drivers/video/fbmon.c

   1 /*
   2  * linux/drivers/video/fbmon.c
   3  *
   4  * Copyright (C) 2002 James Simmons <jsimmons@users.sf.net>
   5  *
   6  * Credits:
   7  *
   8  * The EDID Parser is a conglomeration from the following sources:
   9  *
  10  *   1. SciTech SNAP Graphics Architecture
  11  *      Copyright (C) 1991-2002 SciTech Software, Inc. All rights reserved.
  12  *
  13  *   2. XFree86 4.3.0, interpret_edid.c
  14  *      Copyright 1998 by Egbert Eich <Egbert.Eich@Physik.TU-Darmstadt.DE>
  15  *
  16  *   3. John Fremlin <vii@users.sourceforge.net> and
  17  *      Ani Joshi <ajoshi@unixbox.com>
  18  *
  19  * Generalized Timing Formula is derived from:
  20  *
  21  *      GTF Spreadsheet by Andy Morrish (1/5/97)
  22  *      available at http://www.vesa.org
  23  *
  24  * This file is subject to the terms and conditions of the GNU General Public
  25  * License.  See the file COPYING in the main directory of this archive
  26  * for more details.
  27  *
  28  */
  29 #include <linux/fb.h>
  30 #include <linux/module.h>
  31 #include <linux/pci.h>
  32 #include <linux/slab.h>
  33 #include <video/edid.h>
  34 #ifdef CONFIG_PPC_OF
  35 #include <asm/prom.h>
  36 #include <asm/pci-bridge.h>
  37 #endif
  38 #include "edid.h"
  39
  40 /*
  41  * EDID parser
  42  */
  43
  44 #undef DEBUG  /* define this for verbose EDID parsing output */
  45
  46 #ifdef DEBUG
  47 #define DPRINTK(fmt, args...) printk(fmt,## args)
  48 #else
  49 #define DPRINTK(fmt, args...)
  50 #endif
  51
  52 #define FBMON_FIX_HEADER  1
  53 #define FBMON_FIX_INPUT   2
  54 #define FBMON_FIX_TIMINGS 3
  55
  56 #ifdef CONFIG_FB_MODE_HELPERS
  57 struct broken_edid {
  58         u8  manufacturer[4];
  59         u32 model;
  60         u32 fix;
  61 };
  62
  63 static const struct broken_edid brokendb[] = {
  64         /* DEC FR-PCXAV-YZ */
  65         {
  66                 .manufacturer = "DEC",
  67                 .model        = 0x073a,
  68                 .fix          = FBMON_FIX_HEADER,
  69         },
  70         /* ViewSonic PF775a */
  71         {
  72                 .manufacturer = "VSC",
  73                 .model        = 0x5a44,
  74                 .fix          = FBMON_FIX_INPUT,
  75         },
  76         /* Sharp UXGA? */
  77         {
  78                 .manufacturer = "SHP",
  79                 .model        = 0x138e,
  80                 .fix          = FBMON_FIX_TIMINGS,
  81         },
  82 };
  83
  84 static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
  85         0xff, 0xff, 0xff, 0x00
  86 };
  87
  88 static void copy_string(unsigned char *c, unsigned char *s)
  89 {
  90   int i;
  91   c = c + 5;
  92   for (i = 0; (i < 13 && *c != 0x0A); i++)
  93     *(s++) = *(c++);
  94   *s = 0;
  95   while (i-- && (*--s == 0x20)) *s = 0;
  96 }
  97
  98 static int edid_is_serial_block(unsigned char *block)
  99 {
 100         if ((block[0] == 0x00) && (block[1] == 0x00) &&
 101             (block[2] == 0x00) && (block[3] == 0xff) &&
 102             (block[4] == 0x00))
 103                 return 1;
 104         else
 105                 return 0;
 106 }
 107
 108 static int edid_is_ascii_block(unsigned char *block)
 109 {
 110         if ((block[0] == 0x00) && (block[1] == 0x00) &&
 111             (block[2] == 0x00) && (block[3] == 0xfe) &&
 112             (block[4] == 0x00))
 113                 return 1;
 114         else
 115                 return 0;
 116 }
 117
 118 static int edid_is_limits_block(unsigned char *block)
 119 {
 120         if ((block[0] == 0x00) && (block[1] == 0x00) &&
 121             (block[2] == 0x00) && (block[3] == 0xfd) &&
 122             (block[4] == 0x00))
 123                 return 1;
 124         else
 125                 return 0;
 126 }
 127
 128 static int edid_is_monitor_block(unsigned char *block)
 129 {
 130         if ((block[0] == 0x00) && (block[1] == 0x00) &&
 131             (block[2] == 0x00) && (block[3] == 0xfc) &&
 132             (block[4] == 0x00))
 133                 return 1;
 134         else
 135                 return 0;
 136 }
 137
 138 static int edid_is_timing_block(unsigned char *block)
 139 {
 140         if ((block[0] != 0x00) || (block[1] != 0x00) ||
 141             (block[2] != 0x00) || (block[4] != 0x00))
 142                 return 1;
 143         else
 144                 return 0;
 145 }
 146
 147 static int check_edid(unsigned char *edid)
 148 {
 149         unsigned char *block = edid + ID_MANUFACTURER_NAME, manufacturer[4];
 150         unsigned char *b;
 151         u32 model;
 152         int i, fix = 0, ret = 0;
 153
 154         manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
 155         manufacturer[1] = ((block[0] & 0x03) << 3) +
 156                 ((block[1] & 0xe0) >> 5) + '@';
 157         manufacturer[2] = (block[1] & 0x1f) + '@';
 158         manufacturer[3] = 0;
 159         model = block[2] + (block[3] << 8);
 160
 161         for (i = 0; i < ARRAY_SIZE(brokendb); i++) {
 162                 if (!strncmp(manufacturer, brokendb[i].manufacturer, 4) &&
 163                         brokendb[i].model == model) {
 164                         fix = brokendb[i].fix;
 165                         break;
 166                 }
 167         }
 168
 169         switch (fix) {
 170         case FBMON_FIX_HEADER:
 171                 for (i = 0; i < 8; i++) {
 172                         if (edid[i] != edid_v1_header[i]) {
 173                                 ret = fix;
 174                                 break;
 175                         }
 176                 }
 177                 break;
 178         case FBMON_FIX_INPUT:
 179                 b = edid + EDID_STRUCT_DISPLAY;
 180                 /* Only if display is GTF capable will
 181                    the input type be reset to analog */
 182                 if (b[4] & 0x01 && b[0] & 0x80)
 183                         ret = fix;
 184                 break;
 185         case FBMON_FIX_TIMINGS:
 186                 b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 187                 ret = fix;
 188
 189                 for (i = 0; i < 4; i++) {
 190                         if (edid_is_limits_block(b)) {
 191                                 ret = 0;
 192                                 break;
 193                         }
 194
 195                         b += DETAILED_TIMING_DESCRIPTION_SIZE;
 196                 }
 197
 198                 break;
 199         }
 200
 201         if (ret)
 202                 printk("fbmon: The EDID Block of "
 203                        "Manufacturer: %s Model: 0x%x is known to "
 204                        "be broken,\n",  manufacturer, model);
 205
 206         return ret;
 207 }
 208
 209 static void fix_edid(unsigned char *edid, int fix)
 210 {
 211         int i;
 212         unsigned char *b, csum = 0;
