lm63.c

linux 内核源代码

/*
 * lm63.c - driver for the National Semiconductor LM63 temperature sensor
 *          with integrated fan control
 * Copyright (C) 2004-2006  Jean Delvare <[e-mail]>
 * 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>

/*
 * Addresses to scan
 * Address is fully defined internally and cannot be changed.
 */

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

/*
 * Insmod parameters
 */

I2C_CLIENT_INSMOD_1(lm63);

/*
 * The LM63 registers
 */

#define LM63_REG_CONFIG1		0x03
#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_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

/*
 * 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.
 */

#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 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 HYST_TO_REG(val)	((val) <= 0 ? 0 : \
				 (val) >= 127000 ? 127 : \
				 ((val) + 500) / 1000)

/*
 * Functions declaration
 */

static int lm63_attach_adapter(struct i2c_adapter *adapter);
static int lm63_detach_client(struct i2c_client *client);

static struct lm63_data *lm63_update_device(struct device *dev);

static int lm63_detect(struct i2c_adapter *adapter, int address, int kind);
static void lm63_init_client(struct i2c_client *client);

/*
 * Driver data (common to all clients)
 */

static struct i2c_driver lm63_driver = {
	.driver = {
		.name	= "lm63",
	},
	.attach_adapter	= lm63_attach_adapter,
	.detach_client	= lm63_detach_client,
};

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

struct lm63_data {
	struct i2c_client client;
	struct device *hwmon_dev;
	struct mutex update_lock;
	char valid; /* zero until following fields are valid */
	unsigned long last_updated; /* in jiffies */

	/* registers values */
	u8 config, config_fan;
	u16 fan[2];	/* 0: input
			   1: low limit */
	u8 pwm1_freq;
	u8 pwm1_value;
	s8 temp8[3];	/* 0: local input
			   1: local high limit
			   2: remote critical limit */
	s16 temp11[3];	/* 0: remote input
			   1: remote low limit
			   2: remote high limit */
	u8 temp2_crit_hyst;
	u8 alarms;
};

/*
 * Sysfs callback functions and files
 */

static ssize_t show_fan(struct device *dev, struct device_attribute *devattr,
			char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct lm63_data *data = lm63_update_device(dev);
	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index]));
}

static ssize_t set_fan(struct device *dev, struct device_attribute *dummy,
		       const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm63_data *data = i2c_get_clientdata(client);
	unsigned long val = simple_strtoul(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->fan[1] = FAN_TO_REG(val);
	i2c_smbus_write_byte_data(client, LM63_REG_TACH_LIMIT_LSB,
				  data->fan[1] & 0xFF);
	i2c_smbus_write_byte_data(client, LM63_REG_TACH_LIMIT_MSB,
				  data->fan[1] >> 8);
	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t show_pwm1(struct device *dev, struct device_attribute *dummy,
			 char *buf)
{
	struct lm63_data *data = lm63_update_device(dev);
	return sprintf(buf, "%d\n", data->pwm1_value >= 2 * data->pwm1_freq ?
		       255 : (data->pwm1_value * 255 + data->pwm1_freq) /
		       (2 * data->pwm1_freq));
}

static ssize_t set_pwm1(struct device *dev, struct device_attribute *dummy,
			const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm63_data *data = i2c_get_clientdata(client);
	unsigned long val;
	
	if (!(data->config_fan & 0x20)) /* register is read-only */
		return -EPERM;

	val = simple_strtoul(buf, NULL, 10);
	mutex_lock(&data->update_lock);
	data->pwm1_value = val <= 0 ? 0 :
			   val >= 255 ? 2 * data->pwm1_freq :
			   (val * data->pwm1_freq * 2 + 127) / 255;
	i2c_smbus_write_byte_data(client, LM63_REG_PWM_VALUE, data->pwm1_value);
	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t show_pwm1_enable(struct device *dev, struct device_attribute *dummy,
				char *buf)
{
	struct lm63_data *data = lm63_update_device(dev);
	return sprintf(buf, "%d\n", data->config_fan & 0x20 ? 1 : 2);
}

static ssize_t show_temp8(struct device *dev, struct device_attribute *devattr,
			  char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct lm63_data *data = lm63_update_device(dev);
	return sprintf(buf, "%d\n", TEMP8_FROM_REG(data->temp8[attr->index]));
}

static ssize_t set_temp8(struct device *dev, struct device_attribute *dummy,
			 const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm63_data *data = i2c_get_clientdata(client);
	long val = simple_strtol(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->temp8[1] = TEMP8_TO_REG(val);
	i2c_smbus_write_byte_data(client, LM63_REG_LOCAL_HIGH, data->temp8[1]);
	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t show_temp11(struct device *dev, struct device_attribute *devattr,
			   char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct lm63_data *data = lm63_update_device(dev);
	return sprintf(buf, "%d\n", TEMP11_FROM_REG(data->temp11[attr->index]));
}

static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr,
			  const char *buf, size_t count)
{
	static const u8 reg[4] = {
		LM63_REG_REMOTE_LOW_MSB,
		LM63_REG_REMOTE_LOW_LSB,
		LM63_REG_REMOTE_HIGH_MSB,
		LM63_REG_REMOTE_HIGH_LSB,
	};

	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct i2c_client *client = to_i2c_client(dev);
	struct lm63_data *data = i2c_get_clientdata(client);
	long val = simple_strtol(buf, NULL, 10);
	int nr = attr->index;

	mutex_lock(&data->update_lock);
	data->temp11[nr] = TEMP11_TO_REG(val);
	i2c_smbus_write_byte_data(client, reg[(nr - 1) * 2],
				  data->temp11[nr] >> 8);
	i2c_smbus_write_byte_data(client, reg[(nr - 1) * 2 + 1],
				  data->temp11[nr] & 0xff);
	mutex_unlock(&data->update_lock);
	return count;
}

/* Hysteresis register holds a relative value, while we want to present
   an absolute to user-space */
static ssize_t show_temp2_crit_hyst(struct device *dev, struct device_attribute *dummy,
				    char *buf)
{
	struct lm63_data *data = lm63_update_device(dev);
	return sprintf(buf, "%d\n", TEMP8_FROM_REG(data->temp8[2])
		       - TEMP8_FROM_REG(data->temp2_crit_hyst));
}

/* And now the other way around, user-space provides an absolute
   hysteresis value and we have to store a relative one */
static ssize_t set_temp2_crit_hyst(struct device *dev, struct device_attribute *dummy,
				   const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lm63_data *data = i2c_get_clientdata(client);
	long val = simple_strtol(buf, NULL, 10);
	long hyst;

	mutex_lock(&data->update_lock);
	hyst = TEMP8_FROM_REG(data->temp8[2]) - val;
	i2c_smbus_write_byte_data(client, LM63_REG_REMOTE_TCRIT_HYST,
				  HYST_TO_REG(hyst));
	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy,