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);
130 ret = kstrtoul(buf, 10, &lval);
134 if (!(lval == 5000 || lval == 10000)) {
135 dev_err(dev, "range is not supported\n");
138 mutex_lock(&indio_dev->mlock);
139 gpio_set_value(st->pdata->gpio_range, lval == 10000);
141 mutex_unlock(&indio_dev->mlock);
146 static IIO_DEVICE_ATTR(in_voltage_range, S_IRUGO | S_IWUSR, \
147 ad7606_show_range, ad7606_store_range, 0);
148 static IIO_CONST_ATTR(in_voltage_range_available, "5000 10000");
150 static ssize_t ad7606_show_oversampling_ratio(struct device *dev,
151 struct device_attribute *attr, char *buf)
153 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
154 struct ad7606_state *st = iio_priv(indio_dev);
156 return sprintf(buf, "%u\n", st->oversampling);
159 static int ad7606_oversampling_get_index(unsigned val)
161 unsigned char supported[] = {0, 2, 4, 8, 16, 32, 64};
164 for (i = 0; i < ARRAY_SIZE(supported); i++)
165 if (val == supported[i])
171 static ssize_t ad7606_store_oversampling_ratio(struct device *dev,
172 struct device_attribute *attr, const char *buf, size_t count)
174 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
175 struct ad7606_state *st = iio_priv(indio_dev);
179 ret = kstrtoul(buf, 10, &lval);
183 ret = ad7606_oversampling_get_index(lval);
185 dev_err(dev, "oversampling %lu is not supported\n", lval);
189 mutex_lock(&indio_dev->mlock);
190 gpio_set_value(st->pdata->gpio_os0, (ret >> 0) & 1);
191 gpio_set_value(st->pdata->gpio_os1, (ret >> 1) & 1);
192 gpio_set_value(st->pdata->gpio_os1, (ret >> 2) & 1);
193 st->oversampling = lval;
194 mutex_unlock(&indio_dev->mlock);
199 static IIO_DEVICE_ATTR(oversampling_ratio, S_IRUGO | S_IWUSR,
200 ad7606_show_oversampling_ratio,
201 ad7606_store_oversampling_ratio, 0);
202 static IIO_CONST_ATTR(oversampling_ratio_available, "0 2 4 8 16 32 64");
204 static struct attribute *ad7606_attributes_os_and_range[] = {
205 &iio_dev_attr_in_voltage_range.dev_attr.attr,
206 &iio_const_attr_in_voltage_range_available.dev_attr.attr,
207 &iio_dev_attr_oversampling_ratio.dev_attr.attr,
208 &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
212 static const struct attribute_group ad7606_attribute_group_os_and_range = {
213 .attrs = ad7606_attributes_os_and_range,
216 static struct attribute *ad7606_attributes_os[] = {
217 &iio_dev_attr_oversampling_ratio.dev_attr.attr,
218 &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
222 static const struct attribute_group ad7606_attribute_group_os = {
223 .attrs = ad7606_attributes_os,
226 static struct attribute *ad7606_attributes_range[] = {
227 &iio_dev_attr_in_voltage_range.dev_attr.attr,
228 &iio_const_attr_in_voltage_range_available.dev_attr.attr,
232 static const struct attribute_group ad7606_attribute_group_range = {
233 .attrs = ad7606_attributes_range,
236 #define AD7606_CHANNEL(num) \
238 .type = IIO_VOLTAGE, \
242 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
243 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
245 .scan_type = IIO_ST('s', 16, 16, 0), \
248 static const struct iio_chan_spec ad7606_8_channels[] = {
257 IIO_CHAN_SOFT_TIMESTAMP(8),
260 static const struct iio_chan_spec ad7606_6_channels[] = {
267 IIO_CHAN_SOFT_TIMESTAMP(6),
270 static const struct iio_chan_spec ad7606_4_channels[] = {
275 IIO_CHAN_SOFT_TIMESTAMP(4),
278 static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
280 * More devices added in future
285 .channels = ad7606_8_channels,
291 .channels = ad7606_6_channels,
297 .channels = ad7606_4_channels,
302 static int ad7606_request_gpios(struct ad7606_state *st)
304 struct gpio gpio_array[3] = {
306 .gpio = st->pdata->gpio_os0,
307 .flags = GPIOF_DIR_OUT | ((st->oversampling & 1) ?
308 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
309 .label = "AD7606_OS0",
312 .gpio = st->pdata->gpio_os1,
313 .flags = GPIOF_DIR_OUT | ((st->oversampling & 2) ?
314 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
315 .label = "AD7606_OS1",
318 .gpio = st->pdata->gpio_os2,
319 .flags = GPIOF_DIR_OUT | ((st->oversampling & 4) ?
