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
29 #include <linux/tty.h>
31 #include <linux/module.h>
32 #include <video/edid.h>
34 #include <linux/pci.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
55 #ifdef CONFIG_FB_MODE_HELPERS
62 static struct broken_edid brokendb[] = {
65 .manufacturer = "DEC",
67 .fix = FBMON_FIX_HEADER,
69 /* ViewSonic PF775a */
71 .manufacturer = "VSC",
73 .fix = FBMON_FIX_INPUT,
77 static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
78 0xff, 0xff, 0xff, 0x00
81 static void copy_string(unsigned char *c, unsigned char *s)
85 for (i = 0; (i < 13 && *c != 0x0A); i++)
88 while (i-- && (*--s == 0x20)) *s = 0;
91 static int check_edid(unsigned char *edid)
93 unsigned char *block = edid + ID_MANUFACTURER_NAME, manufacturer[4];
96 int i, fix = 0, ret = 0;
98 manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
99 manufacturer[1] = ((block[0] & 0x03) << 3) +
100 ((block[1] & 0xe0) >> 5) + '@';
101 manufacturer[2] = (block[1] & 0x1f) + '@';
103 model = block[2] + (block[3] << 8);
105 for (i = 0; i < ARRAY_SIZE(brokendb); i++) {
106 if (!strncmp(manufacturer, brokendb[i].manufacturer, 4) &&
107 brokendb[i].model == model) {
108 printk("fbmon: The EDID Block of "
109 "Manufacturer: %s Model: 0x%x is known to "
110 "be broken,\n", manufacturer, model);
111 fix = brokendb[i].fix;
117 case FBMON_FIX_HEADER:
118 for (i = 0; i < 8; i++) {
119 if (edid[i] != edid_v1_header[i])
123 case FBMON_FIX_INPUT:
124 b = edid + EDID_STRUCT_DISPLAY;
125 /* Only if display is GTF capable will
126 the input type be reset to analog */
127 if (b[4] & 0x01 && b[0] & 0x80)
135 static void fix_edid(unsigned char *edid, int fix)
140 case FBMON_FIX_HEADER:
141 printk("fbmon: trying a header reconstruct\n");
142 memcpy(edid, edid_v1_header, 8);
144 case FBMON_FIX_INPUT:
145 printk("fbmon: trying to fix input type\n");
146 b = edid + EDID_STRUCT_DISPLAY;
152 static int edid_checksum(unsigned char *edid)
154 unsigned char i, csum = 0, all_null = 0;
155 int err = 0, fix = check_edid(edid);
160 for (i = 0; i < EDID_LENGTH; i++) {
165 if (csum == 0x00 && all_null) {
166 /* checksum passed, everything's good */
173 static int edid_check_header(unsigned char *edid)
175 int i, err = 1, fix = check_edid(edid);
180 for (i = 0; i < 8; i++) {
181 if (edid[i] != edid_v1_header[i])
188 static void parse_vendor_block(unsigned char *block, struct fb_monspecs *specs)
190 specs->manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
191 specs->manufacturer[1] = ((block[0] & 0x03) << 3) +
192 ((block[1] & 0xe0) >> 5) + '@';
193 specs->manufacturer[2] = (block[1] & 0x1f) + '@';
194 specs->manufacturer[3] = 0;
195 specs->model = block[2] + (block[3] << 8);
196 specs->serial = block[4] + (block[5] << 8) +
197 (block[6] << 16) + (block[7] << 24);
198 specs->year = block[9] + 1990;
199 specs->week = block[8];
200 DPRINTK(" Manufacturer: %s\n", specs->manufacturer);
201 DPRINTK(" Model: %x\n", specs->model);
202 DPRINTK(" Serial#: %u\n", specs->serial);
203 DPRINTK(" Year: %u Week %u\n", specs->year, specs->week);
206 static void get_dpms_capabilities(unsigned char flags,
207 struct fb_monspecs *specs)
210 if (flags & DPMS_ACTIVE_OFF)
211 specs->dpms |= FB_DPMS_ACTIVE_OFF;
212 if (flags & DPMS_SUSPEND)
213 specs->dpms |= FB_DPMS_SUSPEND;
214 if (flags & DPMS_STANDBY)
215 specs->dpms |= FB_DPMS_STANDBY;
216 DPRINTK(" DPMS: Active %s, Suspend %s, Standby %s\n",
217 (flags & DPMS_ACTIVE_OFF) ? "yes" : "no",
218 (flags & DPMS_SUSPEND) ? "yes" : "no",
219 (flags & DPMS_STANDBY) ? "yes" : "no");
222 static void get_chroma(unsigned char *block, struct fb_monspecs *specs)
226 DPRINTK(" Chroma\n");
227 /* Chromaticity data */
