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/tty.h>
  30 #include <linux/fb.h>
  31 #include <linux/module.h>
  32 #include <video/edid.h>
  33 #ifdef CONFIG_PPC_OF
  34 #include <linux/pci.h>
  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
  55 #ifdef CONFIG_FB_MODE_HELPERS
  56 struct broken_edid {
  57         u8  manufacturer[4];
  58         u32 model;
  59         u32 fix;
  60 };
  61
  62 static 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 };
  76
  77 static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
  78         0xff, 0xff, 0xff, 0x00
  79 };
  80
  81 static void copy_string(unsigned char *c, unsigned char *s)
  82 {
  83   int i;
  84   c = c + 5;
  85   for (i = 0; (i < 13 && *c != 0x0A); i++)
  86     *(s++) = *(c++);
  87   *s = 0;
  88   while (i-- && (*--s == 0x20)) *s = 0;
  89 }
  90
  91 static int check_edid(unsigned char *edid)
  92 {
  93         unsigned char *block = edid + ID_MANUFACTURER_NAME, manufacturer[4];
  94         unsigned char *b;
  95         u32 model;
  96         int i, fix = 0, ret = 0;
  97
  98         manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
  99         manufacturer[1] = ((block[0] & 0x03) << 3) +
 100                 ((block[1] & 0xe0) >> 5) + '@';
 101         manufacturer[2] = (block[1] & 0x1f) + '@';
 102         manufacturer[3] = 0;
 103         model = block[2] + (block[3] << 8);
 104
 105         for (i = 0; i < ARRAY_SIZE(brokendb); i++) {
 106                 if (!strncmp(manufacturer, brokendb[i].manufacturer, 4) &&
 107                         brokendb[i].model == model) {
 108                         printk("fbmon: The EDID Block of "
 109                                "Manufacturer: %s Model: 0x%x is known to "
 110                                "be broken,\n",  manufacturer, model);
 111                         fix = brokendb[i].fix;
 112                         break;
 113                 }
 114         }
 115
 116         switch (fix) {
 117         case FBMON_FIX_HEADER:
 118                 for (i = 0; i < 8; i++) {
 119                         if (edid[i] != edid_v1_header[i])
 120                                 ret = fix;
 121                 }
 122                 break;
 123         case FBMON_FIX_INPUT:
 124                 b = edid + EDID_STRUCT_DISPLAY;
 125                 /* Only if display is GTF capable will
 126                    the input type be reset to analog */
 127                 if (b[4] & 0x01 && b[0] & 0x80)
 128                         ret = fix;
 129                 break;
 130         }
 131
 132         return ret;
 133 }
 134
 135 static void fix_edid(unsigned char *edid, int fix)
 136 {
 137         unsigned char *b;
 138
 139         switch (fix) {
 140         case FBMON_FIX_HEADER:
 141                 printk("fbmon: trying a header reconstruct\n");
 142                 memcpy(edid, edid_v1_header, 8);
 143                 break;
 144         case FBMON_FIX_INPUT:
 145                 printk("fbmon: trying to fix input type\n");
 146                 b = edid + EDID_STRUCT_DISPLAY;
 147                 b[0] &= ~0x80;
 148                 edid[127] += 0x80;
 149         }
 150 }
 151
 152 static int edid_checksum(unsigned char *edid)
 153 {
 154         unsigned char i, csum = 0, all_null = 0;
 155         int err = 0, fix = check_edid(edid);
 156
 157         if (fix)
 158                 fix_edid(edid, fix);
 159
 160         for (i = 0; i < EDID_LENGTH; i++) {
 161                 csum += edid[i];
 162                 all_null |= edid[i];
 163         }
 164
 165         if (csum == 0x00 && all_null) {
 166                 /* checksum passed, everything's good */
 167                 err = 1;
 168         }
 169
 170         return err;
 171 }
 172
 173 static int edid_check_header(unsigned char *edid)
 174 {
 175         int i, err = 1, fix = check_edid(edid);
 176
 177         if (fix)
 178                 fix_edid(edid, fix);
 179
 180         for (i = 0; i < 8; i++) {
 181                 if (edid[i] != edid_v1_header[i])
 182                         err = 0;
 183         }
 184
 185         return err;
 186 }
 187
 188 static void parse_vendor_block(unsigned char *block, struct fb_monspecs *specs)
 189 {
 190         specs->manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
 191         specs->manufacturer[1] = ((block[0] & 0x03) << 3) +
 192                 ((block[1] & 0xe0) >> 5) + '@';
 193         specs->manufacturer[2] = (block[1] & 0x1f) + '@';
 194         specs->manufacturer[3] = 0;
 195         specs->model = block[2] + (block[3] << 8);
 196         specs->serial = block[4] + (block[5] << 8) +
 197                (block[6] << 16) + (block[7] << 24);
 198         specs->year = block[9] + 1990;
 199         specs->week = block[8];
 200         DPRINTK("   Manufacturer: %s\n", specs->manufacturer);
 201         DPRINTK("   Model: %x\n", specs->model);
 202         DPRINTK("   Serial#: %u\n", specs->serial);
 203         DPRINTK("   Year: %u Week %u\n", specs->year, specs->week);
 204 }
 205
 206 static void get_dpms_capabilities(unsigned char flags,
 207                                   struct fb_monspecs *specs)
 208 {
 209         specs->dpms = 0;
 210         if (flags & DPMS_ACTIVE_OFF)
 211                 specs->dpms |= FB_DPMS_ACTIVE_OFF;
 212         if (flags & DPMS_SUSPEND)
 213                 specs->dpms |= FB_DPMS_SUSPEND;
 214         if (flags & DPMS_STANDBY)
 215                 specs->dpms |= FB_DPMS_STANDBY;
 216         DPRINTK("      DPMS: Active %s, Suspend %s, Standby %s\n",
 217                (flags & DPMS_ACTIVE_OFF) ? "yes" : "no",
 218                (flags & DPMS_SUSPEND)    ? "yes" : "no",
 219                (flags & DPMS_STANDBY)    ? "yes" : "no");
 220 }
 221
 222 static void get_chroma(unsigned char *block, struct fb_monspecs *specs)
 223 {
 224         int tmp;
 225
 226         DPRINTK("      Chroma\n");
