Merge tag 'perf-urgent-for-mingo-4.14-20170928' of git://git.kernel.org/pub/scm/linux...
[sfrench/cifs-2.6.git] / drivers / video / fbdev / core / fbmon.c
1 /*
2  * linux/drivers/video/fbmon.c
3  *
4  * Copyright (C) 2002 James Simmons <jsimmons@users.sf.net>
5  *
6  * Credits:
7  *
8  * The EDID Parser is a conglomeration from the following sources:
9  *
10  *   1. SciTech SNAP Graphics Architecture
11  *      Copyright (C) 1991-2002 SciTech Software, Inc. All rights reserved.
12  *
13  *   2. XFree86 4.3.0, interpret_edid.c
14  *      Copyright 1998 by Egbert Eich <Egbert.Eich@Physik.TU-Darmstadt.DE>
15  *
16  *   3. John Fremlin <vii@users.sourceforge.net> and
17  *      Ani Joshi <ajoshi@unixbox.com>
18  *
19  * Generalized Timing Formula is derived from:
20  *
21  *      GTF Spreadsheet by Andy Morrish (1/5/97)
22  *      available at http://www.vesa.org
23  *
24  * This file is subject to the terms and conditions of the GNU General Public
25  * License.  See the file COPYING in the main directory of this archive
26  * for more details.
27  *
28  */
29 #include <linux/fb.h>
30 #include <linux/module.h>
31 #include <linux/pci.h>
32 #include <linux/slab.h>
33 #include <video/edid.h>
34 #include <video/of_videomode.h>
35 #include <video/videomode.h>
36 #include "../edid.h"
37
38 /*
39  * EDID parser
40  */
41
42 #undef DEBUG  /* define this for verbose EDID parsing output */
43
44 #ifdef DEBUG
45 #define DPRINTK(fmt, args...) printk(fmt,## args)
46 #else
47 #define DPRINTK(fmt, args...)
48 #endif
49
50 #define FBMON_FIX_HEADER  1
51 #define FBMON_FIX_INPUT   2
52 #define FBMON_FIX_TIMINGS 3
53
54 #ifdef CONFIG_FB_MODE_HELPERS
55 struct broken_edid {
56         u8  manufacturer[4];
57         u32 model;
58         u32 fix;
59 };
60
61 static 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
82 static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
83         0xff, 0xff, 0xff, 0x00
84 };
85
86 static 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
96 static 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         else
103                 return 0;
104 }
105
106 static 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         else
113                 return 0;
114 }
115
116 static 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         else
123                 return 0;
124 }
125
126 static 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         else
133                 return 0;
134 }
135
136 static 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         else
142                 return 0;
143 }
144
145 static 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 will
179                    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
207 static 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
256 static 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
277 static 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
292 static 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
310 static 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
326 static 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
381 static 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
409 static 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
494 static 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                         else
525                                 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->dclkmax
545             && PICOS2KHZ(mode->pixclock) * 1000 > specs->dclkmax) {
546                 DPRINTK("        mode exceed max DCLK\n");
547                 return 0;
548         }
549
550         return 1;
551 }
552
553 static 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
564 static 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 database
606  * @edid: EDID data
607  * @dbsize: database size
608  *
609  * RETURNS: struct fb_videomode, @dbsize contains length of database
610  *
611  * DESCRIPTION:
612  * This function builds a mode database using the contents of the EDID
613  * data
614  */
615 static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize,
616                                              const struct fb_monspecs *specs)
617 {
618         struct fb_videomode *mode, *m;
619         unsigned char *block;
620         int num = 0, i, first = 1;
621         int ver, rev;
622
623         mode = kzalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
624         if (mode == NULL)
625                 return NULL;
626
627         if (edid == NULL || !edid_checksum(edid) ||
628             !edid_check_header(edid)) {
629                 kfree(mode);
630                 return NULL;
631         }
632
633         ver = edid[EDID_STRUCT_VERSION];
634         rev = edid[EDID_STRUCT_REVISION];
635
636         *dbsize = 0;
637
638         DPRINTK("   Detailed Timings\n");
639         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
640         for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
641                 if (!(block[0] == 0x00 && block[1] == 0x00)) {
642                         get_detailed_timing(block, &mode[num]);
643                         if (first) {
644                                 mode[num].flag |= FB_MODE_IS_FIRST;
645                                 first = 0;
646                         }
647                         num++;