228 tmp = ((block[5] & (3 << 6)) >> 6) | (block[0x7] << 2);
231 specs->chroma.redx = tmp/1024;
232 DPRINTK(" RedX: 0.%03d ", specs->chroma.redx);
234 tmp = ((block[5] & (3 << 4)) >> 4) | (block[0x8] << 2);
237 specs->chroma.redy = tmp/1024;
238 DPRINTK("RedY: 0.%03d\n", specs->chroma.redy);
240 tmp = ((block[5] & (3 << 2)) >> 2) | (block[0x9] << 2);
243 specs->chroma.greenx = tmp/1024;
244 DPRINTK(" GreenX: 0.%03d ", specs->chroma.greenx);
246 tmp = (block[5] & 3) | (block[0xa] << 2);
249 specs->chroma.greeny = tmp/1024;
250 DPRINTK("GreenY: 0.%03d\n", specs->chroma.greeny);
252 tmp = ((block[6] & (3 << 6)) >> 6) | (block[0xb] << 2);
255 specs->chroma.bluex = tmp/1024;
256 DPRINTK(" BlueX: 0.%03d ", specs->chroma.bluex);
258 tmp = ((block[6] & (3 << 4)) >> 4) | (block[0xc] << 2);
261 specs->chroma.bluey = tmp/1024;
262 DPRINTK("BlueY: 0.%03d\n", specs->chroma.bluey);
264 tmp = ((block[6] & (3 << 2)) >> 2) | (block[0xd] << 2);
267 specs->chroma.whitex = tmp/1024;
268 DPRINTK(" WhiteX: 0.%03d ", specs->chroma.whitex);
270 tmp = (block[6] & 3) | (block[0xe] << 2);
273 specs->chroma.whitey = tmp/1024;
274 DPRINTK("WhiteY: 0.%03d\n", specs->chroma.whitey);
277 static int edid_is_serial_block(unsigned char *block)
279 if ((block[0] == 0x00) && (block[1] == 0x00) &&
280 (block[2] == 0x00) && (block[3] == 0xff) &&
287 static int edid_is_ascii_block(unsigned char *block)
289 if ((block[0] == 0x00) && (block[1] == 0x00) &&
290 (block[2] == 0x00) && (block[3] == 0xfe) &&
297 static int edid_is_limits_block(unsigned char *block)
299 if ((block[0] == 0x00) && (block[1] == 0x00) &&
300 (block[2] == 0x00) && (block[3] == 0xfd) &&
307 static int edid_is_monitor_block(unsigned char *block)
309 if ((block[0] == 0x00) && (block[1] == 0x00) &&
310 (block[2] == 0x00) && (block[3] == 0xfc) &&
317 static void calc_mode_timings(int xres, int yres, int refresh,
318 struct fb_videomode *mode)
320 struct fb_var_screeninfo *var;
322 var = kzalloc(sizeof(struct fb_var_screeninfo), GFP_KERNEL);
327 fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON,
331 mode->pixclock = var->pixclock;
332 mode->refresh = refresh;
333 mode->left_margin = var->left_margin;
334 mode->right_margin = var->right_margin;
335 mode->upper_margin = var->upper_margin;
336 mode->lower_margin = var->lower_margin;
337 mode->hsync_len = var->hsync_len;
338 mode->vsync_len = var->vsync_len;
345 static int get_est_timing(unsigned char *block, struct fb_videomode *mode)
352 calc_mode_timings(720, 400, 70, &mode[num]);
353 mode[num++].flag = FB_MODE_IS_CALCULATED;
354 DPRINTK(" 720x400@70Hz\n");
357 calc_mode_timings(720, 400, 88, &mode[num]);
358 mode[num++].flag = FB_MODE_IS_CALCULATED;
359 DPRINTK(" 720x400@88Hz\n");
362 mode[num++] = vesa_modes[3];
363 DPRINTK(" 640x480@60Hz\n");
366 calc_mode_timings(640, 480, 67, &mode[num]);
367 mode[num++].flag = FB_MODE_IS_CALCULATED;
368 DPRINTK(" 640x480@67Hz\n");
371 mode[num++] = vesa_modes[4];
372 DPRINTK(" 640x480@72Hz\n");
375 mode[num++] = vesa_modes[5];
376 DPRINTK(" 640x480@75Hz\n");
379 mode[num++] = vesa_modes[7];
380 DPRINTK(" 800x600@56Hz\n");
383 mode[num++] = vesa_modes[8];
384 DPRINTK(" 800x600@60Hz\n");
389 mode[num++] = vesa_modes[9];
390 DPRINTK(" 800x600@72Hz\n");
393 mode[num++] = vesa_modes[10];
394 DPRINTK(" 800x600@75Hz\n");
397 calc_mode_timings(832, 624, 75, &mode[num]);
398 mode[num++].flag = FB_MODE_IS_CALCULATED;
399 DPRINTK(" 832x624@75Hz\n");
402 mode[num++] = vesa_modes[12];
403 DPRINTK(" 1024x768@87Hz Interlaced\n");
406 mode[num++] = vesa_modes[13];
407 DPRINTK(" 1024x768@60Hz\n");
410 mode[num++] = vesa_modes[14];
411 DPRINTK(" 1024x768@70Hz\n");
