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_separate = BIT(IIO_CHAN_INFO_RAW), \
239 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
241 .scan_type = IIO_ST('s', 16, 16, 0), \
244 static const struct iio_chan_spec ad7606_8_channels[] = {
253 IIO_CHAN_SOFT_TIMESTAMP(8),
256 static const struct iio_chan_spec ad7606_6_channels[] = {
263 IIO_CHAN_SOFT_TIMESTAMP(6),
266 static const struct iio_chan_spec ad7606_4_channels[] = {
271 IIO_CHAN_SOFT_TIMESTAMP(4),
274 static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
276 * More devices added in future
281 .channels = ad7606_8_channels,
287 .channels = ad7606_6_channels,
293 .channels = ad7606_4_channels,
298 static int ad7606_request_gpios(struct ad7606_state *st)
300 struct gpio gpio_array[3] = {
302 .gpio = st->pdata->gpio_os0,
303 .flags = GPIOF_DIR_OUT | ((st->oversampling & 1) ?
304 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
305 .label = "AD7606_OS0",
308 .gpio = st->pdata->gpio_os1,
309 .flags = GPIOF_DIR_OUT | ((st->oversampling & 2) ?
310 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
311 .label = "AD7606_OS1",
314 .gpio = st->pdata->gpio_os2,
315 .flags = GPIOF_DIR_OUT | ((st->oversampling & 4) ?
316 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
317 .label = "AD7606_OS2",
322 if (gpio_is_valid(st->pdata->gpio_convst)) {
323 ret = gpio_request_one(st->pdata->gpio_convst,
327 dev_err(st->dev, "failed to request GPIO CONVST\n");
335 if (gpio_is_valid(st->pdata->gpio_os0) &&
336 gpio_is_valid(st->pdata->gpio_os1) &&
337 gpio_is_valid(st->pdata->gpio_os2)) {
338 ret = gpio_request_array(gpio_array, ARRAY_SIZE(gpio_array));
340 goto error_free_convst;
343 if (gpio_is_valid(st->pdata->gpio_reset)) {
344 ret = gpio_request_one(st->pdata->gpio_reset,
351 if (gpio_is_valid(st->pdata->gpio_range)) {
352 ret = gpio_request_one(st->pdata->gpio_range, GPIOF_DIR_OUT |
353 ((st->range == 10000) ? GPIOF_INIT_HIGH :
354 GPIOF_INIT_LOW), "AD7606_RANGE");
356 goto error_free_reset;
358 if (gpio_is_valid(st->pdata->gpio_stby)) {
359 ret = gpio_request_one(st->pdata->gpio_stby,
363 goto error_free_range;
366 if (gpio_is_valid(st->pdata->gpio_frstdata)) {
367 ret = gpio_request_one(st->pdata->gpio_frstdata, GPIOF_IN,
370 goto error_free_stby;
376 if (gpio_is_valid(st->pdata->gpio_stby))
377 gpio_free(st->pdata->gpio_stby);
379 if (gpio_is_valid(st->pdata->gpio_range))
380 gpio_free(st->pdata->gpio_range);
382 if (gpio_is_valid(st->pdata->gpio_reset))
383 gpio_free(st->pdata->gpio_reset);
385 if (gpio_is_valid(st->pdata->gpio_os0) &&
386 gpio_is_valid(st->pdata->gpio_os1) &&
387 gpio_is_valid(st->pdata->gpio_os2))
388 gpio_free_array(gpio_array, ARRAY_SIZE(gpio_array));
390 gpio_free(st->pdata->gpio_convst);
395 static void ad7606_free_gpios(struct ad7606_state *st)
397 if (gpio_is_valid(st->pdata->gpio_frstdata))
398 gpio_free(st->pdata->gpio_frstdata);
399 if (gpio_is_valid(st->pdata->gpio_stby))
400 gpio_free(st->pdata->gpio_stby);
401 if (gpio_is_valid(st->pdata->gpio_range))
402 gpio_free(st->pdata->gpio_range);
403 if (gpio_is_valid(st->pdata->gpio_reset))
404 gpio_free(st->pdata->gpio_reset);
405 if (gpio_is_valid(st->pdata->gpio_os0) &&
406 gpio_is_valid(st->pdata->gpio_os1) &&
407 gpio_is_valid(st->pdata->gpio_os2)) {
408 gpio_free(st->pdata->gpio_os2);
409 gpio_free(st->pdata->gpio_os1);
410 gpio_free(st->pdata->gpio_os0);
412 gpio_free(st->pdata->gpio_convst);
418 static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
420 struct iio_dev *indio_dev = dev_id;
421 struct ad7606_state *st = iio_priv(indio_dev);
423 if (iio_buffer_enabled(indio_dev)) {
424 if (!work_pending(&st->poll_work))
425 schedule_work(&st->poll_work);
428 wake_up_interruptible(&st->wq_data_avail);
434 static const struct iio_info ad7606_info_no_os_or_range = {
