summaryrefslogtreecommitdiff
path: root/drivers/iio/dac/ad5504.c
blob: 1e6449346b50868fadecda845b1f19af46a16c40 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
/*
 * AD5504, AD5501 High Voltage Digital to Analog Converter
 *
 * Copyright 2011 Analog Devices Inc.
 *
 * Licensed under the GPL-2.
 */

#include <linux/interrupt.h>
#include <linux/fs.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/spi/spi.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/regulator/consumer.h>
#include <linux/module.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/events.h>
#include <linux/iio/dac/ad5504.h>

#define AD5505_BITS			12
#define AD5504_RES_MASK			((1 << (AD5505_BITS)) - 1)

#define AD5504_CMD_READ			(1 << 15)
#define AD5504_CMD_WRITE		(0 << 15)
#define AD5504_ADDR(addr)		((addr) << 12)

/* Registers */
#define AD5504_ADDR_NOOP		0
#define AD5504_ADDR_DAC(x)		((x) + 1)
#define AD5504_ADDR_ALL_DAC		5
#define AD5504_ADDR_CTRL		7

/* Control Register */
#define AD5504_DAC_PWR(ch)		((ch) << 2)
#define AD5504_DAC_PWRDWN_MODE(mode)	((mode) << 6)
#define AD5504_DAC_PWRDN_20K		0
#define AD5504_DAC_PWRDN_3STATE		1

/**
 * struct ad5446_state - driver instance specific data
 * @us:			spi_device
 * @reg:		supply regulator
 * @vref_mv:		actual reference voltage used
 * @pwr_down_mask	power down mask
 * @pwr_down_mode	current power down mode
 * @data:		transfer buffer
 */
struct ad5504_state {
	struct spi_device		*spi;
	struct regulator		*reg;
	unsigned short			vref_mv;
	unsigned			pwr_down_mask;
	unsigned			pwr_down_mode;

	__be16				data[2] ____cacheline_aligned;
};

/**
 * ad5504_supported_device_ids:
 */

enum ad5504_supported_device_ids {
	ID_AD5504,
	ID_AD5501,
};

static int ad5504_spi_write(struct ad5504_state *st, u8 addr, u16 val)
{
	st->data[0] = cpu_to_be16(AD5504_CMD_WRITE | AD5504_ADDR(addr) |
			      (val & AD5504_RES_MASK));

	return spi_write(st->spi, &st->data[0], 2);
}

static int ad5504_spi_read(struct ad5504_state *st, u8 addr)
{
	int ret;
	struct spi_transfer t = {
	    .tx_buf = &st->data[0],
	    .rx_buf = &st->data[1],
	    .len = 2,
	};

	st->data[0] = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr));
	ret = spi_sync_transfer(st->spi, &t, 1);
	if (ret < 0)
		return ret;

	return be16_to_cpu(st->data[1]) & AD5504_RES_MASK;
}

static int ad5504_read_raw(struct iio_dev *indio_dev,
			   struct iio_chan_spec const *chan,
			   int *val,
			   int *val2,
			   long m)
{
	struct ad5504_state *st = iio_priv(indio_dev);
	int ret;

	switch (m) {
	case IIO_CHAN_INFO_RAW:
		ret = ad5504_spi_read(st, chan->address);
		if (ret < 0)
			return ret;

		*val = ret;

		return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
		*val = st->vref_mv;
		*val2 = chan->scan_type.realbits;
		return IIO_VAL_FRACTIONAL_LOG2;
	}
	return -EINVAL;
}

static int ad5504_write_raw(struct iio_dev *indio_dev,
			       struct iio_chan_spec const *chan,
			       int val,
			       int val2,
			       long mask)
{
	struct ad5504_state *st = iio_priv(indio_dev);
	int ret;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		if (val >= (1 << chan->scan_type.realbits) || val < 0)
			return -EINVAL;

		return ad5504_spi_write(st, chan->address, val);
	default:
		ret = -EINVAL;
	}

	return -EINVAL;
}

static const char * const ad5504_powerdown_modes[] = {
	"20kohm_to_gnd",
	"three_state",
};

static int ad5504_get_powerdown_mode(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan)
{
	struct ad5504_state *st = iio_priv(indio_dev);

	return st->pwr_down_mode;
}

static int ad5504_set_powerdown_mode(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, unsigned int mode)
{
	struct ad5504_state *st = iio_priv(indio_dev);

	st->pwr_down_mode = mode;

	return 0;
}

static const struct iio_enum ad5504_powerdown_mode_enum = {
	.items = ad5504_powerdown_modes,
	.num_items = ARRAY_SIZE(ad5504_powerdown_modes),
	.get = ad5504_get_powerdown_mode,
	.set = ad5504_set_powerdown_mode,
};

static ssize_t ad5504_read_dac_powerdown(struct iio_dev *indio_dev,
	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
{
	struct ad5504_state *st = iio_priv(indio_dev);

	return sprintf(buf, "%d\n",
			!(st->pwr_down_mask & (1 << chan->channel)));
}

static ssize_t ad5504_write_dac_powerdown(struct iio_dev *indio_dev,
	uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
	size_t len)
{
	bool pwr_down;
	int ret;
	struct ad5504_state *st = iio_priv(indio_dev);

	ret = strtobool(buf, &pwr_down);
	if (ret)
		return ret;

	if (pwr_down)
		st->pwr_down_mask |= (1 << chan->channel);
	else
		st->pwr_down_mask &= ~(1 << chan->channel);

	ret = ad5504_spi_write(st, AD5504_ADDR_CTRL,
				AD5504_DAC_PWRDWN_MODE(st->pwr_down_mode) |
				AD5504_DAC_PWR(st->pwr_down_mask));

