         case FBMON_FIX_HEADER:
170                 for (i = 0; i < 8; i++) {
171                         if (edid[i] != edid_v1_header[i]) {
172                                 ret = fix;
173                                 break;
174                         }
175                 }
176                 break;
177         case FBMON_FIX_INPUT:
178                 b = edid + EDID_STRUCT_DISPLAY;
179                 /* Only if display is GTF capable will
180                    the input type be reset to analog */
181                 if (b[4] & 0x01 && b[0] & 0x80)
182                         ret = fix;
183                 break;
184         case FBMON_FIX_TIMINGS:
185                 b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
186                 ret = fix;
187
188                 for (i = 0; i < 4; i++) {
189                         if (edid_is_limits_block(b)) {
190                                 ret = 0;
191                                 break;
192                         }
193
194                         b += DETAILED_TIMING_DESCRIPTION_SIZE;
195                 }
196
197                 break;
198         }
199
200         if (ret)
201                 printk("fbmon: The EDID Block of "
202                        "Manufacturer: %s Model: 0x%x is known to "
203                        "be broken,\n",  manufacturer, model);
204
205         return ret;
206 }
207
208 static void fix_edid(unsigned char *edid, int fix)
209 {
210         int i;
211         unsigned char *b, csum = 0;
212
213         switch (fix) {
214         case FBMON_FIX_HEADER:
215                 printk("fbmon: trying a header reconstruct\n");
216                 memcpy(edid, edid_v1_header, 8);
217                 break;
218         case FBMON_FIX_INPUT:
219                 printk("fbmon: trying to fix input type\n");
220                 b = edid + EDID_STRUCT_DISPLAY;
221                 b[0] &= ~0x80;
222                 edid[127] += 0x80;
223                 break;
224         case FBMON_FIX_TIMINGS:
225                 printk("fbmon: trying to fix monitor timings\n");
226                 b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
227                 for (i = 0; i < 4; i++) {
228                         if (!(edid_is_serial_block(b) ||
229                               edid_is_ascii_block(b) ||
230                               edid_is_monitor_block(b) ||
231                               edid_is_timing_block(b))) {
232                                 b[0] = 0x00;
233                                 b[1] = 0x00;
234                                 b[2] = 0x00;
235                                 b[3] = 0xfd;
236                                 b[4] = 0x00;
237                                 b[5] = 60;   /* vfmin */
238                                 b[6] = 60;   /* vfmax */
239                                 b[7] = 30;   /* hfmin */
240                                 b[8] = 75;   /* hfmax */
241                                 b[9] = 17;   /* pixclock - 170 MHz*/
242                                 b[10] = 0;   /* GTF */
243                                 break;
244                         }
245
246                         b += DETAILED_TIMING_DESCRIPTION_SIZE;
247                 }
248
249                 for (i = 0; i < EDID_LENGTH - 1; i++)
250                         csum += edid[i];
251
252                 edid[127] = 256 - csum;
253                 break;
254         }
255 }
256
257 static int edid_checksum(unsigned char *edid)
258 {
259         unsigned char i, csum = 0, all_null = 0;
260         int err = 0, fix = check_edid(edid);
261
262         if (fix)
263                 fix_edid(edid, fix);
264
265         for (i = 0; i < EDID_LENGTH; i++) {
266                 csum += edid[i];
267                 all_null |= edid[i];
268         }
269
270         if (csum == 0x00 && all_null) {
271                 /* checksum passed, everything's good */
272                 err = 1;
273         }
274
275         return err;
276 }
277
278 static int edid_check_header(unsigned char *edid)
279 {
280         int i, err = 1, fix = check_edid(edid);
281
282         if (fix)
283                 fix_edid(edid, fix);
284
285         for (i = 0; i < 8; i++) {
286                 if (edid[i] != edid_v1_header[i])
287                         err = 0;
288         }
289
290         return err;
291 }
292
293 static void parse_vendor_block(unsigned char *block, struct fb_monspecs *specs)
294 {
295         specs->manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
296         specs->manufacturer[1] = ((block[0] & 0x03) << 3) +
297                 ((block[1] & 0xe0) >> 5) + '@';
298         specs->manufacturer[2] = (block[1] & 0x1f) + '@';
299         specs->manufacturer[3] = 0;
300         specs->model = block[2] + (block[3] << 8);
301         specs->serial = block[4] + (block[5] << 8) +
302                (block[6] << 16) + (block[7] << 24);
303         specs->year = block[9] + 1990;
304         specs->week = block[8];
305         DPRINTK("   Manufacturer: %s\n", specs->manufacturer);
306         DPRINTK("   Model: %x\n", specs->model);
307         DPRINTK("   Serial#: %u\n", specs->serial);
308         DPRINTK("   Year: %u Week %u\n", specs->year, specs->week);
309 }
310
311 static void get_dpms_capabilities(unsigned char flags,
312                                   struct fb_monspecs *specs)
313 {
314         specs->dpms = 0;
315         if (flags & DPMS_ACTIVE_OFF)
316                 specs->dpms |= FB_DPMS_ACTIVE_OFF;
317         if (flags & DPMS_SUSPEND)
318                 specs->dpms |= FB_DPMS_SUSPEND;
319         if (flags & DPMS_STANDBY)
320                 specs->dpms |= FB_DPMS_STANDBY;
321         DPRINTK("      DPMS: Active %s, Suspend %s, Standby %s\n",
