[deliverable/linux.git] / drivers / iio / potentiometer / mcp4531.c

/*
 * Industrial I/O driver for Microchip digital potentiometers
 * Copyright (c) 2015  Axentia Technologies AB
 * Author: Peter Rosin <peda@axentia.se>
 *
 * Datasheet: http://www.microchip.com/downloads/en/DeviceDoc/22096b.pdf
 *
 * DEVID	#Wipers	#Positions	Resistor Opts (kOhm)	i2c address
 * mcp4531	1	129		5, 10, 50, 100          010111x
 * mcp4532	1	129		5, 10, 50, 100          01011xx
 * mcp4551	1	257		5, 10, 50, 100          010111x
 * mcp4552	1	257		5, 10, 50, 100          01011xx
 * mcp4631	2	129		5, 10, 50, 100          0101xxx
 * mcp4632	2	129		5, 10, 50, 100          01011xx
 * mcp4651	2	257		5, 10, 50, 100          0101xxx
 * mcp4652	2	257		5, 10, 50, 100          01011xx
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/err.h>

#include <linux/iio/iio.h>

struct mcp4531_cfg {
	int wipers;
	int max_pos;
	int kohms;
};

enum mcp4531_type {
	MCP453x_502,
	MCP453x_103,
	MCP453x_503,
	MCP453x_104,
	MCP455x_502,
	MCP455x_103,
	MCP455x_503,
	MCP455x_104,
	MCP463x_502,
	MCP463x_103,
	MCP463x_503,
	MCP463x_104,
	MCP465x_502,
	MCP465x_103,
	MCP465x_503,
	MCP465x_104,
};

static const struct mcp4531_cfg mcp4531_cfg[] = {
	[MCP453x_502] = { .wipers = 1, .max_pos = 128, .kohms =   5, },
	[MCP453x_103] = { .wipers = 1, .max_pos = 128, .kohms =  10, },
	[MCP453x_503] = { .wipers = 1, .max_pos = 128, .kohms =  50, },
	[MCP453x_104] = { .wipers = 1, .max_pos = 128, .kohms = 100, },
	[MCP455x_502] = { .wipers = 1, .max_pos = 256, .kohms =   5, },
	[MCP455x_103] = { .wipers = 1, .max_pos = 256, .kohms =  10, },
	[MCP455x_503] = { .wipers = 1, .max_pos = 256, .kohms =  50, },
	[MCP455x_104] = { .wipers = 1, .max_pos = 256, .kohms = 100, },
	[MCP463x_502] = { .wipers = 2, .max_pos = 128, .kohms =   5, },
	[MCP463x_103] = { .wipers = 2, .max_pos = 128, .kohms =  10, },
	[MCP463x_503] = { .wipers = 2, .max_pos = 128, .kohms =  50, },
	[MCP463x_104] = { .wipers = 2, .max_pos = 128, .kohms = 100, },
	[MCP465x_502] = { .wipers = 2, .max_pos = 256, .kohms =   5, },
	[MCP465x_103] = { .wipers = 2, .max_pos = 256, .kohms =  10, },
	[MCP465x_503] = { .wipers = 2, .max_pos = 256, .kohms =  50, },
	[MCP465x_104] = { .wipers = 2, .max_pos = 256, .kohms = 100, },
};

#define MCP4531_WRITE (0 << 2)
#define MCP4531_INCR  (1 << 2)
#define MCP4531_DECR  (2 << 2)
#define MCP4531_READ  (3 << 2)

#define MCP4531_WIPER_SHIFT (4)

struct mcp4531_data {
	struct i2c_client *client;
	unsigned long devid;
};

#define MCP4531_CHANNEL(ch) {					\
	.type = IIO_RESISTANCE,					\
	.indexed = 1,						\
	.output = 1,						\
	.channel = (ch),					\
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
}

static const struct iio_chan_spec mcp4531_channels[] = {
	MCP4531_CHANNEL(0),
	MCP4531_CHANNEL(1),
};

static int mcp4531_read_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *chan,
			    int *val, int *val2, long mask)
{
	struct mcp4531_data *data = iio_priv(indio_dev);
	int address = chan->channel << MCP4531_WIPER_SHIFT;
	s32 ret;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		ret = i2c_smbus_read_word_swapped(data->client,
						  MCP4531_READ | address);
		if (ret < 0)
			return ret;
		*val = ret;
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
		*val = 1000 * mcp4531_cfg[data->devid].kohms;
		*val2 = mcp4531_cfg[data->devid].max_pos;
		return IIO_VAL_FRACTIONAL;
	}

