2 * AD7606 SPI ADC driver
4 * Copyright 2011 Analog Devices Inc.
6 * Licensed under the GPL-2.
9 #include <linux/interrupt.h>
10 #include <linux/device.h>
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/sysfs.h>
14 #include <linux/regulator/consumer.h>
15 #include <linux/err.h>
16 #include <linux/gpio.h>
17 #include <linux/delay.h>
18 #include <linux/sched.h>
19 #include <linux/module.h>
21 #include <linux/iio/iio.h>
22 #include <linux/iio/sysfs.h>
23 #include <linux/iio/buffer.h>
27 int ad7606_reset(struct ad7606_state *st)
29 if (gpio_is_valid(st->pdata->gpio_reset)) {
30 gpio_set_value(st->pdata->gpio_reset, 1);
31 ndelay(100); /* t_reset >= 100ns */
32 gpio_set_value(st->pdata->gpio_reset, 0);
39 static int ad7606_scan_direct(struct iio_dev *indio_dev, unsigned ch)
41 struct ad7606_state *st = iio_priv(indio_dev);
45 gpio_set_value(st->pdata->gpio_convst, 1);
47 ret = wait_event_interruptible(st->wq_data_avail, st->done);
51 if (gpio_is_valid(st->pdata->gpio_frstdata)) {
52 ret = st->bops->read_block(st->dev, 1, st->data);
55 if (!gpio_get_value(st->pdata->gpio_frstdata)) {
56 /* This should never happen */
61 ret = st->bops->read_block(st->dev,
62 st->chip_info->num_channels - 1, &st->data[1]);
66 ret = st->bops->read_block(st->dev,
67 st->chip_info->num_channels, st->data);
75 gpio_set_value(st->pdata->gpio_convst, 0);
80 static int ad7606_read_raw(struct iio_dev *indio_dev,
81 struct iio_chan_spec const *chan,
87 struct ad7606_state *st = iio_priv(indio_dev);
90 case IIO_CHAN_INFO_RAW:
91 mutex_lock(&indio_dev->mlock);
92 if (iio_buffer_enabled(indio_dev))
95 ret = ad7606_scan_direct(indio_dev, chan->address);
96 mutex_unlock(&indio_dev->mlock);
102 case IIO_CHAN_INFO_SCALE:
103 *val = st->range * 2;
104 *val2 = st->chip_info->channels[0].scan_type.realbits;
105 return IIO_VAL_FRACTIONAL_LOG2;
110 static ssize_t ad7606_show_range(struct device *dev,
111 struct device_attribute *attr, char *buf)
113 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
114 struct ad7606_state *st = iio_priv(indio_dev);
116 return sprintf(buf, "%u\n", st->range);
119 static ssize_t ad7606_store_range(struct device *dev,
120 struct device_attribute *attr,
121 const char *buf, size_t count)
123 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
124 struct ad7606_state *st = iio_priv(indio_dev);
128 ret = kstrtoul(buf, 10, &lval);
132 if (!(lval == 5000 || lval == 10000)) {
133 dev_err(dev, "range is not supported\n");
136 mutex_lock(&indio_dev->mlock);
137 gpio_set_value(st->pdata->gpio_range, lval == 10000);
139 mutex_unlock(&indio_dev->mlock);
144 static IIO_DEVICE_ATTR(in_voltage_range, S_IRUGO | S_IWUSR,
145 ad7606_show_range, ad7606_store_range, 0);
146 static IIO_CONST_ATTR(in_voltage_range_available, "5000 10000");
148 static ssize_t ad7606_show_oversampling_ratio(struct device *dev,
149 struct device_attribute *attr,
152 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
153 struct ad7606_state *st = iio_priv(indio_dev);
155 return sprintf(buf, "%u\n", st->oversampling);
158 static int ad7606_oversampling_get_index(unsigned val)
160 unsigned char supported[] = {0, 2, 4, 8, 16, 32, 64};
