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 <video/edid.h>
35 #include <asm/pci-bridge.h>
43 #undef DEBUG /* define this for verbose EDID parsing output */
46 #define DPRINTK(fmt, args...) printk(fmt,## args)
48 #define DPRINTK(fmt, args...)
51 #define FBMON_FIX_HEADER 1
52 #define FBMON_FIX_INPUT 2
53 #define FBMON_FIX_TIMINGS 3
55 #ifdef CONFIG_FB_MODE_HELPERS
62 static const struct broken_edid brokendb[] = {
65 .manufacturer = "DEC",
67 .fix = FBMON_FIX_HEADER,
69 /* ViewSonic PF775a */
71 .manufacturer = "VSC",
73 .fix = FBMON_FIX_INPUT,
77 .manufacturer = "SHP",
79 .fix = FBMON_FIX_TIMINGS,
83 static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
84 0xff, 0xff, 0xff, 0x00
87 static void copy_string(unsigned char *c, unsigned char *s)
91 for (i = 0; (i < 13 && *c != 0x0A); i++)
94 while (i-- && (*--s == 0x20)) *s = 0;
97 static int edid_is_serial_block(unsigned char *block)
99 if ((block[0] == 0x00) && (block[1] == 0x00) &&
100 (block[2] == 0x00) && (block[3] == 0xff) &&
107 static int edid_is_ascii_block(unsigned char *block)
109 if ((block[0] == 0x00) && (block[1] == 0x00) &&
110 (block[2] == 0x00) && (block[3] == 0xfe) &&
117 static int edid_is_limits_block(unsigned char *block)
119 if ((block[0] == 0x00) && (block[1] == 0x00) &&
120 (block[2] == 0x00) && (block[3] == 0xfd) &&
127 static int edid_is_monitor_block(unsigned char *block)
129 if ((block[0] == 0x00) && (block[1] == 0x00) &&
130 (block[2] == 0x00) && (block[3] == 0xfc) &&
137 static int edid_is_timing_block(unsigned char *block)
139 if ((block[0] != 0x00) || (block[1] != 0x00) ||
140 (block[2] != 0x00) || (block[4] != 0x00))
146 static int check_edid(unsigned char *edid)
148 unsigned char *block = edid + ID_MANUFACTURER_NAME, manufacturer[4];
151 int i, fix = 0, ret = 0;
153 manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
154 manufacturer[1] = ((block[0] & 0x03) << 3) +
155 ((block[1] & 0xe0) >> 5) + '@';
156 manufacturer[2] = (block[1] & 0x1f) + '@';
158 model = block[2] + (block[3] << 8);
160 for (i = 0; i < ARRAY_SIZE(brokendb); i++) {
161 if (!strncmp(manufacturer, brokendb[i].manufacturer, 4) &&
162 brokendb[i].model == model) {
163 fix = brokendb[i].fix;
169 case FBMON_FIX_HEADER:
170 for (i = 0; i < 8; i++) {
171 if (edid[i] != edid_v1_header[i]) {
177 case FBMON_FIX_INPUT:
178 b = edid + EDID_STRUCT_DISPLAY;
179 /* Only if display is GTF capable will
180 the input type be reset to analog */
181 if (b[4] & 0x01 && b[0] & 0x80)
184 case FBMON_FIX_TIMINGS:
185 b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
188 for (i = 0; i < 4; i++) {
189 if (edid_is_limits_block(b)) {
194 b += DETAILED_TIMING_DESCRIPTION_SIZE;
201 printk("fbmon: The EDID Block of "
202 "Manufacturer: %s Model: 0x%x is known to "
203 "be broken,\n", manufacturer, model);
208 static void fix_edid(unsigned char *edid, int fix)
211 unsigned char *b, csum = 0;
214 case FBMON_FIX_HEADER:
215 printk("fbmon: trying a header reconstruct\n");
216 memcpy(edid, edid_v1_header, 8);
218 case FBMON_FIX_INPUT:
219 printk("fbmon: trying to fix input type\n");
220 b = edid + EDID_STRUCT_DISPLAY;
224 case FBMON_FIX_TIMINGS:
225 printk("fbmon: trying to fix monitor timings\n");
226 b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
227 for (i = 0; i < 4; i++) {
228 if (!(edid_is_serial_block(b) ||
229 edid_is_ascii_block(b) ||
230 edid_is_monitor_block(b) ||
231 edid_is_timing_block(b))) {
237 b[5] = 60; /* vfmin */
238 b[6] = 60; /* vfmax */
239 b[7] = 30; /* hfmin */
240 b[8] = 75; /* hfmax */
241 b[9] = 17; /* pixclock - 170 MHz*/
246 b += DETAILED_TIMING_DESCRIPTION_SIZE;
249 for (i = 0; i < EDID_LENGTH - 1; i++)
