Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
fbmon.c
Go to the documentation of this file.
1 /*
2  * linux/drivers/video/fbmon.c
3  *
4  * Copyright (C) 2002 James Simmons <[email protected]>
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 <[email protected]>
15  *
16  * 3. John Fremlin <[email protected]> and
17  * Ani Joshi <[email protected]>
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 #ifdef CONFIG_PPC_OF
35 #include <asm/prom.h>
36 #include <asm/pci-bridge.h>
37 #endif
38 #include "edid.h"
39 
40 /*
41  * EDID parser
42  */
43 
44 #undef DEBUG /* define this for verbose EDID parsing output */
45 
46 #ifdef DEBUG
47 #define DPRINTK(fmt, args...) printk(fmt,## args)
48 #else
49 #define DPRINTK(fmt, args...)
50 #endif
51 
52 #define FBMON_FIX_HEADER 1
53 #define FBMON_FIX_INPUT 2
54 #define FBMON_FIX_TIMINGS 3
55 
56 #ifdef CONFIG_FB_MODE_HELPERS
57 struct broken_edid {
58  u8 manufacturer[4];
59  u32 model;
60  u32 fix;
61 };
62 
63 static const struct broken_edid brokendb[] = {
64  /* DEC FR-PCXAV-YZ */
65  {
66  .manufacturer = "DEC",
67  .model = 0x073a,
68  .fix = FBMON_FIX_HEADER,
69  },
70  /* ViewSonic PF775a */
71  {
72  .manufacturer = "VSC",
73  .model = 0x5a44,
74  .fix = FBMON_FIX_INPUT,
75  },
76  /* Sharp UXGA? */
77  {
78  .manufacturer = "SHP",
79  .model = 0x138e,
80  .fix = FBMON_FIX_TIMINGS,
81  },
82 };
83 
84 static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
85  0xff, 0xff, 0xff, 0x00
86 };
87 
88 static void copy_string(unsigned char *c, unsigned char *s)
89 {
90  int i;
91  c = c + 5;
92  for (i = 0; (i < 13 && *c != 0x0A); i++)
93  *(s++) = *(c++);
94  *s = 0;
95  while (i-- && (*--s == 0x20)) *s = 0;
96 }
97 
98 static int edid_is_serial_block(unsigned char *block)
99 {
100  if ((block[0] == 0x00) && (block[1] == 0x00) &&
101  (block[2] == 0x00) && (block[3] == 0xff) &&
102  (block[4] == 0x00))
103  return 1;
104  else
105  return 0;
106 }
107 
108 static int edid_is_ascii_block(unsigned char *block)
109 {
110  if ((block[0] == 0x00) && (block[1] == 0x00) &&
111  (block[2] == 0x00) && (block[3] == 0xfe) &&
112  (block[4] == 0x00))
113  return 1;
114  else
115  return 0;
116 }
117 
118 static int edid_is_limits_block(unsigned char *block)
119 {
120  if ((block[0] == 0x00) && (block[1] == 0x00) &&
121  (block[2] == 0x00) && (block[3] == 0xfd) &&
122  (block[4] == 0x00))
123  return 1;
124  else
125  return 0;
126 }
127 
128 static int edid_is_monitor_block(unsigned char *block)
129 {
130  if ((block[0] == 0x00) && (block[1] == 0x00) &&
131  (block[2] == 0x00) && (block[3] == 0xfc) &&
132  (block[4] == 0x00))
133  return 1;
134  else
135  return 0;
136 }
137 
138 static int edid_is_timing_block(unsigned char *block)
139 {
140  if ((block[0] != 0x00) || (block[1] != 0x00) ||
141  (block[2] != 0x00) || (block[4] != 0x00))
142  return 1;
143  else
144  return 0;
145 }
146 
147 static int check_edid(unsigned char *edid)
148 {
149  unsigned char *block = edid + ID_MANUFACTURER_NAME, manufacturer[4];
150  unsigned char *b;
151  u32 model;
152  int i, fix = 0, ret = 0;
153 
154  manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
155  manufacturer[1] = ((block[0] & 0x03) << 3) +
156  ((block[1] & 0xe0) >> 5) + '@';
157  manufacturer[2] = (block[1] & 0x1f) + '@';
158  manufacturer[3] = 0;
159  model = block[2] + (block[3] << 8);
160 
161  for (i = 0; i < ARRAY_SIZE(brokendb); i++) {
162  if (!strncmp(manufacturer, brokendb[i].manufacturer, 4) &&
163  brokendb[i].model == model) {
164  fix = brokendb[i].fix;
165  break;
166  }
167  }
168 
169  switch (fix) {
170  case FBMON_FIX_HEADER:
171  for (i = 0; i < 8; i++) {
172  if (edid[i] != edid_v1_header[i]) {
173  ret = fix;
174  break;
175  }
176  }
177  break;
178  case FBMON_FIX_INPUT:
179  b = edid + EDID_STRUCT_DISPLAY;
180  /* Only if display is GTF capable will
181  the input type be reset to analog */
182  if (b[4] & 0x01 && b[0] & 0x80)
183  ret = fix;
184  break;
185  case FBMON_FIX_TIMINGS:
186  b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
187  ret = fix;
188 
189  for (i = 0; i < 4; i++) {
190  if (edid_is_limits_block(b)) {
191  ret = 0;
192  break;
193  }
194 
195  b += DETAILED_TIMING_DESCRIPTION_SIZE;
196  }
197 
198  break;
199  }
200 
201  if (ret)
202  printk("fbmon: The EDID Block of "
203  "Manufacturer: %s Model: 0x%x is known to "
204  "be broken,\n", manufacturer, model);
205 
206  return ret;
207 }
208 
209 static void fix_edid(unsigned char *edid, int fix)
210 {
211  int i;
212  unsigned char *b, csum = 0;
213 
214  switch (fix) {
215  case FBMON_FIX_HEADER:
216  printk("fbmon: trying a header reconstruct\n");
217  memcpy(edid, edid_v1_header, 8);
218  break;
219  case FBMON_FIX_INPUT:
220  printk("fbmon: trying to fix input type\n");
221  b = edid + EDID_STRUCT_DISPLAY;
222  b[0] &= ~0x80;
223  edid[127] += 0x80;
224  break;
225  case FBMON_FIX_TIMINGS:
226  printk("fbmon: trying to fix monitor timings\n");
