[mirror_ubuntu-artful-kernel.git] / drivers / hwmon / tmp102.c

/* Texas Instruments TMP102 SMBus temperature sensor driver
 *
 * Copyright (C) 2010 Steven King <sfking@fdwdc.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., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/device.h>

#define	DRIVER_NAME "tmp102"

#define	TMP102_TEMP_REG			0x00
#define	TMP102_CONF_REG			0x01
/* note: these bit definitions are byte swapped */
#define		TMP102_CONF_SD		0x0100
#define		TMP102_CONF_TM		0x0200
#define		TMP102_CONF_POL		0x0400
#define		TMP102_CONF_F0		0x0800
#define		TMP102_CONF_F1		0x1000
#define		TMP102_CONF_R0		0x2000
#define		TMP102_CONF_R1		0x4000
#define		TMP102_CONF_OS		0x8000
#define		TMP102_CONF_EM		0x0010
#define		TMP102_CONF_AL		0x0020
#define		TMP102_CONF_CR0		0x0040
#define		TMP102_CONF_CR1		0x0080
#define	TMP102_TLOW_REG			0x02
#define	TMP102_THIGH_REG		0x03

struct tmp102 {
	struct device *hwmon_dev;
	struct mutex lock;
	u16 config_orig;
	unsigned long last_update;
	int temp[3];
};

/* convert left adjusted 13-bit TMP102 register value to milliCelsius */
static inline int tmp102_reg_to_mC(s16 val)
{
	return ((val & ~0x01) * 1000) / 128;
}

/* convert milliCelsius to left adjusted 13-bit TMP102 register value */
static inline u16 tmp102_mC_to_reg(int val)
{
	return (val * 128) / 1000;
}

static const u8 tmp102_reg[] = {
	TMP102_TEMP_REG,
	TMP102_TLOW_REG,
	TMP102_THIGH_REG,
};

static struct tmp102 *tmp102_update_device(struct i2c_client *client)
{
	struct tmp102 *tmp102 = i2c_get_clientdata(client);

	mutex_lock(&tmp102->lock);
	if (time_after(jiffies, tmp102->last_update + HZ / 3)) {
		int i;
		for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) {
			int status = i2c_smbus_read_word_swapped(client,
								 tmp102_reg[i]);
			if (status > -1)
				tmp102->temp[i] = tmp102_reg_to_mC(status);
		}
		tmp102->last_update = jiffies;
	}
	mutex_unlock(&tmp102->lock);
	return tmp102;
}

static ssize_t tmp102_show_temp(struct device *dev,
				struct device_attribute *attr,
				char *buf)
{
	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
	struct tmp102 *tmp102 = tmp102_update_device(to_i2c_client(dev));

	return sprintf(buf, "%d\n", tmp102->temp[sda->index]);
}

static ssize_t tmp102_set_temp(struct device *dev,
			       struct device_attribute *attr,
			       const char *buf, size_t count)
{
	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
	struct i2c_client *client = to_i2c_client(dev);
	struct tmp102 *tmp102 = i2c_get_clientdata(client);
	long val;
	int status;

	if (kstrtol(buf, 10, &val) < 0)
		return -EINVAL;
	val = SENSORS_LIMIT(val, -256000, 255000);

	mutex_lock(&tmp102->lock);
	tmp102->temp[sda->index] = val;
	status = i2c_smbus_write_word_swapped(client, tmp102_reg[sda->index],
					      tmp102_mC_to_reg(val));
	mutex_unlock(&tmp102->lock);
	return status ? : count;
}

static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0);

static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp,
			  tmp102_set_temp, 1);

static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp,
			  tmp102_set_temp, 2);

static struct attribute *tmp102_attributes[] = {
	&sensor_dev_attr_temp1_input.dev_attr.attr,
	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
	&sensor_dev_attr_temp1_max.dev_attr.attr,
	NULL
};

static const struct attribute_group tmp102_attr_group = {
	.attrs = tmp102_attributes,
};

