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 int 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 ret = iio_device_claim_direct_mode(indio_dev);
95 ret = ad7606_scan_direct(indio_dev, chan->address);
96 iio_device_release_direct_mode(indio_dev);
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;
106 case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
107 *val = st->oversampling;
113 static ssize_t ad7606_show_range(struct device *dev,
114 struct device_attribute *attr, char *buf)
116 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
117 struct ad7606_state *st = iio_priv(indio_dev);
119 return sprintf(buf, "%u\n", st->range);
122 static ssize_t ad7606_store_range(struct device *dev,
123 struct device_attribute *attr,
124 const char *buf, size_t count)
126 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
127 struct ad7606_state *st = iio_priv(indio_dev);
131 ret = kstrtoul(buf, 10, &lval);
135 if (!(lval == 5000 || lval == 10000)) {
136 dev_err(dev, "range is not supported\n");
139 mutex_lock(&indio_dev->mlock);
140 gpio_set_value(st->pdata->gpio_range, lval == 10000);
142 mutex_unlock(&indio_dev->mlock);
147 static IIO_DEVICE_ATTR(in_voltage_range, S_IRUGO | S_IWUSR,
148 ad7606_show_range, ad7606_store_range, 0);
149 static IIO_CONST_ATTR(in_voltage_range_available, "5000 10000");
151 static int ad7606_oversampling_get_index(unsigned int val)
153 unsigned char supported[] = {0, 2, 4, 8, 16, 32, 64};
156 for (i = 0; i < ARRAY_SIZE(supported); i++)
157 if (val == supported[i])
163 static int ad7606_write_raw(struct iio_dev *indio_dev,
164 struct iio_chan_spec const *chan,
169 struct ad7606_state *st = iio_priv(indio_dev);
173 case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
176 ret = ad7606_oversampling_get_index(val);
178 dev_err(st->dev, "oversampling %d is not supported\n",
183 mutex_lock(&indio_dev->mlock);
184 gpio_set_value(st->pdata->gpio_os0, (ret >> 0) & 1);
185 gpio_set_value(st->pdata->gpio_os1, (ret >> 1) & 1);
186 gpio_set_value(st->pdata->gpio_os2, (ret >> 2) & 1);
187 st->oversampling = val;
188 mutex_unlock(&indio_dev->mlock);
195 static IIO_CONST_ATTR(oversampling_ratio_available, "0 2 4 8 16 32 64");
197 static struct attribute *ad7606_attributes_os_and_range[] = {
198 &iio_dev_attr_in_voltage_range.dev_attr.attr,
199 &iio_const_attr_in_voltage_range_available.dev_attr.attr,
200 &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
204 static const struct attribute_group ad7606_attribute_group_os_and_range = {
205 .attrs = ad7606_attributes_os_and_range,
208 static struct attribute *ad7606_attributes_os[] = {
209 &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
213 static const struct attribute_group ad7606_attribute_group_os = {
214 .attrs = ad7606_attributes_os,
217 static struct attribute *ad7606_attributes_range[] = {
218 &iio_dev_attr_in_voltage_range.dev_attr.attr,
219 &iio_const_attr_in_voltage_range_available.dev_attr.attr,
223 static const struct attribute_group ad7606_attribute_group_range = {
224 .attrs = ad7606_attributes_range,
227 #define AD7606_CHANNEL(num) \
229 .type = IIO_VOLTAGE, \
233 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
234 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
235 .info_mask_shared_by_all = \
236 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
242 .endianness = IIO_CPU, \
246 static const struct iio_chan_spec ad7606_channels[] = {
247 IIO_CHAN_SOFT_TIMESTAMP(8),
258 static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
260 * More devices added in future
265 .channels = ad7606_channels,
271 .channels = ad7606_channels,
277 .channels = ad7606_channels,
282 static int ad7606_request_gpios(struct ad7606_state *st)
284 struct gpio gpio_array[3] = {
286 .gpio = st->pdata->gpio_os0,
287 .flags = GPIOF_DIR_OUT | ((st->oversampling & 1) ?
288 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
289 .label = "AD7606_OS0",
292 .gpio = st->pdata->gpio_os1,
293 .flags = GPIOF_DIR_OUT | ((st->oversampling & 2) ?
294 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
295 .label = "AD7606_OS1",
298 .gpio = st->pdata->gpio_os2,
299 .flags = GPIOF_DIR_OUT | ((st->oversampling & 4) ?
