Linux 4.19.133
[linux/fpc-iii.git] / drivers / iio / dac / ad5592r-base.c
blob095530c233e412242e83c55bb3085a643c2ba77f
1 /*
2 * AD5592R Digital <-> Analog converters driver
4 * Copyright 2014-2016 Analog Devices Inc.
5 * Author: Paul Cercueil <paul.cercueil@analog.com>
7 * Licensed under the GPL-2.
8 */
10 #include <linux/bitops.h>
11 #include <linux/delay.h>
12 #include <linux/iio/iio.h>
13 #include <linux/module.h>
14 #include <linux/mutex.h>
15 #include <linux/of.h>
16 #include <linux/regulator/consumer.h>
17 #include <linux/gpio/consumer.h>
18 #include <linux/gpio/driver.h>
19 #include <linux/gpio.h>
20 #include <linux/property.h>
22 #include <dt-bindings/iio/adi,ad5592r.h>
24 #include "ad5592r-base.h"
26 static int ad5592r_gpio_get(struct gpio_chip *chip, unsigned offset)
28 struct ad5592r_state *st = gpiochip_get_data(chip);
29 int ret = 0;
30 u8 val;
32 mutex_lock(&st->gpio_lock);
34 if (st->gpio_out & BIT(offset))
35 val = st->gpio_val;
36 else
37 ret = st->ops->gpio_read(st, &val);
39 mutex_unlock(&st->gpio_lock);
41 if (ret < 0)
42 return ret;
44 return !!(val & BIT(offset));
47 static void ad5592r_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
49 struct ad5592r_state *st = gpiochip_get_data(chip);
51 mutex_lock(&st->gpio_lock);
53 if (value)
54 st->gpio_val |= BIT(offset);
55 else
56 st->gpio_val &= ~BIT(offset);
58 st->ops->reg_write(st, AD5592R_REG_GPIO_SET, st->gpio_val);
60 mutex_unlock(&st->gpio_lock);
63 static int ad5592r_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
65 struct ad5592r_state *st = gpiochip_get_data(chip);
66 int ret;
68 mutex_lock(&st->gpio_lock);
70 st->gpio_out &= ~BIT(offset);
71 st->gpio_in |= BIT(offset);
73 ret = st->ops->reg_write(st, AD5592R_REG_GPIO_OUT_EN, st->gpio_out);
74 if (ret < 0)
75 goto err_unlock;
77 ret = st->ops->reg_write(st, AD5592R_REG_GPIO_IN_EN, st->gpio_in);
79 err_unlock:
80 mutex_unlock(&st->gpio_lock);
82 return ret;
85 static int ad5592r_gpio_direction_output(struct gpio_chip *chip,
86 unsigned offset, int value)
88 struct ad5592r_state *st = gpiochip_get_data(chip);
89 int ret;
91 mutex_lock(&st->gpio_lock);
93 if (value)
94 st->gpio_val |= BIT(offset);
95 else
96 st->gpio_val &= ~BIT(offset);
98 st->gpio_in &= ~BIT(offset);
99 st->gpio_out |= BIT(offset);
101 ret = st->ops->reg_write(st, AD5592R_REG_GPIO_SET, st->gpio_val);
102 if (ret < 0)
103 goto err_unlock;
105 ret = st->ops->reg_write(st, AD5592R_REG_GPIO_OUT_EN, st->gpio_out);
106 if (ret < 0)
107 goto err_unlock;
109 ret = st->ops->reg_write(st, AD5592R_REG_GPIO_IN_EN, st->gpio_in);
111 err_unlock:
112 mutex_unlock(&st->gpio_lock);
114 return ret;
117 static int ad5592r_gpio_request(struct gpio_chip *chip, unsigned offset)
119 struct ad5592r_state *st = gpiochip_get_data(chip);
121 if (!(st->gpio_map & BIT(offset))) {
122 dev_err(st->dev, "GPIO %d is reserved by alternate function\n",
123 offset);
124 return -ENODEV;
127 return 0;
130 static int ad5592r_gpio_init(struct ad5592r_state *st)
132 if (!st->gpio_map)
133 return 0;
135 st->gpiochip.label = dev_name(st->dev);
136 st->gpiochip.base = -1;
137 st->gpiochip.ngpio = 8;