 227         /* Chromaticity data */
 228         tmp = ((block[5] & (3 << 6)) >> 6) | (block[0x7] << 2);
 229         tmp *= 1000;
 230         tmp += 512;
 231         specs->chroma.redx = tmp/1024;
 232         DPRINTK("         RedX:     0.%03d ", specs->chroma.redx);
 233
 234         tmp = ((block[5] & (3 << 4)) >> 4) | (block[0x8] << 2);
 235         tmp *= 1000;
 236         tmp += 512;
 237         specs->chroma.redy = tmp/1024;
 238         DPRINTK("RedY:     0.%03d\n", specs->chroma.redy);
 239
 240         tmp = ((block[5] & (3 << 2)) >> 2) | (block[0x9] << 2);
 241         tmp *= 1000;
 242         tmp += 512;
 243         specs->chroma.greenx = tmp/1024;
 244         DPRINTK("         GreenX:   0.%03d ", specs->chroma.greenx);
 245
 246         tmp = (block[5] & 3) | (block[0xa] << 2);
 247         tmp *= 1000;
 248         tmp += 512;
 249         specs->chroma.greeny = tmp/1024;
 250         DPRINTK("GreenY:   0.%03d\n", specs->chroma.greeny);
 251
 252         tmp = ((block[6] & (3 << 6)) >> 6) | (block[0xb] << 2);
 253         tmp *= 1000;
 254         tmp += 512;
 255         specs->chroma.bluex = tmp/1024;
 256         DPRINTK("         BlueX:    0.%03d ", specs->chroma.bluex);
 257
 258         tmp = ((block[6] & (3 << 4)) >> 4) | (block[0xc] << 2);
 259         tmp *= 1000;
 260         tmp += 512;
 261         specs->chroma.bluey = tmp/1024;
 262         DPRINTK("BlueY:    0.%03d\n", specs->chroma.bluey);
 263
 264         tmp = ((block[6] & (3 << 2)) >> 2) | (block[0xd] << 2);
 265         tmp *= 1000;
 266         tmp += 512;
 267         specs->chroma.whitex = tmp/1024;
 268         DPRINTK("         WhiteX:   0.%03d ", specs->chroma.whitex);
 269
 270         tmp = (block[6] & 3) | (block[0xe] << 2);
 271         tmp *= 1000;
 272         tmp += 512;
 273         specs->chroma.whitey = tmp/1024;
 274         DPRINTK("WhiteY:   0.%03d\n", specs->chroma.whitey);
 275 }
 276
 277 static int edid_is_serial_block(unsigned char *block)
 278 {
 279         if ((block[0] == 0x00) && (block[1] == 0x00) &&
 280             (block[2] == 0x00) && (block[3] == 0xff) &&
 281             (block[4] == 0x00))
 282                 return 1;
 283         else
 284                 return 0;
 285 }
 286
 287 static int edid_is_ascii_block(unsigned char *block)
 288 {
 289         if ((block[0] == 0x00) && (block[1] == 0x00) &&
 290             (block[2] == 0x00) && (block[3] == 0xfe) &&
 291             (block[4] == 0x00))
 292                 return 1;
 293         else
 294                 return 0;
 295 }
 296
 297 static int edid_is_limits_block(unsigned char *block)
 298 {
 299         if ((block[0] == 0x00) && (block[1] == 0x00) &&
 300             (block[2] == 0x00) && (block[3] == 0xfd) &&
 301             (block[4] == 0x00))
 302                 return 1;
 303         else
 304                 return 0;
 305 }
 306
 307 static int edid_is_monitor_block(unsigned char *block)
 308 {
 309         if ((block[0] == 0x00) && (block[1] == 0x00) &&
 310             (block[2] == 0x00) && (block[3] == 0xfc) &&
 311             (block[4] == 0x00))
 312                 return 1;
 313         else
 314                 return 0;
 315 }
 316
 317 static void calc_mode_timings(int xres, int yres, int refresh,
 318                               struct fb_videomode *mode)
 319 {
 320         struct fb_var_screeninfo *var;
 321
 322         var = kzalloc(sizeof(struct fb_var_screeninfo), GFP_KERNEL);
 323
 324         if (var) {
 325                 var->xres = xres;
 326                 var->yres = yres;
 327                 fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON,
 328                             refresh, var, NULL);
 329                 mode->xres = xres;
 330                 mode->yres = yres;
 331                 mode->pixclock = var->pixclock;
 332                 mode->refresh = refresh;
 333                 mode->left_margin = var->left_margin;
 334                 mode->right_margin = var->right_margin;
 335                 mode->upper_margin = var->upper_margin;
 336                 mode->lower_margin = var->lower_margin;
 337                 mode->hsync_len = var->hsync_len;
 338                 mode->vsync_len = var->vsync_len;
 339                 mode->vmode = 0;
 340                 mode->sync = 0;
 341                 kfree(var);
 342         }
 343 }
 344
 345 static int get_est_timing(unsigned char *block, struct fb_videomode *mode)
 346 {
 347         int num = 0;
 348         unsigned char c;
 349
 350         c = block[0];
 351         if (c&0x80) {
 352                 calc_mode_timings(720, 400, 70, &mode[num]);
 353                 mode[num++].flag = FB_MODE_IS_CALCULATED;
 354                 DPRINTK("      720x400@70Hz\n");
 355         }
 356         if (c&0x40) {
 357                 calc_mode_timings(720, 400, 88, &mode[num]);
 358                 mode[num++].flag = FB_MODE_IS_CALCULATED;
 359                 DPRINTK("      720x400@88Hz\n");
 360         }
 361         if (c&0x20) {
 362                 mode[num++] = vesa_modes[3];
 363                 DPRINTK("      640x480@60Hz\n");
 364         }
 365         if (c&0x10) {
 366                 calc_mode_timings(640, 480, 67, &mode[num]);
 367                 mode[num++].flag = FB_MODE_IS_CALCULATED;
 368                 DPRINTK("      640x480@67Hz\n");
 369         }
 370         if (c&0x08) {
 371                 mode[num++] = vesa_modes[4];
 372                 DPRINTK("      640x480@72Hz\n");
 373         }
 374         if (c&0x04) {
 375                 mode[num++] = vesa_modes[5];
 376                 DPRINTK("      640x480@75Hz\n");
 377         }
 378         if (c&0x02) {
 379                 mode[num++] = vesa_modes[7];
 380                 DPRINTK("      800x600@56Hz\n");
 381         }
 382         if (c&0x01) {
 383                 mode[num++] = vesa_modes[8];
