[linux.git] / drivers / hwmon / w83l785ts.c

/*
 * w83l785ts.c - Part of lm_sensors, Linux kernel modules for hardware
 *               monitoring
 * Copyright (C) 2003-2009  Jean Delvare <[email protected]>
 *
 * Inspired from the lm83 driver. The W83L785TS-S is a sensor chip made
 * by Winbond. It reports a single external temperature with a 1 deg
 * resolution and a 3 deg accuracy. Datasheet can be obtained from
 * Winbond's website at:
 *   http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83L785TS-S.pdf
 *
 * Ported to Linux 2.6 by Wolfgang Ziegler <[email protected]> and Jean Delvare
 * <[email protected]>.
 *
 * Thanks to James Bolt <[email protected]> for benchmarking the read
 * error handling mechanism.
 *
 * 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/delay.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>

/* How many retries on register read error */
#define MAX_RETRIES	5

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

static const unsigned short normal_i2c[] = { 0x2e, I2C_CLIENT_END };

/*
 * The W83L785TS-S registers
 * Manufacturer ID is 0x5CA3 for Winbond.
 */

#define W83L785TS_REG_MAN_ID1		0x4D
#define W83L785TS_REG_MAN_ID2		0x4C
#define W83L785TS_REG_CHIP_ID		0x4E
#define W83L785TS_REG_CONFIG		0x40
#define W83L785TS_REG_TYPE		0x52
#define W83L785TS_REG_TEMP		0x27
#define W83L785TS_REG_TEMP_OVER		0x53 /* not sure about this one */

/*
 * Conversions
 * The W83L785TS-S uses signed 8-bit values.
 */

#define TEMP_FROM_REG(val)	((val) * 1000)

/*
 * Functions declaration
 */

static int w83l785ts_probe(struct i2c_client *client,
			   const struct i2c_device_id *id);
static int w83l785ts_detect(struct i2c_client *client,
			    struct i2c_board_info *info);
static int w83l785ts_remove(struct i2c_client *client);
static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval);
static struct w83l785ts_data *w83l785ts_update_device(struct device *dev);

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

static const struct i2c_device_id w83l785ts_id[] = {
	{ "w83l785ts", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, w83l785ts_id);

static struct i2c_driver w83l785ts_driver = {
	.class		= I2C_CLASS_HWMON,
	.driver = {
		.name	= "w83l785ts",
	},
	.probe		= w83l785ts_probe,
	.remove		= w83l785ts_remove,
	.id_table	= w83l785ts_id,
	.detect		= w83l785ts_detect,
	.address_list	= normal_i2c,
};

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

struct w83l785ts_data {
	struct device *hwmon_dev;
	struct mutex update_lock;
	char valid; /* zero until following fields are valid */
	unsigned long last_updated; /* in jiffies */

	/* registers values */
	s8 temp[2]; /* 0: input, 1: critical limit */
};

/*
 * Sysfs stuff
 */

static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
	char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct w83l785ts_data *data = w83l785ts_update_device(dev);
	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
}

static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL, 1);

/*
 * Real code
 */

/* Return 0 if detection is successful, -ENODEV otherwise */
static int w83l785ts_detect(struct i2c_client *client,
			    struct i2c_board_info *info)
{
	struct i2c_adapter *adapter = client->adapter;
	u16 man_id;
	u8 chip_id;

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

	/* detection */
	if ((w83l785ts_read_value(client, W83L785TS_REG_CONFIG, 0) & 0x80)
	 || (w83l785ts_read_value(client, W83L785TS_REG_TYPE, 0) & 0xFC)) {
		dev_dbg(&adapter->dev,
			"W83L785TS-S detection failed at 0x%02x\n",
			client->addr);
		return -ENODEV;
	}

	/* Identification */
	man_id = (w83l785ts_read_value(client, W83L785TS_REG_MAN_ID1, 0) << 8)
	       + w83l785ts_read_value(client, W83L785TS_REG_MAN_ID2, 0);
	chip_id = w83l785ts_read_value(client, W83L785TS_REG_CHIP_ID, 0);

	if (man_id != 0x5CA3		/* Winbond */
	 || chip_id != 0x70) {		/* W83L785TS-S */
		dev_dbg(&adapter->dev,
			"Unsupported chip (man_id=0x%04X, chip_id=0x%02X)\n",
			man_id, chip_id);
		return -ENODEV;
	}

	strlcpy(info->type, "w83l785ts", I2C_NAME_SIZE);

	return 0;
}

static int w83l785ts_probe(struct i2c_client *client,
			   const struct i2c_device_id *id)
{
	struct w83l785ts_data *data;
	struct device *dev = &client->dev;
	int err;

	data = devm_kzalloc(dev, sizeof(struct w83l785ts_data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	i2c_set_clientdata(client, data);
	data->valid = 0;
	mutex_init(&data->update_lock);

