#include <stdio.h>
#include <stdlib.h>
#include <string.h>
// TODO: rewrite
// FIXME: cleanup 'static' variables
typedef unsigned char byte;
/* byte must be 8 bits */
/* int must be at least 16 bits */
/* long must be at least 32 bits */
#define DIE_MSG( x ) \
{ MSG( x ); exit( 1 ); }
#define UPPER_NIBBLE( x ) \
(((128|64|32|16) & (x)) >> 4)
#define LOWER_NIBBLE( x ) \
((1|2|4|8) & (x))
#define COMBINE_HI_8LO( hi, lo ) \
( (((unsigned)hi) << 8) | (unsigned)lo )
#define COMBINE_HI_4LO( hi, lo ) \
( (((unsigned)hi) << 4) | (unsigned)lo )
const byte edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0x00 };
const byte edid_v1_descriptor_flag[] = { 0x00, 0x00 };
#define EDID_LENGTH 0x80
#define EDID_HEADER 0x00
#define EDID_HEADER_END 0x07
#define ID_MANUFACTURER_NAME 0x08
#define ID_MANUFACTURER_NAME_END 0x09
#define ID_MODEL 0x0a
#define ID_SERIAL_NUMBER 0x0c
#define MANUFACTURE_WEEK 0x10
#define MANUFACTURE_YEAR 0x11
#define EDID_STRUCT_VERSION 0x12
#define EDID_STRUCT_REVISION 0x13
#define DPMS_FLAGS 0x18
#define ESTABLISHED_TIMING_1 0x23
#define ESTABLISHED_TIMING_2 0x24
#define MANUFACTURERS_TIMINGS 0x25
#define DETAILED_TIMING_DESCRIPTIONS_START 0x36
#define DETAILED_TIMING_DESCRIPTION_SIZE 18
#define NO_DETAILED_TIMING_DESCRIPTIONS 4
#define DETAILED_TIMING_DESCRIPTION_1 0x36
#define DETAILED_TIMING_DESCRIPTION_2 0x48
#define DETAILED_TIMING_DESCRIPTION_3 0x5a
#define DETAILED_TIMING_DESCRIPTION_4 0x6c
#define PIXEL_CLOCK_LO (unsigned)dtd[ 0 ]
#define PIXEL_CLOCK_HI (unsigned)dtd[ 1 ]
#define PIXEL_CLOCK (COMBINE_HI_8LO( PIXEL_CLOCK_HI,PIXEL_CLOCK_LO )*10000)
#define H_ACTIVE_LO (unsigned)dtd[ 2 ]
#define H_BLANKING_LO (unsigned)dtd[ 3 ]
#define H_ACTIVE_HI UPPER_NIBBLE( (unsigned)dtd[ 4 ] )
#define H_ACTIVE COMBINE_HI_8LO( H_ACTIVE_HI, H_ACTIVE_LO )
#define H_BLANKING_HI LOWER_NIBBLE( (unsigned)dtd[ 4 ] )
#define H_BLANKING COMBINE_HI_8LO( H_BLANKING_HI, H_BLANKING_LO )
#define V_ACTIVE_LO (unsigned)dtd[ 5 ]
#define V_BLANKING_LO (unsigned)dtd[ 6 ]
#define V_ACTIVE_HI UPPER_NIBBLE( (unsigned)dtd[ 7 ] )
#define V_ACTIVE COMBINE_HI_8LO( V_ACTIVE_HI, V_ACTIVE_LO )
#define V_BLANKING_HI LOWER_NIBBLE( (unsigned)dtd[ 7 ] )
#define V_BLANKING COMBINE_HI_8LO( V_BLANKING_HI, V_BLANKING_LO )
#define H_SYNC_OFFSET_LO (unsigned)dtd[ 8 ]
#define H_SYNC_WIDTH_LO (unsigned)dtd[ 9 ]
#define V_SYNC_OFFSET_LO UPPER_NIBBLE( (unsigned)dtd[ 10 ] )
#define V_SYNC_WIDTH_LO LOWER_NIBBLE( (unsigned)dtd[ 10 ] )
#define V_SYNC_WIDTH_HI ((unsigned)dtd[ 11 ] & (1|2))
#define V_SYNC_OFFSET_HI (((unsigned)dtd[ 11 ] & (4|8)) >> 2)
#define H_SYNC_WIDTH_HI (((unsigned)dtd[ 11 ] & (16|32)) >> 4)
#define H_SYNC_OFFSET_HI (((unsigned)dtd[ 11 ] & (64|128)) >> 6)
#define V_SYNC_WIDTH COMBINE_HI_4LO( V_SYNC_WIDTH_HI, V_SYNC_WIDTH_LO )
#define V_SYNC_OFFSET COMBINE_HI_4LO( V_SYNC_OFFSET_HI, V_SYNC_OFFSET_LO )
#define H_SYNC_WIDTH COMBINE_HI_4LO( H_SYNC_WIDTH_HI, H_SYNC_WIDTH_LO )
#define H_SYNC_OFFSET COMBINE_HI_4LO( H_SYNC_OFFSET_HI, H_SYNC_OFFSET_LO )
#define H_SIZE_LO (unsigned)dtd[ 12 ]
#define V_SIZE_LO (unsigned)dtd[ 13 ]
#define H_SIZE_HI UPPER_NIBBLE( (unsigned)dtd[ 14 ] )