 213
 214         switch (fix) {
 215         case FBMON_FIX_HEADER:
 216                 printk("fbmon: trying a header reconstruct\n");
 217                 memcpy(edid, edid_v1_header, 8);
 218                 break;
 219         case FBMON_FIX_INPUT:
 220                 printk("fbmon: trying to fix input type\n");
 221                 b = edid + EDID_STRUCT_DISPLAY;
 222                 b[0] &= ~0x80;
 223                 edid[127] += 0x80;
 224                 break;
 225         case FBMON_FIX_TIMINGS:
 226                 printk("fbmon: trying to fix monitor timings\n");
 227                 b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 228                 for (i = 0; i < 4; i++) {
 229                         if (!(edid_is_serial_block(b) ||
 230                               edid_is_ascii_block(b) ||
 231                               edid_is_monitor_block(b) ||
 232                               edid_is_timing_block(b))) {
 233                                 b[0] = 0x00;
 234                                 b[1] = 0x00;
 235                                 b[2] = 0x00;
 236                                 b[3] = 0xfd;
 237                                 b[4] = 0x00;
 238                                 b[5] = 60;   /* vfmin */
 239                                 b[6] = 60;   /* vfmax */
 240                                 b[7] = 30;   /* hfmin */
 241                                 b[8] = 75;   /* hfmax */
 242                                 b[9] = 17;   /* pixclock - 170 MHz*/
 243                                 b[10] = 0;   /* GTF */
 244                                 break;
 245                         }
 246
 247                         b += DETAILED_TIMING_DESCRIPTION_SIZE;
 248                 }
 249
 250                 for (i = 0; i < EDID_LENGTH - 1; i++)
 251                         csum += edid[i];
 252
 253                 edid[127] = 256 - csum;
 254                 break;
 255         }
 256 }
 257
 258 static int edid_checksum(unsigned char *edid)
 259 {
 260         unsigned char csum = 0, all_null = 0;
 261         int i, err = 0, fix = check_edid(edid);
 262
 263         if (fix)
 264                 fix_edid(edid, fix);
 265
 266         for (i = 0; i < EDID_LENGTH; i++) {
 267                 csum += edid[i];
 268                 all_null |= edid[i];
 269         }
 270
 271         if (csum == 0x00 && all_null) {
 272                 /* checksum passed, everything's good */
 273                 err = 1;
 274         }
 275
 276         return err;
 277 }
 278
 279 static int edid_check_header(unsigned char *edid)
 280 {
 281         int i, err = 1, fix = check_edid(edid);
 282
 283         if (fix)
 284                 fix_edid(edid, fix);
 285
 286         for (i = 0; i < 8; i++) {
 287                 if (edid[i] != edid_v1_header[i])
 288                         err = 0;
 289         }
 290
 291         return err;
 292 }
 293
 294 static void parse_vendor_block(unsigned char *block, struct fb_monspecs *specs)
 295 {
 296         specs->manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
 297         specs->manufacturer[1] = ((block[0] & 0x03) << 3) +
 298                 ((block[1] & 0xe0) >> 5) + '@';
 299         specs->manufacturer[2] = (block[1] & 0x1f) + '@';
 300         specs->manufacturer[3] = 0;
 301         specs->model = block[2] + (block[3] << 8);
 302         specs->serial = block[4] + (block[5] << 8) +
 303                (block[6] << 16) + (block[7] << 24);
 304         specs->year = block[9] + 1990;
 305         specs->week = block[8];
 306         DPRINTK("   Manufacturer: %s\n", specs->manufacturer);
 307         DPRINTK("   Model: %x\n", specs->model);
 308         DPRINTK("   Serial#: %u\n", specs->serial);
 309         DPRINTK("   Year: %u Week %u\n", specs->year, specs->week);
 310 }
 311
 312 static void get_dpms_capabilities(unsigned char flags,
 313                                   struct fb_monspecs *specs)
 314 {
 315         specs->dpms = 0;
 316         if (flags & DPMS_ACTIVE_OFF)
 317                 specs->dpms |= FB_DPMS_ACTIVE_OFF;
 318         if (flags & DPMS_SUSPEND)
 319                 specs->dpms |= FB_DPMS_SUSPEND;
 320         if (flags & DPMS_STANDBY)
 321                 specs->dpms |= FB_DPMS_STANDBY;
 322         DPRINTK("      DPMS: Active %s, Suspend %s, Standby %s\n",
 323                (flags & DPMS_ACTIVE_OFF) ? "yes" : "no",
 324                (flags & DPMS_SUSPEND)    ? "yes" : "no",
 325                (flags & DPMS_STANDBY)    ? "yes" : "no");
 326 }
 327
 328 static void get_chroma(unsigned char *block, struct fb_monspecs *specs)
 329 {
 330         int tmp;
 331
 332         DPRINTK("      Chroma\n");
 333         /* Chromaticity data */
 334         tmp = ((block[5] & (3 << 6)) >> 6) | (block[0x7] << 2);
 335         tmp *= 1000;
 336         tmp += 512;
 337         specs->chroma.redx = tmp/1024;
 338         DPRINTK("         RedX:     0.%03d ", specs->chroma.redx);
 339
 340         tmp = ((block[5] & (3 << 4)) >> 4) | (block[0x8] << 2);
 341         tmp *= 1000;
 342         tmp += 512;
 343         specs->chroma.redy = tmp/1024;
 344         DPRINTK("RedY:     0.%03d\n", specs->chroma.redy);
 345
 346         tmp = ((block[5] & (3 << 2)) >> 2) | (block[0x9] << 2);
 347         tmp *= 1000;
 348         tmp += 512;
 349         specs->chroma.greenx = tmp/1024;
 350         DPRINTK("         GreenX:   0.%03d ", specs->chroma.greenx);
 351
 352         tmp = (block[5] & 3) | (block[0xa] << 2);
 353         tmp *= 1000;
 354         tmp += 512;
 355         specs->chroma.greeny = tmp/1024;
 356         DPRINTK("GreenY:   0.%03d\n", specs->chroma.greeny);
 357
 358         tmp = ((block[6] & (3 << 6)) >> 6) | (block[0xb] << 2);
 359         tmp *= 1000;
 360         tmp += 512;
 361         specs->chroma.bluex = tmp/1024;
 362         DPRINTK("         BlueX:    0.%03d ", specs->chroma.bluex);
 363
 364         tmp = ((block[6] & (3 << 4)) >> 4) | (block[0xc] << 2);
 365         tmp *= 1000;
 366         tmp += 512;
 367         specs->chroma.bluey = tmp/1024;
 368         DPRINTK("BlueY:    0.%03d\n", specs->chroma.bluey);
 369
 370         tmp = ((block[6] & (3 << 2)) >> 2) | (block[0xd] << 2);
 371         tmp *= 1000;
 372         tmp += 512;
 373         specs->chroma.whitex = tmp/1024;
 374         DPRINTK("         WhiteX:   0.%03d ", specs->chroma.whitex);
 375
 376         tmp = (block[6] & 3) | (block[0xe] << 2);
 377         tmp *= 1000;
 378         tmp += 512;
 379         specs->chroma.whitey = tmp/1024;
 380         DPRINTK("WhiteY:   0.%03d\n", specs->chroma.whitey);
 381 }
 382
 383 static void calc_mode_timings(int xres, int yres, int refresh,
 384                               struct fb_videomode *mode)
 385 {
 386         struct fb_var_screeninfo *var;
 387
 388         var = kzalloc(sizeof(struct fb_var_screeninfo), GFP_KERNEL);
