/*

* Copyright 2007 Red Hat, Inc.

*

* Permission is hereby granted, free of charge, to any person obtaining a

* copy of this software and associated documentation files (the "Software"),

* to deal in the Software without restriction, including without limitation

* on the rights to use, copy, modify, merge, publish, distribute, sub

* license, and/or sell copies of the Software, and to permit persons to whom

* the Software is furnished to do so, subject to the following conditions:

*

* The above copyright notice and this permission notice (including the next

* paragraph) shall be included in all copies or substantial portions of the

* Software.

*

* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL

* THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER

* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN

* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

*/

/* Author: Soren Sandmann <sandmann@redhat.com> */

#include "edid.h"

#include <stdlib.h>

#include <string.h>

#include <math.h>

#include <stdio.h>

#define TRUE 1

#define FALSE 0

static int

get_bit (int in, int bit)

{

return (in & (1 << bit)) >> bit;

}

static int

get_bits (int in, int begin, int end)

{

int mask = (1 << (end - begin + 1)) - 1;

return (in >> begin) & mask;

}

static int

decode_header (const uchar *edid)

{

if (memcmp (edid, "\x00\xff\xff\xff\xff\xff\xff\x00", 8) == 0)

return TRUE;

return FALSE;

}

static int

decode_vendor_and_product_identification (const uchar *edid, MonitorInfo *info)

{

int is_model_year;

/* Manufacturer Code */

info->manufacturer_code[0] = get_bits (edid[0x08], 2, 6);

info->manufacturer_code[1] = get_bits (edid[0x08], 0, 1) << 3;

info->manufacturer_code[1] |= get_bits (edid[0x09], 5, 7);

info->manufacturer_code[2] = get_bits (edid[0x09], 0, 4);

info->manufacturer_code[3] = '\0';

info->manufacturer_code[0] += 'A' - 1;

info->manufacturer_code[1] += 'A' - 1;

info->manufacturer_code[2] += 'A' - 1;

/* Product Code */

info->product_code = edid[0x0b] << 8 | edid[0x0a];

/* Serial Number */

info->serial_number =

edid[0x0c] | edid[0x0d] << 8 | edid[0x0e] << 16 | edid[0x0f] << 24;

/* Week and Year */

is_model_year = FALSE;

switch (edid[0x10])

{

case 0x00:

info->production_week = -1;

break;

case 0xff:

info->production_week = -1;

is_model_year = TRUE;

break;

default:

info->production_week = edid[0x10];

break;

}

if (is_model_year)

{

info->production_year = -1;

info->model_year = 1990 + edid[0x11];

}

else

{

info->production_year = 1990 + edid[0x11];

info->model_year = -1;

}

return TRUE;

}

static int

decode_edid_version (const uchar *edid, MonitorInfo *info)

{

info->major_version = edid[0x12];

info->minor_version = edid[0x13];

return TRUE;

}

static int

decode_display_parameters (const uchar *edid, MonitorInfo *info)

{

/* Digital vs Analog */

info->is_digital = get_bit (edid[0x14], 7);

if (info->is_digital)

{

int bits;

static const int bit_depth[8] =

{

-1, 6, 8, 10, 12, 14, 16, -1

};

static const Interface interfaces[6] =

{

UNDEFINED, DVI, HDMI_A, HDMI_B, MDDI, DISPLAY_PORT

};

bits = get_bits (edid[0x14], 4, 6);

info->digital.bits_per_primary = bit_depth[bits];

bits = get_bits (edid[0x14], 0, 3);

if (bits <= 5)

info->digital.interface = interfaces[bits];

else

info->digital.interface = UNDEFINED;

}

else

{

int bits = get_bits (edid[0x14], 5, 6);

static const double levels[][3] =

{

{ 0.7, 0.3, 1.0 },

{ 0.714, 0.286, 1.0 },

{ 1.0, 0.4, 1.4 },

{ 0.7, 0.0, 0.7 },

};

info->analog.video_signal_level = levels[bits][0];

info->analog.sync_signal_level = levels[bits][1];

info->analog.total_signal_level = levels[bits][2];

info->analog.blank_to_black = get_bit (edid[0x14], 4);

info->analog.separate_hv_sync = get_bit (edid[0x14], 3);

info->analog.composite_sync_on_h = get_bit (edid[0x14], 2);

info->analog.composite_sync_on_green = get_bit (edid[0x14], 1);

info->analog.serration_on_vsync = get_bit (edid[0x14], 0);

