adt7470.c

linux 内核源代码

/*
 * A hwmon driver for the Analog Devices ADT7470
 * Copyright (C) 2007 IBM
 *
 * Author: Darrick J. Wong <[e-mail]>
 *
 * 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
 */

#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>

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

/* Insmod parameters */
I2C_CLIENT_INSMOD_1(adt7470);

/* 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_REG_ALARM2			0x42
#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_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 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)

/* sleep 1s while gathering temperature data */
#define TEMP_COLLECTION_TIME	1000

#define power_of_2(x)	(((x) & ((x) - 1)) == 0)

/* 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 i2c_client	client;
	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 */

	s8			temp[ADT7470_TEMP_COUNT];
	s8			temp_min[ADT7470_TEMP_COUNT];
	s8			temp_max[ADT7470_TEMP_COUNT];
	u16			fan[ADT7470_FAN_COUNT];
	u16			fan_min[ADT7470_FAN_COUNT];
	u16			fan_max[ADT7470_FAN_COUNT];
	u16			alarms, alarms_mask;
	u8			force_pwm_max;
	u8			pwm[ADT7470_PWM_COUNT];
	u8			pwm_max[ADT7470_PWM_COUNT];
	u8			pwm_automatic[ADT7470_PWM_COUNT];
	u8			pwm_min[ADT7470_PWM_COUNT];
	s8			pwm_tmin[ADT7470_PWM_COUNT];
	u8			pwm_auto_temp[ADT7470_PWM_COUNT];
};

static int adt7470_attach_adapter(struct i2c_adapter *adapter);
static int adt7470_detect(struct i2c_adapter *adapter, int address, int kind);
static int adt7470_detach_client(struct i2c_client *client);

static struct i2c_driver adt7470_driver = {
	.driver = {
		.name	= "adt7470",
	},
	.attach_adapter	= adt7470_attach_adapter,
	.detach_client	= adt7470_detach_client,
};

/*
 * 16-bit registers on the ADT7470 are low-byte first.  The data sheet says
 * that the low byte must be read before the high byte.
 */
static inline int adt7470_read_word_data(struct i2c_client *client, u8 reg)
{
	u16 foo;
	foo = i2c_smbus_read_byte_data(client, reg);
	foo |= ((u16)i2c_smbus_read_byte_data(client, reg + 1) << 8);
	return foo;
}

static inline int adt7470_write_word_data(struct i2c_client *client, u8 reg,
					  u16 value)
{
	return i2c_smbus_write_byte_data(client, reg, value & 0xFF)
	       && i2c_smbus_write_byte_data(client, reg + 1, value >> 8);
}

static void adt7470_init_client(struct i2c_client *client)
{
	int reg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);

	if (reg < 0) {
		dev_err(&client->dev, "cannot read configuration register\n");
	} else {
		/* start monitoring (and do a self-test) */
		i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, reg | 3);
	}
}

static struct adt7470_data *adt7470_update_device(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct adt7470_data *data = i2c_get_clientdata(client);
	unsigned long local_jiffies = jiffies;
	u8 cfg;
	int i;

	mutex_lock(&data->lock);
	if (time_before(local_jiffies, data->sensors_last_updated +
		SENSOR_REFRESH_INTERVAL)
		&& data->sensors_valid)
		goto no_sensor_update;

	/* start reading temperature sensors */
	cfg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
	cfg |= 0x80;
	i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, cfg);

	/*
	 * Delay is 200ms * number of tmp05 sensors.  Too bad
	 * there's no way to figure out how many are connected.
	 * For now, assume 1s will work.
	 */
	msleep(TEMP_COLLECTION_TIME);