 389
 390         if (var) {
 391                 var->xres = xres;
 392                 var->yres = yres;
 393                 fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON,
 394                             refresh, var, NULL);
 395                 mode->xres = xres;
 396                 mode->yres = yres;
 397                 mode->pixclock = var->pixclock;
 398                 mode->refresh = refresh;
 399                 mode->left_margin = var->left_margin;
 400                 mode->right_margin = var->right_margin;
 401                 mode->upper_margin = var->upper_margin;
 402                 mode->lower_margin = var->lower_margin;
 403                 mode->hsync_len = var->hsync_len;
 404                 mode->vsync_len = var->vsync_len;
 405                 mode->vmode = 0;
 406                 mode->sync = 0;
 407                 kfree(var);
 408         }
 409 }
 410
 411 static int get_est_timing(unsigned char *block, struct fb_videomode *mode)
 412 {
 413         int num = 0;
 414         unsigned char c;
 415
 416         c = block[0];
 417         if (c&0x80) {
 418                 calc_mode_timings(720, 400, 70, &mode[num]);
 419                 mode[num++].flag = FB_MODE_IS_CALCULATED;
 420                 DPRINTK("      720x400@70Hz\n");
 421         }
 422         if (c&0x40) {
 423                 calc_mode_timings(720, 400, 88, &mode[num]);
 424                 mode[num++].flag = FB_MODE_IS_CALCULATED;
 425                 DPRINTK("      720x400@88Hz\n");
 426         }
 427         if (c&0x20) {
 428                 mode[num++] = vesa_modes[3];
 429                 DPRINTK("      640x480@60Hz\n");
 430         }
 431         if (c&0x10) {
 432                 calc_mode_timings(640, 480, 67, &mode[num]);
 433                 mode[num++].flag = FB_MODE_IS_CALCULATED;
 434                 DPRINTK("      640x480@67Hz\n");
 435         }
 436         if (c&0x08) {
 437                 mode[num++] = vesa_modes[4];
 438                 DPRINTK("      640x480@72Hz\n");
 439         }
 440         if (c&0x04) {
 441                 mode[num++] = vesa_modes[5];
 442                 DPRINTK("      640x480@75Hz\n");
 443         }
 444         if (c&0x02) {
 445                 mode[num++] = vesa_modes[7];
 446                 DPRINTK("      800x600@56Hz\n");
 447         }
 448         if (c&0x01) {
 449                 mode[num++] = vesa_modes[8];
 450                 DPRINTK("      800x600@60Hz\n");
 451         }
 452
 453         c = block[1];
 454         if (c&0x80) {
 455                 mode[num++] = vesa_modes[9];
 456                 DPRINTK("      800x600@72Hz\n");
 457         }
 458         if (c&0x40) {
 459                 mode[num++] = vesa_modes[10];
 460                 DPRINTK("      800x600@75Hz\n");
 461         }
 462         if (c&0x20) {
 463                 calc_mode_timings(832, 624, 75, &mode[num]);
 464                 mode[num++].flag = FB_MODE_IS_CALCULATED;
 465                 DPRINTK("      832x624@75Hz\n");
 466         }
 467         if (c&0x10) {
 468                 mode[num++] = vesa_modes[12];
 469                 DPRINTK("      1024x768@87Hz Interlaced\n");
 470         }
 471         if (c&0x08) {
 472                 mode[num++] = vesa_modes[13];
 473                 DPRINTK("      1024x768@60Hz\n");
 474         }
 475         if (c&0x04) {
 476                 mode[num++] = vesa_modes[14];
 477                 DPRINTK("      1024x768@70Hz\n");
 478         }
 479         if (c&0x02) {
 480                 mode[num++] = vesa_modes[15];
 481                 DPRINTK("      1024x768@75Hz\n");
 482         }
 483         if (c&0x01) {
 484                 mode[num++] = vesa_modes[21];
 485                 DPRINTK("      1280x1024@75Hz\n");
 486         }
 487         c = block[2];
 488         if (c&0x80) {
 489                 mode[num++] = vesa_modes[17];
 490                 DPRINTK("      1152x870@75Hz\n");
 491         }
 492         DPRINTK("      Manufacturer's mask: %x\n",c&0x7F);
 493         return num;
 494 }
 495
 496 static int get_std_timing(unsigned char *block, struct fb_videomode *mode)
 497 {
 498         int xres, yres = 0, refresh, ratio, i;
 499
 500         xres = (block[0] + 31) * 8;
 501         if (xres <= 256)
 502                 return 0;
 503
 504         ratio = (block[1] & 0xc0) >> 6;
 505         switch (ratio) {
 506         case 0:
 507                 yres = xres;
 508                 break;
 509         case 1:
 510                 yres = (xres * 3)/4;
 511                 break;
 512         case 2:
 513                 yres = (xres * 4)/5;
 514                 break;
 515         case 3:
 516                 yres = (xres * 9)/16;
 517                 break;
 518         }
 519         refresh = (block[1] & 0x3f) + 60;
 520
 521         DPRINTK("      %dx%d@%dHz\n", xres, yres, refresh);
 522         for (i = 0; i < VESA_MODEDB_SIZE; i++) {
 523                 if (vesa_modes[i].xres == xres &&
 524                     vesa_modes[i].yres == yres &&
 525                     vesa_modes[i].refresh == refresh) {
 526                         *mode = vesa_modes[i];
 527                         mode->flag |= FB_MODE_IS_STANDARD;
 528                         return 1;
 529                 }
 530         }
 531         calc_mode_timings(xres, yres, refresh, mode);
 532         return 1;
 533 }
 534
 535 static int get_dst_timing(unsigned char *block,
 536                           struct fb_videomode *mode)
 537 {
 538         int j, num = 0;
 539
 540         for (j = 0; j < 6; j++, block += STD_TIMING_DESCRIPTION_SIZE)
 541                 num += get_std_timing(block, &mode[num]);
 542
 543         return num;
 544 }
 545
 546 static void get_detailed_timing(unsigned char *block,
 547                                 struct fb_videomode *mode)
 548 {
 549         mode->xres = H_ACTIVE;
 550         mode->yres = V_ACTIVE;
 551         mode->pixclock = PIXEL_CLOCK;
 552         mode->pixclock /= 1000;
 553         mode->pixclock = KHZ2PICOS(mode->pixclock);
 554         mode->right_margin = H_SYNC_OFFSET;
 555         mode->left_margin = (H_ACTIVE + H_BLANKING) -
 556                 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
 557         mode->upper_margin = V_BLANKING - V_SYNC_OFFSET -
 558                 V_SYNC_WIDTH;
 559         mode->lower_margin = V_SYNC_OFFSET;
 560         mode->hsync_len = H_SYNC_WIDTH;
 561         mode->vsync_len = V_SYNC_WIDTH;
 562         if (HSYNC_POSITIVE)
 563                 mode->sync |= FB_SYNC_HOR_HIGH_ACT;
 564         if (VSYNC_POSITIVE)
 565                 mode->sync |= FB_SYNC_VERT_HIGH_ACT;
 566         mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *
 567                                      (V_ACTIVE + V_BLANKING));
 568         if (INTERLACED) {