	/* Default values in case the first read fails (unlikely). */
	data->temp[1] = data->temp[0] = 0;

	/*
	 * Initialize the W83L785TS chip
	 * Nothing yet, assume it is already started.
	 */

	err = device_create_file(dev, &sensor_dev_attr_temp1_input.dev_attr);
	if (err)
		return err;

	err = device_create_file(dev, &sensor_dev_attr_temp1_max.dev_attr);
	if (err)
		goto exit_remove;

	/* Register sysfs hooks */
	data->hwmon_dev = hwmon_device_register(dev);
	if (IS_ERR(data->hwmon_dev)) {
		err = PTR_ERR(data->hwmon_dev);
		goto exit_remove;
	}

	return 0;

exit_remove:
	device_remove_file(dev, &sensor_dev_attr_temp1_input.dev_attr);
	device_remove_file(dev, &sensor_dev_attr_temp1_max.dev_attr);
	return err;
}

static int w83l785ts_remove(struct i2c_client *client)
{
	struct w83l785ts_data *data = i2c_get_clientdata(client);

	hwmon_device_unregister(data->hwmon_dev);
	device_remove_file(&client->dev,
			   &sensor_dev_attr_temp1_input.dev_attr);
	device_remove_file(&client->dev,
			   &sensor_dev_attr_temp1_max.dev_attr);

	return 0;
}

static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval)
{
	int value, i;
	struct device *dev;
	const char *prefix;

	/*
	 * We might be called during detection, at which point the client
	 * isn't yet fully initialized, so we can't use dev_dbg on it
	 */
	if (i2c_get_clientdata(client)) {
		dev = &client->dev;
		prefix = "";
	} else {
		dev = &client->adapter->dev;
		prefix = "w83l785ts: ";
	}

	/*
	 * Frequent read errors have been reported on Asus boards, so we
	 * retry on read errors. If it still fails (unlikely), return the
	 * default value requested by the caller.
	 */
	for (i = 1; i <= MAX_RETRIES; i++) {
		value = i2c_smbus_read_byte_data(client, reg);
		if (value >= 0) {
			dev_dbg(dev, "%sRead 0x%02x from register 0x%02x.\n",
				prefix, value, reg);
			return value;
		}
		dev_dbg(dev, "%sRead failed, will retry in %d.\n", prefix, i);
		msleep(i);
	}

	dev_err(dev, "%sCouldn't read value from register 0x%02x.\n", prefix,
		reg);
	return defval;
}

static struct w83l785ts_data *w83l785ts_update_device(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct w83l785ts_data *data = i2c_get_clientdata(client);

	mutex_lock(&data->update_lock);

	if (!data->valid || time_after(jiffies, data->last_updated + HZ * 2)) {
		dev_dbg(&client->dev, "Updating w83l785ts data.\n");
		data->temp[0] = w83l785ts_read_value(client,
				W83L785TS_REG_TEMP, data->temp[0]);
		data->temp[1] = w83l785ts_read_value(client,
				W83L785TS_REG_TEMP_OVER, data->temp[1]);

		data->last_updated = jiffies;
		data->valid = 1;
	}

	mutex_unlock(&data->update_lock);

	return data;
}

module_i2c_driver(w83l785ts_driver);

