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
ad5446_set_powerdown_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int mode)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
ad5446_get_powerdown_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)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
ad5446_read_dac_powerdown(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,char * buf)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
ad5446_write_dac_powerdown(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)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 },
136 IIO_ENUM("powerdown_mode", false, &ad5446_powerdown_mode_enum),
137 IIO_ENUM_AVAILABLE("powerdown_mode", &ad5446_powerdown_mode_enum),
138 { },
139 };
140
141 #define _AD5446_CHANNEL(bits, storage, shift, ext) { \
142 .type = IIO_VOLTAGE, \
143 .indexed = 1, \
144 .output = 1, \
145 .channel = 0, \
146 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
147 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
148 .scan_type = IIO_ST('u', (bits), (storage), (shift)), \
149 .ext_info = (ext), \
150 }
151
152 #define AD5446_CHANNEL(bits, storage, shift) \
153 _AD5446_CHANNEL(bits, storage, shift, NULL)
154
155 #define AD5446_CHANNEL_POWERDOWN(bits, storage, shift) \
156 _AD5446_CHANNEL(bits, storage, shift, ad5446_ext_info_powerdown)
157
ad5446_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long m)158 static int ad5446_read_raw(struct iio_dev *indio_dev,
159 struct iio_chan_spec const *chan,
160 int *val,
161 int *val2,
162 long m)
163 {
164 struct ad5446_state *st = iio_priv(indio_dev);
165 unsigned long scale_uv;
166
167 switch (m) {
168 case IIO_CHAN_INFO_RAW:
169 *val = st->cached_val;
170 return IIO_VAL_INT;
171 case IIO_CHAN_INFO_SCALE:
172 scale_uv = (st->vref_mv * 1000) >> chan->scan_type.realbits;
173 *val = scale_uv / 1000;
174 *val2 = (scale_uv % 1000) * 1000;
175 return IIO_VAL_INT_PLUS_MICRO;
176
177 }
178 return -EINVAL;
179 }
180
ad5446_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)181 static int ad5446_write_raw(struct iio_dev *indio_dev,
182 struct iio_chan_spec const *chan,
183 int val,
184 int val2,
185 long mask)
186 {
187 struct ad5446_state *st = iio_priv(indio_dev);
188 int ret = 0;
189
190 switch (mask) {
191 case IIO_CHAN_INFO_RAW:
192 if (val >= (1 << chan->scan_type.realbits) || val < 0)
193 return -EINVAL;
194
195 val <<= chan->scan_type.shift;
196 mutex_lock(&indio_dev->mlock);
197 st->cached_val = val;
198 if (!st->pwr_down)
199 ret = st->chip_info->write(st, val);
200 mutex_unlock(&indio_dev->mlock);
201 break;
202 default:
203 ret = -EINVAL;
204 }
205
206 return ret;
207 }
208
209 static const struct iio_info ad5446_info = {
210 .read_raw = ad5446_read_raw,
211 .write_raw = ad5446_write_raw,
212 .driver_module = THIS_MODULE,
213 };
214
ad5446_probe(struct device * dev,const char * name,const struct ad5446_chip_info * chip_info)215 static int ad5446_probe(struct device *dev, const char *name,
216 const struct ad5446_chip_info *chip_info)
217 {
218 struct ad5446_state *st;
219 struct iio_dev *indio_dev;
220 struct regulator *reg;
221 int ret, voltage_uv = 0;
222
223 reg = regulator_get(dev, "vcc");
224 if (!IS_ERR(reg)) {
225 ret = regulator_enable(reg);
226 if (ret)
227 goto error_put_reg;
228
229 ret = regulator_get_voltage(reg);
230 if (ret < 0)
231 goto error_disable_reg;
232
233 voltage_uv = ret;
234 }
235
236 indio_dev = iio_device_alloc(sizeof(*st));
237 if (indio_dev == NULL) {
238 ret = -ENOMEM;
239 goto error_disable_reg;
240 }
241 st = iio_priv(indio_dev);
242 st->chip_info = chip_info;
243
244 dev_set_drvdata(dev, indio_dev);
245 st->reg = reg;
246 st->dev = dev;
247
248 /* Establish that the iio_dev is a child of the device */
249 indio_dev->dev.parent = dev;
250 indio_dev->name = name;
251 indio_dev->info = &ad5446_info;
