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   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
  57struct broken_edid {
  58	u8  manufacturer[4];
  59	u32 model;
  60	u32 fix;
  61};
  62
  63static 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
  84static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
  85	0xff, 0xff, 0xff, 0x00
  86};
  87
  88static 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
  98static 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
 108static 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
 118static 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
 128static 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
 138static 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
 147static 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
 209static 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
 258static 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
 279static 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
 294static 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
 312static 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
 328static 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
 383static 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
 411static 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
 496static int get_std_timing(unsigned char *block, struct fb_videomode *mode,
 497		int ver, int rev)
 498{
 499	int xres, yres = 0, refresh, ratio, i;
 500
 501	xres = (block[0] + 31) * 8;
 502	if (xres <= 256)
 503		return 0;
 504
 505	ratio = (block[1] & 0xc0) >> 6;
 506	switch (ratio) {
 507	case 0:
 508		/* in EDID 1.3 the meaning of 0 changed to 16:10 (prior 1:1) */
 509		if (ver < 1 || (ver == 1 && rev < 3))
 510			yres = xres;
 511		else
 512			yres = (xres * 10)/16;
 513		break;
 514	case 1:
 515		yres = (xres * 3)/4;
 516		break;
 517	case 2:
 518		yres = (xres * 4)/5;
 519		break;
 520	case 3:
 521		yres = (xres * 9)/16;
 522		break;
 523	}
 524	refresh = (block[1] & 0x3f) + 60;
 525
 526	DPRINTK("      %dx%d@%dHz\n", xres, yres, refresh);
 527	for (i = 0; i < VESA_MODEDB_SIZE; i++) {
 528		if (vesa_modes[i].xres == xres &&
 529		    vesa_modes[i].yres == yres &&
 530		    vesa_modes[i].refresh == refresh) {
 531			*mode = vesa_modes[i];
 532			mode->flag |= FB_MODE_IS_STANDARD;
 533			return 1;
 534		}
 535	}
 536	calc_mode_timings(xres, yres, refresh, mode);
 537	return 1;
 538}
 539
 540static int get_dst_timing(unsigned char *block,
 541			  struct fb_videomode *mode, int ver, int rev)
 542{
 543	int j, num = 0;
 544
 545	for (j = 0; j < 6; j++, block += STD_TIMING_DESCRIPTION_SIZE)
 546		num += get_std_timing(block, &mode[num], ver, rev);
 547
 548	return num;
 549}
 550
 551static void get_detailed_timing(unsigned char *block,
 552				struct fb_videomode *mode)
 553{
 554	mode->xres = H_ACTIVE;
 555	mode->yres = V_ACTIVE;
 556	mode->pixclock = PIXEL_CLOCK;
 557	mode->pixclock /= 1000;
 558	mode->pixclock = KHZ2PICOS(mode->pixclock);
 559	mode->right_margin = H_SYNC_OFFSET;
 560	mode->left_margin = (H_ACTIVE + H_BLANKING) -
 561		(H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
 562	mode->upper_margin = V_BLANKING - V_SYNC_OFFSET -
 563		V_SYNC_WIDTH;
 564	mode->lower_margin = V_SYNC_OFFSET;
 565	mode->hsync_len = H_SYNC_WIDTH;
 566	mode->vsync_len = V_SYNC_WIDTH;
 567	if (HSYNC_POSITIVE)
 568		mode->sync |= FB_SYNC_HOR_HIGH_ACT;
 569	if (VSYNC_POSITIVE)
 570		mode->sync |= FB_SYNC_VERT_HIGH_ACT;
 571	mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *
 572				     (V_ACTIVE + V_BLANKING));
 573	if (INTERLACED) {
 574		mode->yres *= 2;
 575		mode->upper_margin *= 2;
 576		mode->lower_margin *= 2;
 577		mode->vsync_len *= 2;
 578		mode->vmode |= FB_VMODE_INTERLACED;
 579	}
 580	mode->flag = FB_MODE_IS_DETAILED;
 581
 582	DPRINTK("      %d MHz ",  PIXEL_CLOCK/1000000);
 583	DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET,
