xenocara/xserver/hw/xfree86/ddc/ddc.c
2011-11-05 13:32:40 +00:00

504 lines
12 KiB
C

/* xf86DDC.c
*
* Copyright 1998,1999 by Egbert Eich <Egbert.Eich@Physik.TU-Darmstadt.DE>
*/
/*
* A note on terminology. DDC1 is the original dumb serial protocol, and
* can only do up to 128 bytes of EDID. DDC2 is I2C-encapsulated and
* introduces extension blocks. EDID is the old display identification
* block, DisplayID is the new one.
*/
#ifdef HAVE_XORG_CONFIG_H
#include <xorg-config.h>
#endif
#include "misc.h"
#include "xf86.h"
#include "xf86_OSproc.h"
#include "xf86DDC.h"
#include <string.h>
#define RETRIES 4
typedef enum {
DDCOPT_NODDC1,
DDCOPT_NODDC2,
DDCOPT_NODDC
} DDCOpts;
static const OptionInfoRec DDCOptions[] = {
{ DDCOPT_NODDC1, "NoDDC1", OPTV_BOOLEAN, {0}, FALSE },
{ DDCOPT_NODDC2, "NoDDC2", OPTV_BOOLEAN, {0}, FALSE },
{ DDCOPT_NODDC, "NoDDC", OPTV_BOOLEAN, {0}, FALSE },
{ -1, NULL, OPTV_NONE, {0}, FALSE },
};
/* DDC1 */
static int
find_start(unsigned int *ptr)
{
unsigned int comp[9], test[9];
int i,j;
for (i=0;i<9;i++){
comp[i] = *(ptr++);
test[i] = 1;
}
for (i=0;i<127;i++){
for (j=0;j<9;j++){
test[j] = test[j] & !(comp[j] ^ *(ptr++));
}
}
for (i=0;i<9;i++)
if (test[i]) return i+1;
return -1;
}
static unsigned char *
find_header(unsigned char *block)
{
unsigned char *ptr, *head_ptr, *end;
unsigned char header[]={0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00};
ptr = block;
end = block + EDID1_LEN;
while (ptr<end) {
int i;
head_ptr = ptr;
for (i=0;i<8;i++){
if (header[i] != *(head_ptr++)) break;
if (head_ptr == end) head_ptr = block;
}
if (i==8) break;
ptr++;
}
if (ptr == end) return NULL;
return ptr;
}
static unsigned char *
resort(unsigned char *s_block)
{
unsigned char *d_new, *d_ptr, *d_end, *s_ptr, *s_end;
unsigned char tmp;
s_end = s_block + EDID1_LEN;
d_new = malloc(EDID1_LEN);
if (!d_new) return NULL;
d_end = d_new + EDID1_LEN;
s_ptr = find_header(s_block);
if (!s_ptr) return NULL;
for (d_ptr=d_new;d_ptr<d_end;d_ptr++){
tmp = *(s_ptr++);
*d_ptr = tmp;
if (s_ptr == s_end) s_ptr = s_block;
}
free(s_block);
return d_new;
}
static int
DDC_checksum(const unsigned char *block, int len)
{
int i, result = 0;
int not_null = 0;
for (i=0;i<len;i++) {
not_null |= block[i];
result += block[i];
}
#ifdef DEBUG
if (result & 0xFF) ErrorF("DDC checksum not correct\n");
if (!not_null) ErrorF("DDC read all Null\n");
#endif
/* catch the trivial case where all bytes are 0 */
if (!not_null) return 1;
return result&0xFF;
}
static unsigned char *
GetEDID_DDC1(unsigned int *s_ptr)
