2 * linux/drivers/video/fbmon.c
4 * Copyright (C) 2002 James Simmons <jsimmons@users.sf.net>
8 * The EDID Parser is a conglomeration from the following sources:
10 * 1. SciTech SNAP Graphics Architecture
11 * Copyright (C) 1991-2002 SciTech Software, Inc. All rights reserved.
13 * 2. XFree86 4.3.0, interpret_edid.c
14 * Copyright 1998 by Egbert Eich <Egbert.Eich@Physik.TU-Darmstadt.DE>
16 * 3. John Fremlin <vii@users.sourceforge.net> and
17 * Ani Joshi <ajoshi@unixbox.com>
19 * Generalized Timing Formula is derived from:
21 * GTF Spreadsheet by Andy Morrish (1/5/97)
22 * available at http://www.vesa.org
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
30 #include <linux/module.h>
31 #include <linux/pci.h>
32 #include <linux/slab.h>
33 #include <video/edid.h>
36 #include <asm/pci-bridge.h>
44 #undef DEBUG /* define this for verbose EDID parsing output */
47 #define DPRINTK(fmt, args...) printk(fmt,## args)
49 #define DPRINTK(fmt, args...)
52 #define FBMON_FIX_HEADER 1
53 #define FBMON_FIX_INPUT 2
54 #define FBMON_FIX_TIMINGS 3
56 #ifdef CONFIG_FB_MODE_HELPERS
63 static const struct broken_edid brokendb[] = {
66 .manufacturer = "DEC",
68 .fix = FBMON_FIX_HEADER,
70 /* ViewSonic PF775a */
72 .manufacturer = "VSC",
74 .fix = FBMON_FIX_INPUT,
78 .manufacturer = "SHP",
80 .fix = FBMON_FIX_TIMINGS,
84 static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
85 0xff, 0xff, 0xff, 0x00
88 static void copy_string(unsigned char *c, unsigned char *s)
92 for (i = 0; (i < 13 && *c != 0x0A); i++)
95 while (i-- && (*--s == 0x20)) *s = 0;
98 static int edid_is_serial_block(unsigned char *block)
100 if ((block[0] == 0x00) && (block[1] == 0x00) &&
101 (block[2] == 0x00) && (block[3] == 0xff) &&
108 static int edid_is_ascii_block(unsigned char *block)
110 if ((block[0] == 0x00) && (block[1] == 0x00) &&
111 (block[2] == 0x00) && (block[3] == 0xfe) &&
118 static int edid_is_limits_block(unsigned char *block)
120 if ((block[0] == 0x00) && (block[1] == 0x00) &&
121 (block[2] == 0x00) && (block[3] == 0xfd) &&
128 static int edid_is_monitor_block(unsigned char *block)
130 if ((block[0] == 0x00) && (block[1] == 0x00) &&
131 (block[2] == 0x00) && (block[3] == 0xfc) &&
138 static int edid_is_timing_block(unsigned char *block)
140 if ((block[0] != 0x00) || (block[1] != 0x00) ||
141 (block[2] != 0x00) || (block[4] != 0x00))
147 static int check_edid(unsigned char *edid)
149 unsigned char *block = edid + ID_MANUFACTURER_NAME, manufacturer[4];
152 int i, fix = 0, ret = 0;
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) + '@';
159 model = block[2] + (block[3] << 8);
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;
170 case FBMON_FIX_HEADER:
171 for (i = 0; i < 8; i++) {
172 if (edid[i] != edid_v1_header[i]) {
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)
185 case FBMON_FIX_TIMINGS:
186 b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
189 for (i = 0; i < 4; i++) {
190 if (edid_is_limits_block(b)) {
195 b += DETAILED_TIMING_DESCRIPTION_SIZE;
202 printk("fbmon: The EDID Block of "
203 "Manufacturer: %s Model: 0x%x is known to "
204 "be broken,\n", manufacturer, model);
209 static void fix_edid(unsigned char *edid, int fix)
212 unsigned char *b, csum = 0;
215 case FBMON_FIX_HEADER:
216 printk("fbmon: trying a header reconstruct\n");
217 memcpy(edid, edid_v1_header, 8);
219 case FBMON_FIX_INPUT:
220 printk("fbmon: trying to fix input type\n");
221 b = edid + EDID_STRUCT_DISPLAY;
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))) {
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*/
247 b += DETAILED_TIMING_DESCRIPTION_SIZE;