MODULE_AUTHOR("Jean Delvare <[email protected]>");
MODULE_DESCRIPTION("W83L785TS-S driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* w83l785ts.c - Part of lm_sensors, Linux kernel modules for hardware
	3	* monitoring
7c81c60f	4	* Copyright (C) 2003-2009 Jean Delvare <[email protected]>
1da177e4 LT	5	*
	6	* Inspired from the lm83 driver. The W83L785TS-S is a sensor chip made
	7	* by Winbond. It reports a single external temperature with a 1 deg
	8	* resolution and a 3 deg accuracy. Datasheet can be obtained from
	9	* Winbond's website at:
	10	* http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83L785TS-S.pdf
	11	*
	12	* Ported to Linux 2.6 by Wolfgang Ziegler <[email protected]> and Jean Delvare
7c81c60f	13	* <[email protected]>.
1da177e4 LT	14	*
	15	* Thanks to James Bolt <[email protected]> for benchmarking the read
	16	* error handling mechanism.
	17	*
	18	* This program is free software; you can redistribute it and/or modify
	19	* it under the terms of the GNU General Public License as published by
	20	* the Free Software Foundation; either version 2 of the License, or
	21	* (at your option) any later version.
	22	*
	23	* This program is distributed in the hope that it will be useful,
	24	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	25	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	26	* GNU General Public License for more details.
	27	*
	28	* You should have received a copy of the GNU General Public License
	29	* along with this program; if not, write to the Free Software
	30	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	31	*/
	32
1da177e4 LT	33	#include <linux/module.h>
	34	#include <linux/delay.h>
	35	#include <linux/init.h>
	36	#include <linux/slab.h>
	37	#include <linux/jiffies.h>
	38	#include <linux/i2c.h>
943b0830	39	#include <linux/hwmon.h>
709439a2	40	#include <linux/hwmon-sysfs.h>
943b0830	41	#include <linux/err.h>
9a61bf63	42	#include <linux/mutex.h>
1da177e4 LT	43
	44	/* How many retries on register read error */
	45	#define MAX_RETRIES 5
	46
	47	/*
	48	* Address to scan
	49	* Address is fully defined internally and cannot be changed.
	50	*/
	51
25e9c86d	52	static const unsigned short normal_i2c[] = { 0x2e, I2C_CLIENT_END };
1da177e4	53
1da177e4 LT	54	/*
	55	* The W83L785TS-S registers
	56	* Manufacturer ID is 0x5CA3 for Winbond.
	57	*/
	58
	59	#define W83L785TS_REG_MAN_ID1 0x4D
	60	#define W83L785TS_REG_MAN_ID2 0x4C
	61	#define W83L785TS_REG_CHIP_ID 0x4E
	62	#define W83L785TS_REG_CONFIG 0x40
	63	#define W83L785TS_REG_TYPE 0x52
	64	#define W83L785TS_REG_TEMP 0x27
	65	#define W83L785TS_REG_TEMP_OVER 0x53 /* not sure about this one */
	66
	67	/*
	68	* Conversions
	69	* The W83L785TS-S uses signed 8-bit values.
	70	*/
	71
cb929eae	72	#define TEMP_FROM_REG(val) ((val) * 1000)
1da177e4 LT	73
	74	/*
	75	* Functions declaration
	76	*/
	77
dc18a418 JD	78	static int w83l785ts_probe(struct i2c_client *client,
dc18a418 JD	79	const struct i2c_device_id *id);
310ec792	80	static int w83l785ts_detect(struct i2c_client *client,
dc18a418 JD	81	struct i2c_board_info *info);
dc18a418 JD	82	static int w83l785ts_remove(struct i2c_client *client);
1da177e4 LT	83	static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval);
	84	static struct w83l785ts_data w83l785ts_update_device(struct device dev);
	85
	86	/*
	87	* Driver data (common to all clients)
	88	*/
59965425	89
dc18a418	90	static const struct i2c_device_id w83l785ts_id[] = {
1f86df49	91	{ "w83l785ts", 0 },
dc18a418 JD	92	{ }
	93	};
	94	MODULE_DEVICE_TABLE(i2c, w83l785ts_id);
	95
