xref: /openbmc/linux/drivers/iio/dac/ad5446.c (revision d0e22329)
1 /*
2  * AD5446 SPI DAC driver
3  *
4  * Copyright 2010 Analog Devices Inc.
5  *
6  * Licensed under the GPL-2 or later.
7  */
8 
9 #include <linux/interrupt.h>
10 #include <linux/workqueue.h>
11 #include <linux/device.h>
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/sysfs.h>
15 #include <linux/list.h>
16 #include <linux/spi/spi.h>
17 #include <linux/i2c.h>
18 #include <linux/regulator/consumer.h>
19 #include <linux/err.h>
20 #include <linux/module.h>
21 
22 #include <linux/iio/iio.h>
23 #include <linux/iio/sysfs.h>
24 
25 #define MODE_PWRDWN_1k		0x1
26 #define MODE_PWRDWN_100k	0x2
27 #define MODE_PWRDWN_TRISTATE	0x3
28 
29 /**
30  * struct ad5446_state - driver instance specific data
31  * @spi:		spi_device
32  * @chip_info:		chip model specific constants, available modes etc
33  * @reg:		supply regulator
34  * @vref_mv:		actual reference voltage used
35  */
36 
37 struct ad5446_state {
38 	struct device		*dev;
39 	const struct ad5446_chip_info	*chip_info;
40 	struct regulator		*reg;
41 	unsigned short			vref_mv;
42 	unsigned			cached_val;
43 	unsigned			pwr_down_mode;
44 	unsigned			pwr_down;
45 };
46 
47 /**
48  * struct ad5446_chip_info - chip specific information
49  * @channel:		channel spec for the DAC
50  * @int_vref_mv:	AD5620/40/60: the internal reference voltage
51  * @write:		chip specific helper function to write to the register
52  */
53 
54 struct ad5446_chip_info {
55 	struct iio_chan_spec	channel;
56 	u16			int_vref_mv;
57 	int			(*write)(struct ad5446_state *st, unsigned val);
58 };
59 
60 static const char * const ad5446_powerdown_modes[] = {
61 	"1kohm_to_gnd", "100kohm_to_gnd", "three_state"
62 };
63 
64 static int ad5446_set_powerdown_mode(struct iio_dev *indio_dev,
65 	const struct iio_chan_spec *chan, unsigned int mode)
66 {
67 	struct ad5446_state *st = iio_priv(indio_dev);
68 
69 	st->pwr_down_mode = mode + 1;
70 
71 	return 0;
72 }
73 
74 static int ad5446_get_powerdown_mode(struct iio_dev *indio_dev,
75 	const struct iio_chan_spec *chan)
76 {
77 	struct ad5446_state *st = iio_priv(indio_dev);
78 
79 	return st->pwr_down_mode - 1;
80 }
81 
82 static const struct iio_enum ad5446_powerdown_mode_enum = {
83 	.items = ad5446_powerdown_modes,
84 	.num_items = ARRAY_SIZE(ad5446_powerdown_modes),
85 	.get = ad5446_get_powerdown_mode,
86 	.set = ad5446_set_powerdown_mode,
87 };
88 
89 static ssize_t ad5446_read_dac_powerdown(struct iio_dev *indio_dev,
90 					   uintptr_t private,
91 					   const struct iio_chan_spec *chan,
92 					   char *buf)
93 {
94 	struct ad5446_state *st = iio_priv(indio_dev);
95 
96 	return sprintf(buf, "%d\n", st->pwr_down);
97 }
98 
99 static ssize_t ad5446_write_dac_powerdown(struct iio_dev *indio_dev,
100 					    uintptr_t private,
101 					    const struct iio_chan_spec *chan,
102 					    const char *buf, size_t len)
103 {
104 	struct ad5446_state *st = iio_priv(indio_dev);
105 	unsigned int shift;
106 	unsigned int val;
107 	bool powerdown;
108 	int ret;
109 
110 	ret = strtobool(buf, &powerdown);
111 	if (ret)
112 		return ret;
113 
114 	mutex_lock(&indio_dev->mlock);
115 	st->pwr_down = powerdown;
116 
117 	if (st->pwr_down) {
118 		shift = chan->scan_type.realbits + chan->scan_type.shift;
119 		val = st->pwr_down_mode << shift;
120 	} else {
121 		val = st->cached_val;
122 	}
123 
124 	ret = st->chip_info->write(st, val);
125 	mutex_unlock(&indio_dev->mlock);
126 
127 	return ret ? ret : len;
