comedi_fc.h revision a9f23e00c17567cc4b7ce50cd07226f7bfb70da6 
1/*
2    comedi_fc.h
3
4    This is a place for code driver writers wish to share between
5    two or more drivers. These functions are meant to be used only
6    by drivers, they are NOT part of the kcomedilib API!
7
8    Author:  Frank Mori Hess <fmhess@users.sourceforge.net>
9    Copyright (C) 2002 Frank Mori Hess
10
11    This program is free software; you can redistribute it and/or modify
12    it under the terms of the GNU General Public License as published by
13    the Free Software Foundation; either version 2 of the License, or
14    (at your option) any later version.
15
16    This program is distributed in the hope that it will be useful,
17    but WITHOUT ANY WARRANTY; without even the implied warranty of
18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19    GNU General Public License for more details.
20
21    You should have received a copy of the GNU General Public License
22    along with this program; if not, write to the Free Software
23    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24
25************************************************************************/
26
27#ifndef _COMEDI_FC_H
28#define _COMEDI_FC_H
29
30#include "../comedidev.h"
31
32/* Writes an array of data points to comedi's buffer */
33extern unsigned int cfc_write_array_to_buffer(comedi_subdevice * subd,
34	void *data, unsigned int num_bytes);
35
36static inline unsigned int cfc_write_to_buffer(comedi_subdevice * subd,
37	sampl_t data)
38{
39	return cfc_write_array_to_buffer(subd, &data, sizeof(data));
40};
41
42static inline unsigned int cfc_write_long_to_buffer(comedi_subdevice * subd,
43	lsampl_t data)
44{
45	return cfc_write_array_to_buffer(subd, &data, sizeof(data));
46};
47
48extern unsigned int cfc_read_array_from_buffer(comedi_subdevice * subd,
49	void *data, unsigned int num_bytes);
50
51extern unsigned int cfc_handle_events(comedi_device * dev,
52	comedi_subdevice * subd);
53
54static inline unsigned int cfc_bytes_per_scan(comedi_subdevice * subd)
55{
56	int num_samples;
57	int bits_per_sample;
58
59	switch (subd->type) {
60	case COMEDI_SUBD_DI:
61	case COMEDI_SUBD_DO:
62	case COMEDI_SUBD_DIO:
63		bits_per_sample = 8 * bytes_per_sample(subd);
64		num_samples =
65			(subd->async->cmd.chanlist_len + bits_per_sample -
66			1) / bits_per_sample;
67		break;
68	default:
69		num_samples = subd->async->cmd.chanlist_len;
70		break;
71	}
72	return num_samples * bytes_per_sample(subd);
73}
74
75#endif /* _COMEDI_FC_H */
76