414 mode[num++] = vesa_modes[15];
415 DPRINTK(" 1024x768@75Hz\n");
418 mode[num++] = vesa_modes[21];
419 DPRINTK(" 1280x1024@75Hz\n");
423 mode[num++] = vesa_modes[17];
424 DPRINTK(" 1152x870@75Hz\n");
426 DPRINTK(" Manufacturer's mask: %x\n",c&0x7F);
430 static int get_std_timing(unsigned char *block, struct fb_videomode *mode)
432 int xres, yres = 0, refresh, ratio, i;
434 xres = (block[0] + 31) * 8;
438 ratio = (block[1] & 0xc0) >> 6;
450 yres = (xres * 9)/16;
453 refresh = (block[1] & 0x3f) + 60;
455 DPRINTK(" %dx%d@%dHz\n", xres, yres, refresh);
456 for (i = 0; i < VESA_MODEDB_SIZE; i++) {
457 if (vesa_modes[i].xres == xres &&
458 vesa_modes[i].yres == yres &&
459 vesa_modes[i].refresh == refresh) {
460 *mode = vesa_modes[i];
461 mode->flag |= FB_MODE_IS_STANDARD;
465 calc_mode_timings(xres, yres, refresh, mode);
469 static int get_dst_timing(unsigned char *block,
470 struct fb_videomode *mode)
474 for (j = 0; j < 6; j++, block+= STD_TIMING_DESCRIPTION_SIZE)
475 num += get_std_timing(block, &mode[num]);
480 static void get_detailed_timing(unsigned char *block,
481 struct fb_videomode *mode)
483 mode->xres = H_ACTIVE;
484 mode->yres = V_ACTIVE;
485 mode->pixclock = PIXEL_CLOCK;
486 mode->pixclock /= 1000;
487 mode->pixclock = KHZ2PICOS(mode->pixclock);
488 mode->right_margin = H_SYNC_OFFSET;
489 mode->left_margin = (H_ACTIVE + H_BLANKING) -
490 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
491 mode->upper_margin = V_BLANKING - V_SYNC_OFFSET -
493 mode->lower_margin = V_SYNC_OFFSET;
494 mode->hsync_len = H_SYNC_WIDTH;
495 mode->vsync_len = V_SYNC_WIDTH;
497 mode->sync |= FB_SYNC_HOR_HIGH_ACT;
499 mode->sync |= FB_SYNC_VERT_HIGH_ACT;
500 mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *
501 (V_ACTIVE + V_BLANKING));
503 mode->flag = FB_MODE_IS_DETAILED;
505 DPRINTK(" %d MHz ", PIXEL_CLOCK/1000000);
506 DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET,
507 H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING);
508 DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET,
509 V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING);
510 DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-",
511 (VSYNC_POSITIVE) ? "+" : "-");
515 * fb_create_modedb - create video mode database
517 * @dbsize: database size
519 * RETURNS: struct fb_videomode, @dbsize contains length of database
522 * This function builds a mode database using the contents of the EDID
525 static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize)
527 struct fb_videomode *mode, *m;
528 unsigned char *block;
531 mode = kmalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
534 memset(mode, 0, 50 * sizeof(struct fb_videomode));
536 if (edid == NULL || !edid_checksum(edid) ||
537 !edid_check_header(edid)) {
544 DPRINTK(" Detailed Timings\n");
545 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
546 for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
549 if (!(block[0] == 0x00 && block[1] == 0x00)) {
550 get_detailed_timing(block, &mode[num]);
552 mode[num].flag |= FB_MODE_IS_FIRST;
559 DPRINTK(" Supported VESA Modes\n");
560 block = edid + ESTABLISHED_TIMING_1;
561 num += get_est_timing(block, &mode[num]);
563 DPRINTK(" Standard Timings\n");
564 block = edid + STD_TIMING_DESCRIPTIONS_START;
565 for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE)
566 num += get_std_timing(block, &mode[num]);
568 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
569 for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
570 if (block[0] == 0x00 && block[1] == 0x00 && block[3] == 0xfa)
571 num += get_dst_timing(block + 5, &mode[num]);
574 /* Yikes, EDID data is totally useless */