227  b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
228  for (i = 0; i < 4; i++) {
229  if (!(edid_is_serial_block(b) ||
230  edid_is_ascii_block(b) ||
231  edid_is_monitor_block(b) ||
232  edid_is_timing_block(b))) {
233  b[0] = 0x00;
234  b[1] = 0x00;
235  b[2] = 0x00;
236  b[3] = 0xfd;
237  b[4] = 0x00;
238  b[5] = 60; /* vfmin */
239  b[6] = 60; /* vfmax */
240  b[7] = 30; /* hfmin */
241  b[8] = 75; /* hfmax */
242  b[9] = 17; /* pixclock - 170 MHz*/
243  b[10] = 0; /* GTF */
244  break;
245  }
246 
247  b += DETAILED_TIMING_DESCRIPTION_SIZE;
248  }
249 
250  for (i = 0; i < EDID_LENGTH - 1; i++)
251  csum += edid[i];
252 
253  edid[127] = 256 - csum;
254  break;
255  }
256 }
257 
258 static int edid_checksum(unsigned char *edid)
259 {
260  unsigned char csum = 0, all_null = 0;
261  int i, err = 0, fix = check_edid(edid);
262 
263  if (fix)
264  fix_edid(edid, fix);
265 
266  for (i = 0; i < EDID_LENGTH; i++) {
267  csum += edid[i];
268  all_null |= edid[i];
269  }
270 
271  if (csum == 0x00 && all_null) {
272  /* checksum passed, everything's good */
273  err = 1;
274  }
275 
276  return err;
277 }
278 
279 static int edid_check_header(unsigned char *edid)
280 {
281  int i, err = 1, fix = check_edid(edid);
282 
283  if (fix)
284  fix_edid(edid, fix);
285 
286  for (i = 0; i < 8; i++) {
287  if (edid[i] != edid_v1_header[i])
288  err = 0;
289  }
290 
291  return err;
292 }
293 
294 static void parse_vendor_block(unsigned char *block, struct fb_monspecs *specs)
295 {
296  specs->manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
297  specs->manufacturer[1] = ((block[0] & 0x03) << 3) +
298  ((block[1] & 0xe0) >> 5) + '@';
299  specs->manufacturer[2] = (block[1] & 0x1f) + '@';
300  specs->manufacturer[3] = 0;
301  specs->model = block[2] + (block[3] << 8);
302  specs->serial = block[4] + (block[5] << 8) +
303  (block[6] << 16) + (block[7] << 24);
304  specs->year = block[9] + 1990;
305  specs->week = block[8];
306  DPRINTK(" Manufacturer: %s\n", specs->manufacturer);
307  DPRINTK(" Model: %x\n", specs->model);
308  DPRINTK(" Serial#: %u\n", specs->serial);
309  DPRINTK(" Year: %u Week %u\n", specs->year, specs->week);
310 }
311 
312 static void get_dpms_capabilities(unsigned char flags,
313  struct fb_monspecs *specs)
314 {
315  specs->dpms = 0;
316  if (flags & DPMS_ACTIVE_OFF)
317  specs->dpms |= FB_DPMS_ACTIVE_OFF;
318  if (flags & DPMS_SUSPEND)
319  specs->dpms |= FB_DPMS_SUSPEND;
320  if (flags & DPMS_STANDBY)
321  specs->dpms |= FB_DPMS_STANDBY;
322  DPRINTK(" DPMS: Active %s, Suspend %s, Standby %s\n",
323  (flags & DPMS_ACTIVE_OFF) ? "yes" : "no",
324  (flags & DPMS_SUSPEND) ? "yes" : "no",
325  (flags & DPMS_STANDBY) ? "yes" : "no");
326 }
327 
328 static void get_chroma(unsigned char *block, struct fb_monspecs *specs)
329 {
330  int tmp;
331 
332  DPRINTK(" Chroma\n");
333  /* Chromaticity data */
334  tmp = ((block[5] & (3 << 6)) >> 6) | (block[0x7] << 2);
335  tmp *= 1000;
336  tmp += 512;
337  specs->chroma.redx = tmp/1024;
338  DPRINTK(" RedX: 0.%03d ", specs->chroma.redx);
339 
340  tmp = ((block[5] & (3 << 4)) >> 4) | (block[0x8] << 2);
341  tmp *= 1000;
342  tmp += 512;
343  specs->chroma.redy = tmp/1024;
344  DPRINTK("RedY: 0.%03d\n", specs->chroma.redy);
345 
346  tmp = ((block[5] & (3 << 2)) >> 2) | (block[0x9] << 2);
347  tmp *= 1000;
348  tmp += 512;
349  specs->chroma.greenx = tmp/1024;
350  DPRINTK(" GreenX: 0.%03d ", specs->chroma.greenx);
351 
352  tmp = (block[5] & 3) | (block[0xa] << 2);
353  tmp *= 1000;
354  tmp += 512;
355  specs->chroma.greeny = tmp/1024;
356  DPRINTK("GreenY: 0.%03d\n", specs->chroma.greeny);
357 
358  tmp = ((block[6] & (3 << 6)) >> 6) | (block[0xb] << 2);
359  tmp *= 1000;
360  tmp += 512;
361  specs->chroma.bluex = tmp/1024;
362  DPRINTK(" BlueX: 0.%03d ", specs->chroma.bluex);
363 
364  tmp = ((block[6] & (3 << 4)) >> 4) | (block[0xc] << 2);
365  tmp *= 1000;
366  tmp += 512;
367  specs->chroma.bluey = tmp/1024;
368  DPRINTK("BlueY: 0.%03d\n", specs->chroma.bluey);
369 
370  tmp = ((block[6] & (3 << 2)) >> 2) | (block[0xd] << 2);
371  tmp *= 1000;
372  tmp += 512;
373  specs->chroma.whitex = tmp/1024;
374  DPRINTK(" WhiteX: 0.%03d ", specs->chroma.whitex);
375 
376  tmp = (block[6] & 3) | (block[0xe] << 2);
377  tmp *= 1000;
378  tmp += 512;
379  specs->chroma.whitey = tmp/1024;
380  DPRINTK("WhiteY: 0.%03d\n", specs->chroma.whitey);
381 }
382 
383 static void calc_mode_timings(int xres, int yres, int refresh,
384  struct fb_videomode *mode)
385 {
386  struct fb_var_screeninfo *var;
387 
388  var = kzalloc(sizeof(struct fb_var_screeninfo), GFP_KERNEL);
389 
390  if (var) {
391  var->xres = xres;
392  var->yres = yres;
393  fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON,
394  refresh, var, NULL);
395  mode->xres = xres;
396  mode->yres = yres;
397  mode->pixclock = var->pixclock;
398  mode->refresh = refresh;