322                (flags & DPMS_ACTIVE_OFF) ? "yes" : "no",
323                (flags & DPMS_SUSPEND)    ? "yes" : "no",
324                (flags & DPMS_STANDBY)    ? "yes" : "no");
325 }
326         
327 static void get_chroma(unsigned char *block, struct fb_monspecs *specs)
328 {
329         int tmp;
330
331         DPRINTK("      Chroma\n");
332         /* Chromaticity data */
333         tmp = ((block[5] & (3 << 6)) >> 6) | (block[0x7] << 2);
334         tmp *= 1000;
335         tmp += 512;
336         specs->chroma.redx = tmp/1024;
337         DPRINTK("         RedX:     0.%03d ", specs->chroma.redx);
338
339         tmp = ((block[5] & (3 << 4)) >> 4) | (block[0x8] << 2);
340         tmp *= 1000;
341         tmp += 512;
342         specs->chroma.redy = tmp/1024;
343         DPRINTK("RedY:     0.%03d\n", specs->chroma.redy);
344
345         tmp = ((block[5] & (3 << 2)) >> 2) | (block[0x9] << 2);
346         tmp *= 1000;
347         tmp += 512;
348         specs->chroma.greenx = tmp/1024;
349         DPRINTK("         GreenX:   0.%03d ", specs->chroma.greenx);
350
351         tmp = (block[5] & 3) | (block[0xa] << 2);
352         tmp *= 1000;
353         tmp += 512;
354         specs->chroma.greeny = tmp/1024;
355         DPRINTK("GreenY:   0.%03d\n", specs->chroma.greeny);
356
357         tmp = ((block[6] & (3 << 6)) >> 6) | (block[0xb] << 2);
358         tmp *= 1000;
359         tmp += 512;
360         specs->chroma.bluex = tmp/1024;
361         DPRINTK("         BlueX:    0.%03d ", specs->chroma.bluex);
362
363         tmp = ((block[6] & (3 << 4)) >> 4) | (block[0xc] << 2);
364         tmp *= 1000;
365         tmp += 512;
366         specs->chroma.bluey = tmp/1024;
367         DPRINTK("BlueY:    0.%03d\n", specs->chroma.bluey);
368         
369         tmp = ((block[6] & (3 << 2)) >> 2) | (block[0xd] << 2);
370         tmp *= 1000;
371         tmp += 512;
372         specs->chroma.whitex = tmp/1024;
373         DPRINTK("         WhiteX:   0.%03d ", specs->chroma.whitex);
374
375         tmp = (block[6] & 3) | (block[0xe] << 2);
376         tmp *= 1000;
377         tmp += 512;
378         specs->chroma.whitey = tmp/1024;
379         DPRINTK("WhiteY:   0.%03d\n", specs->chroma.whitey);
380 }
381
382 static void calc_mode_timings(int xres, int yres, int refresh,
383                               struct fb_videomode *mode)
384 {
385         struct fb_var_screeninfo *var;
386         
387         var = kzalloc(sizeof(struct fb_var_screeninfo), GFP_KERNEL);
388
389         if (var) {
390                 var->xres = xres;
391                 var->yres = yres;
392                 fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON,
393                             refresh, var, NULL);
394                 mode->xres = xres;
395                 mode->yres = yres;
396                 mode->pixclock = var->pixclock;
397                 mode->refresh = refresh;
398                 mode->left_margin = var->left_margin;
399                 mode->right_margin = var->right_margin;
400                 mode->upper_margin = var->upper_margin;
401                 mode->lower_margin = var->lower_margin;
402                 mode->hsync_len = var->hsync_len;
403                 mode->vsync_len = var->vsync_len;
404                 mode->vmode = 0;
405                 mode->sync = 0;
406                 kfree(var);
407         }
408 }
409
410 static int get_est_timing(unsigned char *block, struct fb_videomode *mode)
411 {
412         int num = 0;
413         unsigned char c;
414
415         c = block[0];
416         if (c&0x80) {
417                 calc_mode_timings(720, 400, 70, &mode[num]);
418                 mode[num++].flag = FB_MODE_IS_CALCULATED;
419                 DPRINTK("      720x400@70Hz\n");
420         }
421         if (c&0x40) {
422                 calc_mode_timings(720, 400, 88, &mode[num]);
423                 mode[num++].flag = FB_MODE_IS_CALCULATED;
424                 DPRINTK("      720x400@88Hz\n");
425         }
426         if (c&0x20) {
427                 mode[num++] = vesa_modes[3];
428                 DPRINTK("      640x480@60Hz\n");
429         }
430         if (c&0x10) {
431                 calc_mode_timings(640, 480, 67, &mode[num]);
432                 mode[num++].flag = FB_MODE_IS_CALCULATED;
433                 DPRINTK("      640x480@67Hz\n");
434         }
435         if (c&0x08) {
436                 mode[num++] = vesa_modes[4];
437                 DPRINTK("      640x480@72Hz\n");
438         }
439         if (c&0x04) {
440                 mode[num++] = vesa_modes[5];
441                 DPRINTK("      640x480@75Hz\n");
442         }
443         if (c&0x02) {
444                 mode[num++] = vesa_modes[7];
445                 DPRINTK("      800x600@56Hz\n");
446         }
447         if (c&0x01) {
448                 mode[num++] = vesa_modes[8];
449                 DPRINTK("      800x600@60Hz\n");
450         }
451
452         c = block[1];
453         if (c&0x80) {
454                 mode[num++] = vesa_modes[9];
455                 DPRINTK("      800x600@72Hz\n");
456         }
457         if (c&0x40) {
458                 mode[num++] = vesa_modes[10];
459                 DPRINTK("      800x600@75Hz\n");
460         }
461         if (c&0x20) {
462                 calc_mode_timings(832, 624, 75, &mode[num]);
463                 mode[num++].flag = FB_MODE_IS_CALCULATED;
464                 DPRINTK("      832x624@75Hz\n");
465         }
466         if (c&0x10) {
467                 mode[num++] = vesa_modes[12];
468                 DPRINTK("      1024x768@87Hz Interlaced\n");
469         }
470         if (c&0x08) {
471                 mode[num++] = vesa_modes[13];
472                 DPRINTK("      1024x768@60Hz\n");
473         }
