ReactOS Development > Doxygen

00001 /*
00002     ReactOS Sound System
00003     Sound Blaster DSP support
00004     Sample rate routines
00005 
00006     Author:
00007         Andrew Greenwood (silverblade@reactos.org)
00008 
00009     History:
00010         2 July 2008 - Created (split from sbdsp.c)
00011 
00012     Notes:
00013         Functions documented in sbdsp.h
00014 */
00015 
00016 #include "precomp.h"
00017 
00018 BOOLEAN
00019 SbDspIsValidInputRate(
00020     IN  UCHAR MajorVersion,
00021     IN  UCHAR MinorVersion,
00022     IN  USHORT Rate,
00023     IN  BOOLEAN Stereo)
00024 {
00025     if ( MajorVersion == 1 )
00026     {
00027         if ( Stereo )
00028             return FALSE;
00029 
00030         return ( ( Rate >= 4000 ) && ( Rate <= 13000 ) );
00031     }
00032     else if ( MajorVersion == 2 )
00033     {
00034         if ( Stereo )
00035             return FALSE;
00036 
00037         if ( MinorVersion == 0 )
00038             return ( ( Rate >= 4000 ) && ( Rate <= 15000 ) );
00039         else
00040             return ( ( Rate >= 4000 ) && ( Rate <= 44100 ) );
00041     }
00042     else if ( MajorVersion == 3 )
00043     {
00044         if ( Stereo )
00045             return FALSE;
00046 
00047         return ( ( Rate >= 4000 ) && ( Rate <= 13000 ) );
00048     }
00049     else /* 4.00 and above */
00050     {
00051         return ( ( Rate >= 5000 ) && ( Rate <= 44100 ) );
00052     }
00053 }
00054 
00055 BOOLEAN
00056 SbDspIsValidOutputRate(
00057     IN  UCHAR MajorVersion,
00058     IN  UCHAR MinorVersion,
00059     IN  USHORT Rate,
00060     IN  BOOLEAN Stereo)
00061 {
00062     if ( MajorVersion == 1 )
00063     {
00064         if ( Stereo )
00065             return FALSE;
00066 
00067         return ( ( Rate >= 4000 ) && ( Rate <= 23000 ) );
00068     }
00069     else if ( MajorVersion == 2 )
00070     {
00071         if ( Stereo )
00072             return FALSE;
00073 
00074         if ( MinorVersion == 0 )
00075             return ( ( Rate >= 4000 ) && ( Rate <= 23000 ) );
00076         else
00077             return ( ( Rate >= 4000 ) && ( Rate <= 44100 ) );
00078     }
00079     else if ( MajorVersion == 3 )
00080     {
00081         if ( ! Stereo )
00082             return ( ( Rate >= 4000 ) && ( Rate <= 44100 ) );
00083         else
00084             return ( ( Rate >= 11025 ) && ( Rate <= 22050 ) );
00085     }
00086     else /* 4.00 and above */
00087     {
00088         return ( ( Rate >= 5000 ) && ( Rate <= 44100 ) );
00089     }
00090 }
00091 
00092 /* Internal routine - call only after submitting one of the rate commands */
00093 NTSTATUS
00094 SbDsp4WriteRate(
00095     IN  PUCHAR BasePort,
00096     IN  USHORT Rate,
00097     IN  ULONG Timeout)
00098 {
00099     NTSTATUS Status;
00100 
00101     /* NOTE - No check for validity of rate! */
00102 
00103     /* Write high byte */
00104     Status = SbDspWrite(BasePort, (Rate & 0xff00) >> 8, Timeout);
00105     if ( Status != STATUS_SUCCESS )
00106         return Status;
00107 
00108     /* Write low byte */
00109     Status = SbDspWrite(BasePort, Rate & 0xff, Timeout);
00110     if ( Status != STATUS_SUCCESS )
00111         return Status;
00112 
00113     return Status;
00114 }
00115 
00116 NTSTATUS
00117 SbDsp4SetOutputRate(
00118     IN  PUCHAR BasePort,
00119     IN  USHORT Rate,
00120     IN  ULONG Timeout)
00121 {
00122     NTSTATUS Status;
00123 
00124     /* NOTE - No check for validity of rate! */
00125 
00126     /* Prepare to write the output rate */
00127     Status = SbDspWrite(BasePort, SB_DSP_OUTPUT_RATE, (Rate & 0xff00) >> 8);
00128     if ( Status != STATUS_SUCCESS )
00129         return Status;
00130 
00131     return SbDsp4WriteRate(BasePort, Rate, Timeout);
00132 }
00133 
00134 NTSTATUS
00135 SbDsp4SetInputRate(
00136     IN  PUCHAR BasePort,
00137     IN  USHORT Rate,
00138     IN  ULONG Timeout)
00139 {
00140     NTSTATUS Status;
00141 
00142     /* NOTE - No check for validity of rate! */
00143 
00144     /* Prepare to write the input rate */
00145     Status = SbDspWrite(BasePort, SB_DSP_OUTPUT_RATE, (Rate & 0xff00) >> 8);
00146     if ( Status != STATUS_SUCCESS )
00147         return Status;
00148 
00149     return SbDsp4WriteRate(BasePort, Rate, Timeout);
00150 }
00151
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