163 for (i = 0; i < ARRAY_SIZE(supported); i++)
164 if (val == supported[i])
170 static ssize_t ad7606_store_oversampling_ratio(struct device *dev,
171 struct device_attribute *attr,
172 const char *buf, size_t count)
174 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
175 struct ad7606_state *st = iio_priv(indio_dev);
179 ret = kstrtoul(buf, 10, &lval);
183 ret = ad7606_oversampling_get_index(lval);
185 dev_err(dev, "oversampling %lu is not supported\n", lval);
189 mutex_lock(&indio_dev->mlock);
190 gpio_set_value(st->pdata->gpio_os0, (ret >> 0) & 1);
191 gpio_set_value(st->pdata->gpio_os1, (ret >> 1) & 1);
192 gpio_set_value(st->pdata->gpio_os1, (ret >> 2) & 1);
193 st->oversampling = lval;
194 mutex_unlock(&indio_dev->mlock);
199 static IIO_DEVICE_ATTR(oversampling_ratio, S_IRUGO | S_IWUSR,
200 ad7606_show_oversampling_ratio,
201 ad7606_store_oversampling_ratio, 0);
202 static IIO_CONST_ATTR(oversampling_ratio_available, "0 2 4 8 16 32 64");
204 static struct attribute *ad7606_attributes_os_and_range[] = {
205 &iio_dev_attr_in_voltage_range.dev_attr.attr,
206 &iio_const_attr_in_voltage_range_available.dev_attr.attr,
207 &iio_dev_attr_oversampling_ratio.dev_attr.attr,
208 &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
212 static const struct attribute_group ad7606_attribute_group_os_and_range = {
213 .attrs = ad7606_attributes_os_and_range,
216 static struct attribute *ad7606_attributes_os[] = {
217 &iio_dev_attr_oversampling_ratio.dev_attr.attr,
218 &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
222 static const struct attribute_group ad7606_attribute_group_os = {
223 .attrs = ad7606_attributes_os,
226 static struct attribute *ad7606_attributes_range[] = {
227 &iio_dev_attr_in_voltage_range.dev_attr.attr,
228 &iio_const_attr_in_voltage_range_available.dev_attr.attr,
232 static const struct attribute_group ad7606_attribute_group_range = {
233 .attrs = ad7606_attributes_range,
236 #define AD7606_CHANNEL(num) \
238 .type = IIO_VOLTAGE, \
242 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
243 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
249 .endianness = IIO_CPU, \
253 static const struct iio_chan_spec ad7606_8_channels[] = {
262 IIO_CHAN_SOFT_TIMESTAMP(8),
265 static const struct iio_chan_spec ad7606_6_channels[] = {
272 IIO_CHAN_SOFT_TIMESTAMP(6),
275 static const struct iio_chan_spec ad7606_4_channels[] = {
280 IIO_CHAN_SOFT_TIMESTAMP(4),
283 static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
285 * More devices added in future
290 .channels = ad7606_8_channels,
296 .channels = ad7606_6_channels,
302 .channels = ad7606_4_channels,
307 static int ad7606_request_gpios(struct ad7606_state *st)
309 struct gpio gpio_array[3] = {
311 .gpio = st->pdata->gpio_os0,
312 .flags = GPIOF_DIR_OUT | ((st->oversampling & 1) ?
313 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
314 .label = "AD7606_OS0",
317 .gpio = st->pdata->gpio_os1,
318 .flags = GPIOF_DIR_OUT | ((st->oversampling & 2) ?
319 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
320 .label = "AD7606_OS1",
323 .gpio = st->pdata->gpio_os2,
324 .flags = GPIOF_DIR_OUT | ((st->oversampling & 4) ?
