Commit 9410700b authored by Andre Prendel's avatar Andre Prendel Committed by Jean Delvare
Browse files

hwmon: Add driver for Texas Instruments TMP421/422/423 sensor chips 



Add support for Texas Instruments TMP421/422/423 temperature sensor IC.

TI's TMP421/422/423 are I2C temperature sensor chips. These chips are
similar to TI's TMP401/411 chips, but with reduced functionality (only
temperature measurement). The chips have one local sensor and up to
three (TMP423) remote sensors.

Signed-off-by: default avatarAndre Prendel <andre.prendel@gmx.de>
Acked-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
parent 5bed13f5

drivers/hwmon/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -814,6 +814,16 @@ config SENSORS_TMP401 
	  This driver can also be built as a module.  If so, the module

	  will be called tmp401.



config SENSORS_TMP421

	tristate "Texas Instruments TMP421 and compatible"

	depends on I2C && EXPERIMENTAL

	help

	  If you say yes here you get support for Texas Instruments TMP421,

	  TMP422 and TMP423 temperature sensor chips.



	  This driver can also be built as a module.  If so, the module

	  will be called tmp421.



config SENSORS_VIA686A

	tristate "VIA686A"

	depends on PCI

drivers/hwmon/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -84,6 +84,7 @@ obj-$(CONFIG_SENSORS_SMSC47M1) += smsc47m1.o 
obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o

obj-$(CONFIG_SENSORS_THMC50)	+= thmc50.o

obj-$(CONFIG_SENSORS_TMP401)	+= tmp401.o

obj-$(CONFIG_SENSORS_TMP421)	+= tmp421.o

obj-$(CONFIG_SENSORS_VIA686A)	+= via686a.o

obj-$(CONFIG_SENSORS_VT1211)	+= vt1211.o

obj-$(CONFIG_SENSORS_VT8231)	+= vt8231.o

drivers/hwmon/tmp421.c

0 → 100644
+347 −0
Original line number Diff line number Diff line 
/* tmp421.c

 *

 * Copyright (C) 2009 Andre Prendel <andre.prendel@gmx.de>

 * Preliminary support by:

 * Melvin Rook, Raymond Ng

 *

 * 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.

 */



/*

 * Driver for the Texas Instruments TMP421 SMBus temperature sensor IC.

 * Supported models: TMP421, TMP422, TMP423

 */



#include <linux/module.h>

#include <linux/init.h>

#include <linux/slab.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/sysfs.h>



/* Addresses to scan */

static unsigned short normal_i2c[] = { 0x2a, 0x4c, 0x4d, 0x4e, 0x4f,

				       I2C_CLIENT_END };



/* Insmod parameters */

I2C_CLIENT_INSMOD_3(tmp421, tmp422, tmp423);



/* The TMP421 registers */

#define TMP421_CONFIG_REG_1			0x09

#define TMP421_CONVERSION_RATE_REG		0x0B

#define TMP421_MANUFACTURER_ID_REG		0xFE

#define TMP421_DEVICE_ID_REG			0xFF



static const u8 TMP421_TEMP_MSB[4]		= { 0x00, 0x01, 0x02, 0x03 };

static const u8 TMP421_TEMP_LSB[4]		= { 0x10, 0x11, 0x12, 0x13 };



/* Flags */

#define TMP421_CONFIG_SHUTDOWN			0x40

#define TMP421_CONFIG_RANGE			0x04



/* Manufacturer / Device ID's */

#define TMP421_MANUFACTURER_ID			0x55

#define TMP421_DEVICE_ID			0x21

#define TMP422_DEVICE_ID			0x22

#define TMP423_DEVICE_ID			0x23



static const struct i2c_device_id tmp421_id[] = {

	{ "tmp421", tmp421 },

	{ "tmp422", tmp422 },

	{ "tmp423", tmp423 },

	{ }

};

MODULE_DEVICE_TABLE(i2c, tmp421_id);



struct tmp421_data {

	struct device *hwmon_dev;

	struct mutex update_lock;

	char valid;

	unsigned long last_updated;

	int kind;

	u8 config;

	s16 temp[4];

};



static int temp_from_s16(s16 reg)

{

	int temp = reg;



	return (temp * 1000 + 128) / 256;

}



static int temp_from_u16(u16 reg)

{

	int temp = reg;



	/* Add offset for extended temperature range. */

	temp -= 64 * 256;



	return (temp * 1000 + 128) / 256;

}



static struct tmp421_data *tmp421_update_device(struct device *dev)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct tmp421_data *data = i2c_get_clientdata(client);

	int i;



	mutex_lock(&data->update_lock);



	if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {

		data->config = i2c_smbus_read_byte_data(client,

			TMP421_CONFIG_REG_1);



		for (i = 0; i <= data->kind; i++) {

			data->temp[i] = i2c_smbus_read_byte_data(client,

				TMP421_TEMP_MSB[i]) << 8;

			data->temp[i] |= i2c_smbus_read_byte_data(client,

				TMP421_TEMP_LSB[i]);

		}

		data->last_updated = jiffies;

		data->valid = 1;

	}



	mutex_unlock(&data->update_lock);



	return data;

}



static ssize_t show_temp_value(struct device *dev,

			       struct device_attribute *devattr, char *buf)

{

	int index = to_sensor_dev_attr(devattr)->index;

	struct tmp421_data *data = tmp421_update_device(dev);

	int temp;



	mutex_lock(&data->update_lock);

	if (data->config & TMP421_CONFIG_RANGE)

		temp = temp_from_u16(data->temp[index]);

	else

		temp = temp_from_s16(data->temp[index]);

	mutex_unlock(&data->update_lock);



	return sprintf(buf, "%d\n", temp);

}



static ssize_t show_fault(struct device *dev,

			  struct device_attribute *devattr, char *buf)

{

	int index = to_sensor_dev_attr(devattr)->index;

	struct tmp421_data *data = tmp421_update_device(dev);



	/*

	 * The OPEN bit signals a fault. This is bit 0 of the temperature

	 * register (low byte).