 384                 DPRINTK("      800x600@60Hz\n");
 385         }
 386
 387         c = block[1];
 388         if (c&0x80) {
 389                 mode[num++] = vesa_modes[9];
 390                 DPRINTK("      800x600@72Hz\n");
 391         }
 392         if (c&0x40) {
 393                 mode[num++] = vesa_modes[10];
 394                 DPRINTK("      800x600@75Hz\n");
 395         }
 396         if (c&0x20) {
 397                 calc_mode_timings(832, 624, 75, &mode[num]);
 398                 mode[num++].flag = FB_MODE_IS_CALCULATED;
 399                 DPRINTK("      832x624@75Hz\n");
 400         }
 401         if (c&0x10) {
 402                 mode[num++] = vesa_modes[12];
 403                 DPRINTK("      1024x768@87Hz Interlaced\n");
 404         }
 405         if (c&0x08) {
 406                 mode[num++] = vesa_modes[13];
 407                 DPRINTK("      1024x768@60Hz\n");
 408         }
 409         if (c&0x04) {
 410                 mode[num++] = vesa_modes[14];
 411                 DPRINTK("      1024x768@70Hz\n");
 412         }
 413         if (c&0x02) {
 414                 mode[num++] = vesa_modes[15];
 415                 DPRINTK("      1024x768@75Hz\n");
 416         }
 417         if (c&0x01) {
 418                 mode[num++] = vesa_modes[21];
 419                 DPRINTK("      1280x1024@75Hz\n");
 420         }
 421         c = block[2];
 422         if (c&0x80) {
 423                 mode[num++] = vesa_modes[17];
 424                 DPRINTK("      1152x870@75Hz\n");
 425         }
 426         DPRINTK("      Manufacturer's mask: %x\n",c&0x7F);
 427         return num;
 428 }
 429
 430 static int get_std_timing(unsigned char *block, struct fb_videomode *mode)
 431 {
 432         int xres, yres = 0, refresh, ratio, i;
 433
 434         xres = (block[0] + 31) * 8;
 435         if (xres <= 256)
 436                 return 0;
 437
 438         ratio = (block[1] & 0xc0) >> 6;
 439         switch (ratio) {
 440         case 0:
 441                 yres = xres;
 442                 break;
 443         case 1:
 444                 yres = (xres * 3)/4;
 445                 break;
 446         case 2:
 447                 yres = (xres * 4)/5;
 448                 break;
 449         case 3:
 450                 yres = (xres * 9)/16;
 451                 break;
 452         }
 453         refresh = (block[1] & 0x3f) + 60;
 454
 455         DPRINTK("      %dx%d@%dHz\n", xres, yres, refresh);
 456         for (i = 0; i < VESA_MODEDB_SIZE; i++) {
 457                 if (vesa_modes[i].xres == xres &&
 458                     vesa_modes[i].yres == yres &&
 459                     vesa_modes[i].refresh == refresh) {
 460                         *mode = vesa_modes[i];
 461                         mode->flag |= FB_MODE_IS_STANDARD;
 462                         return 1;
 463                 }
 464         }
 465         calc_mode_timings(xres, yres, refresh, mode);
 466         return 1;
 467 }
 468
 469 static int get_dst_timing(unsigned char *block,
 470                           struct fb_videomode *mode)
 471 {
 472         int j, num = 0;
 473
 474         for (j = 0; j < 6; j++, block+= STD_TIMING_DESCRIPTION_SIZE)
 475                 num += get_std_timing(block, &mode[num]);
 476
 477         return num;
 478 }
 479
 480 static void get_detailed_timing(unsigned char *block,
 481                                 struct fb_videomode *mode)
 482 {
 483         mode->xres = H_ACTIVE;
 484         mode->yres = V_ACTIVE;
 485         mode->pixclock = PIXEL_CLOCK;
 486         mode->pixclock /= 1000;
 487         mode->pixclock = KHZ2PICOS(mode->pixclock);
 488         mode->right_margin = H_SYNC_OFFSET;
 489         mode->left_margin = (H_ACTIVE + H_BLANKING) -
 490                 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
 491         mode->upper_margin = V_BLANKING - V_SYNC_OFFSET -
 492                 V_SYNC_WIDTH;
 493         mode->lower_margin = V_SYNC_OFFSET;
 494         mode->hsync_len = H_SYNC_WIDTH;
 495         mode->vsync_len = V_SYNC_WIDTH;
 496         if (HSYNC_POSITIVE)
 497                 mode->sync |= FB_SYNC_HOR_HIGH_ACT;
 498         if (VSYNC_POSITIVE)
 499                 mode->sync |= FB_SYNC_VERT_HIGH_ACT;
 500         mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *
 501                                      (V_ACTIVE + V_BLANKING));
 502         mode->vmode = 0;
 503         mode->flag = FB_MODE_IS_DETAILED;
 504
 505         DPRINTK("      %d MHz ",  PIXEL_CLOCK/1000000);
 506         DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET,
 507                H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING);
 508         DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET,
 509                V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING);
 510         DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-",
 511                (VSYNC_POSITIVE) ? "+" : "-");
 512 }
 513
 514 /**
 515  * fb_create_modedb - create video mode database
 516  * @edid: EDID data
 517  * @dbsize: database size
 518  *
 519  * RETURNS: struct fb_videomode, @dbsize contains length of database
 520  *
 521  * DESCRIPTION:
 522  * This function builds a mode database using the contents of the EDID
 523  * data
 524  */
 525 static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize)
 526 {
 527         struct fb_videomode *mode, *m;
 528         unsigned char *block;
 529         int num = 0, i;
 530
 531         mode = kzalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
 532         if (mode == NULL)
 533                 return NULL;
 534
 535         if (edid == NULL || !edid_checksum(edid) ||
 536             !edid_check_header(edid)) {
 537                 kfree(mode);
 538                 return NULL;
 539         }
 540
 541         *dbsize = 0;
 542
 543         DPRINTK("   Detailed Timings\n");