581 m = kmalloc(num * sizeof(struct fb_videomode), GFP_KERNEL);
584 memmove(m, mode, num * sizeof(struct fb_videomode));
590 * fb_destroy_modedb - destroys mode database
591 * @modedb: mode database to destroy
594 * Destroy mode database created by fb_create_modedb
596 void fb_destroy_modedb(struct fb_videomode *modedb)
601 static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
604 unsigned char *block;
606 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
608 DPRINTK(" Monitor Operating Limits: ");
609 for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
610 if (edid_is_limits_block(block)) {
611 specs->hfmin = H_MIN_RATE * 1000;
612 specs->hfmax = H_MAX_RATE * 1000;
613 specs->vfmin = V_MIN_RATE;
614 specs->vfmax = V_MAX_RATE;
615 specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;
616 specs->gtf = (GTF_SUPPORT) ? 1 : 0;
618 DPRINTK("From EDID\n");
623 /* estimate monitor limits based on modes supported */
625 struct fb_videomode *modes;
626 int num_modes, i, hz, hscan, pixclock;
628 modes = fb_create_modedb(edid, &num_modes);
630 DPRINTK("None Available\n");
635 for (i = 0; i < num_modes; i++) {
636 hz = modes[i].refresh;
637 pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
638 hscan = (modes[i].yres * 105 * hz + 5000)/100;
640 if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
641 specs->dclkmax = pixclock;
642 if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
643 specs->dclkmin = pixclock;
644 if (specs->hfmax == 0 || specs->hfmax < hscan)
645 specs->hfmax = hscan;
646 if (specs->hfmin == 0 || specs->hfmin > hscan)
647 specs->hfmin = hscan;
648 if (specs->vfmax == 0 || specs->vfmax < hz)
650 if (specs->vfmin == 0 || specs->vfmin > hz)
653 DPRINTK("Extrapolated\n");
654 fb_destroy_modedb(modes);
656 DPRINTK(" H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",
657 specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,
658 specs->vfmax, specs->dclkmax/1000000);
662 static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
664 unsigned char c, *block;
666 block = edid + EDID_STRUCT_DISPLAY;
668 fb_get_monitor_limits(edid, specs);
673 specs->input |= FB_DISP_DDI;
674 DPRINTK(" Digital Display Input");
676 DPRINTK(" Analog Display Input: Input Voltage - ");
677 switch ((block[0] & 0x60) >> 5) {
679 DPRINTK("0.700V/0.300V");
680 specs->input |= FB_DISP_ANA_700_300;
683 DPRINTK("0.714V/0.286V");
684 specs->input |= FB_DISP_ANA_714_286;
687 DPRINTK("1.000V/0.400V");
688 specs->input |= FB_DISP_ANA_1000_400;
691 DPRINTK("0.700V/0.000V");
692 specs->input |= FB_DISP_ANA_700_000;
696 DPRINTK("\n Sync: ");
699 DPRINTK(" Configurable signal level\n");
703 DPRINTK("Blank to Blank ");
704 specs->signal |= FB_SIGNAL_BLANK_BLANK;
707 DPRINTK("Separate ");
708 specs->signal |= FB_SIGNAL_SEPARATE;
711 DPRINTK("Composite ");
712 specs->signal |= FB_SIGNAL_COMPOSITE;
715 DPRINTK("Sync on Green ");
716 specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
719 DPRINTK("Serration on ");
720 specs->signal |= FB_SIGNAL_SERRATION_ON;
723 specs->max_x = block[1];
724 specs->max_y = block[2];
725 DPRINTK(" Max H-size in cm: ");
727 DPRINTK("%d\n", specs->max_x);
729 DPRINTK("variable\n");
730 DPRINTK(" Max V-size in cm: ");
732 DPRINTK("%d\n", specs->max_y);
734 DPRINTK("variable\n");
737 specs->gamma = c+100;
739 DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
741 get_dpms_capabilities(block[4], specs);
743 switch ((block[4] & 0x18) >> 3) {
745 DPRINTK(" Monochrome/Grayscale\n");
746 specs->input |= FB_DISP_MONO;
749 DPRINTK(" RGB Color Display\n");
750 specs->input |= FB_DISP_RGB;
753 DPRINTK(" Non-RGB Multicolor Display\n");
754 specs->input |= FB_DISP_MULTI;
757 DPRINTK(" Unknown\n");
