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);
88 unsigned int scale_uv;
91 case IIO_CHAN_INFO_RAW:
92 mutex_lock(&indio_dev->mlock);
93 if (iio_buffer_enabled(indio_dev))
96 ret = ad7606_scan_direct(indio_dev, chan->address);
97 mutex_unlock(&indio_dev->mlock);
103 case IIO_CHAN_INFO_SCALE:
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_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, const char *buf, size_t count)
125 struct iio_dev *indio_dev = dev_to_iio_dev(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_to_iio_dev(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_to_iio_dev(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_os1, (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_os_and_range[] = {
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 const struct attribute_group ad7606_attribute_group_os_and_range = {
209 .attrs = ad7606_attributes_os_and_range,
212 static struct attribute *ad7606_attributes_os[] = {
213 &iio_dev_attr_oversampling_ratio.dev_attr.attr,
214 &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
218 static const struct attribute_group ad7606_attribute_group_os = {
219 .attrs = ad7606_attributes_os,
222 static struct attribute *ad7606_attributes_range[] = {
223 &iio_dev_attr_in_voltage_range.dev_attr.attr,
224 &iio_const_attr_in_voltage_range_available.dev_attr.attr,
228 static const struct attribute_group ad7606_attribute_group_range = {
229 .attrs = ad7606_attributes_range,
232 #define AD7606_CHANNEL(num) \
234 .type = IIO_VOLTAGE, \
238 .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT, \
240 .scan_type = IIO_ST('s', 16, 16, 0), \
243 static struct iio_chan_spec ad7606_8_channels[] = {
252 IIO_CHAN_SOFT_TIMESTAMP(8),
255 static struct iio_chan_spec ad7606_6_channels[] = {
262 IIO_CHAN_SOFT_TIMESTAMP(6),
265 static struct iio_chan_spec ad7606_4_channels[] = {
270 IIO_CHAN_SOFT_TIMESTAMP(4),
273 static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
275 * More devices added in future
280 .channels = ad7606_8_channels,
286 .channels = ad7606_6_channels,
292 .channels = ad7606_4_channels,
297 static int ad7606_request_gpios(struct ad7606_state *st)
299 struct gpio gpio_array[3] = {
301 .gpio = st->pdata->gpio_os0,
302 .flags = GPIOF_DIR_OUT | ((st->oversampling & 1) ?
303 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
304 .label = "AD7606_OS0",
307 .gpio = st->pdata->gpio_os1,
308 .flags = GPIOF_DIR_OUT | ((st->oversampling & 2) ?
309 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
310 .label = "AD7606_OS1",
313 .gpio = st->pdata->gpio_os2,
314 .flags = GPIOF_DIR_OUT | ((st->oversampling & 4) ?
315 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
316 .label = "AD7606_OS2",
321 if (gpio_is_valid(st->pdata->gpio_convst)) {
322 ret = gpio_request_one(st->pdata->gpio_convst,
326 dev_err(st->dev, "failed to request GPIO CONVST\n");
334 if (gpio_is_valid(st->pdata->gpio_os0) &&
335 gpio_is_valid(st->pdata->gpio_os1) &&
336 gpio_is_valid(st->pdata->gpio_os2)) {
337 ret = gpio_request_array(gpio_array, ARRAY_SIZE(gpio_array));
339 goto error_free_convst;
342 if (gpio_is_valid(st->pdata->gpio_reset)) {
343 ret = gpio_request_one(st->pdata->gpio_reset,
350 if (gpio_is_valid(st->pdata->gpio_range)) {
351 ret = gpio_request_one(st->pdata->gpio_range, GPIOF_DIR_OUT |
352 ((st->range == 10000) ? GPIOF_INIT_HIGH :
353 GPIOF_INIT_LOW), "AD7606_RANGE");
355 goto error_free_reset;
357 if (gpio_is_valid(st->pdata->gpio_stby)) {
358 ret = gpio_request_one(st->pdata->gpio_stby,
362 goto error_free_range;
365 if (gpio_is_valid(st->pdata->gpio_frstdata)) {
366 ret = gpio_request_one(st->pdata->gpio_frstdata, GPIOF_IN,
369 goto error_free_stby;
375 if (gpio_is_valid(st->pdata->gpio_stby))
376 gpio_free(st->pdata->gpio_stby);
378 if (gpio_is_valid(st->pdata->gpio_range))
379 gpio_free(st->pdata->gpio_range);
381 if (gpio_is_valid(st->pdata->gpio_reset))
382 gpio_free(st->pdata->gpio_reset);
384 if (gpio_is_valid(st->pdata->gpio_os0) &&
385 gpio_is_valid(st->pdata->gpio_os1) &&
386 gpio_is_valid(st->pdata->gpio_os2))
387 gpio_free_array(gpio_array, ARRAY_SIZE(gpio_array));
389 gpio_free(st->pdata->gpio_convst);
394 static void ad7606_free_gpios(struct ad7606_state *st)
396 if (gpio_is_valid(st->pdata->gpio_frstdata))
397 gpio_free(st->pdata->gpio_frstdata);
398 if (gpio_is_valid(st->pdata->gpio_stby))
399 gpio_free(st->pdata->gpio_stby);
400 if (gpio_is_valid(st->pdata->gpio_range))
401 gpio_free(st->pdata->gpio_range);
402 if (gpio_is_valid(st->pdata->gpio_reset))