399  mode->left_margin = var->left_margin;
400  mode->right_margin = var->right_margin;
401  mode->upper_margin = var->upper_margin;
402  mode->lower_margin = var->lower_margin;
403  mode->hsync_len = var->hsync_len;
404  mode->vsync_len = var->vsync_len;
405  mode->vmode = 0;
406  mode->sync = 0;
407  kfree(var);
408  }
409 }
410 
411 static int get_est_timing(unsigned char *block, struct fb_videomode *mode)
412 {
413  int num = 0;
414  unsigned char c;
415 
416  c = block[0];
417  if (c&0x80) {
418  calc_mode_timings(720, 400, 70, &mode[num]);
419  mode[num++].flag = FB_MODE_IS_CALCULATED;
420  DPRINTK(" 720x400@70Hz\n");
421  }
422  if (c&0x40) {
423  calc_mode_timings(720, 400, 88, &mode[num]);
424  mode[num++].flag = FB_MODE_IS_CALCULATED;
425  DPRINTK(" 720x400@88Hz\n");
426  }
427  if (c&0x20) {
428  mode[num++] = vesa_modes[3];
429  DPRINTK(" 640x480@60Hz\n");
430  }
431  if (c&0x10) {
432  calc_mode_timings(640, 480, 67, &mode[num]);
433  mode[num++].flag = FB_MODE_IS_CALCULATED;
434  DPRINTK(" 640x480@67Hz\n");
435  }
436  if (c&0x08) {
437  mode[num++] = vesa_modes[4];
438  DPRINTK(" 640x480@72Hz\n");
439  }
440  if (c&0x04) {
441  mode[num++] = vesa_modes[5];
442  DPRINTK(" 640x480@75Hz\n");
443  }
444  if (c&0x02) {
445  mode[num++] = vesa_modes[7];
446  DPRINTK(" 800x600@56Hz\n");
447  }
448  if (c&0x01) {
449  mode[num++] = vesa_modes[8];
450  DPRINTK(" 800x600@60Hz\n");
451  }
452 
453  c = block[1];
454  if (c&0x80) {
455  mode[num++] = vesa_modes[9];
456  DPRINTK(" 800x600@72Hz\n");
457  }
458  if (c&0x40) {
459  mode[num++] = vesa_modes[10];
460  DPRINTK(" 800x600@75Hz\n");
461  }
462  if (c&0x20) {
463  calc_mode_timings(832, 624, 75, &mode[num]);
464  mode[num++].flag = FB_MODE_IS_CALCULATED;
465  DPRINTK(" 832x624@75Hz\n");
466  }
467  if (c&0x10) {
468  mode[num++] = vesa_modes[12];
469  DPRINTK(" 1024x768@87Hz Interlaced\n");
470  }
471  if (c&0x08) {
472  mode[num++] = vesa_modes[13];
473  DPRINTK(" 1024x768@60Hz\n");
474  }
475  if (c&0x04) {
476  mode[num++] = vesa_modes[14];
477  DPRINTK(" 1024x768@70Hz\n");
478  }
479  if (c&0x02) {
480  mode[num++] = vesa_modes[15];
481  DPRINTK(" 1024x768@75Hz\n");
482  }
483  if (c&0x01) {
484  mode[num++] = vesa_modes[21];
485  DPRINTK(" 1280x1024@75Hz\n");
486  }
487  c = block[2];
488  if (c&0x80) {
489  mode[num++] = vesa_modes[17];
490  DPRINTK(" 1152x870@75Hz\n");
491  }
492  DPRINTK(" Manufacturer's mask: %x\n",c&0x7F);
493  return num;
494 }
495 
496 static int get_std_timing(unsigned char *block, struct fb_videomode *mode,
497  int ver, int rev)
498 {
499  int xres, yres = 0, refresh, ratio, i;
500 
501  xres = (block[0] + 31) * 8;
502  if (xres <= 256)
503  return 0;
504 
505  ratio = (block[1] & 0xc0) >> 6;
506  switch (ratio) {
507  case 0:
508  /* in EDID 1.3 the meaning of 0 changed to 16:10 (prior 1:1) */
509  if (ver < 1 || (ver == 1 && rev < 3))
510  yres = xres;
511  else
512  yres = (xres * 10)/16;
513  break;
514  case 1:
515  yres = (xres * 3)/4;
516  break;
517  case 2:
518  yres = (xres * 4)/5;
519  break;
520  case 3:
521  yres = (xres * 9)/16;
522  break;
523  }
524  refresh = (block[1] & 0x3f) + 60;
525 
526  DPRINTK(" %dx%d@%dHz\n", xres, yres, refresh);
527  for (i = 0; i < VESA_MODEDB_SIZE; i++) {
528  if (vesa_modes[i].xres == xres &&
529  vesa_modes[i].yres == yres &&
530  vesa_modes[i].refresh == refresh) {
531  *mode = vesa_modes[i];
532  mode->flag |= FB_MODE_IS_STANDARD;
533  return 1;
534  }
535  }
536  calc_mode_timings(xres, yres, refresh, mode);
537  return 1;
538 }
539 
540 static int get_dst_timing(unsigned char *block,
541  struct fb_videomode *mode, int ver, int rev)
542 {
543  int j, num = 0;
544 
545  for (j = 0; j < 6; j++, block += STD_TIMING_DESCRIPTION_SIZE)
546  num += get_std_timing(block, &mode[num], ver, rev);
547 
548  return num;
549 }
550 
551 static void get_detailed_timing(unsigned char *block,
552  struct fb_videomode *mode)
553 {
554  mode->xres = H_ACTIVE;
555  mode->yres = V_ACTIVE;
556  mode->pixclock = PIXEL_CLOCK;
557  mode->pixclock /= 1000;
558  mode->pixclock = KHZ2PICOS(mode->pixclock);
559  mode->right_margin = H_SYNC_OFFSET;
560  mode->left_margin = (H_ACTIVE + H_BLANKING) -
561  (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
562  mode->upper_margin = V_BLANKING - V_SYNC_OFFSET -
563  V_SYNC_WIDTH;
564  mode->lower_margin = V_SYNC_OFFSET;
565  mode->hsync_len = H_SYNC_WIDTH;
566  mode->vsync_len = V_SYNC_WIDTH;
567  if (HSYNC_POSITIVE)
568  mode->sync |= FB_SYNC_HOR_HIGH_ACT;
569  if (VSYNC_POSITIVE)
570  mode->sync |= FB_SYNC_VERT_HIGH_ACT;
571  mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *
572  (V_ACTIVE + V_BLANKING));
573  if (INTERLACED) {
574  mode->yres *= 2;
575  mode->upper_margin *= 2;
576  mode->lower_margin *= 2;
577  mode->vsync_len *= 2;
578  mode->vmode |= FB_VMODE_INTERLACED;
579  }
580  mode->flag = FB_MODE_IS_DETAILED;
581 
582  DPRINTK(" %d MHz ", PIXEL_CLOCK/1000000);
