[linux.git] / drivers / hwmon / tmp421.c

/* tmp421.c
 *
 * Copyright (C) 2009 Andre Prendel <[email protected]>
 * 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 const unsigned short normal_i2c[] = { 0x2a, 0x4c, 0x4d, 0x4e, 0x4f,
					     I2C_CLIENT_END };

enum chips { 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", 2 },
	{ "tmp422", 3 },
	{ "tmp423", 4 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tmp421_id);

struct tmp421_data {
	struct device *hwmon_dev;
	struct mutex update_lock;
	char valid;
	unsigned long last_updated;
	int channels;
	u8 config;
	s16 temp[4];
};

static int temp_from_s16(s16 reg)
{
	/* Mask out status bits */
	int temp = reg & ~0xf;

	return (temp * 1000 + 128) / 256;
}

static int temp_from_u16(u16 reg)
{
	/* Mask out status bits */
	int temp = reg & ~0xf;

	/* 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->channels; 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 umode_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 (index < data->channels)
		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,
			 struct i2c_board_info *info)
{
	enum chips kind;
	struct i2c_adapter *adapter = client->adapter;
	const char *names[] = { "TMP421", "TMP422", "TMP423" };
	u8 reg;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		return -ENODEV;

	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].name, I2C_NAME_SIZE);
	dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n",
		 names[kind], 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->channels = 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:
	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);

	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_list = normal_i2c,
};

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 <[email protected]>");
MODULE_DESCRIPTION("Texas Instruments TMP421/422/423 temperature sensor"
		   " driver");
MODULE_LICENSE("GPL");