474         if (c&0x04) {
475                 mode[num++] = vesa_modes[14];
476                 DPRINTK("      1024x768@70Hz\n");
477         }
478         if (c&0x02) {
479                 mode[num++] = vesa_modes[15];
480                 DPRINTK("      1024x768@75Hz\n");
481         }
482         if (c&0x01) {
483                 mode[num++] = vesa_modes[21];
484                 DPRINTK("      1280x1024@75Hz\n");
485         }
486         c = block[2];
487         if (c&0x80) {
488                 mode[num++] = vesa_modes[17];
489                 DPRINTK("      1152x870@75Hz\n");
490         }
491         DPRINTK("      Manufacturer's mask: %x\n",c&0x7F);
492         return num;
493 }
494
495 static int get_std_timing(unsigned char *block, struct fb_videomode *mode)
496 {
497         int xres, yres = 0, refresh, ratio, i;
498         
499         xres = (block[0] + 31) * 8;
500         if (xres <= 256)
501                 return 0;
502
503         ratio = (block[1] & 0xc0) >> 6;
504         switch (ratio) {
505         case 0:
506                 yres = xres;
507                 break;
508         case 1:
509                 yres = (xres * 3)/4;
510                 break;
511         case 2:
512                 yres = (xres * 4)/5;
513                 break;
514         case 3:
515                 yres = (xres * 9)/16;
516                 break;
517         }
518         refresh = (block[1] & 0x3f) + 60;
519
520         DPRINTK("      %dx%d@%dHz\n", xres, yres, refresh);
521         for (i = 0; i < VESA_MODEDB_SIZE; i++) {
522                 if (vesa_modes[i].xres == xres && 
523                     vesa_modes[i].yres == yres &&
524                     vesa_modes[i].refresh == refresh) {
525                         *mode = vesa_modes[i];
526                         mode->flag |= FB_MODE_IS_STANDARD;
527                         return 1;
528                 }
529         }
530         calc_mode_timings(xres, yres, refresh, mode);
531         return 1;
532 }
533
534 static int get_dst_timing(unsigned char *block,
535                           struct fb_videomode *mode)
536 {
537         int j, num = 0;
538
539         for (j = 0; j < 6; j++, block+= STD_TIMING_DESCRIPTION_SIZE) 
540                 num += get_std_timing(block, &mode[num]);
541
542         return num;
543 }
544
545 static void get_detailed_timing(unsigned char *block, 
546                                 struct fb_videomode *mode)
547 {
548         mode->xres = H_ACTIVE;
549         mode->yres = V_ACTIVE;
550         mode->pixclock = PIXEL_CLOCK;
551         mode->pixclock /= 1000;
552         mode->pixclock = KHZ2PICOS(mode->pixclock);
553         mode->right_margin = H_SYNC_OFFSET;
554         mode->left_margin = (H_ACTIVE + H_BLANKING) -
555                 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
556         mode->upper_margin = V_BLANKING - V_SYNC_OFFSET - 
557                 V_SYNC_WIDTH;
558         mode->lower_margin = V_SYNC_OFFSET;
559         mode->hsync_len = H_SYNC_WIDTH;
560         mode->vsync_len = V_SYNC_WIDTH;
561         if (HSYNC_POSITIVE)
562                 mode->sync |= FB_SYNC_HOR_HIGH_ACT;
563         if (VSYNC_POSITIVE)
564                 mode->sync |= FB_SYNC_VERT_HIGH_ACT;
565         mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *
566                                      (V_ACTIVE + V_BLANKING));
567         mode->vmode = 0;
568         mode->flag = FB_MODE_IS_DETAILED;
569
570         DPRINTK("      %d MHz ",  PIXEL_CLOCK/1000000);
571         DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET,
572                H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING);
573         DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET,
574                V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING);
575         DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-",
576                (VSYNC_POSITIVE) ? "+" : "-");
577 }
578
579 /**
580  * fb_create_modedb - create video mode database
581  * @edid: EDID data
582  * @dbsize: database size
583  *
584  * RETURNS: struct fb_videomode, @dbsize contains length of database
585  *
586  * DESCRIPTION:
587  * This function builds a mode database using the contents of the EDID
588  * data
589  */
590 static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize)
591 {
592         struct fb_videomode *mode, *m;
593         unsigned char *block;
594         int num = 0, i, first = 1;
595
596         mode = kzalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
597         if (mode == NULL)
598                 return NULL;
599
600         if (edid == NULL || !edid_checksum(edid) || 
601             !edid_check_header(edid)) {
602                 kfree(mode);
603                 return NULL;
604         }
605
606         *dbsize = 0;
607
608         DPRINTK("   Detailed Timings\n");
609         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
610         for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
611                 if (!(block[0] == 0x00 && block[1] == 0x00)) {
612                         get_detailed_timing(block, &mode[num]);
613                         if (first) {
614                                 mode[num].flag |= FB_MODE_IS_FIRST;
615                                 first = 0;
616                         }
617                         num++;
618                 }
619         }
620
621         DPRINTK("   Supported VESA Modes\n");
622         block = edid + ESTABLISHED_TIMING_1;
623         num += get_est_timing(block, &mode[num]);
624
625         DPRINTK("   Standard Timings\n");
626         block = edid + STD_TIMING_DESCRIPTIONS_START;
627         for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE)
628                 num += get_std_timing(block, &mode[num]);
