include/edid.h

   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_ */