#define TMP102_CONFIG  (TMP102_CONF_TM | TMP102_CONF_EM | TMP102_CONF_CR1)
#define TMP102_CONFIG_RD_ONLY (TMP102_CONF_R0 | TMP102_CONF_R1 | TMP102_CONF_AL)

static int __devinit tmp102_probe(struct i2c_client *client,
				  const struct i2c_device_id *id)
{
	struct tmp102 *tmp102;
	int status;

	if (!i2c_check_functionality(client->adapter,
				     I2C_FUNC_SMBUS_WORD_DATA)) {
		dev_err(&client->dev, "adapter doesn't support SMBus word "
			"transactions\n");
		return -ENODEV;
	}

	tmp102 = kzalloc(sizeof(*tmp102), GFP_KERNEL);
	if (!tmp102) {
		dev_dbg(&client->dev, "kzalloc failed\n");
		return -ENOMEM;
	}
	i2c_set_clientdata(client, tmp102);

	status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
	if (status < 0) {
		dev_err(&client->dev, "error reading config register\n");
		goto fail_free;
	}
	tmp102->config_orig = status;
	status = i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
					      TMP102_CONFIG);
	if (status < 0) {
		dev_err(&client->dev, "error writing config register\n");
		goto fail_restore_config;
	}
	status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
	if (status < 0) {
		dev_err(&client->dev, "error reading config register\n");
		goto fail_restore_config;
	}
	status &= ~TMP102_CONFIG_RD_ONLY;
	if (status != TMP102_CONFIG) {
		dev_err(&client->dev, "config settings did not stick\n");
		status = -ENODEV;
		goto fail_restore_config;
	}
	tmp102->last_update = jiffies - HZ;
	mutex_init(&tmp102->lock);

	status = sysfs_create_group(&client->dev.kobj, &tmp102_attr_group);
	if (status) {
		dev_dbg(&client->dev, "could not create sysfs files\n");
		goto fail_restore_config;
	}
	tmp102->hwmon_dev = hwmon_device_register(&client->dev);
	if (IS_ERR(tmp102->hwmon_dev)) {
		dev_dbg(&client->dev, "unable to register hwmon device\n");
		status = PTR_ERR(tmp102->hwmon_dev);
		goto fail_remove_sysfs;
	}

	dev_info(&client->dev, "initialized\n");

	return 0;

fail_remove_sysfs:
	sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
fail_restore_config:
	i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
				     tmp102->config_orig);
fail_free:
	kfree(tmp102);

	return status;
}

static int __devexit tmp102_remove(struct i2c_client *client)
{
	struct tmp102 *tmp102 = i2c_get_clientdata(client);

	hwmon_device_unregister(tmp102->hwmon_dev);
	sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);

	/* Stop monitoring if device was stopped originally */
	if (tmp102->config_orig & TMP102_CONF_SD) {
		int config;

		config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
		if (config >= 0)
			i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
						     config | TMP102_CONF_SD);
	}

	kfree(tmp102);

	return 0;
}

#ifdef CONFIG_PM
static int tmp102_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	int config;

	config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
	if (config < 0)
		return config;

	config |= TMP102_CONF_SD;
	return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
}

static int tmp102_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	int config;

	config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
	if (config < 0)
		return config;

	config &= ~TMP102_CONF_SD;
	return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
}

static const struct dev_pm_ops tmp102_dev_pm_ops = {
	.suspend	= tmp102_suspend,
	.resume		= tmp102_resume,
};

#define TMP102_DEV_PM_OPS (&tmp102_dev_pm_ops)
#else
#define	TMP102_DEV_PM_OPS NULL
#endif /* CONFIG_PM */

static const struct i2c_device_id tmp102_id[] = {
	{ "tmp102", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tmp102_id);

static struct i2c_driver tmp102_driver = {
	.driver.name	= DRIVER_NAME,
	.driver.pm	= TMP102_DEV_PM_OPS,
	.probe		= tmp102_probe,
	.remove		= __devexit_p(tmp102_remove),
	.id_table	= tmp102_id,
};

module_i2c_driver(tmp102_driver);

MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
cff37c9e	1	/* Texas Instruments TMP102 SMBus temperature sensor driver
beb1b6bb	2	*
cff37c9e	3	* Copyright (C) 2010 Steven King <sfking@fdwdc.com>
beb1b6bb SK	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License as published by
	7	* the Free Software Foundation; either version 2 of the License, or
	8	* (at your option) any later version.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA
	18	*/
	19
beb1b6bb SK	20	#include <linux/module.h>
	21	#include <linux/init.h>
	22	#include <linux/slab.h>
	23	#include <linux/i2c.h>
	24	#include <linux/hwmon.h>
	25	#include <linux/hwmon-sysfs.h>
	26	#include <linux/err.h>
	27	#include <linux/mutex.h>
cff37c9e	28	#include <linux/device.h>
beb1b6bb SK	29
	30	#define DRIVER_NAME "tmp102"
	31
	32	#define TMP102_TEMP_REG 0x00
	33	#define TMP102_CONF_REG 0x01
	34	/* note: these bit definitions are byte swapped */
	35	#define TMP102_CONF_SD 0x0100
	36	#define TMP102_CONF_TM 0x0200
	37	#define TMP102_CONF_POL 0x0400
	38	#define TMP102_CONF_F0 0x0800
	39	#define TMP102_CONF_F1 0x1000
	40	#define TMP102_CONF_R0 0x2000
	41	#define TMP102_CONF_R1 0x4000
	42	#define TMP102_CONF_OS 0x8000
	43	#define TMP102_CONF_EM 0x0010
	44	#define TMP102_CONF_AL 0x0020
	45	#define TMP102_CONF_CR0 0x0040
	46	#define TMP102_CONF_CR1 0x0080
	47	#define TMP102_TLOW_REG 0x02
	48	#define TMP102_THIGH_REG 0x03
	49
	50	struct tmp102 {
	51	struct device *hwmon_dev;
	52	struct mutex lock;
38806bda	53	u16 config_orig;
beb1b6bb SK	54	unsigned long last_update;
	55	int temp[3];
	56	};
	57
cff37c9e JD	58	/* convert left adjusted 13-bit TMP102 register value to milliCelsius */
cff37c9e JD	59	static inline int tmp102_reg_to_mC(s16 val)
beb1b6bb	60	{
cff37c9e	61	return ((val & ~0x01) * 1000) / 128;
beb1b6bb SK	62	}
beb1b6bb SK	63
cff37c9e JD	64	/* convert milliCelsius to left adjusted 13-bit TMP102 register value */
cff37c9e JD	65	static inline u16 tmp102_mC_to_reg(int val)
beb1b6bb SK	66	{
	67	return (val * 128) / 1000;
	68	}
	69
	70	static const u8 tmp102_reg[] = {
	71	TMP102_TEMP_REG,
	72	TMP102_TLOW_REG,
	73	TMP102_THIGH_REG,
	74	};
	75
	76	static struct tmp102 tmp102_update_device(struct i2c_client client)
	77	{
	78	struct tmp102 *tmp102 = i2c_get_clientdata(client);
	79
	80	mutex_lock(&tmp102->lock);
cff37c9e	81	if (time_after(jiffies, tmp102->last_update + HZ / 3)) {
beb1b6bb SK	82	int i;
beb1b6bb SK	83	for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) {
90f4102c JD	84	int status = i2c_smbus_read_word_swapped(client,
90f4102c JD	85	tmp102_reg[i]);
beb1b6bb SK	86	if (status > -1)
	87	tmp102->temp[i] = tmp102_reg_to_mC(status);
	88	}
	89	tmp102->last_update = jiffies;
	90	}
	91	mutex_unlock(&tmp102->lock);
	92	return tmp102;
	93	}
	94
	95	static ssize_t tmp102_show_temp(struct device *dev,
	96	struct device_attribute *attr,
	97	char *buf)
	98	{
	99	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
	100	struct tmp102 *tmp102 = tmp102_update_device(to_i2c_client(dev));
	101
	102	return sprintf(buf, "%d\n", tmp102->temp[sda->index]);
	103	}
	104
	105	static ssize_t tmp102_set_temp(struct device *dev,
	106	struct device_attribute *attr,
	107	const char *buf, size_t count)
	108	{
	109	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
