Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
---
drivers/iio/adc/Kconfig | 5 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/ad_sigma_delta.c | 557 ++++++++++++++++++++++++++++++++
include/linux/iio/adc/ad_sigma_delta.h | 173 ++++++++++
4 files changed, 736 insertions(+)
create mode 100644 drivers/iio/adc/ad_sigma_delta.c
create mode 100644 include/linux/iio/adc/ad_sigma_delta.h
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 8a78b4f..a2c5071 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -3,6 +3,11 @@
#
menu "Analog to digital converters"
+config AD_SIGMA_DELTA
+ tristate
+ select IIO_BUFFER
+ select IIO_TRIGGERED_BUFFER
+
config AD7266
tristate "Analog Devices AD7265/AD7266 ADC driver"
depends on SPI_MASTER
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 52eec25..5989356 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -2,5 +2,6 @@
# Makefile for IIO ADC drivers
#
+obj-$(CONFIG_AD_SIGMA_DELTA) += ad_sigma_delta.o
obj-$(CONFIG_AD7266) += ad7266.o
obj-$(CONFIG_AT91_ADC) += at91_adc.o
diff --git a/drivers/iio/adc/ad_sigma_delta.c b/drivers/iio/adc/ad_sigma_delta.c
new file mode 100644
index 0000000..555feb7
--- /dev/null
+++ b/drivers/iio/adc/ad_sigma_delta.c
@@ -0,0 +1,557 @@
+/*
+ * Support code for Analog Devices Sigma-Delta ADCs
+ *
+ * Copyright 2012 Analog Devices Inc.
+ * Author: Lars-Peter Clausen <lars@xxxxxxxxxx>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/err.h>
+#include <linux/module.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/adc/ad_sigma_delta.h>
+
+#include <asm/unaligned.h>
+
+
+#define AD_SD_COMM_CHAN_MASK 0x3
+
+#define AD_SD_REG_COMM 0x00
+#define AD_SD_REG_DATA 0x03
+
+/**
+ * ad_sd_set_comm() - Set communications register
+ *
+ * @sigma_delta: The sigma delta device
+ * @comm: New value for the communications register
+ */
+void ad_sd_set_comm(struct ad_sigma_delta *sigma_delta, uint8_t comm)
+{
+ /* Some variants use the lower two bits of the communications register
+ * to select the channel */
+ sigma_delta->comm = comm & AD_SD_COMM_CHAN_MASK;
+}
+EXPORT_SYMBOL_GPL(ad_sd_set_comm);
+
+/**
+ * ad_sd_write_reg() - Write a register
+ *
+ * @sigma_delta: The sigma delta device
+ * @reg: Address of the register
+ * @size: Size of the register (0-3)
+ * @val: Value to write to the register
+ *
+ * Returns 0 on success, an error code otherwise.
+ **/
+int ad_sd_write_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg,
+ unsigned int size, unsigned int val)
+{
+ uint8_t *data = sigma_delta->data;
+ struct spi_transfer t = {
+ .tx_buf = data,
+ .len = size + 1,
+ .cs_change = sigma_delta->bus_locked,
+ };
+ struct spi_message m;
+ int ret;
+
+ data[0] = (reg << sigma_delta->info->addr_shift) | sigma_delta->comm;
+
+ switch (size) {
+ case 3:
+ data[1] = val >> 16;
+ data[2] = val >> 8;
+ data[3] = val;
+ break;
+ case 2:
+ put_unaligned_be16(val, &data[1]);
+ break;
+ case 1:
+ data[1] = val;
+ break;
+ case 0:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ spi_message_init(&m);
+ spi_message_add_tail(&t, &m);
+
+ if (sigma_delta->bus_locked)
+ ret = spi_sync_locked(sigma_delta->spi, &m);
+ else
+ ret = spi_sync(sigma_delta->spi, &m);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ad_sd_write_reg);
+
+static int ad_sd_read_reg_raw(struct ad_sigma_delta *sigma_delta,
+ unsigned int reg, unsigned int size, uint8_t *val)
+{
+ uint8_t *data = sigma_delta->data;
+ int ret;
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = data,
+ .len = 1,
+ }, {
+ .rx_buf = val,
+ .len = size,
+ .cs_change = sigma_delta->bus_locked,
+ },
+ };
+ struct spi_message m;
+
+ spi_message_init(&m);
+
+ if (sigma_delta->info->has_registers) {
+ data[0] = reg << sigma_delta->info->addr_shift;
+ data[0] |= sigma_delta->info->read_mask;
+ spi_message_add_tail(&t[0], &m);
+ }
+ spi_message_add_tail(&t[1], &m);
+
+ if (sigma_delta->bus_locked)
+ ret = spi_sync_locked(sigma_delta->spi, &m);
+ else
+ ret = spi_sync(sigma_delta->spi, &m);
+
+ return ret;
+}
+
+/**
+ * ad_sd_read_reg() - Read a register
+ *
+ * @sigma_delta: The sigma delta device
+ * @reg: Address of the register
+ * @size: Size of the register (1-4)
+ * @val: Read value
+ *
+ * Returns 0 on success, an error code otherwise.