#define V_SIZE_HI LOWER_NIBBLE( (unsigned)dtd[ 14 ] )
#define H_SIZE COMBINE_HI_8LO( H_SIZE_HI, H_SIZE_LO )
#define V_SIZE COMBINE_HI_8LO( V_SIZE_HI, V_SIZE_LO )
#define H_BORDER (unsigned)dtd[ 15 ]
#define V_BORDER (unsigned)dtd[ 16 ]
#define FLAGS (unsigned)dtd[ 17 ]
#define INTERLACED (FLAGS&128)
#define SYNC_TYPE (FLAGS&3<<3) /* bits 4,3 */
#define SYNC_SEPARATE (3<<3)
#define HSYNC_POSITIVE (FLAGS & 4)
#define VSYNC_POSITIVE (FLAGS & 2)
#define MONITOR_NAME 0xfc
#define MONITOR_LIMITS 0xfd
#define UNKNOWN_DESCRIPTOR -1
#define DETAILED_TIMING_BLOCK -2
#define DESCRIPTOR_DATA 5
#define V_MIN_RATE block[ 5 ]
#define V_MAX_RATE block[ 6 ]
#define H_MIN_RATE block[ 7 ]
#define H_MAX_RATE block[ 8 ]
#define MAX_PIXEL_CLOCK (((int)block[ 9 ]) * 10)
#define GTF_SUPPORT block[10]
#define DPMS_ACTIVE_OFF (1 << 5)
#define DPMS_SUSPEND (1 << 6)
#define DPMS_STANDBY (1 << 7)
char* myname;
void MSG( const char* x )
{
fprintf( stderr, "%s: %s\n", myname, x );
}
int
parse_edid( byte* edid );
int
parse_timing_description( byte* dtd );
int
parse_monitor_limits( byte* block );
int
block_type( byte* block );
char*
get_monitor_name( byte const* block );
char*
get_vendor_sign( byte const* block );
int
parse_dpms_capabilities( byte flags );
int
main( int argc, char** argv )
{
byte edid[ EDID_LENGTH ];
FILE* edid_file;
myname = argv[ 0 ];
fprintf( stderr, "%s: parse-edid version %s\n", myname, VERSION );
if ( argc > 2 )
{
DIE_MSG( "syntax: [input EDID file]" );
}
else
{
if ( argc == 2 )
{
edid_file = fopen( argv[ 1 ], "rb" );
if ( !edid_file )
DIE_MSG( "unable to open file for input" );
}
else
edid_file = stdin;
}
if ( fread( edid, sizeof( byte ), EDID_LENGTH, edid_file )
!= EDID_LENGTH )
{
DIE_MSG( "IO error reading EDID" );
}
fclose( edid_file );
return parse_edid( edid );
}
int
parse_edid( byte* edid )
{
unsigned i;
byte* block;
char* monitor_name = NULL;
char monitor_alt_name[100];
byte checksum = 0;
char *vendor_sign;
int ret = 0;
for( i = 0; i < EDID_LENGTH; i++ )
checksum += edid[ i ];
if ( checksum != 0 ) {
MSG( "EDID checksum failed - data is corrupt. Continuing anyway." );
ret = 1;
} else
MSG( "EDID checksum passed." );
if ( strncmp( edid+EDID_HEADER, edid_v1_header, EDID_HEADER_END+1 ) )
{
MSG( "first bytes don't match EDID version 1 header" );
MSG( "do not trust output (if any)." );
ret = 1;
}
printf( "\n\t# EDID version %d revision %d\n", (int)edid[EDID_STRUCT_VERSION],(int)edid[EDID_STRUCT_REVISION] );
vendor_sign = get_vendor_sign( edid + ID_MANUFACTURER_NAME );
printf( "Section \"Monitor\"\n" );
block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
for( i = 0; i < NO_DETAILED_TIMING_DESCRIPTIONS; i++,
block += DETAILED_TIMING_DESCRIPTION_SIZE )
{
if ( block_type( block ) == MONITOR_NAME )
{
monitor_name = get_monitor_name( block );
break;
}
}
if (!monitor_name) {
/* Stupid djgpp hasn't snprintf so we have to hack something together */
if(strlen(vendor_sign) + 10 > sizeof(monitor_alt_name))
vendor_sign[3] = 0;
sprintf(monitor_alt_name, "%s:%02x%02x",
vendor_sign, edid[ID_MODEL], edid[ID_MODEL+1]) ;
monitor_name = monitor_alt_name;
}
printf( "\tIdentifier \"%s\"\n", monitor_name );
