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	Simplify code, reduce code size, and drop remove function as no longer needed. Signed-off-by: Guenter Roeck <linux@roeck-us.net>
		
			
				
	
	
		
			668 lines
		
	
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			668 lines
		
	
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * ntc_thermistor.c - NTC Thermistors
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 *
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 *  Copyright (C) 2010 Samsung Electronics
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 *  MyungJoo Ham <myungjoo.ham@samsung.com>
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 *
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published by
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 * the Free Software Foundation; either version 2 of the License, or
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 * (at your option) any later version.
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 *
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 * This program is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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 *
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 */
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <linux/pm_runtime.h>
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#include <linux/math64.h>
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#include <linux/platform_device.h>
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#include <linux/err.h>
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#include <linux/of.h>
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#include <linux/of_device.h>
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#include <linux/platform_data/ntc_thermistor.h>
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#include <linux/iio/iio.h>
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#include <linux/iio/machine.h>
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#include <linux/iio/driver.h>
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#include <linux/iio/consumer.h>
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#include <linux/hwmon.h>
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#include <linux/hwmon-sysfs.h>
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#include <linux/thermal.h>
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struct ntc_compensation {
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	int		temp_c;
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	unsigned int	ohm;
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};
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/* Order matters, ntc_match references the entries by index */
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static const struct platform_device_id ntc_thermistor_id[] = {
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	{ "ncp15wb473", TYPE_NCPXXWB473 },
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	{ "ncp18wb473", TYPE_NCPXXWB473 },
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	{ "ncp21wb473", TYPE_NCPXXWB473 },
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	{ "ncp03wb473", TYPE_NCPXXWB473 },
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	{ "ncp15wl333", TYPE_NCPXXWL333 },
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	{ "b57330v2103", TYPE_B57330V2103},
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	{ "ncp03wf104", TYPE_NCPXXWF104 },
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	{ "ncp15xh103", TYPE_NCPXXXH103 },
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	{ },
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};
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/*
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 * A compensation table should be sorted by the values of .ohm
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 * in descending order.
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 * The following compensation tables are from the specification of Murata NTC
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 * Thermistors Datasheet
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 */
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static const struct ntc_compensation ncpXXwb473[] = {
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	{ .temp_c	= -40, .ohm	= 1747920 },
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	{ .temp_c	= -35, .ohm	= 1245428 },
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	{ .temp_c	= -30, .ohm	= 898485 },
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	{ .temp_c	= -25, .ohm	= 655802 },
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	{ .temp_c	= -20, .ohm	= 483954 },
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	{ .temp_c	= -15, .ohm	= 360850 },
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	{ .temp_c	= -10, .ohm	= 271697 },
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	{ .temp_c	= -5, .ohm	= 206463 },
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	{ .temp_c	= 0, .ohm	= 158214 },
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	{ .temp_c	= 5, .ohm	= 122259 },
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	{ .temp_c	= 10, .ohm	= 95227 },
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	{ .temp_c	= 15, .ohm	= 74730 },
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	{ .temp_c	= 20, .ohm	= 59065 },
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	{ .temp_c	= 25, .ohm	= 47000 },
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	{ .temp_c	= 30, .ohm	= 37643 },
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	{ .temp_c	= 35, .ohm	= 30334 },
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	{ .temp_c	= 40, .ohm	= 24591 },
