[linux.git] / drivers / iio / dac / ds4424.c

/*
 * Maxim Integrated
 * 7-bit, Multi-Channel Sink/Source Current DAC Driver
 * Copyright (C) 2017 Maxim Integrated
 *
 * 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/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/regulator/consumer.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/iio/iio.h>
#include <linux/iio/driver.h>
#include <linux/iio/machine.h>
#include <linux/iio/consumer.h>

#define DS4422_MAX_DAC_CHANNELS		2
#define DS4424_MAX_DAC_CHANNELS		4

#define DS4424_DAC_ADDR(chan)   ((chan) + 0xf8)
#define DS4424_SOURCE_I		1
#define DS4424_SINK_I		0

#define DS4424_CHANNEL(chan) { \
	.type = IIO_CURRENT, \
	.indexed = 1, \
	.output = 1, \
	.channel = chan, \
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
}

/*
 * DS4424 DAC control register 8 bits
 * [7]		0: to sink; 1: to source
 * [6:0]	steps to sink/source
 * bit[7] looks like a sign bit, but the value of the register is
 * not a two's complement code considering the bit[6:0] is a absolute
 * distance from the zero point.
 */
union ds4424_raw_data {
	struct {
		u8 dx:7;
		u8 source_bit:1;
	};
	u8 bits;
};

enum ds4424_device_ids {
	ID_DS4422,
	ID_DS4424,
};

struct ds4424_data {
	struct i2c_client *client;
	struct mutex lock;
	uint8_t save[DS4424_MAX_DAC_CHANNELS];
	struct regulator *vcc_reg;
	uint8_t raw[DS4424_MAX_DAC_CHANNELS];
};

static const struct iio_chan_spec ds4424_channels[] = {
	DS4424_CHANNEL(0),
	DS4424_CHANNEL(1),
	DS4424_CHANNEL(2),
	DS4424_CHANNEL(3),
};

static int ds4424_get_value(struct iio_dev *indio_dev,
			     int *val, int channel)
{
	struct ds4424_data *data = iio_priv(indio_dev);
	int ret;

	mutex_lock(&data->lock);
	ret = i2c_smbus_read_byte_data(data->client, DS4424_DAC_ADDR(channel));
	if (ret < 0)
		goto fail;

	*val = ret;

fail:
	mutex_unlock(&data->lock);
	return ret;
}

static int ds4424_set_value(struct iio_dev *indio_dev,
			     int val, struct iio_chan_spec const *chan)
{
	struct ds4424_data *data = iio_priv(indio_dev);
	int ret;

	mutex_lock(&data->lock);
	ret = i2c_smbus_write_byte_data(data->client,
			DS4424_DAC_ADDR(chan->channel), val);
	if (ret < 0)
		goto fail;

	data->raw[chan->channel] = val;

fail:
	mutex_unlock(&data->lock);
	return ret;
}

static int ds4424_read_raw(struct iio_dev *indio_dev,
			   struct iio_chan_spec const *chan,
			   int *val, int *val2, long mask)
{
	union ds4424_raw_data raw;
	int ret;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		ret = ds4424_get_value(indio_dev, val, chan->channel);
		if (ret < 0) {
			pr_err("%s : ds4424_get_value returned %d\n",
							__func__, ret);
			return ret;
		}
		raw.bits = *val;
		*val = raw.dx;
		if (raw.source_bit == DS4424_SINK_I)
			*val = -*val;
		return IIO_VAL_INT;

	default:
		return -EINVAL;
	}
}

static int ds4424_write_raw(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *chan,
			     int val, int val2, long mask)
{
	union ds4424_raw_data raw;

	if (val2 != 0)
		return -EINVAL;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		if (val < S8_MIN || val > S8_MAX)
			return -EINVAL;

		if (val > 0) {
			raw.source_bit = DS4424_SOURCE_I;
			raw.dx = val;
		} else {
			raw.source_bit = DS4424_SINK_I;
			raw.dx = -val;
		}

		return ds4424_set_value(indio_dev, raw.bits, chan);