252 edid[127] = 256 - csum;
257 static int edid_checksum(unsigned char *edid)
259 unsigned char i, csum = 0, all_null = 0;
260 int err = 0, fix = check_edid(edid);
265 for (i = 0; i < EDID_LENGTH; i++) {
270 if (csum == 0x00 && all_null) {
271 /* checksum passed, everything's good */
278 static int edid_check_header(unsigned char *edid)
280 int i, err = 1, fix = check_edid(edid);
285 for (i = 0; i < 8; i++) {
286 if (edid[i] != edid_v1_header[i])
293 static void parse_vendor_block(unsigned char *block, struct fb_monspecs *specs)
295 specs->manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
296 specs->manufacturer[1] = ((block[0] & 0x03) << 3) +
297 ((block[1] & 0xe0) >> 5) + '@';
298 specs->manufacturer[2] = (block[1] & 0x1f) + '@';
299 specs->manufacturer[3] = 0;
300 specs->model = block[2] + (block[3] << 8);
301 specs->serial = block[4] + (block[5] << 8) +
302 (block[6] << 16) + (block[7] << 24);
303 specs->year = block[9] + 1990;
304 specs->week = block[8];
305 DPRINTK(" Manufacturer: %s\n", specs->manufacturer);
306 DPRINTK(" Model: %x\n", specs->model);
307 DPRINTK(" Serial#: %u\n", specs->serial);
308 DPRINTK(" Year: %u Week %u\n", specs->year, specs->week);
311 static void get_dpms_capabilities(unsigned char flags,
312 struct fb_monspecs *specs)
315 if (flags & DPMS_ACTIVE_OFF)
316 specs->dpms |= FB_DPMS_ACTIVE_OFF;
317 if (flags & DPMS_SUSPEND)
318 specs->dpms |= FB_DPMS_SUSPEND;
319 if (flags & DPMS_STANDBY)
320 specs->dpms |= FB_DPMS_STANDBY;
321 DPRINTK(" DPMS: Active %s, Suspend %s, Standby %s\n",
322 (flags & DPMS_ACTIVE_OFF) ? "yes" : "no",
323 (flags & DPMS_SUSPEND) ? "yes" : "no",
324 (flags & DPMS_STANDBY) ? "yes" : "no");
327 static void get_chroma(unsigned char *block, struct fb_monspecs *specs)
331 DPRINTK(" Chroma\n");
332 /* Chromaticity data */
333 tmp = ((block[5] & (3 << 6)) >> 6) | (block[0x7] << 2);
336 specs->chroma.redx = tmp/1024;
337 DPRINTK(" RedX: 0.%03d ", specs->chroma.redx);
339 tmp = ((block[5] & (3 << 4)) >> 4) | (block[0x8] << 2);
342 specs->chroma.redy = tmp/1024;
343 DPRINTK("RedY: 0.%03d\n", specs->chroma.redy);
345 tmp = ((block[5] & (3 << 2)) >> 2) | (block[0x9] << 2);
348 specs->chroma.greenx = tmp/1024;
349 DPRINTK(" GreenX: 0.%03d ", specs->chroma.greenx);
351 tmp = (block[5] & 3) | (block[0xa] << 2);
354 specs->chroma.greeny = tmp/1024;
355 DPRINTK("GreenY: 0.%03d\n", specs->chroma.greeny);
357 tmp = ((block[6] & (3 << 6)) >> 6) | (block[0xb] << 2);
360 specs->chroma.bluex = tmp/1024;
361 DPRINTK(" BlueX: 0.%03d ", specs->chroma.bluex);
363 tmp = ((block[6] & (3 << 4)) >> 4) | (block[0xc] << 2);
366 specs->chroma.bluey = tmp/1024;
367 DPRINTK("BlueY: 0.%03d\n", specs->chroma.bluey);
369 tmp = ((block[6] & (3 << 2)) >> 2) | (block[0xd] << 2);
372 specs->chroma.whitex = tmp/1024;
373 DPRINTK(" WhiteX: 0.%03d ", specs->chroma.whitex);
375 tmp = (block[6] & 3) | (block[0xe] << 2);
378 specs->chroma.whitey = tmp/1024;
379 DPRINTK("WhiteY: 0.%03d\n", specs->chroma.whitey);
382 static void calc_mode_timings(int xres, int yres, int refresh,
383 struct fb_videomode *mode)
385 struct fb_var_screeninfo *var;
387 var = kzalloc(sizeof(struct fb_var_screeninfo), GFP_KERNEL);
392 fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON,
396 mode->pixclock = var->pixclock;
397 mode->refresh = refresh;
398 mode->left_margin = var->left_margin;
399 mode->right_margin = var->right_margin;
400 mode->upper_margin = var->upper_margin;
401 mode->lower_margin = var->lower_margin;
402 mode->hsync_len = var->hsync_len;
403 mode->vsync_len = var->vsync_len;
410 static int get_est_timing(unsigned char *block, struct fb_videomode *mode)
