include/linux/platform_data/ntc_thermistor.h

   1 /*
   2  * ntc_thermistor.h - NTC Thermistors
   3  *
   4  *  Copyright (C) 2010 Samsung Electronics
   5  *  MyungJoo Ham <myungjoo.ham@samsung.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21 #ifndef _LINUX_NTC_H
  22 #define _LINUX_NTC_H
  23
  24 struct iio_channel;
  25
  26 enum ntc_thermistor_type {
  27         TYPE_NCPXXWB473,
  28         TYPE_NCPXXWL333,
  29 };
  30
  31 struct ntc_thermistor_platform_data {
  32         /*
  33          * One (not both) of read_uV and read_ohm should be provided and only
  34          * one of the two should be provided.
  35          * Both functions should return negative value for an error case.
  36          *
  37          * pullup_uV, pullup_ohm, pulldown_ohm, and connect are required to use
  38          * read_uV()
  39          *
  40          * How to setup pullup_ohm, pulldown_ohm, and connect is
  41          * described at Documentation/hwmon/ntc_thermistor
  42          *
  43          * pullup/down_ohm: 0 for infinite / not-connected
  44          *
  45          * chan: iio_channel pointer to communicate with the ADC which the
  46          * thermistor is using for conversion of the analog values.
  47          */
  48         int (*read_uv)(struct ntc_thermistor_platform_data *);
  49         unsigned int pullup_uv;
  50
  51         unsigned int pullup_ohm;
  52         unsigned int pulldown_ohm;
  53         enum { NTC_CONNECTED_POSITIVE, NTC_CONNECTED_GROUND } connect;
  54         struct iio_channel *chan;
  55
  56         int (*read_ohm)(void);
  57 };
  58
  59 #endif /* _LINUX_NTC_H */