 584	       H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING);
 585	DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET,
 586	       V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING);
 587	DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-",
 588	       (VSYNC_POSITIVE) ? "+" : "-");
 589}
 590
 591/**
 592 * fb_create_modedb - create video mode database
 593 * @edid: EDID data
 594 * @dbsize: database size
 595 *
 596 * RETURNS: struct fb_videomode, @dbsize contains length of database
 597 *
 598 * DESCRIPTION:
 599 * This function builds a mode database using the contents of the EDID
 600 * data
 601 */
 602static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize)
 603{
 604	struct fb_videomode *mode, *m;
 605	unsigned char *block;
 606	int num = 0, i, first = 1;
 607	int ver, rev;
 608
 609	ver = edid[EDID_STRUCT_VERSION];
 610	rev = edid[EDID_STRUCT_REVISION];
 611
 612	mode = kzalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
 613	if (mode == NULL)
 614		return NULL;
 615
 616	if (edid == NULL || !edid_checksum(edid) ||
 617	    !edid_check_header(edid)) {
 618		kfree(mode);
 619		return NULL;
 620	}
 621
 622	*dbsize = 0;
 623
 624	DPRINTK("   Detailed Timings\n");
 625	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 626	for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
 627		if (!(block[0] == 0x00 && block[1] == 0x00)) {
 628			get_detailed_timing(block, &mode[num]);
 629			if (first) {
 630			        mode[num].flag |= FB_MODE_IS_FIRST;
 631				first = 0;
 632			}
 633			num++;
 634		}
 635	}
 636
 637	DPRINTK("   Supported VESA Modes\n");
 638	block = edid + ESTABLISHED_TIMING_1;
 639	num += get_est_timing(block, &mode[num]);
 640
 641	DPRINTK("   Standard Timings\n");
 642	block = edid + STD_TIMING_DESCRIPTIONS_START;
 643	for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE)
 644		num += get_std_timing(block, &mode[num], ver, rev);
 645
 646	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 647	for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
 648		if (block[0] == 0x00 && block[1] == 0x00 && block[3] == 0xfa)
 649			num += get_dst_timing(block + 5, &mode[num], ver, rev);
 650	}
 651
 652	/* Yikes, EDID data is totally useless */
 653	if (!num) {
 654		kfree(mode);
 655		return NULL;
 656	}
 657
 658	*dbsize = num;
 659	m = kmalloc(num * sizeof(struct fb_videomode), GFP_KERNEL);
 660	if (!m)
 661		return mode;
 662	memmove(m, mode, num * sizeof(struct fb_videomode));
 663	kfree(mode);
 664	return m;
 665}
 666
 667/**
 668 * fb_destroy_modedb - destroys mode database
 669 * @modedb: mode database to destroy
 670 *
 671 * DESCRIPTION:
 672 * Destroy mode database created by fb_create_modedb
 673 */
 674void fb_destroy_modedb(struct fb_videomode *modedb)
 675{
 676	kfree(modedb);
 677}
 678
 679static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
 680{
 681	int i, retval = 1;
 682	unsigned char *block;
 683
 684	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 685
 686	DPRINTK("      Monitor Operating Limits: ");
 687
 688	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
 689		if (edid_is_limits_block(block)) {
 690			specs->hfmin = H_MIN_RATE * 1000;
 691			specs->hfmax = H_MAX_RATE * 1000;
 692			specs->vfmin = V_MIN_RATE;
 693			specs->vfmax = V_MAX_RATE;
 694			specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;
 695			specs->gtf = (GTF_SUPPORT) ? 1 : 0;
 696			retval = 0;
 697			DPRINTK("From EDID\n");
 698			break;
 699		}
 700	}
 701
 702	/* estimate monitor limits based on modes supported */
 703	if (retval) {
 704		struct fb_videomode *modes, *mode;
 705		int num_modes, hz, hscan, pixclock;
 706		int vtotal, htotal;
 707
 708		modes = fb_create_modedb(edid, &num_modes);
 709		if (!modes) {
 710			DPRINTK("None Available\n");
 711			return 1;
 712		}
 713
 714		retval = 0;
 715		for (i = 0; i < num_modes; i++) {