1da177e4	96	static struct i2c_driver w83l785ts_driver = {
dc18a418	97	.class = I2C_CLASS_HWMON,
cdaf7934	98	.driver = {
cdaf7934 LR	99	.name = "w83l785ts",
cdaf7934 LR	100	},
dc18a418 JD	101	.probe = w83l785ts_probe,
	102	.remove = w83l785ts_remove,
	103	.id_table = w83l785ts_id,
	104	.detect = w83l785ts_detect,
c3813d6a	105	.address_list = normal_i2c,
1da177e4 LT	106	};
	107
	108	/*
	109	* Client data (each client gets its own)
	110	*/
	111
	112	struct w83l785ts_data {
1beeffe4	113	struct device *hwmon_dev;
9a61bf63	114	struct mutex update_lock;
1da177e4 LT	115	char valid; /* zero until following fields are valid */
	116	unsigned long last_updated; /* in jiffies */
	117
	118	/* registers values */
130067d7	119	s8 temp[2]; /* 0: input, 1: critical limit */
1da177e4 LT	120	};
	121
	122	/*
	123	* Sysfs stuff
	124	*/
	125
709439a2 JD	126	static ssize_t show_temp(struct device dev, struct device_attribute devattr,
709439a2 JD	127	char *buf)
1da177e4	128	{
709439a2	129	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
1da177e4	130	struct w83l785ts_data *data = w83l785ts_update_device(dev);
709439a2	131	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
1da177e4 LT	132	}
1da177e4 LT	133
709439a2 JD	134	static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
709439a2 JD	135	static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, NULL, 1);
1da177e4 LT	136
	137	/*
	138	* Real code
	139	*/
	140
dc18a418	141	/* Return 0 if detection is successful, -ENODEV otherwise */
310ec792	142	static int w83l785ts_detect(struct i2c_client *client,
dc18a418	143	struct i2c_board_info *info)
1da177e4	144	{
a1fa4cdc JD	145	struct i2c_adapter *adapter = client->adapter;
	146	u16 man_id;
	147	u8 chip_id;
1da177e4 LT	148
1da177e4 LT	149	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
dc18a418	150	return -ENODEV;
1da177e4	151
a1fa4cdc JD	152	/* detection */
	153	if ((w83l785ts_read_value(client, W83L785TS_REG_CONFIG, 0) & 0x80)
	154	\|\| (w83l785ts_read_value(client, W83L785TS_REG_TYPE, 0) & 0xFC)) {
	155	dev_dbg(&adapter->dev,
	156	"W83L785TS-S detection failed at 0x%02x\n",
	157	client->addr);
	158	return -ENODEV;
1da177e4 LT	159	}
1da177e4 LT	160
a1fa4cdc JD	161	/* Identification */
	162	man_id = (w83l785ts_read_value(client, W83L785TS_REG_MAN_ID1, 0) << 8)
	163	+ w83l785ts_read_value(client, W83L785TS_REG_MAN_ID2, 0);
	164	chip_id = w83l785ts_read_value(client, W83L785TS_REG_CHIP_ID, 0);
	165
	166	if (man_id != 0x5CA3 /* Winbond */
	167	\|\| chip_id != 0x70) { /* W83L785TS-S */
	168	dev_dbg(&adapter->dev,
	169	"Unsupported chip (man_id=0x%04X, chip_id=0x%02X)\n",
	170	man_id, chip_id);
	171	return -ENODEV;
1da177e4 LT	172	}
1da177e4 LT	173
dc18a418 JD	174	strlcpy(info->type, "w83l785ts", I2C_NAME_SIZE);
	175
	176	return 0;
	177	}
	178
f187fc04	179	static int w83l785ts_probe(struct i2c_client *client,
dc18a418 JD	180	const struct i2c_device_id *id)
	181	{
	182	struct w83l785ts_data *data;
f187fc04	183	struct device *dev = &client->dev;
e2730bea	184	int err;
dc18a418	185
e2730bea GR	186	data = devm_kzalloc(dev, sizeof(struct w83l785ts_data), GFP_KERNEL);
	187	if (!data)
	188	return -ENOMEM;
dc18a418	189
f187fc04	190	i2c_set_clientdata(client, data);
1da177e4	191	data->valid = 0;
9a61bf63	192	mutex_init(&data->update_lock);
1da177e4 LT	193
1da177e4 LT	194	/* Default values in case the first read fails (unlikely). */
709439a2	195	data->temp[1] = data->temp[0] = 0;
1da177e4	196
1da177e4 LT	197	/*
	198	* Initialize the W83L785TS chip
	199	* Nothing yet, assume it is already started.
	200	*/
	201