583  DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET,
584  H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING);
585  DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET,
586  V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING);
587  DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-",
588  (VSYNC_POSITIVE) ? "+" : "-");
589 }
590 
602 static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize)
603 {
604  struct fb_videomode *mode, *m;
605  unsigned char *block;
606  int num = 0, i, first = 1;
607  int ver, rev;
608 
609  ver = edid[EDID_STRUCT_VERSION];
610  rev = edid[EDID_STRUCT_REVISION];
611 
612  mode = kzalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
613  if (mode == NULL)
614  return NULL;
615 
616  if (edid == NULL || !edid_checksum(edid) ||
617  !edid_check_header(edid)) {
618  kfree(mode);
619  return NULL;
620  }
621 
622  *dbsize = 0;
623 
624  DPRINTK(" Detailed Timings\n");
625  block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
626  for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
627  if (!(block[0] == 0x00 && block[1] == 0x00)) {
628  get_detailed_timing(block, &mode[num]);
629  if (first) {
630  mode[num].flag |= FB_MODE_IS_FIRST;
631  first = 0;
632  }
633  num++;
634  }
635  }
636 
637  DPRINTK(" Supported VESA Modes\n");
638  block = edid + ESTABLISHED_TIMING_1;
639  num += get_est_timing(block, &mode[num]);
640 
641  DPRINTK(" Standard Timings\n");
642  block = edid + STD_TIMING_DESCRIPTIONS_START;
643  for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE)
644  num += get_std_timing(block, &mode[num], ver, rev);
645 
646  block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
647  for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
648  if (block[0] == 0x00 && block[1] == 0x00 && block[3] == 0xfa)
649  num += get_dst_timing(block + 5, &mode[num], ver, rev);
650  }
651 
652  /* Yikes, EDID data is totally useless */
653  if (!num) {
654  kfree(mode);
655  return NULL;
656  }
657 
658  *dbsize = num;
659  m = kmalloc(num * sizeof(struct fb_videomode), GFP_KERNEL);
660  if (!m)
661  return mode;
662  memmove(m, mode, num * sizeof(struct fb_videomode));
663  kfree(mode);
664  return m;
665 }
666 
674 void fb_destroy_modedb(struct fb_videomode *modedb)
675 {
676  kfree(modedb);
677 }
678 
679 static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
680 {
681  int i, retval = 1;
682  unsigned char *block;
683 
684  block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
685 
686  DPRINTK(" Monitor Operating Limits: ");
687 
688  for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
689  if (edid_is_limits_block(block)) {
690  specs->hfmin = H_MIN_RATE * 1000;
691  specs->hfmax = H_MAX_RATE * 1000;
692  specs->vfmin = V_MIN_RATE;
693  specs->vfmax = V_MAX_RATE;
694  specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;
695  specs->gtf = (GTF_SUPPORT) ? 1 : 0;
696  retval = 0;
697  DPRINTK("From EDID\n");
698  break;
699  }
700  }
701 
702  /* estimate monitor limits based on modes supported */
703  if (retval) {
704  struct fb_videomode *modes, *mode;
705  int num_modes, hz, hscan, pixclock;
706  int vtotal, htotal;
707 
708  modes = fb_create_modedb(edid, &num_modes);
709  if (!modes) {
710  DPRINTK("None Available\n");
711  return 1;
712  }
713 
714  retval = 0;
715  for (i = 0; i < num_modes; i++) {
716  mode = &modes[i];
717  pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
718  htotal = mode->xres + mode->right_margin + mode->hsync_len
719  + mode->left_margin;
720  vtotal = mode->yres + mode->lower_margin + mode->vsync_len
721  + mode->upper_margin;
722 
723  if (mode->vmode & FB_VMODE_INTERLACED)
724  vtotal /= 2;
725 
726  if (mode->vmode & FB_VMODE_DOUBLE)
727  vtotal *= 2;
728 
729  hscan = (pixclock + htotal / 2) / htotal;
730  hscan = (hscan + 500) / 1000 * 1000;
731  hz = (hscan + vtotal / 2) / vtotal;
732 
733  if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
734  specs->dclkmax = pixclock;
735 
736  if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
737  specs->dclkmin = pixclock;
738 
739  if (specs->hfmax == 0 || specs->hfmax < hscan)
740  specs->hfmax = hscan;
741 
742  if (specs->hfmin == 0 || specs->hfmin > hscan)
743  specs->hfmin = hscan;
744 
745  if (specs->vfmax == 0 || specs->vfmax < hz)
746  specs->vfmax = hz;
747 
748  if (specs->vfmin == 0 || specs->vfmin > hz)
749  specs->vfmin = hz;
750  }
751  DPRINTK("Extrapolated\n");
752  fb_destroy_modedb(modes);
753  }
754  DPRINTK(" H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",
755  specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,
756  specs->vfmax, specs->dclkmax/1000000);
757  return retval;
758 }
759 
760 static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
761 {
762  unsigned char c, *block;
763 
764  block = edid + EDID_STRUCT_DISPLAY;
765 
766  fb_get_monitor_limits(edid, specs);
767 
