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1/*2 * linux/drivers/video/fbmon.c3 *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 Architecture11 *      Copyright (C) 1991-2002 SciTech Software, Inc. All rights reserved.12 *13 *   2. XFree86 4.3.0, interpret_edid.c14 *      Copyright 1998 by Egbert Eich <Egbert.Eich@Physik.TU-Darmstadt.DE>15 *16 *   3. John Fremlin <vii@users.sourceforge.net> and17 *      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 https://www.vesa.org23 *24 * This file is subject to the terms and conditions of the GNU General Public25 * License.  See the file COPYING in the main directory of this archive26 * 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#include <video/of_videomode.h>35#include <video/videomode.h>36#include "../edid.h"37 38/*39 * EDID parser40 */41 42#undef DEBUG  /* define this for verbose EDID parsing output */43 44#ifdef DEBUG45#define DPRINTK(fmt, args...) printk(fmt,## args)46#else47#define DPRINTK(fmt, args...) no_printk(fmt, ##args)48#endif49 50#define FBMON_FIX_HEADER  151#define FBMON_FIX_INPUT   252#define FBMON_FIX_TIMINGS 353 54#ifdef CONFIG_FB_MODE_HELPERS55struct broken_edid {56	u8  manufacturer[4];57	u32 model;58	u32 fix;59};60 61static const struct broken_edid brokendb[] = {62	/* DEC FR-PCXAV-YZ */63	{64		.manufacturer = "DEC",65		.model        = 0x073a,66		.fix          = FBMON_FIX_HEADER,67	},68	/* ViewSonic PF775a */69	{70		.manufacturer = "VSC",71		.model        = 0x5a44,72		.fix          = FBMON_FIX_INPUT,73	},74	/* Sharp UXGA? */75	{76		.manufacturer = "SHP",77		.model        = 0x138e,78		.fix          = FBMON_FIX_TIMINGS,79	},80};81 82static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,83	0xff, 0xff, 0xff, 0x0084};85 86static void copy_string(unsigned char *c, unsigned char *s)87{88  int i;89  c = c + 5;90  for (i = 0; (i < 13 && *c != 0x0A); i++)91    *(s++) = *(c++);92  *s = 0;93  while (i-- && (*--s == 0x20)) *s = 0;94}95 96static int edid_is_serial_block(unsigned char *block)97{98	if ((block[0] == 0x00) && (block[1] == 0x00) &&99	    (block[2] == 0x00) && (block[3] == 0xff) &&100	    (block[4] == 0x00))101		return 1;102	else103		return 0;104}105 106static int edid_is_ascii_block(unsigned char *block)107{108	if ((block[0] == 0x00) && (block[1] == 0x00) &&109	    (block[2] == 0x00) && (block[3] == 0xfe) &&110	    (block[4] == 0x00))111		return 1;112	else113		return 0;114}115 116static int edid_is_limits_block(unsigned char *block)117{118	if ((block[0] == 0x00) && (block[1] == 0x00) &&119	    (block[2] == 0x00) && (block[3] == 0xfd) &&120	    (block[4] == 0x00))121		return 1;122	else123		return 0;124}125 126static int edid_is_monitor_block(unsigned char *block)127{128	if ((block[0] == 0x00) && (block[1] == 0x00) &&129	    (block[2] == 0x00) && (block[3] == 0xfc) &&130	    (block[4] == 0x00))131		return 1;132	else133		return 0;134}135 136static int edid_is_timing_block(unsigned char *block)137{138	if ((block[0] != 0x00) || (block[1] != 0x00) ||139	    (block[2] != 0x00) || (block[4] != 0x00))140		return 1;141	else142		return 0;143}144 145static int check_edid(unsigned char *edid)146{147	unsigned char *block = edid + ID_MANUFACTURER_NAME, manufacturer[4];148	unsigned char *b;149	u32 model;150	int i, fix = 0, ret = 0;151 152	manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';153	manufacturer[1] = ((block[0] & 0x03) << 3) +154		((block[1] & 0xe0) >> 5) + '@';155	manufacturer[2] = (block[1] & 0x1f) + '@';156	manufacturer[3] = 0;157	model = block[2] + (block[3] << 8);158 159	for (i = 0; i < ARRAY_SIZE(brokendb); i++) {160		if (!strncmp(manufacturer, brokendb[i].manufacturer, 4) &&161			brokendb[i].model == model) {162			fix = brokendb[i].fix;163			break;164		}165	}166 167	switch (fix) {168	case FBMON_FIX_HEADER:169		for (i = 0; i < 8; i++) {170			if (edid[i] != edid_v1_header[i]) {171				ret = fix;172				break;173			}174		}175		break;176	case FBMON_FIX_INPUT:177		b = edid + EDID_STRUCT_DISPLAY;178		/* Only if display is GTF capable will179		   the input type be reset to analog */180		if (b[4] & 0x01 && b[0] & 0x80)181			ret = fix;182		break;183	case FBMON_FIX_TIMINGS:184		b = edid + DETAILED_TIMING_DESCRIPTIONS_START;185		ret = fix;186 187		for (i = 0; i < 4; i++) {188			if (edid_is_limits_block(b)) {189				ret = 0;190				break;191			}192 193			b += DETAILED_TIMING_DESCRIPTION_SIZE;194		}195 196		break;197	}198 199	if (ret)200		printk("fbmon: The EDID Block of "201		       "Manufacturer: %s Model: 0x%x is known to "202		       "be broken,\n",  manufacturer, model);203 204	return ret;205}206 207static void fix_edid(unsigned char *edid, int fix)208{209	int i;210	unsigned char *b, csum = 0;211 212	switch (fix) {213	case FBMON_FIX_HEADER:214		printk("fbmon: trying a header reconstruct\n");215		memcpy(edid, edid_v1_header, 8);216		break;217	case FBMON_FIX_INPUT:218		printk("fbmon: trying to fix input type\n");219		b = edid + EDID_STRUCT_DISPLAY;220		b[0] &= ~0x80;221		edid[127] += 0x80;222		break;223	case FBMON_FIX_TIMINGS:224		printk("fbmon: trying to fix monitor timings\n");225		b = edid + DETAILED_TIMING_DESCRIPTIONS_START;226		for (i = 0; i < 4; i++) {227			if (!