1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Copyright (c) 2012 The Chromium OS Authors. 4 * 5 * (C) Copyright 2010 6 * Petr Stetiar <ynezz@true.cz> 7 * 8 * Contains stolen code from ddcprobe project which is: 9 * Copyright (C) Nalin Dahyabhai <bigfun@pobox.com> 10 */ 11 12 #ifndef __EDID_H_ 13 #define __EDID_H_ 14 15 #include <linux/types.h> 16 17 /* Size of the EDID data */ 18 #define EDID_SIZE 128 19 #define EDID_EXT_SIZE 256 20 21 /* OUI of HDMI vendor specific data block */ 22 #define HDMI_IEEE_OUI 0x000c03 23 24 #define GET_BIT(_x, _pos) \ 25 (((_x) >> (_pos)) & 1) 26 #define GET_BITS(_x, _pos_msb, _pos_lsb) \ 27 (((_x) >> (_pos_lsb)) & ((1 << ((_pos_msb) - (_pos_lsb) + 1)) - 1)) 28 29 /* Aspect ratios used in EDID info. */ 30 enum edid_aspect { 31 ASPECT_625 = 0, 32 ASPECT_75, 33 ASPECT_8, 34 ASPECT_5625, 35 }; 36 37 /* Detailed timing information used in EDID v1.x */ 38 struct edid_detailed_timing { 39 unsigned char pixel_clock[2]; 40 #define EDID_DETAILED_TIMING_PIXEL_CLOCK(_x) \ 41 (((((uint32_t)(_x).pixel_clock[1]) << 8) + \ 42 (_x).pixel_clock[0]) * 10000) 43 unsigned char horizontal_active; 44 unsigned char horizontal_blanking; 45 unsigned char horizontal_active_blanking_hi; 46 #define EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(_x) \ 47 ((GET_BITS((_x).horizontal_active_blanking_hi, 7, 4) << 8) + \ 48 (_x).horizontal_active) 49 #define EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(_x) \ 50 ((GET_BITS((_x).horizontal_active_blanking_hi, 3, 0) << 8) + \ 51 (_x).horizontal_blanking) 52 unsigned char vertical_active; 53 unsigned char vertical_blanking; 54 unsigned char vertical_active_blanking_hi; 55 #define EDID_DETAILED_TIMING_VERTICAL_ACTIVE(_x) \ 56 ((GET_BITS((_x).vertical_active_blanking_hi, 7, 4) << 8) + \ 57 (_x).vertical_active) 58 #define EDID_DETAILED_TIMING_VERTICAL_BLANKING(_x) \ 59 ((GET_BITS((_x).vertical_active_blanking_hi, 3, 0) << 8) + \ 60 (_x).vertical_blanking) 61 unsigned char hsync_offset; 62 unsigned char hsync_pulse_width; 63 unsigned char vsync_offset_pulse_width; 64 unsigned char hsync_vsync_offset_pulse_width_hi; 65 #define EDID_DETAILED_TIMING_HSYNC_OFFSET(_x) \ 66 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 7, 6) << 8) + \ 67 (_x).hsync_offset) 68 #define EDID_DETAILED_TIMING_HSYNC_PULSE_WIDTH(_x) \ 69 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 5, 4) << 8) + \ 70 (_x).hsync_pulse_width) 71 #define EDID_DETAILED_TIMING_VSYNC_OFFSET(_x) \ 72 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 3, 2) << 4) + \ 73 GET_BITS((_x).vsync_offset_pulse_width, 7, 4)) 74 #define EDID_DETAILED_TIMING_VSYNC_PULSE_WIDTH(_x) \ 75 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 1, 0) << 4) + \ 76 GET_BITS((_x).vsync_offset_pulse_width, 3, 0)) 77 unsigned char himage_size; 78 unsigned char vimage_size; 79 unsigned char himage_vimage_size_hi; 80 #define EDID_DETAILED_TIMING_HIMAGE_SIZE(_x) \ 81 ((GET_BITS((_x).himage_vimage_size_hi, 7, 4) << 8) + (_x).himage_size) 82 #define EDID_DETAILED_TIMING_VIMAGE_SIZE(_x) \ 83 ((GET_BITS((_x).himage_vimage_size_hi, 3, 0) << 8) + (_x).vimage_size) 84 unsigned