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, const char *buf, size_t count)
122 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
123 struct ad7606_state *st = iio_priv(indio_dev);
127 ret = kstrtoul(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 ret = kstrtoul(buf, 10, &lval);
180 ret = ad7606_oversampling_get_index(lval);
182 dev_err(dev, "oversampling %lu is not supported\n", lval);
186 mutex_lock(&indio_dev->mlock);
187 gpio_set_value(st->pdata->gpio_os0, (ret >> 0) & 1);
188 gpio_set_value(st->pdata->gpio_os1, (ret >> 1) & 1);
189 gpio_set_value(st->pdata->gpio_os1, (ret >> 2) & 1);
190 st->oversampling = lval;
191 mutex_unlock(&indio_dev->mlock);
196 static IIO_DEVICE_ATTR(oversampling_ratio, S_IRUGO | S_IWUSR,
197 ad7606_show_oversampling_ratio,
198 ad7606_store_oversampling_ratio, 0);
199 static IIO_CONST_ATTR(oversampling_ratio_available, "0 2 4 8 16 32 64");
201 static struct attribute *ad7606_attributes_os_and_range[] = {
202 &iio_dev_attr_in_voltage_range.dev_attr.attr,
203 &iio_const_attr_in_voltage_range_available.dev_attr.attr,
204 &iio_dev_attr_oversampling_ratio.dev_attr.attr,
205 &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
209 static const struct attribute_group ad7606_attribute_group_os_and_range = {
210 .attrs = ad7606_attributes_os_and_range,
213 static struct attribute *ad7606_attributes_os[] = {
214 &iio_dev_attr_oversampling_ratio.dev_attr.attr,
215 &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
219 static const struct attribute_group ad7606_attribute_group_os = {
220 .attrs = ad7606_attributes_os,
223 static struct attribute *ad7606_attributes_range[] = {
224 &iio_dev_attr_in_voltage_range.dev_attr.attr,
225 &iio_const_attr_in_voltage_range_available.dev_attr.attr,
229 static const struct attribute_group ad7606_attribute_group_range = {
230 .attrs = ad7606_attributes_range,
233 #define AD7606_CHANNEL(num) \
235 .type = IIO_VOLTAGE, \
239 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
240 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
246 .endianness = IIO_CPU, \
250 static const struct iio_chan_spec ad7606_8_channels[] = {
259 IIO_CHAN_SOFT_TIMESTAMP(8),
262 static const struct iio_chan_spec ad7606_6_channels[] = {
269 IIO_CHAN_SOFT_TIMESTAMP(6),
272 static const struct iio_chan_spec ad7606_4_channels[] = {
277 IIO_CHAN_SOFT_TIMESTAMP(4),
280 static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
282 * More devices added in future
287 .channels = ad7606_8_channels,
293 .channels = ad7606_6_channels,
299 .channels = ad7606_4_channels,
304 static int ad7606_request_gpios(struct ad7606_state *st)
306 struct gpio gpio_array[3] = {
308 .gpio = st->pdata->gpio_os0,
309 .flags = GPIOF_DIR_OUT | ((st->oversampling & 1) ?
310 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
311 .label = "AD7606_OS0",
314 .gpio = st->pdata->gpio_os1,
315 .flags = GPIOF_DIR_OUT | ((st->oversampling & 2) ?
316 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
317 .label = "AD7606_OS1",
320 .gpio = st->pdata->gpio_os2,
321 .flags = GPIOF_DIR_OUT | ((st->oversampling & 4) ?
322 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
323 .label = "AD7606_OS2",
328 if (gpio_is_valid(st->pdata->gpio_convst)) {
329 ret = gpio_request_one(st->pdata->gpio_convst,
333 dev_err(st->dev, "failed to request GPIO CONVST\n");
341 if (gpio_is_valid(st->pdata->gpio_os0) &&
342 gpio_is_valid(st->pdata->gpio_os1) &&
343 gpio_is_valid(st->pdata->gpio_os2)) {
344 ret = gpio_request_array(gpio_array, ARRAY_SIZE(gpio_array));
346 goto error_free_convst;
349 if (gpio_is_valid(st->pdata->gpio_reset)) {
350 ret = gpio_request_one(st->pdata->gpio_reset,
357 if (gpio_is_valid(st->pdata->gpio_range)) {
358 ret = gpio_request_one(st->pdata->gpio_range, GPIOF_DIR_OUT |
359 ((st->range == 10000) ? GPIOF_INIT_HIGH :
360 GPIOF_INIT_LOW), "AD7606_RANGE");
362 goto error_free_reset;
364 if (gpio_is_valid(st->pdata->gpio_stby)) {
365 ret = gpio_request_one(st->pdata->gpio_stby,
369 goto error_free_range;
372 if (gpio_is_valid(st->pdata->gpio_frstdata)) {
373 ret = gpio_request_one(st->pdata->gpio_frstdata, GPIOF_IN,
376 goto error_free_stby;
382 if (gpio_is_valid(st->pdata->gpio_stby))
383 gpio_free(st->pdata->gpio_stby);
385 if (gpio_is_valid(st->pdata->gpio_range))
386 gpio_free(st->pdata->gpio_range);
388 if (gpio_is_valid(st->pdata->gpio_reset))
389 gpio_free(st->pdata->gpio_reset);
391 if (gpio_is_valid(st->pdata->gpio_os0) &&
392 gpio_is_valid(st->pdata->gpio_os1) &&
393 gpio_is_valid(st->pdata->gpio_os2))
394 gpio_free_array(gpio_array, ARRAY_SIZE(gpio_array));