	 */

	if (data->temp[index] & 0x01)

		return sprintf(buf, "1\n");

	else

		return sprintf(buf, "0\n");

}



static mode_t tmp421_is_visible(struct kobject *kobj, struct attribute *a,

				int n)

{

	struct device *dev = container_of(kobj, struct device, kobj);

	struct tmp421_data *data = dev_get_drvdata(dev);

	struct device_attribute *devattr;

	unsigned int index;



	devattr = container_of(a, struct device_attribute, attr);

	index = to_sensor_dev_attr(devattr)->index;



	if (data->kind > index)

		return a->mode;



	return 0;

}



static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_value, NULL, 0);

static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_value, NULL, 1);

static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_fault, NULL, 1);

static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp_value, NULL, 2);

static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_fault, NULL, 2);

static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp_value, NULL, 3);

static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_fault, NULL, 3);



static struct attribute *tmp421_attr[] = {

	&sensor_dev_attr_temp1_input.dev_attr.attr,

	&sensor_dev_attr_temp2_input.dev_attr.attr,

	&sensor_dev_attr_temp2_fault.dev_attr.attr,

	&sensor_dev_attr_temp3_input.dev_attr.attr,

	&sensor_dev_attr_temp3_fault.dev_attr.attr,

	&sensor_dev_attr_temp4_input.dev_attr.attr,

	&sensor_dev_attr_temp4_fault.dev_attr.attr,

	NULL

};



static const struct attribute_group tmp421_group = {

	.attrs = tmp421_attr,

	.is_visible = tmp421_is_visible,

};



static int tmp421_init_client(struct i2c_client *client)

{

	int config, config_orig;



	/* Set the conversion rate to 2 Hz */

	i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05);



	/* Start conversions (disable shutdown if necessary) */

	config = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);

	if (config < 0) {

		dev_err(&client->dev, "Could not read configuration"

			 " register (%d)\n", config);

		return -ENODEV;

	}



	config_orig = config;

	config &= ~TMP421_CONFIG_SHUTDOWN;



	if (config != config_orig) {

		dev_info(&client->dev, "Enable monitoring chip\n");

		i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config);

	}



	return 0;

}



static int tmp421_detect(struct i2c_client *client, int kind,

			 struct i2c_board_info *info)

{

	struct i2c_adapter *adapter = client->adapter;

	const char *names[] = { "TMP421", "TMP422", "TMP423" };



	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))

		return -ENODEV;



	if (kind <= 0) {

		u8 reg;



		reg = i2c_smbus_read_byte_data(client,

					       TMP421_MANUFACTURER_ID_REG);

		if (reg != TMP421_MANUFACTURER_ID)

			return -ENODEV;



		reg = i2c_smbus_read_byte_data(client,

					       TMP421_DEVICE_ID_REG);

		switch (reg) {

		case TMP421_DEVICE_ID:

			kind = tmp421;

			break;

		case TMP422_DEVICE_ID:

			kind = tmp422;

			break;

		case TMP423_DEVICE_ID:

			kind = tmp423;

			break;

		default:

			return -ENODEV;

		}

	}

	strlcpy(info->type, tmp421_id[kind - 1].name, I2C_NAME_SIZE);

	dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n",

		 names[kind - 1], client->addr);



	return 0;

}



static int tmp421_probe(struct i2c_client *client,

			const struct i2c_device_id *id)

{

	struct tmp421_data *data;

	int err;



	data = kzalloc(sizeof(struct tmp421_data), GFP_KERNEL);

	if (!data)

		return -ENOMEM;



	i2c_set_clientdata(client, data);

	mutex_init(&data->update_lock);

	data->kind = id->driver_data;



	err = tmp421_init_client(client);

	if (err)

		goto exit_free;



	err = sysfs_create_group(&client->dev.kobj, &tmp421_group);

	if (err)

		goto exit_free;



	data->hwmon_dev = hwmon_device_register(&client->dev);

	if (IS_ERR(data->hwmon_dev)) {

		err = PTR_ERR(data->hwmon_dev);

		data->hwmon_dev = NULL;

		goto exit_remove;

	}

	return 0;



exit_remove:

	sysfs_remove_group(&client->dev.kobj, &tmp421_group);



exit_free:

	i2c_set_clientdata(client, NULL);

	kfree(data);



	return err;

}



static int tmp421_remove(struct i2c_client *client)

{

	struct tmp421_data *data = i2c_get_clientdata(client);



	hwmon_device_unregister(data->hwmon_dev);

	sysfs_remove_group(&client->dev.kobj, &tmp421_group);



	i2c_set_clientdata(client, NULL);

	kfree(data);



	return 0;

}



static struct i2c_driver tmp421_driver = {

	.class = I2C_CLASS_HWMON,

	.driver = {

		.name	= "tmp421",

	},

	.probe = tmp421_probe,

	.remove = tmp421_remove,

	.id_table = tmp421_id,

	.detect = tmp421_detect,

	.address_data = &addr_data,

};



static int __init tmp421_init(void)

{

	return i2c_add_driver(&tmp421_driver);

}



static void __exit tmp421_exit(void)

{

	i2c_del_driver(&tmp421_driver);

}



MODULE_AUTHOR("Andre Prendel <andre.prendel@gmx.de>");

MODULE_DESCRIPTION("Texas Instruments TMP421/422/423 temperature sensor"

		   " driver");

MODULE_LICENSE("GPL");



module_init(tmp421_init);

module_exit(tmp421_exit);

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