	default:
		return -EINVAL;
	}
}

static int ds4424_verify_chip(struct iio_dev *indio_dev)
{
	int ret, val;

	ret = ds4424_get_value(indio_dev, &val, DS4424_DAC_ADDR(0));
	if (ret < 0)
		dev_err(&indio_dev->dev,
				"%s failed. ret: %d\n", __func__, ret);

	return ret;
}

static int __maybe_unused ds4424_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	struct ds4424_data *data = iio_priv(indio_dev);
	int ret = 0;
	int i;

	for (i = 0; i < indio_dev->num_channels; i++) {
		data->save[i] = data->raw[i];
		ret = ds4424_set_value(indio_dev, 0,
				&indio_dev->channels[i]);
		if (ret < 0)
			return ret;
	}
	return ret;
}

static int __maybe_unused ds4424_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	struct ds4424_data *data = iio_priv(indio_dev);
	int ret = 0;
	int i;

	for (i = 0; i < indio_dev->num_channels; i++) {
		ret = ds4424_set_value(indio_dev, data->save[i],
				&indio_dev->channels[i]);
		if (ret < 0)
			return ret;
	}
	return ret;
}

static SIMPLE_DEV_PM_OPS(ds4424_pm_ops, ds4424_suspend, ds4424_resume);

static const struct iio_info ds4424_info = {
	.read_raw = ds4424_read_raw,
	.write_raw = ds4424_write_raw,
};

static int ds4424_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct ds4424_data *data;
	struct iio_dev *indio_dev;
	int ret;

	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	if (!indio_dev) {
		dev_err(&client->dev, "iio dev alloc failed.\n");
		return -ENOMEM;
	}

	data = iio_priv(indio_dev);
	i2c_set_clientdata(client, indio_dev);
	data->client = client;
	indio_dev->name = id->name;
	indio_dev->dev.of_node = client->dev.of_node;
	indio_dev->dev.parent = &client->dev;

	if (!client->dev.of_node) {
		dev_err(&client->dev,
				"Not found DT.\n");
		return -ENODEV;
	}

	data->vcc_reg = devm_regulator_get(&client->dev, "vcc");
	if (IS_ERR(data->vcc_reg)) {
		dev_err(&client->dev,
			"Failed to get vcc-supply regulator. err: %ld\n",
				PTR_ERR(data->vcc_reg));
		return PTR_ERR(data->vcc_reg);
	}

	mutex_init(&data->lock);
	ret = regulator_enable(data->vcc_reg);
	if (ret < 0) {
		dev_err(&client->dev,
				"Unable to enable the regulator.\n");
		return ret;
	}

	usleep_range(1000, 1200);
	ret = ds4424_verify_chip(indio_dev);
	if (ret < 0)
		goto fail;

	switch (id->driver_data) {
	case ID_DS4422:
		indio_dev->num_channels = DS4422_MAX_DAC_CHANNELS;
		break;
	case ID_DS4424:
		indio_dev->num_channels = DS4424_MAX_DAC_CHANNELS;
		break;
	default:
		dev_err(&client->dev,
				"ds4424: Invalid chip id.\n");
		ret = -ENXIO;
		goto fail;
	}

	indio_dev->channels = ds4424_channels;
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->info = &ds4424_info;

	ret = iio_device_register(indio_dev);
	if (ret < 0) {
		dev_err(&client->dev,
				"iio_device_register failed. ret: %d\n", ret);
		goto fail;
	}

	return ret;

fail:
	regulator_disable(data->vcc_reg);
	return ret;
}

static int ds4424_remove(struct i2c_client *client)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	struct ds4424_data *data = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);
	regulator_disable(data->vcc_reg);

	return 0;
}

static const struct i2c_device_id ds4424_id[] = {
	{ "ds4422", ID_DS4422 },
	{ "ds4424", ID_DS4424 },
	{ }
};