138 st->gpiochip.parent = st->dev;
139 st->gpiochip.can_sleep = true;
140 st->gpiochip.direction_input = ad5592r_gpio_direction_input;
141 st->gpiochip.direction_output = ad5592r_gpio_direction_output;
142 st->gpiochip.get = ad5592r_gpio_get;
143 st->gpiochip.set = ad5592r_gpio_set;
144 st->gpiochip.request = ad5592r_gpio_request;
145 st->gpiochip.owner = THIS_MODULE;
147 mutex_init(&st->gpio_lock);
149 return gpiochip_add_data(&st->gpiochip, st);
152 static void ad5592r_gpio_cleanup(struct ad5592r_state *st)
154 if (st->gpio_map)
155 gpiochip_remove(&st->gpiochip);
158 static int ad5592r_reset(struct ad5592r_state *st)
160 struct gpio_desc *gpio;
161 struct iio_dev *iio_dev = iio_priv_to_dev(st);
163 gpio = devm_gpiod_get_optional(st->dev, "reset", GPIOD_OUT_LOW);
164 if (IS_ERR(gpio))
165 return PTR_ERR(gpio);
167 if (gpio) {
168 udelay(1);
169 gpiod_set_value(gpio, 1);
170 } else {
171 mutex_lock(&iio_dev->mlock);
172 /* Writing this magic value resets the device */
173 st->ops->reg_write(st, AD5592R_REG_RESET, 0xdac);
174 mutex_unlock(&iio_dev->mlock);
177 udelay(250);
179 return 0;
182 static int ad5592r_get_vref(struct ad5592r_state *st)
184 int ret;
186 if (st->reg) {
187 ret = regulator_get_voltage(st->reg);
188 if (ret < 0)
189 return ret;
191 return ret / 1000;
192 } else {
193 return 2500;
197 static int ad5592r_set_channel_modes(struct ad5592r_state *st)
199 const struct ad5592r_rw_ops *ops = st->ops;
200 int ret;
201 unsigned i;
202 struct iio_dev *iio_dev = iio_priv_to_dev(st);
203 u8 pulldown = 0, tristate = 0, dac = 0, adc = 0;
204 u16 read_back;
206 for (i = 0; i < st->num_channels; i++) {
207 switch (st->channel_modes[i]) {
208 case CH_MODE_DAC:
209 dac |= BIT(i);
210 break;
212 case CH_MODE_ADC:
213 adc |= BIT(i);
214 break;
216 case CH_MODE_DAC_AND_ADC:
217 dac |= BIT(i);
218 adc |= BIT(i);
219 break;
221 case CH_MODE_GPIO:
222 st->gpio_map |= BIT(i);
223 st->gpio_in |= BIT(i); /* Default to input */
224 break;
226 case CH_MODE_UNUSED:
227 /* fall-through */
228 default:
229 switch (st->channel_offstate[i]) {
230 case CH_OFFSTATE_OUT_TRISTATE:
231 tristate |= BIT(i);
232 break;
234 case CH_OFFSTATE_OUT_LOW:
235 st->gpio_out |= BIT(i);
236 break;
238 case CH_OFFSTATE_OUT_HIGH:
239 st->gpio_out |= BIT(i);
240 st->gpio_val |= BIT(i);
241 break;
243 case CH_OFFSTATE_PULLDOWN:
244 /* fall-through */
245 default:
246 pulldown |= BIT(i);
247 break;
252 mutex_lock(&iio_dev->mlock);
254 /* Pull down unused pins to GND */
255 ret = ops->reg_write(st, AD5592R_REG_PULLDOWN, pulldown);
256 if (ret)
257 goto err_unlock;
259 ret = ops->reg_write(st, AD5592R_REG_TRISTATE, tristate);
260 if (ret)
261 goto err_unlock;
263 /* Configure pins that we use */
264 ret = ops->reg_write(st, AD5592R_REG_DAC_EN, dac);
265 if (ret)
266 goto err_unlock;
268 ret = ops->reg_write(st, AD5592R_REG_ADC_EN, adc);
269 if (ret)
270 goto err_unlock;
272 ret = ops->reg_write(st, AD5592R_REG_GPIO_SET, st->gpio_val);
273 if (ret)
274 goto err_unlock;
276 ret = ops->reg_write(st, AD5592R_REG_GPIO_OUT_EN, st->gpio_out);
277 if (ret)
278 goto err_unlock;
280 ret = ops->reg_write(st, AD5592R_REG_GPIO_IN_EN, st->gpio_in);