629
630         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
631         for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
632                 if (block[0] == 0x00 && block[1] == 0x00 && block[3] == 0xfa)
633                         num += get_dst_timing(block + 5, &mode[num]);
634         }
635         
636         /* Yikes, EDID data is totally useless */
637         if (!num) {
638                 kfree(mode);
639                 return NULL;
640         }
641
642         *dbsize = num;
643         m = kmalloc(num * sizeof(struct fb_videomode), GFP_KERNEL);
644         if (!m)
645                 return mode;
646         memmove(m, mode, num * sizeof(struct fb_videomode));
647         kfree(mode);
648         return m;
649 }
650
651 /**
652  * fb_destroy_modedb - destroys mode database
653  * @modedb: mode database to destroy
654  *
655  * DESCRIPTION:
656  * Destroy mode database created by fb_create_modedb
657  */
658 void fb_destroy_modedb(struct fb_videomode *modedb)
659 {
660         kfree(modedb);
661 }
662
663 static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
664 {
665         int i, retval = 1;
666         unsigned char *block;
667
668         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
669
670         DPRINTK("      Monitor Operating Limits: ");
671
672         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
673                 if (edid_is_limits_block(block)) {
674                         specs->hfmin = H_MIN_RATE * 1000;
675                         specs->hfmax = H_MAX_RATE * 1000;
676                         specs->vfmin = V_MIN_RATE;
677                         specs->vfmax = V_MAX_RATE;
678                         specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;
679                         specs->gtf = (GTF_SUPPORT) ? 1 : 0;
680                         retval = 0;
681                         DPRINTK("From EDID\n");
682                         break;
683                 }
684         }
685
686         /* estimate monitor limits based on modes supported */
687         if (retval) {
688                 struct fb_videomode *modes, *mode;
689                 int num_modes, i, hz, hscan, pixclock;
690                 int vtotal, htotal;
691
692                 modes = fb_create_modedb(edid, &num_modes);
693                 if (!modes) {
694                         DPRINTK("None Available\n");
695                         return 1;
696                 }
697
698                 retval = 0;
699                 for (i = 0; i < num_modes; i++) {
700                         mode = &modes[i];
701                         pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
702                         htotal = mode->xres + mode->right_margin + mode->hsync_len
703                                 + mode->left_margin;
704                         vtotal = mode->yres + mode->lower_margin + mode->vsync_len
705                                 + mode->upper_margin;
706
707                         if (mode->vmode & FB_VMODE_INTERLACED)
708                                 vtotal /= 2;
709
710                         if (mode->vmode & FB_VMODE_DOUBLE)
711                                 vtotal *= 2;
712
713                         hscan = (pixclock + htotal / 2) / htotal;
714                         hscan = (hscan + 500) / 1000 * 1000;
715                         hz = (hscan + vtotal / 2) / vtotal;
716                         
717                         if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
718                                 specs->dclkmax = pixclock;
719
720                         if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
721                                 specs->dclkmin = pixclock;
722
723                         if (specs->hfmax == 0 || specs->hfmax < hscan)
724                                 specs->hfmax = hscan;
725
726                         if (specs->hfmin == 0 || specs->hfmin > hscan)
727                                 specs->hfmin = hscan;
728
729                         if (specs->vfmax == 0 || specs->vfmax < hz)
730                                 specs->vfmax = hz;
731
732                         if (specs->vfmin == 0 || specs->vfmin > hz)
733                                 specs->vfmin = hz;
734                 }
735                 DPRINTK("Extrapolated\n");
736                 fb_destroy_modedb(modes);
737         }
738         DPRINTK("           H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",
739                 specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,
740                 specs->vfmax, specs->dclkmax/1000000);
741         return retval;
742 }
743
744 static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
745 {
746         unsigned char c, *block;
747
748         block = edid + EDID_STRUCT_DISPLAY;
749
750         fb_get_monitor_limits(edid, specs);
751
752         c = block[0] & 0x80;
753         specs->input = 0;
754         if (c) {
755                 specs->input |= FB_DISP_DDI;
756                 DPRINTK("      Digital Display Input");
757         } else {
758                 DPRINTK("      Analog Display Input: Input Voltage - ");
759                 switch ((block[0] & 0x60) >> 5) {
760                 case 0:
761                         DPRINTK("0.700V/0.300V");
762                         specs->input |= FB_DISP_ANA_700_300;
763                         break;
764                 case 1:
765                         DPRINTK("0.714V/0.286V");
766                         specs->input |= FB_DISP_ANA_714_286;
767                         break;
768                 case 2:
769                         DPRINTK("1.000V/0.400V");
770                         specs->input |= FB_DISP_ANA_1000_400;