	return -EINVAL;
}

static int mcp4531_write_raw(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *chan,
			     int val, int val2, long mask)
{
	struct mcp4531_data *data = iio_priv(indio_dev);
	int address = chan->channel << MCP4531_WIPER_SHIFT;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		if (val > mcp4531_cfg[data->devid].max_pos || val < 0)
			return -EINVAL;
		break;
	default:
		return -EINVAL;
	}

	return i2c_smbus_write_byte_data(data->client,
					 MCP4531_WRITE | address | (val >> 8),
					 val & 0xff);
}

static const struct iio_info mcp4531_info = {
	.read_raw = mcp4531_read_raw,
	.write_raw = mcp4531_write_raw,
	.driver_module = THIS_MODULE,
};

static int mcp4531_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct device *dev = &client->dev;
	unsigned long devid = id->driver_data;
	struct mcp4531_data *data;
	struct iio_dev *indio_dev;

	if (!i2c_check_functionality(client->adapter,
				     I2C_FUNC_SMBUS_WORD_DATA)) {
		dev_err(dev, "SMBUS Word Data not supported\n");
		return -EOPNOTSUPP;
	}

	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
	if (!indio_dev)
		return -ENOMEM;
	data = iio_priv(indio_dev);
	i2c_set_clientdata(client, indio_dev);
	data->client = client;
	data->devid = devid;

	indio_dev->dev.parent = dev;
	indio_dev->info = &mcp4531_info;
	indio_dev->channels = mcp4531_channels;
	indio_dev->num_channels = mcp4531_cfg[devid].wipers;
	indio_dev->name = client->name;

	return devm_iio_device_register(dev, indio_dev);
}

static const struct i2c_device_id mcp4531_id[] = {
	{ "mcp4531-502", MCP453x_502 },
	{ "mcp4531-103", MCP453x_103 },
	{ "mcp4531-503", MCP453x_503 },
	{ "mcp4531-104", MCP453x_104 },
	{ "mcp4532-502", MCP453x_502 },
	{ "mcp4532-103", MCP453x_103 },
	{ "mcp4532-503", MCP453x_503 },
	{ "mcp4532-104", MCP453x_104 },
	{ "mcp4551-502", MCP455x_502 },
	{ "mcp4551-103", MCP455x_103 },
	{ "mcp4551-503", MCP455x_503 },
	{ "mcp4551-104", MCP455x_104 },
	{ "mcp4552-502", MCP455x_502 },
	{ "mcp4552-103", MCP455x_103 },
	{ "mcp4552-503", MCP455x_503 },
	{ "mcp4552-104", MCP455x_104 },
	{ "mcp4631-502", MCP463x_502 },
	{ "mcp4631-103", MCP463x_103 },
	{ "mcp4631-503", MCP463x_503 },
	{ "mcp4631-104", MCP463x_104 },
	{ "mcp4632-502", MCP463x_502 },
	{ "mcp4632-103", MCP463x_103 },
	{ "mcp4632-503", MCP463x_503 },
	{ "mcp4632-104", MCP463x_104 },
	{ "mcp4651-502", MCP465x_502 },
	{ "mcp4651-103", MCP465x_103 },
	{ "mcp4651-503", MCP465x_503 },
	{ "mcp4651-104", MCP465x_104 },
	{ "mcp4652-502", MCP465x_502 },
	{ "mcp4652-103", MCP465x_103 },
	{ "mcp4652-503", MCP465x_503 },
	{ "mcp4652-104", MCP465x_104 },
	{}
};
MODULE_DEVICE_TABLE(i2c, mcp4531_id);

static struct i2c_driver mcp4531_driver = {
	.driver = {
		.name	= "mcp4531",
	},
	.probe		= mcp4531_probe,
	.id_table	= mcp4531_id,
};

module_i2c_driver(mcp4531_driver);

