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>
23 #include "../buffer_generic.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);
88 unsigned int scale_uv;
92 mutex_lock(&indio_dev->mlock);
93 if (iio_buffer_enabled(indio_dev))
94 ret = ad7606_scan_from_ring(indio_dev, chan->address);
96 ret = ad7606_scan_direct(indio_dev, chan->address);
97 mutex_unlock(&indio_dev->mlock);
103 case (1 << IIO_CHAN_INFO_SCALE_SHARED):
104 scale_uv = (st->range * 1000 * 2)
105 >> st->chip_info->channels[0].scan_type.realbits;
106 *val = scale_uv / 1000;
107 *val2 = (scale_uv % 1000) * 1000;
108 return IIO_VAL_INT_PLUS_MICRO;
113 static ssize_t ad7606_show_range(struct device *dev,
114 struct device_attribute *attr, char *buf)
116 struct iio_dev *indio_dev = dev_get_drvdata(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, const char *buf, size_t count)
125 struct iio_dev *indio_dev = dev_get_drvdata(dev);
126 struct ad7606_state *st = iio_priv(indio_dev);
129 if (strict_strtoul(buf, 10, &lval))
131 if (!(lval == 5000 || lval == 10000)) {
132 dev_err(dev, "range is not supported\n");
135 mutex_lock(&indio_dev->mlock);
136 gpio_set_value(st->pdata->gpio_range, lval == 10000);
138 mutex_unlock(&indio_dev->mlock);
143 static IIO_DEVICE_ATTR(in_voltage_range, S_IRUGO | S_IWUSR, \
144 ad7606_show_range, ad7606_store_range, 0);
145 static IIO_CONST_ATTR(in_voltage_range_available, "5000 10000");
147 static ssize_t ad7606_show_oversampling_ratio(struct device *dev,
148 struct device_attribute *attr, char *buf)
150 struct iio_dev *indio_dev = dev_get_drvdata(dev);
151 struct ad7606_state *st = iio_priv(indio_dev);
153 return sprintf(buf, "%u\n", st->oversampling);
156 static int ad7606_oversampling_get_index(unsigned val)
158 unsigned char supported[] = {0, 2, 4, 8, 16, 32, 64};
161 for (i = 0; i < ARRAY_SIZE(supported); i++)
162 if (val == supported[i])
168 static ssize_t ad7606_store_oversampling_ratio(struct device *dev,
169 struct device_attribute *attr, const char *buf, size_t count)
171 struct iio_dev *indio_dev = dev_get_drvdata(dev);
172 struct ad7606_state *st = iio_priv(indio_dev);
176 if (strict_strtoul(buf, 10, &lval))
179 ret = ad7606_oversampling_get_index(lval);
181 dev_err(dev, "oversampling %lu is not supported\n", lval);
185 mutex_lock(&indio_dev->mlock);
186 gpio_set_value(st->pdata->gpio_os0, (ret >> 0) & 1);
187 gpio_set_value(st->pdata->gpio_os1, (ret >> 1) & 1);
188 gpio_set_value(st->pdata->gpio_os2, (ret >> 2) & 1);
189 st->oversampling = lval;
190 mutex_unlock(&indio_dev->mlock);
195 static IIO_DEVICE_ATTR(oversampling_ratio, S_IRUGO | S_IWUSR,
196 ad7606_show_oversampling_ratio,
197 ad7606_store_oversampling_ratio, 0);
198 static IIO_CONST_ATTR(oversampling_ratio_available, "0 2 4 8 16 32 64");
200 static struct attribute *ad7606_attributes[] = {
201 &iio_dev_attr_in_voltage_range.dev_attr.attr,
202 &iio_const_attr_in_voltage_range_available.dev_attr.attr,
203 &iio_dev_attr_oversampling_ratio.dev_attr.attr,
204 &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
208 static mode_t ad7606_attr_is_visible(struct kobject *kobj,
209 struct attribute *attr, int n)
211 struct device *dev = container_of(kobj, struct device, kobj);
212 struct iio_dev *indio_dev = dev_get_drvdata(dev);
213 struct ad7606_state *st = iio_priv(indio_dev);
215 mode_t mode = attr->mode;
217 if (!(gpio_is_valid(st->pdata->gpio_os0) &&
218 gpio_is_valid(st->pdata->gpio_os1) &&
219 gpio_is_valid(st->pdata->gpio_os2)) &&
220 (attr == &iio_dev_attr_oversampling_ratio.dev_attr.attr ||