768  c = block[0] & 0x80;
769  specs->input = 0;
770  if (c) {
771  specs->input |= FB_DISP_DDI;
772  DPRINTK(" Digital Display Input");
773  } else {
774  DPRINTK(" Analog Display Input: Input Voltage - ");
775  switch ((block[0] & 0x60) >> 5) {
776  case 0:
777  DPRINTK("0.700V/0.300V");
778  specs->input |= FB_DISP_ANA_700_300;
779  break;
780  case 1:
781  DPRINTK("0.714V/0.286V");
782  specs->input |= FB_DISP_ANA_714_286;
783  break;
784  case 2:
785  DPRINTK("1.000V/0.400V");
786  specs->input |= FB_DISP_ANA_1000_400;
787  break;
788  case 3:
789  DPRINTK("0.700V/0.000V");
790  specs->input |= FB_DISP_ANA_700_000;
791  break;
792  }
793  }
794  DPRINTK("\n Sync: ");
795  c = block[0] & 0x10;
796  if (c)
797  DPRINTK(" Configurable signal level\n");
798  c = block[0] & 0x0f;
799  specs->signal = 0;
800  if (c & 0x10) {
801  DPRINTK("Blank to Blank ");
802  specs->signal |= FB_SIGNAL_BLANK_BLANK;
803  }
804  if (c & 0x08) {
805  DPRINTK("Separate ");
806  specs->signal |= FB_SIGNAL_SEPARATE;
807  }
808  if (c & 0x04) {
809  DPRINTK("Composite ");
810  specs->signal |= FB_SIGNAL_COMPOSITE;
811  }
812  if (c & 0x02) {
813  DPRINTK("Sync on Green ");
814  specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
815  }
816  if (c & 0x01) {
817  DPRINTK("Serration on ");
818  specs->signal |= FB_SIGNAL_SERRATION_ON;
819  }
820  DPRINTK("\n");
821  specs->max_x = block[1];
822  specs->max_y = block[2];
823  DPRINTK(" Max H-size in cm: ");
824  if (specs->max_x)
825  DPRINTK("%d\n", specs->max_x);
826  else
827  DPRINTK("variable\n");
828  DPRINTK(" Max V-size in cm: ");
829  if (specs->max_y)
830  DPRINTK("%d\n", specs->max_y);
831  else
832  DPRINTK("variable\n");
833 
834  c = block[3];
835  specs->gamma = c+100;
836  DPRINTK(" Gamma: ");
837  DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
838 
839  get_dpms_capabilities(block[4], specs);
840 
841  switch ((block[4] & 0x18) >> 3) {
842  case 0:
843  DPRINTK(" Monochrome/Grayscale\n");
844  specs->input |= FB_DISP_MONO;
845  break;
846  case 1:
847  DPRINTK(" RGB Color Display\n");
848  specs->input |= FB_DISP_RGB;
849  break;
850  case 2:
851  DPRINTK(" Non-RGB Multicolor Display\n");
852  specs->input |= FB_DISP_MULTI;
853  break;
854  default:
855  DPRINTK(" Unknown\n");
856  specs->input |= FB_DISP_UNKNOWN;
857  break;
858  }
859 
860  get_chroma(block, specs);
861 
862  specs->misc = 0;
863  c = block[4] & 0x7;
864  if (c & 0x04) {
865  DPRINTK(" Default color format is primary\n");
866  specs->misc |= FB_MISC_PRIM_COLOR;
867  }
868  if (c & 0x02) {
869  DPRINTK(" First DETAILED Timing is preferred\n");
870  specs->misc |= FB_MISC_1ST_DETAIL;
871  }
872  if (c & 0x01) {
873  printk(" Display is GTF capable\n");
874  specs->gtf = 1;
875  }
876 }
877 
878 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
879 {
880  int i;
881  unsigned char *block;
882 
883  if (edid == NULL || var == NULL)
884  return 1;
885 
886  if (!(edid_checksum(edid)))
887  return 1;
888 
889  if (!(edid_check_header(edid)))
890  return 1;
891 
892  block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
893 
894  for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
895  if (edid_is_timing_block(block)) {
896  var->xres = var->xres_virtual = H_ACTIVE;
897  var->yres = var->yres_virtual = V_ACTIVE;
898  var->height = var->width = 0;
899  var->right_margin = H_SYNC_OFFSET;
900  var->left_margin = (H_ACTIVE + H_BLANKING) -
901  (H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
902  var->upper_margin = V_BLANKING - V_SYNC_OFFSET -
903  V_SYNC_WIDTH;
904  var->lower_margin = V_SYNC_OFFSET;
905  var->hsync_len = H_SYNC_WIDTH;
906  var->vsync_len = V_SYNC_WIDTH;
907  var->pixclock = PIXEL_CLOCK;
908  var->pixclock /= 1000;
909  var->pixclock = KHZ2PICOS(var->pixclock);
910 
911  if (HSYNC_POSITIVE)
912  var->sync |= FB_SYNC_HOR_HIGH_ACT;
913  if (VSYNC_POSITIVE)
914  var->sync |= FB_SYNC_VERT_HIGH_ACT;
915  return 0;
916  }
917  }
918  return 1;
919 }
920 
921 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
922 {
923  unsigned char *block;
924  int i, found = 0;
925 
926  if (edid == NULL)
927  return;
928 
929  if (!(edid_checksum(edid)))
930  return;
931 
932  if (!(edid_check_header(edid)))
933  return;
934 
935  memset(specs, 0, sizeof(struct fb_monspecs));
936 
937  specs->version = edid[EDID_STRUCT_VERSION];
938  specs->revision = edid[EDID_STRUCT_REVISION];
939 
940  DPRINTK("========================================\n");
941  DPRINTK("Display Information (EDID)\n");
942  DPRINTK("========================================\n");
943  DPRINTK(" EDID Version %d.%d\n", (int) specs->version,
944  (int) specs->revision);
945 
946  parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);
947 
948  block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
949  for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
950  if (edid_is_serial_block(block)) {
951  copy_string(block, specs->serial_no);
