[linux.git] / drivers / hwmon / pcf8591.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2001-2004 Aurelien Jarno <[email protected]>
 * Ported to Linux 2.6 by Aurelien Jarno <[email protected]> with
 * the help of Jean Delvare <[email protected]>
 */

#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 out0_output_show(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 out0_output_store(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_RW(out0_output);

static ssize_t out0_enable_show(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 out0_enable_store(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_RW(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)
{
	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 void 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);
}

/* 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_new	= 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 <[email protected]>");
MODULE_DESCRIPTION("PCF8591 driver");
MODULE_LICENSE("GPL");

module_init(pcf8591_init);
module_exit(pcf8591_exit);
Commit	Line	Data
74ba9207	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4	2	/*
57256088 GR	3	* Copyright (C) 2001-2004 Aurelien Jarno <[email protected]>
57256088 GR	4	* Ported to Linux 2.6 by Aurelien Jarno <[email protected]> with
7c81c60f	5	* the help of Jean Delvare <[email protected]>
57256088	6	*/
1da177e4	7
2caec134 JP	8	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
2caec134 JP	9
1da177e4 LT	10	#include <linux/module.h>
	11	#include <linux/init.h>
	12	#include <linux/slab.h>
	13	#include <linux/i2c.h>
5c085d36	14	#include <linux/mutex.h>
4275fcd6 JD	15	#include <linux/err.h>
4275fcd6 JD	16	#include <linux/hwmon.h>
1da177e4	17
1da177e4	18	/* Insmod parameters */
1da177e4 LT	19
	20	static int input_mode;
	21	module_param(input_mode, int, 0);
	22	MODULE_PARM_DESC(input_mode,
	23	"Analog input mode:\n"
	24	" 0 = four single ended inputs\n"
	25	" 1 = three differential inputs\n"
	26	" 2 = single ended and differential mixed\n"
	27	" 3 = two differential inputs\n");
	28
57256088 GR	29	/*
	30	* The PCF8591 control byte
	31	* 7 6 5 4 3 2 1 0
	32	* \| 0 \|AOEF\| AIP \| 0 \|AINC\| AICH \|
	33	*/
1da177e4 LT	34
	35	/* Analog Output Enable Flag (analog output active if 1) */
	36	#define PCF8591_CONTROL_AOEF 0x40
fb4504fe	37
57256088 GR	38	/*
	39	* Analog Input Programming
	40	* 0x00 = four single ended inputs
	41	* 0x10 = three differential inputs
	42	* 0x20 = single ended and differential mixed
	43	* 0x30 = two differential inputs
	44	*/
1da177e4 LT	45	#define PCF8591_CONTROL_AIP_MASK 0x30
	46
	47	/* Autoincrement Flag (switch on if 1) */
	48	#define PCF8591_CONTROL_AINC 0x04
	49
57256088 GR	50	/*
	51	* Channel selection
	52	* 0x00 = channel 0
	53	* 0x01 = channel 1
	54	* 0x02 = channel 2
	55	* 0x03 = channel 3
	56	*/
1da177e4 LT	57	#define PCF8591_CONTROL_AICH_MASK 0x03
	58
	59	/* Initial values */
	60	#define PCF8591_INIT_CONTROL ((input_mode << 4) \| PCF8591_CONTROL_AOEF)
	61	#define PCF8591_INIT_AOUT 0 /* DAC out = 0 */
	62
	63	/* Conversions */
57256088	64	#define REG_TO_SIGNED(reg) (((reg) & 0x80) ? ((reg) - 256) : (reg))
1da177e4 LT	65
1da177e4 LT	66	struct pcf8591_data {
4275fcd6	67	struct device *hwmon_dev;
5c085d36	68	struct mutex update_lock;
1da177e4 LT	69
	70	u8 control;
	71	u8 aout;
	72	};
	73
1da177e4 LT	74	static void pcf8591_init_client(struct i2c_client *client);
	75	static int pcf8591_read_channel(struct device *dev, int channel);
	76
1da177e4 LT	77	/* following are the sysfs callback functions */
1da177e4 LT	78	#define show_in_channel(channel) \
57256088 GR	79	static ssize_t show_in##channel##_input(struct device *dev, \
	80	struct device_attribute *attr, \
	81	char *buf) \
1da177e4 LT	82	{ \