 716			mode = &modes[i];
 717			pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
 718			htotal = mode->xres + mode->right_margin + mode->hsync_len
 719				+ mode->left_margin;
 720			vtotal = mode->yres + mode->lower_margin + mode->vsync_len
 721				+ mode->upper_margin;
 722
 723			if (mode->vmode & FB_VMODE_INTERLACED)
 724				vtotal /= 2;
 725
 726			if (mode->vmode & FB_VMODE_DOUBLE)
 727				vtotal *= 2;
 728
 729			hscan = (pixclock + htotal / 2) / htotal;
 730			hscan = (hscan + 500) / 1000 * 1000;
 731			hz = (hscan + vtotal / 2) / vtotal;
 732
 733			if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
 734				specs->dclkmax = pixclock;
 735
 736			if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
 737				specs->dclkmin = pixclock;
 738
 739			if (specs->hfmax == 0 || specs->hfmax < hscan)
 740				specs->hfmax = hscan;
 741
 742			if (specs->hfmin == 0 || specs->hfmin > hscan)
 743				specs->hfmin = hscan;
 744
 745			if (specs->vfmax == 0 || specs->vfmax < hz)
 746				specs->vfmax = hz;
 747
 748			if (specs->vfmin == 0 || specs->vfmin > hz)
 749				specs->vfmin = hz;
 750		}
 751		DPRINTK("Extrapolated\n");
 752		fb_destroy_modedb(modes);
 753	}
 754	DPRINTK("           H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",
 755		specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,
 756		specs->vfmax, specs->dclkmax/1000000);
 757	return retval;
 758}
 759
 760static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
 761{
 762	unsigned char c, *block;
 763
 764	block = edid + EDID_STRUCT_DISPLAY;
 765
 766	fb_get_monitor_limits(edid, specs);
 767
 768	c = block[0] & 0x80;
 769	specs->input = 0;
 770	if (c) {
 771		specs->input |= FB_DISP_DDI;
 772		DPRINTK("      Digital Display Input");
 773	} else {
 774		DPRINTK("      Analog Display Input: Input Voltage - ");
 775		switch ((block[0] & 0x60) >> 5) {
 776		case 0:
 777			DPRINTK("0.700V/0.300V");
 778			specs->input |= FB_DISP_ANA_700_300;
 779			break;
 780		case 1:
 781			DPRINTK("0.714V/0.286V");
 782			specs->input |= FB_DISP_ANA_714_286;
 783			break;
 784		case 2:
 785			DPRINTK("1.000V/0.400V");
 786			specs->input |= FB_DISP_ANA_1000_400;
 787			break;
 788		case 3:
 789			DPRINTK("0.700V/0.000V");
 790			specs->input |= FB_DISP_ANA_700_000;
 791			break;
 792		}
 793	}
 794	DPRINTK("\n      Sync: ");
 795	c = block[0] & 0x10;
 796	if (c)
 797		DPRINTK("      Configurable signal level\n");
 798	c = block[0] & 0x0f;
 799	specs->signal = 0;
 800	if (c & 0x10) {
 801		DPRINTK("Blank to Blank ");
 802		specs->signal |= FB_SIGNAL_BLANK_BLANK;
 803	}
 804	if (c & 0x08) {
 805		DPRINTK("Separate ");
 806		specs->signal |= FB_SIGNAL_SEPARATE;
 807	}
 808	if (c & 0x04) {
 809		DPRINTK("Composite ");
 810		specs->signal |= FB_SIGNAL_COMPOSITE;
 811	}
 812	if (c & 0x02) {
 813		DPRINTK("Sync on Green ");
 814		specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
 815	}
 816	if (c & 0x01) {
 817		DPRINTK("Serration on ");
 818		specs->signal |= FB_SIGNAL_SERRATION_ON;
 819	}
 820	DPRINTK("\n");
 821	specs->max_x = block[1];
 822	specs->max_y = block[2];
 823	DPRINTK("      Max H-size in cm: ");
 824	if (specs->max_x)
 825		DPRINTK("%d\n", specs->max_x);
 826	else
 827		DPRINTK("variable\n");
 828	DPRINTK("      Max V-size in cm: ");
 829	if (specs->max_y)
 830		DPRINTK("%d\n", specs->max_y);
 831	else
 832		DPRINTK("variable\n");
 833
 834	c = block[3];
 835	specs->gamma = c+100;
 836	DPRINTK("      Gamma: ");
 837	DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
 838
 839	get_dpms_capabilities(block[4], specs);
 840
 841	switch ((block[4] & 0x18) >> 3) {
 842	case 0:
 843		DPRINTK("      Monochrome/Grayscale\n");
 844		specs->input |= FB_DISP_MONO;
 845		break;
 846	case 1:
 847		DPRINTK("      RGB Color Display\n");
 848		specs->input |= FB_DISP_RGB;
 849		break;
 850	case 2:
 851		DPRINTK("      Non-RGB Multicolor Display\n");
 852		specs->input |= FB_DISP_MULTI;