{
unsigned char *d_block, *d_pos;
unsigned int *s_pos, *s_end;
int s_start;
int i,j;
s_start = find_start(s_ptr);
if (s_start==-1) return NULL;
s_end = s_ptr + NUM;
s_pos = s_ptr + s_start;
d_block=malloc(EDID1_LEN);
if (!d_block) return NULL;
d_pos = d_block;
for (i=0;i<EDID1_LEN;i++) {
for (j=0;j<8;j++) {
*d_pos <<= 1;
if (*s_pos) {
*d_pos |= 0x01;
}
s_pos++; if (s_pos == s_end) s_pos=s_ptr;
};
s_pos++; if (s_pos == s_end) s_pos=s_ptr;
d_pos++;
}
free(s_ptr);
if (d_block && DDC_checksum(d_block,EDID1_LEN)) {
free(d_block);
return NULL;
}
return (resort(d_block));
}
/* fetch entire EDID record; DDC bit needs to be masked */
static unsigned int *
FetchEDID_DDC1(register ScrnInfoPtr pScrn,
register unsigned int (*read_DDC)(ScrnInfoPtr))
{
int count = NUM;
unsigned int *ptr, *xp;
ptr=xp=malloc(sizeof(int)*NUM);
if (!ptr) return NULL;
do {
/* wait for next retrace */
*xp = read_DDC(pScrn);
xp++;
} while(--count);
return ptr;
}
/* test if DDC1 return 0 if not */
static Bool
TestDDC1(ScrnInfoPtr pScrn, unsigned int (*read_DDC)(ScrnInfoPtr))
{
int old, count;
old = read_DDC(pScrn);
count = HEADER * BITS_PER_BYTE;
do {
/* wait for next retrace */
if (old != read_DDC(pScrn)) break;
} while(count--);
return count;
}
/*
* read EDID record , pass it to callback function to interpret.
* callback function will store it for further use by calling
* function; it will also decide if we need to reread it
*/
static unsigned char *
EDIDRead_DDC1(ScrnInfoPtr pScrn, DDC1SetSpeedProc DDCSpeed,
unsigned int (*read_DDC)(ScrnInfoPtr))
{
unsigned char *EDID_block = NULL;
int count = RETRIES;
if (!read_DDC) {
xf86DrvMsg(pScrn->scrnIndex, X_PROBED,
"chipset doesn't support DDC1\n");
return NULL;
};
if (TestDDC1(pScrn,read_DDC)==-1) {
xf86DrvMsg(pScrn->scrnIndex, X_PROBED, "No DDC signal\n");
return NULL;
};
if (DDCSpeed) DDCSpeed(pScrn,DDC_FAST);
do {
EDID_block = GetEDID_DDC1(FetchEDID_DDC1(pScrn,read_DDC));
count --;
} while (!EDID_block && count);
if (DDCSpeed) DDCSpeed(pScrn,DDC_SLOW);
return EDID_block;
}
/**
* Attempts to probe the monitor for EDID information, if NoDDC and NoDDC1 are
* unset. EDID information blocks are interpreted and the results returned in
* an xf86MonPtr.
*
* This function does not affect the list of modes used by drivers -- it is up
* to the driver to decide policy on what to do with EDID information.
*
* @return pointer to a new xf86MonPtr containing the EDID information.
* @return NULL if no monitor attached or failure to interpret the EDID.
