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
263 .channels = ad7606_channels,
267 .channels = ad7606_channels,
271 .channels = ad7606_channels,
276 static int ad7606_request_gpios(struct ad7606_state *st)
278 struct gpio gpio_array[3] = {
280 .gpio = st->pdata->gpio_os0,
281 .flags = GPIOF_DIR_OUT | ((st->oversampling & 1) ?
282 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
283 .label = "AD7606_OS0",
286 .gpio = st->pdata->gpio_os1,
287 .flags = GPIOF_DIR_OUT | ((st->oversampling & 2) ?
288 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
289 .label = "AD7606_OS1",
292 .gpio = st->pdata->gpio_os2,
293 .flags = GPIOF_DIR_OUT | ((st->oversampling & 4) ?
294 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
295 .label = "AD7606_OS2",
300 if (gpio_is_valid(st->pdata->gpio_convst)) {
301 ret = gpio_request_one(st->pdata->gpio_convst,
305 dev_err(st->dev, "failed to request GPIO CONVST\n");
313 if (gpio_is_valid(st->pdata->gpio_os0) &&
314 gpio_is_valid(st->pdata->gpio_os1) &&
315 gpio_is_valid(st->pdata->gpio_os2)) {
316 ret = gpio_request_array(gpio_array, ARRAY_SIZE(gpio_array));
318 goto error_free_convst;
321 if (gpio_is_valid(st->pdata->gpio_reset)) {
322 ret = gpio_request_one(st->pdata->gpio_reset,
329 if (gpio_is_valid(st->pdata->gpio_range)) {
330 ret = gpio_request_one(st->pdata->gpio_range, GPIOF_DIR_OUT |
331 ((st->range == 10000) ? GPIOF_INIT_HIGH :
332 GPIOF_INIT_LOW), "AD7606_RANGE");
334 goto error_free_reset;
336 if (gpio_is_valid(st->pdata->gpio_stby)) {
337 ret = gpio_request_one(st->pdata->gpio_stby,
341 goto error_free_range;
344 if (gpio_is_valid(st->pdata->gpio_frstdata)) {
345 ret = gpio_request_one(st->pdata->gpio_frstdata, GPIOF_IN,
348 goto error_free_stby;
354 if (gpio_is_valid(st->pdata->gpio_stby))
355 gpio_free(st->pdata->gpio_stby);
357 if (gpio_is_valid(st->pdata->gpio_range))
358 gpio_free(st->pdata->gpio_range);
360 if (gpio_is_valid(st->pdata->gpio_reset))
361 gpio_free(st->pdata->gpio_reset);
363 if (gpio_is_valid(st->pdata->gpio_os0) &&
364 gpio_is_valid(st->pdata->gpio_os1) &&
365 gpio_is_valid(st->pdata->gpio_os2))
366 gpio_free_array(gpio_array, ARRAY_SIZE(gpio_array));
368 gpio_free(st->pdata->gpio_convst);
373 static void ad7606_free_gpios(struct ad7606_state *st)
375 if (gpio_is_valid(st->pdata->gpio_frstdata))
376 gpio_free(st->pdata->gpio_frstdata);
377 if (gpio_is_valid(st->pdata->gpio_stby))
378 gpio_free(st->pdata->gpio_stby);
379 if (gpio_is_valid(st->pdata->gpio_range))
380 gpio_free(st->pdata->gpio_range);
381 if (gpio_is_valid(st->pdata->gpio_reset))
382 gpio_free(st->pdata->gpio_reset);
383 if (gpio_is_valid(st->pdata->gpio_os0) &&
384 gpio_is_valid(st->pdata->gpio_os1) &&
385 gpio_is_valid(st->pdata->gpio_os2)) {
386 gpio_free(st->pdata->gpio_os2);
387 gpio_free(st->pdata->gpio_os1);
388 gpio_free(st->pdata->gpio_os0);
390 gpio_free(st->pdata->gpio_convst);
396 static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
398 struct iio_dev *indio_dev = dev_id;
399 struct ad7606_state *st = iio_priv(indio_dev);
401 if (iio_buffer_enabled(indio_dev)) {
402 schedule_work(&st->poll_work);
405 wake_up_interruptible(&st->wq_data_avail);
411 static const struct iio_info ad7606_info_no_os_or_range = {
412 .driver_module = THIS_MODULE,
413 .read_raw = &ad7606_read_raw,
416 static const struct iio_info ad7606_info_os_and_range = {
417 .driver_module = THIS_MODULE,
418 .read_raw = &ad7606_read_raw,
