[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / hwmon / ds620.c

/*
 *  ds620.c - Support for temperature sensor and thermostat DS620
 *
 *  Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de>
 *
 *  based on ds1621.c by Christian W. Zuckschwerdt  <zany@triq.net>
 *
 *  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.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
#include <linux/i2c/ds620.h>

/*
 * Many DS620 constants specified below
 *  15   14   13   12   11   10   09    08
 * |Done|NVB |THF |TLF |R1  |R0  |AUTOC|1SHOT|
 *
 *  07   06   05   04   03   02   01    00
 * |PO2 |PO1 |A2  |A1  |A0  |    |     |     |
 */
#define DS620_REG_CONFIG_DONE		0x8000
#define DS620_REG_CONFIG_NVB		0x4000
#define DS620_REG_CONFIG_THF		0x2000
#define DS620_REG_CONFIG_TLF		0x1000
#define DS620_REG_CONFIG_R1		0x0800
#define DS620_REG_CONFIG_R0		0x0400
#define DS620_REG_CONFIG_AUTOC		0x0200
#define DS620_REG_CONFIG_1SHOT		0x0100
#define DS620_REG_CONFIG_PO2		0x0080
#define DS620_REG_CONFIG_PO1		0x0040
#define DS620_REG_CONFIG_A2		0x0020
#define DS620_REG_CONFIG_A1		0x0010
#define DS620_REG_CONFIG_A0		0x0008

/* The DS620 registers */
static const u8 DS620_REG_TEMP[3] = {
	0xAA,			/* input, word, RO */
	0xA2,			/* min, word, RW */
	0xA0,			/* max, word, RW */
};

#define DS620_REG_CONF		0xAC	/* word, RW */
#define DS620_COM_START		0x51	/* no data */
#define DS620_COM_STOP		0x22	/* no data */

/* Each client has this additional data */
struct ds620_data {
	struct device *hwmon_dev;
	struct mutex update_lock;
	char valid;		/* !=0 if following fields are valid */
	unsigned long last_updated;	/* In jiffies */

	s16 temp[3];		/* Register values, word */
};

static void ds620_init_client(struct i2c_client *client)
{
	struct ds620_platform_data *ds620_info = client->dev.platform_data;
	u16 conf, new_conf;

	new_conf = conf =
	    i2c_smbus_read_word_swapped(client, DS620_REG_CONF);

	/* switch to continuous conversion mode */
	new_conf &= ~DS620_REG_CONFIG_1SHOT;
	/* already high at power-on, but don't trust the BIOS! */
	new_conf |= DS620_REG_CONFIG_PO2;
	/* thermostat mode according to platform data */
	if (ds620_info && ds620_info->pomode == 1)
		new_conf &= ~DS620_REG_CONFIG_PO1; /* PO_LOW */
	else if (ds620_info && ds620_info->pomode == 2)
		new_conf |= DS620_REG_CONFIG_PO1; /* PO_HIGH */
	else
		new_conf &= ~DS620_REG_CONFIG_PO2; /* always low */
	/* with highest precision */
	new_conf |= DS620_REG_CONFIG_R1 | DS620_REG_CONFIG_R0;

	if (conf != new_conf)
		i2c_smbus_write_word_swapped(client, DS620_REG_CONF, new_conf);

	/* start conversion */
	i2c_smbus_write_byte(client, DS620_COM_START);
}

static struct ds620_data *ds620_update_client(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct ds620_data *data = i2c_get_clientdata(client);
	struct ds620_data *ret = data;

	mutex_lock(&data->update_lock);

	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
	    || !data->valid) {
		int i;
		int res;

		dev_dbg(&client->dev, "Starting ds620 update\n");

		for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
			res = i2c_smbus_read_word_swapped(client,
							  DS620_REG_TEMP[i]);
			if (res < 0) {
				ret = ERR_PTR(res);
				goto abort;
			}

			data->temp[i] = res;
		}

		data->last_updated = jiffies;
		data->valid = 1;
	}
abort:
	mutex_unlock(&data->update_lock);

	return ret;
}

static ssize_t show_temp(struct device *dev, struct device_attribute *da,
			 char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	struct ds620_data *data = ds620_update_client(dev);

	if (IS_ERR(data))
		return PTR_ERR(data);

	return sprintf(buf, "%d\n", ((data->temp[attr->index] / 8) * 625) / 10);
}

static ssize_t set_temp(struct device *dev, struct device_attribute *da,
			const char *buf, size_t count)
{
	int res;
	long val;