250 for (i = 0; i < EDID_LENGTH - 1; i++)
253 edid[127] = 256 - csum;
258 static int edid_checksum(unsigned char *edid)
260 unsigned char csum = 0, all_null = 0;
261 int i, err = 0, fix = check_edid(edid);
266 for (i = 0; i < EDID_LENGTH; i++) {
271 if (csum == 0x00 && all_null) {
272 /* checksum passed, everything's good */
279 static int edid_check_header(unsigned char *edid)
281 int i, err = 1, fix = check_edid(edid);
286 for (i = 0; i < 8; i++) {
287 if (edid[i] != edid_v1_header[i])
294 static void parse_vendor_block(unsigned char *block, struct fb_monspecs *specs)
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);
312 static void get_dpms_capabilities(unsigned char flags,
313 struct fb_monspecs *specs)
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");
328 static void get_chroma(unsigned char *block, struct fb_monspecs *specs)
332 DPRINTK(" Chroma\n");
333 /* Chromaticity data */
334 tmp = ((block[5] & (3 << 6)) >> 6) | (block[0x7] << 2);
337 specs->chroma.redx = tmp/1024;
338 DPRINTK(" RedX: 0.%03d ", specs->chroma.redx);
340 tmp = ((block[5] & (3 << 4)) >> 4) | (block[0x8] << 2);
343 specs->chroma.redy = tmp/1024;
344 DPRINTK("RedY: 0.%03d\n", specs->chroma.redy);
346 tmp = ((block[5] & (3 << 2)) >> 2) | (block[0x9] << 2);
349 specs->chroma.greenx = tmp/1024;
350 DPRINTK(" GreenX: 0.%03d ", specs->chroma.greenx);
352 tmp = (block[5] & 3) | (block[0xa] << 2);
355 specs->chroma.greeny = tmp/1024;
356 DPRINTK("GreenY: 0.%03d\n", specs->chroma.greeny);
358 tmp = ((block[6] & (3 << 6)) >> 6) | (block[0xb] << 2);
361 specs->chroma.bluex = tmp/1024;
362 DPRINTK(" BlueX: 0.%03d ", specs->chroma.bluex);
364 tmp = ((block[6] & (3 << 4)) >> 4) | (block[0xc] << 2);
367 specs->chroma.bluey = tmp/1024;
368 DPRINTK("BlueY: 0.%03d\n", specs->chroma.bluey);
370 tmp = ((block[6] & (3 << 2)) >> 2) | (block[0xd] << 2);
373 specs->chroma.whitex = tmp/1024;
374 DPRINTK(" WhiteX: 0.%03d ", specs->chroma.whitex);
376 tmp = (block[6] & 3) | (block[0xe] << 2);
379 specs->chroma.whitey = tmp/1024;
380 DPRINTK("WhiteY: 0.%03d\n", specs->chroma.whitey);
383 static void calc_mode_timings(int xres, int yres, int refresh,
384 struct fb_videomode *mode)
386 struct fb_var_screeninfo *var;
388 var = kzalloc(sizeof(struct fb_var_screeninfo), GFP_KERNEL);
393 fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON,
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;
411 static int get_est_timing(unsigned char *block, struct fb_videomode *mode)
418 calc_mode_timings(720, 400, 70, &mode[num]);
419 mode[num++].flag = FB_MODE_IS_CALCULATED;
420 DPRINTK(" 720x400@70Hz\n");
423 calc_mode_timings(720, 400, 88, &mode[num]);
424 mode[num++].flag = FB_MODE_IS_CALCULATED;
425 DPRINTK(" 720x400@88Hz\n");
428 mode[num++] = vesa_modes[3];
429 DPRINTK(" 640x480@60Hz\n");
432 calc_mode_timings(640, 480, 67, &mode[num]);
433 mode[num++].flag = FB_MODE_IS_CALCULATED;
434 DPRINTK(" 640x480@67Hz\n");
437 mode[num++] = vesa_modes[4];
438 DPRINTK(" 640x480@72Hz\n");
441 mode[num++] = vesa_modes[5];
442 DPRINTK(" 640x480@75Hz\n");
445 mode[num++] = vesa_modes[7];
446 DPRINTK(" 800x600@56Hz\n");
449 mode[num++] = vesa_modes[8];
450 DPRINTK(" 800x600@60Hz\n");
455 mode[num++] = vesa_modes[9];
456 DPRINTK(" 800x600@72Hz\n");
459 mode[num++] = vesa_modes[10];
460 DPRINTK(" 800x600@75Hz\n");
463 calc_mode_timings(832, 624, 75, &mode[num]);
464 mode[num++].flag = FB_MODE_IS_CALCULATED;
465 DPRINTK(" 832x624@75Hz\n");
468 mode[num++] = vesa_modes[12];
469 DPRINTK(" 1024x768@87Hz Interlaced\n");
472 mode[num++] = vesa_modes[13];
473 DPRINTK(" 1024x768@60Hz\n");