module_init(tmp421_init);
module_exit(tmp421_exit);
Commit	Line	Data
9410700b AP	1	/* tmp421.c
	2	*
	3	* Copyright (C) 2009 Andre Prendel <[email protected]>
	4	* Preliminary support by:
	5	* Melvin Rook, Raymond Ng
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	20	*/
	21
	22	/*
	23	* Driver for the Texas Instruments TMP421 SMBus temperature sensor IC.
	24	* Supported models: TMP421, TMP422, TMP423
	25	*/
	26
	27	#include <linux/module.h>
	28	#include <linux/init.h>
	29	#include <linux/slab.h>
	30	#include <linux/jiffies.h>
	31	#include <linux/i2c.h>
	32	#include <linux/hwmon.h>
	33	#include <linux/hwmon-sysfs.h>
	34	#include <linux/err.h>
	35	#include <linux/mutex.h>
	36	#include <linux/sysfs.h>
	37
	38	/* Addresses to scan */
918ee91c JD	39	static const unsigned short normal_i2c[] = { 0x2a, 0x4c, 0x4d, 0x4e, 0x4f,
918ee91c JD	40	I2C_CLIENT_END };
9410700b	41
e5e9f44c	42	enum chips { tmp421, tmp422, tmp423 };
9410700b AP	43
	44	/* The TMP421 registers */
	45	#define TMP421_CONFIG_REG_1 0x09
	46	#define TMP421_CONVERSION_RATE_REG 0x0B
	47	#define TMP421_MANUFACTURER_ID_REG 0xFE
	48	#define TMP421_DEVICE_ID_REG 0xFF
	49
	50	static const u8 TMP421_TEMP_MSB[4] = { 0x00, 0x01, 0x02, 0x03 };
	51	static const u8 TMP421_TEMP_LSB[4] = { 0x10, 0x11, 0x12, 0x13 };
	52
	53	/* Flags */
	54	#define TMP421_CONFIG_SHUTDOWN 0x40
	55	#define TMP421_CONFIG_RANGE 0x04
	56
	57	/* Manufacturer / Device ID's */
	58	#define TMP421_MANUFACTURER_ID 0x55
	59	#define TMP421_DEVICE_ID 0x21
	60	#define TMP422_DEVICE_ID 0x22
	61	#define TMP423_DEVICE_ID 0x23
	62
	63	static const struct i2c_device_id tmp421_id[] = {
8d59582a JD	64	{ "tmp421", 2 },
	65	{ "tmp422", 3 },
	66	{ "tmp423", 4 },
9410700b AP	67	{ }
	68	};
	69	MODULE_DEVICE_TABLE(i2c, tmp421_id);
	70
	71	struct tmp421_data {
	72	struct device *hwmon_dev;
	73	struct mutex update_lock;
	74	char valid;
	75	unsigned long last_updated;
8d59582a	76	int channels;
9410700b AP	77	u8 config;
	78	s16 temp[4];
	79	};
	80
	81	static int temp_from_s16(s16 reg)
	82	{
a44908d7 JD	83	/* Mask out status bits */
a44908d7 JD	84	int temp = reg & ~0xf;
9410700b AP	85
	86	return (temp * 1000 + 128) / 256;
	87	}
	88
	89	static int temp_from_u16(u16 reg)
	90	{
a44908d7 JD	91	/* Mask out status bits */
a44908d7 JD	92	int temp = reg & ~0xf;
9410700b AP	93
	94	/* Add offset for extended temperature range. */
	95	temp -= 64 * 256;
	96
	97	return (temp * 1000 + 128) / 256;
	98	}
	99
	100	static struct tmp421_data tmp421_update_device(struct device dev)
	101	{
	102	struct i2c_client *client = to_i2c_client(dev);
	103	struct tmp421_data *data = i2c_get_clientdata(client);
	104	int i;
	105
	106	mutex_lock(&data->update_lock);
	107
	108	if (time_after(jiffies, data->last_updated + 2 * HZ) \|\| !data->valid) {
	109	data->config = i2c_smbus_read_byte_data(client,
	110	TMP421_CONFIG_REG_1);
	111
8d59582a	112	for (i = 0; i < data->channels; i++) {
9410700b AP	113	data->temp[i] = i2c_smbus_read_byte_data(client,
	114	TMP421_TEMP_MSB[i]) << 8;
	115	data->temp[i] \|= i2c_smbus_read_byte_data(client,
	116	TMP421_TEMP_LSB[i]);
	117	}
	118	data->last_updated = jiffies;
	119	data->valid = 1;
	120	}
	121
	122	mutex_unlock(&data->update_lock);
	123
	124	return data;
	125	}
	126
	127	static ssize_t show_temp_value(struct device *dev,
	128	struct device_attribute devattr, char buf)
	129	{
	130	int index = to_sensor_dev_attr(devattr)->index;
	131	struct tmp421_data *data = tmp421_update_device(dev);
	132	int temp;
	133
	134	mutex_lock(&data->update_lock);
	135	if (data->config & TMP421_CONFIG_RANGE)
	136	temp = temp_from_u16(data->temp[index]);
	137	else
	138	temp = temp_from_s16(data->temp[index]);
	139	mutex_unlock(&data->update_lock);
	140
	141	return sprintf(buf, "%d\n", temp);
	142	}
	143
	144	static ssize_t show_fault(struct device *dev,
	145	struct device_attribute devattr, char buf)
	146	{
	147	int index = to_sensor_dev_attr(devattr)->index;
	148	struct tmp421_data *data = tmp421_update_device(dev);
	149
	150	/*
	151	* The OPEN bit signals a fault. This is bit 0 of the temperature
	152	* register (low byte).
	153	*/
	154	if (data->temp[index] & 0x01)
	155	return sprintf(buf, "1\n");
	156	else
	157	return sprintf(buf, "0\n");
	158	}
	159
587a1f16	160	static umode_t tmp421_is_visible(struct kobject kobj, struct attribute a,
9410700b AP	161	int n)
	162	{
	163	struct device *dev = container_of(kobj, struct device, kobj);
	164	struct tmp421_data *data = dev_get_drvdata(dev);
	165	struct device_attribute *devattr;
	166	unsigned int index;
	167
	168	devattr = container_of(a, struct device_attribute, attr);
	169	index = to_sensor_dev_attr(devattr)->index;
	170
8d59582a	171	if (index < data->channels)
9410700b AP	172	return a->mode;
	173
	174	return 0;
	175	}
	176
	177	static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_value, NULL, 0);
	178	static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_value, NULL, 1);