 569                 mode->yres *= 2;
 570                 mode->upper_margin *= 2;
 571                 mode->lower_margin *= 2;
 572                 mode->vsync_len *= 2;
 573                 mode->vmode |= FB_VMODE_INTERLACED;
 574         }
 575         mode->flag = FB_MODE_IS_DETAILED;
 576
 577         DPRINTK("      %d MHz ",  PIXEL_CLOCK/1000000);
 578         DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET,
 579                H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING);
 580         DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET,
 581                V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING);
 582         DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-",
 583                (VSYNC_POSITIVE) ? "+" : "-");
 584 }
 585
 586 /**
 587  * fb_create_modedb - create video mode database
 588  * @edid: EDID data
 589  * @dbsize: database size
 590  *
 591  * RETURNS: struct fb_videomode, @dbsize contains length of database
 592  *
 593  * DESCRIPTION:
 594  * This function builds a mode database using the contents of the EDID
 595  * data
 596  */
 597 static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize)
 598 {
 599         struct fb_videomode *mode, *m;
 600         unsigned char *block;
 601         int num = 0, i, first = 1;
 602
 603         mode = kzalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
 604         if (mode == NULL)
 605                 return NULL;
 606
 607         if (edid == NULL || !edid_checksum(edid) ||
 608             !edid_check_header(edid)) {
 609                 kfree(mode);
 610                 return NULL;
 611         }
 612
 613         *dbsize = 0;
 614
 615         DPRINTK("   Detailed Timings\n");
 616         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 617         for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
 618                 if (!(block[0] == 0x00 && block[1] == 0x00)) {
 619                         get_detailed_timing(block, &mode[num]);
 620                         if (first) {
 621                                 mode[num].flag |= FB_MODE_IS_FIRST;
 622                                 first = 0;
 623                         }
 624                         num++;
 625                 }
 626         }
 627
 628         DPRINTK("   Supported VESA Modes\n");
 629         block = edid + ESTABLISHED_TIMING_1;
 630         num += get_est_timing(block, &mode[num]);
 631
 632         DPRINTK("   Standard Timings\n");
 633         block = edid + STD_TIMING_DESCRIPTIONS_START;
 634         for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE)
 635                 num += get_std_timing(block, &mode[num]);
 636
 637         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 638         for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
 639                 if (block[0] == 0x00 && block[1] == 0x00 && block[3] == 0xfa)
 640                         num += get_dst_timing(block + 5, &mode[num]);
 641         }
 642
 643         /* Yikes, EDID data is totally useless */
 644         if (!num) {
 645                 kfree(mode);
 646                 return NULL;
 647         }
 648
 649         *dbsize = num;
 650         m = kmalloc(num * sizeof(struct fb_videomode), GFP_KERNEL);
 651         if (!m)
 652                 return mode;
 653         memmove(m, mode, num * sizeof(struct fb_videomode));
 654         kfree(mode);
 655         return m;
 656 }
 657
 658 /**
 659  * fb_destroy_modedb - destroys mode database
 660  * @modedb: mode database to destroy
 661  *
 662  * DESCRIPTION:
 663  * Destroy mode database created by fb_create_modedb
 664  */
 665 void fb_destroy_modedb(struct fb_videomode *modedb)
 666 {
 667         kfree(modedb);
 668 }
 669
 670 static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
 671 {
 672         int i, retval = 1;
 673         unsigned char *block;
 674
 675         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 676
 677         DPRINTK("      Monitor Operating Limits: ");
 678
 679         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
 680                 if (edid_is_limits_block(block)) {
 681                         specs->hfmin = H_MIN_RATE * 1000;
 682                         specs->hfmax = H_MAX_RATE * 1000;
 683                         specs->vfmin = V_MIN_RATE;
 684                         specs->vfmax = V_MAX_RATE;
 685                         specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;
 686                         specs->gtf = (GTF_SUPPORT) ? 1 : 0;
 687                         retval = 0;
 688                         DPRINTK("From EDID\n");
 689                         break;
 690                 }
 691         }
 692
 693         /* estimate monitor limits based on modes supported */
 694         if (retval) {
 695                 struct fb_videomode *modes, *mode;
 696                 int num_modes, hz, hscan, pixclock;
 697                 int vtotal, htotal;
 698
 699                 modes = fb_create_modedb(edid, &num_modes);
 700                 if (!modes) {
 701                         DPRINTK("None Available\n");
 702                         return 1;
 703                 }
 704
 705                 retval = 0;
 706                 for (i = 0; i < num_modes; i++) {
 707                         mode = &modes[i];
 708                         pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
 709                         htotal = mode->xres + mode->right_margin + mode->hsync_len
 710                                 + mode->left_margin;
 711                         vtotal = mode->yres + mode->lower_margin + mode->vsync_len
 712                                 + mode->upper_margin;
 713
 714                         if (mode->vmode & FB_VMODE_INTERLACED)
 715                                 vtotal /= 2;
 716
 717                         if (mode->vmode & FB_VMODE_DOUBLE)
 718                                 vtotal *= 2;
 719
 720                         hscan = (pixclock + htotal / 2) / htotal;
 721                         hscan = (hscan + 500) / 1000 * 1000;
 722                         hz = (hscan + vtotal / 2) / vtotal;
 723
 724                         if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
 725                                 specs->dclkmax = pixclock;
 726
 727                         if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
 728                                 specs->dclkmin = pixclock;
 729
 730                         if (specs->hfmax == 0 || specs->hfmax < hscan)
 731                                 specs->hfmax = hscan;
 732
 733                         if (specs->hfmin == 0 || specs->hfmin > hscan)
 734                                 specs->hfmin = hscan;
 735
 736                         if (specs->vfmax == 0 || specs->vfmax < hz)
 737                                 specs->vfmax = hz;
