--- /dev/null
+/*
+ * AD7606 SPI ADC driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/regulator/consumer.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+
+#include "ad7606.h"
+
+int ad7606_reset(struct ad7606_state *st)
+{
+ if (gpio_is_valid(st->pdata->gpio_reset)) {
+ gpio_set_value(st->pdata->gpio_reset, 1);
+ ndelay(100); /* t_reset >= 100ns */
+ gpio_set_value(st->pdata->gpio_reset, 0);
+ return 0;
+ }
+
+ return -ENODEV;
+}
+
+static int ad7606_scan_direct(struct iio_dev *indio_dev, unsigned ch)
+{
+ struct ad7606_state *st = iio_priv(indio_dev);
+ int ret;
+
+ st->done = false;
+ gpio_set_value(st->pdata->gpio_convst, 1);
+
+ ret = wait_event_interruptible(st->wq_data_avail, st->done);
+ if (ret)
+ goto error_ret;
+
+ if (gpio_is_valid(st->pdata->gpio_frstdata)) {
+ ret = st->bops->read_block(st->dev, 1, st->data);
+ if (ret)
+ goto error_ret;
+ if (!gpio_get_value(st->pdata->gpio_frstdata)) {
+ /* This should never happen */
+ ad7606_reset(st);
+ ret = -EIO;
+ goto error_ret;
+ }
+ ret = st->bops->read_block(st->dev,
+ st->chip_info->num_channels - 1, &st->data[1]);
+ if (ret)
+ goto error_ret;
+ } else {
+ ret = st->bops->read_block(st->dev,
+ st->chip_info->num_channels, st->data);
+ if (ret)
+ goto error_ret;
+ }
+
+ ret = st->data[ch];
+
+error_ret:
+ gpio_set_value(st->pdata->gpio_convst, 0);
+
+ return ret;
+}
+
+static int ad7606_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long m)
+{
+ int ret;
+ struct ad7606_state *st = iio_priv(indio_dev);
+
+ switch (m) {
+ case IIO_CHAN_INFO_RAW:
+ mutex_lock(&indio_dev->mlock);
+ if (iio_buffer_enabled(indio_dev))
+ ret = -EBUSY;
+ else
+ ret = ad7606_scan_direct(indio_dev, chan->address);
+ mutex_unlock(&indio_dev->mlock);
+
+ if (ret < 0)
+ return ret;
+ *val = (short) ret;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = st->range * 2;
+ *val2 = st->chip_info->channels[0].scan_type.realbits;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ }
+ return -EINVAL;
+}
+
+static ssize_t ad7606_show_range(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct ad7606_state *st = iio_priv(indio_dev);
+
+ return sprintf(buf, "%u\n", st->range);
+}
+
+static ssize_t ad7606_store_range(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct ad7606_state *st = iio_priv(indio_dev);
+ unsigned long lval;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &lval);
+ if (ret)
+ return ret;
+
+ if (!(lval == 5000 || lval == 10000)) {
+ dev_err(dev, "range is not supported\n");
+ return -EINVAL;
+ }
+ mutex_lock(&indio_dev->mlock);
+ gpio_set_value(st->pdata->gpio_range, lval == 10000);
+ st->range = lval;
+ mutex_unlock(&indio_dev->mlock);
+
+ return count;
+}
+
+static IIO_DEVICE_ATTR(in_voltage_range, S_IRUGO | S_IWUSR,
+ ad7606_show_range, ad7606_store_range, 0);
+static IIO_CONST_ATTR(in_voltage_range_available, "5000 10000");
+
+static ssize_t ad7606_show_oversampling_ratio(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct ad7606_state *st = iio_priv(indio_dev);
+
+ return sprintf(buf, "%u\n", st->oversampling);
+}
+
+static int ad7606_oversampling_get_index(unsigned val)
+{
+ unsigned char supported[] = {0, 2, 4, 8, 16, 32, 64};
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(supported); i++)
+ if (val == supported[i])
+ return i;
+
+ return -EINVAL;
+}
+
+static ssize_t ad7606_store_oversampling_ratio(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct ad7606_state *st = iio_priv(indio_dev);
+ unsigned long lval;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &lval);