320 GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
321 .label = "AD7606_OS2",
326 if (gpio_is_valid(st->pdata->gpio_convst)) {
327 ret = gpio_request_one(st->pdata->gpio_convst,
331 dev_err(st->dev, "failed to request GPIO CONVST\n");
339 if (gpio_is_valid(st->pdata->gpio_os0) &&
340 gpio_is_valid(st->pdata->gpio_os1) &&
341 gpio_is_valid(st->pdata->gpio_os2)) {
342 ret = gpio_request_array(gpio_array, ARRAY_SIZE(gpio_array));
344 goto error_free_convst;
347 if (gpio_is_valid(st->pdata->gpio_reset)) {
348 ret = gpio_request_one(st->pdata->gpio_reset,
355 if (gpio_is_valid(st->pdata->gpio_range)) {
356 ret = gpio_request_one(st->pdata->gpio_range, GPIOF_DIR_OUT |
357 ((st->range == 10000) ? GPIOF_INIT_HIGH :
358 GPIOF_INIT_LOW), "AD7606_RANGE");
360 goto error_free_reset;
362 if (gpio_is_valid(st->pdata->gpio_stby)) {
363 ret = gpio_request_one(st->pdata->gpio_stby,
367 goto error_free_range;
370 if (gpio_is_valid(st->pdata->gpio_frstdata)) {
371 ret = gpio_request_one(st->pdata->gpio_frstdata, GPIOF_IN,
374 goto error_free_stby;
380 if (gpio_is_valid(st->pdata->gpio_stby))
381 gpio_free(st->pdata->gpio_stby);
383 if (gpio_is_valid(st->pdata->gpio_range))
384 gpio_free(st->pdata->gpio_range);
386 if (gpio_is_valid(st->pdata->gpio_reset))
387 gpio_free(st->pdata->gpio_reset);
389 if (gpio_is_valid(st->pdata->gpio_os0) &&
390 gpio_is_valid(st->pdata->gpio_os1) &&
391 gpio_is_valid(st->pdata->gpio_os2))
392 gpio_free_array(gpio_array, ARRAY_SIZE(gpio_array));
394 gpio_free(st->pdata->gpio_convst);
399 static void ad7606_free_gpios(struct ad7606_state *st)
401 if (gpio_is_valid(st->pdata->gpio_frstdata))
402 gpio_free(st->pdata->gpio_frstdata);
403 if (gpio_is_valid(st->pdata->gpio_stby))
404 gpio_free(st->pdata->gpio_stby);
405 if (gpio_is_valid(st->pdata->gpio_range))
406 gpio_free(st->pdata->gpio_range);
407 if (gpio_is_valid(st->pdata->gpio_reset))
408 gpio_free(st->pdata->gpio_reset);
409 if (gpio_is_valid(st->pdata->gpio_os0) &&
410 gpio_is_valid(st->pdata->gpio_os1) &&
411 gpio_is_valid(st->pdata->gpio_os2)) {
412 gpio_free(st->pdata->gpio_os2);
413 gpio_free(st->pdata->gpio_os1);
414 gpio_free(st->pdata->gpio_os0);
416 gpio_free(st->pdata->gpio_convst);
422 static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
424 struct iio_dev *indio_dev = dev_id;
425 struct ad7606_state *st = iio_priv(indio_dev);
427 if (iio_buffer_enabled(indio_dev)) {
428 if (!work_pending(&st->poll_work))
429 schedule_work(&st->poll_work);
432 wake_up_interruptible(&st->wq_data_avail);
438 static const struct iio_info ad7606_info_no_os_or_range = {
439 .driver_module = THIS_MODULE,
440 .read_raw = &ad7606_read_raw,
443 static const struct iio_info ad7606_info_os_and_range = {
444 .driver_module = THIS_MODULE,
445 .read_raw = &ad7606_read_raw,
446 .attrs = &ad7606_attribute_group_os_and_range,
449 static const struct iio_info ad7606_info_os = {
450 .driver_module = THIS_MODULE,
451 .read_raw = &ad7606_read_raw,
452 .attrs = &ad7606_attribute_group_os,
455 static const struct iio_info ad7606_info_range = {
456 .driver_module = THIS_MODULE,
457 .read_raw = &ad7606_read_raw,
458 .attrs = &ad7606_attribute_group_range,
461 struct iio_dev *ad7606_probe(struct device *dev, int irq,
462 void __iomem *base_address,
464 const struct ad7606_bus_ops *bops)
466 struct ad7606_platform_data *pdata = dev->platform_data;
467 struct ad7606_state *st;
469 struct iio_dev *indio_dev = iio_device_alloc(sizeof(*st));
471 if (indio_dev == NULL) {
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 = 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);
558 if (!IS_ERR(st->reg))
559 regulator_put(st->reg);
560 iio_device_free(indio_dev);
565 int ad7606_remove(struct iio_dev *indio_dev, int irq)
567 struct ad7606_state *st = iio_priv(indio_dev);
569 iio_device_unregister(indio_dev);
570 ad7606_ring_cleanup(indio_dev);
572 free_irq(irq, indio_dev);
573 if (!IS_ERR(st->reg)) {
574 regulator_disable(st->reg);
575 regulator_put(st->reg);
578 ad7606_free_gpios(st);
579 iio_device_free(indio_dev);
584 void ad7606_suspend(struct iio_dev *indio_dev)
586 struct ad7606_state *st = iio_priv(indio_dev);
588 if (gpio_is_valid(st->pdata->gpio_stby)) {
589 if (gpio_is_valid(st->pdata->gpio_range))
590 gpio_set_value(st->pdata->gpio_range, 1);
591 gpio_set_value(st->pdata->gpio_stby, 0);
595 void ad7606_resume(struct iio_dev *indio_dev)
597 struct ad7606_state *st = iio_priv(indio_dev);
599 if (gpio_is_valid(st->pdata->gpio_stby)) {
600 if (gpio_is_valid(st->pdata->gpio_range))
601 gpio_set_value(st->pdata->gpio_range,
604 gpio_set_value(st->pdata->gpio_stby, 1);
609 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
610 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
611 MODULE_LICENSE("GPL v2");