952  DPRINTK(" Serial Number: %s\n", specs->serial_no);
953  } else if (edid_is_ascii_block(block)) {
954  copy_string(block, specs->ascii);
955  DPRINTK(" ASCII Block: %s\n", specs->ascii);
956  } else if (edid_is_monitor_block(block)) {
957  copy_string(block, specs->monitor);
958  DPRINTK(" Monitor Name: %s\n", specs->monitor);
959  }
960  }
961 
962  DPRINTK(" Display Characteristics:\n");
963  get_monspecs(edid, specs);
964 
965  specs->modedb = fb_create_modedb(edid, &specs->modedb_len);
966 
967  /*
968  * Workaround for buggy EDIDs that sets that the first
969  * detailed timing is preferred but has not detailed
970  * timing specified
971  */
972  for (i = 0; i < specs->modedb_len; i++) {
973  if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {
974  found = 1;
975  break;
976  }
977  }
978 
979  if (!found)
980  specs->misc &= ~FB_MISC_1ST_DETAIL;
981 
982  DPRINTK("========================================\n");
983 }
984 
990 void fb_edid_add_monspecs(unsigned char *edid, struct fb_monspecs *specs)
991 {
992  unsigned char *block;
993  struct fb_videomode *m;
994  int num = 0, i;
995  u8 svd[64], edt[(128 - 4) / DETAILED_TIMING_DESCRIPTION_SIZE];
996  u8 pos = 4, svd_n = 0;
997 
998  if (!edid)
999  return;
1000 
1001  if (!edid_checksum(edid))
1002  return;
1003 
1004  if (edid[0] != 0x2 ||
1005  edid[2] < 4 || edid[2] > 128 - DETAILED_TIMING_DESCRIPTION_SIZE)
1006  return;
1007 
1008  DPRINTK(" Short Video Descriptors\n");
1009 
1010  while (pos < edid[2]) {
1011  u8 len = edid[pos] & 0x1f, type = (edid[pos] >> 5) & 7;
1012  pr_debug("Data block %u of %u bytes\n", type, len);
1013  if (type == 2)
1014  for (i = pos; i < pos + len; i++) {
1015  u8 idx = edid[pos + i] & 0x7f;
1016  svd[svd_n++] = idx;
1017  pr_debug("N%sative mode #%d\n",
1018  edid[pos + i] & 0x80 ? "" : "on-n", idx);
1019  }
1020  pos += len + 1;
1021  }
1022 
1023  block = edid + edid[2];
1024 
1025  DPRINTK(" Extended Detailed Timings\n");
1026 
1027  for (i = 0; i < (128 - edid[2]) / DETAILED_TIMING_DESCRIPTION_SIZE;
1028  i++, block += DETAILED_TIMING_DESCRIPTION_SIZE)
1029  if (PIXEL_CLOCK)
1030  edt[num++] = block - edid;
1031 
1032  /* Yikes, EDID data is totally useless */
1033  if (!(num + svd_n))
1034  return;
1035 
1036  m = kzalloc((specs->modedb_len + num + svd_n) *
1037  sizeof(struct fb_videomode), GFP_KERNEL);
1038 
1039  if (!m)
1040  return;
1041 
1042  memcpy(m, specs->modedb, specs->modedb_len * sizeof(struct fb_videomode));
1043 
1044  for (i = specs->modedb_len; i < specs->modedb_len + num; i++) {
1045  get_detailed_timing(edid + edt[i - specs->modedb_len], &m[i]);
1046  if (i == specs->modedb_len)
1047  m[i].flag |= FB_MODE_IS_FIRST;
1048  pr_debug("Adding %ux%u@%u\n", m[i].xres, m[i].yres, m[i].refresh);
1049  }
1050 
1051  for (i = specs->modedb_len + num; i < specs->modedb_len + num + svd_n; i++) {
1052  int idx = svd[i - specs->modedb_len - num];
1053  if (!idx || idx > 63) {
1054  pr_warning("Reserved SVD code %d\n", idx);
1055  } else if (idx > ARRAY_SIZE(cea_modes) || !cea_modes[idx].xres) {
1056  pr_warning("Unimplemented SVD code %d\n", idx);
1057  } else {
1058  memcpy(&m[i], cea_modes + idx, sizeof(m[i]));
1059  pr_debug("Adding SVD #%d: %ux%u@%u\n", idx,
1060  m[i].xres, m[i].yres, m[i].refresh);
1061  }
1062  }
1063 
1064  kfree(specs->modedb);
1065  specs->modedb = m;
1066  specs->modedb_len = specs->modedb_len + num + svd_n;
1067 }
1068 
1069 /*
1070  * VESA Generalized Timing Formula (GTF)
1071  */
1072 
1073 #define FLYBACK 550
1074 #define V_FRONTPORCH 1
1075 #define H_OFFSET 40
1076 #define H_SCALEFACTOR 20
1077 #define H_BLANKSCALE 128
1078 #define H_GRADIENT 600
1079 #define C_VAL 30
1080 #define M_VAL 300
1081 
1082 struct __fb_timings {
1083  u32 dclk;
1084  u32 hfreq;
1085  u32 vfreq;
1086  u32 hactive;
1087  u32 vactive;
1088  u32 hblank;
1089  u32 vblank;
1090  u32 htotal;
1091  u32 vtotal;
1092 };
1093 
1109 static u32 fb_get_vblank(u32 hfreq)
1110 {
1111  u32 vblank;
1112 
1113  vblank = (hfreq * FLYBACK)/1000;
1114  vblank = (vblank + 500)/1000;
1115  return (vblank + V_FRONTPORCH);
1116 }
1117 
1138 static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
1139 {
1140  u32 c_val, m_val, duty_cycle, hblank;
1141 
1142  c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 +
1143  H_SCALEFACTOR) * 1000;
1144  m_val = (H_BLANKSCALE * H_GRADIENT)/256;
1145  m_val = (m_val * 1000000)/hfreq;
1146  duty_cycle = c_val - m_val;
1147  hblank = (xres * duty_cycle)/(100000 - duty_cycle);
1148  return (hblank);
1149 }
1150 
1172 static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)
1173 {
1174  u32 duty_cycle, h_period, hblank;
1175 
1176  dclk /= 1000;
1177  h_period = 100 - C_VAL;
1178  h_period *= h_period;
1179  h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);
1180  h_period *= 10000;
1181 
1182  h_period = int_sqrt(h_period);
1183  h_period -= (100 - C_VAL) * 100;