222 &iio_const_attr_oversampling_ratio_available.dev_attr.attr))
224 else if (!gpio_is_valid(st->pdata->gpio_range) &&
225 (attr == &iio_dev_attr_in_voltage_range.dev_attr.attr ||
227 &iio_const_attr_in_voltage_range_available.dev_attr.attr))
233 static const struct attribute_group ad7606_attribute_group = {
234 .attrs = ad7606_attributes,
235 .is_visible = ad7606_attr_is_visible,
238 #define AD7606_CHANNEL(num) \
240 .type = IIO_VOLTAGE, \
244 .info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED), \
246 .scan_type = IIO_ST('s', 16, 16, 0), \
249 static struct iio_chan_spec ad7606_8_channels[] = {
258 IIO_CHAN_SOFT_TIMESTAMP(8),
261 static struct iio_chan_spec ad7606_6_channels[] = {
268 IIO_CHAN_SOFT_TIMESTAMP(6),
271 static struct iio_chan_spec ad7606_4_channels[] = {
276 IIO_CHAN_SOFT_TIMESTAMP(4),
279 static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
281 * More devices added in future
286 .channels = ad7606_8_channels,
292 .channels = ad7606_6_channels,
298 .channels = ad7606_4_channels,
303 static int ad7606_request_gpios(struct ad7606_state *st)
305 struct gpio gpio_array[3] = {
307 .gpio = st->pdata->gpio_os0,
308 .flags = GPIOF_DIR_OUT | ((st->oversampling & 1) ?
309 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
310 .label = "AD7606_OS0",
313 .gpio = st->pdata->gpio_os1,
314 .flags = GPIOF_DIR_OUT | ((st->oversampling & 2) ?
315 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
316 .label = "AD7606_OS1",
319 .gpio = st->pdata->gpio_os2,
320 .flags = GPIOF_DIR_OUT | ((st->oversampling & 4) ?
321 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
322 .label = "AD7606_OS2",
327 if (gpio_is_valid(st->pdata->gpio_convst)) {
328 ret = gpio_request_one(st->pdata->gpio_convst,
332 dev_err(st->dev, "failed to request GPIO CONVST\n");
340 if (gpio_is_valid(st->pdata->gpio_os0) &&
341 gpio_is_valid(st->pdata->gpio_os1) &&
342 gpio_is_valid(st->pdata->gpio_os2)) {
343 ret = gpio_request_array(gpio_array, ARRAY_SIZE(gpio_array));
345 goto error_free_convst;
348 if (gpio_is_valid(st->pdata->gpio_reset)) {
349 ret = gpio_request_one(st->pdata->gpio_reset,
356 if (gpio_is_valid(st->pdata->gpio_range)) {
357 ret = gpio_request_one(st->pdata->gpio_range, GPIOF_DIR_OUT |
358 ((st->range == 10000) ? GPIOF_INIT_HIGH :
359 GPIOF_INIT_LOW), "AD7606_RANGE");
361 goto error_free_reset;
363 if (gpio_is_valid(st->pdata->gpio_stby)) {
364 ret = gpio_request_one(st->pdata->gpio_stby,
368 goto error_free_range;
371 if (gpio_is_valid(st->pdata->gpio_frstdata)) {
372 ret = gpio_request_one(st->pdata->gpio_frstdata, GPIOF_IN,
375 goto error_free_stby;
381 if (gpio_is_valid(st->pdata->gpio_stby))
382 gpio_free(st->pdata->gpio_stby);
384 if (gpio_is_valid(st->pdata->gpio_range))
385 gpio_free(st->pdata->gpio_range);
387 if (gpio_is_valid(st->pdata->gpio_reset))
388 gpio_free(st->pdata->gpio_reset);
390 if (gpio_is_valid(st->pdata->gpio_os0) &&
391 gpio_is_valid(st->pdata->gpio_os1) &&
392 gpio_is_valid(st->pdata->gpio_os2))
393 gpio_free_array(gpio_array, ARRAY_SIZE(gpio_array));
395 gpio_free(st->pdata->gpio_convst);
400 static void ad7606_free_gpios(struct ad7606_state *st)
402 if (gpio_is_valid(st->pdata->gpio_frstdata))
403 gpio_free(st->pdata->gpio_frstdata);
404 if (gpio_is_valid(st->pdata->gpio_stby))
405 gpio_free(st->pdata->gpio_stby);
406 if (gpio_is_valid(st->pdata->gpio_range))
407 gpio_free(st->pdata->gpio_range);
408 if (gpio_is_valid(st->pdata->gpio_reset))
409 gpio_free(st->pdata->gpio_reset);
410 if (gpio_is_valid(st->pdata->gpio_os0) &&
411 gpio_is_valid(st->pdata->gpio_os1) &&
412 gpio_is_valid(st->pdata->gpio_os2)) {
