git.oblomov.eu Git - nouveau/blob - src/nv_i2c.c

   1
   2 #include "nv_include.h"
   3
   4 /*
   5  * DDC1 support only requires DDC_SDA_MASK,
   6  * DDC2 support requires DDC_SDA_MASK and DDC_SCL_MASK
   7  */
   8 #define DDC_SDA_READ_MASK  (1 << 3)
   9 #define DDC_SCL_READ_MASK  (1 << 2)
  10 #define DDC_SDA_WRITE_MASK (1 << 4)
  11 #define DDC_SCL_WRITE_MASK (1 << 5)
  12
  13 static void
  14 NVI2CGetBits(I2CBusPtr b, int *clock, int *data)
  15 {
  16         NVPtr pNv = NVPTR(xf86Screens[b->scrnIndex]);
  17         unsigned char val;
  18
  19         /* Get the result. */
  20         /* Doing this on head 0 seems fine. */
  21         val = NVReadVgaCrtc(pNv, 0, b->DriverPrivate.uval);
  22
  23         *clock = (val & DDC_SCL_READ_MASK) != 0;
  24         *data  = (val & DDC_SDA_READ_MASK) != 0;
  25 }
  26
  27 static void
  28 NVI2CPutBits(I2CBusPtr b, int clock, int data)
  29 {
  30         NVPtr pNv = NVPTR(xf86Screens[b->scrnIndex]);
  31         unsigned char val;
  32
  33         /* Doing this on head 0 seems fine. */
  34         val = NVReadVgaCrtc(pNv, 0, b->DriverPrivate.uval + 1) & 0xf0;
  35         if (clock)
  36                 val |= DDC_SCL_WRITE_MASK;
  37         else
  38                 val &= ~DDC_SCL_WRITE_MASK;
  39
  40         if (data)
  41                 val |= DDC_SDA_WRITE_MASK;
  42         else
  43                 val &= ~DDC_SDA_WRITE_MASK;
  44
  45         /* Doing this on head 0 seems fine. */
  46         NVWriteVgaCrtc(pNv, 0, b->DriverPrivate.uval + 1, val | 0x1);
  47 }
  48
  49 static void NV50_I2CPutBits(I2CBusPtr b, int clock, int data)
  50 {
  51         NVPtr pNv = NVPTR(xf86Screens[b->scrnIndex]);
  52
  53         NVWrite(pNv, NV50_I2C_PORT(b->DriverPrivate.val), (4 | clock | data << 1));
  54 }
  55
  56 static void NV50_I2CGetBits(I2CBusPtr b, int *clock, int *data)
  57 {
  58         NVPtr pNv = NVPTR(xf86Screens[b->scrnIndex]);
  59         unsigned char val;
  60
  61         val = NVRead(pNv, NV50_I2C_PORT(b->DriverPrivate.val));
  62         *clock = !!(val & 1);
  63         *data = !!(val & 2);
  64 }
  65
  66 Bool
  67 NV_I2CInit(ScrnInfoPtr pScrn, I2CBusPtr *bus_ptr, int i2c_reg, char *name)
  68 {
  69         I2CBusPtr pI2CBus;
  70         NVPtr pNv = NVPTR(pScrn);
  71
  72         pI2CBus = xf86CreateI2CBusRec();
  73         if(!pI2CBus)
  74                 return FALSE;
  75
  76         pI2CBus->BusName    = name;
  77         pI2CBus->scrnIndex  = pScrn->scrnIndex;
  78         if (pNv->Architecture == NV_ARCH_50) {
  79                 pI2CBus->I2CPutBits = NV50_I2CPutBits;
  80                 pI2CBus->I2CGetBits = NV50_I2CGetBits;
  81                 /* Could this be used for the rest as well? */
  82                 pI2CBus->ByteTimeout = 2200; /* VESA DDC spec 3 p. 43 (+10 %) */
  83                 pI2CBus->StartTimeout = 550;
  84                 pI2CBus->BitTimeout = 40;
  85                 pI2CBus->ByteTimeout = 40;
  86                 pI2CBus->AcknTimeout = 40;
  87         } else {
  88                 pI2CBus->I2CPutBits = NVI2CPutBits;
  89                 pI2CBus->I2CGetBits = NVI2CGetBits;
  90                 pI2CBus->AcknTimeout = 5;
  91         }
  92
  93         pI2CBus->DriverPrivate.uval = i2c_reg;
  94
  95         if (!xf86I2CBusInit(pI2CBus)) {
  96                 return FALSE;
  97         }
  98
  99         *bus_ptr = pI2CBus;
 100         return TRUE;
 101 }
 102