252 indio_dev->modes = INDIO_DIRECT_MODE;
253 indio_dev->channels = &st->chip_info->channel;
254 indio_dev->num_channels = 1;
255
256 st->pwr_down_mode = MODE_PWRDWN_1k;
257
258 if (st->chip_info->int_vref_mv)
259 st->vref_mv = st->chip_info->int_vref_mv;
260 else if (voltage_uv)
261 st->vref_mv = voltage_uv / 1000;
262 else
263 dev_warn(dev, "reference voltage unspecified\n");
264
265 ret = iio_device_register(indio_dev);
266 if (ret)
267 goto error_free_device;
268
269 return 0;
270
271 error_free_device:
272 iio_device_free(indio_dev);
273 error_disable_reg:
274 if (!IS_ERR(reg))
275 regulator_disable(reg);
276 error_put_reg:
277 if (!IS_ERR(reg))
278 regulator_put(reg);
279
280 return ret;
281 }
282
ad5446_remove(struct device * dev)283 static int ad5446_remove(struct device *dev)
284 {
285 struct iio_dev *indio_dev = dev_get_drvdata(dev);
286 struct ad5446_state *st = iio_priv(indio_dev);
287
288 iio_device_unregister(indio_dev);
289 if (!IS_ERR(st->reg)) {
290 regulator_disable(st->reg);
291 regulator_put(st->reg);
292 }
293 iio_device_free(indio_dev);
294
295 return 0;
296 }
297
298 #if IS_ENABLED(CONFIG_SPI_MASTER)
299
ad5446_write(struct ad5446_state * st,unsigned val)300 static int ad5446_write(struct ad5446_state *st, unsigned val)
301 {
302 struct spi_device *spi = to_spi_device(st->dev);
303 __be16 data = cpu_to_be16(val);
304
305 return spi_write(spi, &data, sizeof(data));
306 }
307
ad5660_write(struct ad5446_state * st,unsigned val)308 static int ad5660_write(struct ad5446_state *st, unsigned val)
309 {
310 struct spi_device *spi = to_spi_device(st->dev);
311 uint8_t data[3];
312
313 data[0] = (val >> 16) & 0xFF;
314 data[1] = (val >> 8) & 0xFF;
315 data[2] = val & 0xFF;
316
317 return spi_write(spi, data, sizeof(data));
318 }
319
320 /**
321 * ad5446_supported_spi_device_ids:
322 * The AD5620/40/60 parts are available in different fixed internal reference
323 * voltage options. The actual part numbers may look differently
324 * (and a bit cryptic), however this style is used to make clear which
325 * parts are supported here.
326 */
327 enum ad5446_supported_spi_device_ids {
328 ID_AD5300,
329 ID_AD5310,
330 ID_AD5320,
331 ID_AD5444,
332 ID_AD5446,
333 ID_AD5450,
334 ID_AD5451,
335 ID_AD5541A,
336 ID_AD5512A,
337 ID_AD5553,
338 ID_AD5601,
339 ID_AD5611,
340 ID_AD5621,
341 ID_AD5620_2500,
342 ID_AD5620_1250,
343 ID_AD5640_2500,
344 ID_AD5640_1250,
345 ID_AD5660_2500,
346 ID_AD5660_1250,
347 ID_AD5662,
348 };
349
350 static const struct ad5446_chip_info ad5446_spi_chip_info[] = {
351 [ID_AD5300] = {
352 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
353 .write = ad5446_write,
354 },
355 [ID_AD5310] = {
356 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
357 .write = ad5446_write,
358 },
359 [ID_AD5320] = {
360 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
361 .write = ad5446_write,
362 },
363 [ID_AD5444] = {
364 .channel = AD5446_CHANNEL(12, 16, 2),
365 .write = ad5446_write,
366 },
367 [ID_AD5446] = {
368 .channel = AD5446_CHANNEL(14, 16, 0),
369 .write = ad5446_write,
370 },
371 [ID_AD5450] = {
372 .channel = AD5446_CHANNEL(8, 16, 6),
373 .write = ad5446_write,
374 },
375 [ID_AD5451] = {
376 .channel = AD5446_CHANNEL(10, 16, 4),
377 .write = ad5446_write,
378 },
379 [ID_AD5541A] = {
380 .channel = AD5446_CHANNEL(16, 16, 0),
381 .write = ad5446_write,
382 },
383 [ID_AD5512A] = {
384 .channel = AD5446_CHANNEL(12, 16, 4),
385 .write = ad5446_write,
386 },
387 [ID_AD5553] = {
388 .channel = AD5446_CHANNEL(14, 16, 0),
389 .write = ad5446_write,
390 },
391 [ID_AD5601] = {
392 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 6),
393 .write = ad5446_write,
394 },
395 [ID_AD5611] = {
396 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 4),
397 .write = ad5446_write,
398 },
399 [ID_AD5621] = {
400 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
401 .write = ad5446_write,