	/* done reading temperature sensors */
	cfg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
	cfg &= ~0x80;
	i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, cfg);

	for (i = 0; i < ADT7470_TEMP_COUNT; i++)
		data->temp[i] = i2c_smbus_read_byte_data(client,
						ADT7470_TEMP_REG(i));

	for (i = 0; i < ADT7470_FAN_COUNT; i++)
		data->fan[i] = adt7470_read_word_data(client,
						ADT7470_REG_FAN(i));

	for (i = 0; i < ADT7470_PWM_COUNT; i++) {
		int reg;
		int reg_mask;

		data->pwm[i] = i2c_smbus_read_byte_data(client,
						ADT7470_REG_PWM(i));

		if (i % 2)
			reg_mask = ADT7470_PWM2_AUTO_MASK;
		else
			reg_mask = ADT7470_PWM1_AUTO_MASK;

		reg = ADT7470_REG_PWM_CFG(i);
		if (i2c_smbus_read_byte_data(client, reg) & reg_mask)
			data->pwm_automatic[i] = 1;
		else
			data->pwm_automatic[i] = 0;

		reg = ADT7470_REG_PWM_AUTO_TEMP(i);
		cfg = i2c_smbus_read_byte_data(client, reg);
		if (!(i % 2))
			data->pwm_auto_temp[i] = cfg >> 4;
		else
			data->pwm_auto_temp[i] = cfg & 0xF;
	}

	if (i2c_smbus_read_byte_data(client, ADT7470_REG_CFG) &
	    ADT7470_FSPD_MASK)
		data->force_pwm_max = 1;
	else
		data->force_pwm_max = 0;

	data->alarms = adt7470_read_word_data(client, ADT7470_REG_ALARM1);
	data->alarms_mask = adt7470_read_word_data(client,
						   ADT7470_REG_ALARM1_MASK);

	data->sensors_last_updated = local_jiffies;
	data->sensors_valid = 1;

no_sensor_update:
	if (time_before(local_jiffies, data->limits_last_updated +
		LIMIT_REFRESH_INTERVAL)
		&& data->limits_valid)
		goto out;

	for (i = 0; i < ADT7470_TEMP_COUNT; i++) {
		data->temp_min[i] = i2c_smbus_read_byte_data(client,
						ADT7470_TEMP_MIN_REG(i));
		data->temp_max[i] = i2c_smbus_read_byte_data(client,
						ADT7470_TEMP_MAX_REG(i));
	}

	for (i = 0; i < ADT7470_FAN_COUNT; i++) {
		data->fan_min[i] = adt7470_read_word_data(client,
						ADT7470_REG_FAN_MIN(i));
		data->fan_max[i] = adt7470_read_word_data(client,
						ADT7470_REG_FAN_MAX(i));
	}

	for (i = 0; i < ADT7470_PWM_COUNT; i++) {
		data->pwm_max[i] = i2c_smbus_read_byte_data(client,
						ADT7470_REG_PWM_MAX(i));
		data->pwm_min[i] = i2c_smbus_read_byte_data(client,
						ADT7470_REG_PWM_MIN(i));
		data->pwm_tmin[i] = i2c_smbus_read_byte_data(client,
						ADT7470_REG_PWM_TMIN(i));
	}

	data->limits_last_updated = local_jiffies;
	data->limits_valid = 1;

out:
	mutex_unlock(&data->lock);
	return data;
}

static ssize_t show_temp_min(struct device *dev,
			     struct device_attribute *devattr,
			     char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct adt7470_data *data = adt7470_update_device(dev);
	return sprintf(buf, "%d\n", 1000 * data->temp_min[attr->index]);
}

static ssize_t set_temp_min(struct device *dev,
			    struct device_attribute *devattr,
			    const char *buf,
			    size_t count)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct i2c_client *client = to_i2c_client(dev);
	struct adt7470_data *data = i2c_get_clientdata(client);
	int temp = simple_strtol(buf, NULL, 10) / 1000;

	mutex_lock(&data->lock);
	data->temp_min[attr->index] = temp;
	i2c_smbus_write_byte_data(client, ADT7470_TEMP_MIN_REG(attr->index),
				  temp);
	mutex_unlock(&data->lock);

	return count;
}

static ssize_t show_temp_max(struct device *dev,
			     struct device_attribute *devattr,
			     char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct adt7470_data *data = adt7470_update_device(dev);
	return sprintf(buf, "%d\n", 1000 * data->temp_max[attr->index]);
}

static ssize_t set_temp_max(struct device *dev,
			    struct device_attribute *devattr,
			    const char *buf,
			    size_t count)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);