1/*
2 * Analog devices AD5380, AD5381, AD5382, AD5383, AD5390, AD5391, AD5392
3 * multi-channel Digital to Analog Converters driver
4 *
5 * Copyright 2011 Analog Devices Inc.
6 *
7 * Licensed under the GPL-2.
8 */
9
10#include <linux/device.h>
11#include <linux/err.h>
12#include <linux/i2c.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/spi/spi.h>
16#include <linux/slab.h>
17#include <linux/sysfs.h>
18#include <linux/regmap.h>
19#include <linux/regulator/consumer.h>
20
21#include <linux/iio/iio.h>
22#include <linux/iio/sysfs.h>
23
24#define AD5380_REG_DATA(x)	(((x) << 2) | 3)
25#define AD5380_REG_OFFSET(x)	(((x) << 2) | 2)
26#define AD5380_REG_GAIN(x)	(((x) << 2) | 1)
27#define AD5380_REG_SF_PWR_DOWN	(8 << 2)
28#define AD5380_REG_SF_PWR_UP	(9 << 2)
29#define AD5380_REG_SF_CTRL	(12 << 2)
30
31#define AD5380_CTRL_PWR_DOWN_MODE_OFFSET	13
32#define AD5380_CTRL_INT_VREF_2V5		BIT(12)
33#define AD5380_CTRL_INT_VREF_EN			BIT(10)
34
35/**
36 * struct ad5380_chip_info - chip specific information
37 * @channel_template:	channel specification template
38 * @num_channels:	number of channels
39 * @int_vref:		internal vref in uV
40*/
41
42struct ad5380_chip_info {
43	struct iio_chan_spec	channel_template;
44	unsigned int		num_channels;
45	unsigned int		int_vref;
46};
47
48/**
49 * struct ad5380_state - driver instance specific data
50 * @regmap:		regmap instance used by the device
51 * @chip_info:		chip model specific constants, available modes etc
52 * @vref_reg:		vref supply regulator
53 * @vref:		actual reference voltage used in uA
54 * @pwr_down:		whether the chip is currently in power down mode
55 */
56
57struct ad5380_state {
58	struct regmap			*regmap;
59	const struct ad5380_chip_info	*chip_info;
60	struct regulator		*vref_reg;
61	int				vref;
62	bool				pwr_down;
63};
64
65enum ad5380_type {
66	ID_AD5380_3,
67	ID_AD5380_5,
68	ID_AD5381_3,
69	ID_AD5381_5,
70	ID_AD5382_3,
71	ID_AD5382_5,
72	ID_AD5383_3,
73	ID_AD5383_5,
74	ID_AD5390_3,
75	ID_AD5390_5,
76	ID_AD5391_3,
77	ID_AD5391_5,
78	ID_AD5392_3,
79	ID_AD5392_5,
80};
81
82static ssize_t ad5380_read_dac_powerdown(struct iio_dev *indio_dev,
83	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
84{
85	struct ad5380_state *st = iio_priv(indio_dev);
86
87	return sprintf(buf, "%d\n", st->pwr_down);
88}
89
90static ssize_t ad5380_write_dac_powerdown(struct iio_dev *indio_dev,
91	 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
92	 size_t len)
93{
94	struct ad5380_state *st = iio_priv(indio_dev);
95	bool pwr_down;
96	int ret;
97
98	ret = strtobool(buf, &pwr_down);
99	if (ret)
100		return ret;
101
102	mutex_lock(&indio_dev->mlock);
103
104	if (pwr_down)
105		ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_DOWN, 0);
106	else
107		ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_UP, 0);
108
109	st->pwr_down = pwr_down;
110
111	mutex_unlock(&indio_dev->mlock);
112
113	return ret ? ret : len;
114}
115
116static const char * const ad5380_powerdown_modes[] = {
117	"100kohm_to_gnd",
118	"three_state",
119};
120
121static int ad5380_get_powerdown_mode(struct iio_dev *indio_dev,
122	const struct iio_chan_spec *chan)
123{
124	struct ad5380_state *st = iio_priv(indio_dev);
125	unsigned int mode;
126	int ret;
127
128	ret = regmap_read(st->regmap, AD5380_REG_SF_CTRL, &mode);
129	if (ret)