417 calc_mode_timings(720, 400, 70, &mode[num]);
418 mode[num++].flag = FB_MODE_IS_CALCULATED;
419 DPRINTK(" 720x400@70Hz\n");
422 calc_mode_timings(720, 400, 88, &mode[num]);
423 mode[num++].flag = FB_MODE_IS_CALCULATED;
424 DPRINTK(" 720x400@88Hz\n");
427 mode[num++] = vesa_modes[3];
428 DPRINTK(" 640x480@60Hz\n");
431 calc_mode_timings(640, 480, 67, &mode[num]);
432 mode[num++].flag = FB_MODE_IS_CALCULATED;
433 DPRINTK(" 640x480@67Hz\n");
436 mode[num++] = vesa_modes[4];
437 DPRINTK(" 640x480@72Hz\n");
440 mode[num++] = vesa_modes[5];
441 DPRINTK(" 640x480@75Hz\n");
444 mode[num++] = vesa_modes[7];
445 DPRINTK(" 800x600@56Hz\n");
448 mode[num++] = vesa_modes[8];
449 DPRINTK(" 800x600@60Hz\n");
454 mode[num++] = vesa_modes[9];
455 DPRINTK(" 800x600@72Hz\n");
458 mode[num++] = vesa_modes[10];
459 DPRINTK(" 800x600@75Hz\n");
462 calc_mode_timings(832, 624, 75, &mode[num]);
463 mode[num++].flag = FB_MODE_IS_CALCULATED;
464 DPRINTK(" 832x624@75Hz\n");
467 mode[num++] = vesa_modes[12];
468 DPRINTK(" 1024x768@87Hz Interlaced\n");
471 mode[num++] = vesa_modes[13];
472 DPRINTK(" 1024x768@60Hz\n");
475 mode[num++] = vesa_modes[14];
476 DPRINTK(" 1024x768@70Hz\n");
479 mode[num++] = vesa_modes[15];
480 DPRINTK(" 1024x768@75Hz\n");
483 mode[num++] = vesa_modes[21];
484 DPRINTK(" 1280x1024@75Hz\n");
488 mode[num++] = vesa_modes[17];
489 DPRINTK(" 1152x870@75Hz\n");
491 DPRINTK(" Manufacturer's mask: %x\n",c&0x7F);
495 static int get_std_timing(unsigned char *block, struct fb_videomode *mode)
497 int xres, yres = 0, refresh, ratio, i;
499 xres = (block[0] + 31) * 8;
503 ratio = (block[1] & 0xc0) >> 6;
515 yres = (xres * 9)/16;
518 refresh = (block[1] & 0x3f) + 60;
520 DPRINTK(" %dx%d@%dHz\n", xres, yres, refresh);
521 for (i = 0; i < VESA_MODEDB_SIZE; i++) {
522 if (vesa_modes[i].xres == xres &&
523 vesa_modes[i].yres == yres &&
524 vesa_modes[i].refresh == refresh) {
525 *mode = vesa_modes[i];
526 mode->flag |= FB_MODE_IS_STANDARD;
530 calc_mode_timings(xres, yres, refresh, mode);
534 static int get_dst_timing(unsigned char *block,
535 struct fb_videomode *mode)
539 for (j = 0; j < 6; j++, block+= STD_TIMING_DESCRIPTION_SIZE)
540 num += get_std_timing(block, &mode[num]);
545 static void get_detailed_timing(unsigned char *block,
546 struct fb_videomode *mode)
548 mode->xres = H_ACTIVE;
549 mode->yres = V_ACTIVE;
550 mode->pixclock = PIXEL_CLOCK;
551 mode->pixclock /= 1000;
552 mode->pixclock = KHZ2PICOS(mode->pixclock);
553 mode->right_margin = H_SYNC_OFFSET;
554 mode->left_margin = (H_ACTIVE + H_BLANKING) -
555 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
556 mode->upper_margin = V_BLANKING - V_SYNC_OFFSET -
558 mode->lower_margin = V_SYNC_OFFSET;
559 mode->hsync_len = H_SYNC_WIDTH;
560 mode->vsync_len = V_SYNC_WIDTH;
562 mode->sync |= FB_SYNC_HOR_HIGH_ACT;
564 mode->sync |= FB_SYNC_VERT_HIGH_ACT;
565 mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *
566 (V_ACTIVE + V_BLANKING));
568 mode->flag = FB_MODE_IS_DETAILED;
570 DPRINTK(" %d MHz ", PIXEL_CLOCK/1000000);
571 DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET,
572 H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING);
573 DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET,
574 V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING);
575 DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-",
576 (VSYNC_POSITIVE) ? "+" : "-");
580 * fb_create_modedb - create video mode database
582 * @dbsize: database size
584 * RETURNS: struct fb_videomode, @dbsize contains length of database
587 * This function builds a mode database using the contents of the EDID
590 static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize)