+ **/
+int ad_sd_read_reg(struct ad_sigma_delta *sigma_delta,
+ unsigned int reg, unsigned int size, unsigned int *val)
+{
+ int ret;
+
+ ret = ad_sd_read_reg_raw(sigma_delta, reg, size, sigma_delta->data);
+ if (ret < 0)
+ goto out;
+
+ switch (size) {
+ case 4:
+ *val = get_unaligned_be32(sigma_delta->data);
+ break;
+ case 3:
+ *val = (sigma_delta->data[0] << 16) |
+ (sigma_delta->data[1] << 8) |
+ sigma_delta->data[2];
+ break;
+ case 2:
+ *val = get_unaligned_be16(sigma_delta->data);
+ break;
+ case 1:
+ *val = sigma_delta->data[0];
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+out:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ad_sd_read_reg);
+
+static int ad_sd_calibrate(struct ad_sigma_delta *sigma_delta,
+ unsigned int mode, unsigned int channel)
+{
+ int ret;
+
+ ret = ad_sigma_delta_set_channel(sigma_delta, channel);
+ if (ret)
+ return ret;
+
+ spi_bus_lock(sigma_delta->spi->master);
+ sigma_delta->bus_locked = true;
+ INIT_COMPLETION(sigma_delta->completion);
+
+ ret = ad_sigma_delta_set_mode(sigma_delta, mode);
+ if (ret < 0)
+ goto out;
+
+ sigma_delta->irq_dis = false;
+ enable_irq(sigma_delta->spi->irq);
+ ret = wait_for_completion_timeout(&sigma_delta->completion, 2*HZ);
+ if (ret == 0) {
+ sigma_delta->irq_dis = true;
+ disable_irq_nosync(sigma_delta->spi->irq);
+ ret = -EIO;
+ } else {
+ ret = 0;
+ }
+out:
+ sigma_delta->bus_locked = false;
+ spi_bus_unlock(sigma_delta->spi->master);
+ ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_IDLE);
+
+ return ret;
+}
+
+/**
+ * ad_sd_calibrate_all() - Performs channel calibration
+ * @sigma_delta: The sigma delta device
+ * @cb: Array of channels and calibration type to perform
+ * @n: Number of items in cb
+ *
+ * Returns 0 on success, an error code otherwise.
+ **/
+int ad_sd_calibrate_all(struct ad_sigma_delta *sigma_delta,
+ const struct ad_sd_calib_data *cb, unsigned int n)
+{
+ unsigned int i;
+ int ret;
+
+ for (i = 0; i < n; i++) {
+ ret = ad_sd_calibrate(sigma_delta, cb[i].mode, cb[i].channel);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ad_sd_calibrate_all);
+
+/**
+ * ad_sigma_delta_single_conversion() - Performs a single data conversion
+ * @indio_dev: The IIO device
+ * @chan: The conversion is done for this channel
+ * @val: Pointer to the location where to store the read value
+ *
+ * Returns: 0 on success, an error value otherwise.
