[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / hwmon / pcf8591.c

/*
 * Copyright (C) 2001-2004 Aurelien Jarno <aurelien@aurel32.net>
 * Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
 * the help of Jean Delvare <khali@linux-fr.org>
 *
 * 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.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

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

/* Insmod parameters */

static int input_mode;
module_param(input_mode, int, 0);
MODULE_PARM_DESC(input_mode,
	"Analog input mode:\n"
	" 0 = four single ended inputs\n"
	" 1 = three differential inputs\n"
	" 2 = single ended and differential mixed\n"
	" 3 = two differential inputs\n");

/*
 * The PCF8591 control byte
 *      7    6    5    4    3    2    1    0
 *   |  0 |AOEF|   AIP   |  0 |AINC|  AICH   |
 */

/* Analog Output Enable Flag (analog output active if 1) */
#define PCF8591_CONTROL_AOEF		0x40

/*
 * Analog Input Programming
 * 0x00 = four single ended inputs
 * 0x10 = three differential inputs
 * 0x20 = single ended and differential mixed
 * 0x30 = two differential inputs
 */
#define PCF8591_CONTROL_AIP_MASK	0x30

/* Autoincrement Flag (switch on if 1) */
#define PCF8591_CONTROL_AINC		0x04

/*
 * Channel selection
 * 0x00 = channel 0
 * 0x01 = channel 1
 * 0x02 = channel 2
 * 0x03 = channel 3
 */
#define PCF8591_CONTROL_AICH_MASK	0x03

/* Initial values */
#define PCF8591_INIT_CONTROL	((input_mode << 4) | PCF8591_CONTROL_AOEF)
#define PCF8591_INIT_AOUT	0	/* DAC out = 0 */

/* Conversions */
#define REG_TO_SIGNED(reg)	(((reg) & 0x80) ? ((reg) - 256) : (reg))

struct pcf8591_data {
	struct device *hwmon_dev;
	struct mutex update_lock;

	u8 control;
	u8 aout;
};

static void pcf8591_init_client(struct i2c_client *client);
static int pcf8591_read_channel(struct device *dev, int channel);

/* following are the sysfs callback functions */
#define show_in_channel(channel)					\
static ssize_t show_in##channel##_input(struct device *dev,		\
					struct device_attribute *attr,	\
					char *buf)			\
{									\
	return sprintf(buf, "%d\n", pcf8591_read_channel(dev, channel));\
}									\
static DEVICE_ATTR(in##channel##_input, S_IRUGO,			\
		   show_in##channel##_input, NULL);

show_in_channel(0);
show_in_channel(1);
show_in_channel(2);
show_in_channel(3);

static ssize_t show_out0_ouput(struct device *dev,
			       struct device_attribute *attr, char *buf)
{
	struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
	return sprintf(buf, "%d\n", data->aout * 10);
}

static ssize_t set_out0_output(struct device *dev,
			       struct device_attribute *attr,
			       const char *buf, size_t count)
{
	unsigned long val;
	struct i2c_client *client = to_i2c_client(dev);
	struct pcf8591_data *data = i2c_get_clientdata(client);
	int err;

	err = kstrtoul(buf, 10, &val);
	if (err)
		return err;

	val /= 10;
	if (val > 255)
		return -EINVAL;

	data->aout = val;
	i2c_smbus_write_byte_data(client, data->control, data->aout);
	return count;
}

static DEVICE_ATTR(out0_output, S_IWUSR | S_IRUGO,
		   show_out0_ouput, set_out0_output);

static ssize_t show_out0_enable(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
	return sprintf(buf, "%u\n", !(!(data->control & PCF8591_CONTROL_AOEF)));
}

static ssize_t set_out0_enable(struct device *dev,
			       struct device_attribute *attr,
			       const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct pcf8591_data *data = i2c_get_clientdata(client);
	unsigned long val;
	int err;

	err = kstrtoul(buf, 10, &val);
	if (err)
		return err;

	mutex_lock(&data->update_lock);
	if (val)
		data->control |= PCF8591_CONTROL_AOEF;
	else
		data->control &= ~PCF8591_CONTROL_AOEF;
	i2c_smbus_write_byte(client, data->control);
	mutex_unlock(&data->update_lock);
	return count;
}

static DEVICE_ATTR(out0_enable, S_IWUSR | S_IRUGO,
		   show_out0_enable, set_out0_enable);

static struct attribute *pcf8591_attributes[] = {
	&dev_attr_out0_enable.attr,
	&dev_attr_out0_output.attr,
	&dev_attr_in0_input.attr,
	&dev_attr_in1_input.attr,
	NULL
};

static const struct attribute_group pcf8591_attr_group = {
	.attrs = pcf8591_attributes,
};

static struct attribute *pcf8591_attributes_opt[] = {
	&dev_attr_in2_input.attr,
	&dev_attr_in3_input.attr,
	NULL
};

static const struct attribute_group pcf8591_attr_group_opt = {
	.attrs = pcf8591_attributes_opt,
};

