xref: /linux/drivers/iio/dac/ad5446.c (revision cea0f76a483d1270ac6f6513964e3e75193dda48)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * AD5446 SPI DAC driver
4  *
5  * Copyright 2010 Analog Devices Inc.
6  */
7 
8 #include <linux/interrupt.h>
9 #include <linux/workqueue.h>
10 #include <linux/device.h>
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/sysfs.h>
14 #include <linux/list.h>
15 #include <linux/spi/spi.h>
16 #include <linux/i2c.h>
17 #include <linux/regulator/consumer.h>
18 #include <linux/err.h>
19 #include <linux/module.h>
20 
21 #include <linux/iio/iio.h>
22 #include <linux/iio/sysfs.h>
23 
24 #include <asm/unaligned.h>
25 
26 #define MODE_PWRDWN_1k		0x1
27 #define MODE_PWRDWN_100k	0x2
28 #define MODE_PWRDWN_TRISTATE	0x3
29 
30 /**
31  * struct ad5446_state - driver instance specific data
32  * @spi:		spi_device
33  * @chip_info:		chip model specific constants, available modes etc
34  * @reg:		supply regulator
35  * @vref_mv:		actual reference voltage used
36  * @lock		lock to protect the data buffer during write ops
37  */
38 
39 struct ad5446_state {
40 	struct device		*dev;
41 	const struct ad5446_chip_info	*chip_info;
42 	struct regulator		*reg;
43 	unsigned short			vref_mv;
44 	unsigned			cached_val;
45 	unsigned			pwr_down_mode;
46 	unsigned			pwr_down;
47 	struct mutex			lock;
48 };
49 
50 /**
51  * struct ad5446_chip_info - chip specific information
52  * @channel:		channel spec for the DAC
53  * @int_vref_mv:	AD5620/40/60: the internal reference voltage
54  * @write:		chip specific helper function to write to the register
55  */
56 
57 struct ad5446_chip_info {
58 	struct iio_chan_spec	channel;
59 	u16			int_vref_mv;
60 	int			(*write)(struct ad5446_state *st, unsigned val);
61 };
62 
63 static const char * const ad5446_powerdown_modes[] = {
64 	"1kohm_to_gnd", "100kohm_to_gnd", "three_state"
65 };
66 
67 static int ad5446_set_powerdown_mode(struct iio_dev *indio_dev,
68 	const struct iio_chan_spec *chan, unsigned int mode)
69 {
70 	struct ad5446_state *st = iio_priv(indio_dev);
71 
72 	st->pwr_down_mode = mode + 1;
73 
74 	return 0;
75 }
76 
77 static int ad5446_get_powerdown_mode(struct iio_dev *indio_dev,
78 	const struct iio_chan_spec *chan)
79 {
80 	struct ad5446_state *st = iio_priv(indio_dev);
81 
82 	return st->pwr_down_mode - 1;
83 }
84 
85 static const struct iio_enum ad5446_powerdown_mode_enum = {
86 	.items = ad5446_powerdown_modes,
87 	.num_items = ARRAY_SIZE(ad5446_powerdown_modes),
88 	.get = ad5446_get_powerdown_mode,
89 	.set = ad5446_set_powerdown_mode,
90 };
91 
92 static ssize_t ad5446_read_dac_powerdown(struct iio_dev *indio_dev,
93 					   uintptr_t private,
94 					   const struct iio_chan_spec *chan,
95 					   char *buf)
96 {
97 	struct ad5446_state *st = iio_priv(indio_dev);
98 
99 	return sprintf(buf, "%d\n", st->pwr_down);
100 }
101 
102 static ssize_t ad5446_write_dac_powerdown(struct iio_dev *indio_dev,
103 					    uintptr_t private,
104 					    const struct iio_chan_spec *chan,
105 					    const char *buf, size_t len)
106 {
107 	struct ad5446_state *st = iio_priv(indio_dev);
108 	unsigned int shift;
109 	unsigned int val;
110 	bool powerdown;
111 	int ret;
112 
113 	ret = strtobool(buf, &powerdown);
114 	if (ret)
115 		return ret;
116 
117 	mutex_lock(&st->lock);
118 	st->pwr_down = powerdown;
119 
120 	if (st->pwr_down) {
121 		shift = chan->scan_type.realbits + chan->scan_type.shift;
122 		val = st->pwr_down_mode << shift;
123 	} else {
124 		val = st->cached_val;
125 	}
126 
