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 /* Size of the EDID data */ 19 #define EDID_SIZE 128 20 #define EDID_EXT_SIZE 256 21 22 /* OUI of HDMI vendor specific data block */ 23 #define HDMI_IEEE_OUI 0x000c03 24 25 #define GET_BIT(_x, _pos) \ 26 (((_x) >> (_pos)) & 1) 27 #define GET_BITS(_x, _pos_msb, _pos_lsb) \ 28 (((_x) >> (_pos_lsb)) & ((1 << ((_pos_msb) - (_pos_lsb) + 1)) - 1)) 29 30 /* Aspect ratios used in EDID info. */ 31 enum edid_aspect { 32 ASPECT_625 = 0, 33 ASPECT_75, 34 ASPECT_8, 35 ASPECT_5625, 36 }; 37 38 /* Detailed timing information used in EDID v1.x */ 39 struct edid_detailed_timing { 40 unsigned char pixel_clock[2]; 41 #define EDID_DETAILED_TIMING_PIXEL_CLOCK(_x) \ 42 (((((uint32_t)(_x).pixel_clock[1]) << 8) + \ 43 (_x).pixel_clock[0]) * 10000) 44 unsigned char horizontal_active; 45 unsigned char horizontal_blanking; 46 unsigned char horizontal_active_blanking_hi; 47 #define EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(_x) \ 48 ((GET_BITS((_x).horizontal_active_blanking_hi, 7, 4) << 8) + \ 49 (_x).horizontal_active) 50 #define EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(_x) \ 51 ((GET_BITS((_x).horizontal_active_blanking_hi, 3, 0) << 8) + \ 52 (_x).horizontal_blanking) 53 unsigned char vertical_active; 54 unsigned char vertical_blanking; 55 unsigned char vertical_active_blanking_hi; 56 #define EDID_DETAILED_TIMING_VERTICAL_ACTIVE(_x) \ 57 ((GET_BITS((_x).vertical_active_blanking_hi, 7, 4) << 8) + \ 58 (_x).vertical_active) 59 #define EDID_DETAILED_TIMING_VERTICAL_BLANKING(_x) \ 60 ((GET_BITS((_x).vertical_active_blanking_hi, 3, 0) << 8) + \ 61 (_x).vertical_blanking) 62 unsigned char hsync_offset; 63 unsigned char hsync_pulse_width; 64 unsigned char vsync_offset_pulse_width; 65 unsigned char hsync_vsync_offset_pulse_width_hi; 66 #define EDID_DETAILED_TIMING_HSYNC_OFFSET(_x) \ 67 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 7, 6) << 8) + \ 68 (_x).hsync_offset) 69 #define EDID_DETAILED_TIMING_HSYNC_PULSE_WIDTH(_x) \ 70 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 5, 4) << 8) + \ 71 (_x).hsync_pulse_width) 72 #define EDID_DETAILED_TIMING_VSYNC_OFFSET(_x) \ 73 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 3, 2) << 4) + \ 74 GET_BITS((_x).vsync_offset_pulse_width, 7, 4)) 75 #define EDID_DETAILED_TIMING_VSYNC_PULSE_WIDTH(_x) \ 76 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 1, 0) << 4) + \ 77 GET_BITS((_x).vsync_offset_pulse_width, 3, 0)) 78 unsigned char himage_size; 79 unsigned char vimage_size; 80 unsigned char himage_vimage_size_hi; 81 #define EDID_DETAILED_TIMING_HIMAGE_SIZE(_x) \ 82 ((GET_BITS((_x).himage_vimage_size_hi, 7, 4) << 8) + (_x).himage_size) 83 #define EDID_DETAILED_TIMING_VIMAGE_SIZE(_x) \ 84 ((GET_BITS((_x).himage_vimage_size_hi, 3, 0) << 8) + (_x).vimage_size) 85 unsigned char hborder; 86 unsigned char vborder; 87 unsigned char flags; 88 #define EDID_DETAILED_TIMING_FLAG_INTERLACED(_x) \ 89 GET_BIT((_x).flags, 7) 90 #define EDID_DETAILED_TIMING_FLAG_STEREO(_x) \ 91 GET_BITS((_x).flags, 6, 5) 92 #define EDID_DETAILED_TIMING_FLAG_DIGITAL_COMPOSITE(_x) \ 93 GET_BITS((_x).flags, 4, 3) 94 #define EDID_DETAILED_TIMING_FLAG_POLARITY(_x) \ 95 GET_BITS((_x).flags, 2, 1) 96 #define EDID_DETAILED_TIMING_FLAG_VSYNC_POLARITY(_x) \ 97 GET_BIT((_x).flags, 2) 98 #define EDID_DETAILED_TIMING_FLAG_HSYNC_POLARITY(_x) \ 99 GET_BIT((_x).flags, 1) 100 #define EDID_DETAILED_TIMING_FLAG_INTERLEAVED(_x) \ 101 GET_BIT((_x).flags, 0) 102 } __attribute__ ((__packed__)); 103 104 enum edid_monitor_descriptor_types { 105 EDID_MONITOR_DESCRIPTOR_SERIAL = 0xff, 106 EDID_MONITOR_DESCRIPTOR_ASCII = 0xfe, 107 EDID_MONITOR_DESCRIPTOR_RANGE = 0xfd, 108 EDID_MONITOR_DESCRIPTOR_NAME = 0xfc, 109 }; 110 111 struct edid_monitor_descriptor { 112 uint16_t zero_flag_1; 113 unsigned char zero_flag_2; 114 unsigned char type; 115 unsigned char zero_flag_3; 116 union { 117 char string[13]; 118 struct { 119 unsigned char vertical_min; 120 unsigned char vertical_max; 121 unsigned char horizontal_min; 122 unsigned char horizontal_max; 123 unsigned char pixel_clock_max; 124 unsigned char gtf_data[8]; 125 } range_data; 126 } data; 127 } __attribute__ ((__packed__)); 128 129 struct edid1_info { 130 unsigned char header[8]; 131 unsigned char manufacturer_name[2]; 132 #define EDID1_INFO_MANUFACTURER_NAME_ZERO(_x) \ 133 GET_BIT(((_x).manufacturer_name[0]), 7) 134 #define EDID1_INFO_MANUFACTURER_NAME_CHAR1(_x) \ 135 GET_BITS(((_x).manufacturer_name[0]), 6, 2) 136 #define EDID1_INFO_MANUFACTURER_NAME_CHAR2(_x) \ 137 ((GET_BITS(((_x).manufacturer_name[0]), 1, 0) << 3) + \ 138 GET_BITS(((_x).manufacturer_name[1]), 7, 5)) 139 #define EDID1_INFO_MANUFACTURER_NAME_CHAR3(_x) \ 140 GET_BITS(((_x).manufacturer_name[1]), 4, 0) 141 unsigned char product_code[2]; 142 #define EDID1_INFO_PRODUCT_CODE(_x) \ 143 (((uint16_t)(_x).product_code[1] << 8) + (_x).product_code[0]) 144 unsigned char serial_number[4]; 145 #define EDID1_INFO_SERIAL_NUMBER(_x) \ 146 (((uint32_t)(_x).serial_number[3] << 24) + \ 147 ((_x).serial_number[2] << 16) + ((_x).serial_number[1] << 8) + \ 148 (_x).serial_number[0]) 149 unsigned char week; 150 unsigned char year; 151 unsigned char version; 152 unsigned char revision; 153 unsigned char video_input_definition; 154 #define EDID1_INFO_VIDEO_INPUT_DIGITAL(_x) \ 155 GET_BIT(((_x).video_input_definition), 7) 156 #define EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(_x) \ 157 GET_BITS(((_x).video_input_definition), 6, 5) 158 #define EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(_x) \ 159 GET_BIT(((_x).video_input_definition), 4) 160 #define EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(_x) \ 161 GET_BIT(((_x).video_input_definition), 3) 162 #define EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(_x) \ 163 GET_BIT(((_x).video_input_definition), 2) 164 #define EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(_x) \ 165 GET_BIT(((_x).video_input_definition), 1) 166 #define EDID1_INFO_VIDEO_INPUT_SERRATION_V(_x) \ 167 GET_BIT(((_x).video_input_definition), 0) 168 unsigned char max_size_horizontal; 169 unsigned