/*
 * Real code
 */

static int pcf8591_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct pcf8591_data *data;
	int err;

	data = devm_kzalloc(&client->dev, sizeof(struct pcf8591_data),
			    GFP_KERNEL);
	if (!data)
		return -ENOMEM;

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

	/* Initialize the PCF8591 chip */
	pcf8591_init_client(client);

	/* Register sysfs hooks */
	err = sysfs_create_group(&client->dev.kobj, &pcf8591_attr_group);
	if (err)
		return err;

	/* Register input2 if not in "two differential inputs" mode */
	if (input_mode != 3) {
		err = device_create_file(&client->dev, &dev_attr_in2_input);
		if (err)
			goto exit_sysfs_remove;
	}

	/* Register input3 only in "four single ended inputs" mode */
	if (input_mode == 0) {
		err = device_create_file(&client->dev, &dev_attr_in3_input);
		if (err)
			goto exit_sysfs_remove;
	}

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

	return 0;

exit_sysfs_remove:
	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
	return err;
}

static int pcf8591_remove(struct i2c_client *client)
{
	struct pcf8591_data *data = i2c_get_clientdata(client);

	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
	return 0;
}

/* Called when we have found a new PCF8591. */
static void pcf8591_init_client(struct i2c_client *client)
{
	struct pcf8591_data *data = i2c_get_clientdata(client);
	data->control = PCF8591_INIT_CONTROL;
	data->aout = PCF8591_INIT_AOUT;

	i2c_smbus_write_byte_data(client, data->control, data->aout);

	/*
	 * The first byte transmitted contains the conversion code of the
	 * previous read cycle. FLUSH IT!
	 */
	i2c_smbus_read_byte(client);
}

static int pcf8591_read_channel(struct device *dev, int channel)
{
	u8 value;
	struct i2c_client *client = to_i2c_client(dev);
	struct pcf8591_data *data = i2c_get_clientdata(client);

	mutex_lock(&data->update_lock);

	if ((data->control & PCF8591_CONTROL_AICH_MASK) != channel) {
		data->control = (data->control & ~PCF8591_CONTROL_AICH_MASK)
			      | channel;
		i2c_smbus_write_byte(client, data->control);

		/*
		 * The first byte transmitted contains the conversion code of
		 * the previous read cycle. FLUSH IT!
		 */
		i2c_smbus_read_byte(client);
	}
	value = i2c_smbus_read_byte(client);

	mutex_unlock(&data->update_lock);

	if ((channel == 2 && input_mode == 2) ||
	    (channel != 3 && (input_mode == 1 || input_mode == 3)))
		return 10 * REG_TO_SIGNED(value);
	else
		return 10 * value;
}

static const struct i2c_device_id pcf8591_id[] = {
	{ "pcf8591", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, pcf8591_id);

static struct i2c_driver pcf8591_driver = {
	.driver = {
		.name	= "pcf8591",
	},
	.probe		= pcf8591_probe,
	.remove		= pcf8591_remove,
	.id_table	= pcf8591_id,
};

static int __init pcf8591_init(void)
{
	if (input_mode < 0 || input_mode > 3) {
		pr_warn("invalid input_mode (%d)\n", input_mode);
		input_mode = 0;
	}
	return i2c_add_driver(&pcf8591_driver);
}

static void __exit pcf8591_exit(void)
{
	i2c_del_driver(&pcf8591_driver);
}

MODULE_AUTHOR("Aurelien Jarno <aurelien@aurel32.net>");
MODULE_DESCRIPTION("PCF8591 driver");
MODULE_LICENSE("GPL");

