dev_table.c

LINUX1.0内核源代码,学习LINUX编程的一定要看。

/*
 * sound/dev_table.c
 * 
 * Device call tables.
 * 
 * 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.
 * 
 */

#define _DEV_TABLE_C_
#include "sound_config.h"

#ifdef CONFIGURE_SOUNDCARD

long
sndtable_init (long mem_start)
{
  int             i, n = sizeof (supported_drivers) / sizeof (struct card_info);

  for (i = 0; i < (n - 1); i++)
    if (supported_drivers[i].enabled)
    if (supported_drivers[i].probe (&supported_drivers[i].config))
      {
#ifndef SHORT_BANNERS
	printk ("snd%d",
		supported_drivers[i].card_type);
#endif

	mem_start = supported_drivers[i].attach (mem_start, &supported_drivers[i].config);
#ifndef SHORT_BANNERS
	printk (" at 0x%x irq %d drq %d\n",
		supported_drivers[i].config.io_base,
		supported_drivers[i].config.irq,
		supported_drivers[i].config.dma);
#endif
      }
    else
      supported_drivers[i].enabled=0;	/* Mark as not detected */
  return mem_start;
}

int
sndtable_probe (int unit, struct address_info *hw_config)
{
  int             i, n = sizeof (supported_drivers) / sizeof (struct card_info);

  if (!unit)
    return TRUE;

  for (i = 0; i < (n - 1); i++)
    if (supported_drivers[i].card_type == unit)
    {
	supported_drivers[i].config.io_base = hw_config->io_base;
	supported_drivers[i].config.irq = hw_config->irq;
	supported_drivers[i].config.dma = hw_config->dma;
        if (supported_drivers[i].probe (hw_config)) return 1;
        supported_drivers[i].enabled=0;	/* Mark as not detected */
        return 0;
    }

  return FALSE;
}

int
sndtable_init_card (int unit, struct address_info *hw_config)
{
  int             i, n = sizeof (supported_drivers) / sizeof (struct card_info);

  if (!unit)
    {
      if (sndtable_init (0) != 0)
	panic ("snd: Invalid memory allocation\n");
      return TRUE;
    }

  for (i = 0; i < (n - 1); i++)
    if (supported_drivers[i].card_type == unit)
      {
	supported_drivers[i].config.io_base = hw_config->io_base;
	supported_drivers[i].config.irq = hw_config->irq;
	supported_drivers[i].config.dma = hw_config->dma;

	if (supported_drivers[i].attach (0, hw_config) != 0)
	  panic ("snd#: Invalid memory allocation\n");
	return TRUE;
      }

  return FALSE;
}

int
sndtable_get_cardcount (void)
{
  return num_dspdevs + num_mixers + num_synths + num_midis;
}

#ifdef linux
void sound_setup(char *str, int *ints)
{
  int             i, n = sizeof (supported_drivers) / sizeof (struct card_info);

/*
 * First disable all drivers
 */

	for (i=0;i<n;i++)
		supported_drivers[i].enabled = 0;

	if (ints[0] == 0 || ints[1] == 0) return;
/*
 * Then enable them one by time
 */

 	for (i=1;i<=ints[0];i++)
 	{
 		int card_type, ioaddr, irq, dma, ptr, j;
 		unsigned int val;

		val = (unsigned int)ints[i];

		card_type = (val & 0x0ff00000) >> 20;

		if (card_type > 127)
		{
			/* Add any future extensions here*/
			return;
		}

		ioaddr	  = (val & 0x000fff00) >> 8;
		irq	  = (val & 0x000000f0) >> 4;
		dma 	  = (val & 0x0000000f);

		ptr = -1;
		for (j=0;j<n && ptr == -1;j++)
		if (supported_drivers[j].card_type == card_type)
			ptr = j;

	 	if (ptr == -1)
	 	   printk("Sound: Invalid setup parameter 0x%08x\n", val);
	 	else
	 	{
	 		supported_drivers[ptr].enabled = 1;
	 		supported_drivers[ptr].config.io_base = ioaddr;
	 		supported_drivers[ptr].config.irq = irq;
	 		supported_drivers[ptr].config.dma = dma;
	 	}
 	}
}
#else
void sound_chconf(int card_type, int ioaddr, int irq, int dma)
{
  int             i, n = sizeof (supported_drivers) / sizeof (struct card_info);

 		int ptr, j;

		ptr = -1;
		for (j=0;j<n && ptr == -1;j++)
		if (supported_drivers[j].card_type == card_type)
			ptr = j;

	 	if (ptr != -1)
	 	{
	 		supported_drivers[ptr].enabled = 1;
	 		if (ioaddr) supported_drivers[ptr].config.io_base = ioaddr;
	 		if (irq) supported_drivers[ptr].config.irq = irq;
	 		if (dma) supported_drivers[ptr].config.dma = dma;
	 	}
}
#endif

struct address_info *sound_getconf(int card_type)
{
	int j, ptr;
        int n = sizeof (supported_drivers) / sizeof (struct card_info);

	ptr = -1;
	for (j=0;j<n && ptr == -1;j++)
	if (supported_drivers[j].card_type == card_type)
		ptr = j;

 	if (ptr == -1) return (struct address_info *)NULL;

	return &supported_drivers[ptr].config;
}
#endif