MODULE_DEVICE_TABLE(i2c, ds4424_id);

static const struct of_device_id ds4424_of_match[] = {
	{ .compatible = "maxim,ds4422" },
	{ .compatible = "maxim,ds4424" },
	{ },
};

MODULE_DEVICE_TABLE(of, ds4424_of_match);

static struct i2c_driver ds4424_driver = {
	.driver = {
		.name	= "ds4424",
		.of_match_table = ds4424_of_match,
		.pm     = &ds4424_pm_ops,
	},
	.probe		= ds4424_probe,
	.remove		= ds4424_remove,
	.id_table	= ds4424_id,
};
module_i2c_driver(ds4424_driver);

MODULE_DESCRIPTION("Maxim DS4424 DAC Driver");
MODULE_AUTHOR("Ismail H. Kose <[email protected]>");
MODULE_AUTHOR("Vishal Sood <[email protected]>");
MODULE_AUTHOR("David Jung <[email protected]>");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
d632a2bd IK	1	/*
	2	* Maxim Integrated
	3	* 7-bit, Multi-Channel Sink/Source Current DAC Driver
	4	* Copyright (C) 2017 Maxim Integrated
	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 version 2 as
	8	* published by the Free Software Foundation.
	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/module.h>
	13	#include <linux/i2c.h>
	14	#include <linux/regulator/consumer.h>
	15	#include <linux/err.h>
	16	#include <linux/delay.h>
	17	#include <linux/iio/iio.h>
	18	#include <linux/iio/driver.h>
	19	#include <linux/iio/machine.h>
	20	#include <linux/iio/consumer.h>
	21
	22	#define DS4422_MAX_DAC_CHANNELS 2
	23	#define DS4424_MAX_DAC_CHANNELS 4
	24
	25	#define DS4424_DAC_ADDR(chan) ((chan) + 0xf8)
	26	#define DS4424_SOURCE_I 1
	27	#define DS4424_SINK_I 0
	28
	29	#define DS4424_CHANNEL(chan) { \
	30	.type = IIO_CURRENT, \
	31	.indexed = 1, \
	32	.output = 1, \
	33	.channel = chan, \
	34	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	35	}
	36
	37	/*
	38	* DS4424 DAC control register 8 bits
	39	* [7] 0: to sink; 1: to source
	40	* [6:0] steps to sink/source
	41	* bit[7] looks like a sign bit, but the value of the register is
	42	* not a two's complement code considering the bit[6:0] is a absolute
	43	* distance from the zero point.
	44	*/
	45	union ds4424_raw_data {
	46	struct {
	47	u8 dx:7;
	48	u8 source_bit:1;
	49	};
	50	u8 bits;
	51	};
	52
	53	enum ds4424_device_ids {
	54	ID_DS4422,
	55	ID_DS4424,
	56	};
	57
	58	struct ds4424_data {
	59	struct i2c_client *client;
	60	struct mutex lock;
	61	uint8_t save[DS4424_MAX_DAC_CHANNELS];
	62	struct regulator *vcc_reg;
	63	uint8_t raw[DS4424_MAX_DAC_CHANNELS];
	64	};
65
66	static const struct iio_chan_spec ds4424_channels[] = {
67	DS4424_CHANNEL(0),
68	DS4424_CHANNEL(1),
69	DS4424_CHANNEL(2),
70	DS4424_CHANNEL(3),
71	};
72
73	static int ds4424_get_value(struct iio_dev *indio_dev,
74	int *val, int channel)
75	{
76	struct ds4424_data *data = iio_priv(indio_dev);
77	int ret;
78
79	mutex_lock(&data->lock);
80	ret = i2c_smbus_read_byte_data(data->client, DS4424_DAC_ADDR(channel));
81	if (ret < 0)
82	goto fail;
83
84	*val = ret;
85
86	fail:
87	mutex_unlock(&data->lock);
88	return ret;
89	}
90
91	static int ds4424_set_value(struct iio_dev *indio_dev,
92	int val, struct iio_chan_spec const *chan)
93	{