648                 }
649         }
650
651         DPRINTK("   Supported VESA Modes\n");
652         block = edid + ESTABLISHED_TIMING_1;
653         num += get_est_timing(block, &mode[num]);
654
655         DPRINTK("   Standard Timings\n");
656         block = edid + STD_TIMING_DESCRIPTIONS_START;
657         for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE)
658                 num += get_std_timing(block, &mode[num], ver, rev, specs);
659
660         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
661         for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
662                 if (block[0] == 0x00 && block[1] == 0x00 && block[3] == 0xfa)
663                         num += get_dst_timing(block + 5, &mode[num],
664                                               ver, rev, specs);
665         }
666
667         /* Yikes, EDID data is totally useless */
668         if (!num) {
669                 kfree(mode);
670                 return NULL;
671         }
672
673         *dbsize = num;
674         m = kmalloc(num * sizeof(struct fb_videomode), GFP_KERNEL);
675         if (!m)
676                 return mode;
677         memmove(m, mode, num * sizeof(struct fb_videomode));
678         kfree(mode);
679         return m;
680 }
681
682 /**
683  * fb_destroy_modedb - destroys mode database
684  * @modedb: mode database to destroy
685  *
686  * DESCRIPTION:
687  * Destroy mode database created by fb_create_modedb
688  */
689 void fb_destroy_modedb(struct fb_videomode *modedb)
690 {
691         kfree(modedb);
692 }
693
694 static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
695 {
696         int i, retval = 1;
697         unsigned char *block;
698
699         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
700
701         DPRINTK("      Monitor Operating Limits: ");
702
703         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
704                 if (edid_is_limits_block(block)) {
705                         specs->hfmin = H_MIN_RATE * 1000;
706                         specs->hfmax = H_MAX_RATE * 1000;
707                         specs->vfmin = V_MIN_RATE;
708                         specs->vfmax = V_MAX_RATE;
709                         specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;
710                         specs->gtf = (GTF_SUPPORT) ? 1 : 0;
711                         retval = 0;
712                         DPRINTK("From EDID\n");
713                         break;
714                 }
715         }
716
717         /* estimate monitor limits based on modes supported */
718         if (retval) {
719                 struct fb_videomode *modes, *mode;
720                 int num_modes, hz, hscan, pixclock;
721                 int vtotal, htotal;
722
723                 modes = fb_create_modedb(edid, &num_modes, specs);
724                 if (!modes) {
725                         DPRINTK("None Available\n");
726                         return 1;
727                 }
728
729                 retval = 0;
730                 for (i = 0; i < num_modes; i++) {
731                         mode = &modes[i];
732                         pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
733                         htotal = mode->xres + mode->right_margin + mode->hsync_len
734                                 + mode->left_margin;
735                         vtotal = mode->yres + mode->lower_margin + mode->vsync_len
736                                 + mode->upper_margin;
737
738                         if (mode->vmode & FB_VMODE_INTERLACED)
739                                 vtotal /= 2;
740
741                         if (mode->vmode & FB_VMODE_DOUBLE)
742                                 vtotal *= 2;
743
744                         hscan = (pixclock + htotal / 2) / htotal;
745                         hscan = (hscan + 500) / 1000 * 1000;
746                         hz = (hscan + vtotal / 2) / vtotal;
747
748                         if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
749                                 specs->dclkmax = pixclock;
750
751                         if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
752                                 specs->dclkmin = pixclock;
753
754                         if (specs->hfmax == 0 || specs->hfmax < hscan)
755                                 specs->hfmax = hscan;
756
757                         if (specs->hfmin == 0 || specs->hfmin > hscan)
758                                 specs->hfmin = hscan;
759
760                         if (specs->vfmax == 0 || specs->vfmax < hz)
761                                 specs->vfmax = hz;
762
763                         if (specs->vfmin == 0 || specs->vfmin > hz)
764                                 specs->vfmin = hz;
765                 }
766                 DPRINTK("Extrapolated\n");
767                 fb_destroy_modedb(modes);
768         }
769         DPRINTK("           H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",
770                 specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,
771                 specs->vfmax, specs->dclkmax/1000000);
772         return retval;
773 }
774
775 static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
776 {
777         unsigned char c, *block;
778
779         block = edid + EDID_STRUCT_DISPLAY;
780
781         fb_get_monitor_limits(edid, specs);
782
