[mirror_ubuntu-bionic-kernel.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 int value;
	struct i2c_client *client = to_i2c_client(dev);
	struct pcf8591_data *data = i2c_get_clientdata(client);
	if ((value = (simple_strtoul(buf, NULL, 10) + 5) / 10) <= 255) {
		data->aout = value;
		i2c_smbus_write_byte_data(client, data->control, data->aout);
		return count;
	}
	return -EINVAL;
}

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 = simple_strtoul(buf, NULL, 10);

	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;

	if (!(data = kzalloc(sizeof(struct pcf8591_data), GFP_KERNEL))) {
		err = -ENOMEM;
		goto exit;
	}

	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)
		goto exit_kfree;

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

	/* Register input3 only in "four single ended inputs" mode */
	if (input_mode == 0) {
		if ((err = device_create_file(&client->dev,
					      &dev_attr_in3_input)))
			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);
exit_kfree:
	kfree(data);
exit:
	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);
	kfree(i2c_get_clientdata(client));
	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	/*
1da177e4	2	Copyright (C) 2001-2004 Aurelien Jarno <aurelien@aurel32.net>
fb4504fe	3	Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
1da177e4 LT	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	*/
	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
	42	/* The PCF8591 control byte
fb4504fe	43	7 6 5 4 3 2 1 0
1da177e4 LT	44	\| 0 \|AOEF\| AIP \| 0 \|AINC\| AICH \| */
	45
	46	/* Analog Output Enable Flag (analog output active if 1) */
	47	#define PCF8591_CONTROL_AOEF 0x40
fb4504fe JD	48
fb4504fe JD	49	/* Analog Input Programming
1da177e4 LT	50	0x00 = four single ended inputs
	51	0x10 = three differential inputs
	52	0x20 = single ended and differential mixed
	53	0x30 = two differential inputs */
	54	#define PCF8591_CONTROL_AIP_MASK 0x30
	55
	56	/* Autoincrement Flag (switch on if 1) */
	57	#define PCF8591_CONTROL_AINC 0x04
	58
	59	/* Channel selection
fb4504fe	60	0x00 = channel 0
1da177e4 LT	61	0x01 = channel 1
	62	0x02 = channel 2
	63	0x03 = channel 3 */
	64	#define PCF8591_CONTROL_AICH_MASK 0x03
	65
	66	/* Initial values */
	67	#define PCF8591_INIT_CONTROL ((input_mode << 4) \| PCF8591_CONTROL_AOEF)
	68	#define PCF8591_INIT_AOUT 0 /* DAC out = 0 */
	69
	70	/* Conversions */
	71	#define REG_TO_SIGNED(reg) (((reg) & 0x80)?((reg) - 256):(reg))
	72
	73	struct pcf8591_data {
4275fcd6	74	struct device *hwmon_dev;
5c085d36	75	struct mutex update_lock;
1da177e4 LT	76
	77	u8 control;
	78	u8 aout;
	79	};
	80
1da177e4 LT	81	static void pcf8591_init_client(struct i2c_client *client);
	82	static int pcf8591_read_channel(struct device *dev, int channel);
	83
1da177e4 LT	84	/* following are the sysfs callback functions */
1da177e4 LT	85	#define show_in_channel(channel) \
a5099cfc	86	static ssize_t show_in##channel##_input(struct device dev, struct device_attribute attr, char *buf) \
1da177e4 LT	87	{ \
	88	return sprintf(buf, "%d\n", pcf8591_read_channel(dev, channel));\
	89	} \
	90	static DEVICE_ATTR(in##channel##_input, S_IRUGO, \
	91	show_in##channel##_input, NULL);
	92
	93	show_in_channel(0);
	94	show_in_channel(1);
	95	show_in_channel(2);
	96	show_in_channel(3);
	97
a5099cfc	98	static ssize_t show_out0_ouput(struct device dev, struct device_attribute attr, char *buf)
1da177e4 LT	99	{
	100	struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