MODULE_AUTHOR("Peter Rosin <peda@axentia.se>");
MODULE_DESCRIPTION("MCP4531 digital potentiometer");
MODULE_LICENSE("GPL");
Commit	Line	Data
c05dc2cc PR	1	/*
	2	* Industrial I/O driver for Microchip digital potentiometers
	3	* Copyright (c) 2015 Axentia Technologies AB
	4	* Author: Peter Rosin <peda@axentia.se>
	5	*
	6	* Datasheet: http://www.microchip.com/downloads/en/DeviceDoc/22096b.pdf
	7	*
	8	* DEVID #Wipers #Positions Resistor Opts (kOhm) i2c address
	9	* mcp4531 1 129 5, 10, 50, 100 010111x
	10	* mcp4532 1 129 5, 10, 50, 100 01011xx
	11	* mcp4551 1 257 5, 10, 50, 100 010111x
	12	* mcp4552 1 257 5, 10, 50, 100 01011xx
	13	* mcp4631 2 129 5, 10, 50, 100 0101xxx
	14	* mcp4632 2 129 5, 10, 50, 100 01011xx
	15	* mcp4651 2 257 5, 10, 50, 100 0101xxx
	16	* mcp4652 2 257 5, 10, 50, 100 01011xx
	17	*
	18	* This program is free software; you can redistribute it and/or modify it
	19	* under the terms of the GNU General Public License version 2 as published by
	20	* the Free Software Foundation.
	21	*/
	22
	23	#include <linux/module.h>
	24	#include <linux/i2c.h>
	25	#include <linux/err.h>
	26
	27	#include <linux/iio/iio.h>
	28
	29	struct mcp4531_cfg {
	30	int wipers;
	31	int max_pos;
	32	int kohms;
	33	};
	34
	35	enum mcp4531_type {
	36	MCP453x_502,
	37	MCP453x_103,
	38	MCP453x_503,
	39	MCP453x_104,
	40	MCP455x_502,
	41	MCP455x_103,
	42	MCP455x_503,
	43	MCP455x_104,
	44	MCP463x_502,
	45	MCP463x_103,
	46	MCP463x_503,
	47	MCP463x_104,
	48	MCP465x_502,
	49	MCP465x_103,
	50	MCP465x_503,
	51	MCP465x_104,
	52	};
	53
	54	static const struct mcp4531_cfg mcp4531_cfg[] = {
	55	[MCP453x_502] = { .wipers = 1, .max_pos = 128, .kohms = 5, },
	56	[MCP453x_103] = { .wipers = 1, .max_pos = 128, .kohms = 10, },
	57	[MCP453x_503] = { .wipers = 1, .max_pos = 128, .kohms = 50, },
	58	[MCP453x_104] = { .wipers = 1, .max_pos = 128, .kohms = 100, },
	59	[MCP455x_502] = { .wipers = 1, .max_pos = 256, .kohms = 5, },
	60	[MCP455x_103] = { .wipers = 1, .max_pos = 256, .kohms = 10, },
	61	[MCP455x_503] = { .wipers = 1, .max_pos = 256, .kohms = 50, },
	62	[MCP455x_104] = { .wipers = 1, .max_pos = 256, .kohms = 100, },
	63	[MCP463x_502] = { .wipers = 2, .max_pos = 128, .kohms = 5, },
	64	[MCP463x_103] = { .wipers = 2, .max_pos = 128, .kohms = 10, },
65	[MCP463x_503] = { .wipers = 2, .max_pos = 128, .kohms = 50, },
66	[MCP463x_104] = { .wipers = 2, .max_pos = 128, .kohms = 100, },
67	[MCP465x_502] = { .wipers = 2, .max_pos = 256, .kohms = 5, },
68	[MCP465x_103] = { .wipers = 2, .max_pos = 256, .kohms = 10, },
69	[MCP465x_503] = { .wipers = 2, .max_pos = 256, .kohms = 50, },
70	[MCP465x_104] = { .wipers = 2, .max_pos = 256, .kohms = 100, },
71	};
72
73	#define MCP4531_WRITE (0 << 2)
74	#define MCP4531_INCR (1 << 2)
75	#define MCP4531_DECR (2 << 2)
76	#define MCP4531_READ (3 << 2)
77
78	#define MCP4531_WIPER_SHIFT (4)
79
80	struct mcp4531_data {
81	struct i2c_client *client;
82	unsigned long devid;
83	};
84
85	#define MCP4531_CHANNEL(ch) { \
86	.type = IIO_RESISTANCE, \
87	.indexed = 1, \
88	.output = 1, \
89	.channel = (ch), \
90	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
91	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
92	}
93
94	static const struct iio_chan_spec mcp4531_channels[] = {
95	MCP4531_CHANNEL(0),
96	MCP4531_CHANNEL(1),
97	};
98
99	static int mcp4531_read_raw(struct iio_dev *indio_dev,
100	struct iio_chan_spec const *chan,
101	int val, int val2, long mask)
102	{
103	struct mcp4531_data *data = iio_priv(indio_dev);
104	int address = chan->channel << MCP4531_WIPER_SHIFT;
105	s32 ret;
106
107	switch (mask) {
108	case IIO_CHAN_INFO_RAW:
109	ret = i2c_smbus_read_word_swapped(data->client,