128 }
129 
130 static const struct iio_chan_spec_ext_info ad5446_ext_info_powerdown[] = {
131 	{
132 		.name = "powerdown",
133 		.read = ad5446_read_dac_powerdown,
134 		.write = ad5446_write_dac_powerdown,
135 		.shared = IIO_SEPARATE,
136 	},
137 	IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5446_powerdown_mode_enum),
138 	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5446_powerdown_mode_enum),
139 	{ },
140 };
141 
142 #define _AD5446_CHANNEL(bits, storage, _shift, ext) { \
143 	.type = IIO_VOLTAGE, \
144 	.indexed = 1, \
145 	.output = 1, \
146 	.channel = 0, \
147 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
148 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
149 	.scan_type = { \
150 		.sign = 'u', \
151 		.realbits = (bits), \
152 		.storagebits = (storage), \
153 		.shift = (_shift), \
154 		}, \
155 	.ext_info = (ext), \
156 }
157 
158 #define AD5446_CHANNEL(bits, storage, shift) \
159 	_AD5446_CHANNEL(bits, storage, shift, NULL)
160 
161 #define AD5446_CHANNEL_POWERDOWN(bits, storage, shift) \
162 	_AD5446_CHANNEL(bits, storage, shift, ad5446_ext_info_powerdown)
163 
164 static int ad5446_read_raw(struct iio_dev *indio_dev,
165 			   struct iio_chan_spec const *chan,
166 			   int *val,
167 			   int *val2,
168 			   long m)
169 {
170 	struct ad5446_state *st = iio_priv(indio_dev);
171 
172 	switch (m) {
173 	case IIO_CHAN_INFO_RAW:
174 		*val = st->cached_val;
175 		return IIO_VAL_INT;
176 	case IIO_CHAN_INFO_SCALE:
177 		*val = st->vref_mv;
178 		*val2 = chan->scan_type.realbits;
179 		return IIO_VAL_FRACTIONAL_LOG2;
180 	}
181 	return -EINVAL;
182 }
183 
184 static int ad5446_write_raw(struct iio_dev *indio_dev,
185 			       struct iio_chan_spec const *chan,
186 			       int val,
187 			       int val2,
188 			       long mask)
189 {
190 	struct ad5446_state *st = iio_priv(indio_dev);
191 	int ret = 0;
192 
193 	switch (mask) {
194 	case IIO_CHAN_INFO_RAW:
195 		if (val >= (1 << chan->scan_type.realbits) || val < 0)
196 			return -EINVAL;
197 
198 		val <<= chan->scan_type.shift;
199 		mutex_lock(&indio_dev->mlock);
200 		st->cached_val = val;
201 		if (!st->pwr_down)
202 			ret = st->chip_info->write(st, val);
203 		mutex_unlock(&indio_dev->mlock);
204 		break;
205 	default:
206 		ret = -EINVAL;
207 	}
208 
209 	return ret;
210 }
211 
212 static const struct iio_info ad5446_info = {
213 	.read_raw = ad5446_read_raw,
214 	.write_raw = ad5446_write_raw,
215 };
216 
217 static int ad5446_probe(struct device *dev, const char *name,
218 			const struct ad5446_chip_info *chip_info)
219 {
220 	struct ad5446_state *st;
221 	struct iio_dev *indio_dev;
222 	struct regulator *reg;
223 	int ret, voltage_uv = 0;
224 
225 	reg = devm_regulator_get(dev, "vcc");
226 	if (!IS_ERR(reg)) {
227 		ret = regulator_enable(reg);
228 		if (ret)
229 			return ret;
230 
231 		ret = regulator_get_voltage(reg);
232 		if (ret < 0)
233 			goto error_disable_reg;
234 
235 		voltage_uv = ret;
236 	}
237 
238 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
239 	if (indio_dev == NULL) {
240 		ret = -ENOMEM;
241 		goto error_disable_reg;
242 	}
243 	st = iio_priv(indio_dev);
244 	st->chip_info = chip_info;
245 
246 	dev_set_drvdata(dev, indio_dev);
247 	st->reg = reg;
248 	st->dev = dev;
249 
250 	/* Establish that the iio_dev is a child of the device */
251 	indio_dev->dev.parent = dev;
252 	indio_dev->name = name;
253 	indio_dev->info = &ad5446_info;
254 	indio_dev->modes = INDIO_DIRECT_MODE;