771                         break;
772                 case 3:
773                         DPRINTK("0.700V/0.000V");
774                         specs->input |= FB_DISP_ANA_700_000;
775                         break;
776                 }
777         }
778         DPRINTK("\n      Sync: ");
779         c = block[0] & 0x10;
780         if (c)
781                 DPRINTK("      Configurable signal level\n");
782         c = block[0] & 0x0f;
783         specs->signal = 0;
784         if (c & 0x10) {
785                 DPRINTK("Blank to Blank ");
786                 specs->signal |= FB_SIGNAL_BLANK_BLANK;
787         }
788         if (c & 0x08) {
789                 DPRINTK("Separate ");
790                 specs->signal |= FB_SIGNAL_SEPARATE;
791         }
792         if (c & 0x04) {
793                 DPRINTK("Composite ");
794                 specs->signal |= FB_SIGNAL_COMPOSITE;
795         }
796         if (c & 0x02) {
797                 DPRINTK("Sync on Green ");
798                 specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
799         }
800         if (c & 0x01) {
801                 DPRINTK("Serration on ");
802                 specs->signal |= FB_SIGNAL_SERRATION_ON;
803         }
804         DPRINTK("\n");
805         specs->max_x = block[1];
806         specs->max_y = block[2];
807         DPRINTK("      Max H-size in cm: ");
808         if (specs->max_x)
809                 DPRINTK("%d\n", specs->max_x);
810         else
811                 DPRINTK("variable\n");
812         DPRINTK("      Max V-size in cm: ");
813         if (specs->max_y)
814                 DPRINTK("%d\n", specs->max_y);
815         else
816                 DPRINTK("variable\n");
817
818         c = block[3];
819         specs->gamma = c+100;
820         DPRINTK("      Gamma: ");
821         DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
822
823         get_dpms_capabilities(block[4], specs);
824
825         switch ((block[4] & 0x18) >> 3) {
826         case 0:
827                 DPRINTK("      Monochrome/Grayscale\n");
828                 specs->input |= FB_DISP_MONO;
829                 break;
830         case 1:
831                 DPRINTK("      RGB Color Display\n");
832                 specs->input |= FB_DISP_RGB;
833                 break;
834         case 2:
835                 DPRINTK("      Non-RGB Multicolor Display\n");
836                 specs->input |= FB_DISP_MULTI;
837                 break;
838         default:
839                 DPRINTK("      Unknown\n");
840                 specs->input |= FB_DISP_UNKNOWN;
841                 break;
842         }
843
844         get_chroma(block, specs);
845
846         specs->misc = 0;
847         c = block[4] & 0x7;
848         if (c & 0x04) {
849                 DPRINTK("      Default color format is primary\n");
850                 specs->misc |= FB_MISC_PRIM_COLOR;
851         }
852         if (c & 0x02) {
853                 DPRINTK("      First DETAILED Timing is preferred\n");
854                 specs->misc |= FB_MISC_1ST_DETAIL;
855         }
856         if (c & 0x01) {
857                 printk("      Display is GTF capable\n");
858                 specs->gtf = 1;
859         }
860 }
861
862 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
863 {
864         int i;
865         unsigned char *block;
866
867         if (edid == NULL || var == NULL)
868                 return 1;
869
870         if (!(edid_checksum(edid)))
871                 return 1;
872
873         if (!(edid_check_header(edid)))
874                 return 1;
875
876         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
877
878         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
879                 if (edid_is_timing_block(block)) {
880                         var->xres = var->xres_virtual = H_ACTIVE;
881                         var->yres = var->yres_virtual = V_ACTIVE;
882                         var->height = var->width = -1;
883                         var->right_margin = H_SYNC_OFFSET;
884                         var->left_margin = (H_ACTIVE + H_BLANKING) -
885                                 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
886                         var->upper_margin = V_BLANKING - V_SYNC_OFFSET -
887                                 V_SYNC_WIDTH;
888                         var->lower_margin = V_SYNC_OFFSET;
889                         var->hsync_len = H_SYNC_WIDTH;
890                         var->vsync_len = V_SYNC_WIDTH;
891                         var->pixclock = PIXEL_CLOCK;
892                         var->pixclock /= 1000;
893                         var->pixclock = KHZ2PICOS(var->pixclock);
894
895                         if (HSYNC_POSITIVE)
896                                 var->sync |= FB_SYNC_HOR_HIGH_ACT;
897                         if (VSYNC_POSITIVE)
898                                 var->sync |= FB_SYNC_VERT_HIGH_ACT;
899                         return 0;
900                 }
901         }
902         return 1;
903 }
904
905 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
906 {
907         unsigned char *block;
908         int i, found = 0;
909
910         if (edid == NULL)
911                 return;
912
913         if (!(edid_checksum(edid)))
914                 return;
915
916         if (!(edid_check_header(edid)))
917                 return;
918
919         memset(specs, 0, sizeof(struct fb_monspecs));
920
921         specs->version = edid[EDID_STRUCT_VERSION];
922         specs->revision = edid[EDID_STRUCT_REVISION];
923
924         DPRINTK("========================================\n");
925         DPRINTK("Display Information (EDID)\n");
926         DPRINTK("========================================\n");
927         DPRINTK("   EDID Version %d.%d\n", (int) specs->version,