+ */
+int ad_sigma_delta_single_conversion(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, int *val)
+{
+ struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
+ unsigned int sample, raw_sample;
+ int ret = 0;
+
+ if (iio_buffer_enabled(indio_dev))
+ return -EBUSY;
+
+ mutex_lock(&indio_dev->mlock);
+ ad_sigma_delta_set_channel(sigma_delta, chan->address);
+
+ spi_bus_lock(sigma_delta->spi->master);
+ sigma_delta->bus_locked = true;
+ INIT_COMPLETION(sigma_delta->completion);
+
+ ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_SINGLE);
+
+ sigma_delta->irq_dis = false;
+ enable_irq(sigma_delta->spi->irq);
+ ret = wait_for_completion_interruptible_timeout(
+ &sigma_delta->completion, HZ);
+
+ sigma_delta->bus_locked = false;
+ spi_bus_unlock(sigma_delta->spi->master);
+
+ if (ret == 0)
+ ret = -EIO;
+ if (ret < 0)
+ goto out;
+
+ ret = ad_sd_read_reg(sigma_delta, AD_SD_REG_DATA,
+ DIV_ROUND_UP(chan->scan_type.realbits + chan->scan_type.shift, 8),
+ &raw_sample);
+
+out:
+ if (!sigma_delta->irq_dis) {
+ disable_irq_nosync(sigma_delta->spi->irq);
+ sigma_delta->irq_dis = true;
+ }
+
+ ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_IDLE);
+ mutex_unlock(&indio_dev->mlock);
+
+ if (ret)
+ return ret;
+
+ sample = raw_sample >> chan->scan_type.shift;
+ sample &= (1 << chan->scan_type.realbits) - 1;
+ *val = sample;
+
+ ret = ad_sigma_delta_postprocess_sample(sigma_delta, raw_sample);
+ if (ret)
+ return ret;
+
+ return IIO_VAL_INT;
+}
+EXPORT_SYMBOL_GPL(ad_sigma_delta_single_conversion);
+
+static int ad_sd_buffer_postenable(struct iio_dev *indio_dev)
+{
+ struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
+ unsigned int channel;
+ int ret;
+
+ ret = iio_triggered_buffer_postenable(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ channel = find_first_bit(indio_dev->active_scan_mask,
+ indio_dev->masklength);
+ ret = ad_sigma_delta_set_channel(sigma_delta,
+ indio_dev->channels[channel].address);
+ if (ret)
+ goto err_predisable;
+
+ spi_bus_lock(sigma_delta->spi->master);
+ sigma_delta->bus_locked = true;
+ ret = ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_CONTINUOUS);
+ if (ret)
+ goto err_unlock;
+
+ sigma_delta->irq_dis = false;
+ enable_irq(sigma_delta->spi->irq);
+
+ return 0;
+
+err_unlock:
+ spi_bus_unlock(sigma_delta->spi->master);
+err_predisable:
+
+ return ret;
+}
+
+static int ad_sd_buffer_postdisable(struct iio_dev *indio_dev)
+{
+ struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
+
+ INIT_COMPLETION(sigma_delta->completion);
+ wait_for_completion_timeout(&sigma_delta->completion, HZ);
+
+ if (!sigma_delta->irq_dis) {
+ disable_irq_nosync(sigma_delta->spi->irq);
+ sigma_delta->irq_dis = true;
+ }
+
+ ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_IDLE);
+
+ sigma_delta->bus_locked = false;
+ return spi_bus_unlock(sigma_delta->spi->master);
+}
+
+static irqreturn_t ad_sd_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
+ unsigned int reg_size;
+ uint8_t data[16];
+ int ret;
+
+ memset(data, 0x00, 16);
+
+ /* Guaranteed to be aligned with 8 byte boundary */
+ if (indio_dev->scan_timestamp)
+ ((s64 *)data)[1] = pf->timestamp;
+
+ reg_size = indio_dev->channels[0].scan_type.realbits +
+ indio_dev->channels[0].scan_type.shift;
+ reg_size = DIV_ROUND_UP(reg_size, 8);
+
+ switch (reg_size) {
+ case 4:
+ case 2:
+ case 1:
+ ret = ad_sd_read_reg_raw(sigma_delta, AD_SD_REG_DATA,
+ reg_size, &data[0]);
+ break;
+ case 3:
+ /* We store 24 bit samples in a 32 bit word. Keep the upper
+ * byte set to zero. */
+ ret = ad_sd_read_reg_raw(sigma_delta, AD_SD_REG_DATA,
+ reg_size, &data[1]);
+ break;
+ }
+
+ iio_push_to_buffer(indio_dev->buffer, (uint8_t *)data, pf->timestamp);
+
+ iio_trigger_notify_done(indio_dev->trig);
+ sigma_delta->irq_dis = false;
+ enable_irq(sigma_delta->spi->irq);
+