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	{ .temp_c	= 45, .ohm	= 20048 },
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	{ .temp_c	= 50, .ohm	= 16433 },
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	{ .temp_c	= 55, .ohm	= 13539 },
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	{ .temp_c	= 60, .ohm	= 11209 },
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	{ .temp_c	= 65, .ohm	= 9328 },
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	{ .temp_c	= 70, .ohm	= 7798 },
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	{ .temp_c	= 75, .ohm	= 6544 },
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	{ .temp_c	= 80, .ohm	= 5518 },
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	{ .temp_c	= 85, .ohm	= 4674 },
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	{ .temp_c	= 90, .ohm	= 3972 },
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	{ .temp_c	= 95, .ohm	= 3388 },
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	{ .temp_c	= 100, .ohm	= 2902 },
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	{ .temp_c	= 105, .ohm	= 2494 },
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	{ .temp_c	= 110, .ohm	= 2150 },
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	{ .temp_c	= 115, .ohm	= 1860 },
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	{ .temp_c	= 120, .ohm	= 1615 },
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	{ .temp_c	= 125, .ohm	= 1406 },
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};
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static const struct ntc_compensation ncpXXwl333[] = {
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	{ .temp_c	= -40, .ohm	= 1610154 },
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	{ .temp_c	= -35, .ohm	= 1130850 },
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	{ .temp_c	= -30, .ohm	= 802609 },
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	{ .temp_c	= -25, .ohm	= 575385 },
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	{ .temp_c	= -20, .ohm	= 416464 },
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	{ .temp_c	= -15, .ohm	= 304219 },
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	{ .temp_c	= -10, .ohm	= 224193 },
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	{ .temp_c	= -5, .ohm	= 166623 },
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	{ .temp_c	= 0, .ohm	= 124850 },
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	{ .temp_c	= 5, .ohm	= 94287 },
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	{ .temp_c	= 10, .ohm	= 71747 },
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	{ .temp_c	= 15, .ohm	= 54996 },
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	{ .temp_c	= 20, .ohm	= 42455 },
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	{ .temp_c	= 25, .ohm	= 33000 },
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	{ .temp_c	= 30, .ohm	= 25822 },
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	{ .temp_c	= 35, .ohm	= 20335 },
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	{ .temp_c	= 40, .ohm	= 16115 },
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	{ .temp_c	= 45, .ohm	= 12849 },
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	{ .temp_c	= 50, .ohm	= 10306 },
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	{ .temp_c	= 55, .ohm	= 8314 },
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	{ .temp_c	= 60, .ohm	= 6746 },
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	{ .temp_c	= 65, .ohm	= 5503 },
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	{ .temp_c	= 70, .ohm	= 4513 },
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	{ .temp_c	= 75, .ohm	= 3721 },
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	{ .temp_c	= 80, .ohm	= 3084 },
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	{ .temp_c	= 85, .ohm	= 2569 },
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	{ .temp_c	= 90, .ohm	= 2151 },
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	{ .temp_c	= 95, .ohm	= 1809 },
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	{ .temp_c	= 100, .ohm	= 1529 },
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	{ .temp_c	= 105, .ohm	= 1299 },
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	{ .temp_c	= 110, .ohm	= 1108 },
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	{ .temp_c	= 115, .ohm	= 949 },
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	{ .temp_c	= 120, .ohm	= 817 },
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	{ .temp_c	= 125, .ohm	= 707 },
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};
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static const struct ntc_compensation ncpXXwf104[] = {
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	{ .temp_c	= -40, .ohm	= 4397119 },
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	{ .temp_c	= -35, .ohm	= 3088599 },
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	{ .temp_c	= -30, .ohm	= 2197225 },
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	{ .temp_c	= -25, .ohm	= 1581881 },
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	{ .temp_c	= -20, .ohm	= 1151037 },
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	{ .temp_c	= -15, .ohm	= 846579 },
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	{ .temp_c	= -10, .ohm	= 628988 },
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	{ .temp_c	= -5, .ohm	= 471632 },
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	{ .temp_c	= 0, .ohm	= 357012 },
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	{ .temp_c	= 5, .ohm	= 272500 },
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	{ .temp_c	= 10, .ohm	= 209710 },
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	{ .temp_c	= 15, .ohm	= 162651 },