	/* writes to the CTRL register must be followed by a NOOP */
	ad5504_spi_write(st, AD5504_ADDR_NOOP, 0);

	return ret ? ret : len;
}

static IIO_CONST_ATTR(temp0_thresh_rising_value, "110000");
static IIO_CONST_ATTR(temp0_thresh_rising_en, "1");

static struct attribute *ad5504_ev_attributes[] = {
	&iio_const_attr_temp0_thresh_rising_value.dev_attr.attr,
	&iio_const_attr_temp0_thresh_rising_en.dev_attr.attr,
	NULL,
};

static struct attribute_group ad5504_ev_attribute_group = {
	.attrs = ad5504_ev_attributes,
	.name = "events",
};

static irqreturn_t ad5504_event_handler(int irq, void *private)
{
	iio_push_event(private,
		       IIO_UNMOD_EVENT_CODE(IIO_TEMP,
					    0,
					    IIO_EV_TYPE_THRESH,
					    IIO_EV_DIR_RISING),
		       iio_get_time_ns());

	return IRQ_HANDLED;
}

static const struct iio_info ad5504_info = {
	.write_raw = ad5504_write_raw,
	.read_raw = ad5504_read_raw,
	.event_attrs = &ad5504_ev_attribute_group,
	.driver_module = THIS_MODULE,
};

static const struct iio_chan_spec_ext_info ad5504_ext_info[] = {
	{
		.name = "powerdown",
		.read = ad5504_read_dac_powerdown,
		.write = ad5504_write_dac_powerdown,
		.shared = IIO_SEPARATE,
	},
	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
		 &ad5504_powerdown_mode_enum),
	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5504_powerdown_mode_enum),
	{ },
};

#define AD5504_CHANNEL(_chan) { \
	.type = IIO_VOLTAGE, \
	.indexed = 1, \
	.output = 1, \
	.channel = (_chan), \
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
	.address = AD5504_ADDR_DAC(_chan), \
	.scan_type = { \
		.sign = 'u', \
		.realbits = 12, \
		.storagebits = 16, \
	}, \
	.ext_info = ad5504_ext_info, \
}

static const struct iio_chan_spec ad5504_channels[] = {
	AD5504_CHANNEL(0),
	AD5504_CHANNEL(1),
	AD5504_CHANNEL(2),
	AD5504_CHANNEL(3),
};

static int ad5504_probe(struct spi_device *spi)
{
	struct ad5504_platform_data *pdata = spi->dev.platform_data;
	struct iio_dev *indio_dev;
	struct ad5504_state *st;
	struct regulator *reg;
	int ret, voltage_uv = 0;

	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
	if (!indio_dev)
		return -ENOMEM;
	reg = devm_regulator_get(&spi->dev, "vcc");
	if (!IS_ERR(reg)) {
		ret = regulator_enable(reg);
		if (ret)
			return ret;

		ret = regulator_get_voltage(reg);
		if (ret < 0)
			goto error_disable_reg;

		voltage_uv = ret;
	}

	spi_set_drvdata(spi, indio_dev);
	st = iio_priv(indio_dev);
	if (voltage_uv)
		st->vref_mv = voltage_uv / 1000;
	else if (pdata)
		st->vref_mv = pdata->vref_mv;
	else
		dev_warn(&spi->dev, "reference voltage unspecified\n");

	st->reg = reg;
	st->spi = spi;
	indio_dev->dev.parent = &spi->dev;
	indio_dev->name = spi_get_device_id(st->spi)->name;
	indio_dev->info = &ad5504_info;
	if (spi_get_device_id(st->spi)->driver_data == ID_AD5501)
		indio_dev->num_channels = 1;
	else
		indio_dev->num_channels = 4;
	indio_dev->channels = ad5504_channels;
	indio_dev->modes = INDIO_DIRECT_MODE;

	if (spi->irq) {
		ret = devm_request_threaded_irq(&spi->dev, spi->irq,
					   NULL,
					   &ad5504_event_handler,
					   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
					   spi_get_device_id(st->spi)->name,
					   indio_dev);
		if (ret)
			goto error_disable_reg;
	}

	ret = iio_device_register(indio_dev);
	if (ret)
		goto error_disable_reg;

	return 0;

error_disable_reg:
	if (!IS_ERR(reg))
		regulator_disable(reg);

	return ret;
}

static int ad5504_remove(struct spi_device *spi)
{
	struct iio_dev *indio_dev = spi_get_drvdata(spi);
	struct ad5504_state *st = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);

	if (!IS_ERR(st->reg))
		regulator_disable(st->reg);

	return 0;
}

static const struct spi_device_id ad5504_id[] = {
	{"ad5504", ID_AD5504},
	{"ad5501", ID_AD5501},
	{}
};
MODULE_DEVICE_TABLE(spi, ad5504_id);

static struct spi_driver ad5504_driver = {
	.driver = {
		   .name = "ad5504",
		   .owner = THIS_MODULE,
		   },
	.probe = ad5504_probe,
	.remove = ad5504_remove,
	.id_table = ad5504_id,
};
module_spi_driver(ad5504_driver);

MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("Analog Devices AD5501/AD5501 DAC");
MODULE_LICENSE("GPL v2");