413 gpio_free(st->pdata->gpio_os2);
414 gpio_free(st->pdata->gpio_os1);
415 gpio_free(st->pdata->gpio_os0);
417 gpio_free(st->pdata->gpio_convst);
423 static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
425 struct iio_dev *indio_dev = dev_id;
426 struct ad7606_state *st = iio_priv(indio_dev);
428 if (iio_buffer_enabled(indio_dev)) {
429 if (!work_pending(&st->poll_work))
430 schedule_work(&st->poll_work);
433 wake_up_interruptible(&st->wq_data_avail);
439 static const struct iio_info ad7606_info = {
440 .driver_module = THIS_MODULE,
441 .read_raw = &ad7606_read_raw,
442 .attrs = &ad7606_attribute_group,
445 struct iio_dev *ad7606_probe(struct device *dev, int irq,
446 void __iomem *base_address,
448 const struct ad7606_bus_ops *bops)
450 struct ad7606_platform_data *pdata = dev->platform_data;
451 struct ad7606_state *st;
453 struct iio_dev *indio_dev = iio_allocate_device(sizeof(*st));
455 if (indio_dev == NULL) {
460 st = iio_priv(indio_dev);
464 st->base_address = base_address;
465 st->range = pdata->default_range == 10000 ? 10000 : 5000;
467 ret = ad7606_oversampling_get_index(pdata->default_os);
469 dev_warn(dev, "oversampling %d is not supported\n",
471 st->oversampling = 0;
473 st->oversampling = pdata->default_os;
476 st->reg = regulator_get(dev, "vcc");
477 if (!IS_ERR(st->reg)) {
478 ret = regulator_enable(st->reg);
484 st->chip_info = &ad7606_chip_info_tbl[id];
486 indio_dev->dev.parent = dev;
487 indio_dev->info = &ad7606_info;
488 indio_dev->modes = INDIO_DIRECT_MODE;
489 indio_dev->name = st->chip_info->name;
490 indio_dev->channels = st->chip_info->channels;
491 indio_dev->num_channels = st->chip_info->num_channels;
493 init_waitqueue_head(&st->wq_data_avail);
495 ret = ad7606_request_gpios(st);
497 goto error_disable_reg;
499 ret = ad7606_reset(st);
501 dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
503 ret = request_irq(irq, ad7606_interrupt,
504 IRQF_TRIGGER_FALLING, st->chip_info->name, indio_dev);
506 goto error_free_gpios;
508 ret = ad7606_register_ring_funcs_and_init(indio_dev);
512 ret = iio_buffer_register(indio_dev,
514 indio_dev->num_channels);
516 goto error_cleanup_ring;
517 ret = iio_device_register(indio_dev);
519 goto error_unregister_ring;
522 error_unregister_ring:
523 iio_buffer_unregister(indio_dev);
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);
538 if (!IS_ERR(st->reg))
539 regulator_put(st->reg);
540 iio_free_device(indio_dev);
545 int ad7606_remove(struct iio_dev *indio_dev, int irq)
547 struct ad7606_state *st = iio_priv(indio_dev);
549 iio_device_unregister(indio_dev);
550 iio_buffer_unregister(indio_dev);
551 ad7606_ring_cleanup(indio_dev);
553 free_irq(irq, indio_dev);
554 if (!IS_ERR(st->reg)) {
555 regulator_disable(st->reg);
556 regulator_put(st->reg);
559 ad7606_free_gpios(st);
560 iio_free_device(indio_dev);
565 void ad7606_suspend(struct iio_dev *indio_dev)
567 struct ad7606_state *st = iio_priv(indio_dev);
569 if (gpio_is_valid(st->pdata->gpio_stby)) {
570 if (gpio_is_valid(st->pdata->gpio_range))
571 gpio_set_value(st->pdata->gpio_range, 1);
572 gpio_set_value(st->pdata->gpio_stby, 0);
576 void ad7606_resume(struct iio_dev *indio_dev)
578 struct ad7606_state *st = iio_priv(indio_dev);
580 if (gpio_is_valid(st->pdata->gpio_stby)) {
581 if (gpio_is_valid(st->pdata->gpio_range))
582 gpio_set_value(st->pdata->gpio_range,
585 gpio_set_value(st->pdata->gpio_stby, 1);
590 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
591 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
592 MODULE_LICENSE("GPL v2");