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	{ .temp_c	= 20, .ohm	= 127080 },
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	{ .temp_c	= 25, .ohm	= 100000 },
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	{ .temp_c	= 30, .ohm	= 79222 },
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	{ .temp_c	= 35, .ohm	= 63167 },
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	{ .temp_c	= 40, .ohm	= 50677 },
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	{ .temp_c	= 45, .ohm	= 40904 },
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	{ .temp_c	= 50, .ohm	= 33195 },
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	{ .temp_c	= 55, .ohm	= 27091 },
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	{ .temp_c	= 60, .ohm	= 22224 },
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	{ .temp_c	= 65, .ohm	= 18323 },
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	{ .temp_c	= 70, .ohm	= 15184 },
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	{ .temp_c	= 75, .ohm	= 12635 },
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	{ .temp_c	= 80, .ohm	= 10566 },
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	{ .temp_c	= 85, .ohm	= 8873 },
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	{ .temp_c	= 90, .ohm	= 7481 },
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	{ .temp_c	= 95, .ohm	= 6337 },
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	{ .temp_c	= 100, .ohm	= 5384 },
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	{ .temp_c	= 105, .ohm	= 4594 },
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	{ .temp_c	= 110, .ohm	= 3934 },
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	{ .temp_c	= 115, .ohm	= 3380 },
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	{ .temp_c	= 120, .ohm	= 2916 },
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	{ .temp_c	= 125, .ohm	= 2522 },
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};
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static const struct ntc_compensation ncpXXxh103[] = {
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	{ .temp_c	= -40, .ohm	= 247565 },
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	{ .temp_c	= -35, .ohm	= 181742 },
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	{ .temp_c	= -30, .ohm	= 135128 },
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	{ .temp_c	= -25, .ohm	= 101678 },
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	{ .temp_c	= -20, .ohm	= 77373 },
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	{ .temp_c	= -15, .ohm	= 59504 },
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	{ .temp_c	= -10, .ohm	= 46222 },
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	{ .temp_c	= -5, .ohm	= 36244 },
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	{ .temp_c	= 0, .ohm	= 28674 },
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	{ .temp_c	= 5, .ohm	= 22878 },
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	{ .temp_c	= 10, .ohm	= 18399 },
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	{ .temp_c	= 15, .ohm	= 14910 },
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	{ .temp_c	= 20, .ohm	= 12169 },
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	{ .temp_c	= 25, .ohm	= 10000 },
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	{ .temp_c	= 30, .ohm	= 8271 },
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	{ .temp_c	= 35, .ohm	= 6883 },
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	{ .temp_c	= 40, .ohm	= 5762 },
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	{ .temp_c	= 45, .ohm	= 4851 },
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	{ .temp_c	= 50, .ohm	= 4105 },
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	{ .temp_c	= 55, .ohm	= 3492 },
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	{ .temp_c	= 60, .ohm	= 2985 },
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	{ .temp_c	= 65, .ohm	= 2563 },
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	{ .temp_c	= 70, .ohm	= 2211 },
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	{ .temp_c	= 75, .ohm	= 1915 },
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	{ .temp_c	= 80, .ohm	= 1666 },
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	{ .temp_c	= 85, .ohm	= 1454 },
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	{ .temp_c	= 90, .ohm	= 1275 },
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	{ .temp_c	= 95, .ohm	= 1121 },
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	{ .temp_c	= 100, .ohm	= 990 },
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	{ .temp_c	= 105, .ohm	= 876 },
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	{ .temp_c	= 110, .ohm	= 779 },
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	{ .temp_c	= 115, .ohm	= 694 },
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	{ .temp_c	= 120, .ohm	= 620 },
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	{ .temp_c	= 125, .ohm	= 556 },
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};
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/*
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 * The following compensation table is from the specification of EPCOS NTC
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 * Thermistors Datasheet
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 */
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static const struct ntc_compensation b57330v2103[] = {
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	{ .temp_c	= -40, .ohm	= 190030 },
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	{ .temp_c	= -35, .ohm	= 145360 },
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	{ .temp_c	= -30, .ohm	= 112060 },
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	{ .temp_c	= -25, .ohm	= 87041 },