476 mode[num++] = vesa_modes[14];
477 DPRINTK(" 1024x768@70Hz\n");
480 mode[num++] = vesa_modes[15];
481 DPRINTK(" 1024x768@75Hz\n");
484 mode[num++] = vesa_modes[21];
485 DPRINTK(" 1280x1024@75Hz\n");
489 mode[num++] = vesa_modes[17];
490 DPRINTK(" 1152x870@75Hz\n");
492 DPRINTK(" Manufacturer's mask: %x\n",c&0x7F);
496 static int get_std_timing(unsigned char *block, struct fb_videomode *mode)
498 int xres, yres = 0, refresh, ratio, i;
500 xres = (block[0] + 31) * 8;
504 ratio = (block[1] & 0xc0) >> 6;
516 yres = (xres * 9)/16;
519 refresh = (block[1] & 0x3f) + 60;
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;
531 calc_mode_timings(xres, yres, refresh, mode);
535 static int get_dst_timing(unsigned char *block,
536 struct fb_videomode *mode)
540 for (j = 0; j < 6; j++, block += STD_TIMING_DESCRIPTION_SIZE)
541 num += get_std_timing(block, &mode[num]);
546 static void get_detailed_timing(unsigned char *block,
547 struct fb_videomode *mode)
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 -
559 mode->lower_margin = V_SYNC_OFFSET;
560 mode->hsync_len = H_SYNC_WIDTH;
561 mode->vsync_len = V_SYNC_WIDTH;
563 mode->sync |= FB_SYNC_HOR_HIGH_ACT;
565 mode->sync |= FB_SYNC_VERT_HIGH_ACT;
566 mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *
567 (V_ACTIVE + V_BLANKING));
570 mode->upper_margin *= 2;
571 mode->lower_margin *= 2;
572 mode->vsync_len *= 2;
573 mode->vmode |= FB_VMODE_INTERLACED;
575 mode->flag = FB_MODE_IS_DETAILED;
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) ? "+" : "-");
587 * fb_create_modedb - create video mode database
589 * @dbsize: database size
591 * RETURNS: struct fb_videomode, @dbsize contains length of database
594 * This function builds a mode database using the contents of the EDID
597 static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize)
599 struct fb_videomode *mode, *m;
600 unsigned char *block;
601 int num = 0, i, first = 1;
603 mode = kzalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
607 if (edid == NULL || !edid_checksum(edid) ||
608 !edid_check_header(edid)) {
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]);
621 mode[num].flag |= FB_MODE_IS_FIRST;
628 DPRINTK(" Supported VESA Modes\n");
629 block = edid + ESTABLISHED_TIMING_1;
630 num += get_est_timing(block, &mode[num]);
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]);
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]);
643 /* Yikes, EDID data is totally useless */
650 m = kmalloc(num * sizeof(struct fb_videomode), GFP_KERNEL);
653 memmove(m, mode, num * sizeof(struct fb_videomode));
659 * fb_destroy_modedb - destroys mode database
660 * @modedb: mode database to destroy
663 * Destroy mode database created by fb_create_modedb
665 void fb_destroy_modedb(struct fb_videomode *modedb)
670 static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
673 unsigned char *block;
675 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
677 DPRINTK(" Monitor Operating Limits: ");
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;
688 DPRINTK("From EDID\n");
693 /* estimate monitor limits based on modes supported */
695 struct fb_videomode *modes, *mode;
696 int num_modes, hz, hscan, pixclock;
699 modes = fb_create_modedb(edid, &num_modes);
701 DPRINTK("None Available\n");
706 for (i = 0; i < num_modes; i++) {
708 pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
709 htotal = mode->xres + mode->right_margin + mode->hsync_len
711 vtotal = mode->yres + mode->lower_margin + mode->vsync_len
712 + mode->upper_margin;
714 if (mode->vmode & FB_VMODE_INTERLACED)
717 if (mode->vmode & FB_VMODE_DOUBLE)