module_init(pcf8591_init);
module_exit(pcf8591_exit);
Commit	Line	Data
1da177e4	1	/*
57256088 GR	2	* Copyright (C) 2001-2004 Aurelien Jarno <aurelien@aurel32.net>
	3	* Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
	4	* the help of Jean Delvare <khali@linux-fr.org>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	19	*/
1da177e4	20
2caec134 JP	21	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
2caec134 JP	22
1da177e4 LT	23	#include <linux/module.h>
	24	#include <linux/init.h>
	25	#include <linux/slab.h>
	26	#include <linux/i2c.h>
5c085d36	27	#include <linux/mutex.h>
4275fcd6 JD	28	#include <linux/err.h>
4275fcd6 JD	29	#include <linux/hwmon.h>
1da177e4	30
1da177e4	31	/* Insmod parameters */
1da177e4 LT	32
	33	static int input_mode;
	34	module_param(input_mode, int, 0);
	35	MODULE_PARM_DESC(input_mode,
	36	"Analog input mode:\n"
	37	" 0 = four single ended inputs\n"
	38	" 1 = three differential inputs\n"
	39	" 2 = single ended and differential mixed\n"
	40	" 3 = two differential inputs\n");
	41
57256088 GR	42	/*
	43	* The PCF8591 control byte
	44	* 7 6 5 4 3 2 1 0
	45	* \| 0 \|AOEF\| AIP \| 0 \|AINC\| AICH \|
	46	*/
1da177e4 LT	47
	48	/* Analog Output Enable Flag (analog output active if 1) */
	49	#define PCF8591_CONTROL_AOEF 0x40
fb4504fe	50
57256088 GR	51	/*
	52	* Analog Input Programming
	53	* 0x00 = four single ended inputs
	54	* 0x10 = three differential inputs
	55	* 0x20 = single ended and differential mixed
	56	* 0x30 = two differential inputs
	57	*/
1da177e4 LT	58	#define PCF8591_CONTROL_AIP_MASK 0x30
	59
	60	/* Autoincrement Flag (switch on if 1) */
	61	#define PCF8591_CONTROL_AINC 0x04
	62
57256088 GR	63	/*
	64	* Channel selection
	65	* 0x00 = channel 0
	66	* 0x01 = channel 1
	67	* 0x02 = channel 2
	68	* 0x03 = channel 3
	69	*/
1da177e4 LT	70	#define PCF8591_CONTROL_AICH_MASK 0x03
	71
	72	/* Initial values */
	73	#define PCF8591_INIT_CONTROL ((input_mode << 4) \| PCF8591_CONTROL_AOEF)
	74	#define PCF8591_INIT_AOUT 0 /* DAC out = 0 */
	75
	76	/* Conversions */
57256088	77	#define REG_TO_SIGNED(reg) (((reg) & 0x80) ? ((reg) - 256) : (reg))
1da177e4 LT	78
1da177e4 LT	79	struct pcf8591_data {
4275fcd6	80	struct device *hwmon_dev;
5c085d36	81	struct mutex update_lock;
1da177e4 LT	82
	83	u8 control;
	84	u8 aout;
	85	};
	86
1da177e4 LT	87	static void pcf8591_init_client(struct i2c_client *client);
	88	static int pcf8591_read_channel(struct device *dev, int channel);
	89
1da177e4 LT	90	/* following are the sysfs callback functions */
1da177e4 LT	91	#define show_in_channel(channel) \
57256088 GR	92	static ssize_t show_in##channel##_input(struct device *dev, \
	93	struct device_attribute *attr, \
	94	char *buf) \
1da177e4 LT	95	{ \
	96	return sprintf(buf, "%d\n", pcf8591_read_channel(dev, channel));\
	97	} \
	98	static DEVICE_ATTR(in##channel##_input, S_IRUGO, \
	99	show_in##channel##_input, NULL);
	100
	101	show_in_channel(0);
	102	show_in_channel(1);
	103	show_in_channel(2);
	104	show_in_channel(3);
	105
57256088 GR	106	static ssize_t show_out0_ouput(struct device *dev,
57256088 GR	107	struct device_attribute attr, char buf)
1da177e4 LT	108	{
	109	struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
	110	return sprintf(buf, "%d\n", data->aout * 10);
	111	}
	112
57256088 GR	113	static ssize_t set_out0_output(struct device *dev,
	114	struct device_attribute *attr,
	115	const char *buf, size_t count)
1da177e4	116	{
57256088	117	unsigned long val;