	101	return sprintf(buf, "%d\n", data->aout * 10);
	102	}
	103
a5099cfc	104	static ssize_t set_out0_output(struct device dev, struct device_attribute attr, const char *buf, size_t count)
1da177e4 LT	105	{
	106	unsigned int value;
	107	struct i2c_client *client = to_i2c_client(dev);
	108	struct pcf8591_data *data = i2c_get_clientdata(client);
	109	if ((value = (simple_strtoul(buf, NULL, 10) + 5) / 10) <= 255) {
	110	data->aout = value;
	111	i2c_smbus_write_byte_data(client, data->control, data->aout);
	112	return count;
	113	}
	114	return -EINVAL;
	115	}
	116
fb4504fe	117	static DEVICE_ATTR(out0_output, S_IWUSR \| S_IRUGO,
1da177e4 LT	118	show_out0_ouput, set_out0_output);
1da177e4 LT	119
a5099cfc	120	static ssize_t show_out0_enable(struct device dev, struct device_attribute attr, char *buf)
1da177e4 LT	121	{
	122	struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
	123	return sprintf(buf, "%u\n", !(!(data->control & PCF8591_CONTROL_AOEF)));
	124	}
	125
a5099cfc	126	static ssize_t set_out0_enable(struct device dev, struct device_attribute attr, const char *buf, size_t count)
1da177e4 LT	127	{
	128	struct i2c_client *client = to_i2c_client(dev);
	129	struct pcf8591_data *data = i2c_get_clientdata(client);
	130	unsigned long val = simple_strtoul(buf, NULL, 10);
	131
5c085d36	132	mutex_lock(&data->update_lock);
1da177e4 LT	133	if (val)
	134	data->control \|= PCF8591_CONTROL_AOEF;
	135	else
	136	data->control &= ~PCF8591_CONTROL_AOEF;
	137	i2c_smbus_write_byte(client, data->control);
5c085d36	138	mutex_unlock(&data->update_lock);
1da177e4 LT	139	return count;
	140	}
	141
fb4504fe	142	static DEVICE_ATTR(out0_enable, S_IWUSR \| S_IRUGO,
1da177e4 LT	143	show_out0_enable, set_out0_enable);
1da177e4 LT	144
7d9db67f JD	145	static struct attribute *pcf8591_attributes[] = {
	146	&dev_attr_out0_enable.attr,
	147	&dev_attr_out0_output.attr,
	148	&dev_attr_in0_input.attr,
	149	&dev_attr_in1_input.attr,
	150	NULL
	151	};
	152
	153	static const struct attribute_group pcf8591_attr_group = {
	154	.attrs = pcf8591_attributes,
	155	};
	156
	157	static struct attribute *pcf8591_attributes_opt[] = {
	158	&dev_attr_in2_input.attr,
	159	&dev_attr_in3_input.attr,
	160	NULL
	161	};
	162
	163	static const struct attribute_group pcf8591_attr_group_opt = {
	164	.attrs = pcf8591_attributes_opt,
	165	};
	166
1da177e4 LT	167	/*
	168	* Real code
	169	*/
1da177e4	170
8b77e6ac JD	171	static int pcf8591_probe(struct i2c_client *client,
	172	const struct i2c_device_id *id)
	173	{
	174	struct pcf8591_data *data;
	175	int err;
1da177e4	176
5263ebb5	177	if (!(data = kzalloc(sizeof(struct pcf8591_data), GFP_KERNEL))) {
1da177e4 LT	178	err = -ENOMEM;
	179	goto exit;
	180	}
fb4504fe	181
f741f673	182	i2c_set_clientdata(client, data);
5c085d36	183	mutex_init(&data->update_lock);
1da177e4	184
1da177e4	185	/* Initialize the PCF8591 chip */
f741f673	186	pcf8591_init_client(client);
1da177e4 LT	187
1da177e4 LT	188	/* Register sysfs hooks */
f741f673	189	err = sysfs_create_group(&client->dev.kobj, &pcf8591_attr_group);
7d9db67f	190	if (err)
8b77e6ac	191	goto exit_kfree;
1da177e4 LT	192
1da177e4 LT	193	/* Register input2 if not in "two differential inputs" mode */
7d9db67f	194	if (input_mode != 3) {
f741f673	195	if ((err = device_create_file(&client->dev,
7d9db67f JD	196	&dev_attr_in2_input)))
	197	goto exit_sysfs_remove;
	198	}
	199
1da177e4	200	/* Register input3 only in "four single ended inputs" mode */
7d9db67f	201	if (input_mode == 0) {