720 hscan = (pixclock + htotal / 2) / htotal;
721 hscan = (hscan + 500) / 1000 * 1000;
722 hz = (hscan + vtotal / 2) / vtotal;
724 if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
725 specs->dclkmax = pixclock;
727 if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
728 specs->dclkmin = pixclock;
730 if (specs->hfmax == 0 || specs->hfmax < hscan)
731 specs->hfmax = hscan;
733 if (specs->hfmin == 0 || specs->hfmin > hscan)
734 specs->hfmin = hscan;
736 if (specs->vfmax == 0 || specs->vfmax < hz)
739 if (specs->vfmin == 0 || specs->vfmin > hz)
742 DPRINTK("Extrapolated\n");
743 fb_destroy_modedb(modes);
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);
751 static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
753 unsigned char c, *block;
755 block = edid + EDID_STRUCT_DISPLAY;
757 fb_get_monitor_limits(edid, specs);
762 specs->input |= FB_DISP_DDI;
763 DPRINTK(" Digital Display Input");
765 DPRINTK(" Analog Display Input: Input Voltage - ");
766 switch ((block[0] & 0x60) >> 5) {
768 DPRINTK("0.700V/0.300V");
769 specs->input |= FB_DISP_ANA_700_300;
772 DPRINTK("0.714V/0.286V");
773 specs->input |= FB_DISP_ANA_714_286;
776 DPRINTK("1.000V/0.400V");
777 specs->input |= FB_DISP_ANA_1000_400;
780 DPRINTK("0.700V/0.000V");
781 specs->input |= FB_DISP_ANA_700_000;
785 DPRINTK("\n Sync: ");
788 DPRINTK(" Configurable signal level\n");
792 DPRINTK("Blank to Blank ");
793 specs->signal |= FB_SIGNAL_BLANK_BLANK;
796 DPRINTK("Separate ");
797 specs->signal |= FB_SIGNAL_SEPARATE;
800 DPRINTK("Composite ");
801 specs->signal |= FB_SIGNAL_COMPOSITE;
804 DPRINTK("Sync on Green ");
805 specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
808 DPRINTK("Serration on ");
809 specs->signal |= FB_SIGNAL_SERRATION_ON;
812 specs->max_x = block[1];
813 specs->max_y = block[2];
814 DPRINTK(" Max H-size in cm: ");
816 DPRINTK("%d\n", specs->max_x);
818 DPRINTK("variable\n");
819 DPRINTK(" Max V-size in cm: ");
821 DPRINTK("%d\n", specs->max_y);
823 DPRINTK("variable\n");
826 specs->gamma = c+100;
828 DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
830 get_dpms_capabilities(block[4], specs);
832 switch ((block[4] & 0x18) >> 3) {
834 DPRINTK(" Monochrome/Grayscale\n");
835 specs->input |= FB_DISP_MONO;
838 DPRINTK(" RGB Color Display\n");
839 specs->input |= FB_DISP_RGB;
842 DPRINTK(" Non-RGB Multicolor Display\n");
843 specs->input |= FB_DISP_MULTI;
846 DPRINTK(" Unknown\n");
847 specs->input |= FB_DISP_UNKNOWN;
851 get_chroma(block, specs);
856 DPRINTK(" Default color format is primary\n");
857 specs->misc |= FB_MISC_PRIM_COLOR;
860 DPRINTK(" First DETAILED Timing is preferred\n");
861 specs->misc |= FB_MISC_1ST_DETAIL;
864 printk(" Display is GTF capable\n");
869 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
872 unsigned char *block;
874 if (edid == NULL || var == NULL)
877 if (!(edid_checksum(edid)))
880 if (!(edid_check_header(edid)))
883 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
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 -
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);
903 var->sync |= FB_SYNC_HOR_HIGH_ACT;
905 var->sync |= FB_SYNC_VERT_HIGH_ACT;
912 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
914 unsigned char *block;
920 if (!(edid_checksum(edid)))
923 if (!(edid_check_header(edid)))
926 memset(specs, 0, sizeof(struct fb_monspecs));
928 specs->version = edid[EDID_STRUCT_VERSION];
929 specs->revision = edid[EDID_STRUCT_REVISION];
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);
937 parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);
