ntoskrnl/inbv/inbvport.c

   1 /*
   2  * PROJECT:         ReactOS Kernel
   3  * LICENSE:         BSD - See COPYING.ARM in the top level directory
   4  * FILE:            ntoskrnl/inbv/inbvport.c
   5  * PURPOSE:         Serial Port Boot Driver for Headless Terminal Support
   6  * PROGRAMMERS:     ReactOS Portable Systems Group
   7  */
   8
   9 /* INCLUDES ******************************************************************/
  10
  11 #include <ntoskrnl.h>
  12 #include <debug.h>
  13
  14 /* GLOBALS *******************************************************************/
  15
  16 CPPORT Port[4] =
  17 {
  18         {NULL, 0, TRUE},
  19         {NULL, 0, TRUE},
  20         {NULL, 0, TRUE},
  21         {NULL, 0, TRUE}
  22 };
  23
  24 /* FUNCTIONS *****************************************************************/
  25
  26 VOID
  27 NTAPI
  28 InbvPortEnableFifo(
  29         IN ULONG PortId,
  30         IN BOOLEAN Enable
  31         )
  32 {
  33         /* Set FIFO as requested */
  34         CpEnableFifo(Port[PortId].Address, Enable);
  35 }
  36
  37 VOID
  38 NTAPI
  39 InbvPortPutByte(
  40         IN ULONG PortId,
  41         IN BOOLEAN Output
  42         )
  43 {
  44         /* Send the byte */
  45         CpPutByte(&Port[PortId], Output);
  46 }
  47
  48 VOID
  49 NTAPI
  50 InbvPortTerminate(
  51         IN ULONG PortId
  52         )
  53 {
  54         /* The port is now available */
  55         Port[PortId].Address = NULL;
  56 }
  57
  58 BOOLEAN
  59 NTAPI
  60 InbvPortInitialize(
  61         IN ULONG BaudRate,
  62         IN ULONG PortNumber,
  63         IN PUCHAR PortAddress,
  64         OUT PULONG PortId,
  65         IN BOOLEAN IsMMIODevice
  66         )
  67 {
  68         /* Not yet supported */
  69         ASSERT(IsMMIODevice == FALSE);
  70
  71         /* Set default baud rate */
  72     if (BaudRate == 0) BaudRate = 19200;
  73
  74         /* Check if port or address given */
  75         if (PortNumber)
  76         {
  77                 /* Pick correct address for port */
  78            if (!PortAddress)
  79                 {
  80             switch (PortNumber)
  81                         {
  82                                 case 1:
  83                                         PortAddress = (PUCHAR)0x3F8;
  84                                         break;
  85
  86                                 case 2:
  87                                         PortAddress = (PUCHAR)0x2F8;
  88                                         break;
  89
  90                                 case 3:
  91                                         PortAddress = (PUCHAR)0x3E8;
  92                                         break;
  93
  94                                 default:
  95                                         PortNumber = 4;
  96                                         PortAddress = (PUCHAR)0x2E8;
  97                         }
  98                 }
  99     }
 100         else
 101         {
 102                 /* Pick correct port for address */
 103                 PortAddress = (PUCHAR)0x2F8;
 104                 if (CpDoesPortExist(PortAddress))
 105                 {
 106                         PortNumber = 2;
 107         }
 108                 else
 109                 {
 110                         PortAddress = (PUCHAR)0x3F8;
 111                         if (!CpDoesPortExist(PortAddress)) return FALSE;
 112                         PortNumber = 1;
 113                 }
 114         }
 115
 116         /* Initialize the port unless it's already up, and then return it */
 117         if (Port[PortNumber - 1].Address) return FALSE;
 118         CpInitialize(&Port[PortNumber - 1], PortAddress, BaudRate);
 119         *PortId = PortNumber - 1;
 120         return TRUE;
 121 }