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	{ .temp_c	= -20, .ohm	= 68104 },
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	{ .temp_c	= -15, .ohm	= 53665 },
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	{ .temp_c	= -10, .ohm	= 42576 },
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	{ .temp_c	= -5, .ohm	= 34001 },
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	{ .temp_c	= 0, .ohm	= 27326 },
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	{ .temp_c	= 5, .ohm	= 22096 },
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	{ .temp_c	= 10, .ohm	= 17973 },
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	{ .temp_c	= 15, .ohm	= 14703 },
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	{ .temp_c	= 20, .ohm	= 12090 },
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	{ .temp_c	= 25, .ohm	= 10000 },
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	{ .temp_c	= 30, .ohm	= 8311 },
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	{ .temp_c	= 35, .ohm	= 6941 },
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	{ .temp_c	= 40, .ohm	= 5825 },
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	{ .temp_c	= 45, .ohm	= 4911 },
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	{ .temp_c	= 50, .ohm	= 4158 },
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	{ .temp_c	= 55, .ohm	= 3536 },
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	{ .temp_c	= 60, .ohm	= 3019 },
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	{ .temp_c	= 65, .ohm	= 2588 },
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	{ .temp_c	= 70, .ohm	= 2227 },
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	{ .temp_c	= 75, .ohm	= 1924 },
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	{ .temp_c	= 80, .ohm	= 1668 },
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	{ .temp_c	= 85, .ohm	= 1451 },
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	{ .temp_c	= 90, .ohm	= 1266 },
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	{ .temp_c	= 95, .ohm	= 1108 },
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	{ .temp_c	= 100, .ohm	= 973 },
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	{ .temp_c	= 105, .ohm	= 857 },
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	{ .temp_c	= 110, .ohm	= 757 },
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	{ .temp_c	= 115, .ohm	= 671 },
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	{ .temp_c	= 120, .ohm	= 596 },
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	{ .temp_c	= 125, .ohm	= 531 },
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};
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struct ntc_data {
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	struct ntc_thermistor_platform_data *pdata;
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	const struct ntc_compensation *comp;
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	int n_comp;
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};
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#if defined(CONFIG_OF) && IS_ENABLED(CONFIG_IIO)
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static int ntc_adc_iio_read(struct ntc_thermistor_platform_data *pdata)
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{
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	struct iio_channel *channel = pdata->chan;
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	int raw, uv, ret;
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	ret = iio_read_channel_raw(channel, &raw);
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	if (ret < 0) {
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		pr_err("read channel() error: %d\n", ret);
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		return ret;
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	}
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	ret = iio_convert_raw_to_processed(channel, raw, &uv, 1000);
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	if (ret < 0) {
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		/* Assume 12 bit ADC with vref at pullup_uv */
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		uv = (pdata->pullup_uv * (s64)raw) >> 12;
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	}
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	return uv;
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}
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static const struct of_device_id ntc_match[] = {
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	{ .compatible = "murata,ncp15wb473",
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		.data = &ntc_thermistor_id[0] },
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	{ .compatible = "murata,ncp18wb473",
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		.data = &ntc_thermistor_id[1] },
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	{ .compatible = "murata,ncp21wb473",
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		.data = &ntc_thermistor_id[2] },
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	{ .compatible = "murata,ncp03wb473",
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		.data = &ntc_thermistor_id[3] },
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	{ .compatible = "murata,ncp15wl333",
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		.data = &ntc_thermistor_id[4] },
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	{ .compatible = "epcos,b57330v2103",
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		.data = &ntc_thermistor_id[5]},
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	{ .compatible = "murata,ncp03wf104",
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		.data = &ntc_thermistor_id[6] },
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	{ .compatible = "murata,ncp15xh103",
