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_ */ 291