130		return ret;
131
132	mode = (mode >> AD5380_CTRL_PWR_DOWN_MODE_OFFSET) & 1;
133
134	return mode;
135}
136
137static int ad5380_set_powerdown_mode(struct iio_dev *indio_dev,
138	const struct iio_chan_spec *chan, unsigned int mode)
139{
140	struct ad5380_state *st = iio_priv(indio_dev);
141	int ret;
142
143	ret = regmap_update_bits(st->regmap, AD5380_REG_SF_CTRL,
144		1 << AD5380_CTRL_PWR_DOWN_MODE_OFFSET,
145		mode << AD5380_CTRL_PWR_DOWN_MODE_OFFSET);
146
147	return ret;
148}
149
150static const struct iio_enum ad5380_powerdown_mode_enum = {
151	.items = ad5380_powerdown_modes,
152	.num_items = ARRAY_SIZE(ad5380_powerdown_modes),
153	.get = ad5380_get_powerdown_mode,
154	.set = ad5380_set_powerdown_mode,
155};
156
157static unsigned int ad5380_info_to_reg(struct iio_chan_spec const *chan,
158	long info)
159{
160	switch (info) {
161	case 0:
162		return AD5380_REG_DATA(chan->address);
163	case IIO_CHAN_INFO_CALIBBIAS:
164		return AD5380_REG_OFFSET(chan->address);
165	case IIO_CHAN_INFO_CALIBSCALE:
166		return AD5380_REG_GAIN(chan->address);
167	default:
168		break;
169	}
170
171	return 0;
172}
173
174static int ad5380_write_raw(struct iio_dev *indio_dev,
175	struct iio_chan_spec const *chan, int val, int val2, long info)
176{
177	const unsigned int max_val = (1 << chan->scan_type.realbits);
178	struct ad5380_state *st = iio_priv(indio_dev);
179
180	switch (info) {
181	case IIO_CHAN_INFO_RAW:
182	case IIO_CHAN_INFO_CALIBSCALE:
183		if (val >= max_val || val < 0)
184			return -EINVAL;
185
186		return regmap_write(st->regmap,
187			ad5380_info_to_reg(chan, info),
188			val << chan->scan_type.shift);
189	case IIO_CHAN_INFO_CALIBBIAS:
190		val += (1 << chan->scan_type.realbits) / 2;
191		if (val >= max_val || val < 0)
192			return -EINVAL;
193
194		return regmap_write(st->regmap,
195			AD5380_REG_OFFSET(chan->address),
196			val << chan->scan_type.shift);
197	default:
198		break;
199	}
200	return -EINVAL;
201}
202
203static int ad5380_read_raw(struct iio_dev *indio_dev,
204	struct iio_chan_spec const *chan, int *val, int *val2, long info)
205{
206	struct ad5380_state *st = iio_priv(indio_dev);
207	int ret;
208
209	switch (info) {
210	case IIO_CHAN_INFO_RAW:
211	case IIO_CHAN_INFO_CALIBSCALE:
212		ret = regmap_read(st->regmap, ad5380_info_to_reg(chan, info),
213					val);
214		if (ret)
215			return ret;
216		*val >>= chan->scan_type.shift;
217		return IIO_VAL_INT;
218	case IIO_CHAN_INFO_CALIBBIAS:
219		ret = regmap_read(st->regmap, AD5380_REG_OFFSET(chan->address),
220					val);
221		if (ret)
222			return ret;
223		*val >>= chan->scan_type.shift;
224		val -= (1 << chan->scan_type.realbits) / 2;
225		return IIO_VAL_INT;
226	case IIO_CHAN_INFO_SCALE:
227		*val = 2 * st->vref;
228		*val2 = chan->scan_type.realbits;
229		return IIO_VAL_FRACTIONAL_LOG2;
230	default:
231		break;
232	}
233
234	return -EINVAL;
235}
236
237static const struct iio_info ad5380_info = {
238	.read_raw = ad5380_read_raw,
239	.write_raw = ad5380_write_raw,
240	.driver_module = THIS_MODULE,
241};
242
243static struct iio_chan_spec_ext_info ad5380_ext_info[] = {
244	{
245		.name = "powerdown",
246		.read = ad5380_read_dac_powerdown,
247		.write = ad5380_write_dac_powerdown,
248		.shared = IIO_SEPARATE,
249	},
250	IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