*/
xf86MonPtr
xf86DoEDID_DDC1(int scrnIndex, DDC1SetSpeedProc DDC1SetSpeed,
unsigned int (*DDC1Read)(ScrnInfoPtr))
{
ScrnInfoPtr pScrn = xf86Screens[scrnIndex];
unsigned char *EDID_block = NULL;
xf86MonPtr tmp = NULL;
/* Default DDC and DDC1 to enabled. */
Bool noddc = FALSE, noddc1 = FALSE;
OptionInfoPtr options;
options = xnfalloc(sizeof(DDCOptions));
(void)memcpy(options, DDCOptions, sizeof(DDCOptions));
xf86ProcessOptions(pScrn->scrnIndex, pScrn->options, options);
xf86GetOptValBool(options, DDCOPT_NODDC, &noddc);
xf86GetOptValBool(options, DDCOPT_NODDC1, &noddc1);
free(options);
if (noddc || noddc1)
return NULL;
OsBlockSignals();
EDID_block = EDIDRead_DDC1(pScrn,DDC1SetSpeed,DDC1Read);
OsReleaseSignals();
if (EDID_block){
tmp = xf86InterpretEDID(scrnIndex,EDID_block);
}
#ifdef DEBUG
else ErrorF("No EDID block returned\n");
if (!tmp)
ErrorF("Cannot interpret EDID block\n");
#endif
return tmp;
}
/* DDC2 */
static I2CDevPtr
DDC2MakeDevice(I2CBusPtr pBus, int address, char *name)
{
I2CDevPtr dev = NULL;
if (!(dev = xf86I2CFindDev(pBus, address))) {
dev = xf86CreateI2CDevRec();
dev->DevName = name;
dev->SlaveAddr = address;
dev->ByteTimeout = 2200; /* VESA DDC spec 3 p. 43 (+10 %) */
dev->StartTimeout = 550;
dev->BitTimeout = 40;
dev->AcknTimeout = 40;
dev->pI2CBus = pBus;
if (!xf86I2CDevInit(dev)) {
xf86DrvMsg(pBus->scrnIndex, X_PROBED, "No DDC2 device\n");
return NULL;
}
}
return dev;
}
static I2CDevPtr
DDC2Init(int scrnIndex, I2CBusPtr pBus)
{
I2CDevPtr dev = NULL;
/*
* Slow down the bus so that older monitors don't
* miss things.
*/
pBus->RiseFallTime = 20;
dev = DDC2MakeDevice(pBus, 0x00A0, "ddc2");
if (xf86I2CProbeAddress(pBus, 0x0060))
DDC2MakeDevice(pBus, 0x0060, "E-EDID segment register");
return dev;
}
/* Mmmm, smell the hacks */
static void
EEDIDStop(I2CDevPtr d)
{
}
/* block is the EDID block number. a segment is two blocks. */
static Bool
DDC2Read(I2CDevPtr dev, int block, unsigned char *R_Buffer)
{
unsigned char W_Buffer[1];
int i, segment;
I2CDevPtr seg;
void (*stop)(I2CDevPtr);
for (i = 0; i < RETRIES; i++) {
/* Stop bits reset the segment pointer to 0, so be careful here. */
segment = block >> 1;
if (segment) {
Bool b;
if (!(seg = xf86I2CFindDev(dev->pI2CBus, 0x0060)))
return FALSE;
W_Buffer[0] = segment;
stop = dev->pI2CBus->I2CStop;
dev->pI2CBus->I2CStop = EEDIDStop;
b = xf86I2CWriteRead(seg, W_Buffer, 1, NULL, 0);
dev->pI2CBus->I2CStop = stop;
if (!b) {
dev->pI2CBus->I2CStop(dev);
continue;
}
}
W_Buffer[0] = (block & 0x01) * EDID1_LEN;
if (xf86I2CWriteRead(dev, W_Buffer, 1, R_Buffer, EDID1_LEN)) {
if (!DDC_checksum(R_Buffer, EDID1_LEN))
return TRUE;
}
}
return FALSE;
}
/**
* Attempts to probe the monitor for EDID information, if NoDDC and NoDDC2 are
* unset. EDID information blocks are interpreted and the results returned in
* an xf86MonPtr. Unlike xf86DoEDID_DDC[12](), this function will return
* the complete EDID data, including all extension blocks, if the 'complete'
* parameter is TRUE;
*
* This function does not affect the list of modes used by drivers -- it is up
* to the driver to decide policy on what to do with EDID information.
*
* @return pointer to a new xf86MonPtr containing the EDID information.
* @return NULL if no monitor attached or failure to interpret the EDID.