127 	ret = st->chip_info->write(st, val);
128 	mutex_unlock(&st->lock);
129 
130 	return ret ? ret : len;
131 }
132 
133 static const struct iio_chan_spec_ext_info ad5446_ext_info_powerdown[] = {
134 	{
135 		.name = "powerdown",
136 		.read = ad5446_read_dac_powerdown,
137 		.write = ad5446_write_dac_powerdown,
138 		.shared = IIO_SEPARATE,
139 	},
140 	IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5446_powerdown_mode_enum),
141 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5446_powerdown_mode_enum),
142 	{ },
143 };
144 
145 #define _AD5446_CHANNEL(bits, storage, _shift, ext) { \
146 	.type = IIO_VOLTAGE, \
147 	.indexed = 1, \
148 	.output = 1, \
149 	.channel = 0, \
150 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
151 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
152 	.scan_type = { \
153 		.sign = 'u', \
154 		.realbits = (bits), \
155 		.storagebits = (storage), \
156 		.shift = (_shift), \
157 		}, \
158 	.ext_info = (ext), \
159 }
160 
161 #define AD5446_CHANNEL(bits, storage, shift) \
162 	_AD5446_CHANNEL(bits, storage, shift, NULL)
163 
164 #define AD5446_CHANNEL_POWERDOWN(bits, storage, shift) \
165 	_AD5446_CHANNEL(bits, storage, shift, ad5446_ext_info_powerdown)
166 
167 static int ad5446_read_raw(struct iio_dev *indio_dev,
168 			   struct iio_chan_spec const *chan,
169 			   int *val,
170 			   int *val2,
171 			   long m)
172 {
173 	struct ad5446_state *st = iio_priv(indio_dev);
174 
175 	switch (m) {
176 	case IIO_CHAN_INFO_RAW:
177 		*val = st->cached_val;
178 		return IIO_VAL_INT;
179 	case IIO_CHAN_INFO_SCALE:
180 		*val = st->vref_mv;
181 		*val2 = chan->scan_type.realbits;
182 		return IIO_VAL_FRACTIONAL_LOG2;
183 	}
184 	return -EINVAL;
185 }
186 
187 static int ad5446_write_raw(struct iio_dev *indio_dev,
188 			       struct iio_chan_spec const *chan,
189 			       int val,
190 			       int val2,
191 			       long mask)
192 {
193 	struct ad5446_state *st = iio_priv(indio_dev);
194 	int ret = 0;
195 
196 	switch (mask) {
197 	case IIO_CHAN_INFO_RAW:
198 		if (val >= (1 << chan->scan_type.realbits) || val < 0)
199 			return -EINVAL;
200 
201 		val <<= chan->scan_type.shift;
202 		mutex_lock(&st->lock);
203 		st->cached_val = val;
204 		if (!st->pwr_down)
205 			ret = st->chip_info->write(st, val);
206 		mutex_unlock(&st->lock);
207 		break;
208 	default:
209 		ret = -EINVAL;
210 	}
211 
212 	return ret;
213 }
214 
215 static const struct iio_info ad5446_info = {
216 	.read_raw = ad5446_read_raw,
217 	.write_raw = ad5446_write_raw,
218 };
219 
220 static int ad5446_probe(struct device *dev, const char *name,
221 			const struct ad5446_chip_info *chip_info)
222 {
223 	struct ad5446_state *st;
224 	struct iio_dev *indio_dev;
225 	struct regulator *reg;
226 	int ret, voltage_uv = 0;
227 
228 	reg = devm_regulator_get(dev, "vcc");
229 	if (!IS_ERR(reg)) {
230 		ret = regulator_enable(reg);
231 		if (ret)
232 			return ret;
233 
234 		ret = regulator_get_voltage(reg);
235 		if (ret < 0)
236 			goto error_disable_reg;
237 
238 		voltage_uv = ret;
239 	}
240 
241 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
242 	if (indio_dev == NULL) {
243 		ret = -ENOMEM;
244 		goto error_disable_reg;
245 	}
246 	st = iio_priv(indio_dev);
247 	st->chip_info = chip_info;
248 
249 	dev_set_drvdata(dev, indio_dev);
250 	st->reg = reg;
251 	st->dev = dev;
252 
253 	/* Establish that the iio_dev is a child of the device */
254 	indio_dev->dev.parent = dev;
255 	indio_dev->name = name;
256 	indio_dev->info = &ad5446_info;