1184  h_period *= 1000;
1185  h_period /= 2 * M_VAL;
1186 
1187  duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;
1188  hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;
1189  hblank &= ~15;
1190  return (hblank);
1191 }
1192 
1206 static u32 fb_get_hfreq(u32 vfreq, u32 yres)
1207 {
1208  u32 divisor, hfreq;
1209 
1210  divisor = (1000000 - (vfreq * FLYBACK))/1000;
1211  hfreq = (yres + V_FRONTPORCH) * vfreq * 1000;
1212  return (hfreq/divisor);
1213 }
1214 
1215 static void fb_timings_vfreq(struct __fb_timings *timings)
1216 {
1217  timings->hfreq = fb_get_hfreq(timings->vfreq, timings->vactive);
1218  timings->vblank = fb_get_vblank(timings->hfreq);
1219  timings->vtotal = timings->vactive + timings->vblank;
1220  timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1221  timings->hactive);
1222  timings->htotal = timings->hactive + timings->hblank;
1223  timings->dclk = timings->htotal * timings->hfreq;
1224 }
1225 
1226 static void fb_timings_hfreq(struct __fb_timings *timings)
1227 {
1228  timings->vblank = fb_get_vblank(timings->hfreq);
1229  timings->vtotal = timings->vactive + timings->vblank;
1230  timings->vfreq = timings->hfreq/timings->vtotal;
1231  timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq,
1232  timings->hactive);
1233  timings->htotal = timings->hactive + timings->hblank;
1234  timings->dclk = timings->htotal * timings->hfreq;
1235 }
1236 
1237 static void fb_timings_dclk(struct __fb_timings *timings)
1238 {
1239  timings->hblank = fb_get_hblank_by_dclk(timings->dclk,
1240  timings->hactive);
1241  timings->htotal = timings->hactive + timings->hblank;
1242  timings->hfreq = timings->dclk/timings->htotal;
1243  timings->vblank = fb_get_vblank(timings->hfreq);
1244  timings->vtotal = timings->vactive + timings->vblank;
1245  timings->vfreq = timings->hfreq/timings->vtotal;
1246 }
1247 
1248 /*
1249  * fb_get_mode - calculates video mode using VESA GTF
1250  * @flags: if: 0 - maximize vertical refresh rate
1251  * 1 - vrefresh-driven calculation;
1252  * 2 - hscan-driven calculation;
1253  * 3 - pixelclock-driven calculation;
1254  * @val: depending on @flags, ignored, vrefresh, hsync or pixelclock
1255  * @var: pointer to fb_var_screeninfo
1256  * @info: pointer to fb_info
1257  *
1258  * DESCRIPTION:
1259  * Calculates video mode based on monitor specs using VESA GTF.
1260  * The GTF is best for VESA GTF compliant monitors but is
1261  * specifically formulated to work for older monitors as well.
1262  *
1263  * If @flag==0, the function will attempt to maximize the
1264  * refresh rate. Otherwise, it will calculate timings based on
1265  * the flag and accompanying value.
1266  *
1267  * If FB_IGNOREMON bit is set in @flags, monitor specs will be
1268  * ignored and @var will be filled with the calculated timings.
1269  *
1270  * All calculations are based on the VESA GTF Spreadsheet
1271  * available at VESA's public ftp (http://www.vesa.org).
1272  *
1273  * NOTES:
1274  * The timings generated by the GTF will be different from VESA
1275  * DMT. It might be a good idea to keep a table of standard
1276  * VESA modes as well. The GTF may also not work for some displays,
1277  * such as, and especially, analog TV.
1278  *
1279  * REQUIRES:
1280  * A valid info->monspecs, otherwise 'safe numbers' will be used.
1281  */
1282 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)
1283 {
1284  struct __fb_timings *timings;
1285  u32 interlace = 1, dscan = 1;
1286  u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;
1287 
1288 
1289  timings = kzalloc(sizeof(struct __fb_timings), GFP_KERNEL);
1290 
1291  if (!timings)
1292  return -ENOMEM;
1293 
1294  /*
1295  * If monspecs are invalid, use values that are enough
1296  * for 640x480@60
1297  */
1298  if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||
1299  !info->monspecs.dclkmax ||
1300  info->monspecs.hfmax < info->monspecs.hfmin ||
1301  info->monspecs.vfmax < info->monspecs.vfmin ||
1302  info->monspecs.dclkmax < info->monspecs.dclkmin) {
1303  hfmin = 29000; hfmax = 30000;
1304  vfmin = 60; vfmax = 60;
1305  dclkmin = 0; dclkmax = 25000000;
1306  } else {
1307  hfmin = info->monspecs.hfmin;
1308  hfmax = info->monspecs.hfmax;
1309  vfmin = info->monspecs.vfmin;
1310  vfmax = info->monspecs.vfmax;
1311  dclkmin = info->monspecs.dclkmin;
1312  dclkmax = info->monspecs.dclkmax;
1313  }
1314 
1315  timings->hactive = var->xres;
1316  timings->vactive = var->yres;
1317  if (var->vmode & FB_VMODE_INTERLACED) {
1318  timings->vactive /= 2;
1319  interlace = 2;
1320  }
1321  if (var->vmode & FB_VMODE_DOUBLE) {
1322  timings->vactive *= 2;
1323  dscan = 2;
1324  }
1325 
1326  switch (flags & ~FB_IGNOREMON) {
1327  case FB_MAXTIMINGS: /* maximize refresh rate */
1328  timings->hfreq = hfmax;
1329  fb_timings_hfreq(timings);
1330  if (timings->vfreq > vfmax) {
1331  timings->vfreq = vfmax;
1332  fb_timings_vfreq(timings);