592 struct fb_videomode *mode, *m;
593 unsigned char *block;
596 mode = kzalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
600 if (edid == NULL || !edid_checksum(edid) ||
601 !edid_check_header(edid)) {
608 DPRINTK(" Detailed Timings\n");
609 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
610 for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
613 if (!(block[0] == 0x00 && block[1] == 0x00)) {
614 get_detailed_timing(block, &mode[num]);
616 mode[num].flag |= FB_MODE_IS_FIRST;
623 DPRINTK(" Supported VESA Modes\n");
624 block = edid + ESTABLISHED_TIMING_1;
625 num += get_est_timing(block, &mode[num]);
627 DPRINTK(" Standard Timings\n");
628 block = edid + STD_TIMING_DESCRIPTIONS_START;
629 for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE)
630 num += get_std_timing(block, &mode[num]);
632 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
633 for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
634 if (block[0] == 0x00 && block[1] == 0x00 && block[3] == 0xfa)
635 num += get_dst_timing(block + 5, &mode[num]);
638 /* Yikes, EDID data is totally useless */
645 m = kmalloc(num * sizeof(struct fb_videomode), GFP_KERNEL);
648 memmove(m, mode, num * sizeof(struct fb_videomode));
654 * fb_destroy_modedb - destroys mode database
655 * @modedb: mode database to destroy
658 * Destroy mode database created by fb_create_modedb
660 void fb_destroy_modedb(struct fb_videomode *modedb)
665 static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
668 unsigned char *block;
670 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
672 DPRINTK(" Monitor Operating Limits: ");
674 for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
675 if (edid_is_limits_block(block)) {
676 specs->hfmin = H_MIN_RATE * 1000;
677 specs->hfmax = H_MAX_RATE * 1000;
678 specs->vfmin = V_MIN_RATE;
679 specs->vfmax = V_MAX_RATE;
680 specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;
681 specs->gtf = (GTF_SUPPORT) ? 1 : 0;
683 DPRINTK("From EDID\n");
688 /* estimate monitor limits based on modes supported */
690 struct fb_videomode *modes, *mode;
691 int num_modes, i, hz, hscan, pixclock;
694 modes = fb_create_modedb(edid, &num_modes);
696 DPRINTK("None Available\n");
701 for (i = 0; i < num_modes; i++) {
703 pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
704 htotal = mode->xres + mode->right_margin + mode->hsync_len
706 vtotal = mode->yres + mode->lower_margin + mode->vsync_len
707 + mode->upper_margin;
709 if (mode->vmode & FB_VMODE_INTERLACED)
712 if (mode->vmode & FB_VMODE_DOUBLE)
715 hscan = (pixclock + htotal / 2) / htotal;
716 hscan = (hscan + 500) / 1000 * 1000;
717 hz = (hscan + vtotal / 2) / vtotal;
719 if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
720 specs->dclkmax = pixclock;
722 if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
723 specs->dclkmin = pixclock;
725 if (specs->hfmax == 0 || specs->hfmax < hscan)
726 specs->hfmax = hscan;
728 if (specs->hfmin == 0 || specs->hfmin > hscan)
729 specs->hfmin = hscan;
731 if (specs->vfmax == 0 || specs->vfmax < hz)
734 if (specs->vfmin == 0 || specs->vfmin > hz)
737 DPRINTK("Extrapolated\n");
738 fb_destroy_modedb(modes);
740 DPRINTK(" H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",
741 specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,
742 specs->vfmax, specs->dclkmax/1000000);
746 static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
748 unsigned char c, *block;
750 block = edid + EDID_STRUCT_DISPLAY;
752 fb_get_monitor_limits(edid, specs);
757 specs->input |= FB_DISP_DDI;
758 DPRINTK(" Digital Display Input");
760 DPRINTK(" Analog Display Input: Input Voltage - ");