 544         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 545         for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
 546                 int first = 1;
 547
 548                 if (!(block[0] == 0x00 && block[1] == 0x00)) {
 549                         get_detailed_timing(block, &mode[num]);
 550                         if (first) {
 551                                 mode[num].flag |= FB_MODE_IS_FIRST;
 552                                 first = 0;
 553                         }
 554                         num++;
 555                 }
 556         }
 557
 558         DPRINTK("   Supported VESA Modes\n");
 559         block = edid + ESTABLISHED_TIMING_1;
 560         num += get_est_timing(block, &mode[num]);
 561
 562         DPRINTK("   Standard Timings\n");
 563         block = edid + STD_TIMING_DESCRIPTIONS_START;
 564         for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE)
 565                 num += get_std_timing(block, &mode[num]);
 566
 567         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 568         for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
 569                 if (block[0] == 0x00 && block[1] == 0x00 && block[3] == 0xfa)
 570                         num += get_dst_timing(block + 5, &mode[num]);
 571         }
 572
 573         /* Yikes, EDID data is totally useless */
 574         if (!num) {
 575                 kfree(mode);
 576                 return NULL;
 577         }
 578
 579         *dbsize = num;
 580         m = kmalloc(num * sizeof(struct fb_videomode), GFP_KERNEL);
 581         if (!m)
 582                 return mode;
 583         memmove(m, mode, num * sizeof(struct fb_videomode));
 584         kfree(mode);
 585         return m;
 586 }
 587
 588 /**
 589  * fb_destroy_modedb - destroys mode database
 590  * @modedb: mode database to destroy
 591  *
 592  * DESCRIPTION:
 593  * Destroy mode database created by fb_create_modedb
 594  */
 595 void fb_destroy_modedb(struct fb_videomode *modedb)
 596 {
 597         kfree(modedb);
 598 }
 599
 600 static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
 601 {
 602         int i, retval = 1;
 603         unsigned char *block;
 604
 605         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 606
 607         DPRINTK("      Monitor Operating Limits: ");
 608         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
 609                 if (edid_is_limits_block(block)) {
 610                         specs->hfmin = H_MIN_RATE * 1000;
 611                         specs->hfmax = H_MAX_RATE * 1000;
 612                         specs->vfmin = V_MIN_RATE;
 613                         specs->vfmax = V_MAX_RATE;
 614                         specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;
 615                         specs->gtf = (GTF_SUPPORT) ? 1 : 0;
 616                         retval = 0;
 617                         DPRINTK("From EDID\n");
 618                         break;
 619                 }
 620         }
 621
 622         /* estimate monitor limits based on modes supported */
 623         if (retval) {
 624                 struct fb_videomode *modes;
 625                 int num_modes, i, hz, hscan, pixclock;
 626
 627                 modes = fb_create_modedb(edid, &num_modes);
 628                 if (!modes) {
 629                         DPRINTK("None Available\n");
 630                         return 1;
 631                 }
 632
 633                 retval = 0;
 634                 for (i = 0; i < num_modes; i++) {
 635                         hz = modes[i].refresh;
 636                         pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
 637                         hscan = (modes[i].yres * 105 * hz + 5000)/100;
 638
 639                         if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
 640                                 specs->dclkmax = pixclock;
 641                         if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
 642                                 specs->dclkmin = pixclock;
 643                         if (specs->hfmax == 0 || specs->hfmax < hscan)
 644                                 specs->hfmax = hscan;
 645                         if (specs->hfmin == 0 || specs->hfmin > hscan)
 646                                 specs->hfmin = hscan;
 647                         if (specs->vfmax == 0 || specs->vfmax < hz)
 648                                 specs->vfmax = hz;
 649                         if (specs->vfmin == 0 || specs->vfmin > hz)
 650                                 specs->vfmin = hz;
 651                 }
 652                 DPRINTK("Extrapolated\n");
 653                 fb_destroy_modedb(modes);
 654         }
 655         DPRINTK("           H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",
 656                 specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,
 657                 specs->vfmax, specs->dclkmax/1000000);
 658         return retval;
 659 }
 660
 661 static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
 662 {
 663         unsigned char c, *block;
 664
 665         block = edid + EDID_STRUCT_DISPLAY;
 666
 667         fb_get_monitor_limits(edid, specs);
 668
 669         c = block[0] & 0x80;
 670         specs->input = 0;
 671         if (c) {
 672                 specs->input |= FB_DISP_DDI;
 673                 DPRINTK("      Digital Display Input");
 674         } else {
 675                 DPRINTK("      Analog Display Input: Input Voltage - ");
 676                 switch ((block[0] & 0x60) >> 5) {
 677                 case 0:
 678                         DPRINTK("0.700V/0.300V");
 679                         specs->input |= FB_DISP_ANA_700_300;
 680                         break;
 681                 case 1:
 682                         DPRINTK("0.714V/0.286V");
 683                         specs->input |= FB_DISP_ANA_714_286;
 684                         break;