	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	struct i2c_client *client = to_i2c_client(dev);
	struct ds620_data *data = i2c_get_clientdata(client);

	res = kstrtol(buf, 10, &val);

	if (res)
		return res;

	val = (val * 10 / 625) * 8;

	mutex_lock(&data->update_lock);
	data->temp[attr->index] = val;
	i2c_smbus_write_word_swapped(client, DS620_REG_TEMP[attr->index],
				     data->temp[attr->index]);
	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t show_alarm(struct device *dev, struct device_attribute *da,
			  char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	struct ds620_data *data = ds620_update_client(dev);
	struct i2c_client *client = to_i2c_client(dev);
	u16 conf, new_conf;
	int res;

	if (IS_ERR(data))
		return PTR_ERR(data);

	/* reset alarms if necessary */
	res = i2c_smbus_read_word_swapped(client, DS620_REG_CONF);
	if (res < 0)
		return res;

	new_conf = conf = res;
	new_conf &= ~attr->index;
	if (conf != new_conf) {
		res = i2c_smbus_write_word_swapped(client, DS620_REG_CONF,
						   new_conf);
		if (res < 0)
			return res;
	}

	return sprintf(buf, "%d\n", !!(conf & attr->index));
}

static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp, set_temp, 1);
static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, set_temp, 2);
static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
			  DS620_REG_CONFIG_TLF);
static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
			  DS620_REG_CONFIG_THF);

static struct attribute *ds620_attributes[] = {
	&sensor_dev_attr_temp1_input.dev_attr.attr,
	&sensor_dev_attr_temp1_min.dev_attr.attr,
	&sensor_dev_attr_temp1_max.dev_attr.attr,
	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
	NULL
};

static const struct attribute_group ds620_group = {
	.attrs = ds620_attributes,
};

static int ds620_probe(struct i2c_client *client,
		       const struct i2c_device_id *id)
{
	struct ds620_data *data;
	int err;

	data = devm_kzalloc(&client->dev, sizeof(struct ds620_data),
			    GFP_KERNEL);
	if (!data)
		return -ENOMEM;

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

	/* Initialize the DS620 chip */
	ds620_init_client(client);

	/* Register sysfs hooks */
	err = sysfs_create_group(&client->dev.kobj, &ds620_group);
	if (err)
		return err;

	data->hwmon_dev = hwmon_device_register(&client->dev);
	if (IS_ERR(data->hwmon_dev)) {
		err = PTR_ERR(data->hwmon_dev);
		goto exit_remove_files;
	}

	dev_info(&client->dev, "temperature sensor found\n");

	return 0;

exit_remove_files:
	sysfs_remove_group(&client->dev.kobj, &ds620_group);
	return err;
}

static int ds620_remove(struct i2c_client *client)
{
	struct ds620_data *data = i2c_get_clientdata(client);

	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&client->dev.kobj, &ds620_group);

	return 0;
}

static const struct i2c_device_id ds620_id[] = {
	{"ds620", 0},
	{}
};

MODULE_DEVICE_TABLE(i2c, ds620_id);

/* This is the driver that will be inserted */
static struct i2c_driver ds620_driver = {
	.class = I2C_CLASS_HWMON,
	.driver = {
		   .name = "ds620",
	},
	.probe = ds620_probe,
	.remove = ds620_remove,
	.id_table = ds620_id,
};

module_i2c_driver(ds620_driver);

MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
MODULE_DESCRIPTION("DS620 driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
60994698 RS	1	/*
	2	* ds620.c - Support for temperature sensor and thermostat DS620
	3	*
	4	* Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de>
	5	*
	6	* based on ds1621.c by Christian W. Zuckschwerdt <zany@triq.net>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software
	20	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	21	*/
	22
	23	#include <linux/module.h>
	24	#include <linux/init.h>
	25	#include <linux/slab.h>
	26	#include <linux/jiffies.h>
	27	#include <linux/i2c.h>
	28	#include <linux/hwmon.h>
	29	#include <linux/hwmon-sysfs.h>
	30	#include <linux/err.h>
	31	#include <linux/mutex.h>
	32	#include <linux/sysfs.h>
	33	#include <linux/i2c/ds620.h>
	34
	35	/*
	36	* Many DS620 constants specified below
	37	* 15 14 13 12 11 10 09 08
	38	* \|Done\|NVB \|THF \|TLF \|R1 \|R0 \|AUTOC\|1SHOT\|
	39	*
	40	* 07 06 05 04 03 02 01 00
	41	* \|PO2 \|PO1 \|A2 \|A1 \|A0 \| \| \| \|
	42	*/
	43	#define DS620_REG_CONFIG_DONE 0x8000
	44	#define DS620_REG_CONFIG_NVB 0x4000
	45	#define DS620_REG_CONFIG_THF 0x2000
	46	#define DS620_REG_CONFIG_TLF 0x1000
	47	#define DS620_REG_CONFIG_R1 0x0800
	48	#define DS620_REG_CONFIG_R0 0x0400
	49	#define DS620_REG_CONFIG_AUTOC 0x0200
	50	#define DS620_REG_CONFIG_1SHOT 0x0100
	51	#define DS620_REG_CONFIG_PO2 0x0080
	52	#define DS620_REG_CONFIG_PO1 0x0040
	53	#define DS620_REG_CONFIG_A2 0x0020
	54	#define DS620_REG_CONFIG_A1 0x0010
	55	#define DS620_REG_CONFIG_A0 0x0008
	56
	57	/* The DS620 registers */
	58	static const u8 DS620_REG_TEMP[3] = {
	59	0xAA, /* input, word, RO */
	60	0xA2, /* min, word, RW */
	61	0xA0, /* max, word, RW */
	62	};
	63
	64	#define DS620_REG_CONF 0xAC /* word, RW */
65	#define DS620_COM_START 0x51 /* no data */
66	#define DS620_COM_STOP 0x22 /* no data */
67
68	/* Each client has this additional data */
69	struct ds620_data {
70	struct device *hwmon_dev;
71	struct mutex update_lock;
72	char valid; /* !=0 if following fields are valid */
73	unsigned long last_updated; /* In jiffies */
74
cc41d586	75	s16 temp[3]; /* Register values, word */
60994698 RS	76	};
60994698 RS	77
60994698 RS	78	static void ds620_init_client(struct i2c_client *client)
	79	{
	80	struct ds620_platform_data *ds620_info = client->dev.platform_data;
	81	u16 conf, new_conf;
	82
	83	new_conf = conf =
90f4102c	84	i2c_smbus_read_word_swapped(client, DS620_REG_CONF);
60994698 RS	85
	86	/* switch to continuous conversion mode */
	87	new_conf &= ~DS620_REG_CONFIG_1SHOT;
	88	/* already high at power-on, but don't trust the BIOS! */
	89	new_conf \|= DS620_REG_CONFIG_PO2;
	90	/* thermostat mode according to platform data */
	91	if (ds620_info && ds620_info->pomode == 1)
	92	new_conf &= ~DS620_REG_CONFIG_PO1; /* PO_LOW */
	93	else if (ds620_info && ds620_info->pomode == 2)
	94	new_conf \|= DS620_REG_CONFIG_PO1; /* PO_HIGH */
	95	else
	96	new_conf &= ~DS620_REG_CONFIG_PO2; /* always low */
	97	/* with highest precision */
	98	new_conf \|= DS620_REG_CONFIG_R1 \| DS620_REG_CONFIG_R0;
	99
	100	if (conf != new_conf)
90f4102c	101	i2c_smbus_write_word_swapped(client, DS620_REG_CONF, new_conf);
60994698 RS	102
	103	/* start conversion */
	104	i2c_smbus_write_byte(client, DS620_COM_START);
	105	}
	106
	107	static struct ds620_data ds620_update_client(struct device dev)
	108	{
	109	struct i2c_client *client = to_i2c_client(dev);
	110	struct ds620_data *data = i2c_get_clientdata(client);
	111	struct ds620_data *ret = data;
	112
	113	mutex_lock(&data->update_lock);
	114
	115	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
	116	\|\| !data->valid) {
	117	int i;
	118	int res;
	119
	120	dev_dbg(&client->dev, "Starting ds620 update\n");
	121
	122	for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
90f4102c JD	123	res = i2c_smbus_read_word_swapped(client,
90f4102c JD	124	DS620_REG_TEMP[i]);
60994698 RS	125	if (res < 0) {
	126	ret = ERR_PTR(res);
	127	goto abort;
	128	}
	129
	130	data->temp[i] = res;
	131	}
	132
	133	data->last_updated = jiffies;
	134	data->valid = 1;
	135	}
	136	abort:
	137	mutex_unlock(&data->update_lock);
	138
	139	return ret;
	140	}
	141
	142	static ssize_t show_temp(struct device dev, struct device_attribute da,
	143	char *buf)
	144	{
	145	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	146	struct ds620_data *data = ds620_update_client(dev);
	147
	148	if (IS_ERR(data))
	149	return PTR_ERR(data);
	150