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);
953 DPRINTK(" Display Characteristics:\n");
954 get_monspecs(edid, specs);
956 specs->modedb = fb_create_modedb(edid, &specs->modedb_len);
959 * Workaround for buggy EDIDs that sets that the first
960 * detailed timing is preferred but has not detailed
963 for (i = 0; i < specs->modedb_len; i++) {
964 if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {
971 specs->misc &= ~FB_MISC_1ST_DETAIL;
973 DPRINTK("========================================\n");
977 * VESA Generalized Timing Formula (GTF)
981 #define V_FRONTPORCH 1
983 #define H_SCALEFACTOR 20
984 #define H_BLANKSCALE 128
985 #define H_GRADIENT 600
989 struct __fb_timings {
1002 * fb_get_vblank - get vertical blank time
1003 * @hfreq: horizontal freq
1006 * vblank = right_margin + vsync_len + left_margin
1008 * given: right_margin = 1 (V_FRONTPORCH)
1013 * left_margin = --------------- - vsync_len
1016 static u32 fb_get_vblank(u32 hfreq)
1020 vblank = (hfreq * FLYBACK)/1000;
1021 vblank = (vblank + 500)/1000;
1022 return (vblank + V_FRONTPORCH);
1026 * fb_get_hblank_by_freq - get horizontal blank time given hfreq
1027 * @hfreq: horizontal freq
1028 * @xres: horizontal resolution in pixels
1033 * hblank = ------------------
1036 * duty cycle = percent of htotal assigned to inactive display
1037 * duty cycle = C - (M/Hfreq)
1039 * where: C = ((offset - scale factor) * blank_scale)
1040 * -------------------------------------- + scale factor
1042 * M = blank_scale * gradient
1045 static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
1047 u32 c_val, m_val, duty_cycle, hblank;
1049 c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 +
1050 H_SCALEFACTOR) * 1000;
1051 m_val = (H_BLANKSCALE * H_GRADIENT)/256;
1052 m_val = (m_val * 1000000)/hfreq;
1053 duty_cycle = c_val - m_val;
1054 hblank = (xres * duty_cycle)/(100000 - duty_cycle);
1059 * fb_get_hblank_by_dclk - get horizontal blank time given pixelclock
1060 * @dclk: pixelclock in Hz
1061 * @xres: horizontal resolution in pixels
1066 * hblank = ------------------
1069 * duty cycle = percent of htotal assigned to inactive display
1070 * duty cycle = C - (M * h_period)
1072 * where: h_period = SQRT(100 - C + (0.4 * xres * M)/dclk) + C - 100
1073 * -----------------------------------------------
1079 static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)
1081 u32 duty_cycle, h_period, hblank;
1084 h_period = 100 - C_VAL;
1085 h_period *= h_period;
1086 h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);
1089 h_period = int_sqrt(h_period);
1090 h_period -= (100 - C_VAL) * 100;
1092 h_period /= 2 * M_VAL;
1094 duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;
1095 hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;
1101 * fb_get_hfreq - estimate hsync
1102 * @vfreq: vertical refresh rate
1103 * @yres: vertical resolution
1107 * (yres + front_port) * vfreq * 1000000
1108 * hfreq = -------------------------------------
1109 * (1000000 - (vfreq * FLYBACK)
1113 static u32 fb_get_hfreq(u32 vfreq, u32 yres)
1117 divisor = (1000000 - (vfreq * FLYBACK))/1000;
1118 hfreq = (yres + V_FRONTPORCH) * vfreq * 1000;
1119 return (hfreq/divisor);
1122 static void fb_timings_vfreq(struct __fb_timings *timings)
1124 timings->hfreq = fb_get_hfreq(timings->vfreq, timings->vactive);
1125 timings->vblank = fb_get_vblank(timings->hfreq);
1126 timings->vtotal = timings->vactive + timings->vblank;
1127 timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1129 timings->htotal = timings->hactive + timings->hblank;
1130 timings->dclk = timings->htotal * timings->hfreq;