257 	indio_dev->modes = INDIO_DIRECT_MODE;
258 	indio_dev->channels = &st->chip_info->channel;
259 	indio_dev->num_channels = 1;
260 
261 	mutex_init(&st->lock);
262 
263 	st->pwr_down_mode = MODE_PWRDWN_1k;
264 
265 	if (st->chip_info->int_vref_mv)
266 		st->vref_mv = st->chip_info->int_vref_mv;
267 	else if (voltage_uv)
268 		st->vref_mv = voltage_uv / 1000;
269 	else
270 		dev_warn(dev, "reference voltage unspecified\n");
271 
272 	ret = iio_device_register(indio_dev);
273 	if (ret)
274 		goto error_disable_reg;
275 
276 	return 0;
277 
278 error_disable_reg:
279 	if (!IS_ERR(reg))
280 		regulator_disable(reg);
281 	return ret;
282 }
283 
284 static int ad5446_remove(struct device *dev)
285 {
286 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
287 	struct ad5446_state *st = iio_priv(indio_dev);
288 
289 	iio_device_unregister(indio_dev);
290 	if (!IS_ERR(st->reg))
291 		regulator_disable(st->reg);
292 
293 	return 0;
294 }
295 
296 #if IS_ENABLED(CONFIG_SPI_MASTER)
297 
298 static int ad5446_write(struct ad5446_state *st, unsigned val)
299 {
300 	struct spi_device *spi = to_spi_device(st->dev);
301 	__be16 data = cpu_to_be16(val);
302 
303 	return spi_write(spi, &data, sizeof(data));
304 }
305 
306 static int ad5660_write(struct ad5446_state *st, unsigned val)
307 {
308 	struct spi_device *spi = to_spi_device(st->dev);
309 	uint8_t data[3];
310 
311 	put_unaligned_be24(val, &data[0]);
312 
313 	return spi_write(spi, data, sizeof(data));
314 }
315 
316 /**
317  * ad5446_supported_spi_device_ids:
318  * The AD5620/40/60 parts are available in different fixed internal reference
319  * voltage options. The actual part numbers may look differently
320  * (and a bit cryptic), however this style is used to make clear which
321  * parts are supported here.
322  */
323 enum ad5446_supported_spi_device_ids {
324 	ID_AD5300,
325 	ID_AD5310,
326 	ID_AD5320,
327 	ID_AD5444,
328 	ID_AD5446,
329 	ID_AD5450,
330 	ID_AD5451,
331 	ID_AD5541A,
332 	ID_AD5512A,
333 	ID_AD5553,
334 	ID_AD5600,
335 	ID_AD5601,
336 	ID_AD5611,
337 	ID_AD5621,
338 	ID_AD5641,
339 	ID_AD5620_2500,
340 	ID_AD5620_1250,
341 	ID_AD5640_2500,
342 	ID_AD5640_1250,
343 	ID_AD5660_2500,
344 	ID_AD5660_1250,
345 	ID_AD5662,
346 };
347 
348 static const struct ad5446_chip_info ad5446_spi_chip_info[] = {
349 	[ID_AD5300] = {
350 		.channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
351 		.write = ad5446_write,
352 	},
353 	[ID_AD5310] = {
354 		.channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
355 		.write = ad5446_write,
356 	},
357 	[ID_AD5320] = {
358 		.channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
359 		.write = ad5446_write,
360 	},
361 	[ID_AD5444] = {
362 		.channel = AD5446_CHANNEL(12, 16, 2),
363 		.write = ad5446_write,
364 	},
365 	[ID_AD5446] = {
366 		.channel = AD5446_CHANNEL(14, 16, 0),
367 		.write = ad5446_write,
368 	},
369 	[ID_AD5450] = {
370 		.channel = AD5446_CHANNEL(8, 16, 6),
371 		.write = ad5446_write,
372 	},
373 	[ID_AD5451] = {
374 		.channel = AD5446_CHANNEL(10, 16, 4),
375 		.write = ad5446_write,
376 	},
377 	[ID_AD5541A] = {
378 		.channel = AD5446_CHANNEL(16, 16, 0),
379 		.write = ad5446_write,
380 	},
381 	[ID_AD5512A] = {
382 		.channel = AD5446_CHANNEL(12, 16, 4),
383 		.write = ad5446_write,
384 	},
385 	[ID_AD5553] = {
386 		.channel = AD5446_CHANNEL(14, 16, 0),
387 		.write = ad5446_write,
388 	},
389 	[ID_AD5600] = {
390 		.channel = AD5446_CHANNEL(16, 16, 0),
391 		.write = ad5446_write,
392 	},
393 	[ID_AD5601] = {