325 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
326 .label = "AD7606_OS2",
331 if (gpio_is_valid(st->pdata->gpio_convst)) {
332 ret = gpio_request_one(st->pdata->gpio_convst,
336 dev_err(st->dev, "failed to request GPIO CONVST\n");
344 if (gpio_is_valid(st->pdata->gpio_os0) &&
345 gpio_is_valid(st->pdata->gpio_os1) &&
346 gpio_is_valid(st->pdata->gpio_os2)) {
347 ret = gpio_request_array(gpio_array, ARRAY_SIZE(gpio_array));
349 goto error_free_convst;
352 if (gpio_is_valid(st->pdata->gpio_reset)) {
353 ret = gpio_request_one(st->pdata->gpio_reset,
360 if (gpio_is_valid(st->pdata->gpio_range)) {
361 ret = gpio_request_one(st->pdata->gpio_range, GPIOF_DIR_OUT |
362 ((st->range == 10000) ? GPIOF_INIT_HIGH :
363 GPIOF_INIT_LOW), "AD7606_RANGE");
365 goto error_free_reset;
367 if (gpio_is_valid(st->pdata->gpio_stby)) {
368 ret = gpio_request_one(st->pdata->gpio_stby,
372 goto error_free_range;
375 if (gpio_is_valid(st->pdata->gpio_frstdata)) {
376 ret = gpio_request_one(st->pdata->gpio_frstdata, GPIOF_IN,
379 goto error_free_stby;
385 if (gpio_is_valid(st->pdata->gpio_stby))
386 gpio_free(st->pdata->gpio_stby);
388 if (gpio_is_valid(st->pdata->gpio_range))
389 gpio_free(st->pdata->gpio_range);
391 if (gpio_is_valid(st->pdata->gpio_reset))
392 gpio_free(st->pdata->gpio_reset);
394 if (gpio_is_valid(st->pdata->gpio_os0) &&
395 gpio_is_valid(st->pdata->gpio_os1) &&
396 gpio_is_valid(st->pdata->gpio_os2))
397 gpio_free_array(gpio_array, ARRAY_SIZE(gpio_array));
399 gpio_free(st->pdata->gpio_convst);
404 static void ad7606_free_gpios(struct ad7606_state *st)
406 if (gpio_is_valid(st->pdata->gpio_frstdata))
407 gpio_free(st->pdata->gpio_frstdata);
408 if (gpio_is_valid(st->pdata->gpio_stby))
409 gpio_free(st->pdata->gpio_stby);
410 if (gpio_is_valid(st->pdata->gpio_range))
411 gpio_free(st->pdata->gpio_range);
412 if (gpio_is_valid(st->pdata->gpio_reset))
413 gpio_free(st->pdata->gpio_reset);
414 if (gpio_is_valid(st->pdata->gpio_os0) &&
415 gpio_is_valid(st->pdata->gpio_os1) &&
416 gpio_is_valid(st->pdata->gpio_os2)) {
417 gpio_free(st->pdata->gpio_os2);
418 gpio_free(st->pdata->gpio_os1);
419 gpio_free(st->pdata->gpio_os0);
421 gpio_free(st->pdata->gpio_convst);
427 static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
429 struct iio_dev *indio_dev = dev_id;
430 struct ad7606_state *st = iio_priv(indio_dev);
432 if (iio_buffer_enabled(indio_dev)) {
433 schedule_work(&st->poll_work);
436 wake_up_interruptible(&st->wq_data_avail);
442 static const struct iio_info ad7606_info_no_os_or_range = {
443 .driver_module = THIS_MODULE,
444 .read_raw = &ad7606_read_raw,
447 static const struct iio_info ad7606_info_os_and_range = {
448 .driver_module = THIS_MODULE,
449 .read_raw = &ad7606_read_raw,
450 .attrs = &ad7606_attribute_group_os_and_range,
453 static const struct iio_info ad7606_info_os = {
454 .driver_module = THIS_MODULE,
455 .read_raw = &ad7606_read_raw,
456 .attrs = &ad7606_attribute_group_os,
459 static const struct iio_info ad7606_info_range = {
460 .driver_module = THIS_MODULE,
461 .read_raw = &ad7606_read_raw,
462 .attrs = &ad7606_attribute_group_range,