251		 &ad5380_powerdown_mode_enum),
252	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5380_powerdown_mode_enum),
253	{ },
254};
255
256#define AD5380_CHANNEL(_bits) {					\
257	.type = IIO_VOLTAGE,					\
258	.indexed = 1,						\
259	.output = 1,						\
260	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
261		BIT(IIO_CHAN_INFO_CALIBSCALE) |			\
262		BIT(IIO_CHAN_INFO_CALIBBIAS),			\
263	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
264	.scan_type = {						\
265		.sign = 'u',					\
266		.realbits = (_bits),				\
267		.storagebits =  16,				\
268		.shift = 14 - (_bits),				\
269	},							\
270	.ext_info = ad5380_ext_info,				\
271}
272
273static const struct ad5380_chip_info ad5380_chip_info_tbl[] = {
274	[ID_AD5380_3] = {
275		.channel_template = AD5380_CHANNEL(14),
276		.num_channels = 40,
277		.int_vref = 1250,
278	},
279	[ID_AD5380_5] = {
280		.channel_template = AD5380_CHANNEL(14),
281		.num_channels = 40,
282		.int_vref = 2500,
283	},
284	[ID_AD5381_3] = {
285		.channel_template = AD5380_CHANNEL(12),
286		.num_channels = 16,
287		.int_vref = 1250,
288	},
289	[ID_AD5381_5] = {
290		.channel_template = AD5380_CHANNEL(12),
291		.num_channels = 16,
292		.int_vref = 2500,
293	},
294	[ID_AD5382_3] = {
295		.channel_template = AD5380_CHANNEL(14),
296		.num_channels = 32,
297		.int_vref = 1250,
298	},
299	[ID_AD5382_5] = {
300		.channel_template = AD5380_CHANNEL(14),
301		.num_channels = 32,
302		.int_vref = 2500,
303	},
304	[ID_AD5383_3] = {
305		.channel_template = AD5380_CHANNEL(12),
306		.num_channels = 32,
307		.int_vref = 1250,
308	},
309	[ID_AD5383_5] = {
310		.channel_template = AD5380_CHANNEL(12),
311		.num_channels = 32,
312		.int_vref = 2500,
313	},
314	[ID_AD5390_3] = {
315		.channel_template = AD5380_CHANNEL(14),
316		.num_channels = 16,
317		.int_vref = 1250,
318	},
319	[ID_AD5390_5] = {
320		.channel_template = AD5380_CHANNEL(14),
321		.num_channels = 16,
322		.int_vref = 2500,
323	},
324	[ID_AD5391_3] = {
325		.channel_template = AD5380_CHANNEL(12),
326		.num_channels = 16,
327		.int_vref = 1250,
328	},
329	[ID_AD5391_5] = {
330		.channel_template = AD5380_CHANNEL(12),
331		.num_channels = 16,
332		.int_vref = 2500,
333	},
334	[ID_AD5392_3] = {
335		.channel_template = AD5380_CHANNEL(14),
336		.num_channels = 8,
337		.int_vref = 1250,
338	},
339	[ID_AD5392_5] = {
340		.channel_template = AD5380_CHANNEL(14),
341		.num_channels = 8,
342		.int_vref = 2500,
343	},
344};
345
346static int ad5380_alloc_channels(struct iio_dev *indio_dev)
347{
348	struct ad5380_state *st = iio_priv(indio_dev);
349	struct iio_chan_spec *channels;
350	unsigned int i;
351
352	channels = kcalloc(st->chip_info->num_channels,
353			   sizeof(struct iio_chan_spec), GFP_KERNEL);
354
355	if (!channels)
356		return -ENOMEM;
357
358	for (i = 0; i < st->chip_info->num_channels; ++i) {
359		channels[i] = st->chip_info->channel_template;
360		channels[i].channel = i;
361		channels[i].address = i;
362	}
363
364	indio_dev->channels = channels;
365
366	return 0;
367}
368
369static int ad5380_probe(struct device *dev, struct regmap *regmap,
370			enum ad5380_type type, const char *name)
371{
372	struct iio_dev *indio_dev;
373	struct ad5380_state *st;
374	unsigned int ctrl = 0;
375	int ret;
376
377	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
