path: root/drivers/hwmon/lm63.c

/*
 * lm63.c - driver for the National Semiconductor LM63 temperature sensor
 *          with integrated fan control
 * Copyright (C) 2004-2008  Jean Delvare <jdelvare@suse.de>
 * Based on the lm90 driver.
 *
 * The LM63 is a sensor chip made by National Semiconductor. It measures
 * two temperatures (its own and one external one) and the speed of one
 * fan, those speed it can additionally control. Complete datasheet can be
 * obtained from National's website at:
 *   http://www.national.com/pf/LM/LM63.html
 *
 * The LM63 is basically an LM86 with fan speed monitoring and control
 * capabilities added. It misses some of the LM86 features though:
 *  - No low limit for local temperature.
 *  - No critical limit for local temperature.
 *  - Critical limit for remote temperature can be changed only once. We
 *    will consider that the critical limit is read-only.
 *
 * The datasheet isn't very clear about what the tachometer reading is.
 * I had a explanation from National Semiconductor though. The two lower
 * bits of the read value have to be masked out. The value is still 16 bit
 * in width.
 *
 * 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.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon-sysfs.h>
#include <linux/hwmon.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
#include <linux/types.h>

/*
 * Addresses to scan
 * Address is fully defined internally and cannot be changed except for
 * LM64 which has one pin dedicated to address selection.
 * LM63 and LM96163 have address 0x4c.
 * LM64 can have address 0x18 or 0x4e.
 */

static const unsigned short normal_i2c[] = { 0x18, 0x4c, 0x4e, I2C_CLIENT_END };

/*
 * The LM63 registers
 */

#define LM63_REG_CONFIG1		0x03
#define LM63_REG_CONVRATE		0x04
#define LM63_REG_CONFIG2		0xBF
#define LM63_REG_CONFIG_FAN		0x4A

#define LM63_REG_TACH_COUNT_MSB		0x47
#define LM63_REG_TACH_COUNT_LSB		0x46
#define LM63_REG_TACH_LIMIT_MSB		0x49
#define LM63_REG_TACH_LIMIT_LSB		0x48

#define LM63_REG_PWM_VALUE		0x4C
#define LM63_REG_PWM_FREQ		0x4D
#define LM63_REG_LUT_TEMP_HYST		0x4F
#define LM63_REG_LUT_TEMP(nr)		(0x50 + 2 * (nr))
#define LM63_REG_LUT_PWM(nr)		(0x51 + 2 * (nr))

#define LM63_REG_LOCAL_TEMP		0x00
#define LM63_REG_LOCAL_HIGH		0x05

#define LM63_REG_REMOTE_TEMP_MSB	0x01
#define LM63_REG_REMOTE_TEMP_LSB	0x10
#define LM63_REG_REMOTE_OFFSET_MSB	0x11
#define LM63_REG_REMOTE_OFFSET_LSB	0x12
#define LM63_REG_REMOTE_HIGH_MSB	0x07
#define LM63_REG_REMOTE_HIGH_LSB	0x13
#define LM63_REG_REMOTE_LOW_MSB		0x08
#define LM63_REG_REMOTE_LOW_LSB		0x14
#define LM63_REG_REMOTE_TCRIT		0x19
#define LM63_REG_REMOTE_TCRIT_HYST	0x21

#define LM63_REG_ALERT_STATUS		0x02
#define LM63_REG_ALERT_MASK		0x16

#define LM63_REG_MAN_ID			0xFE
#define LM63_REG_CHIP_ID		0xFF

#define LM96163_REG_TRUTHERM		0x30
#define LM96163_REG_REMOTE_TEMP_U_MSB	0x31
#define LM96163_REG_REMOTE_TEMP_U_LSB	0x32
#define LM96163_REG_CONFIG_ENHANCED	0x45

#define LM63_MAX_CONVRATE		9

#define LM63_MAX_CONVRATE_HZ		32
#define LM96163_MAX_CONVRATE_HZ		26

/*
 * Conversions and various macros
 * For tachometer counts, the LM63 uses 16-bit values.
 * For local temperature and high limit, remote critical limit and hysteresis
 * value, it uses signed 8-bit values with LSB = 1 degree Celsius.
 * For remote temperature, low and high limits, it uses signed 11-bit values
 * with LSB = 0.125 degree Celsius, left-justified in 16-bit registers.
 * For LM64 the actual remote diode temperature is 16 degree Celsius higher
 * than the register reading. Remote temperature setpoints have to be
 * adapted accordingly.
 */

#define FAN_FROM_REG(reg)	((reg) == 0xFFFC || (reg) == 0 ? 0 : \
				 5400000 / (reg))
#define FAN_TO_REG(val)		((val) <= 82 ? 0xFFFC : \
				 (5400000 / (val)) & 0xFFFC)
#define TEMP8_FROM_REG(reg)	((reg) * 1000)
#define TEMP8_TO_REG(val)	((val) <= -128000 ? -128 : \
				 (val) >= 127000 ? 127 : \
				 (val) < 0 ? ((val) - 500) / 1000 : \
				 ((val) + 500) / 1000)
#define TEMP8U_TO_REG(val)	((val) <= 0 ? 0 : \
				 (val) >= 255000 ? 255 : \
				 ((val) + 500) / 1000)
#define TEMP11_FROM_REG(reg)	((reg) / 32 * 125)
#define TEMP11_TO_REG(val)	((val) <= -128000 ? 0x8000 : \
				 (val) >= 127875 ? 0x7FE0 : \
				 (val) < 0 ? ((val) - 62) / 125 * 32 : \
				 ((val) + 62) / 125 * 32)
#define TEMP11U_TO_REG(val)	((val) <= 0 ? 0 : \
				 (val) >= 255875 ? 0xFFE0 : \
				 ((val) + 62) / 125 * 32)
#define HYST_TO_REG(val)	((val) <= 0 ? 0 : \
				 (val) >= 127000 ? 127 : \
				 ((val) + 500) / 1000)

#define UPDATE_INTERVAL(max, rate) \
			((1000 << (LM63_MAX_CONVRATE - (rate))) / (max))

enum chips { lm63, lm64, lm96163 };

/*
 * Client data (each client gets its own)
 */

struct lm63_data {
	struct device *hwmon_dev;
	struct mutex update_lock;
	char valid; /* zero until following fields are valid */
	char lut_valid; /* zero until lut fields are valid */
	unsigned long last_updated; /* in jiffies */
	unsigned long lut_last_updated; /* in jiffies */
	enum chips kind;
	int temp2_offset;

	int update_interval;	/* in milliseconds */
	int max_convrate_hz;
	int lut_size;		/* 8 or 12 */

	/* registers values */
	u8 config, config_fan;
	u16 fan[2];	/* 0: input
			   1: low limit */
	u8 pwm1_freq;
	u8 pwm1[13];	/* 0: current output
			   1-12: lookup table */
	s8 temp8[15];	/* 0: local input
			   1: local high limit
			   2: remote critical limit
			   3-14: lookup table */
	s16 temp11[4];	/* 0: remote input
			   1: remote low limit
			   2: remote high limit
			   3: remote offset */
	u16 temp11u;	/* remote input (unsigned) */
	u8 temp2_crit_hyst;
	u8 lut_temp_hyst;
	u8 alarms;
	bool pwm_highres;
	bool lut_temp_highres;
	bool remote_unsigned; /* true if unsigned remote upper limits */
	bool trutherm