 853		break;
 854	default:
 855		DPRINTK("      Unknown\n");
 856		specs->input |= FB_DISP_UNKNOWN;
 857		break;
 858	}
 859
 860	get_chroma(block, specs);
 861
 862	specs->misc = 0;
 863	c = block[4] & 0x7;
 864	if (c & 0x04) {
 865		DPRINTK("      Default color format is primary\n");
 866		specs->misc |= FB_MISC_PRIM_COLOR;
 867	}
 868	if (c & 0x02) {
 869		DPRINTK("      First DETAILED Timing is preferred\n");
 870		specs->misc |= FB_MISC_1ST_DETAIL;
 871	}
 872	if (c & 0x01) {
 873		printk("      Display is GTF capable\n");
 874		specs->gtf = 1;
 875	}
 876}
 877
 878int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
 879{
 880	int i;
 881	unsigned char *block;
 882
 883	if (edid == NULL || var == NULL)
 884		return 1;
 885
 886	if (!(edid_checksum(edid)))
 887		return 1;
 888
 889	if (!(edid_check_header(edid)))
 890		return 1;
 891
 892	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 893
 894	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
 895		if (edid_is_timing_block(block)) {
 896			var->xres = var->xres_virtual = H_ACTIVE;
 897			var->yres = var->yres_virtual = V_ACTIVE;
 898			var->height = var->width = 0;
 899			var->right_margin = H_SYNC_OFFSET;
 900			var->left_margin = (H_ACTIVE + H_BLANKING) -
 901				(H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
 902			var->upper_margin = V_BLANKING - V_SYNC_OFFSET -
 903				V_SYNC_WIDTH;
 904			var->lower_margin = V_SYNC_OFFSET;
 905			var->hsync_len = H_SYNC_WIDTH;
 906			var->vsync_len = V_SYNC_WIDTH;
 907			var->pixclock = PIXEL_CLOCK;
 908			var->pixclock /= 1000;
 909			var->pixclock = KHZ2PICOS(var->pixclock);
 910
 911			if (HSYNC_POSITIVE)
 912				var->sync |= FB_SYNC_HOR_HIGH_ACT;
 913			if (VSYNC_POSITIVE)
 914				var->sync |= FB_SYNC_VERT_HIGH_ACT;
 915			return 0;
 916		}
 917	}
 918	return 1;
 919}
 920
 921void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
 922{
 923	unsigned char *block;
 924	int i, found = 0;
 925
 926	if (edid == NULL)
 927		return;
 928
 929	if (!(edid_checksum(edid)))
 930		return;
 931
 932	if (!(edid_check_header(edid)))
 933		return;
 934
 935	memset(specs, 0, sizeof(struct fb_monspecs));
 936
 937	specs->version = edid[EDID_STRUCT_VERSION];
 938	specs->revision = edid[EDID_STRUCT_REVISION];
 939
 940	DPRINTK("========================================\n");
 941	DPRINTK("Display Information (EDID)\n");
 942	DPRINTK("========================================\n");
 943	DPRINTK("   EDID Version %d.%d\n", (int) specs->version,
 944	       (int) specs->revision);
 945
 946	parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);
 947
 948	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
 949	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
 950		if (edid_is_serial_block(block)) {
 951			copy_string(block, specs->serial_no);
 952			DPRINTK("   Serial Number: %s\n", specs->serial_no);
 953		} else if (edid_is_ascii_block(block)) {
 954			copy_string(block, specs->ascii);
 955			DPRINTK("   ASCII Block: %s\n", specs->ascii);
 956		} else if (edid_is_monitor_block(block)) {
 957			copy_string(block, specs->monitor);
 958			DPRINTK("   Monitor Name: %s\n", specs->monitor);
 959		}
 960	}
 961
 962	DPRINTK("   Display Characteristics:\n");
 963	get_monspecs(edid, specs);
 964
 965	specs->modedb = fb_create_modedb(edid, &specs->modedb_len);
 966
 967	/*
 968	 * Workaround for buggy EDIDs that sets that the first
 969	 * detailed timing is preferred but has not detailed
 970	 * timing specified
 971	 */
 972	for (i = 0; i < specs->modedb_len; i++) {
 973		if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {
 974			found = 1;
 975			break;
 976		}
 977	}
 978
 979	if (!found)
 980		specs->misc &= ~FB_MISC_1ST_DETAIL;
 981
 982	DPRINTK("========================================\n");
 983}
 984
 985/**
 986 * fb_edid_add_monspecs() - add monitor video modes from E-EDID data
 987 * @edid:	128 byte array with an E-EDID block