 738
 739                         if (specs->vfmin == 0 || specs->vfmin > hz)
 740                                 specs->vfmin = hz;
 741                 }
 742                 DPRINTK("Extrapolated\n");
 743                 fb_destroy_modedb(modes);
 744         }
 745         DPRINTK("           H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",
 746                 specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,
 747                 specs->vfmax, specs->dclkmax/1000000);
 748         return retval;
 749 }
 750
 751 static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
 752 {
 753         unsigned char c, *block;
 754
 755         block = edid + EDID_STRUCT_DISPLAY;
 756
 757         fb_get_monitor_limits(edid, specs);
 758
 759         c = block[0] & 0x80;
 760         specs->input = 0;
 761         if (c) {
 762                 specs->input |= FB_DISP_DDI;
 763                 DPRINTK("      Digital Display Input");
 764         } else {
 765                 DPRINTK("      Analog Display Input: Input Voltage - ");
 766                 switch ((block[0] & 0x60) >> 5) {
 767                 case 0:
 768                         DPRINTK("0.700V/0.300V");
 769                         specs->input |= FB_DISP_ANA_700_300;
 770                         break;
 771                 case 1:
 772                         DPRINTK("0.714V/0.286V");
 773                         specs->input |= FB_DISP_ANA_714_286;
 774                         break;
 775                 case 2:
 776                         DPRINTK("1.000V/0.400V");
 777                         specs->input |= FB_DISP_ANA_1000_400;
 778                         break;
 779                 case 3:
 780                         DPRINTK("0.700V/0.000V");
 781                         specs->input |= FB_DISP_ANA_700_000;
 782                         break;
 783                 }
 784         }
 785         DPRINTK("\n      Sync: ");
 786         c = block[0] & 0x10;
 787         if (c)
 788                 DPRINTK("      Configurable signal level\n");
 789         c = block[0] & 0x0f;
 790         specs->signal = 0;
 791         if (c & 0x10) {
 792                 DPRINTK("Blank to Blank ");
 793                 specs->signal |= FB_SIGNAL_BLANK_BLANK;
 794         }
 795         if (c & 0x08) {
 796                 DPRINTK("Separate ");
 797                 specs->signal |= FB_SIGNAL_SEPARATE;
 798         }
 799         if (c & 0x04) {
 800                 DPRINTK("Composite ");
 801                 specs->signal |= FB_SIGNAL_COMPOSITE;
 802         }
 803         if (c & 0x02) {
 804                 DPRINTK("Sync on Green ");
 805                 specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
 806         }
 807         if (c & 0x01) {
 808                 DPRINTK("Serration on ");
 809                 specs->signal |= FB_SIGNAL_SERRATION_ON;
 810         }
 811         DPRINTK("\n");
 812         specs->max_x = block[1];
 813         specs->max_y = block[2];
 814         DPRINTK("      Max H-size in cm: ");
 815         if (specs->max_x)
 816                 DPRINTK("%d\n", specs->max_x);
 817         else
 818                 DPRINTK("variable\n");
 819         DPRINTK("      Max V-size in cm: ");
 820         if (specs->max_y)
 821                 DPRINTK("%d\n", specs->max_y);
 822         else
 823                 DPRINTK("variable\n");
 824
 825         c = block[3];
 826         specs->gamma = c+100;
 827         DPRINTK("      Gamma: ");
 828         DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
 829
 830         get_dpms_capabilities(block[4], specs);
 831
 832         switch ((block[4] & 0x18) >> 3) {
 833         case 0:
 834                 DPRINTK("      Monochrome/Grayscale\n");
 835                 specs->input |= FB_DISP_MONO;
 836                 break;
 837         case 1:
 838                 DPRINTK("      RGB Color Display\n");
 839                 specs->input |= FB_DISP_RGB;
 840                 break;
 841         case 2:
 842                 DPRINTK("      Non-RGB Multicolor Display\n");
 843                 specs->input |= FB_DISP_MULTI;
 844                 break;
 845         default:
 846                 DPRINTK("      Unknown\n");
 847                 specs->input |= FB_DISP_UNKNOWN;
 848                 break;
 849         }
 850
 851         get_chroma(block, specs);
 852
 853         specs->misc = 0;
 854         c = block[4] & 0x7;
 855         if (c & 0x04) {
 856                 DPRINTK("      Default color format is primary\n");
 857                 specs->misc |= FB_MISC_PRIM_COLOR;
 858         }
 859         if (c & 0x02) {
 860                 DPRINTK("      First DETAILED Timing is preferred\n");
 861                 specs->misc |= FB_MISC_1ST_DETAIL;
 862         }
 863         if (c & 0x01) {
 864                 printk("      Display is GTF capable\n");
 865                 specs->gtf = 1;
 866         }
 867 }
 868
 869 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
 870 {
 871         int i;
 872         unsigned char *block;
 873
 874         if (edid == NULL || var == NULL)
 875                 return 1;
 876
 877         if (!(edid_checksum(edid)))
 878                 return 1;
 879
 880         if (!(edid_check_header(edid)))
 881                 return 1;
 882
 883         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 884
 885         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
 886                 if (edid_is_timing_block(block)) {
 887                         var->xres = var->xres_virtual = H_ACTIVE;
 888                         var->yres = var->yres_virtual = V_ACTIVE;
 889                         var->height = var->width = 0;
 890                         var->right_margin = H_SYNC_OFFSET;
 891                         var->left_margin = (H_ACTIVE + H_BLANKING) -
 892                                 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
 893                         var->upper_margin = V_BLANKING - V_SYNC_OFFSET -
 894                                 V_SYNC_WIDTH;
 895                         var->lower_margin = V_SYNC_OFFSET;
 896                         var->hsync_len = H_SYNC_WIDTH;
 897                         var->vsync_len = V_SYNC_WIDTH;
 898                         var->pixclock = PIXEL_CLOCK;
 899                         var->pixclock /= 1000;
 900                         var->pixclock = KHZ2PICOS(var->pixclock);
 901
 902                         if (HSYNC_POSITIVE)
 903                                 var->sync |= FB_SYNC_HOR_HIGH_ACT;
 904                         if (VSYNC_POSITIVE)
 905                                 var->sync |= FB_SYNC_VERT_HIGH_ACT;
 906                         return 0;
 907                 }
 908         }
 909         return 1;
 910 }
 911
 912 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