281 if (ret)
282 goto err_unlock;
284 /* Verify that we can read back at least one register */
285 ret = ops->reg_read(st, AD5592R_REG_ADC_EN, &read_back);
286 if (!ret && (read_back & 0xff) != adc)
287 ret = -EIO;
289 err_unlock:
290 mutex_unlock(&iio_dev->mlock);
291 return ret;
294 static int ad5592r_reset_channel_modes(struct ad5592r_state *st)
296 int i;
298 for (i = 0; i < ARRAY_SIZE(st->channel_modes); i++)
299 st->channel_modes[i] = CH_MODE_UNUSED;
301 return ad5592r_set_channel_modes(st);
304 static int ad5592r_write_raw(struct iio_dev *iio_dev,
305 struct iio_chan_spec const *chan, int val, int val2, long mask)
307 struct ad5592r_state *st = iio_priv(iio_dev);
308 int ret;
310 switch (mask) {
311 case IIO_CHAN_INFO_RAW:
313 if (val >= (1 << chan->scan_type.realbits) || val < 0)
314 return -EINVAL;
316 if (!chan->output)
317 return -EINVAL;
319 mutex_lock(&iio_dev->mlock);
320 ret = st->ops->write_dac(st, chan->channel, val);
321 if (!ret)
322 st->cached_dac[chan->channel] = val;
323 mutex_unlock(&iio_dev->mlock);
324 return ret;
325 case IIO_CHAN_INFO_SCALE:
326 if (chan->type == IIO_VOLTAGE) {
327 bool gain;
329 if (val == st->scale_avail[0][0] &&
330 val2 == st->scale_avail[0][1])
331 gain = false;
332 else if (val == st->scale_avail[1][0] &&
333 val2 == st->scale_avail[1][1])
334 gain = true;
335 else
336 return -EINVAL;
338 mutex_lock(&iio_dev->mlock);
340 ret = st->ops->reg_read(st, AD5592R_REG_CTRL,
341 &st->cached_gp_ctrl);
342 if (ret < 0) {
343 mutex_unlock(&iio_dev->mlock);
344 return ret;
347 if (chan->output) {
348 if (gain)
349 st->cached_gp_ctrl |=
350 AD5592R_REG_CTRL_DAC_RANGE;
351 else
352 st->cached_gp_ctrl &=
353 ~AD5592R_REG_CTRL_DAC_RANGE;
354 } else {
355 if (gain)
356 st->cached_gp_ctrl |=
357 AD5592R_REG_CTRL_ADC_RANGE;
358 else
359 st->cached_gp_ctrl &=
360 ~AD5592R_REG_CTRL_ADC_RANGE;
363 ret = st->ops->reg_write(st, AD5592R_REG_CTRL,
364 st->cached_gp_ctrl);
365 mutex_unlock(&iio_dev->mlock);
367 return ret;
369 break;
370 default:
371 return -EINVAL;
374 return 0;
377 static int ad5592r_read_raw(struct iio_dev *iio_dev,
378 struct iio_chan_spec const *chan,
379 int *val, int *val2, long m)
381 struct ad5592r_state *st = iio_priv(iio_dev);
382 u16 read_val;
383 int ret;
385 switch (m) {
386 case IIO_CHAN_INFO_RAW:
387 mutex_lock(&iio_dev->mlock);
389 if (!chan->output) {
390 ret = st->ops->read_adc(st, chan->channel, &read_val);
391 if (ret)
392 goto unlock;
394 if ((read_val >> 12 & 0x7) != (chan->channel & 0x7)) {
395 dev_err(st->dev, "Error while reading channel %u\n",
396 chan->channel);
397 ret = -EIO;
398 goto unlock;
401 read_val &= GENMASK(11, 0);
403 } else {
404 read_val = st->cached_dac[chan->channel];
407 dev_dbg(st->dev, "Channel %u read: 0x%04hX\n",
408 chan->channel, read_val);
410 *val = (int) read_val;
411 ret = IIO_VAL_INT;
412 break;
413 case IIO_CHAN_INFO_SCALE:
414 *val = ad5592r_get_vref(st);
416 if (chan->type == IIO_TEMP) {
417 s64 tmp = *val * (3767897513LL / 25LL);
418 *val = div_s64_rem(tmp, 1000000000LL, val2);
420 ret = IIO_VAL_INT_PLUS_MICRO;
421 } else {
422 int mult;
424 mutex_lock(&iio_dev->mlock);