255 	indio_dev->channels = &st->chip_info->channel;
256 	indio_dev->num_channels = 1;
257 
258 	st->pwr_down_mode = MODE_PWRDWN_1k;
259 
260 	if (st->chip_info->int_vref_mv)
261 		st->vref_mv = st->chip_info->int_vref_mv;
262 	else if (voltage_uv)
263 		st->vref_mv = voltage_uv / 1000;
264 	else
265 		dev_warn(dev, "reference voltage unspecified\n");
266 
267 	ret = iio_device_register(indio_dev);
268 	if (ret)
269 		goto error_disable_reg;
270 
271 	return 0;
272 
273 error_disable_reg:
274 	if (!IS_ERR(reg))
275 		regulator_disable(reg);
276 	return ret;
277 }
278 
279 static int ad5446_remove(struct device *dev)
280 {
281 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
282 	struct ad5446_state *st = iio_priv(indio_dev);
283 
284 	iio_device_unregister(indio_dev);
285 	if (!IS_ERR(st->reg))
286 		regulator_disable(st->reg);
287 
288 	return 0;
289 }
290 
291 #if IS_ENABLED(CONFIG_SPI_MASTER)
292 
293 static int ad5446_write(struct ad5446_state *st, unsigned val)
294 {
295 	struct spi_device *spi = to_spi_device(st->dev);
296 	__be16 data = cpu_to_be16(val);
297 
298 	return spi_write(spi, &data, sizeof(data));
299 }
300 
301 static int ad5660_write(struct ad5446_state *st, unsigned val)
302 {
303 	struct spi_device *spi = to_spi_device(st->dev);
304 	uint8_t data[3];
305 
306 	data[0] = (val >> 16) & 0xFF;
307 	data[1] = (val >> 8) & 0xFF;
308 	data[2] = val & 0xFF;
309 
310 	return spi_write(spi, data, sizeof(data));
311 }
312 
313 /**
314  * ad5446_supported_spi_device_ids:
315  * The AD5620/40/60 parts are available in different fixed internal reference
316  * voltage options. The actual part numbers may look differently
317  * (and a bit cryptic), however this style is used to make clear which
318  * parts are supported here.
319  */
320 enum ad5446_supported_spi_device_ids {
321 	ID_AD5300,
322 	ID_AD5310,
323 	ID_AD5320,
324 	ID_AD5444,
325 	ID_AD5446,
326 	ID_AD5450,
327 	ID_AD5451,
328 	ID_AD5541A,
329 	ID_AD5512A,
330 	ID_AD5553,
331 	ID_AD5601,
332 	ID_AD5611,
333 	ID_AD5621,
334 	ID_AD5641,
335 	ID_AD5620_2500,
336 	ID_AD5620_1250,
337 	ID_AD5640_2500,
338 	ID_AD5640_1250,
339 	ID_AD5660_2500,
340 	ID_AD5660_1250,
341 	ID_AD5662,
342 };
343 
344 static const struct ad5446_chip_info ad5446_spi_chip_info[] = {
345 	[ID_AD5300] = {
346 		.channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
347 		.write = ad5446_write,
348 	},
349 	[ID_AD5310] = {
350 		.channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
351 		.write = ad5446_write,
352 	},
353 	[ID_AD5320] = {
354 		.channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
355 		.write = ad5446_write,
356 	},
357 	[ID_AD5444] = {
358 		.channel = AD5446_CHANNEL(12, 16, 2),
359 		.write = ad5446_write,
360 	},
361 	[ID_AD5446] = {
362 		.channel = AD5446_CHANNEL(14, 16, 0),
363 		.write = ad5446_write,
364 	},
365 	[ID_AD5450] = {
366 		.channel = AD5446_CHANNEL(8, 16, 6),
367 		.write = ad5446_write,
368 	},
369 	[ID_AD5451] = {
370 		.channel = AD5446_CHANNEL(10, 16, 4),
371 		.write = ad5446_write,
372 	},
373 	[ID_AD5541A] = {
374 		.channel = AD5446_CHANNEL(16, 16, 0),
375 		.write = ad5446_write,
376 	},
377 	[ID_AD5512A] = {
378 		.channel = AD5446_CHANNEL(12, 16, 4),
379 		.write = ad5446_write,
380 	},
381 	[ID_AD5553] = {
382 		.channel = AD5446_CHANNEL(14, 16, 0),
383 		.write = ad5446_write,
384 	},
385 	[ID_AD5601] = {
386 		.channel = AD5446_CHANNEL_POWERDOWN(8, 16, 6),
387 		.write = ad5446_write,