758 specs->input |= FB_DISP_UNKNOWN;
762 get_chroma(block, specs);
767 DPRINTK(" Default color format is primary\n");
768 specs->misc |= FB_MISC_PRIM_COLOR;
771 DPRINTK(" First DETAILED Timing is preferred\n");
772 specs->misc |= FB_MISC_1ST_DETAIL;
775 printk(" Display is GTF capable\n");
780 static int edid_is_timing_block(unsigned char *block)
782 if ((block[0] != 0x00) || (block[1] != 0x00) ||
783 (block[2] != 0x00) || (block[4] != 0x00))
789 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
792 unsigned char *block;
794 if (edid == NULL || var == NULL)
797 if (!(edid_checksum(edid)))
800 if (!(edid_check_header(edid)))
803 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
805 for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
806 if (edid_is_timing_block(block)) {
807 var->xres = var->xres_virtual = H_ACTIVE;
808 var->yres = var->yres_virtual = V_ACTIVE;
809 var->height = var->width = -1;
810 var->right_margin = H_SYNC_OFFSET;
811 var->left_margin = (H_ACTIVE + H_BLANKING) -
812 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
813 var->upper_margin = V_BLANKING - V_SYNC_OFFSET -
815 var->lower_margin = V_SYNC_OFFSET;
816 var->hsync_len = H_SYNC_WIDTH;
817 var->vsync_len = V_SYNC_WIDTH;
818 var->pixclock = PIXEL_CLOCK;
819 var->pixclock /= 1000;
820 var->pixclock = KHZ2PICOS(var->pixclock);
823 var->sync |= FB_SYNC_HOR_HIGH_ACT;
825 var->sync |= FB_SYNC_VERT_HIGH_ACT;
832 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
834 unsigned char *block;
840 if (!(edid_checksum(edid)))
843 if (!(edid_check_header(edid)))
846 memset(specs, 0, sizeof(struct fb_monspecs));
848 specs->version = edid[EDID_STRUCT_VERSION];
849 specs->revision = edid[EDID_STRUCT_REVISION];
851 DPRINTK("========================================\n");
852 DPRINTK("Display Information (EDID)\n");
853 DPRINTK("========================================\n");
854 DPRINTK(" EDID Version %d.%d\n", (int) specs->version,
855 (int) specs->revision);
857 parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);
859 block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
860 for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
861 if (edid_is_serial_block(block)) {
862 copy_string(block, specs->serial_no);
863 DPRINTK(" Serial Number: %s\n", specs->serial_no);
864 } else if (edid_is_ascii_block(block)) {
865 copy_string(block, specs->ascii);
866 DPRINTK(" ASCII Block: %s\n", specs->ascii);
867 } else if (edid_is_monitor_block(block)) {
868 copy_string(block, specs->monitor);
869 DPRINTK(" Monitor Name: %s\n", specs->monitor);
873 DPRINTK(" Display Characteristics:\n");
874 get_monspecs(edid, specs);
876 specs->modedb = fb_create_modedb(edid, &specs->modedb_len);
879 * Workaround for buggy EDIDs that sets that the first
880 * detailed timing is preferred but has not detailed
883 for (i = 0; i < specs->modedb_len; i++) {
884 if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {
891 specs->misc &= ~FB_MISC_1ST_DETAIL;
893 DPRINTK("========================================\n");
897 * VESA Generalized Timing Formula (GTF)
901 #define V_FRONTPORCH 1
903 #define H_SCALEFACTOR 20
904 #define H_BLANKSCALE 128
905 #define H_GRADIENT 600
909 struct __fb_timings {
922 * fb_get_vblank - get vertical blank time
923 * @hfreq: horizontal freq
926 * vblank = right_margin + vsync_len + left_margin
928 * given: right_margin = 1 (V_FRONTPORCH)
933 * left_margin = --------------- - vsync_len
936 static u32 fb_get_vblank(u32 hfreq)
940 vblank = (hfreq * FLYBACK)/1000;
941 vblank = (vblank + 500)/1000;
942 return (vblank + V_FRONTPORCH);
946 * fb_get_hblank_by_freq - get horizontal blank time given hfreq
947 * @hfreq: horizontal freq