928                (int) specs->revision);
929
930         parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);
931
932         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
933         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
934                 if (edid_is_serial_block(block)) {
935                         copy_string(block, specs->serial_no);
936                         DPRINTK("   Serial Number: %s\n", specs->serial_no);
937                 } else if (edid_is_ascii_block(block)) {
938                         copy_string(block, specs->ascii);
939                         DPRINTK("   ASCII Block: %s\n", specs->ascii);
940                 } else if (edid_is_monitor_block(block)) {
941                         copy_string(block, specs->monitor);
942                         DPRINTK("   Monitor Name: %s\n", specs->monitor);
943                 }
944         }
945
946         DPRINTK("   Display Characteristics:\n");
947         get_monspecs(edid, specs);
948
949         specs->modedb = fb_create_modedb(edid, &specs->modedb_len);
950
951         /*
952          * Workaround for buggy EDIDs that sets that the first
953          * detailed timing is preferred but has not detailed
954          * timing specified
955          */
956         for (i = 0; i < specs->modedb_len; i++) {
957                 if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {
958                         found = 1;
959                         break;
960                 }
961         }
962
963         if (!found)
964                 specs->misc &= ~FB_MISC_1ST_DETAIL;
965
966         DPRINTK("========================================\n");
967 }
968
969 /* 
970  * VESA Generalized Timing Formula (GTF) 
971  */
972
973 #define FLYBACK                     550
974 #define V_FRONTPORCH                1
975 #define H_OFFSET                    40
976 #define H_SCALEFACTOR               20
977 #define H_BLANKSCALE                128
978 #define H_GRADIENT                  600
979 #define C_VAL                       30
980 #define M_VAL                       300
981
982 struct __fb_timings {
983         u32 dclk;
984         u32 hfreq;
985         u32 vfreq;
986         u32 hactive;
987         u32 vactive;
988         u32 hblank;
989         u32 vblank;
990         u32 htotal;
991         u32 vtotal;
992 };
993
994 /**
995  * fb_get_vblank - get vertical blank time
996  * @hfreq: horizontal freq
997  *
998  * DESCRIPTION:
999  * vblank = right_margin + vsync_len + left_margin 
1000  *
1001  *    given: right_margin = 1 (V_FRONTPORCH)
1002  *           vsync_len    = 3
1003  *           flyback      = 550
1004  *
1005  *                          flyback * hfreq
1006  *           left_margin  = --------------- - vsync_len
1007  *                           1000000
1008  */
1009 static u32 fb_get_vblank(u32 hfreq)
1010 {
1011         u32 vblank;
1012
1013         vblank = (hfreq * FLYBACK)/1000; 
1014         vblank = (vblank + 500)/1000;
1015         return (vblank + V_FRONTPORCH);
1016 }
1017
1018 /** 
1019  * fb_get_hblank_by_freq - get horizontal blank time given hfreq
1020  * @hfreq: horizontal freq
1021  * @xres: horizontal resolution in pixels
1022  *
1023  * DESCRIPTION:
1024  *
1025  *           xres * duty_cycle
1026  * hblank = ------------------
1027  *           100 - duty_cycle
1028  *
1029  * duty cycle = percent of htotal assigned to inactive display
1030  * duty cycle = C - (M/Hfreq)
1031  *
1032  * where: C = ((offset - scale factor) * blank_scale)
1033  *            -------------------------------------- + scale factor
1034  *                        256 
1035  *        M = blank_scale * gradient
1036  *
1037  */
1038 static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
1039 {
1040         u32 c_val, m_val, duty_cycle, hblank;
1041
1042         c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 + 
1043                  H_SCALEFACTOR) * 1000;
1044         m_val = (H_BLANKSCALE * H_GRADIENT)/256;
1045         m_val = (m_val * 1000000)/hfreq;
1046         duty_cycle = c_val - m_val;
1047         hblank = (xres * duty_cycle)/(100000 - duty_cycle);
1048         return (hblank);
1049 }
1050
1051 /** 
1052  * fb_get_hblank_by_dclk - get horizontal blank time given pixelclock
1053  * @dclk: pixelclock in Hz
1054  * @xres: horizontal resolution in pixels
1055  *
1056  * DESCRIPTION:
1057  *
1058  *           xres * duty_cycle
1059  * hblank = ------------------
1060  *           100 - duty_cycle
1061  *
1062  * duty cycle = percent of htotal assigned to inactive display
1063  * duty cycle = C - (M * h_period)
1064  * 
1065  * where: h_period = SQRT(100 - C + (0.4 * xres * M)/dclk) + C - 100
1066  *                   -----------------------------------------------
1067  *                                    2 * M
1068  *        M = 300;
1069  *        C = 30;
1070
1071  */
1072 static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)
1073 {
1074         u32 duty_cycle, h_period, hblank;
1075
1076         dclk /= 1000;
1077         h_period = 100 - C_VAL;
1078         h_period *= h_period;
1079         h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);
1080         h_period *=10000; 
1081
1082         h_period = int_sqrt(h_period);
1083         h_period -= (100 - C_VAL) * 100;
1084         h_period *= 1000; 
1085         h_period /= 2 * M_VAL;
1086
1087         duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;
1088         hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;
1089         hblank &= ~15;
1090         return (hblank);
1091 }
1092         
1093 /**
1094  * fb_get_hfreq - estimate hsync
1095  * @vfreq: vertical refresh rate
1096  * @yres: vertical resolution
1097  *
1098  * DESCRIPTION:
1099  *