 988 * @spacs:	monitor specs to be extended
 989 */
 990void fb_edid_add_monspecs(unsigned char *edid, struct fb_monspecs *specs)
 991{
 992	unsigned char *block;
 993	struct fb_videomode *m;
 994	int num = 0, i;
 995	u8 svd[64], edt[(128 - 4) / DETAILED_TIMING_DESCRIPTION_SIZE];
 996	u8 pos = 4, svd_n = 0;
 997
 998	if (!edid)
 999		return;
1000
1001	if (!edid_checksum(edid))
1002		return;
1003
1004	if (edid[0] != 0x2 ||
1005	    edid[2] < 4 || edid[2] > 128 - DETAILED_TIMING_DESCRIPTION_SIZE)
1006		return;
1007
1008	DPRINTK("  Short Video Descriptors\n");
1009
1010	while (pos < edid[2]) {
1011		u8 len = edid[pos] & 0x1f, type = (edid[pos] >> 5) & 7;
1012		pr_debug("Data block %u of %u bytes\n", type, len);
1013		if (type == 2)
1014			for (i = pos; i < pos + len; i++) {
1015				u8 idx = edid[pos + i] & 0x7f;
1016				svd[svd_n++] = idx;
1017				pr_debug("N%sative mode #%d\n",
1018					 edid[pos + i] & 0x80 ? "" : "on-n", idx);
1019			}
1020		pos += len + 1;
1021	}
1022
1023	block = edid + edid[2];
1024
1025	DPRINTK("  Extended Detailed Timings\n");
1026
1027	for (i = 0; i < (128 - edid[2]) / DETAILED_TIMING_DESCRIPTION_SIZE;
1028	     i++, block += DETAILED_TIMING_DESCRIPTION_SIZE)
1029		if (PIXEL_CLOCK)
1030			edt[num++] = block - edid;
1031
1032	/* Yikes, EDID data is totally useless */
1033	if (!(num + svd_n))
1034		return;
1035
1036	m = kzalloc((specs->modedb_len + num + svd_n) *
1037		       sizeof(struct fb_videomode), GFP_KERNEL);
1038
1039	if (!m)
1040		return;
1041
1042	memcpy(m, specs->modedb, specs->modedb_len * sizeof(struct fb_videomode));
1043
1044	for (i = specs->modedb_len; i < specs->modedb_len + num; i++) {
1045		get_detailed_timing(edid + edt[i - specs->modedb_len], &m[i]);
1046		if (i == specs->modedb_len)
1047			m[i].flag |= FB_MODE_IS_FIRST;
1048		pr_debug("Adding %ux%u@%u\n", m[i].xres, m[i].yres, m[i].refresh);
1049	}
1050
1051	for (i = specs->modedb_len + num; i < specs->modedb_len + num + svd_n; i++) {
1052		int idx = svd[i - specs->modedb_len - num];
1053		if (!idx || idx > 63) {
1054			pr_warning("Reserved SVD code %d\n", idx);
1055		} else if (idx > ARRAY_SIZE(cea_modes) || !cea_modes[idx].xres) {
1056			pr_warning("Unimplemented SVD code %d\n", idx);
1057		} else {
1058			memcpy(&m[i], cea_modes + idx, sizeof(m[i]));
1059			pr_debug("Adding SVD #%d: %ux%u@%u\n", idx,
1060				 m[i].xres, m[i].yres, m[i].refresh);
1061		}
1062	}
1063
1064	kfree(specs->modedb);
1065	specs->modedb = m;
1066	specs->modedb_len = specs->modedb_len + num + svd_n;
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
1082struct __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 */
1109static 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 */
1138static 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 */
1172static 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
1206static 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
1215static 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
1226static 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
1237static 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 */
1282int 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
1377int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
1378{
1379	return 1;
1380}
1381void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1382{
1383	specs = NULL;
1384}
1385void fb_edid_add_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1386{
1387}
1388void fb_destroy_modedb(struct fb_videomode *modedb)
1389{
1390}
1391int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
1392		struct fb_info *info)
1393{
1394	return -EINVAL;
1395}
1396#endif /* CONFIG_FB_MODE_HELPERS */
1397
1398/*
1399 * fb_validate_mode - validates var against monitor capabilities
1400 * @var: pointer to fb_var_screeninfo
1401 * @info: pointer to fb_info
1402 *
1403 * DESCRIPTION:
1404 * Validates video mode against monitor capabilities specified in
1405 * info->monspecs.