(edid_is_serial_block(b) ||228			      edid_is_ascii_block(b) ||229			      edid_is_monitor_block(b) ||230			      edid_is_timing_block(b))) {231				b[0] = 0x00;232				b[1] = 0x00;233				b[2] = 0x00;234				b[3] = 0xfd;235				b[4] = 0x00;236				b[5] = 60;   /* vfmin */237				b[6] = 60;   /* vfmax */238				b[7] = 30;   /* hfmin */239				b[8] = 75;   /* hfmax */240				b[9] = 17;   /* pixclock - 170 MHz*/241				b[10] = 0;   /* GTF */242				break;243			}244 245			b += DETAILED_TIMING_DESCRIPTION_SIZE;246		}247 248		for (i = 0; i < EDID_LENGTH - 1; i++)249			csum += edid[i];250 251		edid[127] = 256 - csum;252		break;253	}254}255 256static int edid_checksum(unsigned char *edid)257{258	unsigned char csum = 0, all_null = 0;259	int i, err = 0, fix = check_edid(edid);260 261	if (fix)262		fix_edid(edid, fix);263 264	for (i = 0; i < EDID_LENGTH; i++) {265		csum += edid[i];266		all_null |= edid[i];267	}268 269	if (csum == 0x00 && all_null) {270		/* checksum passed, everything's good */271		err = 1;272	}273 274	return err;275}276 277static int edid_check_header(unsigned char *edid)278{279	int i, err = 1, fix = check_edid(edid);280 281	if (fix)282		fix_edid(edid, fix);283 284	for (i = 0; i < 8; i++) {285		if (edid[i] != edid_v1_header[i])286			err = 0;287	}288 289	return err;290}291 292static void parse_vendor_block(unsigned char *block, struct fb_monspecs *specs)293{294	specs->manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';295	specs->manufacturer[1] = ((block[0] & 0x03) << 3) +296		((block[1] & 0xe0) >> 5) + '@';297	specs->manufacturer[2] = (block[1] & 0x1f) + '@';298	specs->manufacturer[3] = 0;299	specs->model = block[2] + (block[3] << 8);300	specs->serial = block[4] + (block[5] << 8) +301	       (block[6] << 16) + (block[7] << 24);302	specs->year = block[9] + 1990;303	specs->week = block[8];304	DPRINTK("   Manufacturer: %s\n", specs->manufacturer);305	DPRINTK("   Model: %x\n", specs->model);306	DPRINTK("   Serial#: %u\n", specs->serial);307	DPRINTK("   Year: %u Week %u\n", specs->year, specs->week);308}309 310static void get_dpms_capabilities(unsigned char flags,311				  struct fb_monspecs *specs)312{313	specs->dpms = 0;314	if (flags & DPMS_ACTIVE_OFF)315		specs->dpms |= FB_DPMS_ACTIVE_OFF;316	if (flags & DPMS_SUSPEND)317		specs->dpms |= FB_DPMS_SUSPEND;318	if (flags & DPMS_STANDBY)319		specs->dpms |= FB_DPMS_STANDBY;320	DPRINTK("      DPMS: Active %s, Suspend %s, Standby %s\n",321	       (flags & DPMS_ACTIVE_OFF) ? "yes" : "no",322	       (flags & DPMS_SUSPEND)    ? "yes" : "no",323	       (flags & DPMS_STANDBY)    ? "yes" : "no");324}325 326static void get_chroma(unsigned char *block, struct fb_monspecs *specs)327{328	int tmp;329 330	DPRINTK("      Chroma\n");331	/* Chromaticity data */332	tmp = ((block[5] & (3 << 6)) >> 6) | (block[0x7] << 2);333	tmp *= 1000;334	tmp += 512;335	specs->chroma.redx = tmp/1024;336	DPRINTK("         RedX:     0.%03d ", specs->chroma.redx);337 338	tmp = ((block[5] & (3 << 4)) >> 4) | (block[0x8] << 2);339	tmp *= 1000;340	tmp += 512;341	specs->chroma.redy = tmp/1024;342	DPRINTK("RedY:     0.%03d\n", specs->chroma.redy);343 344	tmp = ((block[5] & (3 << 2)) >> 2) | (block[0x9] << 2);345	tmp *= 1000;346	tmp += 512;347	specs->chroma.greenx = tmp/1024;348	DPRINTK("         GreenX:   0.%03d ", specs->chroma.greenx);349 350	tmp = (block[5] & 3) | (block[0xa] << 2);351	tmp *= 1000;352	tmp += 512;353	specs->chroma.greeny = tmp/1024;354	DPRINTK("GreenY:   0.%03d\n", specs->chroma.greeny);355 356	tmp = ((block[6] & (3 << 6)) >> 6) | (block[0xb] << 2);357	tmp *= 1000;358	tmp += 512;359	specs->chroma.bluex = tmp/1024;360	DPRINTK("         BlueX:    0.%03d ", specs->chroma.bluex);361 362	tmp = ((block[6] & (3 << 4)) >> 4) | (block[0xc] << 2);363	tmp *= 1000;364	tmp += 512;365	specs->chroma.bluey = tmp/1024;366	DPRINTK("BlueY:    0.%03d\n", specs->chroma.bluey);367 368	tmp = ((block[6] & (3 << 2)) >> 2) | (block[0xd] << 2);369	tmp *= 1000;370	tmp += 512;371	specs->chroma.whitex = tmp/1024;372	DPRINTK("         WhiteX:   0.%03d ", specs->chroma.whitex);373 374	tmp = (block[6] & 3) | (block[0xe] << 2);375	tmp *= 1000;376	tmp += 512;377	specs->chroma.whitey = tmp/1024;378	DPRINTK("WhiteY:   0.%03d\n", specs->chroma.whitey);379}380 381static void calc_mode_timings(int xres, int yres, int refresh,382			      struct fb_videomode *mode)383{384	struct fb_var_screeninfo *var;385 386	var = kzalloc(sizeof(struct fb_var_screeninfo), GFP_KERNEL);387 388	if (var) {389		var->xres = xres;390		var->yres = yres;391		fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON,392			    refresh, var, NULL);393		mode->xres = xres;394		mode->yres = yres;395		mode->pixclock = var->pixclock;396		mode->refresh = refresh;397		mode->left_margin = var->left_margin;398		mode->right_margin = var->right_margin;399		mode->upper_margin = var->upper_margin;400		mode->lower_margin = var->lower_margin;401		mode->hsync_len = var->hsync_len;402		mode->vsync_len = var->vsync_len;403		mode->vmode = 0;404		mode->sync = 0;405		kfree(var);406	}407}408 409static int get_est_timing(unsigned char *block, struct fb_videomode *mode)410{411	int num = 0;412	unsigned char c;413 414	c = block[0];415	if (c&0x80) {416		calc_mode_timings(720, 400, 70, &mode[num]);417		mode[num++].flag = FB_MODE_IS_CALCULATED;418		DPRINTK("      720x400@70Hz\n");419	}420	if (c&0x40) {421		