761 switch ((block[0] & 0x60) >> 5) {
763 DPRINTK("0.700V/0.300V");
764 specs->input |= FB_DISP_ANA_700_300;
767 DPRINTK("0.714V/0.286V");
768 specs->input |= FB_DISP_ANA_714_286;
771 DPRINTK("1.000V/0.400V");
772 specs->input |= FB_DISP_ANA_1000_400;
775 DPRINTK("0.700V/0.000V");
776 specs->input |= FB_DISP_ANA_700_000;
780 DPRINTK("\n Sync: ");
783 DPRINTK(" Configurable signal level\n");
787 DPRINTK("Blank to Blank ");
788 specs->signal |= FB_SIGNAL_BLANK_BLANK;
791 DPRINTK("Separate ");
792 specs->signal |= FB_SIGNAL_SEPARATE;
795 DPRINTK("Composite ");
796 specs->signal |= FB_SIGNAL_COMPOSITE;
799 DPRINTK("Sync on Green ");
800 specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
803 DPRINTK("Serration on ");
804 specs->signal |= FB_SIGNAL_SERRATION_ON;
807 specs->max_x = block[1];
808 specs->max_y = block[2];
809 DPRINTK(" Max H-size in cm: ");
811 DPRINTK("%d\n", specs->max_x);
813 DPRINTK("variable\n");
814 DPRINTK(" Max V-size in cm: ");
816 DPRINTK("%d\n", specs->max_y);
818 DPRINTK("variable\n");
821 specs->gamma = c+100;
823 DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
825 get_dpms_capabilities(block[4], specs);
827 switch ((block[4] & 0x18) >> 3) {
829 DPRINTK(" Monochrome/Grayscale\n");
830 specs->input |= FB_DISP_MONO;
833 DPRINTK(" RGB Color Display\n");
834 specs->input |= FB_DISP_RGB;
837 DPRINTK(" Non-RGB Multicolor Display\n");
838 specs->input |= FB_DISP_MULTI;
841 DPRINTK(" Unknown\n");
842 specs->input |= FB_DISP_UNKNOWN;
846 get_chroma(block, specs);
851 DPRINTK(" Default color format is primary\n");
852 specs->misc |= FB_MISC_PRIM_COLOR;
855 DPRINTK(" First DETAILED Timing is preferred\n");
856 specs->misc |= FB_MISC_1ST_DETAIL;
859 printk(" Display is GTF capable\n");
864 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
867 unsigned char *block;
869 if (edid == NULL || var == NULL)
872 if (!(edid_checksum(edid)))
875 if (!(edid_check_header(edid)))
878 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
880 for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
881 if (edid_is_timing_block(block)) {
882 var->xres = var->xres_virtual = H_ACTIVE;
883 var->yres = var->yres_virtual = V_ACTIVE;
884 var->height = var->width = -1;
885 var->right_margin = H_SYNC_OFFSET;
886 var->left_margin = (H_ACTIVE + H_BLANKING) -
887 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
888 var->upper_margin = V_BLANKING - V_SYNC_OFFSET -
890 var->lower_margin = V_SYNC_OFFSET;
891 var->hsync_len = H_SYNC_WIDTH;
892 var->vsync_len = V_SYNC_WIDTH;
893 var->pixclock = PIXEL_CLOCK;
894 var->pixclock /= 1000;
895 var->pixclock = KHZ2PICOS(var->pixclock);
898 var->sync |= FB_SYNC_HOR_HIGH_ACT;
900 var->sync |= FB_SYNC_VERT_HIGH_ACT;
907 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
909 unsigned char *block;
915 if (!(edid_checksum(edid)))
918 if (!(edid_check_header(edid)))
921 memset(specs, 0, sizeof(struct fb_monspecs));
923 specs->version = edid[EDID_STRUCT_VERSION];
924 specs->revision = edid[EDID_STRUCT_REVISION];
926 DPRINTK("========================================\n");
927 DPRINTK("Display Information (EDID)\n");
928 DPRINTK("========================================\n");
929 DPRINTK(" EDID Version %d.%d\n", (int) specs->version,
930 (int) specs->revision);
932 parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);
934 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
935 for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
936 if (edid_is_serial_block(block)) {
937 copy_string(block, specs->serial_no);
938 DPRINTK(" Serial Number: %s\n", specs->serial_no);
939 } else if (edid_is_ascii_block(block)) {
