1 files changed, 126 insertions, 0 deletions
diff --git a/src/alp_i2c.c b/src/alp_i2c.c
new file mode 100644
index 0000000..78d5406
--- /dev/null
+++ b/src/alp_i2c.c
@@ -0,0 +1,126 @@
+/* (c) Itai Nahshon */
+
+/* $XFree86: xc/programs/Xserver/hw/xfree86/drivers/cirrus/alp_i2c.c,v 1.3 2000/12/06 15:35:15 eich Exp $ */
+
+#include "xf86.h"
+#include "xf86_OSproc.h"
+#include "xf86_ansic.h"
+#include "compiler.h"
+
+#include "xf86Pci.h"
+#include "xf86PciInfo.h"
+
+#include "vgaHW.h"
+
+#include "cir.h"
+#define _ALP_PRIVATE_
+#include "alp.h"
+
+/*
+ * Switch between internal I2C bus and external (DDC) bus.
+ * There is one I2C port controlled bu SR08 and the programmable
+ * outputs control a multiplexer.
+ */
+static Bool
+AlpI2CSwitchToBus(I2CBusPtr b)
+{
+	CirPtr pCir = ((CirPtr)b->DriverPrivate.ptr);
+	vgaHWPtr hwp = VGAHWPTR(pCir->pScrn);
+	CARD8 reg = hwp->readGr(hwp, 0x17);
+	if (b == pCir->I2CPtr1) {
+	    if ((reg & 0x60) == 0)
+  		return TRUE;
+	    reg &= ~0x60;
+	}
+	else if(b == pCir->I2CPtr2) {
+	    if ((reg & 0x60) != 0)
+  		return TRUE;
+	    reg |= 0x60;
+	} else 	return FALSE;
+
+	/* ErrorF("AlpI2CSwitchToBus: \"%s\"\n", b->BusName); */
+	hwp->writeGr(hwp, 0x17, reg);
+	return TRUE;
+}
+
+static void
+AlpI2CPutBits(I2CBusPtr b, int clock,  int data)
+{
+	unsigned int reg = 0xfc;
+	CirPtr pCir = ((CirPtr)b->DriverPrivate.ptr);
+	vgaHWPtr hwp = VGAHWPTR(pCir->pScrn);
+
+	if (!AlpI2CSwitchToBus(b))
+		return;
+
+	if (clock) reg |= 1;
+	if (data)  reg |= 2;
+	hwp->writeSeq(hwp, 0x08, reg);
+	/* ErrorF("AlpI2CPutBits: %d %d\n", clock, data); */
+}
+
+static void
+AlpI2CGetBits(I2CBusPtr b, int *clock, int *data)
+{
+	unsigned int reg;
+	CirPtr pCir = ((CirPtr)b->DriverPrivate.ptr);
+	vgaHWPtr hwp = VGAHWPTR(pCir->pScrn);
+
+	if (!AlpI2CSwitchToBus(b))
+		return;
+
+	reg = hwp->readSeq(hwp, 0x08);
+	*clock = (reg & 0x04) != 0;
+	*data  = (reg & 0x80) != 0;
+	/* ErrorF("AlpI2CGetBits: %d %d\n", *clock, *data); */
+}
+
+Bool
+AlpI2CInit(ScrnInfoPtr pScrn)
+{
+	CirPtr pCir = CIRPTR(pScrn);
+	I2CBusPtr I2CPtr;
+
+#ifdef ALP_DEBUG
+	ErrorF("AlpI2CInit\n");
+#endif
+
+	switch(pCir->Chipset) {
+	case PCI_CHIP_GD5446:
+	case PCI_CHIP_GD5480:
+		break;
+	default:
+		return FALSE;
+	}
+
+
+	I2CPtr = xf86CreateI2CBusRec();
+	if (!I2CPtr) return FALSE;
+
+	pCir->I2CPtr1 = I2CPtr;
+
+	I2CPtr->BusName    = "I2C bus 1";
+	I2CPtr->scrnIndex  = pScrn->scrnIndex;
+	I2CPtr->I2CPutBits = AlpI2CPutBits;
+	I2CPtr->I2CGetBits = AlpI2CGetBits;
+	I2CPtr->DriverPrivate.ptr = pCir;
+
+	if (!xf86I2CBusInit(I2CPtr))
+		return FALSE;
+
+	I2CPtr = xf86CreateI2CBusRec();
+	if (!I2CPtr) return FALSE;
+
+	pCir->I2CPtr2 = I2CPtr;
+
+	I2CPtr->BusName    = "I2C bus 2";
+	I2CPtr->scrnIndex  = pScrn->scrnIndex;
+	I2CPtr->I2CPutBits = AlpI2CPutBits;
+	I2CPtr->I2CGetBits = AlpI2CGetBits;
+	I2CPtr->DriverPrivate.ptr = pCir;
+
+	if (!xf86I2CBusInit(I2CPtr))
+		return FALSE;
+
+	return TRUE;
+}