 685                 case 2:
 686                         DPRINTK("1.000V/0.400V");
 687                         specs->input |= FB_DISP_ANA_1000_400;
 688                         break;
 689                 case 3:
 690                         DPRINTK("0.700V/0.000V");
 691                         specs->input |= FB_DISP_ANA_700_000;
 692                         break;
 693                 }
 694         }
 695         DPRINTK("\n      Sync: ");
 696         c = block[0] & 0x10;
 697         if (c)
 698                 DPRINTK("      Configurable signal level\n");
 699         c = block[0] & 0x0f;
 700         specs->signal = 0;
 701         if (c & 0x10) {
 702                 DPRINTK("Blank to Blank ");
 703                 specs->signal |= FB_SIGNAL_BLANK_BLANK;
 704         }
 705         if (c & 0x08) {
 706                 DPRINTK("Separate ");
 707                 specs->signal |= FB_SIGNAL_SEPARATE;
 708         }
 709         if (c & 0x04) {
 710                 DPRINTK("Composite ");
 711                 specs->signal |= FB_SIGNAL_COMPOSITE;
 712         }
 713         if (c & 0x02) {
 714                 DPRINTK("Sync on Green ");
 715                 specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
 716         }
 717         if (c & 0x01) {
 718                 DPRINTK("Serration on ");
 719                 specs->signal |= FB_SIGNAL_SERRATION_ON;
 720         }
 721         DPRINTK("\n");
 722         specs->max_x = block[1];
 723         specs->max_y = block[2];
 724         DPRINTK("      Max H-size in cm: ");
 725         if (specs->max_x)
 726                 DPRINTK("%d\n", specs->max_x);
 727         else
 728                 DPRINTK("variable\n");
 729         DPRINTK("      Max V-size in cm: ");
 730         if (specs->max_y)
 731                 DPRINTK("%d\n", specs->max_y);
 732         else
 733                 DPRINTK("variable\n");
 734
 735         c = block[3];
 736         specs->gamma = c+100;
 737         DPRINTK("      Gamma: ");
 738         DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
 739
 740         get_dpms_capabilities(block[4], specs);
 741
 742         switch ((block[4] & 0x18) >> 3) {
 743         case 0:
 744                 DPRINTK("      Monochrome/Grayscale\n");
 745                 specs->input |= FB_DISP_MONO;
 746                 break;
 747         case 1:
 748                 DPRINTK("      RGB Color Display\n");
 749                 specs->input |= FB_DISP_RGB;
 750                 break;
 751         case 2:
 752                 DPRINTK("      Non-RGB Multicolor Display\n");
 753                 specs->input |= FB_DISP_MULTI;
 754                 break;
 755         default:
 756                 DPRINTK("      Unknown\n");
 757                 specs->input |= FB_DISP_UNKNOWN;
 758                 break;
 759         }
 760
 761         get_chroma(block, specs);
 762
 763         specs->misc = 0;
 764         c = block[4] & 0x7;
 765         if (c & 0x04) {
 766                 DPRINTK("      Default color format is primary\n");
 767                 specs->misc |= FB_MISC_PRIM_COLOR;
 768         }
 769         if (c & 0x02) {
 770                 DPRINTK("      First DETAILED Timing is preferred\n");
 771                 specs->misc |= FB_MISC_1ST_DETAIL;
 772         }
 773         if (c & 0x01) {
 774                 printk("      Display is GTF capable\n");
 775                 specs->gtf = 1;
 776         }
 777 }
 778
 779 static int edid_is_timing_block(unsigned char *block)
 780 {
 781         if ((block[0] != 0x00) || (block[1] != 0x00) ||
 782             (block[2] != 0x00) || (block[4] != 0x00))
 783                 return 1;
 784         else
 785                 return 0;
 786 }
 787
 788 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
 789 {
 790         int i;
 791         unsigned char *block;
 792
 793         if (edid == NULL || var == NULL)
 794                 return 1;
 795
 796         if (!(edid_checksum(edid)))
 797                 return 1;
 798
 799         if (!(edid_check_header(edid)))
 800                 return 1;
 801
 802         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 803
 804         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
 805                 if (edid_is_timing_block(block)) {
 806                         var->xres = var->xres_virtual = H_ACTIVE;
 807                         var->yres = var->yres_virtual = V_ACTIVE;
 808                         var->height = var->width = -1;
 809                         var->right_margin = H_SYNC_OFFSET;
 810                         var->left_margin = (H_ACTIVE + H_BLANKING) -
 811                                 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
 812                         var->upper_margin = V_BLANKING - V_SYNC_OFFSET -
 813                                 V_SYNC_WIDTH;
 814                         var->lower_margin = V_SYNC_OFFSET;
 815                         var->hsync_len = H_SYNC_WIDTH;
 816                         var->vsync_len = V_SYNC_WIDTH;
 817                         var->pixclock = PIXEL_CLOCK;
 818                         var->pixclock /= 1000;
 819                         var->pixclock = KHZ2PICOS(var->pixclock);
 820
 821                         if (HSYNC_POSITIVE)
 822                                 var->sync |= FB_SYNC_HOR_HIGH_ACT;
 823                         if (VSYNC_POSITIVE)
 824                                 var->sync |= FB_SYNC_VERT_HIGH_ACT;
 825                         return 0;
 826                 }
 827         }
 828         return 1;
 829 }
 830
 831 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
 832 {
 833         unsigned char *block;
 834         int i, found = 0;
 835
 836         if (edid == NULL)
 837                 return;
 838
 839         if (!(edid_checksum(edid)))
 840                 return;
 841
 842         if (!(edid_check_header(edid)))