300 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
301 .label = "AD7606_OS2",
306 if (gpio_is_valid(st->pdata->gpio_convst)) {
307 ret = gpio_request_one(st->pdata->gpio_convst,
311 dev_err(st->dev, "failed to request GPIO CONVST\n");
319 if (gpio_is_valid(st->pdata->gpio_os0) &&
320 gpio_is_valid(st->pdata->gpio_os1) &&
321 gpio_is_valid(st->pdata->gpio_os2)) {
322 ret = gpio_request_array(gpio_array, ARRAY_SIZE(gpio_array));
324 goto error_free_convst;
327 if (gpio_is_valid(st->pdata->gpio_reset)) {
328 ret = gpio_request_one(st->pdata->gpio_reset,
335 if (gpio_is_valid(st->pdata->gpio_range)) {
336 ret = gpio_request_one(st->pdata->gpio_range, GPIOF_DIR_OUT |
337 ((st->range == 10000) ? GPIOF_INIT_HIGH :
338 GPIOF_INIT_LOW), "AD7606_RANGE");
340 goto error_free_reset;
342 if (gpio_is_valid(st->pdata->gpio_stby)) {
343 ret = gpio_request_one(st->pdata->gpio_stby,
347 goto error_free_range;
350 if (gpio_is_valid(st->pdata->gpio_frstdata)) {
351 ret = gpio_request_one(st->pdata->gpio_frstdata, GPIOF_IN,
354 goto error_free_stby;
360 if (gpio_is_valid(st->pdata->gpio_stby))
361 gpio_free(st->pdata->gpio_stby);
363 if (gpio_is_valid(st->pdata->gpio_range))
364 gpio_free(st->pdata->gpio_range);
366 if (gpio_is_valid(st->pdata->gpio_reset))
367 gpio_free(st->pdata->gpio_reset);
369 if (gpio_is_valid(st->pdata->gpio_os0) &&
370 gpio_is_valid(st->pdata->gpio_os1) &&
371 gpio_is_valid(st->pdata->gpio_os2))
372 gpio_free_array(gpio_array, ARRAY_SIZE(gpio_array));
374 gpio_free(st->pdata->gpio_convst);
379 static void ad7606_free_gpios(struct ad7606_state *st)
381 if (gpio_is_valid(st->pdata->gpio_frstdata))
382 gpio_free(st->pdata->gpio_frstdata);
383 if (gpio_is_valid(st->pdata->gpio_stby))
384 gpio_free(st->pdata->gpio_stby);
385 if (gpio_is_valid(st->pdata->gpio_range))
386 gpio_free(st->pdata->gpio_range);
387 if (gpio_is_valid(st->pdata->gpio_reset))
388 gpio_free(st->pdata->gpio_reset);
389 if (gpio_is_valid(st->pdata->gpio_os0) &&
390 gpio_is_valid(st->pdata->gpio_os1) &&
391 gpio_is_valid(st->pdata->gpio_os2)) {
392 gpio_free(st->pdata->gpio_os2);
393 gpio_free(st->pdata->gpio_os1);
394 gpio_free(st->pdata->gpio_os0);
396 gpio_free(st->pdata->gpio_convst);
402 static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
404 struct iio_dev *indio_dev = dev_id;
405 struct ad7606_state *st = iio_priv(indio_dev);
407 if (iio_buffer_enabled(indio_dev)) {
408 schedule_work(&st->poll_work);
411 wake_up_interruptible(&st->wq_data_avail);
417 static const struct iio_info ad7606_info_no_os_or_range = {
418 .driver_module = THIS_MODULE,
419 .read_raw = &ad7606_read_raw,
422 static const struct iio_info ad7606_info_os_and_range = {
423 .driver_module = THIS_MODULE,
424 .read_raw = &ad7606_read_raw,
425 .write_raw = &ad7606_write_raw,
426 .attrs = &ad7606_attribute_group_os_and_range,
429 static const struct iio_info ad7606_info_os = {
430 .driver_module = THIS_MODULE,
431 .read_raw = &ad7606_read_raw,
432 .write_raw = &ad7606_write_raw,
433 .attrs = &ad7606_attribute_group_os,
436 static const struct iio_info ad7606_info_range = {
437 .driver_module = THIS_MODULE,
438 .read_raw = &ad7606_read_raw,
439 .attrs = &ad7606_attribute_group_range,
442 struct iio_dev *ad7606_probe(struct device *dev, int irq,
443 void __iomem *base_address,