1333  }
1334  if (timings->dclk > dclkmax) {
1335  timings->dclk = dclkmax;
1336  fb_timings_dclk(timings);
1337  }
1338  break;
1339  case FB_VSYNCTIMINGS: /* vrefresh driven */
1340  timings->vfreq = val;
1341  fb_timings_vfreq(timings);
1342  break;
1343  case FB_HSYNCTIMINGS: /* hsync driven */
1344  timings->hfreq = val;
1345  fb_timings_hfreq(timings);
1346  break;
1347  case FB_DCLKTIMINGS: /* pixelclock driven */
1348  timings->dclk = PICOS2KHZ(val) * 1000;
1349  fb_timings_dclk(timings);
1350  break;
1351  default:
1352  err = -EINVAL;
1353 
1354  }
1355 
1356  if (err || (!(flags & FB_IGNOREMON) &&
1357  (timings->vfreq < vfmin || timings->vfreq > vfmax ||
1358  timings->hfreq < hfmin || timings->hfreq > hfmax ||
1359  timings->dclk < dclkmin || timings->dclk > dclkmax))) {
1360  err = -EINVAL;
1361  } else {
1362  var->pixclock = KHZ2PICOS(timings->dclk/1000);
1363  var->hsync_len = (timings->htotal * 8)/100;
1364  var->right_margin = (timings->hblank/2) - var->hsync_len;
1365  var->left_margin = timings->hblank - var->right_margin -
1366  var->hsync_len;
1367  var->vsync_len = (3 * interlace)/dscan;
1368  var->lower_margin = (1 * interlace)/dscan;
1369  var->upper_margin = (timings->vblank * interlace)/dscan -
1370  (var->vsync_len + var->lower_margin);
1371  }
1372 
1373  kfree(timings);
1374  return err;
1375 }
1376 #else
1377 int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
1378 {
1379  return 1;
1380 }
1381 void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1382 {
1383  specs = NULL;
1384 }
1385 void fb_edid_add_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1386 {
1387 }
1388 void fb_destroy_modedb(struct fb_videomode *modedb)
1389 {
1390 }
1391 int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
1392  struct fb_info *info)
1393 {
1394  return -EINVAL;
1395 }
1396 #endif /* CONFIG_FB_MODE_HELPERS */
1397 
1398 /*
1399  * fb_validate_mode - validates var against monitor capabilities
1400  * @var: pointer to fb_var_screeninfo
1401  * @info: pointer to fb_info
1402  *
1403  * DESCRIPTION:
1404  * Validates video mode against monitor capabilities specified in
1405  * info->monspecs.
1406  *
1407  * REQUIRES:
1408  * A valid info->monspecs.
1409  */
1410 int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
1411 {
1412  u32 hfreq, vfreq, htotal, vtotal, pixclock;
1413  u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
1414 
1415  /*
1416  * If monspecs are invalid, use values that are enough
1417  * for 640x480@60
1418  */
1419  if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
1420  !info->monspecs.dclkmax ||
1421  info->monspecs.hfmax < info->monspecs.hfmin ||
1422  info->monspecs.vfmax < info->monspecs.vfmin ||
1423  info->monspecs.dclkmax < info->monspecs.dclkmin) {
1424  hfmin = 29000; hfmax = 30000;
1425  vfmin = 60; vfmax = 60;
1426  dclkmin = 0; dclkmax = 25000000;
1427  } else {
1428  hfmin = info->monspecs.hfmin;
1429  hfmax = info->monspecs.hfmax;
1430  vfmin = info->monspecs.vfmin;
1431  vfmax = info->monspecs.vfmax;
1432  dclkmin = info->monspecs.dclkmin;
1433  dclkmax = info->monspecs.dclkmax;
1434  }
1435 
1436  if (!var->pixclock)
1437  return -EINVAL;
1438  pixclock = PICOS2KHZ(var->pixclock) * 1000;
1439 
1440  htotal = var->xres + var->right_margin + var->hsync_len +
1441  var->left_margin;
1442  vtotal = var->yres + var->lower_margin + var->vsync_len +
1443  var->upper_margin;
1444 
1445  if (var->vmode & FB_VMODE_INTERLACED)
1446  vtotal /= 2;
1447  if (var->vmode & FB_VMODE_DOUBLE)
1448  vtotal *= 2;
1449 
1450  hfreq = pixclock/htotal;
1451  hfreq = (hfreq + 500) / 1000 * 1000;
1452 
1453  vfreq = hfreq/vtotal;
1454 
1455  return (vfreq < vfmin || vfreq > vfmax ||
1456  hfreq < hfmin || hfreq > hfmax ||
1457  pixclock < dclkmin || pixclock > dclkmax) ?
1458  -EINVAL : 0;
1459 }
1460 
1461 #if defined(CONFIG_FIRMWARE_EDID) && defined(CONFIG_X86)
1462 
1463 /*
1464  * We need to ensure that the EDID block is only returned for
1465  * the primary graphics adapter.
1466  */
1467 
1468 const unsigned char *fb_firmware_edid(struct device *device)
1469 {
1470  struct pci_dev *dev = NULL;
1471  struct resource *res = NULL;
1472  unsigned char *edid = NULL;
1473 
1474  if (device)
1475  dev = to_pci_dev(device);
1476 
1477  if (dev)
1478  res = &dev->resource[PCI_ROM_RESOURCE];
1479 
1480  if (res && res->flags & IORESOURCE_ROM_SHADOW)
1481  edid = edid_info.dummy;
1482 
1483  return edid;
1484 }
1485 #else
1486 const unsigned char *fb_firmware_edid(struct device *device)
1487 {
1488  return NULL;
1489 }
1490 #endif
1491 EXPORT_SYMBOL(fb_firmware_edid);
1492 
1493 EXPORT_SYMBOL(fb_parse_edid);
1494 EXPORT_SYMBOL(fb_edid_to_monspecs);
1495 EXPORT_SYMBOL(fb_edid_add_monspecs);
1496 EXPORT_SYMBOL(fb_get_mode);
1497 EXPORT_SYMBOL(fb_validate_mode);
1498 EXPORT_SYMBOL(fb_destroy_modedb);
Generated on Thu Jan 10 2013 14:40:17 for Linux Kernel by   doxygen 1.8.2