783         c = block[0] & 0x80;
784         specs->input = 0;
785         if (c) {
786                 specs->input |= FB_DISP_DDI;
787                 DPRINTK("      Digital Display Input");
788         } else {
789                 DPRINTK("      Analog Display Input: Input Voltage - ");
790                 switch ((block[0] & 0x60) >> 5) {
791                 case 0:
792                         DPRINTK("0.700V/0.300V");
793                         specs->input |= FB_DISP_ANA_700_300;
794                         break;
795                 case 1:
796                         DPRINTK("0.714V/0.286V");
797                         specs->input |= FB_DISP_ANA_714_286;
798                         break;
799                 case 2:
800                         DPRINTK("1.000V/0.400V");
801                         specs->input |= FB_DISP_ANA_1000_400;
802                         break;
803                 case 3:
804                         DPRINTK("0.700V/0.000V");
805                         specs->input |= FB_DISP_ANA_700_000;
806                         break;
807                 }
808         }
809         DPRINTK("\n      Sync: ");
810         c = block[0] & 0x10;
811         if (c)
812                 DPRINTK("      Configurable signal level\n");
813         c = block[0] & 0x0f;
814         specs->signal = 0;
815         if (c & 0x10) {
816                 DPRINTK("Blank to Blank ");
817                 specs->signal |= FB_SIGNAL_BLANK_BLANK;
818         }
819         if (c & 0x08) {
820                 DPRINTK("Separate ");
821                 specs->signal |= FB_SIGNAL_SEPARATE;
822         }
823         if (c & 0x04) {
824                 DPRINTK("Composite ");
825                 specs->signal |= FB_SIGNAL_COMPOSITE;
826         }
827         if (c & 0x02) {
828                 DPRINTK("Sync on Green ");
829                 specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
830         }
831         if (c & 0x01) {
832                 DPRINTK("Serration on ");
833                 specs->signal |= FB_SIGNAL_SERRATION_ON;
834         }
835         DPRINTK("\n");
836         specs->max_x = block[1];
837         specs->max_y = block[2];
838         DPRINTK("      Max H-size in cm: ");
839         if (specs->max_x)
840                 DPRINTK("%d\n", specs->max_x);
841         else
842                 DPRINTK("variable\n");
843         DPRINTK("      Max V-size in cm: ");
844         if (specs->max_y)
845                 DPRINTK("%d\n", specs->max_y);
846         else
847                 DPRINTK("variable\n");
848
849         c = block[3];
850         specs->gamma = c+100;
851         DPRINTK("      Gamma: ");
852         DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
853
854         get_dpms_capabilities(block[4], specs);
855
856         switch ((block[4] & 0x18) >> 3) {
857         case 0:
858                 DPRINTK("      Monochrome/Grayscale\n");
859                 specs->input |= FB_DISP_MONO;
860                 break;
861         case 1:
862                 DPRINTK("      RGB Color Display\n");
863                 specs->input |= FB_DISP_RGB;
864                 break;
865         case 2:
866                 DPRINTK("      Non-RGB Multicolor Display\n");
867                 specs->input |= FB_DISP_MULTI;
868                 break;
869         default:
870                 DPRINTK("      Unknown\n");
871                 specs->input |= FB_DISP_UNKNOWN;
872                 break;
873         }
874
875         get_chroma(block, specs);
876
877         specs->misc = 0;
878         c = block[4] & 0x7;
879         if (c & 0x04) {
880                 DPRINTK("      Default color format is primary\n");
881                 specs->misc |= FB_MISC_PRIM_COLOR;
882         }
883         if (c & 0x02) {
884                 DPRINTK("      First DETAILED Timing is preferred\n");
885                 specs->misc |= FB_MISC_1ST_DETAIL;
886         }
887         if (c & 0x01) {
888                 printk("      Display is GTF capable\n");
889                 specs->gtf = 1;
890         }
891 }
892
893 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
894 {
895         int i;
896         unsigned char *block;
897
898         if (edid == NULL || var == NULL)
899                 return 1;
900
901         if (!(edid_checksum(edid)))
902                 return 1;
903
904         if (!(edid_check_header(edid)))
905                 return 1;
906
907         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
908
909         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
910                 if (edid_is_timing_block(block)) {
911                         var->xres = var->xres_virtual = H_ACTIVE;
912                         var->yres = var->yres_virtual = V_ACTIVE;
913                         var->height = var->width = 0;
914                         var->right_margin = H_SYNC_OFFSET;
915                         var->left_margin = (H_ACTIVE + H_BLANKING) -
916                                 (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
917                         var->upper_margin = V_BLANKING - V_SYNC_OFFSET -
918                                 V_SYNC_WIDTH;
919                         var->lower_margin = V_SYNC_OFFSET;
920                         var->hsync_len = H_SYNC_WIDTH;
921                         var->vsync_len = V_SYNC_WIDTH;