394 		.channel = AD5446_CHANNEL_POWERDOWN(8, 16, 6),
395 		.write = ad5446_write,
396 	},
397 	[ID_AD5611] = {
398 		.channel = AD5446_CHANNEL_POWERDOWN(10, 16, 4),
399 		.write = ad5446_write,
400 	},
401 	[ID_AD5621] = {
402 		.channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
403 		.write = ad5446_write,
404 	},
405 	[ID_AD5641] = {
406 		.channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
407 		.write = ad5446_write,
408 	},
409 	[ID_AD5620_2500] = {
410 		.channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
411 		.int_vref_mv = 2500,
412 		.write = ad5446_write,
413 	},
414 	[ID_AD5620_1250] = {
415 		.channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
416 		.int_vref_mv = 1250,
417 		.write = ad5446_write,
418 	},
419 	[ID_AD5640_2500] = {
420 		.channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
421 		.int_vref_mv = 2500,
422 		.write = ad5446_write,
423 	},
424 	[ID_AD5640_1250] = {
425 		.channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
426 		.int_vref_mv = 1250,
427 		.write = ad5446_write,
428 	},
429 	[ID_AD5660_2500] = {
430 		.channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
431 		.int_vref_mv = 2500,
432 		.write = ad5660_write,
433 	},
434 	[ID_AD5660_1250] = {
435 		.channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
436 		.int_vref_mv = 1250,
437 		.write = ad5660_write,
438 	},
439 	[ID_AD5662] = {
440 		.channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
441 		.write = ad5660_write,
442 	},
443 };
444 
445 static const struct spi_device_id ad5446_spi_ids[] = {
446 	{"ad5300", ID_AD5300},
447 	{"ad5310", ID_AD5310},
448 	{"ad5320", ID_AD5320},
449 	{"ad5444", ID_AD5444},
450 	{"ad5446", ID_AD5446},
451 	{"ad5450", ID_AD5450},
452 	{"ad5451", ID_AD5451},
453 	{"ad5452", ID_AD5444}, /* ad5452 is compatible to the ad5444 */
454 	{"ad5453", ID_AD5446}, /* ad5453 is compatible to the ad5446 */
455 	{"ad5512a", ID_AD5512A},
456 	{"ad5541a", ID_AD5541A},
457 	{"ad5542a", ID_AD5541A}, /* ad5541a and ad5542a are compatible */
458 	{"ad5543", ID_AD5541A}, /* ad5541a and ad5543 are compatible */
459 	{"ad5553", ID_AD5553},
460 	{"ad5600", ID_AD5600},
461 	{"ad5601", ID_AD5601},
462 	{"ad5611", ID_AD5611},
463 	{"ad5621", ID_AD5621},
464 	{"ad5641", ID_AD5641},
465 	{"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */
466 	{"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */
467 	{"ad5640-2500", ID_AD5640_2500},
468 	{"ad5640-1250", ID_AD5640_1250},
469 	{"ad5660-2500", ID_AD5660_2500},
470 	{"ad5660-1250", ID_AD5660_1250},
471 	{"ad5662", ID_AD5662},
472 	{"dac081s101", ID_AD5300}, /* compatible Texas Instruments chips */
473 	{"dac101s101", ID_AD5310},
474 	{"dac121s101", ID_AD5320},
475 	{"dac7512", ID_AD5320},
476 	{}
477 };
478 MODULE_DEVICE_TABLE(spi, ad5446_spi_ids);
479 
480 #ifdef CONFIG_OF
481 static const struct of_device_id ad5446_of_ids[] = {
482 	{ .compatible = "ti,dac7512" },
483 	{ }
484 };
485 MODULE_DEVICE_TABLE(of, ad5446_of_ids);
486 #endif
487 
488 static int ad5446_spi_probe(struct spi_device *spi)
489 {
490 	const struct spi_device_id *id = spi_get_device_id(spi);
491 
492 	return ad5446_probe(&spi->dev, id->name,
493 		&ad5446_spi_chip_info[id->driver_data]);
494 }
495 
496 static int ad5446_spi_remove(struct spi_device *spi)
497 {
498 	return ad5446_remove(&spi->dev);
499 }
500 
501 static struct spi_driver ad5446_spi_driver = {
502 	.driver = {
503 		.name	= "ad5446",
504 		.of_match_table = of_match_ptr(ad5446_of_ids),
505 	},
506 	.probe		= ad5446_spi_probe,