378	if (indio_dev == NULL) {
379		dev_err(dev, "Failed to allocate iio device\n");
380		return -ENOMEM;
381	}
382
383	st = iio_priv(indio_dev);
384	dev_set_drvdata(dev, indio_dev);
385
386	st->chip_info = &ad5380_chip_info_tbl[type];
387	st->regmap = regmap;
388
389	indio_dev->dev.parent = dev;
390	indio_dev->name = name;
391	indio_dev->info = &ad5380_info;
392	indio_dev->modes = INDIO_DIRECT_MODE;
393	indio_dev->num_channels = st->chip_info->num_channels;
394
395	ret = ad5380_alloc_channels(indio_dev);
396	if (ret) {
397		dev_err(dev, "Failed to allocate channel spec: %d\n", ret);
398		return ret;
399	}
400
401	if (st->chip_info->int_vref == 2500)
402		ctrl |= AD5380_CTRL_INT_VREF_2V5;
403
404	st->vref_reg = devm_regulator_get(dev, "vref");
405	if (!IS_ERR(st->vref_reg)) {
406		ret = regulator_enable(st->vref_reg);
407		if (ret) {
408			dev_err(dev, "Failed to enable vref regulators: %d\n",
409				ret);
410			goto error_free_reg;
411		}
412
413		ret = regulator_get_voltage(st->vref_reg);
414		if (ret < 0)
415			goto error_disable_reg;
416
417		st->vref = ret / 1000;
418	} else {
419		st->vref = st->chip_info->int_vref;
420		ctrl |= AD5380_CTRL_INT_VREF_EN;
421	}
422
423	ret = regmap_write(st->regmap, AD5380_REG_SF_CTRL, ctrl);
424	if (ret) {
425		dev_err(dev, "Failed to write to device: %d\n", ret);
426		goto error_disable_reg;
427	}
428
429	ret = iio_device_register(indio_dev);
430	if (ret) {
431		dev_err(dev, "Failed to register iio device: %d\n", ret);
432		goto error_disable_reg;
433	}
434
435	return 0;
436
437error_disable_reg:
438	if (!IS_ERR(st->vref_reg))
439		regulator_disable(st->vref_reg);
440error_free_reg:
441	kfree(indio_dev->channels);
442
443	return ret;
444}
445
446static int ad5380_remove(struct device *dev)
447{
448	struct iio_dev *indio_dev = dev_get_drvdata(dev);
449	struct ad5380_state *st = iio_priv(indio_dev);
450
451	iio_device_unregister(indio_dev);
452
453	kfree(indio_dev->channels);
454
455	if (!IS_ERR(st->vref_reg)) {
456		regulator_disable(st->vref_reg);
457	}
458
459	return 0;
460}
461
462static bool ad5380_reg_false(struct device *dev, unsigned int reg)
463{
464	return false;
465}
466
467static const struct regmap_config ad5380_regmap_config = {
468	.reg_bits = 10,
469	.val_bits = 14,
470
471	.max_register = AD5380_REG_DATA(40),
472	.cache_type = REGCACHE_RBTREE,
473
474	.volatile_reg = ad5380_reg_false,
475	.readable_reg = ad5380_reg_false,
476};
477
478#if IS_ENABLED(CONFIG_SPI_MASTER)
479
480static int ad5380_spi_probe(struct spi_device *spi)
481{
482	const struct spi_device_id *id = spi_get_device_id(spi);
483	struct regmap *regmap;
484
485	regmap = devm_regmap_init_spi(spi, &ad5380_regmap_config);
486
487	if (IS_ERR(regmap))
488		return PTR_ERR(regmap);
489
490	return ad5380_probe(&spi->dev, regmap, id->driver_data, id->name);
491}
492
493static int ad5380_spi_remove(struct spi_device *spi)
494{
495	return ad5380_remove(&spi->dev);
496}
497
498static const struct spi_device_id ad5380_spi_ids[] = {
499	{ "ad5380-3", ID_AD5380_3 },
500	{ "ad5380-5", ID_AD5380_5 },
501	{ "ad5381-3", ID_AD5381_3 },
502	{ "ad5381-5", ID_AD5381_5 },
503	{ "ad5382-3", ID_AD5382_3 },
504	{ "ad5382-5", ID_AD5382_5 },
505	{ "ad5383-3", ID_AD5383_3 },
506	{ "ad5383-5", ID_AD5383_5 },
507	{ "ad5384-3", ID_AD5380_3 },