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		.data = &ntc_thermistor_id[7] },
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	/* Usage of vendor name "ntc" is deprecated */
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	{ .compatible = "ntc,ncp15wb473",
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		.data = &ntc_thermistor_id[0] },
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	{ .compatible = "ntc,ncp18wb473",
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		.data = &ntc_thermistor_id[1] },
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	{ .compatible = "ntc,ncp21wb473",
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		.data = &ntc_thermistor_id[2] },
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	{ .compatible = "ntc,ncp03wb473",
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		.data = &ntc_thermistor_id[3] },
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	{ .compatible = "ntc,ncp15wl333",
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		.data = &ntc_thermistor_id[4] },
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	{ },
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};
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MODULE_DEVICE_TABLE(of, ntc_match);
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static struct ntc_thermistor_platform_data *
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ntc_thermistor_parse_dt(struct device *dev)
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{
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	struct iio_channel *chan;
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	enum iio_chan_type type;
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	struct device_node *np = dev->of_node;
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	struct ntc_thermistor_platform_data *pdata;
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	int ret;
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	if (!np)
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		return NULL;
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	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
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	if (!pdata)
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		return ERR_PTR(-ENOMEM);
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	chan = devm_iio_channel_get(dev, NULL);
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	if (IS_ERR(chan))
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		return ERR_CAST(chan);
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 | 
						|
	ret = iio_get_channel_type(chan, &type);
 | 
						|
	if (ret < 0)
 | 
						|
		return ERR_PTR(ret);
 | 
						|
 | 
						|
	if (type != IIO_VOLTAGE)
 | 
						|
		return ERR_PTR(-EINVAL);
 | 
						|
 | 
						|
	if (of_property_read_u32(np, "pullup-uv", &pdata->pullup_uv))
 | 
						|
		return ERR_PTR(-ENODEV);
 | 
						|
	if (of_property_read_u32(np, "pullup-ohm", &pdata->pullup_ohm))
 | 
						|
		return ERR_PTR(-ENODEV);
 | 
						|
	if (of_property_read_u32(np, "pulldown-ohm", &pdata->pulldown_ohm))
 | 
						|
		return ERR_PTR(-ENODEV);
 | 
						|
 | 
						|
	if (of_find_property(np, "connected-positive", NULL))
 | 
						|
		pdata->connect = NTC_CONNECTED_POSITIVE;
 | 
						|
	else /* status change should be possible if not always on. */
 | 
						|
		pdata->connect = NTC_CONNECTED_GROUND;
 | 
						|
 | 
						|
	pdata->chan = chan;
 | 
						|
	pdata->read_uv = ntc_adc_iio_read;
 | 
						|
 | 
						|
	return pdata;
 | 
						|
}
 | 
						|
#else
 | 
						|
static struct ntc_thermistor_platform_data *
 | 
						|
ntc_thermistor_parse_dt(struct device *dev)
 | 
						|
{
 | 
						|
	return NULL;
 | 
						|
}
 | 
						|
 | 
						|
#define ntc_match	NULL
 | 
						|
 | 
						|
#endif
 | 
						|
 | 
						|
static inline u64 div64_u64_safe(u64 dividend, u64 divisor)
 | 
						|
{
 | 
						|
	if (divisor == 0 && dividend == 0)
 | 
						|
		return 0;
 | 
						|
	if (divisor == 0)
 | 
						|
		return UINT_MAX;
 | 
						|
	return div64_u64(dividend, divisor);
 | 
						|
}
 | 
						|
 | 
						|
static int get_ohm_of_thermistor(struct ntc_data *data, unsigned int uv)
 | 
						|
{
 | 
						|
	struct ntc_thermistor_platform_data *pdata = data->pdata;
 | 
						|
	u32 puv = pdata->pullup_uv;
 | 
						|
	u64 n, puo, pdo;
 | 
						|
	puo = pdata->pullup_ohm;
 | 
						|
	pdo = pdata->pulldown_ohm;
 | 
						|
 | 
						|
	if (uv == 0)
 | 
						|
		return (pdata->connect == NTC_CONNECTED_POSITIVE) ?
 | 
						|
			INT_MAX : 0;
 | 
						|
	if (uv >= puv)
 | 
						|
		return (pdata->connect == NTC_CONNECTED_POSITIVE) ?
 | 
						|
			0 : INT_MAX;
 | 
						|
 | 
						|
	if (pdata->connect == NTC_CONNECTED_POSITIVE && puo == 0)
 | 
						|
		n = div_u64(pdo * (puv - uv), uv);
 | 
						|
	else if (pdata->connect == NTC_CONNECTED_GROUND && pdo == 0)
 | 
						|
		n = div_u64(puo * uv, puv - uv);
 | 
						|
	else if (pdata->connect == NTC_CONNECTED_POSITIVE)
 | 
						|
		n = div64_u64_safe(pdo * puo * (puv - uv),
 | 
						|
				puo * uv - pdo * (puv - uv));
 | 
						|
	else
 | 
						|
		n = div64_u64_safe(pdo * puo * uv, pdo * (puv - uv) - puo * uv);
 | 
						|
 | 
						|
	if (n > INT_MAX)
 | 
						|
		n = INT_MAX;
 | 
						|
	return n;
 | 
						|
}
 | 
						|
 | 
						|
static void lookup_comp(struct ntc_data *data, unsigned int ohm,
 | 
						|
			int *i_low, int *i_high)
 | 
						|
{
 | 
						|
	int start, end, mid;
 | 
						|
 | 
						|
	/*
 | 
						|
	 * Handle special cases: Resistance is higher than or equal to
 | 
						|
	 * resistance in first table entry, or resistance is lower or equal
 | 
						|
	 * to resistance in last table entry.
