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.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 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_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_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[] = {
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, \
245 .scan_type = IIO_ST('s', 16, 16, 0), \
248 static struct iio_chan_spec ad7606_8_channels[] = {
257 IIO_CHAN_SOFT_TIMESTAMP(8),
260 static struct iio_chan_spec ad7606_6_channels[] = {
267 IIO_CHAN_SOFT_TIMESTAMP(6),
270 static 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 = {
439 .driver_module = THIS_MODULE,
440 .read_raw = &ad7606_read_raw,
441 .attrs = &ad7606_attribute_group,
444 struct iio_dev *ad7606_probe(struct device *dev, int irq,
445 void __iomem *base_address,
447 const struct ad7606_bus_ops *bops)
449 struct ad7606_platform_data *pdata = dev->platform_data;
450 struct ad7606_state *st;
452 struct iio_dev *indio_dev = iio_allocate_device(sizeof(*st));
454 if (indio_dev == NULL) {
459 st = iio_priv(indio_dev);
463 st->base_address = base_address;
464 st->range = pdata->default_range == 10000 ? 10000 : 5000;
466 ret = ad7606_oversampling_get_index(pdata->default_os);
468 dev_warn(dev, "oversampling %d is not supported\n",
470 st->oversampling = 0;
472 st->oversampling = pdata->default_os;
475 st->reg = regulator_get(dev, "vcc");
476 if (!IS_ERR(st->reg)) {
477 ret = regulator_enable(st->reg);
483 st->chip_info = &ad7606_chip_info_tbl[id];
485 indio_dev->dev.parent = dev;
486 indio_dev->info = &ad7606_info;
487 indio_dev->modes = INDIO_DIRECT_MODE;
488 indio_dev->name = st->chip_info->name;
489 indio_dev->channels = st->chip_info->channels;
490 indio_dev->num_channels = st->chip_info->num_channels;
492 init_waitqueue_head(&st->wq_data_avail);
494 ret = ad7606_request_gpios(st);
496 goto error_disable_reg;
498 ret = ad7606_reset(st);
500 dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
502 ret = request_irq(irq, ad7606_interrupt,
503 IRQF_TRIGGER_FALLING, st->chip_info->name, indio_dev);
505 goto error_free_gpios;
507 ret = ad7606_register_ring_funcs_and_init(indio_dev);
511 ret = iio_buffer_register(indio_dev,
513 indio_dev->num_channels);
515 goto error_cleanup_ring;
516 ret = iio_device_register(indio_dev);
518 goto error_unregister_ring;
521 error_unregister_ring:
522 iio_buffer_unregister(indio_dev);
525 ad7606_ring_cleanup(indio_dev);
528 free_irq(irq, indio_dev);
531 ad7606_free_gpios(st);
534 if (!IS_ERR(st->reg))
535 regulator_disable(st->reg);
537 if (!IS_ERR(st->reg))
538 regulator_put(st->reg);
539 iio_free_device(indio_dev);
544 int ad7606_remove(struct iio_dev *indio_dev, int irq)
546 struct ad7606_state *st = iio_priv(indio_dev);
548 iio_device_unregister(indio_dev);
549 iio_buffer_unregister(indio_dev);
550 ad7606_ring_cleanup(indio_dev);
552 free_irq(irq, indio_dev);
553 if (!IS_ERR(st->reg)) {
554 regulator_disable(st->reg);
555 regulator_put(st->reg);
558 ad7606_free_gpios(st);
559 iio_free_device(indio_dev);
564 void ad7606_suspend(struct iio_dev *indio_dev)
566 struct ad7606_state *st = iio_priv(indio_dev);
568 if (gpio_is_valid(st->pdata->gpio_stby)) {
569 if (gpio_is_valid(st->pdata->gpio_range))
570 gpio_set_value(st->pdata->gpio_range, 1);
571 gpio_set_value(st->pdata->gpio_stby, 0);
575 void ad7606_resume(struct iio_dev *indio_dev)
577 struct ad7606_state *st = iio_priv(indio_dev);
579 if (gpio_is_valid(st->pdata->gpio_stby)) {
580 if (gpio_is_valid(st->pdata->gpio_range))
581 gpio_set_value(st->pdata->gpio_range,
584 gpio_set_value(st->pdata->gpio_stby, 1);
589 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
590 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
591 MODULE_LICENSE("GPL v2");