922                         var->pixclock = PIXEL_CLOCK;
923                         var->pixclock /= 1000;
924                         var->pixclock = KHZ2PICOS(var->pixclock);
925
926                         if (HSYNC_POSITIVE)
927                                 var->sync |= FB_SYNC_HOR_HIGH_ACT;
928                         if (VSYNC_POSITIVE)
929                                 var->sync |= FB_SYNC_VERT_HIGH_ACT;
930                         return 0;
931                 }
932         }
933         return 1;
934 }
935
936 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
937 {
938         unsigned char *block;
939         int i, found = 0;
940
941         if (edid == NULL)
942                 return;
943
944         if (!(edid_checksum(edid)))
945                 return;
946
947         if (!(edid_check_header(edid)))
948                 return;
949
950         memset(specs, 0, sizeof(struct fb_monspecs));
951
952         specs->version = edid[EDID_STRUCT_VERSION];
953         specs->revision = edid[EDID_STRUCT_REVISION];
954
955         DPRINTK("========================================\n");
956         DPRINTK("Display Information (EDID)\n");
957         DPRINTK("========================================\n");
958         DPRINTK("   EDID Version %d.%d\n", (int) specs->version,
959                (int) specs->revision);
960
961         parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);
962
963         block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
964         for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
965                 if (edid_is_serial_block(block)) {
966                         copy_string(block, specs->serial_no);
967                         DPRINTK("   Serial Number: %s\n", specs->serial_no);
968                 } else if (edid_is_ascii_block(block)) {
969                         copy_string(block, specs->ascii);
970                         DPRINTK("   ASCII Block: %s\n", specs->ascii);
971                 } else if (edid_is_monitor_block(block)) {
972                         copy_string(block, specs->monitor);
973                         DPRINTK("   Monitor Name: %s\n", specs->monitor);
974                 }
975         }
976
977         DPRINTK("   Display Characteristics:\n");
978         get_monspecs(edid, specs);
979
980         specs->modedb = fb_create_modedb(edid, &specs->modedb_len, specs);
981
982         /*
983          * Workaround for buggy EDIDs that sets that the first
984          * detailed timing is preferred but has not detailed
985          * timing specified
986          */
987         for (i = 0; i < specs->modedb_len; i++) {
988                 if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {
989                         found = 1;
990                         break;
991                 }
992         }
993
994         if (!found)
995                 specs->misc &= ~FB_MISC_1ST_DETAIL;
996
997         DPRINTK("========================================\n");
998 }
999
1000 /**
1001  * fb_edid_add_monspecs() - add monitor video modes from E-EDID data
1002  * @edid:       128 byte array with an E-EDID block
1003  * @spacs:      monitor specs to be extended
1004  */
1005 void fb_edid_add_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1006 {
1007         unsigned char *block;
1008         struct fb_videomode *m;
1009         int num = 0, i;
1010         u8 svd[64], edt[(128 - 4) / DETAILED_TIMING_DESCRIPTION_SIZE];
1011         u8 pos = 4, svd_n = 0;
1012
1013         if (!edid)
1014                 return;
1015
1016         if (!edid_checksum(edid))
1017                 return;
1018
1019         if (edid[0] != 0x2 ||
1020             edid[2] < 4 || edid[2] > 128 - DETAILED_TIMING_DESCRIPTION_SIZE)
1021                 return;
1022
1023         DPRINTK("  Short Video Descriptors\n");
1024
1025         while (pos < edid[2]) {
1026                 u8 len = edid[pos] & 0x1f, type = (edid[pos] >> 5) & 7;
1027                 pr_debug("Data block %u of %u bytes\n", type, len);
1028                 if (type == 2) {
1029                         for (i = pos; i < pos + len; i++) {
1030                                 u8 idx = edid[pos + i] & 0x7f;
1031                                 svd[svd_n++] = idx;
1032                                 pr_debug("N%sative mode #%d\n",
1033                                          edid[pos + i] & 0x80 ? "" : "on-n", idx);
1034                         }
1035                 } else if (type == 3 && len >= 3) {
1036                         /* Check Vendor Specific Data Block.  For HDMI,
1037                            it is always 00-0C-03 for HDMI Licensing, LLC. */
1038                         if (edid[pos + 1] == 3 && edid[pos + 2] == 0xc &&
1039                             edid[pos + 3] == 0)
1040                                 specs->misc |= FB_MISC_HDMI;
1041                 }
1042                 pos += len + 1;
1043         }
1044
1045         block = edid + edid[2];
1046
1047         DPRINTK("  Extended Detailed Timings\n");
1048
1049         for (i = 0; i < (128 - edid[2]) / DETAILED_TIMING_DESCRIPTION_SIZE;
1050              i++, block += DETAILED_TIMING_DESCRIPTION_SIZE)
1051                 if (PIXEL_CLOCK != 0)
1052                         edt[num++] = block - edid;
1053
1054         /* Yikes, EDID data is totally useless */
1055         if (!(num + svd_n))
