2 * Copyright (c) 2012 The Chromium OS Authors.
5 * Petr Stetiar <ynezz@true.cz>
7 * See file CREDITS for list of people who contributed to this
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation; either version 2 of
13 * the License, or (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
25 * Contains stolen code from ddcprobe project which is:
26 * Copyright (C) Nalin Dahyabhai <bigfun@pobox.com>
33 #include <linux/types.h>
35 #define GET_BIT(_x, _pos) \
36 (((_x) >> (_pos)) & 1)
37 #define GET_BITS(_x, _pos_msb, _pos_lsb) \
38 (((_x) >> (_pos_lsb)) & ((1 << ((_pos_msb) - (_pos_lsb) + 1)) - 1))
40 /* Aspect ratios used in EDID info. */
48 /* Detailed timing information used in EDID v1.x */
49 struct edid_detailed_timing {
50 unsigned char pixel_clock[2];
51 #define EDID_DETAILED_TIMING_PIXEL_CLOCK(_x) \
52 (((((uint32_t)(_x).pixel_clock[1]) << 8) + \
53 (_x).pixel_clock[0]) * 10000)
54 unsigned char horizontal_active;
55 unsigned char horizontal_blanking;
56 unsigned char horizontal_active_blanking_hi;
57 #define EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(_x) \
58 ((GET_BITS((_x).horizontal_active_blanking_hi, 7, 4) << 8) + \
59 (_x).horizontal_active)
60 #define EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(_x) \
61 ((GET_BITS((_x).horizontal_active_blanking_hi, 3, 0) << 8) + \
62 (_x).horizontal_blanking)
63 unsigned char vertical_active;
64 unsigned char vertical_blanking;
65 unsigned char vertical_active_blanking_hi;
66 #define EDID_DETAILED_TIMING_VERTICAL_ACTIVE(_x) \
67 ((GET_BITS((_x).vertical_active_blanking_hi, 7, 4) << 8) + \
69 #define EDID_DETAILED_TIMING_VERTICAL_BLANKING(_x) \
70 ((GET_BITS((_x).vertical_active_blanking_hi, 3, 0) << 8) + \
71 (_x).vertical_blanking)
72 unsigned char hsync_offset;
73 unsigned char hsync_pulse_width;
74 unsigned char sync_offset_pulse_width;
75 unsigned char hsync_vsync_offset_pulse_width_hi;
76 #define EDID_DETAILED_TIMING_HSYNC_OFFSET(_x) \
77 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 7, 6) << 8) + \
79 #define EDID_DETAILED_TIMING_HSYNC_PULSE_WIDTH(_x) \
80 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 5, 4) << 8) + \
81 (_x).hsync_pulse_width)
82 #define EDID_DETAILED_TIMING_VSYNC_OFFSET(_x) \
83 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 3, 2) << 4) + \
84 GET_BITS((_x).vsync_offset_pulse_width, 7, 4))
85 #define EDID_DETAILED_TIMING_VSYNC_PULSE_WIDTH(_x) \
86 ((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 1, 0) << 4) + \
87 GET_BITS((_x).vsync_offset_pulse_width, 3, 0))
88 unsigned char himage_size;
89 unsigned char vimage_size;
90 unsigned char himage_vimage_size_hi;
91 #define EDID_DETAILED_TIMING_HIMAGE_SIZE(_x) \
92 ((GET_BITS((_x).himage_vimage_size_hi, 7, 4) << 8) + (_x).himage_size)
93 #define EDID_DETAILED_TIMING_VIMAGE_SIZE(_x) \
94 ((GET_BITS((_x).himage_vimage_size_hi, 3, 0) << 8) + (_x).vimage_size)
95 unsigned char hborder;
96 unsigned char vborder;
98 #define EDID_DETAILED_TIMING_FLAG_INTERLACED(_x) \
99 GET_BIT((_x).flags, 7)
100 #define EDID_DETAILED_TIMING_FLAG_STEREO(_x) \
101 GET_BITS((_x).flags, 6, 5)
102 #define EDID_DETAILED_TIMING_FLAG_DIGITAL_COMPOSITE(_x) \
103 GET_BITS((_x).flags, 4, 3)
104 #define EDID_DETAILED_TIMING_FLAG_POLARITY(_x) \
105 GET_BITS((_x).flags, 2, 1)