426 if (chan->output)
427 mult = !!(st->cached_gp_ctrl &
428 AD5592R_REG_CTRL_DAC_RANGE);
429 else
430 mult = !!(st->cached_gp_ctrl &
431 AD5592R_REG_CTRL_ADC_RANGE);
433 *val *= ++mult;
435 *val2 = chan->scan_type.realbits;
436 ret = IIO_VAL_FRACTIONAL_LOG2;
438 break;
439 case IIO_CHAN_INFO_OFFSET:
440 ret = ad5592r_get_vref(st);
442 mutex_lock(&iio_dev->mlock);
444 if (st->cached_gp_ctrl & AD5592R_REG_CTRL_ADC_RANGE)
445 *val = (-34365 * 25) / ret;
446 else
447 *val = (-75365 * 25) / ret;
448 ret = IIO_VAL_INT;
449 break;
450 default:
451 ret = -EINVAL;
454 unlock:
455 mutex_unlock(&iio_dev->mlock);
456 return ret;
459 static int ad5592r_write_raw_get_fmt(struct iio_dev *indio_dev,
460 struct iio_chan_spec const *chan, long mask)
462 switch (mask) {
463 case IIO_CHAN_INFO_SCALE:
464 return IIO_VAL_INT_PLUS_NANO;
466 default:
467 return IIO_VAL_INT_PLUS_MICRO;
470 return -EINVAL;
473 static const struct iio_info ad5592r_info = {
474 .read_raw = ad5592r_read_raw,
475 .write_raw = ad5592r_write_raw,
476 .write_raw_get_fmt = ad5592r_write_raw_get_fmt,
479 static ssize_t ad5592r_show_scale_available(struct iio_dev *iio_dev,
480 uintptr_t private,
481 const struct iio_chan_spec *chan,
482 char *buf)
484 struct ad5592r_state *st = iio_priv(iio_dev);
486 return sprintf(buf, "%d.%09u %d.%09u\n",
487 st->scale_avail[0][0], st->scale_avail[0][1],
488 st->scale_avail[1][0], st->scale_avail[1][1]);
491 static struct iio_chan_spec_ext_info ad5592r_ext_info[] = {
493 .name = "scale_available",
494 .read = ad5592r_show_scale_available,
495 .shared = true,
500 static void ad5592r_setup_channel(struct iio_dev *iio_dev,
501 struct iio_chan_spec *chan, bool output, unsigned id)
503 chan->type = IIO_VOLTAGE;
504 chan->indexed = 1;
505 chan->output = output;
506 chan->channel = id;
507 chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
508 chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
509 chan->scan_type.sign = 'u';
510 chan->scan_type.realbits = 12;
511 chan->scan_type.storagebits = 16;
512 chan->ext_info = ad5592r_ext_info;
515 static int ad5592r_alloc_channels(struct ad5592r_state *st)
517 unsigned i, curr_channel = 0,
518 num_channels = st->num_channels;
519 struct iio_dev *iio_dev = iio_priv_to_dev(st);
520 struct iio_chan_spec *channels;
521 struct fwnode_handle *child;
522 u32 reg, tmp;
523 int ret;
525 device_for_each_child_node(st->dev, child) {
526 ret = fwnode_property_read_u32(child, "reg", &reg);
527 if (ret || reg >= ARRAY_SIZE(st->channel_modes))
528 continue;
530 ret = fwnode_property_read_u32(child, "adi,mode", &tmp);
531 if (!ret)
532 st->channel_modes[reg] = tmp;
534 fwnode_property_read_u32(child, "adi,off-state", &tmp);
535 if (!ret)
536 st->channel_offstate[reg] = tmp;
539 channels = devm_kcalloc(st->dev,
540 1 + 2 * num_channels, sizeof(*channels),
541 GFP_KERNEL);
542 if (!channels)
543 return -ENOMEM;
545 for (i = 0; i < num_channels; i++) {
546 switch (st->channel_modes[i]) {
547 case CH_MODE_DAC:
548 ad5592r_setup_channel(iio_dev, &channels[curr_channel],
549 true, i);
550 curr_channel++;
551 break;
553 case CH_MODE_ADC:
554 ad5592r_setup_channel(iio_dev, &channels[curr_channel],