402 },
403 [ID_AD5620_2500] = {
404 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
405 .int_vref_mv = 2500,
406 .write = ad5446_write,
407 },
408 [ID_AD5620_1250] = {
409 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
410 .int_vref_mv = 1250,
411 .write = ad5446_write,
412 },
413 [ID_AD5640_2500] = {
414 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
415 .int_vref_mv = 2500,
416 .write = ad5446_write,
417 },
418 [ID_AD5640_1250] = {
419 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
420 .int_vref_mv = 1250,
421 .write = ad5446_write,
422 },
423 [ID_AD5660_2500] = {
424 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
425 .int_vref_mv = 2500,
426 .write = ad5660_write,
427 },
428 [ID_AD5660_1250] = {
429 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
430 .int_vref_mv = 1250,
431 .write = ad5660_write,
432 },
433 [ID_AD5662] = {
434 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
435 .write = ad5660_write,
436 },
437 };
438
439 static const struct spi_device_id ad5446_spi_ids[] = {
440 {"ad5300", ID_AD5300},
441 {"ad5310", ID_AD5310},
442 {"ad5320", ID_AD5320},
443 {"ad5444", ID_AD5444},
444 {"ad5446", ID_AD5446},
445 {"ad5450", ID_AD5450},
446 {"ad5451", ID_AD5451},
447 {"ad5452", ID_AD5444}, /* ad5452 is compatible to the ad5444 */
448 {"ad5453", ID_AD5446}, /* ad5453 is compatible to the ad5446 */
449 {"ad5512a", ID_AD5512A},
450 {"ad5541a", ID_AD5541A},
451 {"ad5542a", ID_AD5541A}, /* ad5541a and ad5542a are compatible */
452 {"ad5543", ID_AD5541A}, /* ad5541a and ad5543 are compatible */
453 {"ad5553", ID_AD5553},
454 {"ad5601", ID_AD5601},
455 {"ad5611", ID_AD5611},
456 {"ad5621", ID_AD5621},
457 {"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */
458 {"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */
459 {"ad5640-2500", ID_AD5640_2500},
460 {"ad5640-1250", ID_AD5640_1250},
461 {"ad5660-2500", ID_AD5660_2500},
462 {"ad5660-1250", ID_AD5660_1250},
463 {"ad5662", ID_AD5662},
464 {}
465 };
466 MODULE_DEVICE_TABLE(spi, ad5446_spi_ids);
467
ad5446_spi_probe(struct spi_device * spi)468 static int ad5446_spi_probe(struct spi_device *spi)
469 {
470 const struct spi_device_id *id = spi_get_device_id(spi);
471
472 return ad5446_probe(&spi->dev, id->name,
473 &ad5446_spi_chip_info[id->driver_data]);
474 }
475
ad5446_spi_remove(struct spi_device * spi)476 static int ad5446_spi_remove(struct spi_device *spi)
477 {
478 return ad5446_remove(&spi->dev);
479 }
480
481 static struct spi_driver ad5446_spi_driver = {
482 .driver = {
483 .name = "ad5446",
484 .owner = THIS_MODULE,
485 },
486 .probe = ad5446_spi_probe,
487 .remove = ad5446_spi_remove,
488 .id_table = ad5446_spi_ids,
489 };
490
ad5446_spi_register_driver(void)491 static int __init ad5446_spi_register_driver(void)
492 {
493 return spi_register_driver(&ad5446_spi_driver);
494 }
495
ad5446_spi_unregister_driver(void)496 static void ad5446_spi_unregister_driver(void)
497 {
498 spi_unregister_driver(&ad5446_spi_driver);
499 }
500
501 #else
502
ad5446_spi_register_driver(void)503 static inline int ad5446_spi_register_driver(void) { return 0; }
ad5446_spi_unregister_driver(void)504 static inline void ad5446_spi_unregister_driver(void) { }
505
506 #endif
507
508 #if IS_ENABLED(CONFIG_I2C)
509
ad5622_write(struct ad5446_state * st,unsigned val)510 static int ad5622_write(struct ad5446_state *st, unsigned val)
511 {
512 struct i2c_client *client = to_i2c_client(st->dev);
513 __be16 data = cpu_to_be16(val);
514
515 return i2c_master_send(client, (char *)&data, sizeof(data));
516 }
517
518 /**
519 * ad5446_supported_i2c_device_ids:
520 * The AD5620/40/60 parts are available in different fixed internal reference
521 * voltage options. The actual part numbers may look differently
522 * (and a bit cryptic), however this style is used to make clear which
523 * parts are supported here.