 | 
						|
	 * In these cases, return i_low == i_high, either pointing to the
 | 
						|
	 * beginning or to the end of the table depending on the condition.
 | 
						|
	 */
 | 
						|
	if (ohm >= data->comp[0].ohm) {
 | 
						|
		*i_low = 0;
 | 
						|
		*i_high = 0;
 | 
						|
		return;
 | 
						|
	}
 | 
						|
	if (ohm <= data->comp[data->n_comp - 1].ohm) {
 | 
						|
		*i_low = data->n_comp - 1;
 | 
						|
		*i_high = data->n_comp - 1;
 | 
						|
		return;
 | 
						|
	}
 | 
						|
 | 
						|
	/* Do a binary search on compensation table */
 | 
						|
	start = 0;
 | 
						|
	end = data->n_comp;
 | 
						|
	while (start < end) {
 | 
						|
		mid = start + (end - start) / 2;
 | 
						|
		/*
 | 
						|
		 * start <= mid < end
 | 
						|
		 * data->comp[start].ohm > ohm >= data->comp[end].ohm
 | 
						|
		 *
 | 
						|
		 * We could check for "ohm == data->comp[mid].ohm" here, but
 | 
						|
		 * that is a quite unlikely condition, and we would have to
 | 
						|
		 * check again after updating start. Check it at the end instead
 | 
						|
		 * for simplicity.
 | 
						|
		 */
 | 
						|
		if (ohm >= data->comp[mid].ohm) {
 | 
						|
			end = mid;
 | 
						|
		} else {
 | 
						|
			start = mid + 1;
 | 
						|
			/*
 | 
						|
			 * ohm >= data->comp[start].ohm might be true here,
 | 
						|
			 * since we set start to mid + 1. In that case, we are
 | 
						|
			 * done. We could keep going, but the condition is quite
 | 
						|
			 * likely to occur, so it is worth checking for it.
 | 
						|
			 */
 | 
						|
			if (ohm >= data->comp[start].ohm)
 | 
						|
				end = start;
 | 
						|
		}
 | 
						|
		/*
 | 
						|
		 * start <= end
 | 
						|
		 * data->comp[start].ohm >= ohm >= data->comp[end].ohm
 | 
						|
		 */
 | 
						|
	}
 | 
						|
	/*
 | 
						|
	 * start == end
 | 
						|
	 * ohm >= data->comp[end].ohm
 | 
						|
	 */
 | 
						|
	*i_low = end;
 | 
						|
	if (ohm == data->comp[end].ohm)
 | 
						|
		*i_high = end;
 | 
						|
	else
 | 
						|
		*i_high = end - 1;
 | 
						|
}
 | 
						|
 | 
						|
static int get_temp_mc(struct ntc_data *data, unsigned int ohm)
 | 
						|
{
 | 
						|
	int low, high;
 | 
						|
	int temp;
 | 
						|
 | 
						|
	lookup_comp(data, ohm, &low, &high);
 | 
						|
	if (low == high) {
 | 
						|
		/* Unable to use linear approximation */
 | 
						|
		temp = data->comp[low].temp_c * 1000;
 | 
						|
	} else {
 | 
						|
		temp = data->comp[low].temp_c * 1000 +
 | 
						|
			((data->comp[high].temp_c - data->comp[low].temp_c) *
 | 
						|
			 1000 * ((int)ohm - (int)data->comp[low].ohm)) /
 | 
						|
			((int)data->comp[high].ohm - (int)data->comp[low].ohm);
 | 
						|
	}
 | 
						|
	return temp;
 | 
						|
}
 | 
						|
 | 
						|
static int ntc_thermistor_get_ohm(struct ntc_data *data)
 | 
						|
{
 | 
						|
	int read_uv;
 | 
						|
 | 
						|
	if (data->pdata->read_ohm)
 | 
						|
		return data->pdata->read_ohm();
 | 
						|
 | 
						|
	if (data->pdata->read_uv) {
 | 
						|
		read_uv = data->pdata->read_uv(data->pdata);
