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 <errno.h>
  16 #include <linux/ctype.h>
  17 #include <linux/string.h>
  18
  19 int edid_check_info(struct edid1_info *edid_info)
  20 {
  21         if ((edid_info == NULL) || (edid_info->version == 0))
  22                 return -1;
  23
  24         if (memcmp(edid_info->header, "\x0\xff\xff\xff\xff\xff\xff\x0", 8))
  25                 return -1;
  26
  27         if (edid_info->version == 0xff && edid_info->revision == 0xff)
  28                 return -1;
  29
  30         return 0;
  31 }
  32
  33 int edid_check_checksum(u8 *edid_block)
  34 {
  35         u8 checksum = 0;
  36         int i;
  37
  38         for (i = 0; i < 128; i++)
  39                 checksum += edid_block[i];
  40
  41         return (checksum == 0) ? 0 : -EINVAL;
  42 }
  43
  44 int edid_get_ranges(struct edid1_info *edid, unsigned int *hmin,
  45                     unsigned int *hmax, unsigned int *vmin,
  46                     unsigned int *vmax)
  47 {
  48         int i;
  49         struct edid_monitor_descriptor *monitor;
  50
  51         *hmin = *hmax = *vmin = *vmax = 0;
  52         if (edid_check_info(edid))
  53                 return -1;
  54
  55         for (i = 0; i < ARRAY_SIZE(edid->monitor_details.descriptor); i++) {
  56                 monitor = &edid->monitor_details.descriptor[i];
  57                 if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE) {
  58                         *hmin = monitor->data.range_data.horizontal_min;
  59                         *hmax = monitor->data.range_data.horizontal_max;
  60                         *vmin = monitor->data.range_data.vertical_min;
  61                         *vmax = monitor->data.range_data.vertical_max;
  62                         return 0;
  63                 }
  64         }
  65         return -1;
  66 }
  67
  68 /**
  69  * Snip the tailing whitespace/return of a string.
  70  *
  71  * @param string        The string to be snipped
  72  * @return the snipped string
  73  */
  74 static char *snip(char *string)
  75 {
  76         char *s;
  77
  78         /*
  79          * This is always a 13 character buffer
  80          * and it's not always terminated.
  81          */
  82         string[12] = '\0';
  83         s = &string[strlen(string) - 1];
  84
  85         while (s >= string && (isspace(*s) || *s == '\n' || *s == '\r' ||
  86                         *s == '\0'))
  87                 *(s--) = '\0';
  88
  89         return string;
  90 }
  91
  92 /**
  93  * Print an EDID monitor descriptor block
  94  *
  95  * @param monitor       The EDID monitor descriptor block
  96  * @have_timing         Modifies to 1 if the desciptor contains timing info
  97  */
  98 static void edid_print_dtd(struct edid_monitor_descriptor *monitor,
  99                            unsigned int *have_timing)
 100 {
 101         unsigned char *bytes = (unsigned char *)monitor;
 102         struct edid_detailed_timing *timing =
 103                         (struct edid_detailed_timing *)monitor;
 104
 105         if (bytes[0] == 0 && bytes[1] == 0) {
 106                 if (monitor->type == EDID_MONITOR_DESCRIPTOR_SERIAL)
 107                         printf("Monitor serial number: %s\n",
 108                                snip(monitor->data.string));
 109                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII)
 110                         printf("Monitor ID: %s\n",
 111                                snip(monitor->data.string));
 112                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME)
 113                         printf("Monitor name: %s\n",
 114                                snip(monitor->data.string));
 115                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE)
 116                         printf("Monitor range limits, horizontal sync: "
 117                                "%d-%d kHz, vertical refresh: "
 118                                "%d-%d Hz, max pixel clock: "
 119                                "%d MHz\n",
 120                                monitor->data.range_data.horizontal_min,
 121                                monitor->data.range_data.horizontal_max,
 122                                monitor->data.range_data.vertical_min,
 123                                monitor->data.range_data.vertical_max,
 124                                monitor->data.range_data.pixel_clock_max * 10);
 125         } else {
 126                 uint32_t pixclock, h_active, h_blanking, v_active, v_blanking;
 127                 uint32_t h_total, v_total, vfreq;
 128
 129                 pixclock = EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing);
 130                 h_active = EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing);
 131                 h_blanking = EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing);
 132                 v_active = EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing);
 133                 v_blanking = EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing);
 134
 135                 h_total = h_active + h_blanking;
 136                 v_total = v_active + v_blanking;
 137                 if (v_total * h_total)
 138                         vfreq = pixclock / (v_total * h_total);
 139                 else
 140                         vfreq = 1; /* Error case */
 141                 printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active,
 142                        v_active, h_active > 1000 ? ' ' : '\t', vfreq);
 143                 *have_timing = 1;
 144         }
 145 }
 146
 147 /**
 148  * Get the manufacturer name from an EDID info.