calc_mode_timings(720, 400, 88, &mode[num]);422		mode[num++].flag = FB_MODE_IS_CALCULATED;423		DPRINTK("      720x400@88Hz\n");424	}425	if (c&0x20) {426		mode[num++] = vesa_modes[3];427		DPRINTK("      640x480@60Hz\n");428	}429	if (c&0x10) {430		calc_mode_timings(640, 480, 67, &mode[num]);431		mode[num++].flag = FB_MODE_IS_CALCULATED;432		DPRINTK("      640x480@67Hz\n");433	}434	if (c&0x08) {435		mode[num++] = vesa_modes[4];436		DPRINTK("      640x480@72Hz\n");437	}438	if (c&0x04) {439		mode[num++] = vesa_modes[5];440		DPRINTK("      640x480@75Hz\n");441	}442	if (c&0x02) {443		mode[num++] = vesa_modes[7];444		DPRINTK("      800x600@56Hz\n");445	}446	if (c&0x01) {447		mode[num++] = vesa_modes[8];448		DPRINTK("      800x600@60Hz\n");449	}450 451	c = block[1];452	if (c&0x80) {453		mode[num++] = vesa_modes[9];454		DPRINTK("      800x600@72Hz\n");455	}456	if (c&0x40) {457		mode[num++] = vesa_modes[10];458		DPRINTK("      800x600@75Hz\n");459	}460	if (c&0x20) {461		calc_mode_timings(832, 624, 75, &mode[num]);462		mode[num++].flag = FB_MODE_IS_CALCULATED;463		DPRINTK("      832x624@75Hz\n");464	}465	if (c&0x10) {466		mode[num++] = vesa_modes[12];467		DPRINTK("      1024x768@87Hz Interlaced\n");468	}469	if (c&0x08) {470		mode[num++] = vesa_modes[13];471		DPRINTK("      1024x768@60Hz\n");472	}473	if (c&0x04) {474		mode[num++] = vesa_modes[14];475		DPRINTK("      1024x768@70Hz\n");476	}477	if (c&0x02) {478		mode[num++] = vesa_modes[15];479		DPRINTK("      1024x768@75Hz\n");480	}481	if (c&0x01) {482		mode[num++] = vesa_modes[21];483		DPRINTK("      1280x1024@75Hz\n");484	}485	c = block[2];486	if (c&0x80) {487		mode[num++] = vesa_modes[17];488		DPRINTK("      1152x870@75Hz\n");489	}490	DPRINTK("      Manufacturer's mask: %x\n",c&0x7F);491	return num;492}493 494static int get_std_timing(unsigned char *block, struct fb_videomode *mode,495			  int ver, int rev, const struct fb_monspecs *specs)496{497	int i;498 499	for (i = 0; i < DMT_SIZE; i++) {500		u32 std_2byte_code = block[0] << 8 | block[1];501		if (std_2byte_code == dmt_modes[i].std_2byte_code)502			break;503	}504 505	if (i < DMT_SIZE && dmt_modes[i].mode) {506		/* DMT mode found */507		*mode = *dmt_modes[i].mode;508		mode->flag |= FB_MODE_IS_STANDARD;509		DPRINTK("        DMT id=%d\n", dmt_modes[i].dmt_id);510 511	} else {512		int xres, yres = 0, refresh, ratio;513 514		xres = (block[0] + 31) * 8;515		if (xres <= 256)516			return 0;517 518		ratio = (block[1] & 0xc0) >> 6;519		switch (ratio) {520		case 0:521			/* in EDID 1.3 the meaning of 0 changed to 16:10 (prior 1:1) */522			if (ver < 1 || (ver == 1 && rev < 3))523				yres = xres;524			else525				yres = (xres * 10)/16;526			break;527		case 1:528			yres = (xres * 3)/4;529			break;530		case 2:531			yres = (xres * 4)/5;532			break;533		case 3:534			yres = (xres * 9)/16;535			break;536		}537		refresh = (block[1] & 0x3f) + 60;538		DPRINTK("      %dx%d@%dHz\n", xres, yres, refresh);539 540		calc_mode_timings(xres, yres, refresh, mode);541	}542 543	/* Check the mode we got is within valid spec of the monitor */544	if (specs && specs->dclkmax545	    && PICOS2KHZ(mode->pixclock) * 1000 > specs->dclkmax) {546		DPRINTK("        mode exceed max DCLK\n");547		return 0;548	}549 550	return 1;551}552 553static int get_dst_timing(unsigned char *block, struct fb_videomode *mode,554			  int ver, int rev, const struct fb_monspecs *specs)555{556	int j, num = 0;557 558	for (j = 0; j < 6; j++, block += STD_TIMING_DESCRIPTION_SIZE)559		num += get_std_timing(block, &mode[num], ver, rev, specs);560 561	return num;562}563 564static void get_detailed_timing(unsigned char *block,565				struct fb_videomode *mode)566{567	mode->xres = H_ACTIVE;568	mode->yres = V_ACTIVE;569	mode->pixclock = PIXEL_CLOCK;570	mode->pixclock /= 1000;571	mode->pixclock = KHZ2PICOS(mode->pixclock);572	mode->right_margin = H_SYNC_OFFSET;573	mode->left_margin = (H_ACTIVE + H_BLANKING) -574		(H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);575	mode->upper_margin = V_BLANKING - V_SYNC_OFFSET -576		V_SYNC_WIDTH;577	mode->lower_margin = V_SYNC_OFFSET;578	mode->hsync_len = H_SYNC_WIDTH;579	mode->vsync_len = V_SYNC_WIDTH;580	if (HSYNC_POSITIVE)581		mode->sync |= FB_SYNC_HOR_HIGH_ACT;582	if (VSYNC_POSITIVE)583		mode->sync |= FB_SYNC_VERT_HIGH_ACT;584	mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *585				     (V_ACTIVE + V_BLANKING));586	if (INTERLACED) {587		mode->yres *= 2;588		mode->upper_margin *= 2;589		mode->lower_margin *= 2;590		mode->vsync_len *= 2;591		mode->vmode |= FB_VMODE_INTERLACED;592	}593	mode->flag = FB_MODE_IS_DETAILED;594 595	DPRINTK("      %d MHz ",  PIXEL_CLOCK/1000000);596	DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET,597	       H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING);598	DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET,599	       V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING);600	DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-",601	       (VSYNC_POSITIVE) ? "+" : "-");602}603 604/**605 * fb_create_modedb - create video mode database606 * @edid: EDID data607 * @dbsize: database size608 * @specs: monitor specifications, may be NULL609 *610 * RETURNS: struct fb_videomode, @dbsize contains length of database611 *612 * DESCRIPTION:613 * This function builds a mode database using the contents of the EDID614 * data615 */616static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize,617					     const struct fb_monspecs *specs)618{619	struct fb_videomode *mode, *m;620	unsigned char *block;621	int num = 0, i, first = 1;622	int ver, rev;623 624	mode = kcalloc(50, sizeof(struct fb_videomode), GFP_KERNEL);625	if (mode == NULL)626		return NULL;627 628	if (edid == NULL || !edid_checksum(edid) ||629	    !edid_check_header(edid)) {630		kfree(mode);631		return NULL;632	}633 634	ver = edid[EDID_STRUCT_VERSION];635	rev = edid[EDID_STRUCT_REVISION];636 637	*dbsize = 0;638 639	DPRINTK("   Detailed Timings\n");640	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;641	for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {642		if (!(block[0] == 0x00 && block[1] == 0x00)) {643			get_detailed_timing(block, &mode[num]);644			if (first) {645			        mode[num].flag |= FB_MODE_IS_FIRST;646				first = 0;647			}648			num++;649		}650	}651 652	DPRINTK("   Supported VESA Modes\n");653	block = edid + ESTABLISHED_TIMING_1;654	num += get_est_timing(block, &mode[num]);655 656	DPRINTK("   Standard Timings\n");657	block = edid + STD_TIMING_DESCRIPTIONS_START;658	for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE)659		num += get_std_timing(block, &mode[num], ver, rev, specs);660 661	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;662	for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {663		if (block[0] == 0x00 && block[1] == 0x00 && block[3] == 0xfa)664			num += get_dst_timing(block + 5, &mode[num],665					      ver, rev, specs);666	}667 668	/* Yikes, EDID data is totally useless */669	if (!num) {670		kfree(mode);671		return NULL;672	}673 674	*dbsize = num;675	m = kmalloc_array(num, sizeof(struct fb_videomode), GFP_KERNEL);676	if (!m)677		return mode;678	memmove(m, mode, num * sizeof(struct fb_videomode));679	kfree(mode);680	return m;681}682 683/**684 * fb_destroy_modedb - destroys mode database685 * @modedb: mode database to destroy686 *687 * DESCRIPTION:688 * Destroy mode database created by fb_create_modedb689 */690void fb_destroy_modedb(struct fb_videomode *modedb)691{692	kfree(modedb);693}694 695static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)696{697	int i, retval = 1;698	unsigned char *block;699 700	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;701 702	DPRINTK("      Monitor Operating Limits: ");703 704	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {705		if (edid_is_limits_block(block)) {706			specs->hfmin = H_MIN_RATE * 1000;707			specs->hfmax = H_MAX_RATE * 1000;708			specs->vfmin = V_MIN_RATE;709			specs->vfmax = V_MAX_RATE;710			specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;711			specs->gtf = (GTF_SUPPORT) ? 1 : 0;712			retval = 0;713			DPRINTK("From EDID\n");714			break;715		}716	}717 718	/* estimate monitor limits based on modes supported */719	if (retval) {720		struct fb_videomode *modes, *mode;721		int num_modes, hz, hscan, pixclock;722		int vtotal, htotal;723 724		modes = fb_create_modedb(edid, &num_modes, specs);725		if (!modes) {726			DPRINTK("None Available\n");727			return 1;728		}729 730		retval = 0;731		for (i = 0; i < num_modes; i++) {732			mode = &modes[i];733			pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;734			htotal = mode->xres + mode->right_margin + mode->hsync_len735				+ mode->left_margin;736			vtotal = mode->yres + mode->lower_margin + mode->vsync_len737				+ mode->upper_margin;738 739			if (mode->vmode & FB_VMODE_INTERLACED)740				vtotal /= 2;741 742			if (mode->vmode & FB_VMODE_DOUBLE)743				vtotal *= 2;744 745			hscan = (pixclock + htotal / 2) / htotal;746			hscan = (hscan + 500) / 1000 * 1000;747			hz = (hscan + vtotal / 2) / vtotal;748 749			if (specs->dclkmax == 0 || specs->dclkmax < pixclock)750				specs->dclkmax = pixclock;751 752			if (specs->dclkmin == 0 || specs->dclkmin > pixclock)753				specs->dclkmin = pixclock;754 755			if (specs->hfmax == 0 || specs->hfmax < hscan)756				specs->hfmax = hscan;757 758			if (specs->hfmin == 0 || specs->hfmin > hscan)759				specs->hfmin = hscan;760 761			if (specs->vfmax == 0 || specs->vfmax < hz)762				specs->vfmax = hz;763 764			if (specs->vfmin == 0 || specs->vfmin > hz)765				specs->vfmin = hz;766		}767		DPRINTK("Extrapolated\n");768		fb_destroy_modedb(modes);769	}770	DPRINTK("           H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",771		specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,772		specs->vfmax, specs->dclkmax/1000000);773	return retval;774}775 776static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)777{778	unsigned char c, *block;779 780	block = edid + EDID_STRUCT_DISPLAY;781 782	fb_get_monitor_limits(edid, specs);783 784	c = block[0] & 0x80;785	specs->input = 0;786	if (c) {787		specs->input |= FB_DISP_DDI;788		DPRINTK("      Digital Display Input");789	} else {790		DPRINTK("      Analog Display Input: Input Voltage - ");791		switch ((block[0] & 0x60) >> 5) {792		case 0:793			DPRINTK("0.700V/0.300V");794			specs->input |= FB_DISP_ANA_700_300;795			break;796		case 1:797			DPRINTK("0.714V/0.286V");798			specs->input |= FB_DISP_ANA_714_286;799			break;800		case 2:801			DPRINTK("1.000V/0.400V");802			specs->input |= FB_DISP_ANA_1000_400;803			break;804		case 3:805			DPRINTK("0.700V/0.000V");806			specs->input |= FB_DISP_ANA_700_000;807			break;808		}809	}810	DPRINTK("\n      Sync: ");811	c = block[0] & 0x10;812	if (c)813		DPRINTK("      Configurable signal level\n");814	c = block[0] & 0x0f;815	specs->signal = 0;816	if (c & 0x10) {817		DPRINTK("Blank to Blank ");818		specs->signal |= FB_SIGNAL_BLANK_BLANK;819	}820	if (c & 0x08) {821		DPRINTK("Separate ");822		specs->signal |= FB_SIGNAL_SEPARATE;823	}824	if (c & 0x04) {825		DPRINTK("Composite ");826		specs->signal |= FB_SIGNAL_COMPOSITE;827	}828	if (c & 0x02) {829		DPRINTK("Sync on Green ");830		specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;831	}832	if (c & 0x01) {833		DPRINTK("Serration on ");834		specs->signal |= FB_SIGNAL_SERRATION_ON;835	}836	DPRINTK("\n");837	specs->max_x = block[1];838	specs->max_y = block[2];839	DPRINTK("      Max H-size in cm: ");840	if (specs->max_x)841		DPRINTK("%d\n", specs->max_x);842	else843		DPRINTK("variable\n");844	DPRINTK("      Max V-size in cm: ");845	if (specs->max_y)846		DPRINTK("%d\n", specs->max_y);847	else848		DPRINTK("variable\n");849 850	c = block[3];851	specs->gamma = c+100;852	DPRINTK("      Gamma: ");853	DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);854 855	get_dpms_capabilities(block[4], specs);856 857	switch ((block[4] & 0x18) >> 3) {858	case 0:859		DPRINTK("      Monochrome/Grayscale\n");860		specs->input |= FB_DISP_MONO;861		break;862	case 1:863		DPRINTK("      RGB Color Display\n");864		specs->input |= FB_DISP_RGB;865		break;866	case 2:867		DPRINTK("      Non-RGB Multicolor Display\n");868		specs->input |= FB_DISP_MULTI;869		break;870	default:871		DPRINTK("      Unknown\n");872		specs->input |= FB_DISP_UNKNOWN;873		break;874	}875 876	get_chroma(block, specs);877 878	specs->misc = 0;879	c = block[4] & 0x7;880	if (c & 0x04) {881		DPRINTK("      Default color format is primary\n");882		specs->misc |= FB_MISC_PRIM_COLOR;883	}884	if (c & 0x02) {885		DPRINTK("      First DETAILED Timing is preferred\n");886		specs->misc |= FB_MISC_1ST_DETAIL;887	}888	if (c & 0x01) {889		printk("      Display is GTF capable\n");890		specs->gtf = 1;891	}892}893 894int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)895{896	int i;897	unsigned char *block;898 899	if (edid == NULL || var == NULL)900		return 1;901 902	if (!(edid_checksum(edid)))903		return 1;904 905	if (!(edid_check_header(edid)))906		return 1;907 908	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;909 910	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {911		if (edid_is_timing_block(block)) {912			var->xres = var->xres_virtual = H_ACTIVE;913			var->yres = var->yres_virtual = V_ACTIVE;914			var->height = var->width = 0;915			var->right_margin = H_SYNC_OFFSET;916			var->left_margin = (H_ACTIVE + H_BLANKING) -917				(H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);918			var->upper_margin = V_BLANKING - V_SYNC_OFFSET -919				V_SYNC_WIDTH;920			var->lower_margin = V_SYNC_OFFSET;921			var->hsync_len = H_SYNC_WIDTH;922			var->vsync_len = V_SYNC_WIDTH;923			var->pixclock = PIXEL_CLOCK;924			var->pixclock /= 1000;925			var->pixclock = KHZ2PICOS(var->pixclock);926 927			if (HSYNC_POSITIVE)928				var->sync |= FB_SYNC_HOR_HIGH_ACT;929			if (VSYNC_POSITIVE)930				var->sync |= FB_SYNC_VERT_HIGH_ACT;931			return 0;932		}933	}934	return 1;935}936 937void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)938{939	unsigned char *block;940	int i, found = 0;941 942	if (edid == NULL)943		return;944 945	if (!(edid_checksum(edid)))946		return;947 948	if (!(edid_check_header(edid)))949		return;950 951	memset(specs, 0, sizeof(struct fb_monspecs));952 953	specs->version = edid[EDID_STRUCT_VERSION];954	specs->revision = edid[EDID_STRUCT_REVISION];955 956	DPRINTK("========================================\n");957	DPRINTK("Display Information (EDID)\n");958	DPRINTK("========================================\n");959	DPRINTK("   EDID Version %d.%d\n", (int) specs->version,960	       (int) specs->revision);961 962	parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);963 964	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;965	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {966		if (edid_is_serial_block(block)) {967			copy_string(block, specs->serial_no);968			DPRINTK("   Serial Number: %s\n", specs->serial_no);969		} else if (edid_is_ascii_block(block)) {970			copy_string(block, specs->ascii);971			DPRINTK("   ASCII Block: %s\n", specs->ascii);972		} else if (edid_is_monitor_block(block)) {973			copy_string(block, specs->monitor);974			DPRINTK("   Monitor Name: %s\n", specs->monitor);975		}976	}977 978	DPRINTK("   Display Characteristics:\n");979	get_monspecs(edid, specs);980 981	specs->modedb = fb_create_modedb(edid, &specs->modedb_len, specs);982	if (!specs->modedb)983		return;984 985	/*986	 * Workaround for buggy EDIDs that sets that the first987	 * detailed timing is preferred but has not detailed988	 * timing specified989	 */990	for (i = 0; i < specs->modedb_len; i++) {991		if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {992			found = 1;993			break;994		}995	}996 997	if (!found)998		specs->misc &= ~FB_MISC_1ST_DETAIL;999 1000	DPRINTK("========================================\n");1001}1002 