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comedi_fc.h
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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 <[email protected]>
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 */
33 extern unsigned int cfc_write_array_to_buffer(struct comedi_subdevice *subd,
34  void *data,
35  unsigned int num_bytes);
36 
37 static inline unsigned int cfc_write_to_buffer(struct comedi_subdevice *subd,
38  short data)
39 {
40  return cfc_write_array_to_buffer(subd, &data, sizeof(data));
41 };
42 
43 static inline unsigned int cfc_write_long_to_buffer(struct comedi_subdevice
44  *subd, unsigned int data)
45 {
46  return cfc_write_array_to_buffer(subd, &data, sizeof(data));
47 };
48 
49 extern unsigned int cfc_read_array_from_buffer(struct comedi_subdevice *subd,
50  void *data,
51  unsigned int num_bytes);
52 
53 extern unsigned int cfc_handle_events(struct comedi_device *dev,
54  struct comedi_subdevice *subd);
55 
56 static inline unsigned int cfc_bytes_per_scan(struct comedi_subdevice *subd)
57 {
58  int num_samples;
59  int bits_per_sample;
60 
61  switch (subd->type) {
62  case COMEDI_SUBD_DI:
63  case COMEDI_SUBD_DO:
64  case COMEDI_SUBD_DIO:
65  bits_per_sample = 8 * bytes_per_sample(subd);
66  num_samples = (subd->async->cmd.chanlist_len +
67  bits_per_sample - 1) / bits_per_sample;
68  break;
69  default:
70  num_samples = subd->async->cmd.chanlist_len;
71  break;
72  }
73  return num_samples * bytes_per_sample(subd);
74 }
75 
86 static inline int cfc_check_trigger_src(unsigned int *src, unsigned int flags)
87 {
88  unsigned int orig_src = *src;
89 
90  *src = orig_src & flags;
91  if (*src == TRIG_INVALID || *src != orig_src)
92  return -EINVAL;
93  return 0;
94 }
95 
100 static inline int cfc_check_trigger_is_unique(unsigned int src)
101 {
102  /* this test is true if more than one _src bit is set */
103  if ((src & (src - 1)) != 0)
104  return -EINVAL;
105  return 0;
106 }
107 
108 #endif /* _COMEDI_FC_H */