948 * @xres: horizontal resolution in pixels
953 * hblank = ------------------
956 * duty cycle = percent of htotal assigned to inactive display
957 * duty cycle = C - (M/Hfreq)
959 * where: C = ((offset - scale factor) * blank_scale)
960 * -------------------------------------- + scale factor
962 * M = blank_scale * gradient
965 static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
967 u32 c_val, m_val, duty_cycle, hblank;
969 c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 +
970 H_SCALEFACTOR) * 1000;
971 m_val = (H_BLANKSCALE * H_GRADIENT)/256;
972 m_val = (m_val * 1000000)/hfreq;
973 duty_cycle = c_val - m_val;
974 hblank = (xres * duty_cycle)/(100000 - duty_cycle);
979 * fb_get_hblank_by_dclk - get horizontal blank time given pixelclock
980 * @dclk: pixelclock in Hz
981 * @xres: horizontal resolution in pixels
986 * hblank = ------------------
989 * duty cycle = percent of htotal assigned to inactive display
990 * duty cycle = C - (M * h_period)
992 * where: h_period = SQRT(100 - C + (0.4 * xres * M)/dclk) + C - 100
993 * -----------------------------------------------
999 static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)
1001 u32 duty_cycle, h_period, hblank;
1004 h_period = 100 - C_VAL;
1005 h_period *= h_period;
1006 h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);
1009 h_period = int_sqrt(h_period);
1010 h_period -= (100 - C_VAL) * 100;
1012 h_period /= 2 * M_VAL;
1014 duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;
1015 hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;
1021 * fb_get_hfreq - estimate hsync
1022 * @vfreq: vertical refresh rate
1023 * @yres: vertical resolution
1027 * (yres + front_port) * vfreq * 1000000
1028 * hfreq = -------------------------------------
1029 * (1000000 - (vfreq * FLYBACK)
1033 static u32 fb_get_hfreq(u32 vfreq, u32 yres)
1037 divisor = (1000000 - (vfreq * FLYBACK))/1000;
1038 hfreq = (yres + V_FRONTPORCH) * vfreq * 1000;
1039 return (hfreq/divisor);
1042 static void fb_timings_vfreq(struct __fb_timings *timings)
1044 timings->hfreq = fb_get_hfreq(timings->vfreq, timings->vactive);
1045 timings->vblank = fb_get_vblank(timings->hfreq);
1046 timings->vtotal = timings->vactive + timings->vblank;
1047 timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1049 timings->htotal = timings->hactive + timings->hblank;
1050 timings->dclk = timings->htotal * timings->hfreq;
1053 static void fb_timings_hfreq(struct __fb_timings *timings)
1055 timings->vblank = fb_get_vblank(timings->hfreq);
1056 timings->vtotal = timings->vactive + timings->vblank;
1057 timings->vfreq = timings->hfreq/timings->vtotal;
1058 timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1060 timings->htotal = timings->hactive + timings->hblank;
1061 timings->dclk = timings->htotal * timings->hfreq;
1064 static void fb_timings_dclk(struct __fb_timings *timings)
1066 timings->hblank = fb_get_hblank_by_dclk(timings->dclk,
1068 timings->htotal = timings->hactive + timings->hblank;
1069 timings->hfreq = timings->dclk/timings->htotal;
1070 timings->vblank = fb_get_vblank(timings->hfreq);
1071 timings->vtotal = timings->vactive + timings->vblank;
1072 timings->vfreq = timings->hfreq/timings->vtotal;
1076 * fb_get_mode - calculates video mode using VESA GTF
1077 * @flags: if: 0 - maximize vertical refresh rate
1078 * 1 - vrefresh-driven calculation;
1079 * 2 - hscan-driven calculation;
1080 * 3 - pixelclock-driven calculation;
1081 * @val: depending on @flags, ignored, vrefresh, hsync or pixelclock
1082 * @var: pointer to fb_var_screeninfo
1083 * @info: pointer to fb_info
1086 * Calculates video mode based on monitor specs using VESA GTF.