1da177e4 LT	118	struct i2c_client *client = to_i2c_client(dev);
1da177e4 LT	119	struct pcf8591_data *data = i2c_get_clientdata(client);
57256088 GR	120	int err;
	121
	122	err = kstrtoul(buf, 10, &val);
	123	if (err)
	124	return err;
	125
	126	val /= 10;
	127	if (val > 255)
	128	return -EINVAL;
	129
	130	data->aout = val;
	131	i2c_smbus_write_byte_data(client, data->control, data->aout);
	132	return count;
1da177e4 LT	133	}
1da177e4 LT	134
fb4504fe	135	static DEVICE_ATTR(out0_output, S_IWUSR \| S_IRUGO,
1da177e4 LT	136	show_out0_ouput, set_out0_output);
1da177e4 LT	137
57256088 GR	138	static ssize_t show_out0_enable(struct device *dev,
57256088 GR	139	struct device_attribute attr, char buf)
1da177e4 LT	140	{
	141	struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
	142	return sprintf(buf, "%u\n", !(!(data->control & PCF8591_CONTROL_AOEF)));
	143	}
	144
57256088 GR	145	static ssize_t set_out0_enable(struct device *dev,
	146	struct device_attribute *attr,
	147	const char *buf, size_t count)
1da177e4 LT	148	{
	149	struct i2c_client *client = to_i2c_client(dev);
	150	struct pcf8591_data *data = i2c_get_clientdata(client);
57256088 GR	151	unsigned long val;
	152	int err;
	153
	154	err = kstrtoul(buf, 10, &val);
	155	if (err)
	156	return err;
1da177e4	157
5c085d36	158	mutex_lock(&data->update_lock);
1da177e4 LT	159	if (val)
	160	data->control \|= PCF8591_CONTROL_AOEF;
	161	else
	162	data->control &= ~PCF8591_CONTROL_AOEF;
	163	i2c_smbus_write_byte(client, data->control);
5c085d36	164	mutex_unlock(&data->update_lock);
1da177e4 LT	165	return count;
	166	}
	167
fb4504fe	168	static DEVICE_ATTR(out0_enable, S_IWUSR \| S_IRUGO,
1da177e4 LT	169	show_out0_enable, set_out0_enable);
1da177e4 LT	170
7d9db67f JD	171	static struct attribute *pcf8591_attributes[] = {
	172	&dev_attr_out0_enable.attr,
	173	&dev_attr_out0_output.attr,
	174	&dev_attr_in0_input.attr,
	175	&dev_attr_in1_input.attr,
	176	NULL
	177	};
	178
	179	static const struct attribute_group pcf8591_attr_group = {
	180	.attrs = pcf8591_attributes,
	181	};
	182
	183	static struct attribute *pcf8591_attributes_opt[] = {
	184	&dev_attr_in2_input.attr,
	185	&dev_attr_in3_input.attr,
	186	NULL
	187	};
	188
	189	static const struct attribute_group pcf8591_attr_group_opt = {
	190	.attrs = pcf8591_attributes_opt,
	191	};
	192
1da177e4 LT	193	/*
	194	* Real code
	195	*/
1da177e4	196
8b77e6ac JD	197	static int pcf8591_probe(struct i2c_client *client,
	198	const struct i2c_device_id *id)
	199	{
	200	struct pcf8591_data *data;
	201	int err;
1da177e4	202
60c2b569 GR	203	data = devm_kzalloc(&client->dev, sizeof(struct pcf8591_data),
	204	GFP_KERNEL);
	205	if (!data)
	206	return -ENOMEM;
fb4504fe	207
f741f673	208	i2c_set_clientdata(client, data);
5c085d36	209	mutex_init(&data->update_lock);
1da177e4	210
1da177e4	211	/* Initialize the PCF8591 chip */
f741f673	212	pcf8591_init_client(client);
1da177e4 LT	213
1da177e4 LT	214	/* Register sysfs hooks */
f741f673	215	err = sysfs_create_group(&client->dev.kobj, &pcf8591_attr_group);
7d9db67f	216	if (err)
60c2b569	217	return err;
1da177e4 LT	218
1da177e4 LT	219	/* Register input2 if not in "two differential inputs" mode */
7d9db67f	220	if (input_mode != 3) {
57256088 GR	221	err = device_create_file(&client->dev, &dev_attr_in2_input);
57256088 GR	222	if (err)
7d9db67f JD	223	goto exit_sysfs_remove;
	224	}
	225
1da177e4	226	/* Register input3 only in "four single ended inputs" mode */
7d9db67f	227	if (input_mode == 0) {