 843                 return;
 844
 845         memset(specs, 0, sizeof(struct fb_monspecs));
 846
 847         specs->version = edid[EDID_STRUCT_VERSION];
 848         specs->revision = edid[EDID_STRUCT_REVISION];
 849
 850         DPRINTK("========================================\n");
 851         DPRINTK("Display Information (EDID)\n");
 852         DPRINTK("========================================\n");
 853         DPRINTK("   EDID Version %d.%d\n", (int) specs->version,
 854                (int) specs->revision);
 855
 856         parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);
 857
 858         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 859         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
 860                 if (edid_is_serial_block(block)) {
 861                         copy_string(block, specs->serial_no);
 862                         DPRINTK("   Serial Number: %s\n", specs->serial_no);
 863                 } else if (edid_is_ascii_block(block)) {
 864                         copy_string(block, specs->ascii);
 865                         DPRINTK("   ASCII Block: %s\n", specs->ascii);
 866                 } else if (edid_is_monitor_block(block)) {
 867                         copy_string(block, specs->monitor);
 868                         DPRINTK("   Monitor Name: %s\n", specs->monitor);
 869                 }
 870         }
 871
 872         DPRINTK("   Display Characteristics:\n");
 873         get_monspecs(edid, specs);
 874
 875         specs->modedb = fb_create_modedb(edid, &specs->modedb_len);
 876
 877         /*
 878          * Workaround for buggy EDIDs that sets that the first
 879          * detailed timing is preferred but has not detailed
 880          * timing specified
 881          */
 882         for (i = 0; i < specs->modedb_len; i++) {
 883                 if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {
 884                         found = 1;
 885                         break;
 886                 }
 887         }
 888
 889         if (!found)
 890                 specs->misc &= ~FB_MISC_1ST_DETAIL;
 891
 892         DPRINTK("========================================\n");
 893 }
 894
 895 /*
 896  * VESA Generalized Timing Formula (GTF)
 897  */
 898
 899 #define FLYBACK                     550
 900 #define V_FRONTPORCH                1
 901 #define H_OFFSET                    40
 902 #define H_SCALEFACTOR               20
 903 #define H_BLANKSCALE                128
 904 #define H_GRADIENT                  600
 905 #define C_VAL                       30
 906 #define M_VAL                       300
 907
 908 struct __fb_timings {
 909         u32 dclk;
 910         u32 hfreq;
 911         u32 vfreq;
 912         u32 hactive;
 913         u32 vactive;
 914         u32 hblank;
 915         u32 vblank;
 916         u32 htotal;
 917         u32 vtotal;
 918 };
 919
 920 /**
 921  * fb_get_vblank - get vertical blank time
 922  * @hfreq: horizontal freq
 923  *
 924  * DESCRIPTION:
 925  * vblank = right_margin + vsync_len + left_margin
 926  *
 927  *    given: right_margin = 1 (V_FRONTPORCH)
 928  *           vsync_len    = 3
 929  *           flyback      = 550
 930  *
 931  *                          flyback * hfreq
 932  *           left_margin  = --------------- - vsync_len
 933  *                           1000000
 934  */
 935 static u32 fb_get_vblank(u32 hfreq)
 936 {
 937         u32 vblank;
 938
 939         vblank = (hfreq * FLYBACK)/1000;
 940         vblank = (vblank + 500)/1000;
 941         return (vblank + V_FRONTPORCH);
 942 }
 943
 944 /**
 945  * fb_get_hblank_by_freq - get horizontal blank time given hfreq
 946  * @hfreq: horizontal freq
 947  * @xres: horizontal resolution in pixels
 948  *
 949  * DESCRIPTION:
 950  *
 951  *           xres * duty_cycle
 952  * hblank = ------------------
 953  *           100 - duty_cycle
 954  *
 955  * duty cycle = percent of htotal assigned to inactive display
 956  * duty cycle = C - (M/Hfreq)
 957  *
 958  * where: C = ((offset - scale factor) * blank_scale)
 959  *            -------------------------------------- + scale factor
 960  *                        256
 961  *        M = blank_scale * gradient
 962  *
 963  */
 964 static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
 965 {
 966         u32 c_val, m_val, duty_cycle, hblank;
 967
 968         c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 +
 969                  H_SCALEFACTOR) * 1000;
 970         m_val = (H_BLANKSCALE * H_GRADIENT)/256;
 971         m_val = (m_val * 1000000)/hfreq;
 972         duty_cycle = c_val - m_val;
 973         hblank = (xres * duty_cycle)/(100000 - duty_cycle);
 974         return (hblank);
 975 }
 976
 977 /**
 978  * fb_get_hblank_by_dclk - get horizontal blank time given pixelclock
 979  * @dclk: pixelclock in Hz
 980  * @xres: horizontal resolution in pixels
 981  *
 982  * DESCRIPTION:
 983  *
 984  *           xres * duty_cycle
 985  * hblank = ------------------
 986  *           100 - duty_cycle
 987  *
 988  * duty cycle = percent of htotal assigned to inactive display
 989  * duty cycle = C - (M * h_period)
 990  *
 991  * where: h_period = SQRT(100 - C + (0.4 * xres * M)/dclk) + C - 100
 992  *                   -----------------------------------------------
 993  *                                    2 * M
 994  *        M = 300;
 995  *        C = 30;
 996
 997  */
 998 static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)
 999 {
1000         u32 duty_cycle, h_period, hblank;
1001
1002         dclk /= 1000;
1003         h_period = 100 - C_VAL;
1004         h_period *= h_period;
1005         h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);
1006         h_period *=10000;
1007
1008         h_period = int_sqrt(h_period);
1009         h_period -= (100 - C_VAL) * 100;
1010         h_period *= 1000;
1011         h_period /= 2 * M_VAL;
