reactos/drivers/dd/sound/dsp.c

   1 /************************************
   2  * unsigned char read_dsp(void)
   3  *
   4  * Reads the DSP chip
   5  * Arguments: none
   6  * Returns: Byte read
   7  ************************************/
   8 unsigned char read_dsp(unsigned short base)
   9 {
  10         while((inb(base+0x0e)&0x80)==0);        //Wait until there is something to read
  11         return  inb(base+0x0a);
  12 }
  13
  14 /************************************'
  15  * sb_status detect_dsp(void);
  16  *
  17  * Detects if a SB16 is installed
  18  * Arguments: None
  19  * Returns: Success or failure
  20  ************************************/
  21 sb_status detect_dsp(SB16* sb16)
  22 {
  23         for(base=0x200;base<0x280;base+=0x10)   //Tries to reset all DSP addresses there is
  24                 if(reset_dsp(base)==SB_TRUE)
  25                 {
  26                         sb16->base=base;
  27                         return SB_TRUE;
  28                 }
  29         return SB_FALSE;
  30 }
  31
  32 /**************************************
  33  * sb_status reset_dsp(unsigned short base_address);
  34  *
  35  * Tries to reset a DSP chip
  36  * Arguments: base address
  37  * Returns: Success of failure
  38  **************************************/
  39 sb_status reset_dsp(unsigned short base_address)
  40 {
  41         int delay;
  42
  43         outb(base_address+DSP_RESET_PORT,1);
  44         for(delay=0;delay<0xffff;delay++);
  45
  46         outb(base_address+DSP_RESET_PORT,0);
  47         for(delay=0;delay<0xffff;delay++);
  48
  49         if((inb(base_address+DSP_READ_STATUS_PORT)&0x80)==0) return SB_FALSE;
  50
  51         if(inb(base_address+DSP_READ_DATA_PORT)!=0xAA) return SB_FALSE;
  52
  53         return SB_TRUE;
  54 }
  55
  56 void write_dsp(unsigned short base,unsigned char data)
  57 {
  58   while ((inb(base+DSP_WRITE_PORT) & 0x80) != 0);
  59   outb(base+DSP_WRITE_PORT, data);
  60 }
  61