+ return IRQ_HANDLED;
+}
+
+static const struct iio_buffer_setup_ops ad_sd_buffer_setup_ops = {
+ .preenable = &iio_sw_buffer_preenable,
+ .postenable = &ad_sd_buffer_postenable,
+ .predisable = &iio_triggered_buffer_predisable,
+ .postdisable = &ad_sd_buffer_postdisable,
+ .validate_scan_mask = &iio_validate_scan_mask_onehot,
+};
+
+static irqreturn_t ad_sd_data_rdy_trig_poll(int irq, void *private)
+{
+ struct ad_sigma_delta *sigma_delta = private;
+
+ complete(&sigma_delta->completion);
+ disable_irq_nosync(irq);
+ sigma_delta->irq_dis = true;
+ iio_trigger_poll(sigma_delta->trig, iio_get_time_ns());
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * ad_sd_validate_trigger() - validate_trigger callback for ad_sigma_delta devices
+ * @indio_dev: The IIO device
+ * @trig: The new trigger
+ *
+ * Returns: 0 if the 'trig' matches the trigger registered by the ad_sigma_delta
+ * device, -EINVAL otherwise.
+ */
+int ad_sd_validate_trigger(struct iio_dev *indio_dev, struct iio_trigger *trig)
+{
+ struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
+
+ if (sigma_delta->trig != trig)
+ return -EINVAL;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ad_sd_validate_trigger);
+
+static const struct iio_trigger_ops ad_sd_trigger_ops = {
+ .owner = THIS_MODULE,
+};
+
+static int ad_sd_probe_trigger(struct iio_dev *indio_dev)
+{
+ struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
+ int ret;
+
+ sigma_delta->trig = iio_trigger_alloc("%s-dev%d", indio_dev->name,
+ indio_dev->id);
+ if (sigma_delta->trig == NULL) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ sigma_delta->trig->ops = &ad_sd_trigger_ops;
+ init_completion(&sigma_delta->completion);
+
+ ret = request_irq(sigma_delta->spi->irq,
+ ad_sd_data_rdy_trig_poll,
+ IRQF_TRIGGER_LOW,
+ indio_dev->name,
+ sigma_delta);
+ if (ret)
+ goto error_free_trig;
+
+ if (!sigma_delta->irq_dis) {
+ sigma_delta->irq_dis = true;
+ disable_irq_nosync(sigma_delta->spi->irq);
+ }
+ sigma_delta->trig->dev.parent = &sigma_delta->spi->dev;
+ sigma_delta->trig->private_data = sigma_delta;
+
+ ret = iio_trigger_register(sigma_delta->trig);
+ if (ret)
+ goto error_free_irq;
+
+ /* select default trigger */
+ indio_dev->trig = sigma_delta->trig;
+
+ return 0;
+
+error_free_irq:
+ free_irq(sigma_delta->spi->irq, sigma_delta);
+error_free_trig:
+ iio_trigger_free(sigma_delta->trig);
+error_ret:
+ return ret;
+}
+
+static void ad_sd_remove_trigger(struct iio_dev *indio_dev)
+{
+ struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
+
+ iio_trigger_unregister(sigma_delta->trig);
+ free_irq(sigma_delta->spi->irq, sigma_delta);
+ iio_trigger_free(sigma_delta->trig);
+}
+
+/**
+ * ad_sd_setup_buffer_and_trigger() -
+ * @indio_dev: The IIO device
+ */
+int ad_sd_setup_buffer_and_trigger(struct iio_dev *indio_dev)
+{
+ int ret;
+
+ ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
+ &ad_sd_trigger_handler, &ad_sd_buffer_setup_ops);
+ if (ret)
+ return ret;
+
+ ret = ad_sd_probe_trigger(indio_dev);
+ if (ret) {
+ iio_triggered_buffer_cleanup(indio_dev);
+ return ret;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ad_sd_setup_buffer_and_trigger);
+
+/**
+ * ad_sd_cleanup_buffer_and_trigger() -
+ * @indio_dev: The IIO device
+ */
+void ad_sd_cleanup_buffer_and_trigger(struct iio_dev *indio_dev)
+{
+ ad_sd_remove_trigger(indio_dev);
+ iio_triggered_buffer_cleanup(indio_dev);
+}
+EXPORT_SYMBOL_GPL(ad_sd_cleanup_buffer_and_trigger);
+
+/**
+ * ad_sd_init() - Initializes a ad_sigma_delta struct
+ * @sigma_delta: The ad_sigma_delta device
+ * @indio_dev: The IIO device which the Sigma Delta device is used for
+ * @spi: The SPI device for the ad_sigma_delta device
+ * @info: Device specific callbacks and options
+ *
+ * This function needs to be called before any other operations are performed on
+ * the ad_sigma_delta struct.