388 	},
389 	[ID_AD5611] = {
390 		.channel = AD5446_CHANNEL_POWERDOWN(10, 16, 4),
391 		.write = ad5446_write,
392 	},
393 	[ID_AD5621] = {
394 		.channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
395 		.write = ad5446_write,
396 	},
397 	[ID_AD5641] = {
398 		.channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
399 		.write = ad5446_write,
400 	},
401 	[ID_AD5620_2500] = {
402 		.channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
403 		.int_vref_mv = 2500,
404 		.write = ad5446_write,
405 	},
406 	[ID_AD5620_1250] = {
407 		.channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
408 		.int_vref_mv = 1250,
409 		.write = ad5446_write,
410 	},
411 	[ID_AD5640_2500] = {
412 		.channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
413 		.int_vref_mv = 2500,
414 		.write = ad5446_write,
415 	},
416 	[ID_AD5640_1250] = {
417 		.channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
418 		.int_vref_mv = 1250,
419 		.write = ad5446_write,
420 	},
421 	[ID_AD5660_2500] = {
422 		.channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
423 		.int_vref_mv = 2500,
424 		.write = ad5660_write,
425 	},
426 	[ID_AD5660_1250] = {
427 		.channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
428 		.int_vref_mv = 1250,
429 		.write = ad5660_write,
430 	},
431 	[ID_AD5662] = {
432 		.channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
433 		.write = ad5660_write,
434 	},
435 };
436 
437 static const struct spi_device_id ad5446_spi_ids[] = {
438 	{"ad5300", ID_AD5300},
439 	{"ad5310", ID_AD5310},
440 	{"ad5320", ID_AD5320},
441 	{"ad5444", ID_AD5444},
442 	{"ad5446", ID_AD5446},
443 	{"ad5450", ID_AD5450},
444 	{"ad5451", ID_AD5451},
445 	{"ad5452", ID_AD5444}, /* ad5452 is compatible to the ad5444 */
446 	{"ad5453", ID_AD5446}, /* ad5453 is compatible to the ad5446 */
447 	{"ad5512a", ID_AD5512A},
448 	{"ad5541a", ID_AD5541A},
449 	{"ad5542a", ID_AD5541A}, /* ad5541a and ad5542a are compatible */
450 	{"ad5543", ID_AD5541A}, /* ad5541a and ad5543 are compatible */
451 	{"ad5553", ID_AD5553},
452 	{"ad5601", ID_AD5601},
453 	{"ad5611", ID_AD5611},
454 	{"ad5621", ID_AD5621},
455 	{"ad5641", ID_AD5641},
456 	{"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */
457 	{"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */
458 	{"ad5640-2500", ID_AD5640_2500},
459 	{"ad5640-1250", ID_AD5640_1250},
460 	{"ad5660-2500", ID_AD5660_2500},
461 	{"ad5660-1250", ID_AD5660_1250},
462 	{"ad5662", ID_AD5662},
463 	{"dac081s101", ID_AD5300}, /* compatible Texas Instruments chips */
464 	{"dac101s101", ID_AD5310},
465 	{"dac121s101", ID_AD5320},
466 	{"dac7512", ID_AD5320},
467 	{}
468 };
469 MODULE_DEVICE_TABLE(spi, ad5446_spi_ids);
470 
471 #ifdef CONFIG_OF
472 static const struct of_device_id ad5446_of_ids[] = {
473 	{ .compatible = "ti,dac7512" },
474 	{ }
475 };
476 MODULE_DEVICE_TABLE(of, ad5446_of_ids);
477 #endif
478 
479 static int ad5446_spi_probe(struct spi_device *spi)
480 {
481 	const struct spi_device_id *id = spi_get_device_id(spi);
482 
483 	return ad5446_probe(&spi->dev, id->name,
484 		&ad5446_spi_chip_info[id->driver_data]);
485 }
486 
487 static int ad5446_spi_remove(struct spi_device *spi)
488 {
489 	return ad5446_remove(&spi->dev);
490 }
491 
492 static struct spi_driver ad5446_spi_driver = {
493 	.driver = {
494 		.name	= "ad5446",
495 		.of_match_table = of_match_ptr(ad5446_of_ids),
496 	},
497 	.probe		= ad5446_spi_probe,
498 	.remove		= ad5446_spi_remove,
