common/edid.c

   1 /*
   2  * Copyright (c) 2012 The Chromium OS Authors.
   3  *
   4  * (C) Copyright 2010
   5  * Petr Stetiar <ynezz@true.cz>
   6  *
   7  * SPDX-License-Identifier:     GPL-2.0+
   8  *
   9  * Contains stolen code from ddcprobe project which is:
  10  * Copyright (C) Nalin Dahyabhai <bigfun@pobox.com>
  11  */
  12
  13 #include <common.h>
  14 #include <edid.h>
  15 #include <linux/ctype.h>
  16 #include <linux/string.h>
  17
  18 int edid_check_info(struct edid1_info *edid_info)
  19 {
  20         if ((edid_info == NULL) || (edid_info->version == 0))
  21                 return -1;
  22
  23         if (memcmp(edid_info->header, "\x0\xff\xff\xff\xff\xff\xff\x0", 8))
  24                 return -1;
  25
  26         if (edid_info->version == 0xff && edid_info->revision == 0xff)
  27                 return -1;
  28
  29         return 0;
  30 }
  31
  32 int edid_get_ranges(struct edid1_info *edid, unsigned int *hmin,
  33                     unsigned int *hmax, unsigned int *vmin,
  34                     unsigned int *vmax)
  35 {
  36         int i;
  37         struct edid_monitor_descriptor *monitor;
  38
  39         *hmin = *hmax = *vmin = *vmax = 0;
  40         if (edid_check_info(edid))
  41                 return -1;
  42
  43         for (i = 0; i < ARRAY_SIZE(edid->monitor_details.descriptor); i++) {
  44                 monitor = &edid->monitor_details.descriptor[i];
  45                 if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE) {
  46                         *hmin = monitor->data.range_data.horizontal_min;
  47                         *hmax = monitor->data.range_data.horizontal_max;
  48                         *vmin = monitor->data.range_data.vertical_min;
  49                         *vmax = monitor->data.range_data.vertical_max;
  50                         return 0;
  51                 }
  52         }
  53         return -1;
  54 }
  55
  56 /**
  57  * Snip the tailing whitespace/return of a string.
  58  *
  59  * @param string        The string to be snipped
  60  * @return the snipped string
  61  */
  62 static char *snip(char *string)
  63 {
  64         char *s;
  65
  66         /*
  67          * This is always a 13 character buffer
  68          * and it's not always terminated.
  69          */
  70         string[12] = '\0';
  71         s = &string[strlen(string) - 1];
  72
  73         while (s >= string && (isspace(*s) || *s == '\n' || *s == '\r' ||
  74                         *s == '\0'))
  75                 *(s--) = '\0';
  76
  77         return string;
  78 }
  79
  80 /**
  81  * Print an EDID monitor descriptor block
  82  *
  83  * @param monitor       The EDID monitor descriptor block
  84  * @have_timing         Modifies to 1 if the desciptor contains timing info
  85  */
  86 static void edid_print_dtd(struct edid_monitor_descriptor *monitor,
  87                            unsigned int *have_timing)
  88 {
  89         unsigned char *bytes = (unsigned char *)monitor;
  90         struct edid_detailed_timing *timing =
  91                         (struct edid_detailed_timing *)monitor;
  92
  93         if (bytes[0] == 0 && bytes[1] == 0) {
  94                 if (monitor->type == EDID_MONITOR_DESCRIPTOR_SERIAL)
  95                         printf("Monitor serial number: %s\n",
  96                                snip(monitor->data.string));
  97                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII)
  98                         printf("Monitor ID: %s\n",
  99                                snip(monitor->data.string));
 100                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME)
 101                         printf("Monitor name: %s\n",
 102                                snip(monitor->data.string));
 103                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE)
 104                         printf("Monitor range limits, horizontal sync: "
 105                                "%d-%d kHz, vertical refresh: "
 106                                "%d-%d Hz, max pixel clock: "
 107                                "%d MHz\n",
 108                                monitor->data.range_data.horizontal_min,
 109                                monitor->data.range_data.horizontal_max,
 110                                monitor->data.range_data.vertical_min,
 111                                monitor->data.range_data.vertical_max,
 112                                monitor->data.range_data.pixel_clock_max * 10);
 113         } else {
 114                 uint32_t pixclock, h_active, h_blanking, v_active, v_blanking;
 115                 uint32_t h_total, v_total, vfreq;
 116
 117                 pixclock = EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing);
 118                 h_active = EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing);
 119                 h_blanking = EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing);
 120                 v_active = EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing);
 121                 v_blanking = EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing);
 122
 123                 h_total = h_active + h_blanking;
 124                 v_total = v_active + v_blanking;
 125                 if (v_total * h_total)
 126                         vfreq = pixclock / (v_total * h_total);
 127                 else
 128                         vfreq = 1; /* Error case */
 129                 printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active,
 130                        v_active, h_active > 1000 ? ' ' : '\t', vfreq);
 131                 *have_timing = 1;
 132         }
 133 }
 134
 135 /**
 136  * Get the manufacturer name from an EDID info.