940 copy_string(block, specs->ascii);
941 DPRINTK(" ASCII Block: %s\n", specs->ascii);
942 } else if (edid_is_monitor_block(block)) {
943 copy_string(block, specs->monitor);
944 DPRINTK(" Monitor Name: %s\n", specs->monitor);
948 DPRINTK(" Display Characteristics:\n");
949 get_monspecs(edid, specs);
951 specs->modedb = fb_create_modedb(edid, &specs->modedb_len);
954 * Workaround for buggy EDIDs that sets that the first
955 * detailed timing is preferred but has not detailed
958 for (i = 0; i < specs->modedb_len; i++) {
959 if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {
966 specs->misc &= ~FB_MISC_1ST_DETAIL;
968 DPRINTK("========================================\n");
972 * VESA Generalized Timing Formula (GTF)
976 #define V_FRONTPORCH 1
978 #define H_SCALEFACTOR 20
979 #define H_BLANKSCALE 128
980 #define H_GRADIENT 600
984 struct __fb_timings {
997 * fb_get_vblank - get vertical blank time
998 * @hfreq: horizontal freq
1001 * vblank = right_margin + vsync_len + left_margin
1003 * given: right_margin = 1 (V_FRONTPORCH)
1008 * left_margin = --------------- - vsync_len
1011 static u32 fb_get_vblank(u32 hfreq)
1015 vblank = (hfreq * FLYBACK)/1000;
1016 vblank = (vblank + 500)/1000;
1017 return (vblank + V_FRONTPORCH);
1021 * fb_get_hblank_by_freq - get horizontal blank time given hfreq
1022 * @hfreq: horizontal freq
1023 * @xres: horizontal resolution in pixels
1028 * hblank = ------------------
1031 * duty cycle = percent of htotal assigned to inactive display
1032 * duty cycle = C - (M/Hfreq)
1034 * where: C = ((offset - scale factor) * blank_scale)
1035 * -------------------------------------- + scale factor
1037 * M = blank_scale * gradient
1040 static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
1042 u32 c_val, m_val, duty_cycle, hblank;
1044 c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 +
1045 H_SCALEFACTOR) * 1000;
1046 m_val = (H_BLANKSCALE * H_GRADIENT)/256;
1047 m_val = (m_val * 1000000)/hfreq;
1048 duty_cycle = c_val - m_val;
1049 hblank = (xres * duty_cycle)/(100000 - duty_cycle);
1054 * fb_get_hblank_by_dclk - get horizontal blank time given pixelclock
1055 * @dclk: pixelclock in Hz
1056 * @xres: horizontal resolution in pixels
1061 * hblank = ------------------
1064 * duty cycle = percent of htotal assigned to inactive display
1065 * duty cycle = C - (M * h_period)
1067 * where: h_period = SQRT(100 - C + (0.4 * xres * M)/dclk) + C - 100
1068 * -----------------------------------------------
1074 static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)
1076 u32 duty_cycle, h_period, hblank;
1079 h_period = 100 - C_VAL;
1080 h_period *= h_period;
1081 h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);
1084 h_period = int_sqrt(h_period);
1085 h_period -= (100 - C_VAL) * 100;
1087 h_period /= 2 * M_VAL;
1089 duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;
1090 hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;
1096 * fb_get_hfreq - estimate hsync
1097 * @vfreq: vertical refresh rate
1098 * @yres: vertical resolution
1102 * (yres + front_port) * vfreq * 1000000
1103 * hfreq = -------------------------------------
1104 * (1000000 - (vfreq * FLYBACK)
1108 static u32 fb_get_hfreq(u32 vfreq, u32 yres)
1112 divisor = (1000000 - (vfreq * FLYBACK))/1000;
1113 hfreq = (yres + V_FRONTPORCH) * vfreq * 1000;
1114 return (hfreq/divisor);
1117 static void fb_timings_vfreq(struct __fb_timings *timings)
1119 timings->hfreq = fb_get_hfreq(timings->vfreq, timings->vactive);
1120 timings->vblank = fb_get_vblank(timings->hfreq);
1121 timings->vtotal = timings->vactive + timings->vblank;
1122 timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1124 timings->htotal = timings->hactive + timings->hblank;
