reactos/lib/drivers/sound/uartmidi/midiuart.c

   1 /*
   2     ReactOS Sound System
   3     MIDI UART support
   4
   5     Author:
   6         Andrew Greenwood (silverblade@reactos.org)
   7
   8     History:
   9         26 May 2008 - Created
  10
  11     Notes:
  12         Functions documented in midiuart.h
  13 */
  14
  15 #include <ntddk.h>
  16 #include "midiuart.h"
  17
  18 BOOLEAN
  19 WaitForMidiUartStatus(
  20     IN  PUCHAR UartBasePort,
  21     IN  UCHAR StatusFlags,
  22     IN  ULONG Timeout)
  23 {
  24     ULONG RemainingTime = Timeout;
  25
  26     while ( RemainingTime -- )
  27     {
  28         if ( READ_MIDIUART_STATUS(UartBasePort) & StatusFlags )
  29         {
  30             return TRUE;
  31         }
  32     }
  33
  34     return FALSE;
  35 }
  36
  37 BOOLEAN
  38 WriteMidiUartByte(
  39     IN  PUCHAR UartBasePort,
  40     IN  UCHAR Data,
  41     IN  ULONG Timeout)
  42 {
  43     if ( ! WaitForMidiUartCTS(UartBasePort, Timeout) )
  44     {
  45         return FALSE;
  46     }
  47
  48     WRITE_MIDIUART_DATA(UartBasePort, Data);
  49
  50     return TRUE;
  51 }
  52
  53 BOOLEAN
  54 WriteMidiUartMulti(
  55     IN  PUCHAR UartBasePort,
  56     IN  PUCHAR Data,
  57     IN  ULONG DataLength,
  58     IN  ULONG Timeout)
  59 {
  60     ULONG DataIndex;
  61
  62     for ( DataIndex = 0; DataIndex < DataLength; ++ DataIndex )
  63     {
  64         if ( ! WriteMidiUartByte(UartBasePort, Data[DataIndex], Timeout) )
  65         {
  66             /* We failed - don't try writing any more */
  67             return FALSE;
  68         }
  69     }
  70
  71     return TRUE;
  72 }
  73
  74 BOOLEAN
  75 ReadMidiUartByte(
  76     IN  PUCHAR UartBasePort,
  77     OUT UCHAR* Data,
  78     IN  ULONG Timeout)
  79 {
  80     if ( ! Data )
  81     {
  82         return FALSE;
  83     }
  84
  85     if ( ! WaitForMidiUartDTR(UartBasePort, Timeout) )
  86     {
  87         return FALSE;
  88     }
  89
  90     *Data = READ_MIDIUART_DATA(UartBasePort);
  91
  92     return TRUE;
  93 }