/* 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;
}
static unsigned char *
DDCRead_DDC2(int scrnIndex, I2CBusPtr pBus, int start, int len)
{
I2CDevPtr dev;
unsigned char W_Buffer[2];
int w_bytes;
unsigned char *R_Buffer;
int i;
xf86LoaderReqSymLists(i2cSymbols, NULL);
dev = xf86CreateI2CDevRec();
dev->DevName = "ddc2";
dev->SlaveAddr = 0xA0;
dev->ByteTimeout = 2200; /* VESA DDC spec 3 p. 43 (+10 %) */
dev->StartTimeout = 550;
dev->BitTimeout = 40;
dev->ByteTimeout = 40;
dev->AcknTimeout = 40;
dev->pI2CBus = pBus;
if (! xf86I2CDevInit(dev)) {
xf86DrvMsg(X_PROBED,scrnIndex,"No DDC2 device\n");
return NULL;
}
if (start < 0x100) {
w_bytes = 1;
W_Buffer[0] = start;
} else {
w_bytes = 2;
W_Buffer[0] = start & 0xFF;
W_Buffer[1] = (start & 0xFF00) >> 8;
}
R_Buffer = xcalloc(1,sizeof(unsigned char)
* (len));
for (i=0; i<RETRIES; i++) {
if (xf86I2CWriteRead(dev, W_Buffer,w_bytes, R_Buffer,len)) {
if (!DDC_checksum(R_Buffer,len)) {
xf86DestroyI2CDevRec(dev,TRUE);
return R_Buffer;
}
#ifdef DEBUG
else ErrorF("Checksum error in EDID block\n");
#endif
}
#ifdef DEBUG
else ErrorF("Error reading EDID block\n");
#endif
}
xf86DestroyI2CDevRec(dev,TRUE);
xfree(R_Buffer);
return NULL;
}
static unsigned char *
DDCRead_DDC2(int scrnIndex, I2CBusPtr pBus, int start, int len)
{
static char name[5] = "ddc2";
I2CDevPtr dev;
unsigned char W_Buffer[2];
int w_bytes;
unsigned char *R_Buffer;
int i;
if (!(dev = xf86I2CFindDev(pBus, 0x00A0))) {
dev = xf86CreateI2CDevRec();
dev->DevName = name;
dev->SlaveAddr = 0xA0;
dev->ByteTimeout = 2200; /* VESA DDC spec 3 p. 43 (+10 %) */
dev->StartTimeout = 550;
dev->BitTimeout = 40;
dev->ByteTimeout = 40;
dev->AcknTimeout = 40;
dev->pI2CBus = pBus;
if (!xf86I2CDevInit(dev)) {
LOG("No DDC2 device\n");
return NULL;
}
}
if (start < 0x100) {
w_bytes = 1;
W_Buffer[0] = start;
} else {
w_bytes = 2;
W_Buffer[0] = start & 0xFF;
W_Buffer[1] = (start & 0xFF00) >> 8;
}
R_Buffer = (unsigned char *)IOMalloc(sizeof(unsigned char) * len);
if (!R_Buffer) return NULL;
bzero(R_Buffer, sizeof(unsigned char) * len);
for (i=0; i<RETRIES; i++) {
if (xf86I2CWriteRead(dev, W_Buffer,w_bytes, R_Buffer,len)) {
if (!DDC_checksum(R_Buffer,len))
return R_Buffer;
else LOGV("Checksum error in EDID block\n");
}
else LOGV("Error reading EDID block\n");
}
xf86DestroyI2CDevRec(dev,TRUE);
IOFree(R_Buffer, sizeof(unsigned char) * len);
return NULL;
}