 | 
						|
		if (read_uv < 0)
 | 
						|
			return read_uv;
 | 
						|
		return get_ohm_of_thermistor(data, read_uv);
 | 
						|
	}
 | 
						|
	return -EINVAL;
 | 
						|
}
 | 
						|
 | 
						|
static int ntc_read_temp(void *data, int *temp)
 | 
						|
{
 | 
						|
	int ohm;
 | 
						|
 | 
						|
	ohm = ntc_thermistor_get_ohm(data);
 | 
						|
	if (ohm < 0)
 | 
						|
		return ohm;
 | 
						|
 | 
						|
	*temp = get_temp_mc(data, ohm);
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
static ssize_t ntc_show_type(struct device *dev,
 | 
						|
		struct device_attribute *attr, char *buf)
 | 
						|
{
 | 
						|
	return sprintf(buf, "4\n");
 | 
						|
}
 | 
						|
 | 
						|
static ssize_t ntc_show_temp(struct device *dev,
 | 
						|
		struct device_attribute *attr, char *buf)
 | 
						|
{
 | 
						|
	struct ntc_data *data = dev_get_drvdata(dev);
 | 
						|
	int ohm;
 | 
						|
 | 
						|
	ohm = ntc_thermistor_get_ohm(data);
 | 
						|
	if (ohm < 0)
 | 
						|
		return ohm;
 | 
						|
 | 
						|
	return sprintf(buf, "%d\n", get_temp_mc(data, ohm));
 | 
						|
}
 | 
						|
 | 
						|
static SENSOR_DEVICE_ATTR(temp1_type, S_IRUGO, ntc_show_type, NULL, 0);
 | 
						|
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ntc_show_temp, NULL, 0);
 | 
						|
 | 
						|
static struct attribute *ntc_attrs[] = {
 | 
						|
	&sensor_dev_attr_temp1_type.dev_attr.attr,
 | 
						|
	&sensor_dev_attr_temp1_input.dev_attr.attr,
 | 
						|
	NULL,
 | 
						|
};
 | 
						|
ATTRIBUTE_GROUPS(ntc);
 | 
						|
 | 
						|
static const struct thermal_zone_of_device_ops ntc_of_thermal_ops = {
 | 
						|
	.get_temp = ntc_read_temp,
 | 
						|
};
 | 
						|
 | 
						|
static int ntc_thermistor_probe(struct platform_device *pdev)
 | 
						|
{
 | 
						|
	struct thermal_zone_device *tz;
 | 
						|
	struct device *dev = &pdev->dev;
 | 
						|
	const struct of_device_id *of_id =
 | 
						|
			of_match_device(of_match_ptr(ntc_match), dev);
 | 
						|
	const struct platform_device_id *pdev_id;
 | 
						|
	struct ntc_thermistor_platform_data *pdata;
 | 
						|
	struct device *hwmon_dev;
 | 
						|
	struct ntc_data *data;
 | 
						|
 | 
						|
	pdata = ntc_thermistor_parse_dt(dev);
 | 
						|
	if (IS_ERR(pdata))
 | 
						|
		return PTR_ERR(pdata);
 | 
						|
	else if (pdata == NULL)
 | 
						|
		pdata = dev_get_platdata(dev);
 | 
						|
 | 
						|
	if (!pdata) {
 | 
						|
		dev_err(dev, "No platform init data supplied.\n");
 | 
						|
		return -ENODEV;
 | 
						|
	}
 | 
						|
 | 
						|
	/* Either one of the two is required. */
 | 
						|
	if (!pdata->read_uv && !pdata->read_ohm) {
 | 
						|
		dev_err(dev,
 | 
						|
			"Both read_uv and read_ohm missing. Need either one of the two.\n");
 | 
						|
		return -EINVAL;
 | 
						|
	}
 | 
						|
 | 
						|
	if (pdata->read_uv && pdata->read_ohm) {
 | 
						|
		dev_warn(dev,
 | 
						|
			 "Only one of read_uv and read_ohm is needed; ignoring read_uv.\n");
 | 
						|
		pdata->read_uv = NULL;
 | 
						|