94	struct ds4424_data *data = iio_priv(indio_dev);
95	int ret;
96
97	mutex_lock(&data->lock);
98	ret = i2c_smbus_write_byte_data(data->client,
99	DS4424_DAC_ADDR(chan->channel), val);
100	if (ret < 0)
101	goto fail;
102
103	data->raw[chan->channel] = val;
104
105	fail:
106	mutex_unlock(&data->lock);
107	return ret;
108	}
109
110	static int ds4424_read_raw(struct iio_dev *indio_dev,
111	struct iio_chan_spec const *chan,
112	int val, int val2, long mask)
113	{
114	union ds4424_raw_data raw;
115	int ret;
116
117	switch (mask) {
118	case IIO_CHAN_INFO_RAW:
119	ret = ds4424_get_value(indio_dev, val, chan->channel);
120	if (ret < 0) {
121	pr_err("%s : ds4424_get_value returned %d\n",
122	__func__, ret);
123	return ret;
124	}
125	raw.bits = *val;
126	*val = raw.dx;
127	if (raw.source_bit == DS4424_SINK_I)
128	val = -val;
129	return IIO_VAL_INT;
130
131	default:
132	return -EINVAL;
133	}
134	}
135
136	static int ds4424_write_raw(struct iio_dev *indio_dev,
137	struct iio_chan_spec const *chan,
138	int val, int val2, long mask)
139	{
140	union ds4424_raw_data raw;
141
142	if (val2 != 0)
143	return -EINVAL;
144
145	switch (mask) {
146	case IIO_CHAN_INFO_RAW:
147	if (val < S8_MIN \|\| val > S8_MAX)
148	return -EINVAL;
149
150	if (val > 0) {
151	raw.source_bit = DS4424_SOURCE_I;
152	raw.dx = val;
153	} else {
154	raw.source_bit = DS4424_SINK_I;
155	raw.dx = -val;
156	}
157
158	return ds4424_set_value(indio_dev, raw.bits, chan);
159
160	default:
161	return -EINVAL;
162	}
163	}
164
165	static int ds4424_verify_chip(struct iio_dev *indio_dev)
166	{
167	int ret, val;
168
169	ret = ds4424_get_value(indio_dev, &val, DS4424_DAC_ADDR(0));
170	if (ret < 0)
171	dev_err(&indio_dev->dev,
172	"%s failed. ret: %d\n", __func__, ret);
173
174	return ret;
175	}
176
177	static int __maybe_unused ds4424_suspend(struct device *dev)
178	{
179	struct i2c_client *client = to_i2c_client(dev);
180	struct iio_dev *indio_dev = i2c_get_clientdata(client);
181	struct ds4424_data *data = iio_priv(indio_dev);
182	int ret = 0;
183	int i;
184
185	for (i = 0; i < indio_dev->num_channels; i++) {
186	data->save[i] = data->raw[i];
187	ret = ds4424_set_value(indio_dev, 0,
188	&indio_dev->channels[i]);
189	if (ret < 0)
190	return ret;
191	}
192	return ret;
193	}
194
195	static int __maybe_unused ds4424_resume(struct device *dev)
196	{
197	struct i2c_client *client = to_i2c_client(dev);
198	struct iio_dev *indio_dev = i2c_get_clientdata(client);
199	struct ds4424_data *data = iio_priv(indio_dev);
200	int ret = 0;
201	int i;
202
203	for (i = 0; i < indio_dev->num_channels; i++) {
204	ret = ds4424_set_value(indio_dev, data->save[i],
205	&indio_dev->channels[i]);
206	if (ret < 0)
207	return ret;
208	}
209	return ret;
210	}
211
212	static SIMPLE_DEV_PM_OPS(ds4424_pm_ops, ds4424_suspend, ds4424_resume);
213
214	static const struct iio_info ds4424_info = {
215	.read_raw = ds4424_read_raw,
216	.write_raw = ds4424_write_raw,
217	};
218
219	static int ds4424_probe(struct i2c_client *client,
220	const struct i2c_device_id *id)
221	{