1003/*1004 * VESA Generalized Timing Formula (GTF)1005 */1006 1007#define FLYBACK                     5501008#define V_FRONTPORCH                11009#define H_OFFSET                    401010#define H_SCALEFACTOR               201011#define H_BLANKSCALE                1281012#define H_GRADIENT                  6001013#define C_VAL                       301014#define M_VAL                       3001015 1016struct __fb_timings {1017	u32 dclk;1018	u32 hfreq;1019	u32 vfreq;1020	u32 hactive;1021	u32 vactive;1022	u32 hblank;1023	u32 vblank;1024	u32 htotal;1025	u32 vtotal;1026};1027 1028/**1029 * fb_get_vblank - get vertical blank time1030 * @hfreq: horizontal freq1031 *1032 * DESCRIPTION:1033 * vblank = right_margin + vsync_len + left_margin1034 *1035 *    given: right_margin = 1 (V_FRONTPORCH)1036 *           vsync_len    = 31037 *           flyback      = 5501038 *1039 *                          flyback * hfreq1040 *           left_margin  = --------------- - vsync_len1041 *                           10000001042 */1043static u32 fb_get_vblank(u32 hfreq)1044{1045	u32 vblank;1046 1047	vblank = (hfreq * FLYBACK)/1000;1048	vblank = (vblank + 500)/1000;1049	return (vblank + V_FRONTPORCH);1050}1051 1052/**1053 * fb_get_hblank_by_hfreq - get horizontal blank time given hfreq1054 * @hfreq: horizontal freq1055 * @xres: horizontal resolution in pixels1056 *1057 * DESCRIPTION:1058 *1059 *           xres * duty_cycle1060 * hblank = ------------------1061 *           100 - duty_cycle1062 *1063 * duty cycle = percent of htotal assigned to inactive display1064 * duty cycle = C - (M/Hfreq)1065 *1066 * where: C = ((offset - scale factor) * blank_scale)1067 *            -------------------------------------- + scale factor1068 *                        2561069 *        M = blank_scale * gradient1070 *1071 */1072static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)1073{1074	u32 c_val, m_val, duty_cycle, hblank;1075 1076	c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 +1077		 H_SCALEFACTOR) * 1000;1078	m_val = (H_BLANKSCALE * H_GRADIENT)/256;1079	m_val = (m_val * 1000000)/hfreq;1080	duty_cycle = c_val - m_val;1081	hblank = (xres * duty_cycle)/(100000 - duty_cycle);1082	return (hblank);1083}1084 1085/**1086 * fb_get_hblank_by_dclk - get horizontal blank time given pixelclock1087 * @dclk: pixelclock in Hz1088 * @xres: horizontal resolution in pixels1089 *1090 * DESCRIPTION:1091 *1092 *           xres * duty_cycle1093 * hblank = ------------------1094 *           100 - duty_cycle1095 *1096 * duty cycle = percent of htotal assigned to inactive display1097 * duty cycle = C - (M * h_period)1098 *1099 * where: h_period = SQRT(100 - C + (0.4 * xres * M)/dclk) + C - 1001100 *                   -----------------------------------------------1101 *                                    2 * M1102 *        M = 300;1103 *        C = 30;1104 */1105static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)1106{1107	u32 duty_cycle, h_period, hblank;1108 1109	dclk /= 1000;1110	h_period = 100 - C_VAL;1111	h_period *= h_period;1112	h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);1113	h_period *= 10000;1114 1115	h_period = int_sqrt(h_period);1116	h_period -= (100 - C_VAL) * 100;1117	h_period *= 1000;1118	h_period /= 2 * M_VAL;1119 1120	duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;1121	hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;1122	hblank &= ~15;1123	return (hblank);1124}1125 1126/**1127 * fb_get_hfreq - estimate hsync1128 * @vfreq: vertical refresh rate1129 * @yres: vertical resolution1130 *1131 * DESCRIPTION:1132 *1133 *          (yres + front_port) * vfreq * 10000001134 * hfreq = -------------------------------------1135 *          (1000000 - (vfreq * FLYBACK)1136 *1137 */1138 1139static u32 fb_get_hfreq(u32 vfreq, u32 yres)1140{1141	u32 divisor, hfreq;1142 1143	divisor = (1000000 - (vfreq * FLYBACK))/1000;1144	hfreq = (yres + V_FRONTPORCH) * vfreq  * 1000;1145	return (hfreq/divisor);1146}1147 1148static void fb_timings_vfreq(struct __fb_timings *timings)1149{1150	timings->hfreq = fb_get_hfreq(timings->vfreq, timings->vactive);1151	timings->vblank = fb_get_vblank(timings->hfreq);1152	timings->vtotal = timings->vactive + timings->vblank;1153	timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,1154						 timings->hactive);1155	timings->htotal = timings->hactive + timings->hblank;1156	timings->dclk = timings->htotal * timings->hfreq;1157}1158 1159static void fb_timings_hfreq(struct __fb_timings *timings)1160{1161	timings->vblank = fb_get_vblank(timings->hfreq);1162	timings->vtotal = timings->vactive + timings->vblank;1163	timings->vfreq = timings->hfreq/timings->vtotal;1164	timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,1165						 timings->hactive);1166	timings->htotal = timings->hactive + timings->hblank;1167	timings->dclk = timings->htotal * timings->hfreq;1168}1169 1170static void fb_timings_dclk(struct __fb_timings *timings)1171{1172	timings->hblank = fb_get_hblank_by_dclk(timings->dclk,1173						timings->hactive);1174	timings->htotal = timings->hactive + timings->hblank;1175	timings->hfreq = timings->dclk/timings->htotal;1176	timings->vblank = fb_get_vblank(timings->hfreq);1177	timings->vtotal = timings->vactive + timings->vblank;1178	timings->vfreq = timings->hfreq/timings->vtotal;1179}1180 1181/*1182 * fb_get_mode - calculates video mode using VESA GTF1183 * @flags: if: 0 - maximize vertical refresh rate1184 *             1 - vrefresh-driven calculation;1185 *             2 - hscan-driven calculation;1186 *             3 - pixelclock-driven calculation;1187 * @val: depending on @flags, ignored, vrefresh, hsync or pixelclock1188 * @var: pointer to fb_var_screeninfo1189 * @info: pointer to fb_info1190 *1191 * DESCRIPTION:1192 * Calculates video mode based on monitor specs using VESA GTF.1193 * The GTF is best for VESA GTF compliant monitors but is1194 * specifically formulated to work for older monitors as well.1195 *1196 * If @flag==0, the function will attempt to maximize the1197 * refresh rate.  Otherwise, it will calculate timings based on1198 * the flag and accompanying value.1199 *1200 * If FB_IGNOREMON bit is set in @flags, monitor specs will be1201 * ignored and @var will be filled with the calculated timings.1202 *1203 * All calculations are based on the VESA GTF Spreadsheet1204 * available at VESA's public ftp (https://www.vesa.org).1205 *1206 * NOTES:1207 * The timings generated by the GTF will be different from VESA1208 * DMT.  It might be a good idea to keep a table of standard1209 * VESA modes as well.  The GTF may also not work for some displays,1210 * such as, and especially, analog TV.1211 *1212 * REQUIRES:1213 * A valid info->monspecs, otherwise 'safe numbers' will be used.1214 */1215int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)1216{1217	struct __fb_timings *timings;1218	u32 interlace = 1, dscan = 1;1219	u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;1220 1221 1222	timings = kzalloc(sizeof(struct __fb_timings), GFP_KERNEL);1223 1224	if (!timings)1225		return -ENOMEM;1226 1227	/*1228	 * If monspecs are invalid, use values that are enough1229	 * for 640x480@601230	 */1231	if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||1232	    !info->monspecs.dclkmax ||1233	    info->monspecs.hfmax < info->monspecs.hfmin ||1234	    info->monspecs.vfmax < info->monspecs.vfmin ||1235	    info->monspecs.dclkmax < info->monspecs.dclkmin) {1236		hfmin = 29000; hfmax = 30000;1237		vfmin = 60; vfmax = 60;1238		dclkmin = 0; dclkmax = 25000000;1239	} else {1240		hfmin = info->monspecs.hfmin;1241		hfmax = info->monspecs.hfmax;1242		vfmin = info->monspecs.vfmin;1243		vfmax = info->monspecs.vfmax;1244		dclkmin = info->monspecs.dclkmin;1245		dclkmax = info->monspecs.dclkmax;1246	}1247 1248	timings->hactive = var->xres;1249	timings->vactive = var->yres;1250	if (var->vmode & FB_VMODE_INTERLACED) {1251		timings->vactive /= 2;1252		interlace = 2;1253	}1254	if (var->vmode & FB_VMODE_DOUBLE) {1255		timings->vactive *= 2;1256		dscan = 2;1257	}1258 1259	switch (flags & ~FB_IGNOREMON) {1260	case FB_MAXTIMINGS: /* maximize refresh rate */1261		timings->hfreq = hfmax;1262		fb_timings_hfreq(timings);1263		if (timings->vfreq > vfmax) {1264			timings->vfreq = vfmax;1265			fb_timings_vfreq(timings);1266		}1267		if (timings->dclk > dclkmax) {1268			timings->dclk = dclkmax;1269			fb_timings_dclk(timings);1270		}1271		break;1272	case FB_VSYNCTIMINGS: /* vrefresh driven */1273		timings->vfreq = val;1274		fb_timings_vfreq(timings);1275		break;1276	case FB_HSYNCTIMINGS: /* hsync driven */1277		timings->hfreq = val;1278		fb_timings_hfreq(timings);1279		break;1280	case FB_DCLKTIMINGS: /* pixelclock driven */1281		timings->dclk = PICOS2KHZ(val) * 1000;1282		fb_timings_dclk(timings);1283		break;1284	default:1285		err = -EINVAL;1286 1287	}1288 1289	if (err || (!(flags & FB_IGNOREMON) &&1290	    (timings->vfreq < vfmin || timings->vfreq > vfmax ||1291	     timings->hfreq < hfmin || timings->hfreq > hfmax ||1292	     timings->dclk < dclkmin || timings->dclk > dclkmax))) {1293		err = -EINVAL;1294	} else {1295		var->pixclock = KHZ2PICOS(timings->dclk/1000);1296		var->hsync_len = (timings->htotal * 8)/100;1297		var->right_margin = (timings->hblank/2) - var->hsync_len;1298		var->left_margin = timings->hblank - var->right_margin -1299			var->hsync_len;1300		var->vsync_len = (3 * interlace)/dscan;1301		var->lower_margin = (1 * interlace)/dscan;1302		var->upper_margin = (timings->vblank * interlace)/dscan -1303			(var->vsync_len + var->lower_margin);1304	}1305 1306	kfree(timings);1307	return err;1308}1309 1310#ifdef CONFIG_VIDEOMODE_HELPERS1311int fb_videomode_from_videomode(const struct videomode *vm,1312				struct fb_videomode *fbmode)1313{1314	unsigned int htotal, vtotal, total;1315 1316	fbmode->xres = vm->hactive;1317	fbmode->left_margin = vm->hback_porch;1318	fbmode->right_margin = vm->hfront_porch;1319	fbmode->hsync_len = vm->hsync_len;1320 1321	fbmode->yres = vm->vactive;1322	fbmode->upper_margin = vm->vback_porch;1323	fbmode->lower_margin = vm->vfront_porch;1324	fbmode->vsync_len = vm->vsync_len;1325 1326	/* prevent division by zero in KHZ2PICOS macro */1327	fbmode->pixclock = vm->pixelclock ?1328			KHZ2PICOS(vm->pixelclock / 1000) : 0;1329 1330	fbmode->sync = 0;1331	fbmode->vmode = 0;1332	if (vm->flags & DISPLAY_FLAGS_HSYNC_HIGH)1333		fbmode->sync |= FB_SYNC_HOR_HIGH_ACT;1334	if (vm->flags & DISPLAY_FLAGS_VSYNC_HIGH)1335		fbmode->sync |= FB_SYNC_VERT_HIGH_ACT;1336	if (vm->flags & DISPLAY_FLAGS_INTERLACED)1337		fbmode->vmode |= FB_VMODE_INTERLACED;1338	if (vm->flags & DISPLAY_FLAGS_DOUBLESCAN)1339		fbmode->vmode |= FB_VMODE_DOUBLE;1340	fbmode->flag = 0;1341 1342	htotal = vm->hactive + vm->hfront_porch + vm->hback_porch +1343		 vm->hsync_len;1344	vtotal = vm->vactive + vm->vfront_porch + vm->vback_porch +1345		 vm->vsync_len;1346	/* prevent division by zero */1347	total = htotal * vtotal;1348	if (total) {1349		fbmode->refresh = vm->pixelclock / total;1350	/* a mode must have htotal and vtotal != 0 or it is invalid */1351	} else {1352		fbmode->refresh = 0;1353		return -EINVAL;1354	}1355 1356	return 0;1357}1358EXPORT_SYMBOL_GPL(fb_videomode_from_videomode);1359 1360#ifdef CONFIG_OF1361static inline void dump_fb_videomode(const struct fb_videomode *m)1362{1363	pr_debug("fb_videomode = %ux%u@%uHz (%ukHz) %u %u %u %u %u %u %u %u %u\n",1364		 m->xres, m->yres, m->refresh, m->pixclock, m->left_margin,1365		 m->right_margin, m->upper_margin, m->lower_margin,1366		 m->hsync_len, m->vsync_len, m->sync, m->vmode, m->flag);1367}1368 1369/**1370 * of_get_fb_videomode - get a fb_videomode from devicetree1371 * @np: device_node with the timing specification1372 * @fb: will be set to the return value1373 * @index: index into the list of display timings in devicetree1374 *1375 * DESCRIPTION:1376 * This function is expensive and should only be used, if only one mode is to be1377 * read from DT. To get multiple modes start with of_get_display_timings ond1378 * work with that instead.1379 */1380int of_get_fb_videomode(struct device_node *np, struct fb_videomode *fb,1381			int index)1382{1383	struct videomode vm;1384	int ret;1385 1386	ret = of_get_videomode(np, &vm, index);1387	if (ret)1388		return ret;1389 1390	ret = fb_videomode_from_videomode(&vm, fb);1391	if (ret)1392		return ret;1393 1394	pr_debug("%pOF: got %dx%d display mode\n",1395		np, vm.hactive, vm.vactive);1396	dump_fb_videomode(fb);1397 1398	return 0;1399}1400EXPORT_SYMBOL_GPL(of_get_fb_videomode);1401#endif /* CONFIG_OF */1402#endif /* CONFIG_VIDEOMODE_HELPERS */1403 1404#else1405int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)1406{1407	return 1;1408}1409void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)1410{1411}1412void fb_destroy_modedb(struct fb_videomode *modedb)1413{1414}1415int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,1416		struct fb_info *info)1417{1418	return -EINVAL;1419}1420#endif /* CONFIG_FB_MODE_HELPERS */1421 1422/*1423 * fb_validate_mode - validates var against monitor capabilities1424 * @var: pointer to fb_var_screeninfo1425 * @info: pointer to fb_info1426 *1427 * DESCRIPTION:1428 * Validates video mode against monitor capabilities specified in1429 * info->monspecs.1430 *1431 * REQUIRES:1432 * A valid info->monspecs.1433 */1434int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)1435{1436	u32 hfreq, vfreq, htotal, vtotal, pixclock;1437	u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;1438 1439	/*1440	 * If monspecs are invalid, use values that are enough1441	 * for 640x480@601442	 */1443	if (!info->monspecs.hfmax || !info->monspecs.vfmax ||1444	    !info->monspecs.dclkmax ||1445	    info->monspecs.hfmax < info->monspecs.hfmin ||1446	    info->monspecs.vfmax < info->monspecs.vfmin ||1447	    info->monspecs.dclkmax < info->monspecs.dclkmin) {1448		hfmin = 29000; hfmax = 30000;1449		vfmin = 60; vfmax = 60;1450		dclkmin = 0; dclkmax = 25000000;1451	} else {1452		hfmin = info->monspecs.hfmin;1453		hfmax = info->monspecs.hfmax;1454		vfmin = info->monspecs.vfmin;1455		vfmax = info->monspecs.vfmax;1456		dclkmin = info->monspecs.dclkmin;1457		dclkmax = info->monspecs.dclkmax;1458	}1459 1460	if (!var->pixclock)1461		return -EINVAL;1462	pixclock = PICOS2KHZ(var->pixclock) * 1000;1463 1464	htotal = var->xres + var->right_margin + var->hsync_len +1465		var->left_margin;1466	vtotal = var->yres + var->lower_margin + var->vsync_len +1467		var->upper_margin;1468 1469	if (var->vmode & FB_VMODE_INTERLACED)1470		vtotal /= 2;1471	if (var->vmode & FB_VMODE_DOUBLE)1472		vtotal *= 2;1473 1474	hfreq = pixclock/htotal;1475	hfreq = (hfreq + 500) / 1000 * 1000;1476 1477	vfreq = hfreq/vtotal;1478 1479	return (vfreq < vfmin || vfreq > vfmax ||1480		hfreq < hfmin || hfreq > hfmax ||1481		pixclock < dclkmin || pixclock > dclkmax) ?1482		-EINVAL : 0;1483}1484 1485#if defined(CONFIG_FIRMWARE_EDID) && defined(CONFIG_X86)1486 1487/*1488 * We need to ensure that the EDID block is only returned for1489 * the primary graphics adapter.1490 */1491 1492const unsigned char *fb_firmware_edid(struct device *device)1493{1494	struct pci_dev *dev = NULL;1495	struct resource *res = NULL;1496	unsigned char *edid = NULL;1497 1498	if (device)1499		dev = to_pci_dev(device);1500 1501	if (dev)1502		res = &dev->resource[PCI_ROM_RESOURCE];1503 1504	if (res && res->flags & IORESOURCE_ROM_SHADOW)1505		edid = edid_info.dummy;1506 1507	return edid;1508}1509#else1510const unsigned char *fb_firmware_edid(struct device *device)1511{1512	return NULL;1513}1514#endif1515EXPORT_SYMBOL(fb_firmware_edid);1516 1517EXPORT_SYMBOL(fb_parse_edid);1518EXPORT_SYMBOL(fb_edid_to_monspecs);1519EXPORT_SYMBOL(fb_get_mode);1520EXPORT_SYMBOL(fb_validate_mode);1521EXPORT_SYMBOL(fb_destroy_modedb);1522