1100  *          (yres + front_port) * vfreq * 1000000
1101  * hfreq = -------------------------------------
1102  *          (1000000 - (vfreq * FLYBACK)
1103  * 
1104  */
1105
1106 static u32 fb_get_hfreq(u32 vfreq, u32 yres)
1107 {
1108         u32 divisor, hfreq;
1109         
1110         divisor = (1000000 - (vfreq * FLYBACK))/1000;
1111         hfreq = (yres + V_FRONTPORCH) * vfreq  * 1000;
1112         return (hfreq/divisor);
1113 }
1114
1115 static void fb_timings_vfreq(struct __fb_timings *timings)
1116 {
1117         timings->hfreq = fb_get_hfreq(timings->vfreq, timings->vactive);
1118         timings->vblank = fb_get_vblank(timings->hfreq);
1119         timings->vtotal = timings->vactive + timings->vblank;
1120         timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq, 
1121                                                  timings->hactive);
1122         timings->htotal = timings->hactive + timings->hblank;
1123         timings->dclk = timings->htotal * timings->hfreq;
1124 }
1125
1126 static void fb_timings_hfreq(struct __fb_timings *timings)
1127 {
1128         timings->vblank = fb_get_vblank(timings->hfreq);
1129         timings->vtotal = timings->vactive + timings->vblank;
1130         timings->vfreq = timings->hfreq/timings->vtotal;
1131         timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq, 
1132                                                  timings->hactive);
1133         timings->htotal = timings->hactive + timings->hblank;
1134         timings->dclk = timings->htotal * timings->hfreq;
1135 }
1136
1137 static void fb_timings_dclk(struct __fb_timings *timings)
1138 {
1139         timings->hblank = fb_get_hblank_by_dclk(timings->dclk, 
1140                                                 timings->hactive);
1141         timings->htotal = timings->hactive + timings->hblank;
1142         timings->hfreq = timings->dclk/timings->htotal;
1143         timings->vblank = fb_get_vblank(timings->hfreq);
1144         timings->vtotal = timings->vactive + timings->vblank;
1145         timings->vfreq = timings->hfreq/timings->vtotal;
1146 }
1147
1148 /*
1149  * fb_get_mode - calculates video mode using VESA GTF
1150  * @flags: if: 0 - maximize vertical refresh rate
1151  *             1 - vrefresh-driven calculation;
1152  *             2 - hscan-driven calculation;
1153  *             3 - pixelclock-driven calculation;
1154  * @val: depending on @flags, ignored, vrefresh, hsync or pixelclock
1155  * @var: pointer to fb_var_screeninfo
1156  * @info: pointer to fb_info
1157  *
1158  * DESCRIPTION:
1159  * Calculates video mode based on monitor specs using VESA GTF. 
1160  * The GTF is best for VESA GTF compliant monitors but is 
1161  * specifically formulated to work for older monitors as well.
1162  *
1163  * If @flag==0, the function will attempt to maximize the 
1164  * refresh rate.  Otherwise, it will calculate timings based on
1165  * the flag and accompanying value.  
1166  *
1167  * If FB_IGNOREMON bit is set in @flags, monitor specs will be 
1168  * ignored and @var will be filled with the calculated timings.
1169  *
1170  * All calculations are based on the VESA GTF Spreadsheet
1171  * available at VESA's public ftp (http://www.vesa.org).
1172  * 
1173  * NOTES:
1174  * The timings generated by the GTF will be different from VESA
1175  * DMT.  It might be a good idea to keep a table of standard
1176  * VESA modes as well.  The GTF may also not work for some displays,
1177  * such as, and especially, analog TV.
1178  *   
1179  * REQUIRES:
1180  * A valid info->monspecs, otherwise 'safe numbers' will be used.
1181  */ 
1182 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)
1183 {
1184         struct __fb_timings *timings;
1185         u32 interlace = 1, dscan = 1;
1186         u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;
1187
1188
1189         timings = kzalloc(sizeof(struct __fb_timings), GFP_KERNEL);
1190
1191         if (!timings)
1192                 return -ENOMEM;
1193
1194         /* 
1195          * If monspecs are invalid, use values that are enough
1196          * for 640x480@60
1197          */
1198         if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||
1199             !info->monspecs.dclkmax ||
1200             info->monspecs.hfmax < info->monspecs.hfmin ||
1201             info->monspecs.vfmax < info->monspecs.vfmin ||
1202             info->monspecs.dclkmax < info->monspecs.dclkmin) {
1203                 hfmin = 29000; hfmax = 30000;
1204                 vfmin = 60; vfmax = 60;
1205                 dclkmin = 0; dclkmax = 25000000;
1206         } else {
1207                 hfmin = info->monspecs.hfmin;
1208                 hfmax = info->monspecs.hfmax;
1209                 vfmin = info->monspecs.vfmin;
1210                 vfmax = info->monspecs.vfmax;
1211                 dclkmin = info->monspecs.dclkmin;
1212                 dclkmax = info->monspecs.dclkmax;
1213         }
1214
1215         timings->hactive = var->xres;
1216         timings->vactive = var->yres;
1217         if (var->vmode & FB_VMODE_INTERLACED) { 
1218                 timings->vactive /= 2;
1219                 interlace = 2;
1220         }
1221         if (var->vmode & FB_VMODE_DOUBLE) {
1222                 timings->vactive *= 2;
1223                 dscan = 2;
1224         }
1225
1226         switch (flags & ~FB_IGNOREMON) {
1227         case FB_MAXTIMINGS: /* maximize refresh rate */
1228                 timings->hfreq = hfmax;
1229                 fb_timings_hfreq(timings);
1230                 if (timings->vfreq > vfmax) {
1231                         timings->vfreq = vfmax;
1232                         fb_timings_vfreq(timings);
1233                 }
1234                 if (timings->dclk > dclkmax) {
