include/edid.h

   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 #ifndef __EDID_H_
  14 #define __EDID_H_
  15
  16 #include <linux/types.h>
  17
  18 #define GET_BIT(_x, _pos) \
  19         (((_x) >> (_pos)) & 1)
  20 #define GET_BITS(_x, _pos_msb, _pos_lsb) \
  21         (((_x) >> (_pos_lsb)) & ((1 << ((_pos_msb) - (_pos_lsb) + 1)) - 1))
  22
  23 /* Aspect ratios used in EDID info. */
  24 enum edid_aspect {
  25         ASPECT_625 = 0,
  26         ASPECT_75,
  27         ASPECT_8,
  28         ASPECT_5625,
  29 };
  30
  31 /* Detailed timing information used in EDID v1.x */
  32 struct edid_detailed_timing {
  33         unsigned char pixel_clock[2];
  34 #define EDID_DETAILED_TIMING_PIXEL_CLOCK(_x) \
  35         (((((uint32_t)(_x).pixel_clock[1]) << 8) + \
  36          (_x).pixel_clock[0]) * 10000)
  37         unsigned char horizontal_active;
  38         unsigned char horizontal_blanking;
  39         unsigned char horizontal_active_blanking_hi;
  40 #define EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(_x) \
  41         ((GET_BITS((_x).horizontal_active_blanking_hi, 7, 4) << 8) + \
  42          (_x).horizontal_active)
  43 #define EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(_x) \
  44         ((GET_BITS((_x).horizontal_active_blanking_hi, 3, 0) << 8) + \
  45          (_x).horizontal_blanking)
  46         unsigned char vertical_active;
  47         unsigned char vertical_blanking;
  48         unsigned char vertical_active_blanking_hi;
  49 #define EDID_DETAILED_TIMING_VERTICAL_ACTIVE(_x) \
  50         ((GET_BITS((_x).vertical_active_blanking_hi, 7, 4) << 8) + \
  51          (_x).vertical_active)
  52 #define EDID_DETAILED_TIMING_VERTICAL_BLANKING(_x) \
  53         ((GET_BITS((_x).vertical_active_blanking_hi, 3, 0) << 8) + \
  54          (_x).vertical_blanking)
  55         unsigned char hsync_offset;
  56         unsigned char hsync_pulse_width;
  57         unsigned char vsync_offset_pulse_width;
  58         unsigned char hsync_vsync_offset_pulse_width_hi;
  59 #define EDID_DETAILED_TIMING_HSYNC_OFFSET(_x) \
  60         ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 7, 6) << 8) + \
  61          (_x).hsync_offset)
  62 #define EDID_DETAILED_TIMING_HSYNC_PULSE_WIDTH(_x) \
  63         ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 5, 4) << 8) + \
  64          (_x).hsync_pulse_width)
  65 #define EDID_DETAILED_TIMING_VSYNC_OFFSET(_x) \
  66         ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 3, 2) << 4) + \
  67          GET_BITS((_x).vsync_offset_pulse_width, 7, 4))
  68 #define EDID_DETAILED_TIMING_VSYNC_PULSE_WIDTH(_x) \
  69         ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 1, 0) << 4) + \
  70          GET_BITS((_x).vsync_offset_pulse_width, 3, 0))
  71         unsigned char himage_size;
  72         unsigned char vimage_size;
  73         unsigned char himage_vimage_size_hi;
  74 #define EDID_DETAILED_TIMING_HIMAGE_SIZE(_x) \
  75         ((GET_BITS((_x).himage_vimage_size_hi, 7, 4) << 8) + (_x).himage_size)
  76 #define EDID_DETAILED_TIMING_VIMAGE_SIZE(_x) \
  77         ((GET_BITS((_x).himage_vimage_size_hi, 3, 0) << 8) + (_x).vimage_size)
  78         unsigned char hborder;
  79         unsigned char vborder;
  80         unsigned char flags;
  81 #define EDID_DETAILED_TIMING_FLAG_INTERLACED(_x) \
  82         GET_BIT((_x).flags, 7)
  83 #define EDID_DETAILED_TIMING_FLAG_STEREO(_x) \
  84         GET_BITS((_x).flags, 6, 5)
  85 #define EDID_DETAILED_TIMING_FLAG_DIGITAL_COMPOSITE(_x) \
  86         GET_BITS((_x).flags, 4, 3)
  87 #define EDID_DETAILED_TIMING_FLAG_POLARITY(_x) \
  88         GET_BITS((_x).flags, 2, 1)
  89 #define EDID_DETAILED_TIMING_FLAG_VSYNC_POLARITY(_x) \
  90         GET_BIT((_x).flags, 2)
  91 #define EDID_DETAILED_TIMING_FLAG_HSYNC_POLARITY(_x) \
  92         GET_BIT((_x).flags, 1)
  93 #define EDID_DETAILED_TIMING_FLAG_INTERLEAVED(_x) \
  94         GET_BIT((_x).flags, 0)
  95 } __attribute__ ((__packed__));
  96
  97 enum edid_monitor_descriptor_types {
  98         EDID_MONITOR_DESCRIPTOR_SERIAL = 0xff,
  99         EDID_MONITOR_DESCRIPTOR_ASCII = 0xfe,
 100         EDID_MONITOR_DESCRIPTOR_RANGE = 0xfd,
 101         EDID_MONITOR_DESCRIPTOR_NAME = 0xfc,
 102 };
 103
 104 struct edid_monitor_descriptor {
 105         uint16_t zero_flag_1;