1087 * The GTF is best for VESA GTF compliant monitors but is
1088 * specifically formulated to work for older monitors as well.
1090 * If @flag==0, the function will attempt to maximize the
1091 * refresh rate. Otherwise, it will calculate timings based on
1092 * the flag and accompanying value.
1094 * If FB_IGNOREMON bit is set in @flags, monitor specs will be
1095 * ignored and @var will be filled with the calculated timings.
1097 * All calculations are based on the VESA GTF Spreadsheet
1098 * available at VESA's public ftp (http://www.vesa.org).
1101 * The timings generated by the GTF will be different from VESA
1102 * DMT. It might be a good idea to keep a table of standard
1103 * VESA modes as well. The GTF may also not work for some displays,
1104 * such as, and especially, analog TV.
1107 * A valid info->monspecs, otherwise 'safe numbers' will be used.
1109 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)
1111 struct __fb_timings *timings;
1112 u32 interlace = 1, dscan = 1;
1113 u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;
1116 timings = kzalloc(sizeof(struct __fb_timings), GFP_KERNEL);
1122 * If monspecs are invalid, use values that are enough
1125 if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||
1126 !info->monspecs.dclkmax ||
1127 info->monspecs.hfmax < info->monspecs.hfmin ||
1128 info->monspecs.vfmax < info->monspecs.vfmin ||
1129 info->monspecs.dclkmax < info->monspecs.dclkmin) {
1130 hfmin = 29000; hfmax = 30000;
1131 vfmin = 60; vfmax = 60;
1132 dclkmin = 0; dclkmax = 25000000;
1134 hfmin = info->monspecs.hfmin;
1135 hfmax = info->monspecs.hfmax;
1136 vfmin = info->monspecs.vfmin;
1137 vfmax = info->monspecs.vfmax;
1138 dclkmin = info->monspecs.dclkmin;
1139 dclkmax = info->monspecs.dclkmax;
1142 timings->hactive = var->xres;
1143 timings->vactive = var->yres;
1144 if (var->vmode & FB_VMODE_INTERLACED) {
1145 timings->vactive /= 2;
1148 if (var->vmode & FB_VMODE_DOUBLE) {
1149 timings->vactive *= 2;
1153 switch (flags & ~FB_IGNOREMON) {
1154 case FB_MAXTIMINGS: /* maximize refresh rate */
1155 timings->hfreq = hfmax;
1156 fb_timings_hfreq(timings);
1157 if (timings->vfreq > vfmax) {
1158 timings->vfreq = vfmax;
1159 fb_timings_vfreq(timings);
1161 if (timings->dclk > dclkmax) {
1162 timings->dclk = dclkmax;
1163 fb_timings_dclk(timings);
1166 case FB_VSYNCTIMINGS: /* vrefresh driven */
1167 timings->vfreq = val;
1168 fb_timings_vfreq(timings);
1170 case FB_HSYNCTIMINGS: /* hsync driven */
1171 timings->hfreq = val;
1172 fb_timings_hfreq(timings);
1174 case FB_DCLKTIMINGS: /* pixelclock driven */
1175 timings->dclk = PICOS2KHZ(val) * 1000;
1176 fb_timings_dclk(timings);
1183 if (err || (!(flags & FB_IGNOREMON) &&
1184 (timings->vfreq < vfmin || timings->vfreq > vfmax ||
1185 timings->hfreq < hfmin || timings->hfreq > hfmax ||
1186 timings->dclk < dclkmin || timings->dclk > dclkmax))) {
1189 var->pixclock = KHZ2PICOS(timings->dclk/1000);
1190 var->hsync_len = (timings->htotal * 8)/100;