}

/* Screen Size / Aspect Ratio */

if (edid[0x15] == 0 && edid[0x16] == 0)

{

info->width_mm = -1;

info->height_mm = -1;

info->aspect_ratio = -1.0;

}

else if (edid[0x16] == 0)

{

info->width_mm = -1;

info->height_mm = -1;

info->aspect_ratio = 100.0 / (edid[0x15] + 99);

}

else if (edid[0x15] == 0)

{

info->width_mm = -1;

info->height_mm = -1;

info->aspect_ratio = 100.0 / (edid[0x16] + 99);

info->aspect_ratio = 1/info->aspect_ratio; /* portrait */

}

else

{

info->width_mm = 10 * edid[0x15];

info->height_mm = 10 * edid[0x16];

}

/* Gamma */

if (edid[0x17] == 0xFF)

info->gamma = -1.0;

else

info->gamma = (edid[0x17] + 100.0) / 100.0;

/* Features */

info->standby = get_bit (edid[0x18], 7);

info->suspend = get_bit (edid[0x18], 6);

info->active_off = get_bit (edid[0x18], 5);

if (info->is_digital)

{

info->digital.rgb444 = TRUE;

if (get_bit (edid[0x18], 3))

info->digital.ycrcb444 = 1;

if (get_bit (edid[0x18], 4))

info->digital.ycrcb422 = 1;

}

else

{

int bits = get_bits (edid[0x18], 3, 4);

ColorType color_type[4] =

{

MONOCHROME, RGB, OTHER_COLOR, UNDEFINED_COLOR

};

info->analog.color_type = color_type[bits];

}

info->srgb_is_standard = get_bit (edid[0x18], 2);

/* In 1.3 this is called "has preferred timing" */

info->preferred_timing_includes_native = get_bit (edid[0x18], 1);

/* FIXME: In 1.3 this indicates whether the monitor accepts GTF */

info->continuous_frequency = get_bit (edid[0x18], 0);

return TRUE;

}

static double

decode_fraction (int high, int low)

{

double result = 0.0;

int i;

high = (high << 2) | low;

for (i = 0; i < 10; ++i)

result += get_bit (high, i) * pow (2, i - 10);

return result;

}

static int

decode_color_characteristics (const uchar *edid, MonitorInfo *info)

{

info->red_x = decode_fraction (edid[0x1b], get_bits (edid[0x19], 6, 7));

info->red_y = decode_fraction (edid[0x1c], get_bits (edid[0x19], 5, 4));

info->green_x = decode_fraction (edid[0x1d], get_bits (edid[0x19], 2, 3));

info->green_y = decode_fraction (edid[0x1e], get_bits (edid[0x19], 0, 1));

info->blue_x = decode_fraction (edid[0x1f], get_bits (edid[0x1a], 6, 7));

info->blue_y = decode_fraction (edid[0x20], get_bits (edid[0x1a], 4, 5));

info->white_x = decode_fraction (edid[0x21], get_bits (edid[0x1a], 2, 3));

info->white_y = decode_fraction (edid[0x22], get_bits (edid[0x1a], 0, 1));

return TRUE;

}

static int

decode_established_timings (const uchar *edid, MonitorInfo *info)

{

static const Timing established[][8] =

{

{

{ 800, 600, 60 },

{ 800, 600, 56 },

{ 640, 480, 75 },

{ 640, 480, 72 },

{ 640, 480, 67 },

{ 640, 480, 60 },

{ 720, 400, 88 },

{ 720, 400, 70 }

},

{

{ 1280, 1024, 75 },

{ 1024, 768, 75 },

{ 1024, 768, 70 },

{ 1024, 768, 60 },

{ 1024, 768, 87 },

{ 832, 624, 75 },

{ 800, 600, 75 },

{ 800, 600, 72 }

},

{

{ 0, 0, 0 },

{ 0, 0, 0 },

{ 0, 0, 0 },

{ 0, 0, 0 },

{ 0, 0, 0 },

{ 0, 0, 0 },

{ 0, 0, 0 },

{ 1152, 870, 75 }

},

};

int i, j, idx;

idx = 0;

for (i = 0; i < 3; ++i)

{

for (j = 0; j < 8; ++j)

{

int byte = edid[0x23 + i];

if (get_bit (byte, j) && established[i][j].frequency != 0)

info->established[idx++] = established[i][j];

}

}

return TRUE;

}

static int

decode_standard_timings (const uchar *edid, MonitorInfo *info)