char max_size_vertical; 170 unsigned char gamma; 171 unsigned char feature_support; 172 #define EDID1_INFO_FEATURE_STANDBY(_x) \ 173 GET_BIT(((_x).feature_support), 7) 174 #define EDID1_INFO_FEATURE_SUSPEND(_x) \ 175 GET_BIT(((_x).feature_support), 6) 176 #define EDID1_INFO_FEATURE_ACTIVE_OFF(_x) \ 177 GET_BIT(((_x).feature_support), 5) 178 #define EDID1_INFO_FEATURE_DISPLAY_TYPE(_x) \ 179 GET_BITS(((_x).feature_support), 4, 3) 180 #define EDID1_INFO_FEATURE_RGB(_x) \ 181 GET_BIT(((_x).feature_support), 2) 182 #define EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(_x) \ 183 GET_BIT(((_x).feature_support), 1) 184 #define EDID1_INFO_FEATURE_DEFAULT_GTF_SUPPORT(_x) \ 185 GET_BIT(((_x).feature_support), 0) 186 unsigned char color_characteristics[10]; 187 unsigned char established_timings[3]; 188 #define EDID1_INFO_ESTABLISHED_TIMING_720X400_70(_x) \ 189 GET_BIT(((_x).established_timings[0]), 7) 190 #define EDID1_INFO_ESTABLISHED_TIMING_720X400_88(_x) \ 191 GET_BIT(((_x).established_timings[0]), 6) 192 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_60(_x) \ 193 GET_BIT(((_x).established_timings[0]), 5) 194 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_67(_x) \ 195 GET_BIT(((_x).established_timings[0]), 4) 196 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_72(_x) \ 197 GET_BIT(((_x).established_timings[0]), 3) 198 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_75(_x) \ 199 GET_BIT(((_x).established_timings[0]), 2) 200 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_56(_x) \ 201 GET_BIT(((_x).established_timings[0]), 1) 202 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_60(_x) \ 203 GET_BIT(((_x).established_timings[0]), 0) 204 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_72(_x) \ 205 GET_BIT(((_x).established_timings[1]), 7) 206 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_75(_x) \ 207 GET_BIT(((_x).established_timings[1]), 6) 208 #define EDID1_INFO_ESTABLISHED_TIMING_832X624_75(_x) \ 209 GET_BIT(((_x).established_timings[1]), 5) 210 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(_x) \ 211 GET_BIT(((_x).established_timings[1]), 4) 212 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(_x) \ 213 GET_BIT(((_x).established_timings[1]), 3) 214 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(_x) \ 215 GET_BIT(((_x).established_timings[1]), 2) 216 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(_x) \ 217 GET_BIT(((_x).established_timings[1]), 1) 218 #define EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(_x) \ 219 GET_BIT(((_x).established_timings[1]), 0) 220 #define EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(_x) \ 221 GET_BIT(((_x).established_timings[2]), 7) 222 struct { 223 unsigned char xresolution; 224 unsigned char aspect_vfreq; 225 } __attribute__((__packed__)) standard_timings[8]; 226 #define EDID1_INFO_STANDARD_TIMING_XRESOLUTION(_x, _i) \ 227 (((_x).standard_timings[_i]).xresolution) 228 #define EDID1_INFO_STANDARD_TIMING_ASPECT(_x, _i) \ 229 GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 