 913 {
 914         unsigned char *block;
 915         int i, found = 0;
 916
 917         if (edid == NULL)
 918                 return;
 919
 920         if (!(edid_checksum(edid)))
 921                 return;
 922
 923         if (!(edid_check_header(edid)))
 924                 return;
 925
 926         memset(specs, 0, sizeof(struct fb_monspecs));
 927
 928         specs->version = edid[EDID_STRUCT_VERSION];
 929         specs->revision = edid[EDID_STRUCT_REVISION];
 930
 931         DPRINTK("========================================\n");
 932         DPRINTK("Display Information (EDID)\n");
 933         DPRINTK("========================================\n");
 934         DPRINTK("   EDID Version %d.%d\n", (int) specs->version,
 935                (int) specs->revision);
 936
 937         parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);
 938
 939         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 940         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
 941                 if (edid_is_serial_block(block)) {
 942                         copy_string(block, specs->serial_no);
 943                         DPRINTK("   Serial Number: %s\n", specs->serial_no);
 944                 } else if (edid_is_ascii_block(block)) {
 945                         copy_string(block, specs->ascii);
 946                         DPRINTK("   ASCII Block: %s\n", specs->ascii);
 947                 } else if (edid_is_monitor_block(block)) {
 948                         copy_string(block, specs->monitor);
 949                         DPRINTK("   Monitor Name: %s\n", specs->monitor);
 950                 }
 951         }
 952
 953         DPRINTK("   Display Characteristics:\n");
 954         get_monspecs(edid, specs);
 955
 956         specs->modedb = fb_create_modedb(edid, &specs->modedb_len);
 957
 958         /*
 959          * Workaround for buggy EDIDs that sets that the first
 960          * detailed timing is preferred but has not detailed
 961          * timing specified
 962          */
 963         for (i = 0; i < specs->modedb_len; i++) {
 964                 if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {
 965                         found = 1;
 966                         break;
 967                 }
 968         }
 969
 970         if (!found)
 971                 specs->misc &= ~FB_MISC_1ST_DETAIL;
 972
 973         DPRINTK("========================================\n");
 974 }
 975
 976 void fb_edid_add_monspecs(unsigned char *edid, struct fb_monspecs *specs)
 977 {
 978         unsigned char *block;
 979         unsigned char *dtd_block;
 980         struct fb_videomode *mode, *m;
 981         int num = 0, i, first = 1;
 982
 983         if (edid == NULL)
 984                 return;
 985
 986         if (!edid_checksum(edid))
 987                 return;
 988
 989         if (edid[0] != 0x2)
 990                 return;
 991
 992         mode = kzalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
 993         if (mode == NULL)
 994                 return;
 995
 996         block = edid + 0x4;
 997         dtd_block = edid + edid[0x2];
 998
 999         DPRINTK("  Short Video Modes\n");
1000         while (block < dtd_block) {
1001                 unsigned tag = block[0] >> 5;
1002                 unsigned len = block[0] & 0x1f;
1003
1004                 block++;
1005                 if (dtd_block - block < len)
1006                         break;
1007
1008                 if (tag == 0x2) {
1009                         for (i = 0; i < len; i++) {
1010                                 unsigned m = block[i];
1011                                 if (m > 0 && m < CEA_MODEDB_SIZE) {
1012                                         memcpy(&mode[num], &cea_modes[m],
1013                                                sizeof(mode[num]));
1014                                         DPRINTK("  %d: %dx%d @ %d\n", m,
1015                                                 cea_modes[m].xres, cea_modes[m].yres,
1016                                                 cea_modes[m].refresh);
1017
1018                                         num++;
1019                                 }
1020                         }
1021                 } else if (tag == 0x3) {
1022                         if (len >= 3) {
1023                                 u32 ieee_reg = block[0] | (block[1] << 8) |
1024                                         (block[2] << 16);
1025                                 if (ieee_reg == 0x000c03)
1026                                         specs->misc |= FB_MISC_HDMI;
1027                         }
1028                 }
1029
1030                 block += len;
1031         }
1032
1033         DPRINTK("  Extended Detailed Timings\n");
1034
1035         for (i = 0; i < (128 - edid[0x2]) / DETAILED_TIMING_DESCRIPTION_SIZE;
1036              i++, dtd_block += DETAILED_TIMING_DESCRIPTION_SIZE) {
1037                 if (!(dtd_block[0] == 0x00 && dtd_block[1] == 0x00)) {
1038                         get_detailed_timing(dtd_block, &mode[num]);
1039                         if (first) {
1040                                 mode[num].flag |= FB_MODE_IS_FIRST;
1041                                 first = 0;
1042                         }
1043                         num++;
1044                 }
1045         }
1046
1047         /* Yikes, EDID data is totally useless */
1048         if (!num) {
1049                 kfree(mode);
1050                 return;
1051         }
1052
1053         m = kzalloc((specs->modedb_len + num) *
1054                        sizeof(struct fb_videomode), GFP_KERNEL);
1055
1056         if (!m) {
1057                 kfree(mode);
1058                 return;
1059         }
1060
1061         memmove(m, specs->modedb, specs->modedb_len * sizeof(struct fb_videomode));
1062         memmove(m + specs->modedb_len, mode, num * sizeof(struct fb_videomode));
1063         kfree(mode);
1064         kfree(specs->modedb);
1065         specs->modedb = m;
1066         specs->modedb_len = specs->modedb_len + num;
1067 }
1068
1069 /*
1070  * VESA Generalized Timing Formula (GTF)
1071  */
1072
1073 #define FLYBACK                     550
1074 #define V_FRONTPORCH                1
1075 #define H_OFFSET                    40
1076 #define H_SCALEFACTOR               20
1077 #define H_BLANKSCALE                128
1078 #define H_GRADIENT                  600
1079 #define C_VAL                       30
1080 #define M_VAL                       300
1081
1082 struct __fb_timings {
1083         u32 dclk;
1084         u32 hfreq;
1085         u32 vfreq;
1086         u32 hactive;
1087         u32 vactive;
1088         u32 hblank;
1089         u32 vblank;
1090         u32 htotal;
1091         u32 vtotal;
1092 };
1093
1094 /**
1095  * fb_get_vblank - get vertical blank time
1096  * @hfreq: horizontal freq
1097  *