396 gpio_free(st->pdata->gpio_convst);
401 static void ad7606_free_gpios(struct ad7606_state *st)
403 if (gpio_is_valid(st->pdata->gpio_frstdata))
404 gpio_free(st->pdata->gpio_frstdata);
405 if (gpio_is_valid(st->pdata->gpio_stby))
406 gpio_free(st->pdata->gpio_stby);
407 if (gpio_is_valid(st->pdata->gpio_range))
408 gpio_free(st->pdata->gpio_range);
409 if (gpio_is_valid(st->pdata->gpio_reset))
410 gpio_free(st->pdata->gpio_reset);
411 if (gpio_is_valid(st->pdata->gpio_os0) &&
412 gpio_is_valid(st->pdata->gpio_os1) &&
413 gpio_is_valid(st->pdata->gpio_os2)) {
414 gpio_free(st->pdata->gpio_os2);
415 gpio_free(st->pdata->gpio_os1);
416 gpio_free(st->pdata->gpio_os0);
418 gpio_free(st->pdata->gpio_convst);
424 static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
426 struct iio_dev *indio_dev = dev_id;
427 struct ad7606_state *st = iio_priv(indio_dev);
429 if (iio_buffer_enabled(indio_dev)) {
430 schedule_work(&st->poll_work);
433 wake_up_interruptible(&st->wq_data_avail);
439 static const struct iio_info ad7606_info_no_os_or_range = {
440 .driver_module = THIS_MODULE,
441 .read_raw = &ad7606_read_raw,
444 static const struct iio_info ad7606_info_os_and_range = {
445 .driver_module = THIS_MODULE,
446 .read_raw = &ad7606_read_raw,
447 .attrs = &ad7606_attribute_group_os_and_range,
450 static const struct iio_info ad7606_info_os = {
451 .driver_module = THIS_MODULE,
452 .read_raw = &ad7606_read_raw,
453 .attrs = &ad7606_attribute_group_os,
456 static const struct iio_info ad7606_info_range = {
457 .driver_module = THIS_MODULE,
458 .read_raw = &ad7606_read_raw,
459 .attrs = &ad7606_attribute_group_range,
462 struct iio_dev *ad7606_probe(struct device *dev, int irq,
463 void __iomem *base_address,
465 const struct ad7606_bus_ops *bops)
467 struct ad7606_platform_data *pdata = dev->platform_data;
468 struct ad7606_state *st;
470 struct iio_dev *indio_dev;
472 indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
474 return ERR_PTR(-ENOMEM);
476 st = iio_priv(indio_dev);
480 st->base_address = base_address;
481 st->range = pdata->default_range == 10000 ? 10000 : 5000;
483 ret = ad7606_oversampling_get_index(pdata->default_os);
485 dev_warn(dev, "oversampling %d is not supported\n",
487 st->oversampling = 0;
489 st->oversampling = pdata->default_os;
492 st->reg = devm_regulator_get(dev, "vcc");
493 if (!IS_ERR(st->reg)) {
494 ret = regulator_enable(st->reg);
500 st->chip_info = &ad7606_chip_info_tbl[id];
502 indio_dev->dev.parent = dev;
503 if (gpio_is_valid(st->pdata->gpio_os0) &&
504 gpio_is_valid(st->pdata->gpio_os1) &&
505 gpio_is_valid(st->pdata->gpio_os2)) {
506 if (gpio_is_valid(st->pdata->gpio_range))
507 indio_dev->info = &ad7606_info_os_and_range;
509 indio_dev->info = &ad7606_info_os;
511 if (gpio_is_valid(st->pdata->gpio_range))
512 indio_dev->info = &ad7606_info_range;
514 indio_dev->info = &ad7606_info_no_os_or_range;
516 indio_dev->modes = INDIO_DIRECT_MODE;
517 indio_dev->name = st->chip_info->name;
518 indio_dev->channels = st->chip_info->channels;
519 indio_dev->num_channels = st->chip_info->num_channels;
521 init_waitqueue_head(&st->wq_data_avail);
523 ret = ad7606_request_gpios(st);
525 goto error_disable_reg;
527 ret = ad7606_reset(st);
529 dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
531 ret = request_irq(irq, ad7606_interrupt,
532 IRQF_TRIGGER_FALLING, st->chip_info->name, indio_dev);
534 goto error_free_gpios;
536 ret = ad7606_register_ring_funcs_and_init(indio_dev);
540 ret = iio_device_register(indio_dev);
542 goto error_unregister_ring;
545 error_unregister_ring:
546 ad7606_ring_cleanup(indio_dev);
549 free_irq(irq, indio_dev);
552 ad7606_free_gpios(st);
555 if (!IS_ERR(st->reg))
556 regulator_disable(st->reg);
560 int ad7606_remove(struct iio_dev *indio_dev, int irq)
562 struct ad7606_state *st = iio_priv(indio_dev);
564 iio_device_unregister(indio_dev);
565 ad7606_ring_cleanup(indio_dev);
567 free_irq(irq, indio_dev);
568 if (!IS_ERR(st->reg))
569 regulator_disable(st->reg);
571 ad7606_free_gpios(st);
576 void ad7606_suspend(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, 1);
583 gpio_set_value(st->pdata->gpio_stby, 0);
587 void ad7606_resume(struct iio_dev *indio_dev)
589 struct ad7606_state *st = iio_priv(indio_dev);
591 if (gpio_is_valid(st->pdata->gpio_stby)) {
592 if (gpio_is_valid(st->pdata->gpio_range))
593 gpio_set_value(st->pdata->gpio_range,
596 gpio_set_value(st->pdata->gpio_stby, 1);
601 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
602 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
603 MODULE_LICENSE("GPL v2");