445 const struct ad7606_bus_ops *bops)
447 struct ad7606_platform_data *pdata = dev->platform_data;
448 struct ad7606_state *st;
450 struct iio_dev *indio_dev;
452 indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
454 return ERR_PTR(-ENOMEM);
456 st = iio_priv(indio_dev);
460 st->base_address = base_address;
461 st->range = pdata->default_range == 10000 ? 10000 : 5000;
463 ret = ad7606_oversampling_get_index(pdata->default_os);
465 dev_warn(dev, "oversampling %d is not supported\n",
467 st->oversampling = 0;
469 st->oversampling = pdata->default_os;
472 st->reg = devm_regulator_get(dev, "vcc");
473 if (!IS_ERR(st->reg)) {
474 ret = regulator_enable(st->reg);
480 st->chip_info = &ad7606_chip_info_tbl[id];
482 indio_dev->dev.parent = dev;
483 if (gpio_is_valid(st->pdata->gpio_os0) &&
484 gpio_is_valid(st->pdata->gpio_os1) &&
485 gpio_is_valid(st->pdata->gpio_os2)) {
486 if (gpio_is_valid(st->pdata->gpio_range))
487 indio_dev->info = &ad7606_info_os_and_range;
489 indio_dev->info = &ad7606_info_os;
491 if (gpio_is_valid(st->pdata->gpio_range))
492 indio_dev->info = &ad7606_info_range;
494 indio_dev->info = &ad7606_info_no_os_or_range;
496 indio_dev->modes = INDIO_DIRECT_MODE;
497 indio_dev->name = st->chip_info->name;
498 indio_dev->channels = st->chip_info->channels;
499 indio_dev->num_channels = st->chip_info->num_channels;
501 init_waitqueue_head(&st->wq_data_avail);
503 ret = ad7606_request_gpios(st);
505 goto error_disable_reg;
507 ret = ad7606_reset(st);
509 dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
511 ret = request_irq(irq, ad7606_interrupt,
512 IRQF_TRIGGER_FALLING, st->chip_info->name, indio_dev);
514 goto error_free_gpios;
516 ret = ad7606_register_ring_funcs_and_init(indio_dev);
520 ret = iio_device_register(indio_dev);
522 goto error_unregister_ring;
525 error_unregister_ring:
526 ad7606_ring_cleanup(indio_dev);
529 free_irq(irq, indio_dev);
532 ad7606_free_gpios(st);
535 if (!IS_ERR(st->reg))
536 regulator_disable(st->reg);
539 EXPORT_SYMBOL_GPL(ad7606_probe);
541 int ad7606_remove(struct iio_dev *indio_dev, int irq)
543 struct ad7606_state *st = iio_priv(indio_dev);
545 iio_device_unregister(indio_dev);
546 ad7606_ring_cleanup(indio_dev);
548 free_irq(irq, indio_dev);
549 if (!IS_ERR(st->reg))
550 regulator_disable(st->reg);
552 ad7606_free_gpios(st);
556 EXPORT_SYMBOL_GPL(ad7606_remove);
558 #ifdef CONFIG_PM_SLEEP
560 static int ad7606_suspend(struct device *dev)
562 struct iio_dev *indio_dev = dev_get_drvdata(dev);
563 struct ad7606_state *st = iio_priv(indio_dev);
565 if (gpio_is_valid(st->pdata->gpio_stby)) {
566 if (gpio_is_valid(st->pdata->gpio_range))
567 gpio_set_value(st->pdata->gpio_range, 1);
568 gpio_set_value(st->pdata->gpio_stby, 0);
574 static int ad7606_resume(struct device *dev)
576 struct iio_dev *indio_dev = dev_get_drvdata(dev);
577 struct ad7606_state *st = iio_priv(indio_dev);
579 if (gpio_is_valid(st->pdata->gpio_stby)) {
580 if (gpio_is_valid(st->pdata->gpio_range))
581 gpio_set_value(st->pdata->gpio_range,
584 gpio_set_value(st->pdata->gpio_stby, 1);
591 SIMPLE_DEV_PM_OPS(ad7606_pm_ops, ad7606_suspend, ad7606_resume);
592 EXPORT_SYMBOL_GPL(ad7606_pm_ops);
596 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
597 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
598 MODULE_LICENSE("GPL v2");