106 #define EDID_DETAILED_TIMING_FLAG_INTERLEAVED(_x) \
107 GET_BIT((_x).flags, 0)
108 } __attribute__ ((__packed__));
110 enum edid_monitor_descriptor_types {
111 EDID_MONITOR_DESCRIPTOR_SERIAL = 0xff,
112 EDID_MONITOR_DESCRIPTOR_ASCII = 0xfe,
113 EDID_MONITOR_DESCRIPTOR_RANGE = 0xfd,
114 EDID_MONITOR_DESCRIPTOR_NAME = 0xfc,
117 struct edid_monitor_descriptor {
118 uint16_t zero_flag_1;
119 unsigned char zero_flag_2;
121 unsigned char zero_flag_3;
125 unsigned char vertical_min;
126 unsigned char vertical_max;
127 unsigned char horizontal_min;
128 unsigned char horizontal_max;
129 unsigned char pixel_clock_max;
130 unsigned char gtf_data[8];
133 } __attribute__ ((__packed__));
136 unsigned char header[8];
137 unsigned char manufacturer_name[2];
138 #define EDID1_INFO_MANUFACTURER_NAME_ZERO(_x) \
139 GET_BIT(((_x).manufacturer_name[0]), 7)
140 #define EDID1_INFO_MANUFACTURER_NAME_CHAR1(_x) \
141 GET_BITS(((_x).manufacturer_name[0]), 6, 2)
142 #define EDID1_INFO_MANUFACTURER_NAME_CHAR2(_x) \
143 ((GET_BITS(((_x).manufacturer_name[0]), 1, 0) << 3) + \
144 GET_BITS(((_x).manufacturer_name[1]), 7, 5))
145 #define EDID1_INFO_MANUFACTURER_NAME_CHAR3(_x) \
146 GET_BITS(((_x).manufacturer_name[1]), 4, 0)
147 unsigned char product_code[2];
148 #define EDID1_INFO_PRODUCT_CODE(_x) \
149 (((uint16_t)(_x).product_code[1] << 8) + (_x).product_code[0])
150 unsigned char serial_number[4];
151 #define EDID1_INFO_SERIAL_NUMBER(_x) \
152 (((uint32_t)(_x).serial_number[3] << 24) + \
153 ((_x).serial_number[2] << 16) + ((_x).serial_number[1] << 8) + \
154 (_x).serial_number[0])
157 unsigned char version;
158 unsigned char revision;
159 unsigned char video_input_definition;
160 #define EDID1_INFO_VIDEO_INPUT_DIGITAL(_x) \
161 GET_BIT(((_x).video_input_definition), 7)
162 #define EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(_x) \
163 GET_BITS(((_x).video_input_definition), 6, 5)
164 #define EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(_x) \
165 GET_BIT(((_x).video_input_definition), 4)
166 #define EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(_x) \
167 GET_BIT(((_x).video_input_definition), 3)
168 #define EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(_x) \
169 GET_BIT(((_x).video_input_definition), 2)
170 #define EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(_x) \
171 GET_BIT(((_x).video_input_definition), 1)
172 #define EDID1_INFO_VIDEO_INPUT_SERRATION_V(_x) \
173 GET_BIT(((_x).video_input_definition), 0)
174 unsigned char max_size_horizontal;
175 unsigned char max_size_vertical;
177 unsigned char feature_support;
178 #define EDID1_INFO_FEATURE_STANDBY(_x) \
179 GET_BIT(((_x).feature_support), 7)
180 #define EDID1_INFO_FEATURE_SUSPEND(_x) \
181 GET_BIT(((_x).feature_support), 6)
182 #define EDID1_INFO_FEATURE_ACTIVE_OFF(_x) \
183 GET_BIT(((_x).feature_support), 5)
184 #define EDID1_INFO_FEATURE_DISPLAY_TYPE(_x) \
185 GET_BITS(((_x).feature_support), 4, 3)
186 #define EDID1_INFO_FEATURE_RGB(_x) \
187 GET_BIT(((_x).feature_support), 2)
188 #define EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(_x) \
189 GET_BIT(((_x).feature_support), 1)
190 #define EDID1_INFO_FEATURE_DEFAULT_GTF_SUPPORT(_x) \
191 GET_BIT(((_x).feature_support), 0)
192 unsigned char color_characteristics[10];
193 unsigned char established_timings[3];