 137  *
 138  * @param edid_info     The EDID info to be printed
 139  * @param name          Returns the string of the manufacturer name
 140  */
 141 static void edid_get_manufacturer_name(struct edid1_info *edid, char *name)
 142 {
 143         name[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid) + 'A' - 1;
 144         name[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid) + 'A' - 1;
 145         name[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid) + 'A' - 1;
 146         name[3] = '\0';
 147 }
 148
 149 void edid_print_info(struct edid1_info *edid_info)
 150 {
 151         int i;
 152         char manufacturer[4];
 153         unsigned int have_timing = 0;
 154         uint32_t serial_number;
 155
 156         if (edid_check_info(edid_info)) {
 157                 printf("Not a valid EDID\n");
 158                 return;
 159         }
 160
 161         printf("EDID version: %d.%d\n",
 162                edid_info->version, edid_info->revision);
 163
 164         printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info));
 165
 166         edid_get_manufacturer_name(edid_info, manufacturer);
 167         printf("Manufacturer: %s\n", manufacturer);
 168
 169         serial_number = EDID1_INFO_SERIAL_NUMBER(*edid_info);
 170         if (serial_number != 0xffffffff) {
 171                 if (strcmp(manufacturer, "MAG") == 0)
 172                         serial_number -= 0x7000000;
 173                 if (strcmp(manufacturer, "OQI") == 0)
 174                         serial_number -= 456150000;
 175                 if (strcmp(manufacturer, "VSC") == 0)
 176                         serial_number -= 640000000;
 177         }
 178         printf("Serial number: %08x\n", serial_number);
 179         printf("Manufactured in week: %d year: %d\n",
 180                edid_info->week, edid_info->year + 1990);
 181
 182         printf("Video input definition: %svoltage level %d%s%s%s%s%s\n",
 183                EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info) ?
 184                "digital signal, " : "analog signal, ",
 185                EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info),
 186                EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info) ?
 187                ", blank to black" : "",
 188                EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info) ?
 189                ", separate sync" : "",
 190                EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info) ?
 191                ", composite sync" : "",
 192                EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info) ?
 193                ", sync on green" : "",
 194                EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info) ?
 195                ", serration v" : "");
 196
 197         printf("Monitor is %s\n",
 198                EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB");
 199
 200         printf("Maximum visible display size: %d cm x %d cm\n",
 201                edid_info->max_size_horizontal,
 202                edid_info->max_size_vertical);
 203
 204         printf("Power management features: %s%s, %s%s, %s%s\n",
 205                EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info) ?
 206                "" : "no ", "active off",
 207                EDID1_INFO_FEATURE_SUSPEND(*edid_info) ? "" : "no ", "suspend",
 208                EDID1_INFO_FEATURE_STANDBY(*edid_info) ? "" : "no ", "standby");
 209
 210         printf("Estabilished timings:\n");
 211         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info))
 212                 printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n");
 213         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info))
 214                 printf("\t720x400\t\t88 Hz (XGA2)\n");
 215         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info))
 216                 printf("\t640x480\t\t60 Hz (VGA)\n");
 217         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info))
 218                 printf("\t640x480\t\t67 Hz (Mac II, Apple)\n");
 219         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info))
 220                 printf("\t640x480\t\t72 Hz (VESA)\n");
 221         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info))
 222                 printf("\t640x480\t\t75 Hz (VESA)\n");
 223         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info))
 224                 printf("\t800x600\t\t56 Hz (VESA)\n");
 225         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info))
 226                 printf("\t800x600\t\t60 Hz (VESA)\n");
 227         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info))
 228                 printf("\t800x600\t\t72 Hz (VESA)\n");
 229         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info))
 230                 printf("\t800x600\t\t75 Hz (VESA)\n");
 231         if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info))
 232                 printf("\t832x624\t\t75 Hz (Mac II)\n");
 233         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info))
 234                 printf("\t1024x768\t87 Hz Interlaced (8514A)\n");
 235         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info))
 236                 printf("\t1024x768\t60 Hz (VESA)\n");
 237         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info))
 238                 printf("\t1024x768\t70 Hz (VESA)\n");
 239         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info))
 240                 printf("\t1024x768\t75 Hz (VESA)\n");
 241         if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info))
 242                 printf("\t1280x1024\t75 (VESA)\n");
 243         if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info))
 244                 printf("\t1152x870\t75 (Mac II)\n");
 245
 246         /* Standard timings. */
 247         printf("Standard timings:\n");
 248         for (i = 0; i < ARRAY_SIZE(edid_info->standard_timings); i++) {
 249                 unsigned int aspect = 10000;
 250                 unsigned int x, y;
 251                 unsigned char xres, vfreq;
 252
 253                 xres = EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info, i);
 254                 vfreq = EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info, i);
 255                 if ((xres != vfreq) ||
 256                     ((xres != 0) && (xres != 1)) ||
 257                     ((vfreq != 0) && (vfreq != 1))) {
 258                         switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info,
 259                                         i)) {
 260                         case ASPECT_625:
 261                                 aspect = 6250;
 262                                 break;
 263                         case ASPECT_75:
 264                                 aspect = 7500;
 265                                 break;
 266                         case ASPECT_8:
 267                                 aspect = 8000;
 268                                 break;
 269                         case ASPECT_5625:
 270                                 aspect = 5625;
 271                                 break;
 272                         }
 273                         x = (xres + 31) * 8;
 274                         y = x * aspect / 10000;
 275                         printf("\t%dx%d%c\t%d Hz\n", x, y,
 276                                x > 1000 ? ' ' : '\t', (vfreq & 0x3f) + 60);
 277                         have_timing = 1;
 278                 }
 279         }
 280
 281         /* Detailed timing information. */
 282         for (i = 0; i < ARRAY_SIZE(edid_info->monitor_details.descriptor);
 283                         i++) {
 284                 edid_print_dtd(&edid_info->monitor_details.descriptor[i],
 285                                &have_timing);
 286         }
 287
 288         if (!have_timing)
 289                 printf("\tNone\n");
 290 }