508	{ "ad5384-5", ID_AD5380_5 },
509	{ "ad5390-3", ID_AD5390_3 },
510	{ "ad5390-5", ID_AD5390_5 },
511	{ "ad5391-3", ID_AD5391_3 },
512	{ "ad5391-5", ID_AD5391_5 },
513	{ "ad5392-3", ID_AD5392_3 },
514	{ "ad5392-5", ID_AD5392_5 },
515	{ }
516};
517MODULE_DEVICE_TABLE(spi, ad5380_spi_ids);
518
519static struct spi_driver ad5380_spi_driver = {
520	.driver = {
521		   .name = "ad5380",
522	},
523	.probe = ad5380_spi_probe,
524	.remove = ad5380_spi_remove,
525	.id_table = ad5380_spi_ids,
526};
527
528static inline int ad5380_spi_register_driver(void)
529{
530	return spi_register_driver(&ad5380_spi_driver);
531}
532
533static inline void ad5380_spi_unregister_driver(void)
534{
535	spi_unregister_driver(&ad5380_spi_driver);
536}
537
538#else
539
540static inline int ad5380_spi_register_driver(void)
541{
542	return 0;
543}
544
545static inline void ad5380_spi_unregister_driver(void)
546{
547}
548
549#endif
550
551#if IS_ENABLED(CONFIG_I2C)
552
553static int ad5380_i2c_probe(struct i2c_client *i2c,
554			    const struct i2c_device_id *id)
555{
556	struct regmap *regmap;
557
558	regmap = devm_regmap_init_i2c(i2c, &ad5380_regmap_config);
559
560	if (IS_ERR(regmap))
561		return PTR_ERR(regmap);
562
563	return ad5380_probe(&i2c->dev, regmap, id->driver_data, id->name);
564}
565
566static int ad5380_i2c_remove(struct i2c_client *i2c)
567{
568	return ad5380_remove(&i2c->dev);
569}
570
571static const struct i2c_device_id ad5380_i2c_ids[] = {
572	{ "ad5380-3", ID_AD5380_3 },
573	{ "ad5380-5", ID_AD5380_5 },
574	{ "ad5381-3", ID_AD5381_3 },
575	{ "ad5381-5", ID_AD5381_5 },
576	{ "ad5382-3", ID_AD5382_3 },
577	{ "ad5382-5", ID_AD5382_5 },
578	{ "ad5383-3", ID_AD5383_3 },
579	{ "ad5383-5", ID_AD5383_5 },
580	{ "ad5384-3", ID_AD5380_3 },
581	{ "ad5384-5", ID_AD5380_5 },
582	{ "ad5390-3", ID_AD5390_3 },
583	{ "ad5390-5", ID_AD5390_5 },
584	{ "ad5391-3", ID_AD5391_3 },
585	{ "ad5391-5", ID_AD5391_5 },
586	{ "ad5392-3", ID_AD5392_3 },
587	{ "ad5392-5", ID_AD5392_5 },
588	{ }
589};
590MODULE_DEVICE_TABLE(i2c, ad5380_i2c_ids);
591
592static struct i2c_driver ad5380_i2c_driver = {
593	.driver = {
594		   .name = "ad5380",
595	},
596	.probe = ad5380_i2c_probe,
597	.remove = ad5380_i2c_remove,
598	.id_table = ad5380_i2c_ids,
599};
600
601static inline int ad5380_i2c_register_driver(void)
602{
603	return i2c_add_driver(&ad5380_i2c_driver);
604}
605
606static inline void ad5380_i2c_unregister_driver(void)
607{
608	i2c_del_driver(&ad5380_i2c_driver);
609}
610
611#else
612
613static inline int ad5380_i2c_register_driver(void)
614{
615	return 0;
616}
617
618static inline void ad5380_i2c_unregister_driver(void)
619{
620}
621
622#endif
623
624static int __init ad5380_spi_init(void)
625{
626	int ret;
627
628	ret = ad5380_spi_register_driver();
629	if (ret)
630		return ret;
631
632	ret = ad5380_i2c_register_driver();
633	if (ret) {
634		ad5380_spi_unregister_driver();
635		return ret;
636	}
637
638	return 0;
639}
640module_init(ad5380_spi_init);
641
642static void __exit ad5380_spi_exit(void)
643{
644	ad5380_i2c_unregister_driver();
645	ad5380_spi_unregister_driver();
646
647}
648module_exit(ad5380_spi_exit);
649
650MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
651MODULE_DESCRIPTION("Analog Devices AD5380/81/82/83/84/90/91/92 DAC");
652MODULE_LICENSE("GPL v2");
653