419 .write_raw = &ad7606_write_raw,
420 .attrs = &ad7606_attribute_group_os_and_range,
423 static const struct iio_info ad7606_info_os = {
424 .driver_module = THIS_MODULE,
425 .read_raw = &ad7606_read_raw,
426 .write_raw = &ad7606_write_raw,
427 .attrs = &ad7606_attribute_group_os,
430 static const struct iio_info ad7606_info_range = {
431 .driver_module = THIS_MODULE,
432 .read_raw = &ad7606_read_raw,
433 .attrs = &ad7606_attribute_group_range,
436 struct iio_dev *ad7606_probe(struct device *dev, int irq,
437 void __iomem *base_address,
438 const char *name, unsigned int id,
439 const struct ad7606_bus_ops *bops)
441 struct ad7606_platform_data *pdata = dev->platform_data;
442 struct ad7606_state *st;
444 struct iio_dev *indio_dev;
446 indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
448 return ERR_PTR(-ENOMEM);
450 st = iio_priv(indio_dev);
454 st->base_address = base_address;
456 st->oversampling = 0;
458 st->reg = devm_regulator_get(dev, "vcc");
459 if (!IS_ERR(st->reg)) {
460 ret = regulator_enable(st->reg);
466 st->chip_info = &ad7606_chip_info_tbl[id];
468 indio_dev->dev.parent = dev;
469 if (gpio_is_valid(st->pdata->gpio_os0) &&
470 gpio_is_valid(st->pdata->gpio_os1) &&
471 gpio_is_valid(st->pdata->gpio_os2)) {
472 if (gpio_is_valid(st->pdata->gpio_range))
473 indio_dev->info = &ad7606_info_os_and_range;
475 indio_dev->info = &ad7606_info_os;
477 if (gpio_is_valid(st->pdata->gpio_range))
478 indio_dev->info = &ad7606_info_range;
480 indio_dev->info = &ad7606_info_no_os_or_range;
482 indio_dev->modes = INDIO_DIRECT_MODE;
483 indio_dev->name = name;
484 indio_dev->channels = st->chip_info->channels;
485 indio_dev->num_channels = st->chip_info->num_channels;
487 init_waitqueue_head(&st->wq_data_avail);
489 ret = ad7606_request_gpios(st);
491 goto error_disable_reg;
493 ret = ad7606_reset(st);
495 dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
497 ret = request_irq(irq, ad7606_interrupt, IRQF_TRIGGER_FALLING, name,
500 goto error_free_gpios;
502 ret = ad7606_register_ring_funcs_and_init(indio_dev);
506 ret = iio_device_register(indio_dev);
508 goto error_unregister_ring;
511 error_unregister_ring:
512 ad7606_ring_cleanup(indio_dev);
515 free_irq(irq, indio_dev);
518 ad7606_free_gpios(st);
521 if (!IS_ERR(st->reg))
522 regulator_disable(st->reg);
525 EXPORT_SYMBOL_GPL(ad7606_probe);
527 int ad7606_remove(struct iio_dev *indio_dev, int irq)
529 struct ad7606_state *st = iio_priv(indio_dev);
531 iio_device_unregister(indio_dev);
532 ad7606_ring_cleanup(indio_dev);
534 free_irq(irq, indio_dev);
535 if (!IS_ERR(st->reg))
536 regulator_disable(st->reg);
538 ad7606_free_gpios(st);
542 EXPORT_SYMBOL_GPL(ad7606_remove);
544 #ifdef CONFIG_PM_SLEEP
546 static int ad7606_suspend(struct device *dev)
548 struct iio_dev *indio_dev = dev_get_drvdata(dev);
549 struct ad7606_state *st = iio_priv(indio_dev);
551 if (gpio_is_valid(st->pdata->gpio_stby)) {
552 if (gpio_is_valid(st->pdata->gpio_range))
553 gpio_set_value(st->pdata->gpio_range, 1);
554 gpio_set_value(st->pdata->gpio_stby, 0);
560 static int ad7606_resume(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,
570 gpio_set_value(st->pdata->gpio_stby, 1);
577 SIMPLE_DEV_PM_OPS(ad7606_pm_ops, ad7606_suspend, ad7606_resume);
578 EXPORT_SYMBOL_GPL(ad7606_pm_ops);
582 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
583 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
584 MODULE_LICENSE("GPL v2");