1056                 return;
1057
1058         m = kzalloc((specs->modedb_len + num + svd_n) *
1059                        sizeof(struct fb_videomode), GFP_KERNEL);
1060
1061         if (!m)
1062                 return;
1063
1064         memcpy(m, specs->modedb, specs->modedb_len * sizeof(struct fb_videomode));
1065
1066         for (i = specs->modedb_len; i < specs->modedb_len + num; i++) {
1067                 get_detailed_timing(edid + edt[i - specs->modedb_len], &m[i]);
1068                 if (i == specs->modedb_len)
1069                         m[i].flag |= FB_MODE_IS_FIRST;
1070                 pr_debug("Adding %ux%u@%u\n", m[i].xres, m[i].yres, m[i].refresh);
1071         }
1072
1073         for (i = specs->modedb_len + num; i < specs->modedb_len + num + svd_n; i++) {
1074                 int idx = svd[i - specs->modedb_len - num];
1075                 if (!idx || idx >= ARRAY_SIZE(cea_modes)) {
1076                         pr_warn("Reserved SVD code %d\n", idx);
1077                 } else if (!cea_modes[idx].xres) {
1078                         pr_warn("Unimplemented SVD code %d\n", idx);
1079                 } else {
1080                         memcpy(&m[i], cea_modes + idx, sizeof(m[i]));
1081                         pr_debug("Adding SVD #%d: %ux%u@%u\n", idx,
1082                                  m[i].xres, m[i].yres, m[i].refresh);
1083                 }
1084         }
1085
1086         kfree(specs->modedb);
1087         specs->modedb = m;
1088         specs->modedb_len = specs->modedb_len + num + svd_n;
1089 }
1090
1091 /*
1092  * VESA Generalized Timing Formula (GTF)
1093  */
1094
1095 #define FLYBACK                     550
1096 #define V_FRONTPORCH                1
1097 #define H_OFFSET                    40
1098 #define H_SCALEFACTOR               20
1099 #define H_BLANKSCALE                128
1100 #define H_GRADIENT                  600
1101 #define C_VAL                       30
1102 #define M_VAL                       300
1103
1104 struct __fb_timings {
1105         u32 dclk;
1106         u32 hfreq;
1107         u32 vfreq;
1108         u32 hactive;
1109         u32 vactive;
1110         u32 hblank;
1111         u32 vblank;
1112         u32 htotal;
1113         u32 vtotal;
1114 };
1115
1116 /**
1117  * fb_get_vblank - get vertical blank time
1118  * @hfreq: horizontal freq
1119  *
1120  * DESCRIPTION:
1121  * vblank = right_margin + vsync_len + left_margin
1122  *
1123  *    given: right_margin = 1 (V_FRONTPORCH)
1124  *           vsync_len    = 3
1125  *           flyback      = 550
1126  *
1127  *                          flyback * hfreq
1128  *           left_margin  = --------------- - vsync_len
1129  *                           1000000
1130  */
1131 static u32 fb_get_vblank(u32 hfreq)
1132 {
1133         u32 vblank;
1134
1135         vblank = (hfreq * FLYBACK)/1000;
1136         vblank = (vblank + 500)/1000;
1137         return (vblank + V_FRONTPORCH);
1138 }
1139
1140 /**
1141  * fb_get_hblank_by_freq - get horizontal blank time given hfreq
1142  * @hfreq: horizontal freq
1143  * @xres: horizontal resolution in pixels
1144  *
1145  * DESCRIPTION:
1146  *
1147  *           xres * duty_cycle
1148  * hblank = ------------------
1149  *           100 - duty_cycle
1150  *
1151  * duty cycle = percent of htotal assigned to inactive display
1152  * duty cycle = C - (M/Hfreq)
1153  *
1154  * where: C = ((offset - scale factor) * blank_scale)
1155  *            -------------------------------------- + scale factor
1156  *                        256
1157  *        M = blank_scale * gradient
1158  *
1159  */
1160 static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
1161 {
1162         u32 c_val, m_val, duty_cycle, hblank;
1163
1164         c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 +
1165                  H_SCALEFACTOR) * 1000;
1166         m_val = (H_BLANKSCALE * H_GRADIENT)/256;
1167         m_val = (m_val * 1000000)/hfreq;
1168         duty_cycle = c_val - m_val;
1169         hblank = (xres * duty_cycle)/(100000 - duty_cycle);
1170         return (hblank);
1171 }
1172
1173 /**
1174  * fb_get_hblank_by_dclk - get horizontal blank time given pixelclock
1175  * @dclk: pixelclock in Hz
1176  * @xres: horizontal resolution in pixels
1177  *
1178  * DESCRIPTION:
1179  *
1180  *           xres * duty_cycle
1181  * hblank = ------------------
1182  *           100 - duty_cycle
1183  *
1184  * duty cycle = percent of htotal assigned to inactive display
1185  * duty cycle = C - (M * h_period)
1186  *
1187  * where: h_period = SQRT(100 - C + (0.4 * xres * M)/dclk) + C - 100
1188  *                   -----------------------------------------------
1189  *                                    2 * M
1190  *        M = 300;
1191  *        C = 30;
1192
1193  */
1194 static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)
1195 {
1196         u32 duty_cycle, h_period, hblank;
1197
1198         dclk /= 1000;
1199         h_period = 100 - C_VAL;
1200         h_period *= h_period;
1201         h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);
1202         h_period *= 10000;
1203
1204         h_period = int_sqrt(h_period);
1205         h_period -= (100 - C_VAL) * 100;
1206         h_period *= 1000;
1207         h_period /= 2 * M_VAL;
1208
1209         duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;
