1/* SPDX-License-Identifier: GPL-2.0-or-later */
 2/*
 3    lm75.h - Part of lm_sensors, Linux kernel modules for hardware
 4	      monitoring
 5    Copyright (c) 2003 Mark M. Hoffman <mhoffman@lightlink.com>
 6
 7*/
 8
 9/*
10    This file contains common code for encoding/decoding LM75 type
11    temperature readings, which are emulated by many of the chips
12    we support.  As the user is unlikely to load more than one driver
13    which contains this code, we don't worry about the wasted space.
14*/
15
16#include <linux/kernel.h>
 
17
18/* straight from the datasheet */
19#define LM75_TEMP_MIN (-55000)
20#define LM75_TEMP_MAX 125000
21#define LM75_SHUTDOWN 0x01
22
23/* TEMP: 0.001C/bit (-55C to +125C)
24   REG: (0.5C/bit, two's complement) << 7 */
 
 
25static inline u16 LM75_TEMP_TO_REG(long temp)
26{
27	int ntemp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
 
28	ntemp += (ntemp < 0 ? -250 : 250);
29	return (u16)((ntemp / 500) << 7);
30}
31
32static inline int LM75_TEMP_FROM_REG(u16 reg)
33{
34	/* use integer division instead of equivalent right shift to
35	   guarantee arithmetic shift and preserve the sign */
 
 
36	return ((s16)reg / 128) * 500;
37}

 1/* SPDX-License-Identifier: GPL-2.0-or-later */
 2/*
 3 * lm75.h - Part of lm_sensors, Linux kernel modules for hardware monitoring
 4 * Copyright (c) 2003 Mark M. Hoffman <mhoffman@lightlink.com>
 5 */
 
 
 6
 7/*
 8 * This file contains common code for encoding/decoding LM75 type
 9 * temperature readings, which are emulated by many of the chips
10 * we support.  As the user is unlikely to load more than one driver
11 * which contains this code, we don't worry about the wasted space.
12 */
13
14#include <linux/minmax.h>
15#include <linux/types.h>
16
17/* straight from the datasheet */
18#define LM75_TEMP_MIN (-55000)
19#define LM75_TEMP_MAX 125000
20#define LM75_SHUTDOWN 0x01
21
22/*
23 * TEMP: 0.001C/bit (-55C to +125C)
24 * REG: (0.5C/bit, two's complement) << 7
25 */
26static inline u16 LM75_TEMP_TO_REG(long temp)
27{
28	int ntemp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
29
30	ntemp += (ntemp < 0 ? -250 : 250);
31	return (u16)((ntemp / 500) << 7);
32}
33
34static inline int LM75_TEMP_FROM_REG(u16 reg)
35{
36	/*
37	 * use integer division instead of equivalent right shift to
38	 * guarantee arithmetic shift and preserve the sign
39	 */
40	return ((s16)reg / 128) * 500;
41}