char hborder; 85 unsigned char vborder; 86 unsigned char flags; 87 #define EDID_DETAILED_TIMING_FLAG_INTERLACED(_x) \ 88 GET_BIT((_x).flags, 7) 89 #define EDID_DETAILED_TIMING_FLAG_STEREO(_x) \ 90 GET_BITS((_x).flags, 6, 5) 91 #define EDID_DETAILED_TIMING_FLAG_DIGITAL_COMPOSITE(_x) \ 92 GET_BITS((_x).flags, 4, 3) 93 #define EDID_DETAILED_TIMING_FLAG_POLARITY(_x) \ 94 GET_BITS((_x).flags, 2, 1) 95 #define EDID_DETAILED_TIMING_FLAG_VSYNC_POLARITY(_x) \ 96 GET_BIT((_x).flags, 2) 97 #define EDID_DETAILED_TIMING_FLAG_HSYNC_POLARITY(_x) \ 98 GET_BIT((_x).flags, 1) 99 #define EDID_DETAILED_TIMING_FLAG_INTERLEAVED(_x) \ 100 GET_BIT((_x).flags, 0) 101 } __attribute__ ((__packed__)); 102 103 enum edid_monitor_descriptor_types { 104 EDID_MONITOR_DESCRIPTOR_SERIAL = 0xff, 105 EDID_MONITOR_DESCRIPTOR_ASCII = 0xfe, 106 EDID_MONITOR_DESCRIPTOR_RANGE = 0xfd, 107 EDID_MONITOR_DESCRIPTOR_NAME = 0xfc, 108 }; 109 110 struct edid_monitor_descriptor { 111 uint16_t zero_flag_1; 112 unsigned char zero_flag_2; 113 unsigned char type; 114 unsigned char zero_flag_3; 115 union { 116 char string[13]; 117 struct { 118 unsigned char vertical_min; 119 unsigned char vertical_max; 120 unsigned char horizontal_min; 121 unsigned char horizontal_max; 122 unsigned char pixel_clock_max; 123 unsigned char gtf_data[8]; 124 } range_data; 125 } data; 126 } __attribute__ ((__packed__)); 127 128 struct edid1_info { 129 unsigned char header[8]; 130 unsigned char manufacturer_name[2]; 131 #define EDID1_INFO_MANUFACTURER_NAME_ZERO(_x) \ 132 GET_BIT(((_x).manufacturer_name[0]), 7) 133 #define EDID1_INFO_MANUFACTURER_NAME_CHAR1(_x) \ 134 GET_BITS(((_x).manufacturer_name[0]), 6, 2) 135 #define EDID1_INFO_MANUFACTURER_NAME_CHAR2(_x) \ 136 ((GET_BITS(((_x).manufacturer_name[0]), 1, 0) << 3) + \ 137 GET_BITS(((_x).manufacturer_name[1]), 7, 5)) 138 #define EDID1_INFO_MANUFACTURER_NAME_CHAR3(_x) \ 139 GET_BITS(((_x).manufacturer_name[1]), 4, 0) 140 unsigned char product_code[2]; 141 #define EDID1_INFO_PRODUCT_CODE(_x) \ 142 (((uint16_t)(_x).product_code[1] << 8) + (_x).product_code[0]) 143 unsigned char serial_number[4]; 144 #define EDID1_INFO_SERIAL_NUMBER(_x) \ 145 (((uint32_t)(_x).serial_number[3] << 24) + \ 146 ((_x).serial_number[2] << 16) + ((_x).serial_number[1] << 8) + \ 147 (_x).serial_number[0]) 148 unsigned char week; 149 unsigned char year; 150 unsigned char version; 151 unsigned char revision; 152 unsigned char video_input_definition; 153 #define EDID1_INFO_VIDEO_INPUT_DIGITAL(_x) \ 154 GET_BIT(((_x).video_input_definition), 7) 155 #define EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(_x) \ 156 GET_BITS(((_x).video_input_definition), 6, 5) 157 #define EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(_x) \ 158 GET_BIT(((_x).video_input_definition), 4) 159 #define EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(_x) \ 160 GET_BIT(((_x).video_input_definition), 3) 161 #define EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(_x) \ 162 GET_BIT(((_x).video_input_definition), 2) 163 #define EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(_x) \ 164 GET_BIT(((_x).video_input_definition), 