1210         hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;
1211         hblank &= ~15;
1212         return (hblank);
1213 }
1214
1215 /**
1216  * fb_get_hfreq - estimate hsync
1217  * @vfreq: vertical refresh rate
1218  * @yres: vertical resolution
1219  *
1220  * DESCRIPTION:
1221  *
1222  *          (yres + front_port) * vfreq * 1000000
1223  * hfreq = -------------------------------------
1224  *          (1000000 - (vfreq * FLYBACK)
1225  *
1226  */
1227
1228 static u32 fb_get_hfreq(u32 vfreq, u32 yres)
1229 {
1230         u32 divisor, hfreq;
1231
1232         divisor = (1000000 - (vfreq * FLYBACK))/1000;
1233         hfreq = (yres + V_FRONTPORCH) * vfreq  * 1000;
1234         return (hfreq/divisor);
1235 }
1236
1237 static void fb_timings_vfreq(struct __fb_timings *timings)
1238 {
1239         timings->hfreq = fb_get_hfreq(timings->vfreq, timings->vactive);
1240         timings->vblank = fb_get_vblank(timings->hfreq);
1241         timings->vtotal = timings->vactive + timings->vblank;
1242         timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1243                                                  timings->hactive);
1244         timings->htotal = timings->hactive + timings->hblank;
1245         timings->dclk = timings->htotal * timings->hfreq;
1246 }
1247
1248 static void fb_timings_hfreq(struct __fb_timings *timings)
1249 {
1250         timings->vblank = fb_get_vblank(timings->hfreq);
1251         timings->vtotal = timings->vactive + timings->vblank;
1252         timings->vfreq = timings->hfreq/timings->vtotal;
1253         timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1254                                                  timings->hactive);
1255         timings->htotal = timings->hactive + timings->hblank;
1256         timings->dclk = timings->htotal * timings->hfreq;
1257 }
1258
1259 static void fb_timings_dclk(struct __fb_timings *timings)
1260 {
1261         timings->hblank = fb_get_hblank_by_dclk(timings->dclk,
1262                                                 timings->hactive);
1263         timings->htotal = timings->hactive + timings->hblank;
1264         timings->hfreq = timings->dclk/timings->htotal;
1265         timings->vblank = fb_get_vblank(timings->hfreq);
1266         timings->vtotal = timings->vactive + timings->vblank;
1267         timings->vfreq = timings->hfreq/timings->vtotal;
1268 }
1269
1270 /*
1271  * fb_get_mode - calculates video mode using VESA GTF
1272  * @flags: if: 0 - maximize vertical refresh rate
1273  *             1 - vrefresh-driven calculation;
1274  *             2 - hscan-driven calculation;
1275  *             3 - pixelclock-driven calculation;
1276  * @val: depending on @flags, ignored, vrefresh, hsync or pixelclock
1277  * @var: pointer to fb_var_screeninfo
1278  * @info: pointer to fb_info
1279  *
1280  * DESCRIPTION:
1281  * Calculates video mode based on monitor specs using VESA GTF.
1282  * The GTF is best for VESA GTF compliant monitors but is
1283  * specifically formulated to work for older monitors as well.
1284  *
1285  * If @flag==0, the function will attempt to maximize the
1286  * refresh rate.  Otherwise, it will calculate timings based on
1287  * the flag and accompanying value.
1288  *
1289  * If FB_IGNOREMON bit is set in @flags, monitor specs will be
1290  * ignored and @var will be filled with the calculated timings.
1291  *
1292  * All calculations are based on the VESA GTF Spreadsheet
1293  * available at VESA's public ftp (http://www.vesa.org).
1294  *
1295  * NOTES:
1296  * The timings generated by the GTF will be different from VESA
1297  * DMT.  It might be a good idea to keep a table of standard
1298  * VESA modes as well.  The GTF may also not work for some displays,
1299  * such as, and especially, analog TV.
1300  *
1301  * REQUIRES:
1302  * A valid info->monspecs, otherwise 'safe numbers' will be used.
1303  */
1304 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)
1305 {
1306         struct __fb_timings *timings;
1307         u32 interlace = 1, dscan = 1;
1308         u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;
1309
1310
1311         timings = kzalloc(sizeof(struct __fb_timings), GFP_KERNEL);
1312
1313         if (!timings)
1314                 return -ENOMEM;
1315
1316         /*
1317          * If monspecs are invalid, use values that are enough
1318          * for 640x480@60
1319          */
1320         if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||
1321             !info->monspecs.dclkmax ||
1322             info->monspecs.hfmax < info->monspecs.hfmin ||
1323             info->monspecs.vfmax < info->monspecs.vfmin ||
1324             info->monspecs.dclkmax < info->monspecs.dclkmin) {
1325                 hfmin = 29000; hfmax = 30000;
1326                 vfmin = 60; vfmax = 60;
1327                 dclkmin = 0; dclkmax = 25000000;
1328         } else {
1329                 hfmin = info->monspecs.hfmin;
1330                 hfmax = info->monspecs.hfmax;
1331                 vfmin = info->monspecs.vfmin;
1332                 vfmax = info->monspecs.vfmax;
1333                 dclkmin = info->monspecs.dclkmin;
1334                 dclkmax = info->monspecs.dclkmax;
1335         }
1336
1337         timings->hactive = var->xres;
1338         timings->vactive = var->yres;
1339         if (var->vmode & FB_VMODE_INTERLACED) {
1340                 timings->vactive /= 2;