+ if (ret)
+ return ret;
+
+ ret = ad7606_oversampling_get_index(lval);
+ if (ret < 0) {
+ dev_err(dev, "oversampling %lu is not supported\n", lval);
+ return ret;
+ }
+
+ mutex_lock(&indio_dev->mlock);
+ gpio_set_value(st->pdata->gpio_os0, (ret >> 0) & 1);
+ gpio_set_value(st->pdata->gpio_os1, (ret >> 1) & 1);
+ gpio_set_value(st->pdata->gpio_os1, (ret >> 2) & 1);
+ st->oversampling = lval;
+ mutex_unlock(&indio_dev->mlock);
+
+ return count;
+}
+
+static IIO_DEVICE_ATTR(oversampling_ratio, S_IRUGO | S_IWUSR,
+ ad7606_show_oversampling_ratio,
+ ad7606_store_oversampling_ratio, 0);
+static IIO_CONST_ATTR(oversampling_ratio_available, "0 2 4 8 16 32 64");
+
+static struct attribute *ad7606_attributes_os_and_range[] = {
+ &iio_dev_attr_in_voltage_range.dev_attr.attr,
+ &iio_const_attr_in_voltage_range_available.dev_attr.attr,
+ &iio_dev_attr_oversampling_ratio.dev_attr.attr,
+ &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ad7606_attribute_group_os_and_range = {
+ .attrs = ad7606_attributes_os_and_range,
+};
+
+static struct attribute *ad7606_attributes_os[] = {
+ &iio_dev_attr_oversampling_ratio.dev_attr.attr,
+ &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ad7606_attribute_group_os = {
+ .attrs = ad7606_attributes_os,
+};
+
+static struct attribute *ad7606_attributes_range[] = {
+ &iio_dev_attr_in_voltage_range.dev_attr.attr,
+ &iio_const_attr_in_voltage_range_available.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ad7606_attribute_group_range = {
+ .attrs = ad7606_attributes_range,
+};
+
+#define AD7606_CHANNEL(num) \
+ { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = num, \
+ .address = num, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
+ .scan_index = num, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_CPU, \
+ }, \
+ }
+
+static const struct iio_chan_spec ad7606_8_channels[] = {
+ AD7606_CHANNEL(0),
+ AD7606_CHANNEL(1),
+ AD7606_CHANNEL(2),
+ AD7606_CHANNEL(3),
+ AD7606_CHANNEL(4),
+ AD7606_CHANNEL(5),
+ AD7606_CHANNEL(6),
+ AD7606_CHANNEL(7),
+ IIO_CHAN_SOFT_TIMESTAMP(8),
+};
+
+static const struct iio_chan_spec ad7606_6_channels[] = {
+ AD7606_CHANNEL(0),
+ AD7606_CHANNEL(1),
+ AD7606_CHANNEL(2),
+ AD7606_CHANNEL(3),
+ AD7606_CHANNEL(4),
+ AD7606_CHANNEL(5),
+ IIO_CHAN_SOFT_TIMESTAMP(6),
+};
+
+static const struct iio_chan_spec ad7606_4_channels[] = {
+ AD7606_CHANNEL(0),
+ AD7606_CHANNEL(1),
+ AD7606_CHANNEL(2),
+ AD7606_CHANNEL(3),
+ IIO_CHAN_SOFT_TIMESTAMP(4),
+};
+
+static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
+ /*
+ * More devices added in future
+ */
+ [ID_AD7606_8] = {
+ .name = "ad7606",
+ .int_vref_mv = 2500,
+ .channels = ad7606_8_channels,
+ .num_channels = 8,
+ },
+ [ID_AD7606_6] = {
+ .name = "ad7606-6",
+ .int_vref_mv = 2500,
+ .channels = ad7606_6_channels,
+ .num_channels = 6,
+ },
+ [ID_AD7606_4] = {
+ .name = "ad7606-4",
+ .int_vref_mv = 2500,
+ .channels = ad7606_4_channels,
+ .num_channels = 4,
+ },
+};
+
+static int ad7606_request_gpios(struct ad7606_state *st)
+{
+ struct gpio gpio_array[3] = {
+ [0] = {
+ .gpio = st->pdata->gpio_os0,
+ .flags = GPIOF_DIR_OUT | ((st->oversampling & 1) ?
+ GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
+ .label = "AD7606_OS0",
+ },
+ [1] = {
+ .gpio = st->pdata->gpio_os1,
+ .flags = GPIOF_DIR_OUT | ((st->oversampling & 2) ?
+ GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
+ .label = "AD7606_OS1",
+ },
+ [2] = {
+ .gpio = st->pdata->gpio_os2,
+ .flags = GPIOF_DIR_OUT | ((st->oversampling & 4) ?
