1 files changed, 118 insertions, 0 deletions
diff --git a/drivers/staging/comedi/drivers/comedi_fc.c b/drivers/staging/comedi/drivers/comedi_fc.c
new file mode 100644
index 000000000000..cd74dbe5417d
--- /dev/null
+++ b/drivers/staging/comedi/drivers/comedi_fc.c
@@ -0,0 +1,118 @@
+/*
+    comedi/drivers/comedi_fc.c
+
+    This is a place for code driver writers wish to share between
+    two or more drivers.  fc is short
+    for frank-common.
+
+    Author:  Frank Mori Hess <fmhess@users.sourceforge.net>
+    Copyright (C) 2002 Frank Mori Hess
+
+    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., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+************************************************************************/
+
+#include "../comedidev.h"
+
+#include "comedi_fc.h"
+
+static void increment_scan_progress(comedi_subdevice *subd,
+				    unsigned int num_bytes)
+{
+	comedi_async *async = subd->async;
+	unsigned int scan_length = cfc_bytes_per_scan(subd);
+
+	async->scan_progress += num_bytes;
+	if (async->scan_progress >= scan_length) {
+		async->scan_progress %= scan_length;
+		async->events |= COMEDI_CB_EOS;
+	}
+}
+
+/* Writes an array of data points to comedi's buffer */
+unsigned int cfc_write_array_to_buffer(comedi_subdevice *subd, void *data,
+				       unsigned int num_bytes)
+{
+	comedi_async *async = subd->async;
+	unsigned int retval;
+
+	if (num_bytes == 0)
+		return 0;
+
+	retval = comedi_buf_write_alloc(async, num_bytes);
+	if (retval != num_bytes) {
+		rt_printk("comedi: buffer overrun\n");
+		async->events |= COMEDI_CB_OVERFLOW;
+		return 0;
+	}
+
+	comedi_buf_memcpy_to(async, 0, data, num_bytes);
+	comedi_buf_write_free(async, num_bytes);
+	increment_scan_progress(subd, num_bytes);
+	async->events |= COMEDI_CB_BLOCK;
+
+	return num_bytes;
+}
+EXPORT_SYMBOL(cfc_write_array_to_buffer);
+
+unsigned int cfc_read_array_from_buffer(comedi_subdevice *subd, void *data,
+					unsigned int num_bytes)
+{
+	comedi_async *async = subd->async;
+
+	if (num_bytes == 0)
+		return 0;
+
+	num_bytes = comedi_buf_read_alloc(async, num_bytes);
+	comedi_buf_memcpy_from(async, 0, data, num_bytes);
+	comedi_buf_read_free(async, num_bytes);
+	increment_scan_progress(subd, num_bytes);
+	async->events |= COMEDI_CB_BLOCK;
+
+	return num_bytes;
+}
+EXPORT_SYMBOL(cfc_read_array_from_buffer);
+
+unsigned int cfc_handle_events(comedi_device *dev, comedi_subdevice *subd)
+{
+	unsigned int events = subd->async->events;
+
+	if (events == 0)
+		return events;
+
+	if (events & (COMEDI_CB_EOA | COMEDI_CB_ERROR | COMEDI_CB_OVERFLOW))
+		subd->cancel(dev, subd);
+
+	comedi_event(dev, subd);
+
+	return events;
+}
+EXPORT_SYMBOL(cfc_handle_events);
+
+MODULE_AUTHOR("Frank Mori Hess <fmhess@users.sourceforge.net>");
+MODULE_DESCRIPTION("Shared functions for Comedi low-level drivers");
+MODULE_LICENSE("GPL");
+
+static int __init comedi_fc_init_module(void)
+{
+	return 0;
+}
+
+static void __exit comedi_fc_cleanup_module(void)
+{
+}
+
+module_init(comedi_fc_init_module);
+module_exit(comedi_fc_cleanup_module);