f187fc04	202	err = device_create_file(dev, &sensor_dev_attr_temp1_input.dev_attr);
ccc5c306	203	if (err)
e2730bea	204	return err;
ccc5c306	205
f187fc04	206	err = device_create_file(dev, &sensor_dev_attr_temp1_max.dev_attr);
ccc5c306 RM	207	if (err)
	208	goto exit_remove;
	209
1da177e4	210	/* Register sysfs hooks */
f187fc04	211	data->hwmon_dev = hwmon_device_register(dev);
1beeffe4 TJ	212	if (IS_ERR(data->hwmon_dev)) {
1beeffe4 TJ	213	err = PTR_ERR(data->hwmon_dev);
ccc5c306	214	goto exit_remove;
943b0830 MH	215	}
943b0830 MH	216
1da177e4 LT	217	return 0;
1da177e4 LT	218
ccc5c306	219	exit_remove:
f187fc04 GR	220	device_remove_file(dev, &sensor_dev_attr_temp1_input.dev_attr);
f187fc04 GR	221	device_remove_file(dev, &sensor_dev_attr_temp1_max.dev_attr);
1da177e4 LT	222	return err;
	223	}
	224
dc18a418	225	static int w83l785ts_remove(struct i2c_client *client)
1da177e4	226	{
943b0830	227	struct w83l785ts_data *data = i2c_get_clientdata(client);
1da177e4	228
1beeffe4	229	hwmon_device_unregister(data->hwmon_dev);
ccc5c306 RM	230	device_remove_file(&client->dev,
	231	&sensor_dev_attr_temp1_input.dev_attr);
	232	device_remove_file(&client->dev,
	233	&sensor_dev_attr_temp1_max.dev_attr);
1da177e4	234
1da177e4 LT	235	return 0;
	236	}
	237
	238	static u8 w83l785ts_read_value(struct i2c_client *client, u8 reg, u8 defval)
	239	{
	240	int value, i;
dc18a418 JD	241	struct device *dev;
	242	const char *prefix;
	243
130067d7 GR	244	/*
	245	* We might be called during detection, at which point the client
	246	* isn't yet fully initialized, so we can't use dev_dbg on it
	247	*/
dc18a418 JD	248	if (i2c_get_clientdata(client)) {
	249	dev = &client->dev;
	250	prefix = "";
	251	} else {
	252	dev = &client->adapter->dev;
	253	prefix = "w83l785ts: ";
	254	}
1da177e4	255
130067d7 GR	256	/*
130067d7 GR	257	* Frequent read errors have been reported on Asus boards, so we
1da177e4	258	* retry on read errors. If it still fails (unlikely), return the
130067d7 GR	259	* default value requested by the caller.
130067d7 GR	260	*/
1da177e4 LT	261	for (i = 1; i <= MAX_RETRIES; i++) {
	262	value = i2c_smbus_read_byte_data(client, reg);
	263	if (value >= 0) {
dc18a418 JD	264	dev_dbg(dev, "%sRead 0x%02x from register 0x%02x.\n",
dc18a418 JD	265	prefix, value, reg);
1da177e4 LT	266	return value;
1da177e4 LT	267	}
dc18a418	268	dev_dbg(dev, "%sRead failed, will retry in %d.\n", prefix, i);
1da177e4 LT	269	msleep(i);
	270	}
	271
dc18a418	272	dev_err(dev, "%sCouldn't read value from register 0x%02x.\n", prefix,
4040c415	273	reg);
1da177e4 LT	274	return defval;
	275	}
	276
	277	static struct w83l785ts_data w83l785ts_update_device(struct device dev)
	278	{
	279	struct i2c_client *client = to_i2c_client(dev);
	280	struct w83l785ts_data *data = i2c_get_clientdata(client);
	281
9a61bf63	282	mutex_lock(&data->update_lock);
1da177e4 LT	283
	284	if (!data->valid \|\| time_after(jiffies, data->last_updated + HZ * 2)) {
	285	dev_dbg(&client->dev, "Updating w83l785ts data.\n");
709439a2 JD	286	data->temp[0] = w83l785ts_read_value(client,
	287	W83L785TS_REG_TEMP, data->temp[0]);
	288	data->temp[1] = w83l785ts_read_value(client,
	289	W83L785TS_REG_TEMP_OVER, data->temp[1]);
1da177e4 LT	290
	291	data->last_updated = jiffies;
	292	data->valid = 1;
	293	}
	294
9a61bf63	295	mutex_unlock(&data->update_lock);
1da177e4 LT	296
	297	return data;
	298	}
	299
f0967eea	300	module_i2c_driver(w83l785ts_driver);
1da177e4	301
7c81c60f	302	MODULE_AUTHOR("Jean Delvare <[email protected]>");
1da177e4 LT	303	MODULE_DESCRIPTION("W83L785TS-S driver");
1da177e4 LT	304	MODULE_LICENSE("GPL");