2 * Copyright (c) 2012 The Chromium OS Authors.
5 * Petr Stetiar <ynezz@true.cz>
7 * SPDX-License-Identifier: GPL-2.0+
9 * Contains stolen code from ddcprobe project which is:
10 * Copyright (C) Nalin Dahyabhai <bigfun@pobox.com>
15 #include <linux/ctype.h>
16 #include <linux/string.h>
18 int edid_check_info(struct edid1_info
*edid_info
)
20 if ((edid_info
== NULL
) || (edid_info
->version
== 0))
23 if (memcmp(edid_info
->header
, "\x0\xff\xff\xff\xff\xff\xff\x0", 8))
26 if (edid_info
->version
== 0xff && edid_info
->revision
== 0xff)
32 int edid_get_ranges(struct edid1_info
*edid
, unsigned int *hmin
,
33 unsigned int *hmax
, unsigned int *vmin
,
37 struct edid_monitor_descriptor
*monitor
;
39 *hmin
= *hmax
= *vmin
= *vmax
= 0;
40 if (edid_check_info(edid
))
43 for (i
= 0; i
< ARRAY_SIZE(edid
->monitor_details
.descriptor
); i
++) {
44 monitor
= &edid
->monitor_details
.descriptor
[i
];
45 if (monitor
->type
== EDID_MONITOR_DESCRIPTOR_RANGE
) {
46 *hmin
= monitor
->data
.range_data
.horizontal_min
;
47 *hmax
= monitor
->data
.range_data
.horizontal_max
;
48 *vmin
= monitor
->data
.range_data
.vertical_min
;
49 *vmax
= monitor
->data
.range_data
.vertical_max
;
57 * Snip the tailing whitespace/return of a string.
59 * @param string The string to be snipped
60 * @return the snipped string
62 static char *snip(char *string
)
67 * This is always a 13 character buffer
68 * and it's not always terminated.
71 s
= &string
[strlen(string
) - 1];
73 while (s
>= string
&& (isspace(*s
) || *s
== '\n' || *s
== '\r' ||
81 * Print an EDID monitor descriptor block
83 * @param monitor The EDID monitor descriptor block
84 * @have_timing Modifies to 1 if the desciptor contains timing info
86 static void edid_print_dtd(struct edid_monitor_descriptor
*monitor
,
87 unsigned int *have_timing
)
89 unsigned char *bytes
= (unsigned char *)monitor
;
90 struct edid_detailed_timing
*timing
=
91 (struct edid_detailed_timing
*)monitor
;
93 if (bytes
[0] == 0 && bytes
[1] == 0) {
94 if (monitor
->type
== EDID_MONITOR_DESCRIPTOR_SERIAL
)
95 printf("Monitor serial number: %s\n",
96 snip(monitor
->data
.string
));
97 else if (monitor
->type
== EDID_MONITOR_DESCRIPTOR_ASCII
)
98 printf("Monitor ID: %s\n",
99 snip(monitor
->data
.string
));
100 else if (monitor
->type
== EDID_MONITOR_DESCRIPTOR_NAME
)
101 printf("Monitor name: %s\n",
102 snip(monitor
->data
.string
));
103 else if (monitor
->type
== EDID_MONITOR_DESCRIPTOR_RANGE
)
104 printf("Monitor range limits, horizontal sync: "
105 "%d-%d kHz, vertical refresh: "
106 "%d-%d Hz, max pixel clock: "
108 monitor
->data
.range_data
.horizontal_min
,
109 monitor
->data
.range_data
.horizontal_max
,
110 monitor
->data
.range_data
.vertical_min
,
111 monitor
->data
.range_data
.vertical_max
,
112 monitor
->data
.range_data
.pixel_clock_max
* 10);
114 uint32_t pixclock
, h_active
, h_blanking
, v_active
, v_blanking
;
115 uint32_t h_total
, v_total
, vfreq
;
117 pixclock
= EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing
);
118 h_active
= EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing
);
119 h_blanking
= EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing
);
120 v_active
= EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing
);
121 v_blanking
= EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing
);
123 h_total
= h_active
+ h_blanking
;
124 v_total
= v_active
+ v_blanking
;
125 if (v_total
* h_total
)
126 vfreq
= pixclock
/ (v_total
* h_total
);
128 vfreq
= 1; /* Error case */
129 printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active
,
130 v_active
, h_active
> 1000 ? ' ' : '\t', vfreq
);
136 * Get the manufacturer name from an EDID info.
