Add OPL lib plumbing and Linux native driver.

Subversion-branch: /branches/opl-branch
Subversion-revision: 1458

4 files changed, 228 insertions, 7 deletions

diff --git a/opl/Makefile.am b/opl/Makefile.am
index 65f8b2de..e1dbe42c 100644
--- a/opl/Makefile.am
+++ b/opl/Makefile.am
@@ -4,6 +4,8 @@ AM_CFLAGS=@SDLMIXER_CFLAGS@
 noinst_LIBRARIES=libopl.a
 
 libopl_a_SOURCES =                                \
+                            opl_internal.h        \
         opl.c               opl.h                 \
-        fmopl.c
+        opl_linux.c                               \
+        fmopl.c             fmopl.h
 
diff --git a/opl/opl.c b/opl/opl.c
index d3dfc23b..28609223 100644
--- a/opl/opl.c
+++ b/opl/opl.c
@@ -23,27 +23,71 @@
 //
 //-----------------------------------------------------------------------------
 
+#include "config.h"
+
+#include <stdlib.h>
+
 #include "opl.h"
+#include "opl_internal.h"
+
+#ifdef HAVE_IOPERM
+extern opl_driver_t opl_linux_driver;
+#endif
+
+static opl_driver_t *drivers[] =
+{
+#ifdef HAVE_IOPERM
+    &opl_linux_driver,
+#endif
+    NULL
+};
+
+static opl_driver_t *driver = NULL;
 
 int OPL_Init(unsigned int port_base)
 {
-    // TODO
-    return 1;
+    int i;
+
+    // Try drivers until we find a working one:
+
+    for (i=0; drivers[i] != NULL; ++i)
+    {
+        if (drivers[i]->init_func(port_base))
+        {
+            driver = drivers[i];
+            return 1;
+        }
+    }
+
+    return 0;
 }
 
 void OPL_Shutdown(void)
 {
-    // TODO
+    if (driver != NULL)
+    {
+        driver->shutdown_func();
+        driver = NULL;
+    }
 }
 
 void OPL_WritePort(opl_port_t port, unsigned int value)
 {
-    // TODO
+    if (driver != NULL)
+    {
+        driver->write_port_func(port, value);
+    }
 }
 
 unsigned int OPL_ReadPort(opl_port_t port)
 {
-    // TODO
-    return 0;
+    if (driver != NULL)
+    {
+        return driver->read_port_func(port);
+    }
+    else
+    {
+        return 0;
+    }
 }
 
diff --git a/opl/opl_internal.h b/opl/opl_internal.h
new file mode 100644
index 00000000..964f55cc
--- /dev/null
+++ b/opl/opl_internal.h
@@ -0,0 +1,96 @@
+// Emacs style mode select   -*- C++ -*- 
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2009 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.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+//
+// DESCRIPTION:
+//     OPL internal interface.
+//
+//-----------------------------------------------------------------------------
+
+
+#ifndef OPL_INTERNAL_H
+#define OPL_INTERNAL_H
+
+#include "opl.h"
+
+typedef int (*opl_init_func)(unsigned int port_base);
+typedef void (*opl_shutdown_func)(void);
+typedef unsigned int (*opl_read_port_func)(opl_port_t port);
+typedef void (*opl_write_port_func)(opl_port_t port, unsigned int value);
+
+typedef struct
+{
+    char *name;
+
+    opl_init_func init_func;
+    opl_shutdown_func shutdown_func;
+    opl_read_port_func read_port_func;
+    opl_write_port_func write_port_func;
+} opl_driver_t;
+
+#endif /* #ifndef OPL_INTERNAL_H */
+
+// Emacs style mode select   -*- C++ -*- 
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2009 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.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+//
+// DESCRIPTION:
+//     OPL internal interface.
+//
+//-----------------------------------------------------------------------------
+
+
+#ifndef OPL_INTERNAL_H
+#define OPL_INTERNAL_H
+
+#include "opl.h"
+
+typedef int (*opl_init_func)(unsigned int port_base);
+typedef void (*opl_shutdown_func)(void);
+typedef unsigned int (*opl_read_port_func)(opl_port_t port);
+typedef void (*opl_write_port_func)(opl_port_t port, unsigned int value);
+
+typedef struct
+{
+    char *name;
+
+    opl_init_func init_func;
+    opl_shutdown_func shutdown_func;
+    opl_read_port_func read_port_func;
+    opl_write_port_func write_port_func;
+} opl_driver_t;
+
+#endif /* #ifndef OPL_INTERNAL_H */
+
diff --git a/opl/opl_linux.c b/opl/opl_linux.c
new file mode 100644
index 00000000..438b091a
--- /dev/null
+++ b/opl/opl_linux.c
@@ -0,0 +1,79 @@
+// Emacs style mode select   -*- C++ -*- 
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2009 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.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+//
+// DESCRIPTION:
+//     OPL Linux interface.
+//
+//-----------------------------------------------------------------------------
+
+#include "config.h"
+
+#ifdef HAVE_IOPERM
+
+#include <unistd.h>
+#include <sys/io.h>
+
+#include "opl.h"
+#include "opl_internal.h"
+
+static unsigned int opl_port_base;
+
+static void OPL_Linux_Init(unsigned int port_base)
+{
+    // Try to get permissions:
+
+    if (ioperm(port_base, 2, 1) < 0)
+    {
+        return 0;
+    }
+
+    opl_port_base = port_base;
+
+    return 1;
+}
+
+static void OPL_Linux_Shutdown(void)
+{
+    // 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(opl_port_base + port, value);
+}
+
+opl_driver_t opl_linux_driver =
+{
+    "Linux",
+    OPL_Linux_Init,
+    OPL_Linux_Shutdown,
+    OPL_Linux_PortRead,
+    OPL_Linux_PortWrite
+};
+
+#endif /* #ifdef HAVE_IOPERM */
+