1133 static void fb_timings_hfreq(struct __fb_timings *timings)
1135 timings->vblank = fb_get_vblank(timings->hfreq);
1136 timings->vtotal = timings->vactive + timings->vblank;
1137 timings->vfreq = timings->hfreq/timings->vtotal;
1138 timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1140 timings->htotal = timings->hactive + timings->hblank;
1141 timings->dclk = timings->htotal * timings->hfreq;
1144 static void fb_timings_dclk(struct __fb_timings *timings)
1146 timings->hblank = fb_get_hblank_by_dclk(timings->dclk,
1148 timings->htotal = timings->hactive + timings->hblank;
1149 timings->hfreq = timings->dclk/timings->htotal;
1150 timings->vblank = fb_get_vblank(timings->hfreq);
1151 timings->vtotal = timings->vactive + timings->vblank;
1152 timings->vfreq = timings->hfreq/timings->vtotal;
1156 * fb_get_mode - calculates video mode using VESA GTF
1157 * @flags: if: 0 - maximize vertical refresh rate
1158 * 1 - vrefresh-driven calculation;
1159 * 2 - hscan-driven calculation;
1160 * 3 - pixelclock-driven calculation;
1161 * @val: depending on @flags, ignored, vrefresh, hsync or pixelclock
1162 * @var: pointer to fb_var_screeninfo
1163 * @info: pointer to fb_info
1166 * Calculates video mode based on monitor specs using VESA GTF.
1167 * The GTF is best for VESA GTF compliant monitors but is
1168 * specifically formulated to work for older monitors as well.
1170 * If @flag==0, the function will attempt to maximize the
1171 * refresh rate. Otherwise, it will calculate timings based on
1172 * the flag and accompanying value.
1174 * If FB_IGNOREMON bit is set in @flags, monitor specs will be
1175 * ignored and @var will be filled with the calculated timings.
1177 * All calculations are based on the VESA GTF Spreadsheet
1178 * available at VESA's public ftp (http://www.vesa.org).
1181 * The timings generated by the GTF will be different from VESA
1182 * DMT. It might be a good idea to keep a table of standard
1183 * VESA modes as well. The GTF may also not work for some displays,
1184 * such as, and especially, analog TV.
1187 * A valid info->monspecs, otherwise 'safe numbers' will be used.
1189 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)
1191 struct __fb_timings *timings;
1192 u32 interlace = 1, dscan = 1;
1193 u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;
1196 timings = kzalloc(sizeof(struct __fb_timings), GFP_KERNEL);
1202 * If monspecs are invalid, use values that are enough
1205 if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||
1206 !info->monspecs.dclkmax ||
1207 info->monspecs.hfmax < info->monspecs.hfmin ||
1208 info->monspecs.vfmax < info->monspecs.vfmin ||
1209 info->monspecs.dclkmax < info->monspecs.dclkmin) {
1210 hfmin = 29000; hfmax = 30000;
1211 vfmin = 60; vfmax = 60;
1212 dclkmin = 0; dclkmax = 25000000;
1214 hfmin = info->monspecs.hfmin;
1215 hfmax = info->monspecs.hfmax;
1216 vfmin = info->monspecs.vfmin;
1217 vfmax = info->monspecs.vfmax;
1218 dclkmin = info->monspecs.dclkmin;
1219 dclkmax = info->monspecs.dclkmax;
1222 timings->hactive = var->xres;
1223 timings->vactive = var->yres;
1224 if (var->vmode & FB_VMODE_INTERLACED) {
1225 timings->vactive /= 2;
1228 if (var->vmode & FB_VMODE_DOUBLE) {
1229 timings->vactive *= 2;
1233 switch (flags & ~FB_IGNOREMON) {
1234 case FB_MAXTIMINGS: /* maximize refresh rate */
1235 timings->hfreq = hfmax;
1236 fb_timings_hfreq(timings);
1237 if (timings->vfreq > vfmax) {
1238 timings->vfreq = vfmax;
1239 fb_timings_vfreq(timings);
1241 if (timings->dclk > dclkmax) {
1242 timings->dclk = dclkmax;
1243 fb_timings_dclk(timings);
