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"
  27
  28 #include <linux/string.h>
  29 #include <linux/delay.h>
  30
  31 int comedi_data_write(void *dev, unsigned int subdev, unsigned int chan,
  32                       unsigned int range, unsigned int aref, unsigned int data)
  33 {
  34         struct comedi_insn insn;
  35
  36         memset(&insn, 0, sizeof(insn));
  37         insn.insn = INSN_WRITE;
  38         insn.n = 1;
  39         insn.data = &data;
  40         insn.subdev = subdev;
  41         insn.chanspec = CR_PACK(chan, range, aref);
  42
  43         return comedi_do_insn(dev, &insn);
  44 }
  45
  46 int comedi_data_read(void *dev, unsigned int subdev, unsigned int chan,
  47                      unsigned int range, unsigned int aref, unsigned int *data)
  48 {
  49         struct comedi_insn insn;
  50
  51         memset(&insn, 0, sizeof(insn));
  52         insn.insn = INSN_READ;
  53         insn.n = 1;
  54         insn.data = data;
  55         insn.subdev = subdev;
  56         insn.chanspec = CR_PACK(chan, range, aref);
  57
  58         return comedi_do_insn(dev, &insn);
  59 }
  60
  61 int comedi_data_read_hint(void *dev, unsigned int subdev,
  62                           unsigned int chan, unsigned int range,
  63                           unsigned int aref)
  64 {
  65         struct comedi_insn insn;
  66         unsigned int dummy_data;
  67
  68         memset(&insn, 0, sizeof(insn));
  69         insn.insn = INSN_READ;
  70         insn.n = 0;
  71         insn.data = &dummy_data;
  72         insn.subdev = subdev;
  73         insn.chanspec = CR_PACK(chan, range, aref);
  74
  75         return comedi_do_insn(dev, &insn);
  76 }
  77
  78 int comedi_data_read_delayed(void *dev, unsigned int subdev,
  79                              unsigned int chan, unsigned int range,
  80                              unsigned int aref, unsigned int *data,
  81                              unsigned int nano_sec)
  82 {
  83         int retval;
  84
  85         retval = comedi_data_read_hint(dev, subdev, chan, range, aref);
  86         if (retval < 0)
  87                 return retval;
  88
  89         udelay((nano_sec + 999) / 1000);
  90
  91         return comedi_data_read(dev, subdev, chan, range, aref, data);
  92 }