435 .driver_module = THIS_MODULE,
436 .read_raw = &ad7606_read_raw,
439 static const struct iio_info ad7606_info_os_and_range = {
440 .driver_module = THIS_MODULE,
441 .read_raw = &ad7606_read_raw,
442 .attrs = &ad7606_attribute_group_os_and_range,
445 static const struct iio_info ad7606_info_os = {
446 .driver_module = THIS_MODULE,
447 .read_raw = &ad7606_read_raw,
448 .attrs = &ad7606_attribute_group_os,
451 static const struct iio_info ad7606_info_range = {
452 .driver_module = THIS_MODULE,
453 .read_raw = &ad7606_read_raw,
454 .attrs = &ad7606_attribute_group_range,
457 struct iio_dev *ad7606_probe(struct device *dev, int irq,
458 void __iomem *base_address,
460 const struct ad7606_bus_ops *bops)
462 struct ad7606_platform_data *pdata = dev->platform_data;
463 struct ad7606_state *st;
465 struct iio_dev *indio_dev = iio_device_alloc(sizeof(*st));
467 if (indio_dev == NULL) {
472 st = iio_priv(indio_dev);
476 st->base_address = base_address;
477 st->range = pdata->default_range == 10000 ? 10000 : 5000;
479 ret = ad7606_oversampling_get_index(pdata->default_os);
481 dev_warn(dev, "oversampling %d is not supported\n",
483 st->oversampling = 0;
485 st->oversampling = pdata->default_os;
488 st->reg = regulator_get(dev, "vcc");
489 if (!IS_ERR(st->reg)) {
490 ret = regulator_enable(st->reg);
496 st->chip_info = &ad7606_chip_info_tbl[id];
498 indio_dev->dev.parent = dev;
499 if (gpio_is_valid(st->pdata->gpio_os0) &&
500 gpio_is_valid(st->pdata->gpio_os1) &&
501 gpio_is_valid(st->pdata->gpio_os2)) {
502 if (gpio_is_valid(st->pdata->gpio_range))
503 indio_dev->info = &ad7606_info_os_and_range;
505 indio_dev->info = &ad7606_info_os;
507 if (gpio_is_valid(st->pdata->gpio_range))
508 indio_dev->info = &ad7606_info_range;
510 indio_dev->info = &ad7606_info_no_os_or_range;
512 indio_dev->modes = INDIO_DIRECT_MODE;
513 indio_dev->name = st->chip_info->name;
514 indio_dev->channels = st->chip_info->channels;
515 indio_dev->num_channels = st->chip_info->num_channels;
517 init_waitqueue_head(&st->wq_data_avail);
519 ret = ad7606_request_gpios(st);
521 goto error_disable_reg;
523 ret = ad7606_reset(st);
525 dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
527 ret = request_irq(irq, ad7606_interrupt,
528 IRQF_TRIGGER_FALLING, st->chip_info->name, indio_dev);
530 goto error_free_gpios;
532 ret = ad7606_register_ring_funcs_and_init(indio_dev);
536 ret = iio_device_register(indio_dev);
538 goto error_unregister_ring;
541 error_unregister_ring:
542 ad7606_ring_cleanup(indio_dev);
545 free_irq(irq, indio_dev);
548 ad7606_free_gpios(st);
551 if (!IS_ERR(st->reg))
552 regulator_disable(st->reg);
554 if (!IS_ERR(st->reg))
555 regulator_put(st->reg);
556 iio_device_free(indio_dev);
561 int ad7606_remove(struct iio_dev *indio_dev, int irq)
563 struct ad7606_state *st = iio_priv(indio_dev);
565 iio_device_unregister(indio_dev);
566 ad7606_ring_cleanup(indio_dev);
568 free_irq(irq, indio_dev);
569 if (!IS_ERR(st->reg)) {
570 regulator_disable(st->reg);
571 regulator_put(st->reg);
574 ad7606_free_gpios(st);
575 iio_device_free(indio_dev);
580 void ad7606_suspend(struct iio_dev *indio_dev)
582 struct ad7606_state *st = iio_priv(indio_dev);
584 if (gpio_is_valid(st->pdata->gpio_stby)) {
585 if (gpio_is_valid(st->pdata->gpio_range))
586 gpio_set_value(st->pdata->gpio_range, 1);
587 gpio_set_value(st->pdata->gpio_stby, 0);
591 void ad7606_resume(struct iio_dev *indio_dev)
593 struct ad7606_state *st = iio_priv(indio_dev);
595 if (gpio_is_valid(st->pdata->gpio_stby)) {
596 if (gpio_is_valid(st->pdata->gpio_range))
597 gpio_set_value(st->pdata->gpio_range,
600 gpio_set_value(st->pdata->gpio_stby, 1);
605 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
606 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
607 MODULE_LICENSE("GPL v2");