f741f673	202	if ((err = device_create_file(&client->dev,
7d9db67f JD	203	&dev_attr_in3_input)))
	204	goto exit_sysfs_remove;
	205	}
	206
4275fcd6 JD	207	data->hwmon_dev = hwmon_device_register(&client->dev);
	208	if (IS_ERR(data->hwmon_dev)) {
	209	err = PTR_ERR(data->hwmon_dev);
	210	goto exit_sysfs_remove;
	211	}
	212
1da177e4	213	return 0;
1da177e4	214
7d9db67f	215	exit_sysfs_remove:
f741f673 JD	216	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
f741f673 JD	217	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
1da177e4 LT	218	exit_kfree:
	219	kfree(data);
	220	exit:
	221	return err;
	222	}
	223
8b77e6ac	224	static int pcf8591_remove(struct i2c_client *client)
1da177e4	225	{
4275fcd6 JD	226	struct pcf8591_data *data = i2c_get_clientdata(client);
	227
	228	hwmon_device_unregister(data->hwmon_dev);
7d9db67f JD	229	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
7d9db67f JD	230	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
1da177e4 LT	231	kfree(i2c_get_clientdata(client));
	232	return 0;
	233	}
	234
	235	/* Called when we have found a new PCF8591. */
	236	static void pcf8591_init_client(struct i2c_client *client)
	237	{
	238	struct pcf8591_data *data = i2c_get_clientdata(client);
	239	data->control = PCF8591_INIT_CONTROL;
	240	data->aout = PCF8591_INIT_AOUT;
	241
	242	i2c_smbus_write_byte_data(client, data->control, data->aout);
fb4504fe JD	243
fb4504fe JD	244	/* The first byte transmitted contains the conversion code of the
1da177e4 LT	245	previous read cycle. FLUSH IT! */
	246	i2c_smbus_read_byte(client);
	247	}
	248
	249	static int pcf8591_read_channel(struct device *dev, int channel)
	250	{
	251	u8 value;
	252	struct i2c_client *client = to_i2c_client(dev);
	253	struct pcf8591_data *data = i2c_get_clientdata(client);
	254
5c085d36	255	mutex_lock(&data->update_lock);
1da177e4 LT	256
	257	if ((data->control & PCF8591_CONTROL_AICH_MASK) != channel) {
	258	data->control = (data->control & ~PCF8591_CONTROL_AICH_MASK)
	259	\| channel;
	260	i2c_smbus_write_byte(client, data->control);
fb4504fe JD	261
fb4504fe JD	262	/* The first byte transmitted contains the conversion code of
1da177e4 LT	263	the previous read cycle. FLUSH IT! */
	264	i2c_smbus_read_byte(client);
	265	}
	266	value = i2c_smbus_read_byte(client);
	267
5c085d36	268	mutex_unlock(&data->update_lock);
1da177e4 LT	269
	270	if ((channel == 2 && input_mode == 2) \|\|
	271	(channel != 3 && (input_mode == 1 \|\| input_mode == 3)))
	272	return (10 * REG_TO_SIGNED(value));
	273	else
	274	return (10 * value);
	275	}
	276
8b77e6ac JD	277	static const struct i2c_device_id pcf8591_id[] = {
	278	{ "pcf8591", 0 },
	279	{ }
	280	};
	281	MODULE_DEVICE_TABLE(i2c, pcf8591_id);
	282
	283	static struct i2c_driver pcf8591_driver = {
	284	.driver = {
	285	.name = "pcf8591",
	286	},
	287	.probe = pcf8591_probe,
	288	.remove = pcf8591_remove,
	289	.id_table = pcf8591_id,
8b77e6ac JD	290	};
8b77e6ac JD	291
1da177e4 LT	292	static int __init pcf8591_init(void)
	293	{
	294	if (input_mode < 0 \|\| input_mode > 3) {
2caec134	295	pr_warn("invalid input_mode (%d)\n", input_mode);
1da177e4 LT	296	input_mode = 0;
	297	}
	298	return i2c_add_driver(&pcf8591_driver);
	299	}
	300
	301	static void __exit pcf8591_exit(void)
	302	{
	303	i2c_del_driver(&pcf8591_driver);
	304	}
	305
	306	MODULE_AUTHOR("Aurelien Jarno <aurelien@aurel32.net>");
	307	MODULE_DESCRIPTION("PCF8591 driver");
	308	MODULE_LICENSE("GPL");
	309
	310	module_init(pcf8591_init);
	311	module_exit(pcf8591_exit);