110	MCP4531_READ \| address);
111	if (ret < 0)
112	return ret;
113	*val = ret;
114	return IIO_VAL_INT;
115	case IIO_CHAN_INFO_SCALE:
116	val = 1000 mcp4531_cfg[data->devid].kohms;
117	*val2 = mcp4531_cfg[data->devid].max_pos;
118	return IIO_VAL_FRACTIONAL;
119	}
120
121	return -EINVAL;
122	}
123
124	static int mcp4531_write_raw(struct iio_dev *indio_dev,
125	struct iio_chan_spec const *chan,
126	int val, int val2, long mask)
127	{
128	struct mcp4531_data *data = iio_priv(indio_dev);
129	int address = chan->channel << MCP4531_WIPER_SHIFT;
130
131	switch (mask) {
132	case IIO_CHAN_INFO_RAW:
133	if (val > mcp4531_cfg[data->devid].max_pos \|\| val < 0)
134	return -EINVAL;
135	break;
136	default:
137	return -EINVAL;
138	}
139
140	return i2c_smbus_write_byte_data(data->client,
141	MCP4531_WRITE \| address \| (val >> 8),
142	val & 0xff);
143	}
144
145	static const struct iio_info mcp4531_info = {
146	.read_raw = mcp4531_read_raw,
147	.write_raw = mcp4531_write_raw,
148	.driver_module = THIS_MODULE,
149	};
150
151	static int mcp4531_probe(struct i2c_client *client,
152	const struct i2c_device_id *id)
153	{
154	struct device *dev = &client->dev;
155	unsigned long devid = id->driver_data;
156	struct mcp4531_data *data;
157	struct iio_dev *indio_dev;
158
159	if (!i2c_check_functionality(client->adapter,
160	I2C_FUNC_SMBUS_WORD_DATA)) {
161	dev_err(dev, "SMBUS Word Data not supported\n");
f8d9d3b4	162	return -EOPNOTSUPP;
c05dc2cc PR	163	}
	164
	165	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
	166	if (!indio_dev)
	167	return -ENOMEM;
	168	data = iio_priv(indio_dev);
	169	i2c_set_clientdata(client, indio_dev);
	170	data->client = client;
	171	data->devid = devid;
	172
	173	indio_dev->dev.parent = dev;
	174	indio_dev->info = &mcp4531_info;
	175	indio_dev->channels = mcp4531_channels;
	176	indio_dev->num_channels = mcp4531_cfg[devid].wipers;
	177	indio_dev->name = client->name;
	178
	179	return devm_iio_device_register(dev, indio_dev);
	180	}
	181
	182	static const struct i2c_device_id mcp4531_id[] = {
	183	{ "mcp4531-502", MCP453x_502 },
	184	{ "mcp4531-103", MCP453x_103 },
	185	{ "mcp4531-503", MCP453x_503 },
	186	{ "mcp4531-104", MCP453x_104 },
	187	{ "mcp4532-502", MCP453x_502 },
	188	{ "mcp4532-103", MCP453x_103 },
	189	{ "mcp4532-503", MCP453x_503 },
	190	{ "mcp4532-104", MCP453x_104 },
	191	{ "mcp4551-502", MCP455x_502 },
	192	{ "mcp4551-103", MCP455x_103 },
	193	{ "mcp4551-503", MCP455x_503 },
	194	{ "mcp4551-104", MCP455x_104 },
	195	{ "mcp4552-502", MCP455x_502 },
	196	{ "mcp4552-103", MCP455x_103 },
	197	{ "mcp4552-503", MCP455x_503 },
	198	{ "mcp4552-104", MCP455x_104 },
	199	{ "mcp4631-502", MCP463x_502 },
	200	{ "mcp4631-103", MCP463x_103 },
	201	{ "mcp4631-503", MCP463x_503 },
	202	{ "mcp4631-104", MCP463x_104 },
	203	{ "mcp4632-502", MCP463x_502 },
	204	{ "mcp4632-103", MCP463x_103 },
	205	{ "mcp4632-503", MCP463x_503 },
	206	{ "mcp4632-104", MCP463x_104 },
	207	{ "mcp4651-502", MCP465x_502 },
	208	{ "mcp4651-103", MCP465x_103 },
	209	{ "mcp4651-503", MCP465x_503 },
	210	{ "mcp4651-104", MCP465x_104 },
	211	{ "mcp4652-502", MCP465x_502 },
	212	{ "mcp4652-103", MCP465x_103 },
	213	{ "mcp4652-503", MCP465x_503 },
	214	{ "mcp4652-104", MCP465x_104 },
	215	{}
	216	};
	217	MODULE_DEVICE_TABLE(i2c, mcp4531_id);
	218
	219	static struct i2c_driver mcp4531_driver = {
	220	.driver = {
	221	.name = "mcp4531",
	222	},
	223	.probe = mcp4531_probe,
	224	.id_table = mcp4531_id,
	225	};
	226
227	module_i2c_driver(mcp4531_driver);
228
229	MODULE_AUTHOR("Peter Rosin <peda@axentia.se>");
230	MODULE_DESCRIPTION("MCP4531 digital potentiometer");
231	MODULE_LICENSE("GPL");