403 gpio_free(st->pdata->gpio_reset);
404 if (gpio_is_valid(st->pdata->gpio_os0) &&
405 gpio_is_valid(st->pdata->gpio_os1) &&
406 gpio_is_valid(st->pdata->gpio_os2)) {
407 gpio_free(st->pdata->gpio_os2);
408 gpio_free(st->pdata->gpio_os1);
409 gpio_free(st->pdata->gpio_os0);
411 gpio_free(st->pdata->gpio_convst);
417 static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
419 struct iio_dev *indio_dev = dev_id;
420 struct ad7606_state *st = iio_priv(indio_dev);
422 if (iio_buffer_enabled(indio_dev)) {
423 if (!work_pending(&st->poll_work))
424 schedule_work(&st->poll_work);
427 wake_up_interruptible(&st->wq_data_avail);
433 static const struct iio_info ad7606_info_no_os_or_range = {
434 .driver_module = THIS_MODULE,
435 .read_raw = &ad7606_read_raw,
438 static const struct iio_info ad7606_info_os_and_range = {
439 .driver_module = THIS_MODULE,
440 .read_raw = &ad7606_read_raw,
441 .attrs = &ad7606_attribute_group_os_and_range,
444 static const struct iio_info ad7606_info_os = {
445 .driver_module = THIS_MODULE,
446 .read_raw = &ad7606_read_raw,
447 .attrs = &ad7606_attribute_group_os,
450 static const struct iio_info ad7606_info_range = {
451 .driver_module = THIS_MODULE,
452 .read_raw = &ad7606_read_raw,
453 .attrs = &ad7606_attribute_group_range,
456 struct iio_dev *ad7606_probe(struct device *dev, int irq,
457 void __iomem *base_address,
459 const struct ad7606_bus_ops *bops)
461 struct ad7606_platform_data *pdata = dev->platform_data;
462 struct ad7606_state *st;
464 struct iio_dev *indio_dev = iio_device_alloc(sizeof(*st));
466 if (indio_dev == NULL) {
471 st = iio_priv(indio_dev);
475 st->base_address = base_address;
476 st->range = pdata->default_range == 10000 ? 10000 : 5000;
478 ret = ad7606_oversampling_get_index(pdata->default_os);
480 dev_warn(dev, "oversampling %d is not supported\n",
482 st->oversampling = 0;
484 st->oversampling = pdata->default_os;
487 st->reg = regulator_get(dev, "vcc");
488 if (!IS_ERR(st->reg)) {
489 ret = regulator_enable(st->reg);
495 st->chip_info = &ad7606_chip_info_tbl[id];
497 indio_dev->dev.parent = dev;
498 if (gpio_is_valid(st->pdata->gpio_os0) &&
499 gpio_is_valid(st->pdata->gpio_os1) &&
500 gpio_is_valid(st->pdata->gpio_os2)) {
501 if (gpio_is_valid(st->pdata->gpio_range))
502 indio_dev->info = &ad7606_info_os_and_range;
504 indio_dev->info = &ad7606_info_os;
506 if (gpio_is_valid(st->pdata->gpio_range))
507 indio_dev->info = &ad7606_info_range;
509 indio_dev->info = &ad7606_info_no_os_or_range;
511 indio_dev->modes = INDIO_DIRECT_MODE;
512 indio_dev->name = st->chip_info->name;
513 indio_dev->channels = st->chip_info->channels;
514 indio_dev->num_channels = st->chip_info->num_channels;
516 init_waitqueue_head(&st->wq_data_avail);
518 ret = ad7606_request_gpios(st);
520 goto error_disable_reg;
522 ret = ad7606_reset(st);
524 dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
526 ret = request_irq(irq, ad7606_interrupt,
527 IRQF_TRIGGER_FALLING, st->chip_info->name, indio_dev);
529 goto error_free_gpios;
531 ret = ad7606_register_ring_funcs_and_init(indio_dev);
535 ret = iio_buffer_register(indio_dev,
537 indio_dev->num_channels);
539 goto error_cleanup_ring;
540 ret = iio_device_register(indio_dev);
542 goto error_unregister_ring;
545 error_unregister_ring:
546 iio_buffer_unregister(indio_dev);
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);
561 if (!IS_ERR(st->reg))
562 regulator_put(st->reg);
563 iio_device_free(indio_dev);
568 int ad7606_remove(struct iio_dev *indio_dev, int irq)
570 struct ad7606_state *st = iio_priv(indio_dev);
572 iio_device_unregister(indio_dev);
573 iio_buffer_unregister(indio_dev);
574 ad7606_ring_cleanup(indio_dev);
576 free_irq(irq, indio_dev);
577 if (!IS_ERR(st->reg)) {
578 regulator_disable(st->reg);
579 regulator_put(st->reg);
582 ad7606_free_gpios(st);
583 iio_device_free(indio_dev);
588 void ad7606_suspend(struct iio_dev *indio_dev)
590 struct ad7606_state *st = iio_priv(indio_dev);
592 if (gpio_is_valid(st->pdata->gpio_stby)) {
593 if (gpio_is_valid(st->pdata->gpio_range))
594 gpio_set_value(st->pdata->gpio_range, 1);
595 gpio_set_value(st->pdata->gpio_stby, 0);
599 void ad7606_resume(struct iio_dev *indio_dev)
601 struct ad7606_state *st = iio_priv(indio_dev);
603 if (gpio_is_valid(st->pdata->gpio_stby)) {
604 if (gpio_is_valid(st->pdata->gpio_range))
605 gpio_set_value(st->pdata->gpio_range,
608 gpio_set_value(st->pdata->gpio_stby, 1);
613 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
614 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
615 MODULE_LICENSE("GPL v2");