74ba9207e1
Based on 1 normalized pattern(s): 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 441 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520071858.739733335@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
38 lines
1.1 KiB
C
38 lines
1.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0-or-later */
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/*
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lm75.h - Part of lm_sensors, Linux kernel modules for hardware
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monitoring
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Copyright (c) 2003 Mark M. Hoffman <mhoffman@lightlink.com>
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*/
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/*
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This file contains common code for encoding/decoding LM75 type
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temperature readings, which are emulated by many of the chips
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we support. As the user is unlikely to load more than one driver
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which contains this code, we don't worry about the wasted space.
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*/
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#include <linux/kernel.h>
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/* straight from the datasheet */
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#define LM75_TEMP_MIN (-55000)
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#define LM75_TEMP_MAX 125000
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#define LM75_SHUTDOWN 0x01
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/* TEMP: 0.001C/bit (-55C to +125C)
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REG: (0.5C/bit, two's complement) << 7 */
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static inline u16 LM75_TEMP_TO_REG(long temp)
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{
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int ntemp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
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ntemp += (ntemp < 0 ? -250 : 250);
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return (u16)((ntemp / 500) << 7);
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}
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static inline int LM75_TEMP_FROM_REG(u16 reg)
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{
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/* use integer division instead of equivalent right shift to
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guarantee arithmetic shift and preserve the sign */
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return ((s16)reg / 128) * 500;
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}
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