	110	struct i2c_client *client = to_i2c_client(dev);
	111	struct tmp102 *tmp102 = i2c_get_clientdata(client);
	112	long val;
cff37c9e	113	int status;
beb1b6bb	114
179c4fdb	115	if (kstrtol(buf, 10, &val) < 0)
beb1b6bb	116	return -EINVAL;
cff37c9e JD	117	val = SENSORS_LIMIT(val, -256000, 255000);
cff37c9e JD	118
beb1b6bb	119	mutex_lock(&tmp102->lock);
cff37c9e	120	tmp102->temp[sda->index] = val;
90f4102c JD	121	status = i2c_smbus_write_word_swapped(client, tmp102_reg[sda->index],
90f4102c JD	122	tmp102_mC_to_reg(val));
beb1b6bb SK	123	mutex_unlock(&tmp102->lock);
	124	return status ? : count;
	125	}
	126
	127	static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0);
	128
	129	static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR \| S_IRUGO, tmp102_show_temp,
	130	tmp102_set_temp, 1);
	131
	132	static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR \| S_IRUGO, tmp102_show_temp,
	133	tmp102_set_temp, 2);
	134
	135	static struct attribute *tmp102_attributes[] = {
	136	&sensor_dev_attr_temp1_input.dev_attr.attr,
	137	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
	138	&sensor_dev_attr_temp1_max.dev_attr.attr,
	139	NULL
	140	};
	141
	142	static const struct attribute_group tmp102_attr_group = {
	143	.attrs = tmp102_attributes,
	144	};
	145
	146	#define TMP102_CONFIG (TMP102_CONF_TM \| TMP102_CONF_EM \| TMP102_CONF_CR1)
	147	#define TMP102_CONFIG_RD_ONLY (TMP102_CONF_R0 \| TMP102_CONF_R1 \| TMP102_CONF_AL)
	148
	149	static int __devinit tmp102_probe(struct i2c_client *client,
	150	const struct i2c_device_id *id)
	151	{
	152	struct tmp102 *tmp102;
	153	int status;
	154
cff37c9e	155	if (!i2c_check_functionality(client->adapter,
beb1b6bb	156	I2C_FUNC_SMBUS_WORD_DATA)) {
25985edc	157	dev_err(&client->dev, "adapter doesn't support SMBus word "
cff37c9e	158	"transactions\n");
beb1b6bb SK	159	return -ENODEV;
	160	}
	161
	162	tmp102 = kzalloc(sizeof(*tmp102), GFP_KERNEL);
	163	if (!tmp102) {
	164	dev_dbg(&client->dev, "kzalloc failed\n");
	165	return -ENOMEM;
	166	}
	167	i2c_set_clientdata(client, tmp102);
	168
90f4102c	169	status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
38806bda JD	170	if (status < 0) {
	171	dev_err(&client->dev, "error reading config register\n");
	172	goto fail_free;
	173	}
	174	tmp102->config_orig = status;
90f4102c JD	175	status = i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
90f4102c JD	176	TMP102_CONFIG);
cff37c9e JD	177	if (status < 0) {
cff37c9e JD	178	dev_err(&client->dev, "error writing config register\n");
38806bda	179	goto fail_restore_config;
cff37c9e	180	}
90f4102c	181	status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
beb1b6bb	182	if (status < 0) {
cff37c9e	183	dev_err(&client->dev, "error reading config register\n");
38806bda	184	goto fail_restore_config;
beb1b6bb SK	185	}
	186	status &= ~TMP102_CONFIG_RD_ONLY;
	187	if (status != TMP102_CONFIG) {
cff37c9e JD	188	dev_err(&client->dev, "config settings did not stick\n");
cff37c9e JD	189	status = -ENODEV;
38806bda	190	goto fail_restore_config;
beb1b6bb SK	191	}
	192	tmp102->last_update = jiffies - HZ;
	193	mutex_init(&tmp102->lock);
	194
	195	status = sysfs_create_group(&client->dev.kobj, &tmp102_attr_group);
	196	if (status) {
	197	dev_dbg(&client->dev, "could not create sysfs files\n");
38806bda	198	goto fail_restore_config;
