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-rw-r--r--drivers/hwmon/lm75.h49
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diff --git a/drivers/hwmon/lm75.h b/drivers/hwmon/lm75.h
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+/*
+ lm75.h - Part of lm_sensors, Linux kernel modules for hardware
+ monitoring
+ Copyright (c) 2003 Mark M. Hoffman <mhoffman@lightlink.com>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+/*
+ This file contains common code for encoding/decoding LM75 type
+ temperature readings, which are emulated by many of the chips
+ we support. As the user is unlikely to load more than one driver
+ which contains this code, we don't worry about the wasted space.
+*/
+
+#include <linux/i2c-sensor.h>
+
+/* straight from the datasheet */
+#define LM75_TEMP_MIN (-55000)
+#define LM75_TEMP_MAX 125000
+
+/* TEMP: 0.001C/bit (-55C to +125C)
+ REG: (0.5C/bit, two's complement) << 7 */
+static inline u16 LM75_TEMP_TO_REG(int temp)
+{
+ int ntemp = SENSORS_LIMIT(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
+ ntemp += (ntemp<0 ? -250 : 250);
+ return (u16)((ntemp / 500) << 7);
+}
+
+static inline int LM75_TEMP_FROM_REG(u16 reg)
+{
+ /* use integer division instead of equivalent right shift to
+ guarantee arithmetic shift and preserve the sign */
+ return ((s16)reg / 128) * 500;
+}
+