1012
1013         duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;
1014         hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;
1015         hblank &= ~15;
1016         return (hblank);
1017 }
1018
1019 /**
1020  * fb_get_hfreq - estimate hsync
1021  * @vfreq: vertical refresh rate
1022  * @yres: vertical resolution
1023  *
1024  * DESCRIPTION:
1025  *
1026  *          (yres + front_port) * vfreq * 1000000
1027  * hfreq = -------------------------------------
1028  *          (1000000 - (vfreq * FLYBACK)
1029  *
1030  */
1031
1032 static u32 fb_get_hfreq(u32 vfreq, u32 yres)
1033 {
1034         u32 divisor, hfreq;
1035
1036         divisor = (1000000 - (vfreq * FLYBACK))/1000;
1037         hfreq = (yres + V_FRONTPORCH) * vfreq  * 1000;
1038         return (hfreq/divisor);
1039 }
1040
1041 static void fb_timings_vfreq(struct __fb_timings *timings)
1042 {
1043         timings->hfreq = fb_get_hfreq(timings->vfreq, timings->vactive);
1044         timings->vblank = fb_get_vblank(timings->hfreq);
1045         timings->vtotal = timings->vactive + timings->vblank;
1046         timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1047                                                  timings->hactive);
1048         timings->htotal = timings->hactive + timings->hblank;
1049         timings->dclk = timings->htotal * timings->hfreq;
1050 }
1051
1052 static void fb_timings_hfreq(struct __fb_timings *timings)
1053 {
1054         timings->vblank = fb_get_vblank(timings->hfreq);
1055         timings->vtotal = timings->vactive + timings->vblank;
1056         timings->vfreq = timings->hfreq/timings->vtotal;
1057         timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1058                                                  timings->hactive);
1059         timings->htotal = timings->hactive + timings->hblank;
1060         timings->dclk = timings->htotal * timings->hfreq;
1061 }
1062
1063 static void fb_timings_dclk(struct __fb_timings *timings)
1064 {
1065         timings->hblank = fb_get_hblank_by_dclk(timings->dclk,
1066                                                 timings->hactive);
1067         timings->htotal = timings->hactive + timings->hblank;
1068         timings->hfreq = timings->dclk/timings->htotal;
1069         timings->vblank = fb_get_vblank(timings->hfreq);
1070         timings->vtotal = timings->vactive + timings->vblank;
1071         timings->vfreq = timings->hfreq/timings->vtotal;
1072 }
1073
1074 /*
1075  * fb_get_mode - calculates video mode using VESA GTF
1076  * @flags: if: 0 - maximize vertical refresh rate
1077  *             1 - vrefresh-driven calculation;
1078  *             2 - hscan-driven calculation;
1079  *             3 - pixelclock-driven calculation;
1080  * @val: depending on @flags, ignored, vrefresh, hsync or pixelclock
1081  * @var: pointer to fb_var_screeninfo
1082  * @info: pointer to fb_info
1083  *
1084  * DESCRIPTION:
1085  * Calculates video mode based on monitor specs using VESA GTF.
1086  * The GTF is best for VESA GTF compliant monitors but is
1087  * specifically formulated to work for older monitors as well.
1088  *
1089  * If @flag==0, the function will attempt to maximize the
1090  * refresh rate.  Otherwise, it will calculate timings based on
1091  * the flag and accompanying value.
1092  *
1093  * If FB_IGNOREMON bit is set in @flags, monitor specs will be
1094  * ignored and @var will be filled with the calculated timings.
1095  *
1096  * All calculations are based on the VESA GTF Spreadsheet
1097  * available at VESA's public ftp (http://www.vesa.org).
1098  *
1099  * NOTES:
1100  * The timings generated by the GTF will be different from VESA
1101  * DMT.  It might be a good idea to keep a table of standard
1102  * VESA modes as well.  The GTF may also not work for some displays,
1103  * such as, and especially, analog TV.
1104  *
1105  * REQUIRES:
1106  * A valid info->monspecs, otherwise 'safe numbers' will be used.
1107  */
1108 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)
1109 {
1110         struct __fb_timings *timings;
1111         u32 interlace = 1, dscan = 1;
1112         u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;
1113
1114
1115         timings = kzalloc(sizeof(struct __fb_timings), GFP_KERNEL);
1116
1117         if (!timings)
1118                 return -ENOMEM;
1119
1120         /*
1121          * If monspecs are invalid, use values that are enough
1122          * for 640x480@60
1123          */
1124         if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||
1125             !info->monspecs.dclkmax ||
1126             info->monspecs.hfmax < info->monspecs.hfmin ||
1127             info->monspecs.vfmax < info->monspecs.vfmin ||
1128             info->monspecs.dclkmax < info->monspecs.dclkmin) {
1129                 hfmin = 29000; hfmax = 30000;
1130                 vfmin = 60; vfmax = 60;
1131                 dclkmin = 0; dclkmax = 25000000;
1132         } else {
1133                 hfmin = info->monspecs.hfmin;
1134                 hfmax = info->monspecs.hfmax;
1135                 vfmin = info->monspecs.vfmin;
1136                 vfmax = info->monspecs.vfmax;
1137                 dclkmin = info->monspecs.dclkmin;
1138                 dclkmax = info->monspecs.dclkmax;
1139         }
1140
1141         timings->hactive = var->xres;
1142         timings->vactive = var->yres;
1143         if (var->vmode & FB_VMODE_INTERLACED) {
1144                 timings->vactive /= 2;
1145                 interlace = 2;
1146         }
1147         if (var->vmode & FB_VMODE_DOUBLE) {
1148                 timings->vactive *= 2;
1149                 dscan = 2;
1150         }
1151
1152         switch (flags & ~FB_IGNOREMON) {
1153         case FB_MAXTIMINGS: /* maximize refresh rate */
1154                 timings->hfreq = hfmax;
1155                 fb_timings_hfreq(timings);
1156                 if (timings->vfreq > vfmax) {