beb1b6bb SK	199	}
	200	tmp102->hwmon_dev = hwmon_device_register(&client->dev);
	201	if (IS_ERR(tmp102->hwmon_dev)) {
	202	dev_dbg(&client->dev, "unable to register hwmon device\n");
	203	status = PTR_ERR(tmp102->hwmon_dev);
38806bda	204	goto fail_remove_sysfs;
beb1b6bb SK	205	}
	206
	207	dev_info(&client->dev, "initialized\n");
	208
	209	return 0;
38806bda JD	210
38806bda JD	211	fail_remove_sysfs:
beb1b6bb	212	sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
38806bda	213	fail_restore_config:
90f4102c JD	214	i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
90f4102c JD	215	tmp102->config_orig);
38806bda	216	fail_free:
beb1b6bb SK	217	kfree(tmp102);
beb1b6bb SK	218
cff37c9e	219	return status;
beb1b6bb SK	220	}
	221
	222	static int __devexit tmp102_remove(struct i2c_client *client)
	223	{
	224	struct tmp102 *tmp102 = i2c_get_clientdata(client);
	225
beb1b6bb SK	226	hwmon_device_unregister(tmp102->hwmon_dev);
beb1b6bb SK	227	sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
38806bda JD	228
	229	/* Stop monitoring if device was stopped originally */
	230	if (tmp102->config_orig & TMP102_CONF_SD) {
	231	int config;
	232
90f4102c	233	config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
38806bda	234	if (config >= 0)
90f4102c JD	235	i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
90f4102c JD	236	config \| TMP102_CONF_SD);
38806bda JD	237	}
38806bda JD	238
beb1b6bb SK	239	kfree(tmp102);
	240
	241	return 0;
	242	}
	243
	244	#ifdef CONFIG_PM
	245	static int tmp102_suspend(struct device *dev)
	246	{
	247	struct i2c_client *client = to_i2c_client(dev);
8d4dee98	248	int config;
beb1b6bb	249
90f4102c	250	config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
8d4dee98 JD	251	if (config < 0)
8d4dee98 JD	252	return config;
beb1b6bb	253
8d4dee98	254	config \|= TMP102_CONF_SD;
90f4102c	255	return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
beb1b6bb SK	256	}
	257
	258	static int tmp102_resume(struct device *dev)
	259	{
	260	struct i2c_client *client = to_i2c_client(dev);
8d4dee98	261	int config;
beb1b6bb	262
90f4102c	263	config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
8d4dee98 JD	264	if (config < 0)
8d4dee98 JD	265	return config;
beb1b6bb	266
8d4dee98	267	config &= ~TMP102_CONF_SD;
90f4102c	268	return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
beb1b6bb SK	269	}
	270
	271	static const struct dev_pm_ops tmp102_dev_pm_ops = {
	272	.suspend = tmp102_suspend,
	273	.resume = tmp102_resume,
	274	};
	275
	276	#define TMP102_DEV_PM_OPS (&tmp102_dev_pm_ops)
	277	#else
	278	#define TMP102_DEV_PM_OPS NULL
	279	#endif /* CONFIG_PM */
	280
beb1b6bb	281	static const struct i2c_device_id tmp102_id[] = {
cff37c9e	282	{ "tmp102", 0 },
beb1b6bb SK	283	{ }
beb1b6bb SK	284	};
cff37c9e	285	MODULE_DEVICE_TABLE(i2c, tmp102_id);
beb1b6bb SK	286
	287	static struct i2c_driver tmp102_driver = {
	288	.driver.name = DRIVER_NAME,
	289	.driver.pm = TMP102_DEV_PM_OPS,
beb1b6bb SK	290	.probe = tmp102_probe,
	291	.remove = __devexit_p(tmp102_remove),
	292	.id_table = tmp102_id,
beb1b6bb SK	293	};
beb1b6bb SK	294
f0967eea	295	module_i2c_driver(tmp102_driver);
beb1b6bb	296
beb1b6bb SK	297	MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
	298	MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
	299	MODULE_LICENSE("GPL");