1125 timings->dclk = timings->htotal * timings->hfreq;
1128 static void fb_timings_hfreq(struct __fb_timings *timings)
1130 timings->vblank = fb_get_vblank(timings->hfreq);
1131 timings->vtotal = timings->vactive + timings->vblank;
1132 timings->vfreq = timings->hfreq/timings->vtotal;
1133 timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1135 timings->htotal = timings->hactive + timings->hblank;
1136 timings->dclk = timings->htotal * timings->hfreq;
1139 static void fb_timings_dclk(struct __fb_timings *timings)
1141 timings->hblank = fb_get_hblank_by_dclk(timings->dclk,
1143 timings->htotal = timings->hactive + timings->hblank;
1144 timings->hfreq = timings->dclk/timings->htotal;
1145 timings->vblank = fb_get_vblank(timings->hfreq);
1146 timings->vtotal = timings->vactive + timings->vblank;
1147 timings->vfreq = timings->hfreq/timings->vtotal;
1151 * fb_get_mode - calculates video mode using VESA GTF
1152 * @flags: if: 0 - maximize vertical refresh rate
1153 * 1 - vrefresh-driven calculation;
1154 * 2 - hscan-driven calculation;
1155 * 3 - pixelclock-driven calculation;
1156 * @val: depending on @flags, ignored, vrefresh, hsync or pixelclock
1157 * @var: pointer to fb_var_screeninfo
1158 * @info: pointer to fb_info
1161 * Calculates video mode based on monitor specs using VESA GTF.
1162 * The GTF is best for VESA GTF compliant monitors but is
1163 * specifically formulated to work for older monitors as well.
1165 * If @flag==0, the function will attempt to maximize the
1166 * refresh rate. Otherwise, it will calculate timings based on
1167 * the flag and accompanying value.
1169 * If FB_IGNOREMON bit is set in @flags, monitor specs will be
1170 * ignored and @var will be filled with the calculated timings.
1172 * All calculations are based on the VESA GTF Spreadsheet
1173 * available at VESA's public ftp (http://www.vesa.org).
1176 * The timings generated by the GTF will be different from VESA
1177 * DMT. It might be a good idea to keep a table of standard
1178 * VESA modes as well. The GTF may also not work for some displays,
1179 * such as, and especially, analog TV.
1182 * A valid info->monspecs, otherwise 'safe numbers' will be used.
1184 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)
1186 struct __fb_timings *timings;
1187 u32 interlace = 1, dscan = 1;
1188 u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;
1191 timings = kzalloc(sizeof(struct __fb_timings), GFP_KERNEL);
1197 * If monspecs are invalid, use values that are enough
1200 if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||
1201 !info->monspecs.dclkmax ||
1202 info->monspecs.hfmax < info->monspecs.hfmin ||
1203 info->monspecs.vfmax < info->monspecs.vfmin ||
1204 info->monspecs.dclkmax < info->monspecs.dclkmin) {
1205 hfmin = 29000; hfmax = 30000;
1206 vfmin = 60; vfmax = 60;
1207 dclkmin = 0; dclkmax = 25000000;
1209 hfmin = info->monspecs.hfmin;
1210 hfmax = info->monspecs.hfmax;
1211 vfmin = info->monspecs.vfmin;
1212 vfmax = info->monspecs.vfmax;
1213 dclkmin = info->monspecs.dclkmin;
1214 dclkmax = info->monspecs.dclkmax;
1217 timings->hactive = var->xres;
1218 timings->vactive = var->yres;
1219 if (var->vmode & FB_VMODE_INTERLACED) {
1220 timings->vactive /= 2;
1223 if (var->vmode & FB_VMODE_DOUBLE) {
1224 timings->vactive *= 2;
1228 switch (flags & ~FB_IGNOREMON) {
1229 case FB_MAXTIMINGS: /* maximize refresh rate */
1230 timings->hfreq = hfmax;
1231 fb_timings_hfreq(timings);
1232 if (timings->vfreq > vfmax) {
1233 timings->vfreq = vfmax;
1234 fb_timings_vfreq(timings);
1236 if (timings->dclk > dclkmax) {
1237 timings->dclk = dclkmax;