57256088 GR	228	err = device_create_file(&client->dev, &dev_attr_in3_input);
57256088 GR	229	if (err)
7d9db67f JD	230	goto exit_sysfs_remove;
	231	}
	232
4275fcd6 JD	233	data->hwmon_dev = hwmon_device_register(&client->dev);
	234	if (IS_ERR(data->hwmon_dev)) {
	235	err = PTR_ERR(data->hwmon_dev);
	236	goto exit_sysfs_remove;
	237	}
	238
1da177e4	239	return 0;
1da177e4	240
7d9db67f	241	exit_sysfs_remove:
f741f673 JD	242	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
f741f673 JD	243	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
1da177e4 LT	244	return err;
	245	}
	246
8b77e6ac	247	static int pcf8591_remove(struct i2c_client *client)
1da177e4	248	{
4275fcd6 JD	249	struct pcf8591_data *data = i2c_get_clientdata(client);
	250
	251	hwmon_device_unregister(data->hwmon_dev);
7d9db67f JD	252	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
7d9db67f JD	253	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
1da177e4 LT	254	return 0;
	255	}
	256
	257	/* Called when we have found a new PCF8591. */
	258	static void pcf8591_init_client(struct i2c_client *client)
	259	{
	260	struct pcf8591_data *data = i2c_get_clientdata(client);
	261	data->control = PCF8591_INIT_CONTROL;
	262	data->aout = PCF8591_INIT_AOUT;
	263
	264	i2c_smbus_write_byte_data(client, data->control, data->aout);
fb4504fe	265
57256088 GR	266	/*
	267	* The first byte transmitted contains the conversion code of the
	268	* previous read cycle. FLUSH IT!
	269	*/
1da177e4 LT	270	i2c_smbus_read_byte(client);
	271	}
	272
	273	static int pcf8591_read_channel(struct device *dev, int channel)
	274	{
	275	u8 value;
	276	struct i2c_client *client = to_i2c_client(dev);
	277	struct pcf8591_data *data = i2c_get_clientdata(client);
	278
5c085d36	279	mutex_lock(&data->update_lock);
1da177e4 LT	280
	281	if ((data->control & PCF8591_CONTROL_AICH_MASK) != channel) {
	282	data->control = (data->control & ~PCF8591_CONTROL_AICH_MASK)
	283	\| channel;
	284	i2c_smbus_write_byte(client, data->control);
fb4504fe	285
57256088 GR	286	/*
	287	* The first byte transmitted contains the conversion code of
	288	* the previous read cycle. FLUSH IT!
	289	*/
1da177e4 LT	290	i2c_smbus_read_byte(client);
	291	}
	292	value = i2c_smbus_read_byte(client);
	293
5c085d36	294	mutex_unlock(&data->update_lock);
1da177e4 LT	295
	296	if ((channel == 2 && input_mode == 2) \|\|
	297	(channel != 3 && (input_mode == 1 \|\| input_mode == 3)))
7fe83ad8	298	return 10 * REG_TO_SIGNED(value);
1da177e4	299	else
7fe83ad8	300	return 10 * value;
1da177e4 LT	301	}
1da177e4 LT	302
8b77e6ac JD	303	static const struct i2c_device_id pcf8591_id[] = {
	304	{ "pcf8591", 0 },
	305	{ }
	306	};
	307	MODULE_DEVICE_TABLE(i2c, pcf8591_id);
	308
	309	static struct i2c_driver pcf8591_driver = {
	310	.driver = {
	311	.name = "pcf8591",
	312	},
	313	.probe = pcf8591_probe,
	314	.remove = pcf8591_remove,
	315	.id_table = pcf8591_id,
8b77e6ac JD	316	};
8b77e6ac JD	317
1da177e4 LT	318	static int __init pcf8591_init(void)
	319	{
	320	if (input_mode < 0 \|\| input_mode > 3) {
2caec134	321	pr_warn("invalid input_mode (%d)\n", input_mode);
1da177e4 LT	322	input_mode = 0;
	323	}
	324	return i2c_add_driver(&pcf8591_driver);
	325	}
	326
	327	static void __exit pcf8591_exit(void)
	328	{
	329	i2c_del_driver(&pcf8591_driver);
	330	}
	331
	332	MODULE_AUTHOR("Aurelien Jarno <aurelien@aurel32.net>");
	333	MODULE_DESCRIPTION("PCF8591 driver");
	334	MODULE_LICENSE("GPL");
	335
	336	module_init(pcf8591_init);
	337	module_exit(pcf8591_exit);