*/
xf86MonPtr
xf86DoEEDID(int scrnIndex, I2CBusPtr pBus, Bool complete)
{
ScrnInfoPtr pScrn = xf86Screens[scrnIndex];
unsigned char *EDID_block = NULL;
xf86MonPtr tmp = NULL;
I2CDevPtr dev = NULL;
/* Default DDC and DDC2 to enabled. */
Bool noddc = FALSE, noddc2 = FALSE;
OptionInfoPtr options;
options = malloc(sizeof(DDCOptions));
if (!options)
return NULL;
memcpy(options, DDCOptions, sizeof(DDCOptions));
xf86ProcessOptions(pScrn->scrnIndex, pScrn->options, options);
xf86GetOptValBool(options, DDCOPT_NODDC, &noddc);
xf86GetOptValBool(options, DDCOPT_NODDC2, &noddc2);
free(options);
if (noddc || noddc2)
return NULL;
if (!(dev = DDC2Init(scrnIndex, pBus)))
return NULL;
EDID_block = calloc(1, EDID1_LEN);
if (!EDID_block)
return NULL;
if (DDC2Read(dev, 0, EDID_block)) {
int i, n = EDID_block[0x7e];
if (complete && n) {
EDID_block = realloc(EDID_block, EDID1_LEN * (1+n));
for (i = 0; i < n; i++)
DDC2Read(dev, i+1, EDID_block + (EDID1_LEN * (1+i)));
}
tmp = xf86InterpretEEDID(scrnIndex, EDID_block);
}
if (tmp && complete)
tmp->flags |= MONITOR_EDID_COMPLETE_RAWDATA;
return tmp;
}
/**
* Attempts to probe the monitor for EDID information, if NoDDC and NoDDC2 are
* unset. EDID information blocks are interpreted and the results returned in
* an xf86MonPtr.
*
* This function does not affect the list of modes used by drivers -- it is up
* to the driver to decide policy on what to do with EDID information.
*
* @return pointer to a new xf86MonPtr containing the EDID information.
* @return NULL if no monitor attached or failure to interpret the EDID.
*/
xf86MonPtr
xf86DoEDID_DDC2(int scrnIndex, I2CBusPtr pBus)
{
return xf86DoEEDID(scrnIndex, pBus, FALSE);
}
/* XXX write me */
static void *
DDC2ReadDisplayID(void)
{
return FALSE;
}
/**
* Attempts to probe the monitor for DisplayID information, if NoDDC and
* NoDDC2 are unset. DisplayID blocks are interpreted and the results
* returned in an xf86MonPtr.
*
* This function does not affect the list of modes used by drivers -- it is up
* to the driver to decide policy on what to do with DisplayID information.
*
* @return pointer to a new xf86MonPtr containing the DisplayID information.
* @return NULL if no monitor attached or failure to interpret the DisplayID.
*/
xf86MonPtr
xf86DoDisplayID(int scrnIndex, I2CBusPtr pBus)
{
ScrnInfoPtr pScrn = xf86Screens[scrnIndex];
unsigned char *did = NULL;
xf86MonPtr tmp = NULL;
I2CDevPtr dev = NULL;
/* Default DDC and DDC2 to enabled. */
Bool noddc = FALSE, noddc2 = FALSE;
OptionInfoPtr options;
options = malloc(sizeof(DDCOptions));
if (!options)
return NULL;
memcpy(options, DDCOptions, sizeof(DDCOptions));
xf86ProcessOptions(pScrn->scrnIndex, pScrn->options, options);
xf86GetOptValBool(options, DDCOPT_NODDC, &noddc);
xf86GetOptValBool(options, DDCOPT_NODDC2, &noddc2);
free(options);
if (noddc || noddc2)
return NULL;
if (!(dev = DDC2Init(scrnIndex, pBus)))
return NULL;
if ((did = DDC2ReadDisplayID())) {
tmp = calloc(1, sizeof(*tmp));
if (!tmp)
return NULL;
tmp->scrnIndex = scrnIndex;
tmp->flags |= MONITOR_DISPLAYID;
tmp->rawData = did;
}
return tmp;
}