7, 6) 230 #define EDID1_INFO_STANDARD_TIMING_VFREQ(_x, _i) \ 231 GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 5, 0) 232 union { 233 unsigned char timing[72]; 234 struct edid_monitor_descriptor descriptor[4]; 235 } monitor_details; 236 unsigned char extension_flag; 237 unsigned char checksum; 238 } __attribute__ ((__packed__)); 239 240 enum edid_cea861_db_types { 241 EDID_CEA861_DB_AUDIO = 0x01, 242 EDID_CEA861_DB_VIDEO = 0x02, 243 EDID_CEA861_DB_VENDOR = 0x03, 244 EDID_CEA861_DB_SPEAKER = 0x04, 245 }; 246 247 struct edid_cea861_info { 248 unsigned char extension_tag; 249 #define EDID_CEA861_EXTENSION_TAG 0x02 250 unsigned char revision; 251 unsigned char dtd_offset; 252 unsigned char dtd_count; 253 #define EDID_CEA861_SUPPORTS_UNDERSCAN(_x) \ 254 GET_BIT(((_x).dtd_count), 7) 255 #define EDID_CEA861_SUPPORTS_BASIC_AUDIO(_x) \ 256 GET_BIT(((_x).dtd_count), 6) 257 #define EDID_CEA861_SUPPORTS_YUV444(_x) \ 258 GET_BIT(((_x).dtd_count), 5) 259 #define EDID_CEA861_SUPPORTS_YUV422(_x) \ 260 GET_BIT(((_x).dtd_count), 4) 261 #define EDID_CEA861_DTD_COUNT(_x) \ 262 GET_BITS(((_x).dtd_count), 3, 0) 263 unsigned char data[124]; 264 #define EDID_CEA861_DB_TYPE(_x, offset) \ 265 GET_BITS((_x).data[offset], 7, 5) 266 #define EDID_CEA861_DB_LEN(_x, offset) \ 267 GET_BITS((_x).data[offset], 4, 0) 268 } __attribute__ ((__packed__)); 269 270 /** 271 * Print the EDID info. 272 * 273 * @param edid_info The EDID info to be printed 274 */ 275 void edid_print_info(struct edid1_info *edid_info); 276 277 /** 278 * Check the EDID info. 279 * 280 * @param info The EDID info to be checked 281 * @return 0 on valid, or -1 on invalid 282 */ 283 int edid_check_info(struct edid1_info *info); 284 285 /** 286 * Check checksum of a 128 bytes EDID data block 287 * 288 * @param edid_block EDID block data 289 * 290 * @return 0 on success, or a negative errno on error 291 */ 292 int edid_check_checksum(u8 *edid_block); 293 294 /** 295 * Get the horizontal and vertical rate ranges of the monitor. 296 * 297 * @param edid The EDID info 298 * @param hmin Returns the minimum horizontal rate 299 * @param hmax Returns the maxium horizontal rate 300 * @param vmin Returns the minimum vertical rate 301 * @param vmax Returns the maxium vertical rate 302 * @return 0 on success, or -1 on error 303 */ 304 int edid_get_ranges(struct edid1_info *edid, unsigned int *hmin, 305 unsigned int *hmax, unsigned int *vmin, 306 unsigned int *vmax); 307 308 struct display_timing; 309 310 /** 311 * edid_get_timing() - Get basic digital display parameters 312 * 313 * @param buf Buffer containing EDID data 314 * @param buf_size Size of buffer in bytes 315 * @param timing Place to put preferring timing information 316 * @param panel_bits_per_colourp Place to put the number of bits per 317 * colour supported by the panel. This will be set to 318 * -1 if not available 319 * @return 0 if timings are OK, -ve on error 320 */ 321 int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing, 322 int *panel_bits_per_colourp); 323 324 #endif /* __EDID_H_ */ 325