 106         unsigned char zero_flag_2;
 107         unsigned char type;
 108         unsigned char zero_flag_3;
 109         union {
 110                 char string[13];
 111                 struct {
 112                         unsigned char vertical_min;
 113                         unsigned char vertical_max;
 114                         unsigned char horizontal_min;
 115                         unsigned char horizontal_max;
 116                         unsigned char pixel_clock_max;
 117                         unsigned char gtf_data[8];
 118                 } range_data;
 119         } data;
 120 } __attribute__ ((__packed__));
 121
 122 struct edid1_info {
 123         unsigned char header[8];
 124         unsigned char manufacturer_name[2];
 125 #define EDID1_INFO_MANUFACTURER_NAME_ZERO(_x) \
 126         GET_BIT(((_x).manufacturer_name[0]), 7)
 127 #define EDID1_INFO_MANUFACTURER_NAME_CHAR1(_x) \
 128         GET_BITS(((_x).manufacturer_name[0]), 6, 2)
 129 #define EDID1_INFO_MANUFACTURER_NAME_CHAR2(_x) \
 130         ((GET_BITS(((_x).manufacturer_name[0]), 1, 0) << 3) + \
 131          GET_BITS(((_x).manufacturer_name[1]), 7, 5))
 132 #define EDID1_INFO_MANUFACTURER_NAME_CHAR3(_x) \
 133         GET_BITS(((_x).manufacturer_name[1]), 4, 0)
 134         unsigned char product_code[2];
 135 #define EDID1_INFO_PRODUCT_CODE(_x) \
 136         (((uint16_t)(_x).product_code[1] << 8) + (_x).product_code[0])
 137         unsigned char serial_number[4];
 138 #define EDID1_INFO_SERIAL_NUMBER(_x) \
 139         (((uint32_t)(_x).serial_number[3] << 24) + \
 140          ((_x).serial_number[2] << 16) + ((_x).serial_number[1] << 8) + \
 141          (_x).serial_number[0])
 142         unsigned char week;
 143         unsigned char year;
 144         unsigned char version;
 145         unsigned char revision;
 146         unsigned char video_input_definition;
 147 #define EDID1_INFO_VIDEO_INPUT_DIGITAL(_x) \
 148         GET_BIT(((_x).video_input_definition), 7)
 149 #define EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(_x) \
 150         GET_BITS(((_x).video_input_definition), 6, 5)
 151 #define EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(_x) \
 152         GET_BIT(((_x).video_input_definition), 4)
 153 #define EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(_x) \
 154         GET_BIT(((_x).video_input_definition), 3)
 155 #define EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(_x) \
 156         GET_BIT(((_x).video_input_definition), 2)
 157 #define EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(_x) \
 158         GET_BIT(((_x).video_input_definition), 1)
 159 #define EDID1_INFO_VIDEO_INPUT_SERRATION_V(_x) \
 160         GET_BIT(((_x).video_input_definition), 0)
 161         unsigned char max_size_horizontal;
 162         unsigned char max_size_vertical;
 163         unsigned char gamma;
 164         unsigned char feature_support;
 165 #define EDID1_INFO_FEATURE_STANDBY(_x) \
 166         GET_BIT(((_x).feature_support), 7)
 167 #define EDID1_INFO_FEATURE_SUSPEND(_x) \
 168         GET_BIT(((_x).feature_support), 6)
 169 #define EDID1_INFO_FEATURE_ACTIVE_OFF(_x) \
 170         GET_BIT(((_x).feature_support), 5)
 171 #define EDID1_INFO_FEATURE_DISPLAY_TYPE(_x) \
 172         GET_BITS(((_x).feature_support), 4, 3)
 173 #define EDID1_INFO_FEATURE_RGB(_x) \
 174         GET_BIT(((_x).feature_support), 2)
 175 #define EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(_x) \
 176         GET_BIT(((_x).feature_support), 1)
 177 #define EDID1_INFO_FEATURE_DEFAULT_GTF_SUPPORT(_x) \
 178         GET_BIT(((_x).feature_support), 0)
 179         unsigned char color_characteristics[10];
 180         unsigned char established_timings[3];
 181 #define EDID1_INFO_ESTABLISHED_TIMING_720X400_70(_x) \
 182         GET_BIT(((_x).established_timings[0]), 7)
 183 #define EDID1_INFO_ESTABLISHED_TIMING_720X400_88(_x) \
 184         GET_BIT(((_x).established_timings[0]), 6)
 185 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_60(_x) \
 186         GET_BIT(((_x).established_timings[0]), 5)
 187 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_67(_x) \
 188         GET_BIT(((_x).established_timings[0]), 4)
 189 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_72(_x) \
 190         GET_BIT(((_x).established_timings[0]), 3)