524 */
525 enum ad5446_supported_i2c_device_ids {
526 ID_AD5602,
527 ID_AD5612,
528 ID_AD5622,
529 };
530
531 static const struct ad5446_chip_info ad5446_i2c_chip_info[] = {
532 [ID_AD5602] = {
533 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
534 .write = ad5622_write,
535 },
536 [ID_AD5612] = {
537 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
538 .write = ad5622_write,
539 },
540 [ID_AD5622] = {
541 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
542 .write = ad5622_write,
543 },
544 };
545
ad5446_i2c_probe(struct i2c_client * i2c,const struct i2c_device_id * id)546 static int ad5446_i2c_probe(struct i2c_client *i2c,
547 const struct i2c_device_id *id)
548 {
549 return ad5446_probe(&i2c->dev, id->name,
550 &ad5446_i2c_chip_info[id->driver_data]);
551 }
552
ad5446_i2c_remove(struct i2c_client * i2c)553 static int ad5446_i2c_remove(struct i2c_client *i2c)
554 {
555 return ad5446_remove(&i2c->dev);
556 }
557
558 static const struct i2c_device_id ad5446_i2c_ids[] = {
559 {"ad5301", ID_AD5602},
560 {"ad5311", ID_AD5612},
561 {"ad5321", ID_AD5622},
562 {"ad5602", ID_AD5602},
563 {"ad5612", ID_AD5612},
564 {"ad5622", ID_AD5622},
565 {}
566 };
567 MODULE_DEVICE_TABLE(i2c, ad5446_i2c_ids);
568
569 static struct i2c_driver ad5446_i2c_driver = {
570 .driver = {
571 .name = "ad5446",
572 .owner = THIS_MODULE,
573 },
574 .probe = ad5446_i2c_probe,
575 .remove = ad5446_i2c_remove,
576 .id_table = ad5446_i2c_ids,
577 };
578
ad5446_i2c_register_driver(void)579 static int __init ad5446_i2c_register_driver(void)
580 {
581 return i2c_add_driver(&ad5446_i2c_driver);
582 }
583
ad5446_i2c_unregister_driver(void)584 static void __exit ad5446_i2c_unregister_driver(void)
585 {
586 i2c_del_driver(&ad5446_i2c_driver);
587 }
588
589 #else
590
ad5446_i2c_register_driver(void)591 static inline int ad5446_i2c_register_driver(void) { return 0; }
ad5446_i2c_unregister_driver(void)592 static inline void ad5446_i2c_unregister_driver(void) { }
593
594 #endif
595
ad5446_init(void)596 static int __init ad5446_init(void)
597 {
598 int ret;
599
600 ret = ad5446_spi_register_driver();
601 if (ret)
602 return ret;
603
604 ret = ad5446_i2c_register_driver();
605 if (ret) {
606 ad5446_spi_unregister_driver();
607 return ret;
608 }
609
610 return 0;
611 }
612 module_init(ad5446_init);
613
ad5446_exit(void)614 static void __exit ad5446_exit(void)
615 {
616 ad5446_i2c_unregister_driver();
617 ad5446_spi_unregister_driver();
618 }
619 module_exit(ad5446_exit);
620
621 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
622 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC");
623 MODULE_LICENSE("GPL v2");
624