drivers/staging/comedi/kcomedilib/data.c

   1 /*
   2     kcomedilib/data.c
   3     implements comedi_data_*() functions
   4
   5     COMEDI - Linux Control and Measurement Device Interface
   6     Copyright (C) 2000 David A. Schleef <ds@schleef.org>
   7
   8     This program is free software; you can redistribute it and/or modify
   9     it under the terms of the GNU General Public License as published by
  10     the Free Software Foundation; either version 2 of the License, or
  11     (at your option) any later version.
  12
  13     This program is distributed in the hope that it will be useful,
  14     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16     GNU General Public License for more details.
  17
  18     You should have received a copy of the GNU General Public License
  19     along with this program; if not, write to the Free Software
  20     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21
  22 */
  23
  24 #include "../comedi.h"
  25 #include "../comedilib.h"
  26 #include "../comedidev.h"       /* for comedi_udelay() */
  27
  28 #include <linux/string.h>
  29
  30 int comedi_data_write(void *dev, unsigned int subdev, unsigned int chan,
  31         unsigned int range, unsigned int aref, unsigned int data)
  32 {
  33         struct comedi_insn insn;
  34
  35         memset(&insn, 0, sizeof(insn));
  36         insn.insn = INSN_WRITE;
  37         insn.n = 1;
  38         insn.data = &data;
  39         insn.subdev = subdev;
  40         insn.chanspec = CR_PACK(chan, range, aref);
  41
  42         return comedi_do_insn(dev, &insn);
  43 }
  44
  45 int comedi_data_read(void *dev, unsigned int subdev, unsigned int chan,
  46         unsigned int range, unsigned int aref, unsigned int *data)
  47 {
  48         struct comedi_insn insn;
  49
  50         memset(&insn, 0, sizeof(insn));
  51         insn.insn = INSN_READ;
  52         insn.n = 1;
  53         insn.data = data;
  54         insn.subdev = subdev;
  55         insn.chanspec = CR_PACK(chan, range, aref);
  56
  57         return comedi_do_insn(dev, &insn);
  58 }
  59
  60 int comedi_data_read_hint(void *dev, unsigned int subdev,
  61         unsigned int chan, unsigned int range, unsigned int aref)
  62 {
  63         struct comedi_insn insn;
  64         unsigned int dummy_data;
  65
  66         memset(&insn, 0, sizeof(insn));
  67         insn.insn = INSN_READ;
  68         insn.n = 0;
  69         insn.data = &dummy_data;
  70         insn.subdev = subdev;
  71         insn.chanspec = CR_PACK(chan, range, aref);
  72
  73         return comedi_do_insn(dev, &insn);
  74 }
  75
  76 int comedi_data_read_delayed(void *dev, unsigned int subdev,
  77         unsigned int chan, unsigned int range, unsigned int aref,
  78         unsigned int *data, unsigned int nano_sec)
  79 {
  80         int retval;
  81
  82         retval = comedi_data_read_hint(dev, subdev, chan, range, aref);
  83         if (retval < 0)
  84                 return retval;
  85
  86         comedi_udelay((nano_sec + 999) / 1000);
  87
  88         return comedi_data_read(dev, subdev, chan, range, aref, data);
  89 }