507 	.remove		= ad5446_spi_remove,
508 	.id_table	= ad5446_spi_ids,
509 };
510 
511 static int __init ad5446_spi_register_driver(void)
512 {
513 	return spi_register_driver(&ad5446_spi_driver);
514 }
515 
516 static void ad5446_spi_unregister_driver(void)
517 {
518 	spi_unregister_driver(&ad5446_spi_driver);
519 }
520 
521 #else
522 
523 static inline int ad5446_spi_register_driver(void) { return 0; }
524 static inline void ad5446_spi_unregister_driver(void) { }
525 
526 #endif
527 
528 #if IS_ENABLED(CONFIG_I2C)
529 
530 static int ad5622_write(struct ad5446_state *st, unsigned val)
531 {
532 	struct i2c_client *client = to_i2c_client(st->dev);
533 	__be16 data = cpu_to_be16(val);
534 
535 	return i2c_master_send(client, (char *)&data, sizeof(data));
536 }
537 
538 /**
539  * ad5446_supported_i2c_device_ids:
540  * The AD5620/40/60 parts are available in different fixed internal reference
541  * voltage options. The actual part numbers may look differently
542  * (and a bit cryptic), however this style is used to make clear which
543  * parts are supported here.
544  */
545 enum ad5446_supported_i2c_device_ids {
546 	ID_AD5602,
547 	ID_AD5612,
548 	ID_AD5622,
549 };
550 
551 static const struct ad5446_chip_info ad5446_i2c_chip_info[] = {
552 	[ID_AD5602] = {
553 		.channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
554 		.write = ad5622_write,
555 	},
556 	[ID_AD5612] = {
557 		.channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
558 		.write = ad5622_write,
559 	},
560 	[ID_AD5622] = {
561 		.channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
562 		.write = ad5622_write,
563 	},
564 };
565 
566 static int ad5446_i2c_probe(struct i2c_client *i2c,
567 			    const struct i2c_device_id *id)
568 {
569 	return ad5446_probe(&i2c->dev, id->name,
570 		&ad5446_i2c_chip_info[id->driver_data]);
571 }
572 
573 static int ad5446_i2c_remove(struct i2c_client *i2c)
574 {
575 	return ad5446_remove(&i2c->dev);
576 }
577 
578 static const struct i2c_device_id ad5446_i2c_ids[] = {
579 	{"ad5301", ID_AD5602},
580 	{"ad5311", ID_AD5612},
581 	{"ad5321", ID_AD5622},
582 	{"ad5602", ID_AD5602},
583 	{"ad5612", ID_AD5612},
584 	{"ad5622", ID_AD5622},
585 	{}
586 };
587 MODULE_DEVICE_TABLE(i2c, ad5446_i2c_ids);
588 
589 static struct i2c_driver ad5446_i2c_driver = {
590 	.driver = {
591 		   .name = "ad5446",
592 	},
593 	.probe = ad5446_i2c_probe,
594 	.remove = ad5446_i2c_remove,
595 	.id_table = ad5446_i2c_ids,
596 };
597 
598 static int __init ad5446_i2c_register_driver(void)
599 {
600 	return i2c_add_driver(&ad5446_i2c_driver);
601 }
602 
603 static void __exit ad5446_i2c_unregister_driver(void)
604 {
605 	i2c_del_driver(&ad5446_i2c_driver);
606 }
607 
608 #else
609 
610 static inline int ad5446_i2c_register_driver(void) { return 0; }
611 static inline void ad5446_i2c_unregister_driver(void) { }
612 
613 #endif
614 
615 static int __init ad5446_init(void)
616 {
617 	int ret;
618 
619 	ret = ad5446_spi_register_driver();
620 	if (ret)
621 		return ret;
622 
623 	ret = ad5446_i2c_register_driver();
624 	if (ret) {
625 		ad5446_spi_unregister_driver();
626 		return ret;
627 	}
628 
629 	return 0;
630 }
631 module_init(ad5446_init);
632 
633 static void __exit ad5446_exit(void)
634 {
635 	ad5446_i2c_unregister_driver();
636 	ad5446_spi_unregister_driver();
637 }
638 module_exit(ad5446_exit);
639 
640 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
641 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC");
642 MODULE_LICENSE("GPL v2");
643