1406 *
1407 * REQUIRES:
1408 * A valid info->monspecs.
1409 */
1410int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
1411{
1412	u32 hfreq, vfreq, htotal, vtotal, pixclock;
1413	u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
1414
1415	/*
1416	 * If monspecs are invalid, use values that are enough
1417	 * for 640x480@60
1418	 */
1419	if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
1420	    !info->monspecs.dclkmax ||
1421	    info->monspecs.hfmax < info->monspecs.hfmin ||
1422	    info->monspecs.vfmax < info->monspecs.vfmin ||
1423	    info->monspecs.dclkmax < info->monspecs.dclkmin) {
1424		hfmin = 29000; hfmax = 30000;
1425		vfmin = 60; vfmax = 60;
1426		dclkmin = 0; dclkmax = 25000000;
1427	} else {
1428		hfmin = info->monspecs.hfmin;
1429		hfmax = info->monspecs.hfmax;
1430		vfmin = info->monspecs.vfmin;
1431		vfmax = info->monspecs.vfmax;
1432		dclkmin = info->monspecs.dclkmin;
1433		dclkmax = info->monspecs.dclkmax;
1434	}
1435
1436	if (!var->pixclock)
1437		return -EINVAL;
1438	pixclock = PICOS2KHZ(var->pixclock) * 1000;
1439
1440	htotal = var->xres + var->right_margin + var->hsync_len +
1441		var->left_margin;
1442	vtotal = var->yres + var->lower_margin + var->vsync_len +
1443		var->upper_margin;
1444
1445	if (var->vmode & FB_VMODE_INTERLACED)
1446		vtotal /= 2;
1447	if (var->vmode & FB_VMODE_DOUBLE)
1448		vtotal *= 2;
1449
1450	hfreq = pixclock/htotal;
1451	hfreq = (hfreq + 500) / 1000 * 1000;
1452
1453	vfreq = hfreq/vtotal;
1454
1455	return (vfreq < vfmin || vfreq > vfmax ||
1456		hfreq < hfmin || hfreq > hfmax ||
1457		pixclock < dclkmin || pixclock > dclkmax) ?
1458		-EINVAL : 0;
1459}
1460
1461#if defined(CONFIG_FIRMWARE_EDID) && defined(CONFIG_X86)
1462
1463/*
1464 * We need to ensure that the EDID block is only returned for
1465 * the primary graphics adapter.
1466 */
1467
1468const unsigned char *fb_firmware_edid(struct device *device)
1469{
1470	struct pci_dev *dev = NULL;
1471	struct resource *res = NULL;
1472	unsigned char *edid = NULL;
1473
1474	if (device)
1475		dev = to_pci_dev(device);
1476
1477	if (dev)
1478		res = &dev->resource[PCI_ROM_RESOURCE];
1479
1480	if (res && res->flags & IORESOURCE_ROM_SHADOW)
1481		edid = edid_info.dummy;
1482
1483	return edid;
1484}
1485#else
1486const unsigned char *fb_firmware_edid(struct device *device)
1487{
1488	return NULL;
1489}
1490#endif
1491EXPORT_SYMBOL(fb_firmware_edid);
1492
1493EXPORT_SYMBOL(fb_parse_edid);
1494EXPORT_SYMBOL(fb_edid_to_monspecs);
1495EXPORT_SYMBOL(fb_edid_add_monspecs);
1496EXPORT_SYMBOL(fb_get_mode);
1497EXPORT_SYMBOL(fb_validate_mode);
1498EXPORT_SYMBOL(fb_destroy_modedb);