499 	.id_table	= ad5446_spi_ids,
500 };
501 
502 static int __init ad5446_spi_register_driver(void)
503 {
504 	return spi_register_driver(&ad5446_spi_driver);
505 }
506 
507 static void ad5446_spi_unregister_driver(void)
508 {
509 	spi_unregister_driver(&ad5446_spi_driver);
510 }
511 
512 #else
513 
514 static inline int ad5446_spi_register_driver(void) { return 0; }
515 static inline void ad5446_spi_unregister_driver(void) { }
516 
517 #endif
518 
519 #if IS_ENABLED(CONFIG_I2C)
520 
521 static int ad5622_write(struct ad5446_state *st, unsigned val)
522 {
523 	struct i2c_client *client = to_i2c_client(st->dev);
524 	__be16 data = cpu_to_be16(val);
525 
526 	return i2c_master_send(client, (char *)&data, sizeof(data));
527 }
528 
529 /**
530  * ad5446_supported_i2c_device_ids:
531  * The AD5620/40/60 parts are available in different fixed internal reference
532  * voltage options. The actual part numbers may look differently
533  * (and a bit cryptic), however this style is used to make clear which
534  * parts are supported here.
535  */
536 enum ad5446_supported_i2c_device_ids {
537 	ID_AD5602,
538 	ID_AD5612,
539 	ID_AD5622,
540 };
541 
542 static const struct ad5446_chip_info ad5446_i2c_chip_info[] = {
543 	[ID_AD5602] = {
544 		.channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
545 		.write = ad5622_write,
546 	},
547 	[ID_AD5612] = {
548 		.channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
549 		.write = ad5622_write,
550 	},
551 	[ID_AD5622] = {
552 		.channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
553 		.write = ad5622_write,
554 	},
555 };
556 
557 static int ad5446_i2c_probe(struct i2c_client *i2c,
558 			    const struct i2c_device_id *id)
559 {
560 	return ad5446_probe(&i2c->dev, id->name,
561 		&ad5446_i2c_chip_info[id->driver_data]);
562 }
563 
564 static int ad5446_i2c_remove(struct i2c_client *i2c)
565 {
566 	return ad5446_remove(&i2c->dev);
567 }
568 
569 static const struct i2c_device_id ad5446_i2c_ids[] = {
570 	{"ad5301", ID_AD5602},
571 	{"ad5311", ID_AD5612},
572 	{"ad5321", ID_AD5622},
573 	{"ad5602", ID_AD5602},
574 	{"ad5612", ID_AD5612},
575 	{"ad5622", ID_AD5622},
576 	{}
577 };
578 MODULE_DEVICE_TABLE(i2c, ad5446_i2c_ids);
579 
580 static struct i2c_driver ad5446_i2c_driver = {
581 	.driver = {
582 		   .name = "ad5446",
583 	},
584 	.probe = ad5446_i2c_probe,
585 	.remove = ad5446_i2c_remove,
586 	.id_table = ad5446_i2c_ids,
587 };
588 
589 static int __init ad5446_i2c_register_driver(void)
590 {
591 	return i2c_add_driver(&ad5446_i2c_driver);
592 }
593 
594 static void __exit ad5446_i2c_unregister_driver(void)
595 {
596 	i2c_del_driver(&ad5446_i2c_driver);
597 }
598 
599 #else
600 
601 static inline int ad5446_i2c_register_driver(void) { return 0; }
602 static inline void ad5446_i2c_unregister_driver(void) { }
603 
604 #endif
605 
606 static int __init ad5446_init(void)
607 {
608 	int ret;
609 
610 	ret = ad5446_spi_register_driver();
611 	if (ret)
612 		return ret;
613 
614 	ret = ad5446_i2c_register_driver();
615 	if (ret) {
616 		ad5446_spi_unregister_driver();
617 		return ret;
618 	}
619 
620 	return 0;
621 }
622 module_init(ad5446_init);
623 
624 static void __exit ad5446_exit(void)
625 {
626 	ad5446_i2c_unregister_driver();
627 	ad5446_spi_unregister_driver();
628 }
629 module_exit(ad5446_exit);
630 
631 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
632 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC");
633 MODULE_LICENSE("GPL v2");
634