	83	return sprintf(buf, "%d\n", pcf8591_read_channel(dev, channel));\
	84	} \
	85	static DEVICE_ATTR(in##channel##_input, S_IRUGO, \
	86	show_in##channel##_input, NULL);
	87
	88	show_in_channel(0);
	89	show_in_channel(1);
	90	show_in_channel(2);
	91	show_in_channel(3);
	92
309c675e JL	93	static ssize_t out0_output_show(struct device *dev,
309c675e JL	94	struct device_attribute attr, char buf)
1da177e4 LT	95	{
	96	struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
	97	return sprintf(buf, "%d\n", data->aout * 10);
	98	}
	99
309c675e JL	100	static ssize_t out0_output_store(struct device *dev,
	101	struct device_attribute *attr,
	102	const char *buf, size_t count)
1da177e4	103	{
57256088	104	unsigned long val;
1da177e4 LT	105	struct i2c_client *client = to_i2c_client(dev);
1da177e4 LT	106	struct pcf8591_data *data = i2c_get_clientdata(client);
57256088 GR	107	int err;
	108
	109	err = kstrtoul(buf, 10, &val);
	110	if (err)
	111	return err;
	112
	113	val /= 10;
	114	if (val > 255)
	115	return -EINVAL;
	116
	117	data->aout = val;
	118	i2c_smbus_write_byte_data(client, data->control, data->aout);
	119	return count;
1da177e4 LT	120	}
1da177e4 LT	121
309c675e	122	static DEVICE_ATTR_RW(out0_output);
1da177e4	123
309c675e	124	static ssize_t out0_enable_show(struct device *dev,
57256088	125	struct device_attribute attr, char buf)
1da177e4 LT	126	{
	127	struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
	128	return sprintf(buf, "%u\n", !(!(data->control & PCF8591_CONTROL_AOEF)));
	129	}
	130
309c675e JL	131	static ssize_t out0_enable_store(struct device *dev,
	132	struct device_attribute *attr,
	133	const char *buf, size_t count)
1da177e4 LT	134	{
	135	struct i2c_client *client = to_i2c_client(dev);
	136	struct pcf8591_data *data = i2c_get_clientdata(client);
57256088 GR	137	unsigned long val;
	138	int err;
	139
	140	err = kstrtoul(buf, 10, &val);
	141	if (err)
	142	return err;
1da177e4	143
5c085d36	144	mutex_lock(&data->update_lock);
1da177e4 LT	145	if (val)
	146	data->control \|= PCF8591_CONTROL_AOEF;
	147	else
	148	data->control &= ~PCF8591_CONTROL_AOEF;
	149	i2c_smbus_write_byte(client, data->control);
5c085d36	150	mutex_unlock(&data->update_lock);
1da177e4 LT	151	return count;
	152	}
	153
309c675e	154	static DEVICE_ATTR_RW(out0_enable);
1da177e4	155
7d9db67f JD	156	static struct attribute *pcf8591_attributes[] = {
	157	&dev_attr_out0_enable.attr,
	158	&dev_attr_out0_output.attr,
	159	&dev_attr_in0_input.attr,
	160	&dev_attr_in1_input.attr,
	161	NULL
	162	};
	163
	164	static const struct attribute_group pcf8591_attr_group = {
	165	.attrs = pcf8591_attributes,
	166	};
	167
	168	static struct attribute *pcf8591_attributes_opt[] = {
	169	&dev_attr_in2_input.attr,
	170	&dev_attr_in3_input.attr,
	171	NULL
	172	};
	173
	174	static const struct attribute_group pcf8591_attr_group_opt = {
	175	.attrs = pcf8591_attributes_opt,
	176	};
	177
1da177e4 LT	178	/*
	179	* Real code
	180	*/
1da177e4	181
67487038	182	static int pcf8591_probe(struct i2c_client *client)
8b77e6ac JD	183	{
	184	struct pcf8591_data *data;
	185	int err;
1da177e4	186
60c2b569 GR	187	data = devm_kzalloc(&client->dev, sizeof(struct pcf8591_data),
	188	GFP_KERNEL);
	189	if (!data)
	190	return -ENOMEM;
fb4504fe	191
f741f673	192	i2c_set_clientdata(client, data);
5c085d36	193	mutex_init(&data->update_lock);
1da177e4	194
1da177e4	195	/* Initialize the PCF8591 chip */
f741f673	196	pcf8591_init_client(client);
1da177e4 LT	197
1da177e4 LT	198	/* Register sysfs hooks */
f741f673	199	err = sysfs_create_group(&client->dev.kobj, &pcf8591_attr_group);
7d9db67f	200	if (err)
60c2b569	201	return err;
1da177e4 LT	202
1da177e4 LT	203	/* Register input2 if not in "two differential inputs" mode */
7d9db67f	204	if (input_mode != 3) {