{

int i;

for (i = 0; i < 8; i++)

{

int first = edid[0x26 + 2 * i];

int second = edid[0x27 + 2 * i];

if (first != 0x01 && second != 0x01)

{

int w = 8 * (first + 31);

int h = 0;

switch (get_bits (second, 6, 7))

{

case 0x00: h = (w / 16) * 10; break;

case 0x01: h = (w / 4) * 3; break;

case 0x02: h = (w / 5) * 4; break;

case 0x03: h = (w / 16) * 9; break;

}

info->standard[i].width = w;

info->standard[i].height = h;

info->standard[i].frequency = get_bits (second, 0, 5) + 60;

}

}

return TRUE;

}

static void

decode_lf_string (const uchar *s, int n_chars, char *result)

{

int i;

for (i = 0; i < n_chars; ++i)

{

if (s[i] == 0x0a)

{

*result++ = '\0';

break;

}

else if (s[i] == 0x00)

{

/* Convert embedded 0's to spaces */

*result++ = ' ';

}

else

{

*result++ = s[i];

}

}

}

static void

decode_display_descriptor (const uchar *desc,

MonitorInfo *info)

{

switch (desc[0x03])

{

case 0xFC:

decode_lf_string (desc + 5, 13, info->dsc_product_name);

break;

case 0xFF:

decode_lf_string (desc + 5, 13, info->dsc_serial_number);

break;

case 0xFE:

decode_lf_string (desc + 5, 13, info->dsc_string);

break;

case 0xFD:

/* Range Limits */

break;

case 0xFB:

/* Color Point */

break;

case 0xFA:

/* Timing Identifications */

break;

case 0xF9:

/* Color Management */

break;

case 0xF8:

/* Timing Codes */

break;

case 0xF7:

/* Established Timings */

break;

case 0x10:

break;

}

}

static void

decode_detailed_timing (const uchar *timing,

DetailedTiming *detailed)

{

int bits;

StereoType stereo[] =

{

NO_STEREO, NO_STEREO, FIELD_RIGHT, FIELD_LEFT,

TWO_WAY_RIGHT_ON_EVEN, TWO_WAY_LEFT_ON_EVEN,

FOUR_WAY_INTERLEAVED, SIDE_BY_SIDE

};

detailed->pixel_clock = (timing[0x00] | timing[0x01] << 8) * 10000;

detailed->h_addr = timing[0x02] | ((timing[0x04] & 0xf0) << 4);

detailed->h_blank = timing[0x03] | ((timing[0x04] & 0x0f) << 8);

detailed->v_addr = timing[0x05] | ((timing[0x07] & 0xf0) << 4);

detailed->v_blank = timing[0x06] | ((timing[0x07] & 0x0f) << 8);

detailed->h_front_porch = timing[0x08] | get_bits (timing[0x0b], 6, 7) << 8;

detailed->h_sync = timing[0x09] | get_bits (timing[0x0b], 4, 5) << 8;

detailed->v_front_porch =

get_bits (timing[0x0a], 4, 7) | get_bits (timing[0x0b], 2, 3) << 4;

detailed->v_sync =

get_bits (timing[0x0a], 0, 3) | get_bits (timing[0x0b], 0, 1) << 4;

detailed->width_mm = timing[0x0c] | get_bits (timing[0x0e], 4, 7) << 8;

detailed->height_mm = timing[0x0d] | get_bits (timing[0x0e], 0, 3) << 8;

detailed->right_border = timing[0x0f];

detailed->top_border = timing[0x10];

detailed->interlaced = get_bit (timing[0x11], 7);

/* Stereo */

bits = get_bits (timing[0x11], 5, 6) << 1 | get_bit (timing[0x11], 0);

detailed->stereo = stereo[bits];

/* Sync */

bits = timing[0x11];

detailed->digital_sync = get_bit (bits, 4);

if (detailed->digital_sync)

{

detailed->digital.composite = !get_bit (bits, 3);

if (detailed->digital.composite)

{

detailed->digital.serrations = get_bit (bits, 2);

detailed->digital.negative_vsync = FALSE;

}

else

{

detailed->digital.serrations = FALSE;

detailed->digital.negative_vsync = !get_bit (bits, 2);

}

detailed->digital.negative_hsync = !get_bit (bits, 0);

}

else

{

detailed->analog.bipolar = get_bit (bits, 3);

detailed->analog.serrations = get_bit (bits, 2);

detailed->analog.sync_on_green = !get_bit (bits, 1);