printf( "\tVendorName \"%s\"\n", vendor_sign );
printf( "\tModelName \"%s\"\n", monitor_name );
block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
for( i = 0; i < NO_DETAILED_TIMING_DESCRIPTIONS; i++,
block += DETAILED_TIMING_DESCRIPTION_SIZE )
{
if ( block_type( block ) == MONITOR_LIMITS )
parse_monitor_limits( block );
}
parse_dpms_capabilities(edid[DPMS_FLAGS]);
block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
for( i = 0; i < NO_DETAILED_TIMING_DESCRIPTIONS; i++,
block += DETAILED_TIMING_DESCRIPTION_SIZE )
{
if ( block_type( block ) == DETAILED_TIMING_BLOCK )
parse_timing_description( block );
}
printf( "EndSection\n" );
return ret;
}
int
parse_timing_description( byte* dtd )
{
int htotal, vtotal;
htotal = H_ACTIVE + H_BLANKING;
vtotal = V_ACTIVE + V_BLANKING;
printf( "\tMode \t\"%dx%d\"", H_ACTIVE, V_ACTIVE );
printf( "\t# vfreq %3.3fHz, hfreq %6.3fkHz\n",
(double)PIXEL_CLOCK/((double)vtotal*(double)htotal),
(double)PIXEL_CLOCK/(double)(htotal*1000));
printf( "\t\tDotClock\t%f\n", (double)PIXEL_CLOCK/1000000.0 );
printf( "\t\tHTimings\t%u %u %u %u\n", H_ACTIVE,
H_ACTIVE+H_SYNC_OFFSET,
H_ACTIVE+H_SYNC_OFFSET+H_SYNC_WIDTH,
htotal );
printf( "\t\tVTimings\t%u %u %u %u\n", V_ACTIVE,
V_ACTIVE+V_SYNC_OFFSET,
V_ACTIVE+V_SYNC_OFFSET+V_SYNC_WIDTH,
vtotal );
if ( INTERLACED || (SYNC_TYPE == SYNC_SEPARATE)) {
printf( "\t\tFlags\t%s\"%sHSync\" \"%sVSync\"\n",
INTERLACED ? "\"Interlace\" ": "",
HSYNC_POSITIVE ? "+": "-",
VSYNC_POSITIVE ? "+": "-");
}
printf( "\tEndMode\n" );
return 0;
}
int
block_type( byte* block )
{
if ( !strncmp( edid_v1_descriptor_flag, block, 2 ) )
{
printf("\t# Block type: 2:%x 3:%x\n", block[2], block[3]);
/* descriptor */
if ( block[ 2 ] != 0 )
return UNKNOWN_DESCRIPTOR;
return block[ 3 ];
} else {
/* detailed timing block */
return DETAILED_TIMING_BLOCK;
}
}
char*
get_monitor_name( byte const* block )
{
static char name[ 13 ];
unsigned i;
byte const* ptr = block + DESCRIPTOR_DATA;
for( i = 0; i < 13; i++, ptr++ )
{
if ( *ptr == 0xa )
{
name[ i ] = 0;
return name;
}
name[ i ] = *ptr;
}
return name;
}
char* get_vendor_sign( byte const* block )
{
static char sign[4];
unsigned short h;
/*
08h WORD big-endian manufacturer ID (see #00136)
bits 14-10: first letter (01h='A', 02h='B', etc.)
bits 9-5: second letter
bits 4-0: third letter
*/
h = COMBINE_HI_8LO(block[0], block[1]);
sign[0] = ((h>>10) & 0x1f) + 'A' - 1;
sign[1] = ((h>>5) & 0x1f) + 'A' - 1;
sign[2] = (h & 0x1f) + 'A' - 1;
sign[3] = 0;
return sign;
}
int
parse_monitor_limits( byte* block )
{
printf( "\tHorizSync %u-%u\n", H_MIN_RATE, H_MAX_RATE );
printf( "\tVertRefresh %u-%u\n", V_MIN_RATE, V_MAX_RATE );
if ( MAX_PIXEL_CLOCK == 10*0xff )
printf( "\t# Max dot clock not given\n" );
else
printf( "\t# Max dot clock (video bandwidth) %u MHz\n", (int)MAX_PIXEL_CLOCK );
if ( GTF_SUPPORT )
{
printf( "\t# EDID version 3 GTF given: contact author\n" );
}
return 0;
}
int
parse_dpms_capabilities(byte flags)
{
printf("\t# DPMS capabilities: Active off:%s Suspend:%s Standby:%s\n\n",
(flags & DPMS_ACTIVE_OFF) ? "yes" : "no",
(flags & DPMS_SUSPEND) ? "yes" : "no",
(flags & DPMS_STANDBY) ? "yes" : "no");
return 0;
}