	151	return sprintf(buf, "%d\n", ((data->temp[attr->index] / 8) * 625) / 10);
	152	}
	153
	154	static ssize_t set_temp(struct device dev, struct device_attribute da,
	155	const char *buf, size_t count)
	156	{
	157	int res;
	158	long val;
	159
	160	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	161	struct i2c_client *client = to_i2c_client(dev);
	162	struct ds620_data *data = i2c_get_clientdata(client);
	163
179c4fdb	164	res = kstrtol(buf, 10, &val);
60994698 RS	165
	166	if (res)
	167	return res;
	168
	169	val = (val * 10 / 625) * 8;
	170
	171	mutex_lock(&data->update_lock);
	172	data->temp[attr->index] = val;
90f4102c JD	173	i2c_smbus_write_word_swapped(client, DS620_REG_TEMP[attr->index],
90f4102c JD	174	data->temp[attr->index]);
60994698 RS	175	mutex_unlock(&data->update_lock);
	176	return count;
	177	}
	178
	179	static ssize_t show_alarm(struct device dev, struct device_attribute da,
	180	char *buf)
	181	{
	182	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	183	struct ds620_data *data = ds620_update_client(dev);
	184	struct i2c_client *client = to_i2c_client(dev);
	185	u16 conf, new_conf;
	186	int res;
	187
	188	if (IS_ERR(data))
	189	return PTR_ERR(data);
	190
	191	/* reset alarms if necessary */
90f4102c	192	res = i2c_smbus_read_word_swapped(client, DS620_REG_CONF);
60994698 RS	193	if (res < 0)
	194	return res;
	195
90f4102c	196	new_conf = conf = res;
60994698 RS	197	new_conf &= ~attr->index;
60994698 RS	198	if (conf != new_conf) {
90f4102c JD	199	res = i2c_smbus_write_word_swapped(client, DS620_REG_CONF,
90f4102c JD	200	new_conf);
60994698 RS	201	if (res < 0)
	202	return res;
	203	}
	204
	205	return sprintf(buf, "%d\n", !!(conf & attr->index));
	206	}
	207
	208	static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
	209	static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR \| S_IRUGO, show_temp, set_temp, 1);
	210	static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR \| S_IRUGO, show_temp, set_temp, 2);
	211	static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
	212	DS620_REG_CONFIG_TLF);
	213	static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
	214	DS620_REG_CONFIG_THF);
	215
	216	static struct attribute *ds620_attributes[] = {
	217	&sensor_dev_attr_temp1_input.dev_attr.attr,
	218	&sensor_dev_attr_temp1_min.dev_attr.attr,
	219	&sensor_dev_attr_temp1_max.dev_attr.attr,
	220	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
	221	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
	222	NULL
	223	};
	224
	225	static const struct attribute_group ds620_group = {
	226	.attrs = ds620_attributes,
	227	};
	228
	229	static int ds620_probe(struct i2c_client *client,
	230	const struct i2c_device_id *id)
	231	{
	232	struct ds620_data *data;
	233	int err;
	234
3aa9d1df GR	235	data = devm_kzalloc(&client->dev, sizeof(struct ds620_data),
	236	GFP_KERNEL);
	237	if (!data)
	238	return -ENOMEM;
60994698 RS	239
	240	i2c_set_clientdata(client, data);
	241	mutex_init(&data->update_lock);
	242
	243	/* Initialize the DS620 chip */
	244	ds620_init_client(client);
	245
	246	/* Register sysfs hooks */
	247	err = sysfs_create_group(&client->dev.kobj, &ds620_group);
	248	if (err)
3aa9d1df	249	return err;
60994698 RS	250
	251	data->hwmon_dev = hwmon_device_register(&client->dev);
	252	if (IS_ERR(data->hwmon_dev)) {
	253	err = PTR_ERR(data->hwmon_dev);
	254	goto exit_remove_files;
	255	}
	256
	257	dev_info(&client->dev, "temperature sensor found\n");
	258
	259	return 0;
	260
	261	exit_remove_files:
	262	sysfs_remove_group(&client->dev.kobj, &ds620_group);
60994698 RS	263	return err;
	264	}
	265
	266	static int ds620_remove(struct i2c_client *client)
	267	{
	268	struct ds620_data *data = i2c_get_clientdata(client);
	269
	270	hwmon_device_unregister(data->hwmon_dev);
	271	sysfs_remove_group(&client->dev.kobj, &ds620_group);
	272
60994698 RS	273	return 0;
	274	}
	275
	276	static const struct i2c_device_id ds620_id[] = {
	277	{"ds620", 0},
	278	{}
	279	};
	280
	281	MODULE_DEVICE_TABLE(i2c, ds620_id);
	282
	283	/* This is the driver that will be inserted */
	284	static struct i2c_driver ds620_driver = {
	285	.class = I2C_CLASS_HWMON,
	286	.driver = {
	287	.name = "ds620",
	288	},
	289	.probe = ds620_probe,
	290	.remove = ds620_remove,
	291	.id_table = ds620_id,
	292	};
	293
f0967eea	294	module_i2c_driver(ds620_driver);
60994698 RS	295
	296	MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
	297	MODULE_DESCRIPTION("DS620 driver");
	298	MODULE_LICENSE("GPL");