1246 case FB_VSYNCTIMINGS: /* vrefresh driven */
1247 timings->vfreq = val;
1248 fb_timings_vfreq(timings);
1250 case FB_HSYNCTIMINGS: /* hsync driven */
1251 timings->hfreq = val;
1252 fb_timings_hfreq(timings);
1254 case FB_DCLKTIMINGS: /* pixelclock driven */
1255 timings->dclk = PICOS2KHZ(val) * 1000;
1256 fb_timings_dclk(timings);
1263 if (err || (!(flags & FB_IGNOREMON) &&
1264 (timings->vfreq < vfmin || timings->vfreq > vfmax ||
1265 timings->hfreq < hfmin || timings->hfreq > hfmax ||
1266 timings->dclk < dclkmin || timings->dclk > dclkmax))) {
1269 var->pixclock = KHZ2PICOS(timings->dclk/1000);
1270 var->hsync_len = (timings->htotal * 8)/100;
1271 var->right_margin = (timings->hblank/2) - var->hsync_len;
1272 var->left_margin = timings->hblank - var->right_margin -
1274 var->vsync_len = (3 * interlace)/dscan;
1275 var->lower_margin = (1 * interlace)/dscan;
1276 var->upper_margin = (timings->vblank * interlace)/dscan -
1277 (var->vsync_len + var->lower_margin);
1284 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
1288 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1292 void fb_destroy_modedb(struct fb_videomode *modedb)
1295 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
1296 struct fb_info *info)
1300 #endif /* CONFIG_FB_MODE_HELPERS */
1303 * fb_validate_mode - validates var against monitor capabilities
1304 * @var: pointer to fb_var_screeninfo
1305 * @info: pointer to fb_info
1308 * Validates video mode against monitor capabilities specified in
1312 * A valid info->monspecs.
1314 int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
1316 u32 hfreq, vfreq, htotal, vtotal, pixclock;
1317 u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
1320 * If monspecs are invalid, use values that are enough
1323 if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
1324 !info->monspecs.dclkmax ||
1325 info->monspecs.hfmax < info->monspecs.hfmin ||
1326 info->monspecs.vfmax < info->monspecs.vfmin ||
1327 info->monspecs.dclkmax < info->monspecs.dclkmin) {
1328 hfmin = 29000; hfmax = 30000;
1329 vfmin = 60; vfmax = 60;
1330 dclkmin = 0; dclkmax = 25000000;
1332 hfmin = info->monspecs.hfmin;
1333 hfmax = info->monspecs.hfmax;
1334 vfmin = info->monspecs.vfmin;
1335 vfmax = info->monspecs.vfmax;
1336 dclkmin = info->monspecs.dclkmin;
1337 dclkmax = info->monspecs.dclkmax;
1342 pixclock = PICOS2KHZ(var->pixclock) * 1000;
1344 htotal = var->xres + var->right_margin + var->hsync_len +
1346 vtotal = var->yres + var->lower_margin + var->vsync_len +
1349 if (var->vmode & FB_VMODE_INTERLACED)
1351 if (var->vmode & FB_VMODE_DOUBLE)
1354 hfreq = pixclock/htotal;
1355 hfreq = (hfreq + 500) / 1000 * 1000;
1357 vfreq = hfreq/vtotal;
1359 return (vfreq < vfmin || vfreq > vfmax ||
1360 hfreq < hfmin || hfreq > hfmax ||
1361 pixclock < dclkmin || pixclock > dclkmax) ?
1365 #if defined(CONFIG_FIRMWARE_EDID) && defined(CONFIG_X86)
1368 * We need to ensure that the EDID block is only returned for
1369 * the primary graphics adapter.
1372 const unsigned char *fb_firmware_edid(struct device *device)
1374 struct pci_dev *dev = NULL;
1375 struct resource *res = NULL;
1376 unsigned char *edid = NULL;
1379 dev = to_pci_dev(device);
1382 res = &dev->resource[PCI_ROM_RESOURCE];
1384 if (res && res->flags & IORESOURCE_ROM_SHADOW)
1385 edid = edid_info.dummy;
1390 const unsigned char *fb_firmware_edid(struct device *device)
1395 EXPORT_SYMBOL(fb_firmware_edid);
1397 EXPORT_SYMBOL(fb_parse_edid);
1398 EXPORT_SYMBOL(fb_edid_to_monspecs);
1399 EXPORT_SYMBOL(fb_get_mode);
1400 EXPORT_SYMBOL(fb_validate_mode);
1401 EXPORT_SYMBOL(fb_destroy_modedb);