}

}

static int

decode_descriptors (const uchar *edid, MonitorInfo *info)

{

int i;

int timing_idx;

timing_idx = 0;

for (i = 0; i < 4; ++i)

{

int index = 0x36 + i * 18;

if (edid[index + 0] == 0x00 && edid[index + 1] == 0x00)

{

decode_display_descriptor (edid + index, info);

}

else

{

decode_detailed_timing (

edid + index, &(info->detailed_timings[timing_idx++]));

}

}

info->n_detailed_timings = timing_idx;

return TRUE;

}

static void

decode_check_sum (const uchar *edid,

MonitorInfo *info)

{

int i;

uchar check = 0;

for (i = 0; i < 128; ++i)

check += edid[i];

info->checksum = check;

}

MonitorInfo *

decode_edid (const uchar *edid)

{

MonitorInfo *info = calloc (1, sizeof (MonitorInfo));

decode_check_sum (edid, info);

if (!decode_header (edid) ||

!decode_vendor_and_product_identification (edid, info) ||

!decode_edid_version (edid, info) ||

!decode_display_parameters (edid, info) ||

!decode_color_characteristics (edid, info) ||

!decode_established_timings (edid, info) ||

!decode_standard_timings (edid, info) ||

!decode_descriptors (edid, info)) {

free(info);

return NULL;

}

return info;

}

static const char *

yesno (int v)

{

return v? "yes" : "no";

}

void

dump_monitor_info (MonitorInfo *info)

{

int i;

printf ("Checksum: %d (%s)\n",

info->checksum, info->checksum? "incorrect" : "correct");

printf ("Manufacturer Code: %s\n", info->manufacturer_code);

printf ("Product Code: 0x%x\n", info->product_code);

printf ("Serial Number: %u\n", info->serial_number);

if (info->production_week != -1)

printf ("Production Week: %d\n", info->production_week);

else

printf ("Production Week: unspecified\n");

if (info->production_year != -1)

printf ("Production Year: %d\n", info->production_year);

else

printf ("Production Year: unspecified\n");

if (info->model_year != -1)

printf ("Model Year: %d\n", info->model_year);

else

printf ("Model Year: unspecified\n");

printf ("EDID revision: %d.%d\n", info->major_version, info->minor_version);

printf ("Display is %s\n", info->is_digital? "digital" : "analog");

if (info->is_digital)

{

const char *interface;

if (info->digital.bits_per_primary != -1)

printf ("Bits Per Primary: %d\n", info->digital.bits_per_primary);

else

printf ("Bits Per Primary: undefined\n");

switch (info->digital.interface)

{

case DVI: interface = "DVI"; break;

case HDMI_A: interface = "HDMI-a"; break;

case HDMI_B: interface = "HDMI-b"; break;

case MDDI: interface = "MDDI"; break;

case DISPLAY_PORT: interface = "DisplayPort"; break;

case UNDEFINED: interface = "undefined"; break;

default: interface = "unknown"; break;

}

printf ("Interface: %s\n", interface);

printf ("RGB 4:4:4: %s\n", yesno (info->digital.rgb444));

printf ("YCrCb 4:4:4: %s\n", yesno (info->digital.ycrcb444));

printf ("YCrCb 4:2:2: %s\n", yesno (info->digital.ycrcb422));

}

else

{

const char *s;

printf ("Video Signal Level: %f\n", info->analog.video_signal_level);

printf ("Sync Signal Level: %f\n", info->analog.sync_signal_level);

printf ("Total Signal Level: %f\n", info->analog.total_signal_level);

printf ("Blank to Black: %s\n",

yesno (info->analog.blank_to_black));

printf ("Separate HV Sync: %s\n",

yesno (info->analog.separate_hv_sync));

printf ("Composite Sync on H: %s\n",

yesno (info->analog.composite_sync_on_h));

printf ("Serration on VSync: %s\n",

yesno (info->analog.serration_on_vsync));

switch (info->analog.color_type)

{

case UNDEFINED_COLOR: s = "undefined"; break;

case MONOCHROME: s = "monochrome"; break;

case RGB: s = "rgb"; break;

case OTHER_COLOR: s = "other color"; break;

default: s = "unknown"; break;

};

printf ("Color: %s\n", s);

