linux-imx

// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * ntc_thermistor.c - NTC Thermistors

 *

 *  Copyright (C) 2010 Samsung Electronics

 *  MyungJoo Ham <myungjoo.ham@samsung.com>

 */

​

#include <linux/slab.h>

#include <linux/module.h>

#include <linux/pm_runtime.h>

#include <linux/math64.h>

#include <linux/platform_device.h>

#include <linux/err.h>

#include <linux/of.h>

#include <linux/of_device.h>

​

#include <linux/platform_data/ntc_thermistor.h>

​

#include <linux/iio/iio.h>

#include <linux/iio/machine.h>

#include <linux/iio/driver.h>

#include <linux/iio/consumer.h>

​

#include <linux/hwmon.h>

​

struct ntc_compensation {

    int     temp_c;

    unsigned int    ohm;

};

​

/*

 * Used as index in a zero-terminated array, holes not allowed so

 * that NTC_LAST is the first empty array entry.

 */

enum {

    NTC_B57330V2103,

    NTC_B57891S0103,

    NTC_NCP03WB473,

    NTC_NCP03WF104,

    NTC_NCP15WB473,

    NTC_NCP15WL333,

    NTC_NCP15XH103,

    NTC_NCP18WB473,

    NTC_NCP21WB473,

    NTC_LAST,

};

​

static const struct platform_device_id ntc_thermistor_id[] = {

    [NTC_B57330V2103]     = { "b57330v2103",     TYPE_B57330V2103 },

    [NTC_B57891S0103]     = { "b57891s0103",     TYPE_B57891S0103 },

    [NTC_NCP03WB473]      = { "ncp03wb473",      TYPE_NCPXXWB473 },

    [NTC_NCP03WF104]      = { "ncp03wf104",      TYPE_NCPXXWF104 },

    [NTC_NCP15WB473]      = { "ncp15wb473",      TYPE_NCPXXWB473 },

    [NTC_NCP15WL333]      = { "ncp15wl333",      TYPE_NCPXXWL333 },

    [NTC_NCP15XH103]      = { "ncp15xh103",      TYPE_NCPXXXH103 },

    [NTC_NCP18WB473]      = { "ncp18wb473",      TYPE_NCPXXWB473 },

    [NTC_NCP21WB473]      = { "ncp21wb473",      TYPE_NCPXXWB473 },

    [NTC_LAST]            = { },

};

​

/*

 * A compensation table should be sorted by the values of .ohm

 * in descending order.

 * The following compensation tables are from the specification of Murata NTC

 * Thermistors Datasheet

 */

static const struct ntc_compensation ncpXXwb473[] = {

    { .temp_c   = -40, .ohm = 1747920 },

    { .temp_c   = -35, .ohm = 1245428 },

    { .temp_c   = -30, .ohm = 898485 },

    { .temp_c   = -25, .ohm = 655802 },

    { .temp_c   = -20, .ohm = 483954 },

    { .temp_c   = -15, .ohm = 360850 },

    { .temp_c   = -10, .ohm = 271697 },

    { .temp_c   = -5, .ohm  = 206463 },

    { .temp_c   = 0, .ohm   = 158214 },

    { .temp_c   = 5, .ohm   = 122259 },

    { .temp_c   = 10, .ohm  = 95227 },

    { .temp_c   = 15, .ohm  = 74730 },

    { .temp_c   = 20, .ohm  = 59065 },

    { .temp_c   = 25, .ohm  = 47000 },

    { .temp_c   = 30, .ohm  = 37643 },

    { .temp_c   = 35, .ohm  = 30334 },

    { .temp_c   = 40, .ohm  = 24591 },

    { .temp_c   = 45, .ohm  = 20048 },

    { .temp_c   = 50, .ohm  = 16433 },

    { .temp_c   = 55, .ohm  = 13539 },

    { .temp_c   = 60, .ohm  = 11209 },

    { .temp_c   = 65, .ohm  = 9328 },

    { .temp_c   = 70, .ohm  = 7798 },

    { .temp_c   = 75, .ohm  = 6544 },