1341                 interlace = 2;
1342         }
1343         if (var->vmode & FB_VMODE_DOUBLE) {
1344                 timings->vactive *= 2;
1345                 dscan = 2;
1346         }
1347
1348         switch (flags & ~FB_IGNOREMON) {
1349         case FB_MAXTIMINGS: /* maximize refresh rate */
1350                 timings->hfreq = hfmax;
1351                 fb_timings_hfreq(timings);
1352                 if (timings->vfreq > vfmax) {
1353                         timings->vfreq = vfmax;
1354                         fb_timings_vfreq(timings);
1355                 }
1356                 if (timings->dclk > dclkmax) {
1357                         timings->dclk = dclkmax;
1358                         fb_timings_dclk(timings);
1359                 }
1360                 break;
1361         case FB_VSYNCTIMINGS: /* vrefresh driven */
1362                 timings->vfreq = val;
1363                 fb_timings_vfreq(timings);
1364                 break;
1365         case FB_HSYNCTIMINGS: /* hsync driven */
1366                 timings->hfreq = val;
1367                 fb_timings_hfreq(timings);
1368                 break;
1369         case FB_DCLKTIMINGS: /* pixelclock driven */
1370                 timings->dclk = PICOS2KHZ(val) * 1000;
1371                 fb_timings_dclk(timings);
1372                 break;
1373         default:
1374                 err = -EINVAL;
1375
1376         }
1377
1378         if (err || (!(flags & FB_IGNOREMON) &&
1379             (timings->vfreq < vfmin || timings->vfreq > vfmax ||
1380              timings->hfreq < hfmin || timings->hfreq > hfmax ||
1381              timings->dclk < dclkmin || timings->dclk > dclkmax))) {
1382                 err = -EINVAL;
1383         } else {
1384                 var->pixclock = KHZ2PICOS(timings->dclk/1000);
1385                 var->hsync_len = (timings->htotal * 8)/100;
1386                 var->right_margin = (timings->hblank/2) - var->hsync_len;
1387                 var->left_margin = timings->hblank - var->right_margin -
1388                         var->hsync_len;
1389                 var->vsync_len = (3 * interlace)/dscan;
1390                 var->lower_margin = (1 * interlace)/dscan;
1391                 var->upper_margin = (timings->vblank * interlace)/dscan -
1392                         (var->vsync_len + var->lower_margin);
1393         }
1394
1395         kfree(timings);
1396         return err;
1397 }
1398
1399 #ifdef CONFIG_VIDEOMODE_HELPERS
1400 int fb_videomode_from_videomode(const struct videomode *vm,
1401                                 struct fb_videomode *fbmode)
1402 {
1403         unsigned int htotal, vtotal;
1404
1405         fbmode->xres = vm->hactive;
1406         fbmode->left_margin = vm->hback_porch;
1407         fbmode->right_margin = vm->hfront_porch;
1408         fbmode->hsync_len = vm->hsync_len;
1409
1410         fbmode->yres = vm->vactive;
1411         fbmode->upper_margin = vm->vback_porch;
1412         fbmode->lower_margin = vm->vfront_porch;
1413         fbmode->vsync_len = vm->vsync_len;
1414
1415         /* prevent division by zero in KHZ2PICOS macro */
1416         fbmode->pixclock = vm->pixelclock ?
1417                         KHZ2PICOS(vm->pixelclock / 1000) : 0;
1418
1419         fbmode->sync = 0;
1420         fbmode->vmode = 0;
1421         if (vm->flags & DISPLAY_FLAGS_HSYNC_HIGH)
1422                 fbmode->sync |= FB_SYNC_HOR_HIGH_ACT;
1423         if (vm->flags & DISPLAY_FLAGS_VSYNC_HIGH)
1424                 fbmode->sync |= FB_SYNC_VERT_HIGH_ACT;
1425         if (vm->flags & DISPLAY_FLAGS_INTERLACED)
1426                 fbmode->vmode |= FB_VMODE_INTERLACED;
1427         if (vm->flags & DISPLAY_FLAGS_DOUBLESCAN)
1428                 fbmode->vmode |= FB_VMODE_DOUBLE;
1429         fbmode->flag = 0;
1430
1431         htotal = vm->hactive + vm->hfront_porch + vm->hback_porch +
1432                  vm->hsync_len;
1433         vtotal = vm->vactive + vm->vfront_porch + vm->vback_porch +
1434                  vm->vsync_len;
1435         /* prevent division by zero */
1436         if (htotal && vtotal) {
1437                 fbmode->refresh = vm->pixelclock / (htotal * vtotal);
1438         /* a mode must have htotal and vtotal != 0 or it is invalid */
1439         } else {
1440                 fbmode->refresh = 0;
1441                 return -EINVAL;
1442         }
1443
1444         return 0;
1445 }
1446 EXPORT_SYMBOL_GPL(fb_videomode_from_videomode);
1447
1448 #ifdef CONFIG_OF
1449 static inline void dump_fb_videomode(const struct fb_videomode *m)
1450 {
1451         pr_debug("fb_videomode = %ux%u@%uHz (%ukHz) %u %u %u %u %u %u %u %u %u\n",
1452                  m->xres, m->yres, m->refresh, m->pixclock, m->left_margin,
1453                  m->right_margin, m->upper_margin, m->lower_margin,
1454                  m->hsync_len, m->vsync_len, m->sync, m->vmode, m->flag);
1455 }
1456
1457 /**
1458  * of_get_fb_videomode - get a fb_videomode from devicetree
1459  * @np: device_node with the timing specification
1460  * @fb: will be set to the return value
1461  * @index: index into the list of display timings in devicetree
1462  *
1463  * DESCRIPTION:
1464  * This function is expensive and should only be used, if only one mode is to be
1465  * read from DT. To get multiple modes start with of_get_display_timings ond
1466  * work with that instead.