+ GPIOF_INIT_HIGH : GPIOF_INIT_LOW),
+ .label = "AD7606_OS2",
+ },
+ };
+ int ret;
+
+ if (gpio_is_valid(st->pdata->gpio_convst)) {
+ ret = gpio_request_one(st->pdata->gpio_convst,
+ GPIOF_OUT_INIT_LOW,
+ "AD7606_CONVST");
+ if (ret) {
+ dev_err(st->dev, "failed to request GPIO CONVST\n");
+ goto error_ret;
+ }
+ } else {
+ ret = -EIO;
+ goto error_ret;
+ }
+
+ if (gpio_is_valid(st->pdata->gpio_os0) &&
+ gpio_is_valid(st->pdata->gpio_os1) &&
+ gpio_is_valid(st->pdata->gpio_os2)) {
+ ret = gpio_request_array(gpio_array, ARRAY_SIZE(gpio_array));
+ if (ret < 0)
+ goto error_free_convst;
+ }
+
+ if (gpio_is_valid(st->pdata->gpio_reset)) {
+ ret = gpio_request_one(st->pdata->gpio_reset,
+ GPIOF_OUT_INIT_LOW,
+ "AD7606_RESET");
+ if (ret < 0)
+ goto error_free_os;
+ }
+
+ if (gpio_is_valid(st->pdata->gpio_range)) {
+ ret = gpio_request_one(st->pdata->gpio_range, GPIOF_DIR_OUT |
+ ((st->range == 10000) ? GPIOF_INIT_HIGH :
+ GPIOF_INIT_LOW), "AD7606_RANGE");
+ if (ret < 0)
+ goto error_free_reset;
+ }
+ if (gpio_is_valid(st->pdata->gpio_stby)) {
+ ret = gpio_request_one(st->pdata->gpio_stby,
+ GPIOF_OUT_INIT_HIGH,
+ "AD7606_STBY");
+ if (ret < 0)
+ goto error_free_range;
+ }
+
+ if (gpio_is_valid(st->pdata->gpio_frstdata)) {
+ ret = gpio_request_one(st->pdata->gpio_frstdata, GPIOF_IN,
+ "AD7606_FRSTDATA");
+ if (ret < 0)
+ goto error_free_stby;
+ }
+
+ return 0;
+
+error_free_stby:
+ if (gpio_is_valid(st->pdata->gpio_stby))
+ gpio_free(st->pdata->gpio_stby);
+error_free_range:
+ if (gpio_is_valid(st->pdata->gpio_range))
+ gpio_free(st->pdata->gpio_range);
+error_free_reset:
+ if (gpio_is_valid(st->pdata->gpio_reset))
+ gpio_free(st->pdata->gpio_reset);
+error_free_os:
+ if (gpio_is_valid(st->pdata->gpio_os0) &&
+ gpio_is_valid(st->pdata->gpio_os1) &&
+ gpio_is_valid(st->pdata->gpio_os2))
+ gpio_free_array(gpio_array, ARRAY_SIZE(gpio_array));
+error_free_convst:
+ gpio_free(st->pdata->gpio_convst);
+error_ret:
+ return ret;
+}
+
+static void ad7606_free_gpios(struct ad7606_state *st)
+{
+ if (gpio_is_valid(st->pdata->gpio_frstdata))
+ gpio_free(st->pdata->gpio_frstdata);
+ if (gpio_is_valid(st->pdata->gpio_stby))
+ gpio_free(st->pdata->gpio_stby);
+ if (gpio_is_valid(st->pdata->gpio_range))
+ gpio_free(st->pdata->gpio_range);
+ if (gpio_is_valid(st->pdata->gpio_reset))
+ gpio_free(st->pdata->gpio_reset);
+ if (gpio_is_valid(st->pdata->gpio_os0) &&
+ gpio_is_valid(st->pdata->gpio_os1) &&
+ gpio_is_valid(st->pdata->gpio_os2)) {
+ gpio_free(st->pdata->gpio_os2);
+ gpio_free(st->pdata->gpio_os1);
+ gpio_free(st->pdata->gpio_os0);
+ }
+ gpio_free(st->pdata->gpio_convst);
+}
+
+/**
+ * Interrupt handler
+ */
+static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
+{
+ struct iio_dev *indio_dev = dev_id;
+ struct ad7606_state *st = iio_priv(indio_dev);
+
+ if (iio_buffer_enabled(indio_dev)) {
+ schedule_work(&st->poll_work);
+ } else {
+ st->done = true;
+ wake_up_interruptible(&st->wq_data_avail);
+ }
+
+ return IRQ_HANDLED;
+};
+
+static const struct iio_info ad7606_info_no_os_or_range = {
+ .driver_module = THIS_MODULE,
+ .read_raw = &ad7606_read_raw,
+};
+
+static const struct iio_info ad7606_info_os_and_range = {
+ .driver_module = THIS_MODULE,
+ .read_raw = &ad7606_read_raw,
+ .attrs = &ad7606_attribute_group_os_and_range,
+};
+
+static const struct iio_info ad7606_info_os = {
+ .driver_module = THIS_MODULE,
+ .read_raw = &ad7606_read_raw,
+ .attrs = &ad7606_attribute_group_os,
+};
+
+static const struct iio_info ad7606_info_range = {
+ .driver_module = THIS_MODULE,