1191 var->right_margin = (timings->hblank/2) - var->hsync_len;
1192 var->left_margin = timings->hblank - var->right_margin -
1194 var->vsync_len = (3 * interlace)/dscan;
1195 var->lower_margin = (1 * interlace)/dscan;
1196 var->upper_margin = (timings->vblank * interlace)/dscan -
1197 (var->vsync_len + var->lower_margin);
1204 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
1208 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1212 void fb_destroy_modedb(struct fb_videomode *modedb)
1215 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
1216 struct fb_info *info)
1220 #endif /* CONFIG_FB_MODE_HELPERS */
1223 * fb_validate_mode - validates var against monitor capabilities
1224 * @var: pointer to fb_var_screeninfo
1225 * @info: pointer to fb_info
1228 * Validates video mode against monitor capabilities specified in
1232 * A valid info->monspecs.
1234 int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
1236 u32 hfreq, vfreq, htotal, vtotal, pixclock;
1237 u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
1240 * If monspecs are invalid, use values that are enough
1243 if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
1244 !info->monspecs.dclkmax ||
1245 info->monspecs.hfmax < info->monspecs.hfmin ||
1246 info->monspecs.vfmax < info->monspecs.vfmin ||
1247 info->monspecs.dclkmax < info->monspecs.dclkmin) {
1248 hfmin = 29000; hfmax = 30000;
1249 vfmin = 60; vfmax = 60;
1250 dclkmin = 0; dclkmax = 25000000;
1252 hfmin = info->monspecs.hfmin;
1253 hfmax = info->monspecs.hfmax;
1254 vfmin = info->monspecs.vfmin;
1255 vfmax = info->monspecs.vfmax;
1256 dclkmin = info->monspecs.dclkmin;
1257 dclkmax = info->monspecs.dclkmax;
1262 pixclock = PICOS2KHZ(var->pixclock) * 1000;
1264 htotal = var->xres + var->right_margin + var->hsync_len +
1266 vtotal = var->yres + var->lower_margin + var->vsync_len +
1269 if (var->vmode & FB_VMODE_INTERLACED)
1271 if (var->vmode & FB_VMODE_DOUBLE)
1274 hfreq = pixclock/htotal;
1275 hfreq = (hfreq + 500) / 1000 * 1000;
1277 vfreq = hfreq/vtotal;
1279 return (vfreq < vfmin || vfreq > vfmax ||
1280 hfreq < hfmin || hfreq > hfmax ||
1281 pixclock < dclkmin || pixclock > dclkmax) ?
1285 #if defined(__i386__)
1286 #include <linux/pci.h>
1289 * We need to ensure that the EDID block is only returned for
1290 * the primary graphics adapter.
1293 const unsigned char *fb_firmware_edid(struct device *device)
1295 struct pci_dev *dev = NULL;
1296 struct resource *res = NULL;
1297 unsigned char *edid = NULL;
1300 dev = to_pci_dev(device);
1303 res = &dev->resource[PCI_ROM_RESOURCE];
1305 if (res && res->flags & IORESOURCE_ROM_SHADOW)
1306 edid = edid_info.dummy;
1311 const unsigned char *fb_firmware_edid(struct device *device)
1317 EXPORT_SYMBOL(fb_parse_edid);
1318 EXPORT_SYMBOL(fb_edid_to_monspecs);
1319 EXPORT_SYMBOL(fb_firmware_edid);
1320 EXPORT_SYMBOL(fb_get_mode);
1321 EXPORT_SYMBOL(fb_validate_mode);
1322 EXPORT_SYMBOL(fb_destroy_modedb);