57256088 GR	205	err = device_create_file(&client->dev, &dev_attr_in2_input);
57256088 GR	206	if (err)
7d9db67f JD	207	goto exit_sysfs_remove;
	208	}
	209
1da177e4	210	/* Register input3 only in "four single ended inputs" mode */
7d9db67f	211	if (input_mode == 0) {
57256088 GR	212	err = device_create_file(&client->dev, &dev_attr_in3_input);
57256088 GR	213	if (err)
7d9db67f JD	214	goto exit_sysfs_remove;
	215	}
	216
4275fcd6 JD	217	data->hwmon_dev = hwmon_device_register(&client->dev);
	218	if (IS_ERR(data->hwmon_dev)) {
	219	err = PTR_ERR(data->hwmon_dev);
	220	goto exit_sysfs_remove;
	221	}
	222
1da177e4	223	return 0;
1da177e4	224
7d9db67f	225	exit_sysfs_remove:
f741f673 JD	226	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
f741f673 JD	227	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
1da177e4 LT	228	return err;
	229	}
	230
ed5c2f5f	231	static void pcf8591_remove(struct i2c_client *client)
1da177e4	232	{
4275fcd6 JD	233	struct pcf8591_data *data = i2c_get_clientdata(client);
	234
	235	hwmon_device_unregister(data->hwmon_dev);
7d9db67f JD	236	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
7d9db67f JD	237	sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
1da177e4 LT	238	}
	239
	240	/* Called when we have found a new PCF8591. */
	241	static void pcf8591_init_client(struct i2c_client *client)
	242	{
	243	struct pcf8591_data *data = i2c_get_clientdata(client);
	244	data->control = PCF8591_INIT_CONTROL;
	245	data->aout = PCF8591_INIT_AOUT;
	246
	247	i2c_smbus_write_byte_data(client, data->control, data->aout);
fb4504fe	248
57256088 GR	249	/*
	250	* The first byte transmitted contains the conversion code of the
	251	* previous read cycle. FLUSH IT!
	252	*/
1da177e4 LT	253	i2c_smbus_read_byte(client);
	254	}
	255
	256	static int pcf8591_read_channel(struct device *dev, int channel)
	257	{
	258	u8 value;
	259	struct i2c_client *client = to_i2c_client(dev);
	260	struct pcf8591_data *data = i2c_get_clientdata(client);
	261
5c085d36	262	mutex_lock(&data->update_lock);
1da177e4 LT	263
	264	if ((data->control & PCF8591_CONTROL_AICH_MASK) != channel) {
	265	data->control = (data->control & ~PCF8591_CONTROL_AICH_MASK)
	266	\| channel;
	267	i2c_smbus_write_byte(client, data->control);
fb4504fe	268
57256088 GR	269	/*
	270	* The first byte transmitted contains the conversion code of
	271	* the previous read cycle. FLUSH IT!
	272	*/
1da177e4 LT	273	i2c_smbus_read_byte(client);
	274	}
	275	value = i2c_smbus_read_byte(client);
	276
5c085d36	277	mutex_unlock(&data->update_lock);
1da177e4 LT	278
	279	if ((channel == 2 && input_mode == 2) \|\|
	280	(channel != 3 && (input_mode == 1 \|\| input_mode == 3)))
7fe83ad8	281	return 10 * REG_TO_SIGNED(value);
1da177e4	282	else
7fe83ad8	283	return 10 * value;
1da177e4 LT	284	}
1da177e4 LT	285
8b77e6ac JD	286	static const struct i2c_device_id pcf8591_id[] = {
	287	{ "pcf8591", 0 },
	288	{ }
	289	};
	290	MODULE_DEVICE_TABLE(i2c, pcf8591_id);
	291
	292	static struct i2c_driver pcf8591_driver = {
	293	.driver = {
	294	.name = "pcf8591",
	295	},
67487038	296	.probe_new = pcf8591_probe,
8b77e6ac JD	297	.remove = pcf8591_remove,
8b77e6ac JD	298	.id_table = pcf8591_id,
8b77e6ac JD	299	};
8b77e6ac JD	300
1da177e4 LT	301	static int __init pcf8591_init(void)
	302	{
	303	if (input_mode < 0 \|\| input_mode > 3) {
2caec134	304	pr_warn("invalid input_mode (%d)\n", input_mode);
1da177e4 LT	305	input_mode = 0;
	306	}
	307	return i2c_add_driver(&pcf8591_driver);
	308	}
	309
	310	static void __exit pcf8591_exit(void)
	311	{
	312	i2c_del_driver(&pcf8591_driver);
	313	}
	314
	315	MODULE_AUTHOR("Aurelien Jarno <[email protected]>");
	316	MODULE_DESCRIPTION("PCF8591 driver");
	317	MODULE_LICENSE("GPL");
	318
	319	module_init(pcf8591_init);
	320	module_exit(pcf8591_exit);