194 #define EDID1_INFO_ESTABLISHED_TIMING_720X400_70(_x) \
195 GET_BIT(((_x).established_timings[0]), 7)
196 #define EDID1_INFO_ESTABLISHED_TIMING_720X400_88(_x) \
197 GET_BIT(((_x).established_timings[0]), 6)
198 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_60(_x) \
199 GET_BIT(((_x).established_timings[0]), 5)
200 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_67(_x) \
201 GET_BIT(((_x).established_timings[0]), 4)
202 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_72(_x) \
203 GET_BIT(((_x).established_timings[0]), 3)
204 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_75(_x) \
205 GET_BIT(((_x).established_timings[0]), 2)
206 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_56(_x) \
207 GET_BIT(((_x).established_timings[0]), 1)
208 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_60(_x) \
209 GET_BIT(((_x).established_timings[0]), 0)
210 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_72(_x) \
211 GET_BIT(((_x).established_timings[1]), 7)
212 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_75(_x) \
213 GET_BIT(((_x).established_timings[1]), 6)
214 #define EDID1_INFO_ESTABLISHED_TIMING_832X624_75(_x) \
215 GET_BIT(((_x).established_timings[1]), 5)
216 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(_x) \
217 GET_BIT(((_x).established_timings[1]), 4)
218 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(_x) \
219 GET_BIT(((_x).established_timings[1]), 3)
220 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(_x) \
221 GET_BIT(((_x).established_timings[1]), 2)
222 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(_x) \
223 GET_BIT(((_x).established_timings[1]), 1)
224 #define EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(_x) \
225 GET_BIT(((_x).established_timings[1]), 0)
226 #define EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(_x) \
227 GET_BIT(((_x).established_timings[2]), 7)
229 unsigned char xresolution;
230 unsigned char aspect_vfreq;
231 } __attribute__((__packed__)) standard_timings[8];
232 #define EDID1_INFO_STANDARD_TIMING_XRESOLUTION(_x, _i) \
233 (((_x).standard_timings[_i]).xresolution)
234 #define EDID1_INFO_STANDARD_TIMING_ASPECT(_x, _i) \
235 GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 7, 6)
236 #define EDID1_INFO_STANDARD_TIMING_VFREQ(_x, _i) \
237 GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 5, 0)
239 unsigned char timing[72];
240 struct edid_monitor_descriptor descriptor[4];
242 unsigned char extension_flag;
243 unsigned char checksum;
244 } __attribute__ ((__packed__));
247 * Print the EDID info.
249 * @param edid_info The EDID info to be printed
251 void edid_print_info(struct edid1_info *edid_info);
254 * Check the EDID info.
256 * @param info The EDID info to be checked
257 * @return 0 on valid, or -1 on invalid
259 int edid_check_info(struct edid1_info *info);
262 * Get the horizontal and vertical rate ranges of the monitor.
264 * @param edid The EDID info
265 * @param hmin Returns the minimum horizontal rate
266 * @param hmax Returns the maxium horizontal rate
267 * @param vmin Returns the minimum vertical rate
268 * @param vmax Returns the maxium vertical rate
269 * @return 0 on success, or -1 on error
271 int edid_get_ranges(struct edid1_info *edid, unsigned int *hmin,
272 unsigned int *hmax, unsigned int *vmin,
275 #endif /* __EDID_H_ */