1467  */
1468 int of_get_fb_videomode(struct device_node *np, struct fb_videomode *fb,
1469                         int index)
1470 {
1471         struct videomode vm;
1472         int ret;
1473
1474         ret = of_get_videomode(np, &vm, index);
1475         if (ret)
1476                 return ret;
1477
1478         ret = fb_videomode_from_videomode(&vm, fb);
1479         if (ret)
1480                 return ret;
1481
1482         pr_debug("%pOF: got %dx%d display mode from %s\n",
1483                 np, vm.hactive, vm.vactive, np->name);
1484         dump_fb_videomode(fb);
1485
1486         return 0;
1487 }
1488 EXPORT_SYMBOL_GPL(of_get_fb_videomode);
1489 #endif /* CONFIG_OF */
1490 #endif /* CONFIG_VIDEOMODE_HELPERS */
1491
1492 #else
1493 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
1494 {
1495         return 1;
1496 }
1497 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1498 {
1499 }
1500 void fb_edid_add_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1501 {
1502 }
1503 void fb_destroy_modedb(struct fb_videomode *modedb)
1504 {
1505 }
1506 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
1507                 struct fb_info *info)
1508 {
1509         return -EINVAL;
1510 }
1511 #endif /* CONFIG_FB_MODE_HELPERS */
1512
1513 /*
1514  * fb_validate_mode - validates var against monitor capabilities
1515  * @var: pointer to fb_var_screeninfo
1516  * @info: pointer to fb_info
1517  *
1518  * DESCRIPTION:
1519  * Validates video mode against monitor capabilities specified in
1520  * info->monspecs.
1521  *
1522  * REQUIRES:
1523  * A valid info->monspecs.
1524  */
1525 int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
1526 {
1527         u32 hfreq, vfreq, htotal, vtotal, pixclock;
1528         u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
1529
1530         /*
1531          * If monspecs are invalid, use values that are enough
1532          * for 640x480@60
1533          */
1534         if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
1535             !info->monspecs.dclkmax ||
1536             info->monspecs.hfmax < info->monspecs.hfmin ||
1537             info->monspecs.vfmax < info->monspecs.vfmin ||
1538             info->monspecs.dclkmax < info->monspecs.dclkmin) {
1539                 hfmin = 29000; hfmax = 30000;
1540                 vfmin = 60; vfmax = 60;
1541                 dclkmin = 0; dclkmax = 25000000;
1542         } else {
1543                 hfmin = info->monspecs.hfmin;
1544                 hfmax = info->monspecs.hfmax;
1545                 vfmin = info->monspecs.vfmin;
1546                 vfmax = info->monspecs.vfmax;
1547                 dclkmin = info->monspecs.dclkmin;
1548                 dclkmax = info->monspecs.dclkmax;
1549         }
1550
1551         if (!var->pixclock)
1552                 return -EINVAL;
1553         pixclock = PICOS2KHZ(var->pixclock) * 1000;
1554
1555         htotal = var->xres + var->right_margin + var->hsync_len +
1556                 var->left_margin;
1557         vtotal = var->yres + var->lower_margin + var->vsync_len +
1558                 var->upper_margin;
1559
1560         if (var->vmode & FB_VMODE_INTERLACED)
1561                 vtotal /= 2;
1562         if (var->vmode & FB_VMODE_DOUBLE)
1563                 vtotal *= 2;
1564
1565         hfreq = pixclock/htotal;
1566         hfreq = (hfreq + 500) / 1000 * 1000;
1567
1568         vfreq = hfreq/vtotal;
1569
1570         return (vfreq < vfmin || vfreq > vfmax ||
1571                 hfreq < hfmin || hfreq > hfmax ||
1572                 pixclock < dclkmin || pixclock > dclkmax) ?
1573                 -EINVAL : 0;
1574 }
1575
1576 #if defined(CONFIG_FIRMWARE_EDID) && defined(CONFIG_X86)
1577
1578 /*
1579  * We need to ensure that the EDID block is only returned for
1580  * the primary graphics adapter.
1581  */
1582
1583 const unsigned char *fb_firmware_edid(struct device *device)
1584 {
1585         struct pci_dev *dev = NULL;
1586         struct resource *res = NULL;
1587         unsigned char *edid = NULL;
1588
1589         if (device)
1590                 dev = to_pci_dev(device);
1591
1592         if (dev)
1593                 res = &dev->resource[PCI_ROM_RESOURCE];
1594
1595         if (res && res->flags & IORESOURCE_ROM_SHADOW)
1596                 edid = edid_info.dummy;
1597
1598         return edid;
1599 }
1600 #else
1601 const unsigned char *fb_firmware_edid(struct device *device)
1602 {
1603         return NULL;
1604 }
1605 #endif
1606 EXPORT_SYMBOL(fb_firmware_edid);
1607
1608 EXPORT_SYMBOL(fb_parse_edid);
1609 EXPORT_SYMBOL(fb_edid_to_monspecs);
1610 EXPORT_SYMBOL(fb_edid_add_monspecs);
1611 EXPORT_SYMBOL(fb_get_mode);
1612 EXPORT_SYMBOL(fb_validate_mode);
1613 EXPORT_SYMBOL(fb_destroy_modedb);