465 struct iio_dev *ad7606_probe(struct device *dev, int irq,
466 void __iomem *base_address,
468 const struct ad7606_bus_ops *bops)
470 struct ad7606_platform_data *pdata = dev->platform_data;
471 struct ad7606_state *st;
473 struct iio_dev *indio_dev;
475 indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
477 return ERR_PTR(-ENOMEM);
479 st = iio_priv(indio_dev);
483 st->base_address = base_address;
484 st->range = pdata->default_range == 10000 ? 10000 : 5000;
486 ret = ad7606_oversampling_get_index(pdata->default_os);
488 dev_warn(dev, "oversampling %d is not supported\n",
490 st->oversampling = 0;
492 st->oversampling = pdata->default_os;
495 st->reg = devm_regulator_get(dev, "vcc");
496 if (!IS_ERR(st->reg)) {
497 ret = regulator_enable(st->reg);
503 st->chip_info = &ad7606_chip_info_tbl[id];
505 indio_dev->dev.parent = dev;
506 if (gpio_is_valid(st->pdata->gpio_os0) &&
507 gpio_is_valid(st->pdata->gpio_os1) &&
508 gpio_is_valid(st->pdata->gpio_os2)) {
509 if (gpio_is_valid(st->pdata->gpio_range))
510 indio_dev->info = &ad7606_info_os_and_range;
512 indio_dev->info = &ad7606_info_os;
514 if (gpio_is_valid(st->pdata->gpio_range))
515 indio_dev->info = &ad7606_info_range;
517 indio_dev->info = &ad7606_info_no_os_or_range;
519 indio_dev->modes = INDIO_DIRECT_MODE;
520 indio_dev->name = st->chip_info->name;
521 indio_dev->channels = st->chip_info->channels;
522 indio_dev->num_channels = st->chip_info->num_channels;
524 init_waitqueue_head(&st->wq_data_avail);
526 ret = ad7606_request_gpios(st);
528 goto error_disable_reg;
530 ret = ad7606_reset(st);
532 dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
534 ret = request_irq(irq, ad7606_interrupt,
535 IRQF_TRIGGER_FALLING, st->chip_info->name, indio_dev);
537 goto error_free_gpios;
539 ret = ad7606_register_ring_funcs_and_init(indio_dev);
543 ret = iio_device_register(indio_dev);
545 goto error_unregister_ring;
548 error_unregister_ring:
549 ad7606_ring_cleanup(indio_dev);
552 free_irq(irq, indio_dev);
555 ad7606_free_gpios(st);
558 if (!IS_ERR(st->reg))
559 regulator_disable(st->reg);
563 int ad7606_remove(struct iio_dev *indio_dev, int irq)
565 struct ad7606_state *st = iio_priv(indio_dev);
567 iio_device_unregister(indio_dev);
568 ad7606_ring_cleanup(indio_dev);
570 free_irq(irq, indio_dev);
571 if (!IS_ERR(st->reg))
572 regulator_disable(st->reg);
574 ad7606_free_gpios(st);
579 void ad7606_suspend(struct iio_dev *indio_dev)
581 struct ad7606_state *st = iio_priv(indio_dev);
583 if (gpio_is_valid(st->pdata->gpio_stby)) {
584 if (gpio_is_valid(st->pdata->gpio_range))
585 gpio_set_value(st->pdata->gpio_range, 1);
586 gpio_set_value(st->pdata->gpio_stby, 0);
590 void ad7606_resume(struct iio_dev *indio_dev)
592 struct ad7606_state *st = iio_priv(indio_dev);
594 if (gpio_is_valid(st->pdata->gpio_stby)) {
595 if (gpio_is_valid(st->pdata->gpio_range))
596 gpio_set_value(st->pdata->gpio_range,
599 gpio_set_value(st->pdata->gpio_stby, 1);
604 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
605 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
606 MODULE_LICENSE("GPL v2");