1238 fb_timings_dclk(timings);
1241 case FB_VSYNCTIMINGS: /* vrefresh driven */
1242 timings->vfreq = val;
1243 fb_timings_vfreq(timings);
1245 case FB_HSYNCTIMINGS: /* hsync driven */
1246 timings->hfreq = val;
1247 fb_timings_hfreq(timings);
1249 case FB_DCLKTIMINGS: /* pixelclock driven */
1250 timings->dclk = PICOS2KHZ(val) * 1000;
1251 fb_timings_dclk(timings);
1258 if (err || (!(flags & FB_IGNOREMON) &&
1259 (timings->vfreq < vfmin || timings->vfreq > vfmax ||
1260 timings->hfreq < hfmin || timings->hfreq > hfmax ||
1261 timings->dclk < dclkmin || timings->dclk > dclkmax))) {
1264 var->pixclock = KHZ2PICOS(timings->dclk/1000);
1265 var->hsync_len = (timings->htotal * 8)/100;
1266 var->right_margin = (timings->hblank/2) - var->hsync_len;
1267 var->left_margin = timings->hblank - var->right_margin -
1269 var->vsync_len = (3 * interlace)/dscan;
1270 var->lower_margin = (1 * interlace)/dscan;
1271 var->upper_margin = (timings->vblank * interlace)/dscan -
1272 (var->vsync_len + var->lower_margin);
1279 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
1283 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1287 void fb_destroy_modedb(struct fb_videomode *modedb)
1290 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
1291 struct fb_info *info)
1295 #endif /* CONFIG_FB_MODE_HELPERS */
1298 * fb_validate_mode - validates var against monitor capabilities
1299 * @var: pointer to fb_var_screeninfo
1300 * @info: pointer to fb_info
1303 * Validates video mode against monitor capabilities specified in
1307 * A valid info->monspecs.
1309 int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
1311 u32 hfreq, vfreq, htotal, vtotal, pixclock;
1312 u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
1315 * If monspecs are invalid, use values that are enough
1318 if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
1319 !info->monspecs.dclkmax ||
1320 info->monspecs.hfmax < info->monspecs.hfmin ||
1321 info->monspecs.vfmax < info->monspecs.vfmin ||
1322 info->monspecs.dclkmax < info->monspecs.dclkmin) {
1323 hfmin = 29000; hfmax = 30000;
1324 vfmin = 60; vfmax = 60;
1325 dclkmin = 0; dclkmax = 25000000;
1327 hfmin = info->monspecs.hfmin;
1328 hfmax = info->monspecs.hfmax;
1329 vfmin = info->monspecs.vfmin;
1330 vfmax = info->monspecs.vfmax;
1331 dclkmin = info->monspecs.dclkmin;
1332 dclkmax = info->monspecs.dclkmax;
1337 pixclock = PICOS2KHZ(var->pixclock) * 1000;
1339 htotal = var->xres + var->right_margin + var->hsync_len +
1341 vtotal = var->yres + var->lower_margin + var->vsync_len +
1344 if (var->vmode & FB_VMODE_INTERLACED)
1346 if (var->vmode & FB_VMODE_DOUBLE)
1349 hfreq = pixclock/htotal;
1350 hfreq = (hfreq + 500) / 1000 * 1000;
1352 vfreq = hfreq/vtotal;
1354 return (vfreq < vfmin || vfreq > vfmax ||
1355 hfreq < hfmin || hfreq > hfmax ||
1356 pixclock < dclkmin || pixclock > dclkmax) ?
1360 #if defined(CONFIG_FIRMWARE_EDID) && defined(CONFIG_X86)
1363 * We need to ensure that the EDID block is only returned for
1364 * the primary graphics adapter.
1367 const unsigned char *fb_firmware_edid(struct device *device)
1369 struct pci_dev *dev = NULL;
1370 struct resource *res = NULL;
1371 unsigned char *edid = NULL;
1374 dev = to_pci_dev(device);
1377 res = &dev->resource[PCI_ROM_RESOURCE];
1379 if (res && res->flags & IORESOURCE_ROM_SHADOW)
1380 edid = edid_info.dummy;
1385 const unsigned char *fb_firmware_edid(struct device *device)
1390 EXPORT_SYMBOL(fb_firmware_edid);
1392 EXPORT_SYMBOL(fb_parse_edid);
1393 EXPORT_SYMBOL(fb_edid_to_monspecs);
1394 EXPORT_SYMBOL(fb_get_mode);
1395 EXPORT_SYMBOL(fb_validate_mode);
1396 EXPORT_SYMBOL(fb_destroy_modedb);