}

if (info->width_mm == -1)

printf ("Width: undefined\n");

else

printf ("Width: %d mm\n", info->width_mm);

if (info->height_mm == -1)

printf ("Height: undefined\n");

else

printf ("Height: %d mm\n", info->height_mm);

if (info->aspect_ratio > 0)

printf ("Aspect Ratio: %f\n", info->aspect_ratio);

else

printf ("Aspect Ratio: undefined\n");

if (info->gamma >= 0)

printf ("Gamma: %f\n", info->gamma);

else

printf ("Gamma: undefined\n");

printf ("Standby: %s\n", yesno (info->standby));

printf ("Suspend: %s\n", yesno (info->suspend));

printf ("Active Off: %s\n", yesno (info->active_off));

printf ("SRGB is Standard: %s\n", yesno (info->srgb_is_standard));

printf ("Preferred Timing Includes Native: %s\n",

yesno (info->preferred_timing_includes_native));

printf ("Continuous Frequency: %s\n", yesno (info->continuous_frequency));

printf ("Red X: %f\n", info->red_x);

printf ("Red Y: %f\n", info->red_y);

printf ("Green X: %f\n", info->green_x);

printf ("Green Y: %f\n", info->green_y);

printf ("Blue X: %f\n", info->blue_x);

printf ("Blue Y: %f\n", info->blue_y);

printf ("White X: %f\n", info->white_x);

printf ("White Y: %f\n", info->white_y);

printf ("Established Timings:\n");

for (i = 0; i < 24; ++i)

{

Timing *timing = &(info->established[i]);

if (timing->frequency == 0)

break;

printf (" %d x %d @ %d Hz\n",

timing->width, timing->height, timing->frequency);

}

printf ("Standard Timings:\n");

for (i = 0; i < 8; ++i)

{

Timing *timing = &(info->standard[i]);

if (timing->frequency == 0)

break;

printf (" %d x %d @ %d Hz\n",

timing->width, timing->height, timing->frequency);

}

for (i = 0; i < info->n_detailed_timings; ++i)

{

DetailedTiming *timing = &(info->detailed_timings[i]);

const char *s;

printf ("Timing%s: \n",

(i == 0 && info->preferred_timing_includes_native)?

" (Preferred)" : "");

printf (" Pixel Clock: %d\n", timing->pixel_clock);

printf (" H Addressable: %d\n", timing->h_addr);

printf (" H Blank: %d\n", timing->h_blank);

printf (" H Front Porch: %d\n", timing->h_front_porch);

printf (" H Sync: %d\n", timing->h_sync);

printf (" V Addressable: %d\n", timing->v_addr);

printf (" V Blank: %d\n", timing->v_blank);

printf (" V Front Porch: %d\n", timing->v_front_porch);

printf (" V Sync: %d\n", timing->v_sync);

printf (" Width: %d mm\n", timing->width_mm);

printf (" Height: %d mm\n", timing->height_mm);

printf (" Right Border: %d\n", timing->right_border);

printf (" Top Border: %d\n", timing->top_border);

switch (timing->stereo)

{

default:

case NO_STEREO: s = "No Stereo"; break;

case FIELD_RIGHT: s = "Field Sequential, Right on Sync"; break;

case FIELD_LEFT: s = "Field Sequential, Left on Sync"; break;

case TWO_WAY_RIGHT_ON_EVEN: s = "Two-way, Right on Even"; break;

case TWO_WAY_LEFT_ON_EVEN: s = "Two-way, Left on Even"; break;

case FOUR_WAY_INTERLEAVED: s = "Four-way Interleaved"; break;

case SIDE_BY_SIDE: s = "Side-by-Side"; break;

}

printf (" Stereo: %s\n", s);

if (timing->digital_sync)

{

printf (" Digital Sync:\n");

printf (" composite: %s\n", yesno (timing->digital.composite));

printf (" serrations: %s\n", yesno (timing->digital.serrations));

printf (" negative vsync: %s\n",

yesno (timing->digital.negative_vsync));

printf (" negative hsync: %s\n",

yesno (timing->digital.negative_hsync));

}

else

{

printf (" Analog Sync:\n");

printf (" bipolar: %s\n", yesno (timing->analog.bipolar));

printf (" serrations: %s\n", yesno (timing->analog.serrations));

printf (" sync on green: %s\n", yesno (

timing->analog.sync_on_green));

}

}

printf ("Detailed Product information:\n");

printf (" Product Name: %s\n", info->dsc_product_name);

printf (" Serial Number: %s\n", info->dsc_serial_number);

printf (" Unspecified String: %s\n", info->dsc_string);

}