1) 165 #define EDID1_INFO_VIDEO_INPUT_SERRATION_V(_x) \ 166 GET_BIT(((_x).video_input_definition), 0) 167 unsigned char max_size_horizontal; 168 unsigned char max_size_vertical; 169 unsigned char gamma; 170 unsigned char feature_support; 171 #define EDID1_INFO_FEATURE_STANDBY(_x) \ 172 GET_BIT(((_x).feature_support), 7) 173 #define EDID1_INFO_FEATURE_SUSPEND(_x) \ 174 GET_BIT(((_x).feature_support), 6) 175 #define EDID1_INFO_FEATURE_ACTIVE_OFF(_x) \ 176 GET_BIT(((_x).feature_support), 5) 177 #define EDID1_INFO_FEATURE_DISPLAY_TYPE(_x) \ 178 GET_BITS(((_x).feature_support), 4, 3) 179 #define EDID1_INFO_FEATURE_RGB(_x) \ 180 GET_BIT(((_x).feature_support), 2) 181 #define EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(_x) \ 182 GET_BIT(((_x).feature_support), 1) 183 #define EDID1_INFO_FEATURE_DEFAULT_GTF_SUPPORT(_x) \ 184 GET_BIT(((_x).feature_support), 0) 185 unsigned char color_characteristics[10]; 186 unsigned char established_timings[3]; 187 #define EDID1_INFO_ESTABLISHED_TIMING_720X400_70(_x) \ 188 GET_BIT(((_x).established_timings[0]), 7) 189 #define EDID1_INFO_ESTABLISHED_TIMING_720X400_88(_x) \ 190 GET_BIT(((_x).established_timings[0]), 6) 191 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_60(_x) \ 192 GET_BIT(((_x).established_timings[0]), 5) 193 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_67(_x) \ 194 GET_BIT(((_x).established_timings[0]), 4) 195 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_72(_x) \ 196 GET_BIT(((_x).established_timings[0]), 3) 197 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_75(_x) \ 198 GET_BIT(((_x).established_timings[0]), 2) 199 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_56(_x) \ 200 GET_BIT(((_x).established_timings[0]), 1) 201 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_60(_x) \ 202 GET_BIT(((_x).established_timings[0]), 0) 203 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_72(_x) \ 204 GET_BIT(((_x).established_timings[1]), 7) 205 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_75(_x) \ 206 GET_BIT(((_x).established_timings[1]), 6) 207 #define EDID1_INFO_ESTABLISHED_TIMING_832X624_75(_x) \ 208 GET_BIT(((_x).established_timings[1]), 5) 209 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(_x) \ 210 GET_BIT(((_x).established_timings[1]), 4) 211 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(_x) \ 212 GET_BIT(((_x).established_timings[1]), 3) 213 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(_x) \ 214 GET_BIT(((_x).established_timings[1]), 2) 215 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(_x) \ 216 GET_BIT(((_x).established_timings[1]), 1) 217 #define EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(_x) \ 218 GET_BIT(((_x).established_timings[1]), 0) 219 #define EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(_x) \ 220 GET_BIT(((_x).established_timings[2]), 7) 221 struct { 222 unsigned char xresolution; 223 unsigned char aspect_vfreq; 224 } __attribute__((__packed__)) standard_timings[8]; 225 #define EDID1_INFO_STANDARD_TIMING_XRESOLUTION(_x, _i) \ 226 (((_x).standard_timings[_i]).xresolution) 227 #define