+ */
+int ad_sd_init(struct ad_sigma_delta *sigma_delta, struct iio_dev *indio_dev,
+ struct spi_device *spi, const struct ad_sigma_delta_info *info)
+{
+ sigma_delta->spi = spi;
+ sigma_delta->info = info;
+ iio_device_set_drvdata(indio_dev, sigma_delta);
+
+ return 0;
+}
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Analog Devices Sigma-Delta ADCs");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/iio/adc/ad_sigma_delta.h b/include/linux/iio/adc/ad_sigma_delta.h
new file mode 100644
index 0000000..2e4eab9
--- /dev/null
+++ b/include/linux/iio/adc/ad_sigma_delta.h
@@ -0,0 +1,173 @@
+/*
+ * Support code for Analog Devices Sigma-Delta ADCs
+ *
+ * Copyright 2012 Analog Devices Inc.
+ * Author: Lars-Peter Clausen <lars@xxxxxxxxxx>
+ *
+ * Licensed under the GPL-2.
+ */
+#ifndef __AD_SIGMA_DELTA_H__
+#define __AD_SIGMA_DELTA_H__
+
+enum ad_sigma_delta_mode {
+ AD_SD_MODE_CONTINUOUS = 0,
+ AD_SD_MODE_SINGLE = 1,
+ AD_SD_MODE_IDLE = 2,
+ AD_SD_MODE_POWERDOWN = 3,
+};
+
+/**
+ * struct ad_sigma_delta_calib_data - Calibration data for Sigma Delta devices
+ * @mode: Calibration mode.
+ * @channel: Calibration channel.
+ */
+struct ad_sd_calib_data {
+ unsigned int mode;
+ unsigned int channel;
+};
+
+struct ad_sigma_delta;
+struct iio_dev;
+
+/**
+ * struct ad_sigma_delta_info - Sigma Delta driver specific callbacks and options
+ * @set_channel: Will be called to select the current channel, may be NULL.
+ * @set_mode: Will be called to select the current mode, may be NULL.
+ * @postprocess_sample: Is called for each sampled data word, can be used to
+ * modify or drop the sample data, it, may be NULL.
+ * @has_registers: true if the device has writable and readable registers, false
+ * if there is just one read-only sample data shift register.
+ * @addr_shift: Shift of the register address in the communications register.
+ * @read_mask: Mask for the communications register having the read bit set.
+ */
+struct ad_sigma_delta_info {
+ int (*set_channel)(struct ad_sigma_delta *, unsigned int channel);
+ int (*set_mode)(struct ad_sigma_delta *, enum ad_sigma_delta_mode mode);
+ int (*postprocess_sample)(struct ad_sigma_delta *, unsigned int raw_sample);
+ bool has_registers;
+ unsigned int addr_shift;
+ unsigned int read_mask;
+};
+
+/**
+ * struct ad_sigma_delta - Sigma Delta device struct
+ * @spi: The spi device associated with the Sigma Delta device.
+ * @trig: The IIO trigger associated with the Sigma Delta device.
+ *
+ * Most of the fields are private to the sigma delta library code and should not
+ * be accessed by individual drivers.