1098  * DESCRIPTION:
1099  * vblank = right_margin + vsync_len + left_margin
1100  *
1101  *    given: right_margin = 1 (V_FRONTPORCH)
1102  *           vsync_len    = 3
1103  *           flyback      = 550
1104  *
1105  *                          flyback * hfreq
1106  *           left_margin  = --------------- - vsync_len
1107  *                           1000000
1108  */
1109 static u32 fb_get_vblank(u32 hfreq)
1110 {
1111         u32 vblank;
1112
1113         vblank = (hfreq * FLYBACK)/1000;
1114         vblank = (vblank + 500)/1000;
1115         return (vblank + V_FRONTPORCH);
1116 }
1117
1118 /**
1119  * fb_get_hblank_by_freq - get horizontal blank time given hfreq
1120  * @hfreq: horizontal freq
1121  * @xres: horizontal resolution in pixels
1122  *
1123  * DESCRIPTION:
1124  *
1125  *           xres * duty_cycle
1126  * hblank = ------------------
1127  *           100 - duty_cycle
1128  *
1129  * duty cycle = percent of htotal assigned to inactive display
1130  * duty cycle = C - (M/Hfreq)
1131  *
1132  * where: C = ((offset - scale factor) * blank_scale)
1133  *            -------------------------------------- + scale factor
1134  *                        256
1135  *        M = blank_scale * gradient
1136  *
1137  */
1138 static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
1139 {
1140         u32 c_val, m_val, duty_cycle, hblank;
1141
1142         c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 +
1143                  H_SCALEFACTOR) * 1000;
1144         m_val = (H_BLANKSCALE * H_GRADIENT)/256;
1145         m_val = (m_val * 1000000)/hfreq;
1146         duty_cycle = c_val - m_val;
1147         hblank = (xres * duty_cycle)/(100000 - duty_cycle);
1148         return (hblank);
1149 }
1150
1151 /**
1152  * fb_get_hblank_by_dclk - get horizontal blank time given pixelclock
1153  * @dclk: pixelclock in Hz
1154  * @xres: horizontal resolution in pixels
1155  *
1156  * DESCRIPTION:
1157  *
1158  *           xres * duty_cycle
1159  * hblank = ------------------
1160  *           100 - duty_cycle
1161  *
1162  * duty cycle = percent of htotal assigned to inactive display
1163  * duty cycle = C - (M * h_period)
1164  *
1165  * where: h_period = SQRT(100 - C + (0.4 * xres * M)/dclk) + C - 100
1166  *                   -----------------------------------------------
1167  *                                    2 * M
1168  *        M = 300;
1169  *        C = 30;
1170
1171  */
1172 static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)
1173 {
1174         u32 duty_cycle, h_period, hblank;
1175
1176         dclk /= 1000;
1177         h_period = 100 - C_VAL;
1178         h_period *= h_period;
1179         h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);
1180         h_period *= 10000;
1181
1182         h_period = int_sqrt(h_period);
1183         h_period -= (100 - C_VAL) * 100;
1184         h_period *= 1000;
1185         h_period /= 2 * M_VAL;
1186
1187         duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;
1188         hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;
1189         hblank &= ~15;
1190         return (hblank);
1191 }
1192
1193 /**
1194  * fb_get_hfreq - estimate hsync
1195  * @vfreq: vertical refresh rate
1196  * @yres: vertical resolution
1197  *
1198  * DESCRIPTION:
1199  *
1200  *          (yres + front_port) * vfreq * 1000000
1201  * hfreq = -------------------------------------
1202  *          (1000000 - (vfreq * FLYBACK)
1203  *
1204  */
1205
1206 static u32 fb_get_hfreq(u32 vfreq, u32 yres)
1207 {
1208         u32 divisor, hfreq;
1209
1210         divisor = (1000000 - (vfreq * FLYBACK))/1000;
1211         hfreq = (yres + V_FRONTPORCH) * vfreq  * 1000;
1212         return (hfreq/divisor);
1213 }
1214
1215 static void fb_timings_vfreq(struct __fb_timings *timings)
1216 {
1217         timings->hfreq = fb_get_hfreq(timings->vfreq, timings->vactive);
1218         timings->vblank = fb_get_vblank(timings->hfreq);
1219         timings->vtotal = timings->vactive + timings->vblank;
1220         timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1221                                                  timings->hactive);
1222         timings->htotal = timings->hactive + timings->hblank;
1223         timings->dclk = timings->htotal * timings->hfreq;
1224 }
1225
1226 static void fb_timings_hfreq(struct __fb_timings *timings)
1227 {
1228         timings->vblank = fb_get_vblank(timings->hfreq);
1229         timings->vtotal = timings->vactive + timings->vblank;
1230         timings->vfreq = timings->hfreq/timings->vtotal;
1231         timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1232                                                  timings->hactive);
1233         timings->htotal = timings->hactive + timings->hblank;
1234         timings->dclk = timings->htotal * timings->hfreq;
1235 }
1236
1237 static void fb_timings_dclk(struct __fb_timings *timings)
1238 {
1239         timings->hblank = fb_get_hblank_by_dclk(timings->dclk,
1240                                                 timings->hactive);
1241         timings->htotal = timings->hactive + timings->hblank;
1242         timings->hfreq = timings->dclk/timings->htotal;
1243         timings->vblank = fb_get_vblank(timings->hfreq);
1244         timings->vtotal = timings->vactive + timings->vblank;
1245         timings->vfreq = timings->hfreq/timings->vtotal;
1246 }
1247
1248 /*
1249  * fb_get_mode - calculates video mode using VESA GTF
1250  * @flags: if: 0 - maximize vertical refresh rate
1251  *             1 - vrefresh-driven calculation;
1252  *             2 - hscan-driven calculation;
1253  *             3 - pixelclock-driven calculation;
1254  * @val: depending on @flags, ignored, vrefresh, hsync or pixelclock
1255  * @var: pointer to fb_var_screeninfo
1256  * @info: pointer to fb_info
1257  *
1258  * DESCRIPTION:
1259  * Calculates video mode based on monitor specs using VESA GTF.
1260  * The GTF is best for VESA GTF compliant monitors but is
1261  * specifically formulated to work for older monitors as well.
1262  *
1263  * If @flag==0, the function will attempt to maximize the
1264  * refresh rate.  Otherwise, it will calculate timings based on
1265  * the flag and accompanying value.
1266  *
1267  * If FB_IGNOREMON bit is set in @flags, monitor specs will be
1268  * ignored and @var will be filled with the calculated timings.
1269  *
1270  * All calculations are based on the VESA GTF Spreadsheet
1271  * available at VESA's public ftp (http://www.vesa.org).
1272  *
1273  * NOTES:
1274  * The timings generated by the GTF will be different from VESA
1275  * DMT.  It might be a good idea to keep a table of standard
1276  * VESA modes as well.  The GTF may also not work for some displays,
1277  * such as, and especially, analog TV.
1278  *
1279  * REQUIRES:
1280  * A valid info->monspecs, otherwise 'safe numbers' will be used.