EDID1_INFO_STANDARD_TIMING_ASPECT(_x, _i) \ 228 GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 7, 6) 229 #define EDID1_INFO_STANDARD_TIMING_VFREQ(_x, _i) \ 230 GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 5, 0) 231 union { 232 unsigned char timing[72]; 233 struct edid_monitor_descriptor descriptor[4]; 234 } monitor_details; 235 unsigned char extension_flag; 236 unsigned char checksum; 237 } __attribute__ ((__packed__)); 238 239 enum edid_cea861_db_types { 240 EDID_CEA861_DB_AUDIO = 0x01, 241 EDID_CEA861_DB_VIDEO = 0x02, 242 EDID_CEA861_DB_VENDOR = 0x03, 243 EDID_CEA861_DB_SPEAKER = 0x04, 244 }; 245 246 struct edid_cea861_info { 247 unsigned char extension_tag; 248 #define EDID_CEA861_EXTENSION_TAG 0x02 249 unsigned char revision; 250 unsigned char dtd_offset; 251 unsigned char dtd_count; 252 #define EDID_CEA861_SUPPORTS_UNDERSCAN(_x) \ 253 GET_BIT(((_x).dtd_count), 7) 254 #define EDID_CEA861_SUPPORTS_BASIC_AUDIO(_x) \ 255 GET_BIT(((_x).dtd_count), 6) 256 #define EDID_CEA861_SUPPORTS_YUV444(_x) \ 257 GET_BIT(((_x).dtd_count), 5) 258 #define EDID_CEA861_SUPPORTS_YUV422(_x) \ 259 GET_BIT(((_x).dtd_count), 4) 260 #define EDID_CEA861_DTD_COUNT(_x) \ 261 GET_BITS(((_x).dtd_count), 3, 0) 262 unsigned char data[124]; 263 #define EDID_CEA861_DB_TYPE(_x, offset) \ 264 GET_BITS((_x).data[offset], 7, 5) 265 #define EDID_CEA861_DB_LEN(_x, offset) \ 266 GET_BITS((_x).data[offset], 4, 0) 267 } __attribute__ ((__packed__)); 268 269 /** 270 * Print the EDID info. 271 * 272 * @param edid_info The EDID info to be printed 273 */ 274 void edid_print_info(struct edid1_info *edid_info); 275 276 /** 277 * Check the EDID info. 278 * 279 * @param info The EDID info to be checked 280 * @return 0 on valid, or -1 on invalid 281 */ 282 int edid_check_info(struct edid1_info *info); 283 284 /** 285 * Check checksum of a 128 bytes EDID data block 286 * 287 * @param edid_block EDID block data 288 * 289 * @return 0 on success, or a negative errno on error 290 */ 291 int edid_check_checksum(u8 *edid_block); 292 293 /** 294 * Get the horizontal and vertical rate ranges of the monitor. 295 * 296 * @param edid The EDID info 297 * @param hmin Returns the minimum horizontal rate 298 * @param hmax Returns the maxium horizontal rate 299 * @param vmin Returns the minimum vertical rate 300 * @param vmax Returns the maxium vertical rate 301 * @return 0 on success, or -1 on error 302 */ 303 int edid_get_ranges(struct edid1_info *edid, unsigned int *hmin, 304 unsigned int *hmax, unsigned int *vmin, 305 unsigned int *vmax); 306 307 struct display_timing; 308 309 /** 310 * edid_get_timing() - Get basic digital display parameters 311 * 312 * @param buf Buffer containing EDID data 313 * @param buf_size Size of buffer in bytes 314 * @param timing Place to put preferring timing information 315 * @param panel_bits_per_colourp Place to put the number of bits per 316 * colour supported by the panel. This will be set to 317 * -1 if not available 318 * @return 0 if timings are OK, -ve on error 319 */ 320 int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing, 321 int *panel_bits_per_colourp); 322 323 #endif /* __EDID_H_ */ 324