+ */
+struct ad_sigma_delta {
+ struct spi_device *spi;
+ struct iio_trigger *trig;
+
+/* private: */
+ struct completion completion;
+ bool irq_dis;
+
+ bool bus_locked;
+
+ uint8_t comm;
+
+ const struct ad_sigma_delta_info *info;
+
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ uint8_t data[4] ____cacheline_aligned;
+};
+
+static inline int ad_sigma_delta_set_channel(struct ad_sigma_delta *sd,
+ unsigned int channel)
+{
+ if (sd->info->set_channel)
+ return sd->info->set_channel(sd, channel);
+
+ return 0;
+}
+
+static inline int ad_sigma_delta_set_mode(struct ad_sigma_delta *sd,
+ unsigned int mode)
+{
+ if (sd->info->set_mode)
+ return sd->info->set_mode(sd, mode);
+
+ return 0;
+}
+
+static inline int ad_sigma_delta_postprocess_sample(struct ad_sigma_delta *sd,
+ unsigned int raw_sample)
+{
+ if (sd->info->postprocess_sample)
+ return sd->info->postprocess_sample(sd, raw_sample);
+
+ return 0;
+}
+
+void ad_sd_set_comm(struct ad_sigma_delta *sigma_delta, uint8_t comm);
+int ad_sd_write_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg,
+ unsigned int size, unsigned int val);
+int ad_sd_read_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg,
+ unsigned int size, unsigned int *val);
+
+int ad_sigma_delta_single_conversion(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, int *val);
+int ad_sd_calibrate_all(struct ad_sigma_delta *sigma_delta,
+ const struct ad_sd_calib_data *cd, unsigned int n);
+int ad_sd_init(struct ad_sigma_delta *sigma_delta, struct iio_dev *indio_dev,
+ struct spi_device *spi, const struct ad_sigma_delta_info *info);
+
+int ad_sd_setup_buffer_and_trigger(struct iio_dev *indio_dev);
+void ad_sd_cleanup_buffer_and_trigger(struct iio_dev *indio_dev);
+
+int ad_sd_validate_trigger(struct iio_dev *indio_dev, struct iio_trigger *trig);
+
+#define __AD_SD_CHANNEL(_si, _channel1, _channel2, _address, _bits, \
+ _storagebits, _shift, _extend_name, _type) \
+ { \
+ .type = (_type), \
+ .differential = (_channel2 == -1 ? 0 : 1), \
+ .indexed = 1, \
+ .channel = (_channel1), \
+ .channel2 = (_channel2), \
+ .address = (_address), \
+ .extend_name = (_extend_name), \
+ .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
+ IIO_CHAN_INFO_SCALE_SHARED_BIT | \
+ IIO_CHAN_INFO_OFFSET_SEPARATE_BIT, \
+ .scan_index = (_si), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = (_bits), \
+ .storagebits = (_storagebits), \
+ .shift = (_shift), \
+ .endianness = IIO_BE, \
+ }, \
+ }
+
+#define AD_SD_DIFF_CHANNEL(_si, _channel1, _channel2, _address, _bits, \
+ _storagebits, _shift) \
+ __AD_SD_CHANNEL(_si, _channel1, _channel2, _address, _bits, \
+ _storagebits, _shift, NULL, IIO_VOLTAGE)
+
+#define AD_SD_SHORTED_CHANNEL(_si, _channel, _address, _bits, \
+ _storagebits, _shift) \
+ __AD_SD_CHANNEL(_si, _channel, _channel, _address, _bits, \
+ _storagebits, _shift, "shorted", IIO_VOLTAGE)
+
+#define AD_SD_CHANNEL(_si, _channel, _address, _bits, \
+ _storagebits, _shift) \
+ __AD_SD_CHANNEL(_si, _channel, -1, _address, _bits, \
+ _storagebits, _shift, NULL, IIO_VOLTAGE)
+
+#define AD_SD_TEMP_CHANNEL(_si, _address, _bits, _storagebits, _shift) \
+ __AD_SD_CHANNEL(_si, 0, -1, _address, _bits, \
+ _storagebits, _shift, NULL, IIO_TEMP)
+
+#define AD_SD_SUPPLY_CHANNEL(_si, _channel, _address, _bits, _storagebits, \
+ _shift) \
+ __AD_SD_CHANNEL(_si, _channel, -1, _address, _bits, \
+ _storagebits, _shift, "supply", IIO_VOLTAGE)
+
+#endif
