alp_i2c.c revision 63847c39 
1/* (c) Itai Nahshon */
2
3#ifdef HAVE_CONFIG_H
4#include "config.h"
5#endif
6
7#include "xf86.h"
8#include "xf86_OSproc.h"
9#include "compiler.h"
10
11#include "xf86Pci.h"
12
13#include "vgaHW.h"
14
15#include "cir.h"
16#define _ALP_PRIVATE_
17#include "alp.h"
18
19/*
20 * Switch between internal I2C bus and external (DDC) bus.
21 * There is one I2C port controlled bu SR08 and the programmable
22 * outputs control a multiplexer.
23 */
24static Bool
25AlpI2CSwitchToBus(I2CBusPtr b)
26{
27	CirPtr pCir = ((CirPtr)b->DriverPrivate.ptr);
28	vgaHWPtr hwp = VGAHWPTR(pCir->pScrn);
29	CARD8 reg = hwp->readGr(hwp, 0x17);
30	if (b == pCir->I2CPtr1) {
31	    if ((reg & 0x60) == 0)
32  		return TRUE;
33	    reg &= ~0x60;
34	}
35	else if(b == pCir->I2CPtr2) {
36	    if ((reg & 0x60) != 0)
37  		return TRUE;
38	    reg |= 0x60;
39	} else 	return FALSE;
40
41	/* ErrorF("AlpI2CSwitchToBus: \"%s\"\n", b->BusName); */
42	hwp->writeGr(hwp, 0x17, reg);
43	return TRUE;
44}
45
46static void
47AlpI2CPutBits(I2CBusPtr b, int clock,  int data)
48{
49	unsigned int reg = 0xfc;
50	CirPtr pCir = ((CirPtr)b->DriverPrivate.ptr);
51	vgaHWPtr hwp = VGAHWPTR(pCir->pScrn);
52
53	if (!AlpI2CSwitchToBus(b))
54		return;
55
56	if (clock) reg |= 1;
57	if (data)  reg |= 2;
58	hwp->writeSeq(hwp, 0x08, reg);
59	/* ErrorF("AlpI2CPutBits: %d %d\n", clock, data); */
60}
61
62static void
63AlpI2CGetBits(I2CBusPtr b, int *clock, int *data)
64{
65	unsigned int reg;
66	CirPtr pCir = ((CirPtr)b->DriverPrivate.ptr);
67	vgaHWPtr hwp = VGAHWPTR(pCir->pScrn);
68
69	if (!AlpI2CSwitchToBus(b))
70		return;
71
72	reg = hwp->readSeq(hwp, 0x08);
73	*clock = (reg & 0x04) != 0;
74	*data  = (reg & 0x80) != 0;
75	/* ErrorF("AlpI2CGetBits: %d %d\n", *clock, *data); */
76}
77
78Bool
79AlpI2CInit(ScrnInfoPtr pScrn)
80{
81	CirPtr pCir = CIRPTR(pScrn);
82	I2CBusPtr I2CPtr;
83
84#ifdef ALP_DEBUG
85	ErrorF("AlpI2CInit\n");
86#endif
87
88	switch(pCir->Chipset) {
89	case PCI_CHIP_GD5446:
90	case PCI_CHIP_GD5480:
91		break;
92	default:
93		return FALSE;
94	}
95
96
97	I2CPtr = xf86CreateI2CBusRec();
98	if (!I2CPtr) return FALSE;
99
100	pCir->I2CPtr1 = I2CPtr;
101
102	I2CPtr->BusName    = "I2C bus 1";
103	I2CPtr->scrnIndex  = pScrn->scrnIndex;
104	I2CPtr->I2CPutBits = AlpI2CPutBits;
105	I2CPtr->I2CGetBits = AlpI2CGetBits;
106	I2CPtr->DriverPrivate.ptr = pCir;
107
108	if (!xf86I2CBusInit(I2CPtr))
109		return FALSE;
110
111	I2CPtr = xf86CreateI2CBusRec();
112	if (!I2CPtr) return FALSE;
113
114	pCir->I2CPtr2 = I2CPtr;
115
116	I2CPtr->BusName    = "I2C bus 2";
117	I2CPtr->scrnIndex  = pScrn->scrnIndex;
118	I2CPtr->I2CPutBits = AlpI2CPutBits;
119	I2CPtr->I2CGetBits = AlpI2CGetBits;
120	I2CPtr->DriverPrivate.ptr = pCir;
121
122	if (!xf86I2CBusInit(I2CPtr))
123		return FALSE;
124
125	return TRUE;
126}
127