	179	static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_fault, NULL, 1);
	180	static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp_value, NULL, 2);
	181	static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_fault, NULL, 2);
	182	static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp_value, NULL, 3);
	183	static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_fault, NULL, 3);
	184
	185	static struct attribute *tmp421_attr[] = {
	186	&sensor_dev_attr_temp1_input.dev_attr.attr,
	187	&sensor_dev_attr_temp2_input.dev_attr.attr,
	188	&sensor_dev_attr_temp2_fault.dev_attr.attr,
	189	&sensor_dev_attr_temp3_input.dev_attr.attr,
	190	&sensor_dev_attr_temp3_fault.dev_attr.attr,
	191	&sensor_dev_attr_temp4_input.dev_attr.attr,
	192	&sensor_dev_attr_temp4_fault.dev_attr.attr,
	193	NULL
	194	};
	195
	196	static const struct attribute_group tmp421_group = {
	197	.attrs = tmp421_attr,
	198	.is_visible = tmp421_is_visible,
	199	};
	200
	201	static int tmp421_init_client(struct i2c_client *client)
	202	{
	203	int config, config_orig;
	204
	205	/* Set the conversion rate to 2 Hz */
	206	i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05);
	207
	208	/* Start conversions (disable shutdown if necessary) */
	209	config = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_1);
	210	if (config < 0) {
	211	dev_err(&client->dev, "Could not read configuration"
	212	" register (%d)\n", config);
	213	return -ENODEV;
	214	}
	215
	216	config_orig = config;
	217	config &= ~TMP421_CONFIG_SHUTDOWN;
	218
	219	if (config != config_orig) {
	220	dev_info(&client->dev, "Enable monitoring chip\n");
	221	i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config);
	222	}
	223
	224	return 0;
	225	}
	226
310ec792	227	static int tmp421_detect(struct i2c_client *client,
9410700b AP	228	struct i2c_board_info *info)
9410700b AP	229	{
dbe73c8f	230	enum chips kind;
9410700b AP	231	struct i2c_adapter *adapter = client->adapter;
9410700b AP	232	const char *names[] = { "TMP421", "TMP422", "TMP423" };
dbe73c8f	233	u8 reg;
9410700b AP	234
	235	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
	236	return -ENODEV;
	237
dbe73c8f JD	238	reg = i2c_smbus_read_byte_data(client, TMP421_MANUFACTURER_ID_REG);
	239	if (reg != TMP421_MANUFACTURER_ID)
	240	return -ENODEV;
	241
	242	reg = i2c_smbus_read_byte_data(client, TMP421_DEVICE_ID_REG);
	243	switch (reg) {
	244	case TMP421_DEVICE_ID:
	245	kind = tmp421;
	246	break;
	247	case TMP422_DEVICE_ID:
	248	kind = tmp422;
	249	break;
	250	case TMP423_DEVICE_ID:
	251	kind = tmp423;
	252	break;
	253	default:
	254	return -ENODEV;
9410700b	255	}
dbe73c8f	256
dc71afe5	257	strlcpy(info->type, tmp421_id[kind].name, I2C_NAME_SIZE);
9410700b	258	dev_info(&adapter->dev, "Detected TI %s chip at 0x%02x\n",
dc71afe5	259	names[kind], client->addr);
9410700b AP	260
	261	return 0;
	262	}
	263
	264	static int tmp421_probe(struct i2c_client *client,
	265	const struct i2c_device_id *id)
	266	{
	267	struct tmp421_data *data;
	268	int err;
	269
	270	data = kzalloc(sizeof(struct tmp421_data), GFP_KERNEL);
	271	if (!data)
	272	return -ENOMEM;
	273
	274	i2c_set_clientdata(client, data);
	275	mutex_init(&data->update_lock);
8d59582a	276	data->channels = id->driver_data;
9410700b AP	277
	278	err = tmp421_init_client(client);
	279	if (err)
	280	goto exit_free;
	281
	282	err = sysfs_create_group(&client->dev.kobj, &tmp421_group);
	283	if (err)
	284	goto exit_free;
	285
	286	data->hwmon_dev = hwmon_device_register(&client->dev);
	287	if (IS_ERR(data->hwmon_dev)) {
	288	err = PTR_ERR(data->hwmon_dev);
	289	data->hwmon_dev = NULL;
	290	goto exit_remove;
	291	}
	292	return 0;
	293
	294	exit_remove:
	295	sysfs_remove_group(&client->dev.kobj, &tmp421_group);
	296
	297	exit_free:
9410700b AP	298	kfree(data);
	299
	300	return err;
	301	}
	302
	303	static int tmp421_remove(struct i2c_client *client)
	304	{
	305	struct tmp421_data *data = i2c_get_clientdata(client);
	306
	307	hwmon_device_unregister(data->hwmon_dev);
	308	sysfs_remove_group(&client->dev.kobj, &tmp421_group);
	309
9410700b AP	310	kfree(data);
	311
	312	return 0;
	313	}
	314
	315	static struct i2c_driver tmp421_driver = {
	316	.class = I2C_CLASS_HWMON,
	317	.driver = {
	318	.name = "tmp421",
	319	},
	320	.probe = tmp421_probe,
	321	.remove = tmp421_remove,
	322	.id_table = tmp421_id,
	323	.detect = tmp421_detect,
c3813d6a	324	.address_list = normal_i2c,
9410700b AP	325	};
	326
	327	static int __init tmp421_init(void)
	328	{
	329	return i2c_add_driver(&tmp421_driver);
	330	}
	331
	332	static void __exit tmp421_exit(void)
	333	{
	334	i2c_del_driver(&tmp421_driver);
	335	}
	336
	337	MODULE_AUTHOR("Andre Prendel <[email protected]>");
	338	MODULE_DESCRIPTION("Texas Instruments TMP421/422/423 temperature sensor"
	339	" driver");
	340	MODULE_LICENSE("GPL");
	341
	342	module_init(tmp421_init);
	343	module_exit(tmp421_exit);