 149  *
 150  * @param edid_info     The EDID info to be printed
 151  * @param name          Returns the string of the manufacturer name
 152  */
 153 static void edid_get_manufacturer_name(struct edid1_info *edid, char *name)
 154 {
 155         name[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid) + 'A' - 1;
 156         name[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid) + 'A' - 1;
 157         name[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid) + 'A' - 1;
 158         name[3] = '\0';
 159 }
 160
 161 void edid_print_info(struct edid1_info *edid_info)
 162 {
 163         int i;
 164         char manufacturer[4];
 165         unsigned int have_timing = 0;
 166         uint32_t serial_number;
 167
 168         if (edid_check_info(edid_info)) {
 169                 printf("Not a valid EDID\n");
 170                 return;
 171         }
 172
 173         printf("EDID version: %d.%d\n",
 174                edid_info->version, edid_info->revision);
 175
 176         printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info));
 177
 178         edid_get_manufacturer_name(edid_info, manufacturer);
 179         printf("Manufacturer: %s\n", manufacturer);
 180
 181         serial_number = EDID1_INFO_SERIAL_NUMBER(*edid_info);
 182         if (serial_number != 0xffffffff) {
 183                 if (strcmp(manufacturer, "MAG") == 0)
 184                         serial_number -= 0x7000000;
 185                 if (strcmp(manufacturer, "OQI") == 0)
 186                         serial_number -= 456150000;
 187                 if (strcmp(manufacturer, "VSC") == 0)
 188                         serial_number -= 640000000;
 189         }
 190         printf("Serial number: %08x\n", serial_number);
 191         printf("Manufactured in week: %d year: %d\n",
 192                edid_info->week, edid_info->year + 1990);
 193
 194         printf("Video input definition: %svoltage level %d%s%s%s%s%s\n",
 195                EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info) ?
 196                "digital signal, " : "analog signal, ",
 197                EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info),
 198                EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info) ?
 199                ", blank to black" : "",
 200                EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info) ?
 201                ", separate sync" : "",
 202                EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info) ?
 203                ", composite sync" : "",
 204                EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info) ?
 205                ", sync on green" : "",
 206                EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info) ?
 207                ", serration v" : "");
 208
 209         printf("Monitor is %s\n",
 210                EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB");
 211
 212         printf("Maximum visible display size: %d cm x %d cm\n",
 213                edid_info->max_size_horizontal,
 214                edid_info->max_size_vertical);
 215
 216         printf("Power management features: %s%s, %s%s, %s%s\n",
 217                EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info) ?
 218                "" : "no ", "active off",
 219                EDID1_INFO_FEATURE_SUSPEND(*edid_info) ? "" : "no ", "suspend",
 220                EDID1_INFO_FEATURE_STANDBY(*edid_info) ? "" : "no ", "standby");
 221
 222         printf("Estabilished timings:\n");
 223         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info))
 224                 printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n");
 225         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info))
 226                 printf("\t720x400\t\t88 Hz (XGA2)\n");
 227         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info))
 228                 printf("\t640x480\t\t60 Hz (VGA)\n");
 229         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info))
 230                 printf("\t640x480\t\t67 Hz (Mac II, Apple)\n");
 231         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info))
 232                 printf("\t640x480\t\t72 Hz (VESA)\n");
 233         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info))
 234                 printf("\t640x480\t\t75 Hz (VESA)\n");
 235         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info))
 236                 printf("\t800x600\t\t56 Hz (VESA)\n");
 237         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info))
 238                 printf("\t800x600\t\t60 Hz (VESA)\n");
 239         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info))
 240                 printf("\t800x600\t\t72 Hz (VESA)\n");
 241         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info))
 242                 printf("\t800x600\t\t75 Hz (VESA)\n");
 243         if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info))
 244                 printf("\t832x624\t\t75 Hz (Mac II)\n");
 245         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info))
 246                 printf("\t1024x768\t87 Hz Interlaced (8514A)\n");
 247         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info))
 248                 printf("\t1024x768\t60 Hz (VESA)\n");
 249         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info))
 250                 printf("\t1024x768\t70 Hz (VESA)\n");
 251         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info))
 252                 printf("\t1024x768\t75 Hz (VESA)\n");
 253         if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info))
 254                 printf("\t1280x1024\t75 (VESA)\n");
 255         if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info))
 256                 printf("\t1152x870\t75 (Mac II)\n");
 257
 258         /* Standard timings. */
 259         printf("Standard timings:\n");
 260         for (i = 0; i < ARRAY_SIZE(edid_info->standard_timings); i++) {
 261                 unsigned int aspect = 10000;
 262                 unsigned int x, y;
 263                 unsigned char xres, vfreq;
 264
 265                 xres = EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info, i);
 266                 vfreq = EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info, i);
 267                 if ((xres != vfreq) ||
 268                     ((xres != 0) && (xres != 1)) ||
 269                     ((vfreq != 0) && (vfreq != 1))) {
 270                         switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info,
 271                                         i)) {
 272                         case ASPECT_625:
 273                                 aspect = 6250;
 274                                 break;
 275                         case ASPECT_75:
 276                                 aspect = 7500;
 277                                 break;
 278                         case ASPECT_8:
 279                                 aspect = 8000;
 280                                 break;
 281                         case ASPECT_5625:
 282                                 aspect = 5625;
 283                                 break;
 284                         }
 285                         x = (xres + 31) * 8;
 286                         y = x * aspect / 10000;
 287                         printf("\t%dx%d%c\t%d Hz\n", x, y,
 288                                x > 1000 ? ' ' : '\t', (vfreq & 0x3f) + 60);
 289                         have_timing = 1;
 290                 }
 291         }
 292
 293         /* Detailed timing information. */
 294         for (i = 0; i < ARRAY_SIZE(edid_info->monitor_details.descriptor);
 295                         i++) {
 296                 edid_print_dtd(&edid_info->monitor_details.descriptor[i],
 297                                &have_timing);
 298         }
 299
 300         if (!have_timing)
 301                 printf("\tNone\n");
 302 }