/* * sound/sb_dsp.c *  * The low level driver for the SoundBlaster DS chips. *  * Copyright by Hannu Savolainen 1993 *  * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are * met: 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. 2. * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. *  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. *  */#include "sound_config.h"#if defined(CONFIGURE_SOUNDCARD) && !defined(EXCLUDE_SB) && !defined(EXCLUDE_MIDI)#include "sb.h"#undef SB_TEST_IRQ/* * The DSP channel can be used either for input or output. Variable * 'sb_irq_mode' will be set when the program calls read or write first time * after open. Current version doesn't support mode changes without closing * and reopening the device. Support for this feature may be implemented in a * future version of this driver. */extern int      sb_dsp_ok;	/* Set to 1 after successful initialization */extern int      sb_midi_mode;extern int      sb_midi_busy;	/* 1 if the process has output to MIDI */extern int      sb_dsp_busy;extern int      sb_dsp_highspeed;extern volatile int sb_irq_mode;	/* IMODE_INPUT, IMODE_OUTPUT					 * or IMODE_NONE */extern int      sb_dsp_model;	/* 1=SB, 2=SB Pro */extern int      sb_duplex_midi;extern int      sb_intr_active;static intsb_midi_open (int dev, int mode,	      void            (*input) (int dev, unsigned char data),	      void            (*output) (int dev)){  int             ret;  if (!sb_dsp_ok)    {      printk ("SB Error: MIDI hardware not installed\n");      return RET_ERROR (ENXIO);    }  if (mode != OPEN_WRITE && !sb_duplex_midi)    {      if (num_midis == 1)	printk ("SoundBlaster: Midi input not currently supported\n");      return RET_ERROR (EPERM);    }  sb_midi_mode = NORMAL_MIDI;  if (mode != OPEN_WRITE)    {      if (sb_dsp_busy || sb_intr_active)	return RET_ERROR (EBUSY);      sb_midi_mode = UART_MIDI;    }  if (sb_dsp_highspeed)    {      printk ("SB Error: Midi output not possible during stereo or high speed audio\n");      return RET_ERROR (EBUSY);    }  if (sb_midi_mode == UART_MIDI)    {      sb_irq_mode = IMODE_MIDI;      sb_reset_dsp ();      if (!sb_dsp_command (0x35))	return RET_ERROR (EIO);	/* Enter the UART mode */      sb_intr_active = 1;      if ((ret = sb_get_irq ()) < 0)	{	  sb_reset_dsp ();	  return 0;		/* IRQ not free */	}    }  sb_midi_busy = 1;  return 0;}static voidsb_midi_close (int dev){  if (sb_midi_mode == UART_MIDI)    {      sb_reset_dsp ();		/* The only way to kill the UART mode */      sb_free_irq ();    }  sb_intr_active = 0;  sb_midi_busy = 0;}static intsb_midi_out (int dev, unsigned char midi_byte){  unsigned long   flags;  sb_midi_busy = 1;		/* Kill all notes after close */  if (sb_midi_mode == NORMAL_MIDI)    {      DISABLE_INTR (flags);      if (sb_dsp_command (0x38))	sb_dsp_command (midi_byte);      else	printk ("SB Error: Unable to send a MIDI byte\n");      RESTORE_INTR (flags);    }  else    sb_dsp_command (midi_byte);	/* UART write */  return 1;}static intsb_midi_start_read (int dev){  if (sb_midi_mode != UART_MIDI)    {      printk ("SoundBlaster: MIDI input not implemented.\n");      return RET_ERROR (EPERM);    }  return 0;}static intsb_midi_end_read (int dev){  if (sb_midi_mode == UART_MIDI)    {      sb_reset_dsp ();      sb_intr_active = 0;    }  return 0;}static intsb_midi_ioctl (int dev, unsigned cmd, unsigned arg){  return RET_ERROR (EPERM);}static struct midi_operations sb_midi_operations ={  {"SoundBlaster", 0, 0, SNDCARD_SB},  sb_midi_open,  sb_midi_close,  sb_midi_ioctl,  sb_midi_out,  sb_midi_start_read,  sb_midi_end_read,  NULL,				/* Kick */  NULL,				/* command */  NULL				/* buffer_status */};voidsb_midi_init(int model){  midi_devs[num_midis++] = &sb_midi_operations;}#endif