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chocolate-doom-wii/opl/opl_linux.c
2016-10-30 18:40:00 -04:00

104 lines
2.2 KiB
C

//
// Copyright(C) 2005-2014 Simon Howard
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// DESCRIPTION:
// OPL Linux interface.
//
#include "config.h"
#ifdef HAVE_IOPERM
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/io.h>
#include "opl.h"
#include "opl_internal.h"
#include "opl_timer.h"
static unsigned int opl_port_base;
static int OPL_Linux_Init(unsigned int port_base)
{
// Try to get permissions:
if (ioperm(port_base, 2, 1) < 0)
{
fprintf(stderr, "Failed to get I/O port permissions for 0x%x: %s\n",
port_base, strerror(errno));
if (errno == EPERM)
{
fprintf(stderr,
"\tYou may need to run the program as root in order\n"
"\tto acquire I/O port permissions for OPL MIDI playback.\n");
}
return 0;
}
opl_port_base = port_base;
// Start callback thread
if (!OPL_Timer_StartThread())
{
ioperm(port_base, 2, 0);
return 0;
}
return 1;
}
static void OPL_Linux_Shutdown(void)
{
// Stop callback thread
OPL_Timer_StopThread();
// Release permissions
ioperm(opl_port_base, 2, 0);
}
static unsigned int OPL_Linux_PortRead(opl_port_t port)
{
return inb(opl_port_base + port);
}
static void OPL_Linux_PortWrite(opl_port_t port, unsigned int value)
{
outb(value, opl_port_base + port);
}
opl_driver_t opl_linux_driver =
{
"Linux",
OPL_Linux_Init,
OPL_Linux_Shutdown,
OPL_Linux_PortRead,
OPL_Linux_PortWrite,
OPL_Timer_SetCallback,
OPL_Timer_ClearCallbacks,
OPL_Timer_Lock,
OPL_Timer_Unlock,
OPL_Timer_SetPaused,
OPL_Timer_AdjustCallbacks,
};
#endif /* #ifdef HAVE_IOPERM */