138 * @param edid_info The EDID info to be printed
139 * @param name Returns the string of the manufacturer name
141 static void edid_get_manufacturer_name(struct edid1_info
*edid
, char *name
)
143 name
[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid
) + 'A' - 1;
144 name
[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid
) + 'A' - 1;
145 name
[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid
) + 'A' - 1;
149 void edid_print_info(struct edid1_info
*edid_info
)
152 char manufacturer
[4];
153 unsigned int have_timing
= 0;
154 uint32_t serial_number
;
156 if (edid_check_info(edid_info
)) {
157 printf("Not a valid EDID\n");
161 printf("EDID version: %d.%d\n",
162 edid_info
->version
, edid_info
->revision
);
164 printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info
));
166 edid_get_manufacturer_name(edid_info
, manufacturer
);
167 printf("Manufacturer: %s\n", manufacturer
);
169 serial_number
= EDID1_INFO_SERIAL_NUMBER(*edid_info
);
170 if (serial_number
!= 0xffffffff) {
171 if (strcmp(manufacturer
, "MAG") == 0)
172 serial_number
-= 0x7000000;
173 if (strcmp(manufacturer
, "OQI") == 0)
174 serial_number
-= 456150000;
175 if (strcmp(manufacturer
, "VSC") == 0)
176 serial_number
-= 640000000;
178 printf("Serial number: %08x\n", serial_number
);
179 printf("Manufactured in week: %d year: %d\n",
180 edid_info
->week
, edid_info
->year
+ 1990);
182 printf("Video input definition: %svoltage level %d%s%s%s%s%s\n",
183 EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info
) ?
184 "digital signal, " : "analog signal, ",
185 EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info
),
186 EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info
) ?
187 ", blank to black" : "",
188 EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info
) ?
189 ", separate sync" : "",
190 EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info
) ?
191 ", composite sync" : "",
192 EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info
) ?
193 ", sync on green" : "",
194 EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info
) ?
195 ", serration v" : "");
197 printf("Monitor is %s\n",
198 EDID1_INFO_FEATURE_RGB(*edid_info
) ? "RGB" : "non-RGB");
200 printf("Maximum visible display size: %d cm x %d cm\n",
201 edid_info
->max_size_horizontal
,
202 edid_info
->max_size_vertical
);
204 printf("Power management features: %s%s, %s%s, %s%s\n",
205 EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info
) ?
206 "" : "no ", "active off",
207 EDID1_INFO_FEATURE_SUSPEND(*edid_info
) ? "" : "no ", "suspend",
208 EDID1_INFO_FEATURE_STANDBY(*edid_info
) ? "" : "no ", "standby");
210 printf("Estabilished timings:\n");
211 if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info
))
212 printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n");
213 if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info
))
214 printf("\t720x400\t\t88 Hz (XGA2)\n");
215 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info
))
216 printf("\t640x480\t\t60 Hz (VGA)\n");
217 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info
))
218 printf("\t640x480\t\t67 Hz (Mac II, Apple)\n");
219 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info
))
220 printf("\t640x480\t\t72 Hz (VESA)\n");
221 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info
))
222 printf("\t640x480\t\t75 Hz (VESA)\n");
223 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info
))
224 printf("\t800x600\t\t56 Hz (VESA)\n");
225 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info
))
226 printf("\t800x600\t\t60 Hz (VESA)\n");
227 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info
))
228 printf("\t800x600\t\t72 Hz (VESA)\n");
229 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info
))
230 printf("\t800x600\t\t75 Hz (VESA)\n");
231 if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info
))
232 printf("\t832x624\t\t75 Hz (Mac II)\n");
233 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info
))
234 printf("\t1024x768\t87 Hz Interlaced (8514A)\n");
235 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info
))
236 printf("\t1024x768\t60 Hz (VESA)\n");
237 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info
))
238 printf("\t1024x768\t70 Hz (VESA)\n");
239 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info
))
240 printf("\t1024x768\t75 Hz (VESA)\n");
241 if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info
))
242 printf("\t1280x1024\t75 (VESA)\n");
243 if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info
))
244 printf("\t1152x870\t75 (Mac II)\n");
246 /* Standard timings. */
247 printf("Standard timings:\n");
248 for (i
= 0; i
< ARRAY_SIZE(edid_info
->standard_timings
); i
++) {
249 unsigned int aspect
= 10000;
251 unsigned char xres
, vfreq
;
253 xres
= EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info
, i
);
254 vfreq
= EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info
, i
);
255 if ((xres
!= vfreq
) ||
256 ((xres
!= 0) && (xres
!= 1)) ||
257 ((vfreq
!= 0) && (vfreq
!= 1))) {
258 switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info
,
274 y
= x
* aspect
/ 10000;
275 printf("\t%dx%d%c\t%d Hz\n", x
, y
,
276 x
> 1000 ? ' ' : '\t', (vfreq
& 0x3f) + 60);
281 /* Detailed timing information. */
282 for (i
= 0; i
< ARRAY_SIZE(edid_info
->monitor_details
.descriptor
);
284 edid_print_dtd(&edid_info
->monitor_details
.descriptor
[i
],