1157                         timings->vfreq = vfmax;
1158                         fb_timings_vfreq(timings);
1159                 }
1160                 if (timings->dclk > dclkmax) {
1161                         timings->dclk = dclkmax;
1162                         fb_timings_dclk(timings);
1163                 }
1164                 break;
1165         case FB_VSYNCTIMINGS: /* vrefresh driven */
1166                 timings->vfreq = val;
1167                 fb_timings_vfreq(timings);
1168                 break;
1169         case FB_HSYNCTIMINGS: /* hsync driven */
1170                 timings->hfreq = val;
1171                 fb_timings_hfreq(timings);
1172                 break;
1173         case FB_DCLKTIMINGS: /* pixelclock driven */
1174                 timings->dclk = PICOS2KHZ(val) * 1000;
1175                 fb_timings_dclk(timings);
1176                 break;
1177         default:
1178                 err = -EINVAL;
1179
1180         }
1181
1182         if (err || (!(flags & FB_IGNOREMON) &&
1183             (timings->vfreq < vfmin || timings->vfreq > vfmax ||
1184              timings->hfreq < hfmin || timings->hfreq > hfmax ||
1185              timings->dclk < dclkmin || timings->dclk > dclkmax))) {
1186                 err = -EINVAL;
1187         } else {
1188                 var->pixclock = KHZ2PICOS(timings->dclk/1000);
1189                 var->hsync_len = (timings->htotal * 8)/100;
1190                 var->right_margin = (timings->hblank/2) - var->hsync_len;
1191                 var->left_margin = timings->hblank - var->right_margin -
1192                         var->hsync_len;
1193                 var->vsync_len = (3 * interlace)/dscan;
1194                 var->lower_margin = (1 * interlace)/dscan;
1195                 var->upper_margin = (timings->vblank * interlace)/dscan -
1196                         (var->vsync_len + var->lower_margin);
1197         }
1198
1199         kfree(timings);
1200         return err;
1201 }
1202 #else
1203 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
1204 {
1205         return 1;
1206 }
1207 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1208 {
1209         specs = NULL;
1210 }
1211 void fb_destroy_modedb(struct fb_videomode *modedb)
1212 {
1213 }
1214 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
1215                 struct fb_info *info)
1216 {
1217         return -EINVAL;
1218 }
1219 #endif /* CONFIG_FB_MODE_HELPERS */
1220
1221 /*
1222  * fb_validate_mode - validates var against monitor capabilities
1223  * @var: pointer to fb_var_screeninfo
1224  * @info: pointer to fb_info
1225  *
1226  * DESCRIPTION:
1227  * Validates video mode against monitor capabilities specified in
1228  * info->monspecs.
1229  *
1230  * REQUIRES:
1231  * A valid info->monspecs.
1232  */
1233 int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
1234 {
1235         u32 hfreq, vfreq, htotal, vtotal, pixclock;
1236         u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
1237
1238         /*
1239          * If monspecs are invalid, use values that are enough
1240          * for 640x480@60
1241          */
1242         if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
1243             !info->monspecs.dclkmax ||
1244             info->monspecs.hfmax < info->monspecs.hfmin ||
1245             info->monspecs.vfmax < info->monspecs.vfmin ||
1246             info->monspecs.dclkmax < info->monspecs.dclkmin) {
1247                 hfmin = 29000; hfmax = 30000;
1248                 vfmin = 60; vfmax = 60;
1249                 dclkmin = 0; dclkmax = 25000000;
1250         } else {
1251                 hfmin = info->monspecs.hfmin;
1252                 hfmax = info->monspecs.hfmax;
1253                 vfmin = info->monspecs.vfmin;
1254                 vfmax = info->monspecs.vfmax;
1255                 dclkmin = info->monspecs.dclkmin;
1256                 dclkmax = info->monspecs.dclkmax;
1257         }
1258
1259         if (!var->pixclock)
1260                 return -EINVAL;
1261         pixclock = PICOS2KHZ(var->pixclock) * 1000;
1262
1263         htotal = var->xres + var->right_margin + var->hsync_len +
1264                 var->left_margin;
1265         vtotal = var->yres + var->lower_margin + var->vsync_len +
1266                 var->upper_margin;
1267
1268         if (var->vmode & FB_VMODE_INTERLACED)
1269                 vtotal /= 2;
1270         if (var->vmode & FB_VMODE_DOUBLE)
1271                 vtotal *= 2;
1272
1273         hfreq = pixclock/htotal;
1274         hfreq = (hfreq + 500) / 1000 * 1000;
1275
1276         vfreq = hfreq/vtotal;
1277
1278         return (vfreq < vfmin || vfreq > vfmax ||
1279                 hfreq < hfmin || hfreq > hfmax ||
1280                 pixclock < dclkmin || pixclock > dclkmax) ?
1281                 -EINVAL : 0;
1282 }
1283
1284 #if defined(__i386__)
1285 #include <linux/pci.h>
1286
1287 /*
1288  * We need to ensure that the EDID block is only returned for
1289  * the primary graphics adapter.
1290  */
1291
1292 const unsigned char *fb_firmware_edid(struct device *device)
1293 {
1294         struct pci_dev *dev = NULL;
1295         struct resource *res = NULL;
1296         unsigned char *edid = NULL;
1297
1298         if (device)
1299                 dev = to_pci_dev(device);
1300
1301         if (dev)
1302                 res = &dev->resource[PCI_ROM_RESOURCE];
1303
1304         if (res && res->flags & IORESOURCE_ROM_SHADOW)
1305                 edid = edid_info.dummy;
1306
1307         return edid;
1308 }
1309 #else
1310 const unsigned char *fb_firmware_edid(struct device *device)
1311 {
1312         return NULL;
1313 }
1314 #endif /* _i386_ */
1315
1316 EXPORT_SYMBOL(fb_parse_edid);
1317 EXPORT_SYMBOL(fb_edid_to_monspecs);
1318 EXPORT_SYMBOL(fb_firmware_edid);
1319 EXPORT_SYMBOL(fb_get_mode);
1320 EXPORT_SYMBOL(fb_validate_mode);
1321 EXPORT_SYMBOL(fb_destroy_modedb);