222	struct ds4424_data *data;
223	struct iio_dev *indio_dev;
224	int ret;
225
226	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
227	if (!indio_dev) {
228	dev_err(&client->dev, "iio dev alloc failed.\n");
229	return -ENOMEM;
230	}
231
232	data = iio_priv(indio_dev);
233	i2c_set_clientdata(client, indio_dev);
234	data->client = client;
235	indio_dev->name = id->name;
236	indio_dev->dev.of_node = client->dev.of_node;
237	indio_dev->dev.parent = &client->dev;
238
239	if (!client->dev.of_node) {
240	dev_err(&client->dev,
241	"Not found DT.\n");
242	return -ENODEV;
243	}
244
245	data->vcc_reg = devm_regulator_get(&client->dev, "vcc");
246	if (IS_ERR(data->vcc_reg)) {
247	dev_err(&client->dev,
248	"Failed to get vcc-supply regulator. err: %ld\n",
249	PTR_ERR(data->vcc_reg));
250	return PTR_ERR(data->vcc_reg);
251	}
252
253	mutex_init(&data->lock);
254	ret = regulator_enable(data->vcc_reg);
255	if (ret < 0) {
256	dev_err(&client->dev,
257	"Unable to enable the regulator.\n");
258	return ret;
259	}
260
261	usleep_range(1000, 1200);
262	ret = ds4424_verify_chip(indio_dev);
263	if (ret < 0)
264	goto fail;
265
266	switch (id->driver_data) {
267	case ID_DS4422:
268	indio_dev->num_channels = DS4422_MAX_DAC_CHANNELS;
269	break;
270	case ID_DS4424:
271	indio_dev->num_channels = DS4424_MAX_DAC_CHANNELS;
272	break;
273	default:
274	dev_err(&client->dev,
275	"ds4424: Invalid chip id.\n");
276	ret = -ENXIO;
277	goto fail;
278	}
279
280	indio_dev->channels = ds4424_channels;
281	indio_dev->modes = INDIO_DIRECT_MODE;
282	indio_dev->info = &ds4424_info;
283
284	ret = iio_device_register(indio_dev);
285	if (ret < 0) {
286	dev_err(&client->dev,
287	"iio_device_register failed. ret: %d\n", ret);
288	goto fail;
289	}
290
291	return ret;
292
293	fail:
294	regulator_disable(data->vcc_reg);
295	return ret;
296	}
297
298	static int ds4424_remove(struct i2c_client *client)
299	{
300	struct iio_dev *indio_dev = i2c_get_clientdata(client);
301	struct ds4424_data *data = iio_priv(indio_dev);
302
303	iio_device_unregister(indio_dev);
304	regulator_disable(data->vcc_reg);
305
306	return 0;
307	}
308
309	static const struct i2c_device_id ds4424_id[] = {
310	{ "ds4422", ID_DS4422 },
311	{ "ds4424", ID_DS4424 },
312	{ }
313	};
314
315	MODULE_DEVICE_TABLE(i2c, ds4424_id);
316
317	static const struct of_device_id ds4424_of_match[] = {
318	{ .compatible = "maxim,ds4422" },
319	{ .compatible = "maxim,ds4424" },
320	{ },
321	};
322
323	MODULE_DEVICE_TABLE(of, ds4424_of_match);
324
325	static struct i2c_driver ds4424_driver = {
326	.driver = {
327	.name = "ds4424",
328	.of_match_table = ds4424_of_match,
329	.pm = &ds4424_pm_ops,
330	},
331	.probe = ds4424_probe,
332	.remove = ds4424_remove,
333	.id_table = ds4424_id,
334	};
335	module_i2c_driver(ds4424_driver);
336
337	MODULE_DESCRIPTION("Maxim DS4424 DAC Driver");
338	MODULE_AUTHOR("Ismail H. Kose <[email protected]>");
339	MODULE_AUTHOR("Vishal Sood <[email protected]>");
340	MODULE_AUTHOR("David Jung <[email protected]>");
341	MODULE_LICENSE("GPL v2");