path: root/drivers/hwmon/adt7470.c

/*
 * A hwmon driver for the Analog Devices ADT7470
 * Copyright (C) 2007 IBM
 *
 * Author: Darrick J. Wong <djwong@us.ibm.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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/log2.h>
#include <linux/kthread.h>
#include <linux/slab.h>

/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2C, 0x2E, 0x2F, I2C_CLIENT_END };

/* ADT7470 registers */
#define ADT7470_REG_BASE_ADDR			0x20
#define ADT7470_REG_TEMP_BASE_ADDR		0x20
#define ADT7470_REG_TEMP_MAX_ADDR		0x29
#define ADT7470_REG_FAN_BASE_ADDR		0x2A
#define ADT7470_REG_FAN_MAX_ADDR		0x31
#define ADT7470_REG_PWM_BASE_ADDR		0x32
#define ADT7470_REG_PWM_MAX_ADDR		0x35
#define ADT7470_REG_PWM_MAX_BASE_ADDR		0x38
#define ADT7470_REG_PWM_MAX_MAX_ADDR		0x3B
#define ADT7470_REG_CFG				0x40
#define		ADT7470_FSPD_MASK		0x04
#define ADT7470_REG_ALARM1			0x41
#define		ADT7470_R1T_ALARM		0x01
#define		ADT7470_R2T_ALARM		0x02
#define		ADT7470_R3T_ALARM		0x04
#define		ADT7470_R4T_ALARM		0x08
#define		ADT7470_R5T_ALARM		0x10
#define		ADT7470_R6T_ALARM		0x20
#define		ADT7470_R7T_ALARM		0x40
#define		ADT7470_OOL_ALARM		0x80
#define ADT7470_REG_ALARM2			0x42
#define		ADT7470_R8T_ALARM		0x01
#define		ADT7470_R9T_ALARM		0x02
#define		ADT7470_R10T_ALARM		0x04
#define		ADT7470_FAN1_ALARM		0x10
#define		ADT7470_FAN2_ALARM		0x20
#define		ADT7470_FAN3_ALARM		0x40
#define		ADT7470_FAN4_ALARM		0x80
#define ADT7470_REG_TEMP_LIMITS_BASE_ADDR	0x44
#define ADT7470_REG_TEMP_LIMITS_MAX_ADDR	0x57
#define ADT7470_REG_FAN_MIN_BASE_ADDR		0x58
#define ADT7470_REG_FAN_MIN_MAX_ADDR		0x5F
#define ADT7470_REG_FAN_MAX_BASE_ADDR		0x60
#define ADT7470_REG_FAN_MAX_MAX_ADDR		0x67
#define ADT7470_REG_PWM_CFG_BASE_ADDR		0x68
#define ADT7470_REG_PWM12_CFG			0x68
#define		ADT7470_PWM2_AUTO_MASK		0x40
#define		ADT7470_PWM1_AUTO_MASK		0x80
#define		ADT7470_PWM_AUTO_MASK		0xC0
#define ADT7470_REG_PWM34_CFG			0x69
#define		ADT7470_PWM3_AUTO_MASK		0x40
#define		ADT7470_PWM4_AUTO_MASK		0x80
#define	ADT7470_REG_PWM_MIN_BASE_ADDR		0x6A
#define ADT7470_REG_PWM_MIN_MAX_ADDR		0x6D
#define ADT7470_REG_PWM_TEMP_MIN_BASE_ADDR	0x6E
#define ADT7470_REG_PWM_TEMP_MIN_MAX_ADDR	0x71
#define ADT7470_REG_ACOUSTICS12			0x75
#define ADT7470_REG_ACOUSTICS34			0x76
#define ADT7470_REG_DEVICE			0x3D
#define ADT7470_REG_VENDOR			0x3E
#define ADT7470_REG_REVISION			0x3F
#define ADT7470_REG_ALARM1_MASK			0x72
#define ADT7470_REG_ALARM2_MASK			0x73
#define ADT7470_REG_PWM_AUTO_TEMP_BASE_ADDR	0x7C
#define ADT7470_REG_PWM_AUTO_TEMP_MAX_ADDR	0x7D
#define ADT7470_REG_MAX_ADDR			0x81

#define ADT7470_TEMP_COUNT	10
#define ADT7470_TEMP_REG(x)	(ADT7470_REG_TEMP_BASE_ADDR + (x))
#define ADT7470_TEMP_MIN_REG(x) (ADT7470_REG_TEMP_LIMITS_BASE_ADDR + ((x) * 2))
#define ADT7470_TEMP_MAX_REG(x) (ADT7470_REG_TEMP_LIMITS_BASE_ADDR + \
				((x) * 2) + 1)

#define ADT7470_FAN_COUNT	4
#define ADT7470_REG_FAN(x)	(ADT7470_REG_FAN_BASE_ADDR + ((x) * 2))
#define ADT7470_REG_FAN_MIN(x)	(ADT7470_REG_FAN_MIN_BASE_ADDR + ((x) * 2))
#define ADT7470_REG_FAN_MAX(x)	(ADT7470_REG_FAN_MAX_BASE_ADDR + ((x) * 2))

#define ADT7470_PWM_COUNT	4
#define ADT7470_REG_PWM(x)	(ADT7470_REG_PWM_BASE_ADDR + (x))
#define ADT7470_REG_PWM_MAX(x)	(ADT7470_REG_PWM_MAX_BASE_ADDR + (x))
#define ADT7470_REG_PWM_MIN(x)	(ADT7470_REG_PWM_MIN_BASE_ADDR + (x))
#define ADT7470_REG_PWM_TMIN(x)	(ADT7470_REG_PWM_TEMP_MIN_BASE_ADDR + (x))
#define ADT7470_REG_PWM_CFG(x)	(ADT7470_REG_PWM_CFG_BASE_ADDR + ((x) / 2))
#define ADT7470_REG_PWM_AUTO_TEMP(x)	(ADT7470_REG_PWM_AUTO_TEMP_BASE_ADDR + \
					((x) / 2))

#define ALARM2(x)		((x) << 8)

#define ADT7470_VENDOR		0x41
#define ADT7470_DEVICE		0x70
/* datasheet only mentions a revision 2 */
#define ADT7470_REVISION	0x02

/* "all temps" according to hwmon sysfs interface spec */
#define ADT7470_PWM_ALL_TEMPS	0x3FF

/* How often do we reread sensors values? (In jiffies) */
#define SENSOR_REFRESH_INTERVAL	(5 * HZ)

/* How often do we reread sensor limit values? (In jiffies) */
#define LIMIT_REFRESH_INTERVAL	(60 * HZ)

/* Wait at least 200ms per sensor for 10 sensors */
#define TEMP_COLLECTION_TIME	2000

/* auto update thing won't fire more than every 2s */
#define AUTO_UPDATE_INTERVAL	2000

/* datasheet says to divide this number by the fan reading to get fan rpm */
#define FAN_PERIOD_TO_RPM(x)	((90000 * 60) / (x))
#define FAN_RPM_TO_PERIOD	FAN_PERIOD_TO_RPM
#define FAN_PERIOD_INVALID	65535
#define FAN_DATA_VALID(x)	((x) && (x) != FAN_PERIOD_INVALID)

struct adt7470_data {
	struct device		*hwmon_dev;
	struct attribute_group	attrs;
	struct mutex		lock;
	char			sensors_valid;
	char			limits_valid;
	unsigned long		sensors_last_updated;	/* In jiffies */
	unsigned long		limits_last_updated;	/* In jiffies */

	int