1281  */
1282 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)
1283 {
1284         struct __fb_timings *timings;
1285         u32 interlace = 1, dscan = 1;
1286         u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;
1287
1288
1289         timings = kzalloc(sizeof(struct __fb_timings), GFP_KERNEL);
1290
1291         if (!timings)
1292                 return -ENOMEM;
1293
1294         /*
1295          * If monspecs are invalid, use values that are enough
1296          * for 640x480@60
1297          */
1298         if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||
1299             !info->monspecs.dclkmax ||
1300             info->monspecs.hfmax < info->monspecs.hfmin ||
1301             info->monspecs.vfmax < info->monspecs.vfmin ||
1302             info->monspecs.dclkmax < info->monspecs.dclkmin) {
1303                 hfmin = 29000; hfmax = 30000;
1304                 vfmin = 60; vfmax = 60;
1305                 dclkmin = 0; dclkmax = 25000000;
1306         } else {
1307                 hfmin = info->monspecs.hfmin;
1308                 hfmax = info->monspecs.hfmax;
1309                 vfmin = info->monspecs.vfmin;
1310                 vfmax = info->monspecs.vfmax;
1311                 dclkmin = info->monspecs.dclkmin;
1312                 dclkmax = info->monspecs.dclkmax;
1313         }
1314
1315         timings->hactive = var->xres;
1316         timings->vactive = var->yres;
1317         if (var->vmode & FB_VMODE_INTERLACED) {
1318                 timings->vactive /= 2;
1319                 interlace = 2;
1320         }
1321         if (var->vmode & FB_VMODE_DOUBLE) {
1322                 timings->vactive *= 2;
1323                 dscan = 2;
1324         }
1325
1326         switch (flags & ~FB_IGNOREMON) {
1327         case FB_MAXTIMINGS: /* maximize refresh rate */
1328                 timings->hfreq = hfmax;
1329                 fb_timings_hfreq(timings);
1330                 if (timings->vfreq > vfmax) {
1331                         timings->vfreq = vfmax;
1332                         fb_timings_vfreq(timings);
1333                 }
1334                 if (timings->dclk > dclkmax) {
1335                         timings->dclk = dclkmax;
1336                         fb_timings_dclk(timings);
1337                 }
1338                 break;
1339         case FB_VSYNCTIMINGS: /* vrefresh driven */
1340                 timings->vfreq = val;
1341                 fb_timings_vfreq(timings);
1342                 break;
1343         case FB_HSYNCTIMINGS: /* hsync driven */
1344                 timings->hfreq = val;
1345                 fb_timings_hfreq(timings);
1346                 break;
1347         case FB_DCLKTIMINGS: /* pixelclock driven */
1348                 timings->dclk = PICOS2KHZ(val) * 1000;
1349                 fb_timings_dclk(timings);
1350                 break;
1351         default:
1352                 err = -EINVAL;
1353
1354         }
1355
1356         if (err || (!(flags & FB_IGNOREMON) &&
1357             (timings->vfreq < vfmin || timings->vfreq > vfmax ||
1358              timings->hfreq < hfmin || timings->hfreq > hfmax ||
1359              timings->dclk < dclkmin || timings->dclk > dclkmax))) {
1360                 err = -EINVAL;
1361         } else {
1362                 var->pixclock = KHZ2PICOS(timings->dclk/1000);
1363                 var->hsync_len = (timings->htotal * 8)/100;
1364                 var->right_margin = (timings->hblank/2) - var->hsync_len;
1365                 var->left_margin = timings->hblank - var->right_margin -
1366                         var->hsync_len;
1367                 var->vsync_len = (3 * interlace)/dscan;
1368                 var->lower_margin = (1 * interlace)/dscan;
1369                 var->upper_margin = (timings->vblank * interlace)/dscan -
1370                         (var->vsync_len + var->lower_margin);
1371         }
1372
1373         kfree(timings);
1374         return err;
1375 }
1376 #else
1377 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
1378 {
1379         return 1;
1380 }
1381 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1382 {
1383         specs = NULL;
1384 }
1385 void fb_destroy_modedb(struct fb_videomode *modedb)
1386 {
1387 }
1388 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
1389                 struct fb_info *info)
1390 {
1391         return -EINVAL;
1392 }
1393 #endif /* CONFIG_FB_MODE_HELPERS */
1394
1395 /*
1396  * fb_validate_mode - validates var against monitor capabilities
1397  * @var: pointer to fb_var_screeninfo
1398  * @info: pointer to fb_info
1399  *
1400  * DESCRIPTION:
1401  * Validates video mode against monitor capabilities specified in
1402  * info->monspecs.
1403  *
1404  * REQUIRES:
1405  * A valid info->monspecs.
1406  */
1407 int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
1408 {
1409         u32 hfreq, vfreq, htotal, vtotal, pixclock;
1410         u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
1411
1412         /*
1413          * If monspecs are invalid, use values that are enough
1414          * for 640x480@60
1415          */
1416         if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
1417             !info->monspecs.dclkmax ||
1418             info->monspecs.hfmax < info->monspecs.hfmin ||
1419             info->monspecs.vfmax < info->monspecs.vfmin ||
1420             info->monspecs.dclkmax < info->monspecs.dclkmin) {
1421                 hfmin = 29000; hfmax = 30000;
1422                 vfmin = 60; vfmax = 60;
1423                 dclkmin = 0; dclkmax = 25000000;
1424         } else {
1425                 hfmin = info->monspecs.hfmin;
1426                 hfmax = info->monspecs.hfmax;
1427                 vfmin = info->monspecs.vfmin;
1428                 vfmax = info->monspecs.vfmax;
1429                 dclkmin = info->monspecs.dclkmin;
1430                 dclkmax = info->monspecs.dclkmax;
1431         }
1432
1433         if (!var->pixclock)
1434                 return -EINVAL;
1435         pixclock = PICOS2KHZ(var->pixclock) * 1000;
1436
1437         htotal = var->xres + var->right_margin + var->hsync_len +
1438                 var->left_margin;
1439         vtotal = var->yres + var->lower_margin + var->vsync_len +
1440                 var->upper_margin;
1441
1442         if (var->vmode & FB_VMODE_INTERLACED)
1443                 vtotal /= 2;
1444         if (var->vmode & FB_VMODE_DOUBLE)
1445                 vtotal *= 2;
1446
1447         hfreq = pixclock/htotal;
1448         hfreq = (hfreq + 500) / 1000 * 1000;
1449
1450         vfreq = hfreq/vtotal;
1451
1452         return (vfreq < vfmin || vfreq > vfmax ||
1453                 hfreq < hfmin || hfreq > hfmax ||
1454                 pixclock < dclkmin || pixclock > dclkmax) ?
1455                 -EINVAL : 0;
1456 }
1457
1458 #if defined(CONFIG_FIRMWARE_EDID) && defined(CONFIG_X86)
1459
1460 /*
1461  * We need to ensure that the EDID block is only returned for
1462  * the primary graphics adapter.
1463  */
1464
1465 const unsigned char *fb_firmware_edid(struct device *device)
1466 {
1467         struct pci_dev *dev = NULL;
1468         struct resource *res = NULL;
1469         unsigned char *edid = NULL;
1470
1471         if (device)
1472                 dev = to_pci_dev(device);
1473
1474         if (dev)
1475                 res = &dev->resource[PCI_ROM_RESOURCE];
1476
1477         if (res && res->flags & IORESOURCE_ROM_SHADOW)
1478                 edid = edid_info.dummy;
1479
1480         return edid;
1481 }
1482 #else
1483 const unsigned char *fb_firmware_edid(struct device *device)
1484 {
1485         return NULL;
1486 }
1487 #endif
1488 EXPORT_SYMBOL(fb_firmware_edid);
1489
1490 EXPORT_SYMBOL(fb_parse_edid);
1491 EXPORT_SYMBOL(fb_edid_to_monspecs);
1492 EXPORT_SYMBOL(fb_get_mode);
1493 EXPORT_SYMBOL(fb_validate_mode);
1494 EXPORT_SYMBOL(fb_destroy_modedb);