+ .read_raw = &ad7606_read_raw,
+ .attrs = &ad7606_attribute_group_range,
+};
+
+struct iio_dev *ad7606_probe(struct device *dev, int irq,
+ void __iomem *base_address,
+ unsigned id,
+ const struct ad7606_bus_ops *bops)
+{
+ struct ad7606_platform_data *pdata = dev->platform_data;
+ struct ad7606_state *st;
+ int ret;
+ struct iio_dev *indio_dev;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
+ if (!indio_dev)
+ return ERR_PTR(-ENOMEM);
+
+ st = iio_priv(indio_dev);
+
+ st->dev = dev;
+ st->bops = bops;
+ st->base_address = base_address;
+ st->range = pdata->default_range == 10000 ? 10000 : 5000;
+
+ ret = ad7606_oversampling_get_index(pdata->default_os);
+ if (ret < 0) {
+ dev_warn(dev, "oversampling %d is not supported\n",
+ pdata->default_os);
+ st->oversampling = 0;
+ } else {
+ st->oversampling = pdata->default_os;
+ }
+
+ st->reg = devm_regulator_get(dev, "vcc");
+ if (!IS_ERR(st->reg)) {
+ ret = regulator_enable(st->reg);
+ if (ret)
+ return ERR_PTR(ret);
+ }
+
+ st->pdata = pdata;
+ st->chip_info = &ad7606_chip_info_tbl[id];
+
+ indio_dev->dev.parent = dev;
+ if (gpio_is_valid(st->pdata->gpio_os0) &&
+ gpio_is_valid(st->pdata->gpio_os1) &&
+ gpio_is_valid(st->pdata->gpio_os2)) {
+ if (gpio_is_valid(st->pdata->gpio_range))
+ indio_dev->info = &ad7606_info_os_and_range;
+ else
+ indio_dev->info = &ad7606_info_os;
+ } else {
+ if (gpio_is_valid(st->pdata->gpio_range))
+ indio_dev->info = &ad7606_info_range;
+ else
+ indio_dev->info = &ad7606_info_no_os_or_range;
+ }
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->name = st->chip_info->name;
+ indio_dev->channels = st->chip_info->channels;
+ indio_dev->num_channels = st->chip_info->num_channels;
+
+ init_waitqueue_head(&st->wq_data_avail);
+
+ ret = ad7606_request_gpios(st);
+ if (ret)
+ goto error_disable_reg;
+
+ ret = ad7606_reset(st);
+ if (ret)
+ dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
+
+ ret = request_irq(irq, ad7606_interrupt,
+ IRQF_TRIGGER_FALLING, st->chip_info->name, indio_dev);
+ if (ret)
+ goto error_free_gpios;
+
+ ret = ad7606_register_ring_funcs_and_init(indio_dev);
+ if (ret)
+ goto error_free_irq;
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto error_unregister_ring;
+
+ return indio_dev;
+error_unregister_ring:
+ ad7606_ring_cleanup(indio_dev);
+
+error_free_irq:
+ free_irq(irq, indio_dev);
+
+error_free_gpios:
+ ad7606_free_gpios(st);
+
+error_disable_reg:
+ if (!IS_ERR(st->reg))
+ regulator_disable(st->reg);
+ return ERR_PTR(ret);
+}
+
+int ad7606_remove(struct iio_dev *indio_dev, int irq)
+{
+ struct ad7606_state *st = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ ad7606_ring_cleanup(indio_dev);
+
+ free_irq(irq, indio_dev);
+ if (!IS_ERR(st->reg))
+ regulator_disable(st->reg);
+
+ ad7606_free_gpios(st);
+
+ return 0;
+}
+
+void ad7606_suspend(struct iio_dev *indio_dev)
+{
+ struct ad7606_state *st = iio_priv(indio_dev);
+
+ if (gpio_is_valid(st->pdata->gpio_stby)) {
+ if (gpio_is_valid(st->pdata->gpio_range))
+ gpio_set_value(st->pdata->gpio_range, 1);
+ gpio_set_value(st->pdata->gpio_stby, 0);
+ }
+}
+
+void ad7606_resume(struct iio_dev *indio_dev)
+{
+ struct ad7606_state *st = iio_priv(indio_dev);
+
+ if (gpio_is_valid(st->pdata->gpio_stby)) {
+ if (gpio_is_valid(st->pdata->gpio_range))
+ gpio_set_value(st->pdata->gpio_range,
+ st->range == 10000);
+
+ gpio_set_value(st->pdata->gpio_stby, 1);
+ ad7606_reset(st);
+ }
+}
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
+MODULE_LICENSE("GPL v2");
Code Review / kvmfornfv.git / blobdiff