1235                         timings->dclk = dclkmax;
1236                         fb_timings_dclk(timings);
1237                 }
1238                 break;
1239         case FB_VSYNCTIMINGS: /* vrefresh driven */
1240                 timings->vfreq = val;
1241                 fb_timings_vfreq(timings);
1242                 break;
1243         case FB_HSYNCTIMINGS: /* hsync driven */
1244                 timings->hfreq = val;
1245                 fb_timings_hfreq(timings);
1246                 break;
1247         case FB_DCLKTIMINGS: /* pixelclock driven */
1248                 timings->dclk = PICOS2KHZ(val) * 1000;
1249                 fb_timings_dclk(timings);
1250                 break;
1251         default:
1252                 err = -EINVAL;
1253                 
1254         } 
1255         
1256         if (err || (!(flags & FB_IGNOREMON) &&
1257             (timings->vfreq < vfmin || timings->vfreq > vfmax ||
1258              timings->hfreq < hfmin || timings->hfreq > hfmax ||
1259              timings->dclk < dclkmin || timings->dclk > dclkmax))) {
1260                 err = -EINVAL;
1261         } else {
1262                 var->pixclock = KHZ2PICOS(timings->dclk/1000);
1263                 var->hsync_len = (timings->htotal * 8)/100;
1264                 var->right_margin = (timings->hblank/2) - var->hsync_len;
1265                 var->left_margin = timings->hblank - var->right_margin -
1266                         var->hsync_len;
1267                 var->vsync_len = (3 * interlace)/dscan;
1268                 var->lower_margin = (1 * interlace)/dscan;
1269                 var->upper_margin = (timings->vblank * interlace)/dscan -
1270                         (var->vsync_len + var->lower_margin);
1271         }
1272         
1273         kfree(timings);
1274         return err;
1275 }
1276 #else
1277 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
1278 {
1279         return 1;
1280 }
1281 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1282 {
1283         specs = NULL;
1284 }
1285 void fb_destroy_modedb(struct fb_videomode *modedb)
1286 {
1287 }
1288 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
1289                 struct fb_info *info)
1290 {
1291         return -EINVAL;
1292 }
1293 #endif /* CONFIG_FB_MODE_HELPERS */
1294         
1295 /*
1296  * fb_validate_mode - validates var against monitor capabilities
1297  * @var: pointer to fb_var_screeninfo
1298  * @info: pointer to fb_info
1299  *
1300  * DESCRIPTION:
1301  * Validates video mode against monitor capabilities specified in
1302  * info->monspecs.
1303  *
1304  * REQUIRES:
1305  * A valid info->monspecs.
1306  */
1307 int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
1308 {
1309         u32 hfreq, vfreq, htotal, vtotal, pixclock;
1310         u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
1311
1312         /* 
1313          * If monspecs are invalid, use values that are enough
1314          * for 640x480@60
1315          */
1316         if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
1317             !info->monspecs.dclkmax ||
1318             info->monspecs.hfmax < info->monspecs.hfmin ||
1319             info->monspecs.vfmax < info->monspecs.vfmin ||
1320             info->monspecs.dclkmax < info->monspecs.dclkmin) {
1321                 hfmin = 29000; hfmax = 30000;
1322                 vfmin = 60; vfmax = 60;
1323                 dclkmin = 0; dclkmax = 25000000;
1324         } else {
1325                 hfmin = info->monspecs.hfmin;
1326                 hfmax = info->monspecs.hfmax;
1327                 vfmin = info->monspecs.vfmin;
1328                 vfmax = info->monspecs.vfmax;
1329                 dclkmin = info->monspecs.dclkmin;
1330                 dclkmax = info->monspecs.dclkmax;
1331         }
1332
1333         if (!var->pixclock)
1334                 return -EINVAL;
1335         pixclock = PICOS2KHZ(var->pixclock) * 1000;
1336            
1337         htotal = var->xres + var->right_margin + var->hsync_len + 
1338                 var->left_margin;
1339         vtotal = var->yres + var->lower_margin + var->vsync_len + 
1340                 var->upper_margin;
1341
1342         if (var->vmode & FB_VMODE_INTERLACED)
1343                 vtotal /= 2;
1344         if (var->vmode & FB_VMODE_DOUBLE)
1345                 vtotal *= 2;
1346
1347         hfreq = pixclock/htotal;
1348         hfreq = (hfreq + 500) / 1000 * 1000;
1349
1350         vfreq = hfreq/vtotal;
1351
1352         return (vfreq < vfmin || vfreq > vfmax || 
1353                 hfreq < hfmin || hfreq > hfmax ||
1354                 pixclock < dclkmin || pixclock > dclkmax) ?
1355                 -EINVAL : 0;
1356 }
1357
1358 #if defined(CONFIG_FIRMWARE_EDID) && defined(CONFIG_X86)
1359
1360 /*
1361  * We need to ensure that the EDID block is only returned for
1362  * the primary graphics adapter.
1363  */
1364
1365 const unsigned char *fb_firmware_edid(struct device *device)
1366 {
1367         struct pci_dev *dev = NULL;
1368         struct resource *res = NULL;
1369         unsigned char *edid = NULL;
1370
1371         if (device)
1372                 dev = to_pci_dev(device);
1373
1374         if (dev)
1375                 res = &dev->resource[PCI_ROM_RESOURCE];
1376
1377         if (res && res->flags & IORESOURCE_ROM_SHADOW)
1378                 edid = edid_info.dummy;
1379
1380         return edid;
1381 }
1382 #else
1383 const unsigned char *fb_firmware_edid(struct device *device)
1384 {
1385         return NULL;
1386 }
1387 #endif
1388 EXPORT_SYMBOL(fb_firmware_edid);
1389
1390 EXPORT_SYMBOL(fb_parse_edid);
1391 EXPORT_SYMBOL(fb_edid_to_monspecs);
1392 EXPORT_SYMBOL(fb_get_mode);
1393 EXPORT_SYMBOL(fb_validate_mode);
1394 EXPORT_SYMBOL(fb_destroy_modedb);