path: root/drivers/hwmon/lm75.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * lm75.c - Part of lm_sensors, Linux kernel modules for hardware
 *	 monitoring
 * Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl>
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/regmap.h>
#include <linux/util_macros.h>
#include <linux/regulator/consumer.h>
#include "lm75.h"

/*
 * This driver handles the LM75 and compatible digital temperature sensors.
 */

enum lm75_type {		/* keep sorted in alphabetical order */
	adt75,
	as6200,
	at30ts74,
	ds1775,
	ds75,
	ds7505,
	g751,
	lm75,
	lm75a,
	lm75b,
	max6625,
	max6626,
	max31725,
	mcp980x,
	pct2075,
	stds75,
	stlm75,
	tcn75,
	tmp100,
	tmp101,
	tmp105,
	tmp112,
	tmp175,
	tmp275,
	tmp75,
	tmp75b,
	tmp75c,
	tmp1075,
};

/**
 * struct lm75_params - lm75 configuration parameters.
 * @config_reg_16bits:	Configure register size is 2 bytes.
 * @set_mask:		Bits to set in configuration register when configuring
 *			the chip.
 * @clr_mask:		Bits to clear in configuration register when configuring
 *			the chip.
 * @default_resolution:	Default number of bits to represent the temperature
 *			value.
 * @resolution_limits:	Limit register resolution. Optional. Should be set if
 *			the resolution of limit registers does not match the
 *			resolution of the temperature register.
 * @resolutions:	List of resolutions associated with sample times.
 *			Optional. Should be set if num_sample_times is larger
 *			than 1, and if the resolution changes with sample times.
 *			If set, number of entries must match num_sample_times.
 * @default_sample_time:Sample time to be set by default.
 * @num_sample_times:	Number of possible sample times to be set. Optional.
 *			Should be set if the number of sample times is larger
 *			than one.
 * @sample_times:	All the possible sample times to be set. Mandatory if
 *			num_sample_times is larger than 1. If set, number of
 *			entries must match num_sample_times.
 * @alarm:		Alarm bit is supported.
 */

struct lm75_params {
	bool			config_reg_16bits;
	u16			set_mask;
	u16			clr_mask;
	u8			default_resolution;
	u8			resolution_limits;
	const u8		*resolutions;
	unsigned int		default_sample_time;
	u8			num_sample_times;
	const unsigned int	*sample_times;
	bool			alarm;
};

/* Addresses scanned */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
					0x4d, 0x4e, 0x4f, I2C_CLIENT_END };

/* The LM75 registers */
#define LM75_REG_TEMP		0x00
#define LM75_REG_CONF		0x01
#define LM75_REG_HYST		0x02
#define LM75_REG_MAX		0x03
#define PCT2075_REG_IDLE	0x04

/* Each client has this additional data */
struct lm75_data {
	struct i2c_client		*client;
	struct regmap			*regmap;
	struct regulator		*vs;
	u16				orig_conf;
	u16				current_conf;
	u8				resolution;	/* In bits, 9 to 16 */
	unsigned int			sample_time;	/* In ms */
	enum lm75_type			kind;
	const struct lm75_params	*params;
};

/*-----------------------------------------------------------------------*/

static const u8 lm75_sample_set_masks[] = { 0 << 5, 1 << 5, 2 << 5, 3 << 5 };

#define LM75_SAMPLE_CLEAR_MASK	(3 << 5)

/* The structure below stores the configuration values of the supported devices.
 * In case of being supported multiple configurations, the default one must
 * always be the first element of the array
 */
static const struct lm75_params device_params[] = {
	[adt75] = {
		.clr_mask = 1 << 5,	/* not one-shot mode */
		.default_resolution = 12,
		.default_sample_time = MSEC_PER_SEC / 10,
	},
	[as6200] = {
		.config_reg_16bits = true,
		.set_mask = 0x94C0,	/* 8 sample/s, 4 CF, positive polarity */
		.default_resolution = 12,
		.default_sample_time = 125,
		.num_sample_times = 4,
		.sample_times = (unsigned int []){ 125, 250, 1000, 4000 },
		.alarm = true,
	},
	[at30ts74] = {
		.set_mask = 3 << 5,	/* 12-bit mode*/
		.default_resolution = 12,
		.default_sample_time = 200,
		.num_sample_times = 4,
		.sample_times = (unsigned int []){ 25, 50, 100, 200 },
		.resolutions = (u8 []) {9, 10, 11, 12 },
	},
	[ds1775] = {
		.clr_mask = 3 << 5,
		.set_mask = 2 << 5,	/* 11-bit mode */
		.default_resolution = 11,
		.default_sample_time = 500,
		.num_sample_times = 4,
		.sample_times = (unsigned int []){ 125, 250, 500, 1000 },
		.resolutions = (u8 []) {9, 10, 11, 12 },
	},
	[ds75] = {
		.clr_mask = 3 << 5,
		.set_mask = 2 << 5,	/* 11-bit mode */
		.default_resolution = 11,
		.default_sample_time = 600,
		.num_sample_times = 4,
		.sample_times = (unsigned int []){ 150, 300, 600, 1200 },
		.resolutions = (u8 []) {9, 10, 11, 12 },
	},
	[stds75] = {
		.clr_mask = 3 << 5,
		.set_mask = 2 << 5,	/* 11-bit mode */
		.default_resolution = 11,
		.default_sample_time = 600,
		.num_sample_times = 4,
		.sample_times = (unsigned int []){ 150, 300, 600, 1200 },
		.resolutions = (u8 []) {9, 10, 11, 12 },
	},
	[stlm75] = {
		.default_resolution = 9,
		.default_sample_time = MSEC_PER_SEC / 6,
	},
	[ds7505] = {
		.set_mask = 3 << 5,	/* 12-bit mode*/
		.default_resolution = 12,
		.default_sample_time = 200,
		.num_sample_times = 4,
		.sample_times = (unsigned int []){ 25, 50, 100