555 false, i);
556 curr_channel++;
557 break;
559 case CH_MODE_DAC_AND_ADC:
560 ad5592r_setup_channel(iio_dev, &channels[curr_channel],
561 true, i);
562 curr_channel++;
563 ad5592r_setup_channel(iio_dev, &channels[curr_channel],
564 false, i);
565 curr_channel++;
566 break;
568 default:
569 continue;
573 channels[curr_channel].type = IIO_TEMP;
574 channels[curr_channel].channel = 8;
575 channels[curr_channel].info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
576 BIT(IIO_CHAN_INFO_SCALE) |
577 BIT(IIO_CHAN_INFO_OFFSET);
578 curr_channel++;
580 iio_dev->num_channels = curr_channel;
581 iio_dev->channels = channels;
583 return 0;
586 static void ad5592r_init_scales(struct ad5592r_state *st, int vref_mV)
588 s64 tmp = (s64)vref_mV * 1000000000LL >> 12;
590 st->scale_avail[0][0] =
591 div_s64_rem(tmp, 1000000000LL, &st->scale_avail[0][1]);
592 st->scale_avail[1][0] =
593 div_s64_rem(tmp * 2, 1000000000LL, &st->scale_avail[1][1]);
596 int ad5592r_probe(struct device *dev, const char *name,
597 const struct ad5592r_rw_ops *ops)
599 struct iio_dev *iio_dev;
600 struct ad5592r_state *st;
601 int ret;
603 iio_dev = devm_iio_device_alloc(dev, sizeof(*st));
604 if (!iio_dev)
605 return -ENOMEM;
607 st = iio_priv(iio_dev);
608 st->dev = dev;
609 st->ops = ops;
610 st->num_channels = 8;
611 dev_set_drvdata(dev, iio_dev);
613 st->reg = devm_regulator_get_optional(dev, "vref");
614 if (IS_ERR(st->reg)) {
615 if ((PTR_ERR(st->reg) != -ENODEV) && dev->of_node)
616 return PTR_ERR(st->reg);
618 st->reg = NULL;
619 } else {
620 ret = regulator_enable(st->reg);
621 if (ret)
622 return ret;
625 iio_dev->dev.parent = dev;
626 iio_dev->name = name;
627 iio_dev->info = &ad5592r_info;
628 iio_dev->modes = INDIO_DIRECT_MODE;
630 ad5592r_init_scales(st, ad5592r_get_vref(st));
632 ret = ad5592r_reset(st);
633 if (ret)
634 goto error_disable_reg;
636 ret = ops->reg_write(st, AD5592R_REG_PD,
637 (st->reg == NULL) ? AD5592R_REG_PD_EN_REF : 0);
638 if (ret)
639 goto error_disable_reg;
641 ret = ad5592r_alloc_channels(st);
642 if (ret)
643 goto error_disable_reg;
645 ret = ad5592r_set_channel_modes(st);
646 if (ret)
647 goto error_reset_ch_modes;
649 ret = iio_device_register(iio_dev);
650 if (ret)
651 goto error_reset_ch_modes;
653 ret = ad5592r_gpio_init(st);
654 if (ret)
655 goto error_dev_unregister;
657 return 0;
659 error_dev_unregister:
660 iio_device_unregister(iio_dev);
662 error_reset_ch_modes:
663 ad5592r_reset_channel_modes(st);
665 error_disable_reg:
666 if (st->reg)
667 regulator_disable(st->reg);
669 return ret;
671 EXPORT_SYMBOL_GPL(ad5592r_probe);
673 int ad5592r_remove(struct device *dev)
675 struct iio_dev *iio_dev = dev_get_drvdata(dev);
676 struct ad5592r_state *st = iio_priv(iio_dev);
678 iio_device_unregister(iio_dev);
679 ad5592r_reset_channel_modes(st);
680 ad5592r_gpio_cleanup(st);
682 if (st->reg)
683 regulator_disable(st->reg);
685 return 0;
687 EXPORT_SYMBOL_GPL(ad5592r_remove);
689 MODULE_AUTHOR("Paul Cercueil <paul.cercueil@analog.com>");
690 MODULE_DESCRIPTION("Analog Devices AD5592R multi-channel converters");
691 MODULE_LICENSE("GPL v2");