	}
 | 
						|
 | 
						|
	if (pdata->read_uv && (pdata->pullup_uv == 0 ||
 | 
						|
				(pdata->pullup_ohm == 0 && pdata->connect ==
 | 
						|
				 NTC_CONNECTED_GROUND) ||
 | 
						|
				(pdata->pulldown_ohm == 0 && pdata->connect ==
 | 
						|
				 NTC_CONNECTED_POSITIVE) ||
 | 
						|
				(pdata->connect != NTC_CONNECTED_POSITIVE &&
 | 
						|
				 pdata->connect != NTC_CONNECTED_GROUND))) {
 | 
						|
		dev_err(dev, "Required data to use read_uv not supplied.\n");
 | 
						|
		return -EINVAL;
 | 
						|
	}
 | 
						|
 | 
						|
	data = devm_kzalloc(dev, sizeof(struct ntc_data), GFP_KERNEL);
 | 
						|
	if (!data)
 | 
						|
		return -ENOMEM;
 | 
						|
 | 
						|
	pdev_id = of_id ? of_id->data : platform_get_device_id(pdev);
 | 
						|
 | 
						|
	data->pdata = pdata;
 | 
						|
 | 
						|
	switch (pdev_id->driver_data) {
 | 
						|
	case TYPE_NCPXXWB473:
 | 
						|
		data->comp = ncpXXwb473;
 | 
						|
		data->n_comp = ARRAY_SIZE(ncpXXwb473);
 | 
						|
		break;
 | 
						|
	case TYPE_NCPXXWL333:
 | 
						|
		data->comp = ncpXXwl333;
 | 
						|
		data->n_comp = ARRAY_SIZE(ncpXXwl333);
 | 
						|
		break;
 | 
						|
	case TYPE_B57330V2103:
 | 
						|
		data->comp = b57330v2103;
 | 
						|
		data->n_comp = ARRAY_SIZE(b57330v2103);
 | 
						|
		break;
 | 
						|
	case TYPE_NCPXXWF104:
 | 
						|
		data->comp = ncpXXwf104;
 | 
						|
		data->n_comp = ARRAY_SIZE(ncpXXwf104);
 | 
						|
		break;
 | 
						|
	case TYPE_NCPXXXH103:
 | 
						|
		data->comp = ncpXXxh103;
 | 
						|
		data->n_comp = ARRAY_SIZE(ncpXXxh103);
 | 
						|
		break;
 | 
						|
	default:
 | 
						|
		dev_err(dev, "Unknown device type: %lu(%s)\n",
 | 
						|
				pdev_id->driver_data, pdev_id->name);
 | 
						|
		return -EINVAL;
 | 
						|
	}
 | 
						|
 | 
						|
	hwmon_dev = devm_hwmon_device_register_with_groups(dev, pdev_id->name,
 | 
						|
							   data, ntc_groups);
 | 
						|
	if (IS_ERR(hwmon_dev)) {
 | 
						|
		dev_err(dev, "unable to register as hwmon device.\n");
 | 
						|
		return PTR_ERR(hwmon_dev);
 | 
						|
	}
 | 
						|
 | 
						|
	dev_info(dev, "Thermistor type: %s successfully probed.\n",
 | 
						|
		 pdev_id->name);
 | 
						|
 | 
						|
	tz = devm_thermal_zone_of_sensor_register(dev, 0, data,
 | 
						|
						  &ntc_of_thermal_ops);
 | 
						|
	if (IS_ERR(tz))
 | 
						|
		dev_dbg(dev, "Failed to register to thermal fw.\n");
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
static struct platform_driver ntc_thermistor_driver = {
 | 
						|
	.driver = {
 | 
						|
		.name = "ntc-thermistor",
 | 
						|
		.of_match_table = of_match_ptr(ntc_match),
 | 
						|
	},
 | 
						|
	.probe = ntc_thermistor_probe,
 | 
						|
	.id_table = ntc_thermistor_id,
 | 
						|
};
 | 
						|
 | 
						|
module_platform_driver(ntc_thermistor_driver);
 | 
						|
 | 
						|
MODULE_DESCRIPTION("NTC Thermistor Driver");
 | 
						|
MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
 | 
						|
MODULE_LICENSE("GPL");
 | 
						|
MODULE_ALIAS("platform:ntc-thermistor");
 |