staging: comedi: ni_labpc_isadma: new module for ISA DMA support

It's just an empty module at the moment, selected by COMEDI_NI_LABPC_ISA
&& ISA_DMA_API && VIRT_TO_BUS, but will be populated by later patches to
migrate ISA DMA support for NI Lab-PC cards out of the "ni_labpc"
module.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/Kconfig

@@ -492,6 +492,7 @@ config COMEDI_NI_ATMIO16D
 config COMEDI_NI_LABPC_ISA
 	tristate "NI Lab-PC and compatibles ISA support"
 	select COMEDI_NI_LABPC
+	select COMEDI_NI_LABPC_ISADMA if ISA_DMA_API && VIRT_TO_BUS
 	depends on VIRT_TO_BUS
 	---help---
 	  Enable support for National Instruments Lab-PC and compatibles
@@ -1272,6 +1273,9 @@ config COMEDI_NI_LABPC
 	select COMEDI_8255
 	select COMEDI_FC
 
+config COMEDI_NI_LABPC_ISADMA
+	tristate
+
 config COMEDI_NI_TIO
 	tristate
 

drivers/staging/comedi/drivers/Makefile

@@ -132,6 +132,7 @@ obj-$(CONFIG_COMEDI_MITE)		+= mite.o
 obj-$(CONFIG_COMEDI_NI_TIO)		+= ni_tio.o
 obj-$(CONFIG_COMEDI_NI_TIOCMD)		+= ni_tiocmd.o
 obj-$(CONFIG_COMEDI_NI_LABPC)		+= ni_labpc.o
+obj-$(CONFIG_COMEDI_NI_LABPC_ISADMA)	+= ni_labpc_isadma.o
 
 obj-$(CONFIG_COMEDI_8255)		+= 8255.o
 obj-$(CONFIG_COMEDI_AMPLC_DIO200)	+= amplc_dio200_common.o

drivers/staging/comedi/drivers/ni_labpc.c

@@ -71,6 +71,7 @@
 #include "8255.h"
 #include "comedi_fc.h"
 #include "ni_labpc.h"
+#include "ni_labpc_isadma.h"
 
 /*
  * Register map (all registers are 8-bit)

drivers/staging/comedi/drivers/ni_labpc_isadma.c

@@ -0,0 +1,37 @@
+/*
+ * comedi/drivers/ni_labpc_isadma.c
+ * ISA DMA support for National Instruments Lab-PC series boards and
+ * compatibles.
+ *
+ * Extracted from ni_labpc.c:
+ * Copyright (C) 2001-2003 Frank Mori Hess <fmhess@users.sourceforge.net>
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+
+#include "ni_labpc_isadma.h"
+
+static int __init ni_labpc_isadma_init_module(void)
+{
+	return 0;
+}
+module_init(ni_labpc_isadma_init_module);
+
+static void __exit ni_labpc_isadma_cleanup_module(void)
+{
+}
+module_exit(ni_labpc_isadma_cleanup_module);
+
+MODULE_AUTHOR("Comedi http://www.comedi.org");
+MODULE_DESCRIPTION("Comedi NI Lab-PC ISA DMA support");
+MODULE_LICENSE("GPL");

drivers/staging/comedi/drivers/ni_labpc_isadma.h

@@ -0,0 +1,16 @@
+/*
+ * ni_labpc ISA DMA support.
+*/
+
+#ifndef _NI_LABPC_ISADMA_H
+#define _NI_LABPC_ISADMA_H
+
+#define NI_LABPC_HAVE_ISA_DMA	IS_ENABLED(CONFIG_COMEDI_NI_LABPC_ISADMA)
+
+#if NI_LABPC_HAVE_ISA_DMA
+
+#else
+
+#endif
+
+#endif /* _NI_LABPC_ISADMA_H */