 191 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_75(_x) \
 192         GET_BIT(((_x).established_timings[0]), 2)
 193 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_56(_x) \
 194         GET_BIT(((_x).established_timings[0]), 1)
 195 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_60(_x) \
 196         GET_BIT(((_x).established_timings[0]), 0)
 197 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_72(_x) \
 198         GET_BIT(((_x).established_timings[1]), 7)
 199 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_75(_x) \
 200         GET_BIT(((_x).established_timings[1]), 6)
 201 #define EDID1_INFO_ESTABLISHED_TIMING_832X624_75(_x) \
 202         GET_BIT(((_x).established_timings[1]), 5)
 203 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(_x) \
 204         GET_BIT(((_x).established_timings[1]), 4)
 205 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(_x) \
 206         GET_BIT(((_x).established_timings[1]), 3)
 207 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(_x) \
 208         GET_BIT(((_x).established_timings[1]), 2)
 209 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(_x) \
 210         GET_BIT(((_x).established_timings[1]), 1)
 211 #define EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(_x) \
 212         GET_BIT(((_x).established_timings[1]), 0)
 213 #define EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(_x) \
 214         GET_BIT(((_x).established_timings[2]), 7)
 215         struct {
 216                 unsigned char xresolution;
 217                 unsigned char aspect_vfreq;
 218         } __attribute__((__packed__)) standard_timings[8];
 219 #define EDID1_INFO_STANDARD_TIMING_XRESOLUTION(_x, _i) \
 220         (((_x).standard_timings[_i]).xresolution)
 221 #define EDID1_INFO_STANDARD_TIMING_ASPECT(_x, _i) \
 222         GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 7, 6)
 223 #define EDID1_INFO_STANDARD_TIMING_VFREQ(_x, _i) \
 224         GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 5, 0)
 225         union {
 226                 unsigned char timing[72];
 227                 struct edid_monitor_descriptor descriptor[4];
 228         } monitor_details;
 229         unsigned char extension_flag;
 230         unsigned char checksum;
 231 } __attribute__ ((__packed__));
 232
 233 struct edid_cea861_info {
 234         unsigned char extension_tag;
 235 #define EDID_CEA861_EXTENSION_TAG       0x02
 236         unsigned char revision;
 237         unsigned char dtd_offset;
 238         unsigned char dtd_count;
 239 #define EDID_CEA861_SUPPORTS_UNDERSCAN(_x) \
 240         GET_BIT(((_x).dtd_count), 7)
 241 #define EDID_CEA861_SUPPORTS_BASIC_AUDIO(_x) \
 242         GET_BIT(((_x).dtd_count), 6)
 243 #define EDID_CEA861_SUPPORTS_YUV444(_x) \
 244         GET_BIT(((_x).dtd_count), 5)
 245 #define EDID_CEA861_SUPPORTS_YUV422(_x) \
 246         GET_BIT(((_x).dtd_count), 4)
 247 #define EDID_CEA861_DTD_COUNT(_x) \
 248         GET_BITS(((_x).dtd_count), 3, 0)
 249         unsigned char data[124];
 250 } __attribute__ ((__packed__));
 251
 252 /**
 253  * Print the EDID info.
 254  *
 255  * @param edid_info     The EDID info to be printed
 256  */
 257 void edid_print_info(struct edid1_info *edid_info);
 258
 259 /**
 260  * Check the EDID info.
 261  *
 262  * @param info  The EDID info to be checked
 263  * @return 0 on valid, or -1 on invalid
 264  */
 265 int edid_check_info(struct edid1_info *info);
 266
 267 /**
 268  * Check checksum of a 128 bytes EDID data block
 269  *
 270  * @param edid_block    EDID block data
 271  *
 272  * @return 0 on success, or a negative errno on error
 273  */
 274 int edid_check_checksum(u8 *edid_block);
 275
 276 /**
 277  * Get the horizontal and vertical rate ranges of the monitor.
 278  *
 279  * @param edid  The EDID info
 280  * @param hmin  Returns the minimum horizontal rate
 281  * @param hmax  Returns the maxium horizontal rate
 282  * @param vmin  Returns the minimum vertical rate
 283  * @param vmax  Returns the maxium vertical rate
 284  * @return 0 on success, or -1 on error
 285  */
 286 int edid_get_ranges(struct edid1_info *edid, unsigned int *hmin,
 287                     unsigned int *hmax, unsigned int *vmin,
 288                     unsigned int *vmax);
 289
 290 #endif /* __EDID_H_ */