The existing ad7745 driver didn't conform with the IIO spec for such devices.
It was way simpler to rewrite the existing driver, than actually fixing it.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
To compile this driver as a module, choose M here: the
module will be called AD7793.
-config AD7745
+config AD7746
tristate "Analog Devices AD7745, AD7746 AD7747 capacitive sensor driver"
depends on I2C
help
obj-$(CONFIG_AD7152) += ad7152.o
obj-$(CONFIG_AD7291) += ad7291.o
obj-$(CONFIG_AD7314) += ad7314.o
-obj-$(CONFIG_AD7745) += ad7745.o
+obj-$(CONFIG_AD7746) += ad7746.o
obj-$(CONFIG_AD7780) += ad7780.o
obj-$(CONFIG_AD7793) += ad7793.o
obj-$(CONFIG_AD7816) += ad7816.o
+++ /dev/null
-/*
- * AD774X capacitive sensor driver supporting AD7745/6/7
- *
- * Copyright 2010 Analog Devices Inc.
- *
- * Licensed under the GPL-2 or later.
- */
-
-#include <linux/interrupt.h>
-#include <linux/gpio.h>
-#include <linux/device.h>
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/sysfs.h>
-#include <linux/list.h>
-#include <linux/i2c.h>
-#include <linux/module.h>
-
-#include "../iio.h"
-#include "../sysfs.h"
-
-/*
- * AD774X registers definition
- */
-
-#define AD774X_STATUS 0
-#define AD774X_STATUS_RDY (1 << 2)
-#define AD774X_STATUS_RDYVT (1 << 1)
-#define AD774X_STATUS_RDYCAP (1 << 0)
-#define AD774X_CAP_DATA_HIGH 1
-#define AD774X_CAP_DATA_MID 2
-#define AD774X_CAP_DATA_LOW 3
-#define AD774X_VT_DATA_HIGH 4
-#define AD774X_VT_DATA_MID 5
-#define AD774X_VT_DATA_LOW 6
-#define AD774X_CAP_SETUP 7
-#define AD774X_VT_SETUP 8
-#define AD774X_EXEC_SETUP 9
-#define AD774X_CFG 10
-#define AD774X_CAPDACA 11
-#define AD774X_CAPDACB 12
-#define AD774X_CAPDAC_EN (1 << 7)
-#define AD774X_CAP_OFFH 13
-#define AD774X_CAP_OFFL 14
-#define AD774X_CAP_GAINH 15
-#define AD774X_CAP_GAINL 16
-#define AD774X_VOLT_GAINH 17
-#define AD774X_VOLT_GAINL 18
-
-#define AD774X_MAX_CONV_MODE 6
-
-/*
- * struct ad774x_chip_info - chip specifc information
- */
-
-struct ad774x_chip_info {
- struct i2c_client *client;
- bool inter;
- u16 cap_offs; /* Capacitive offset */
- u16 cap_gain; /* Capacitive gain calibration */
- u16 volt_gain; /* Voltage gain calibration */
- u8 cap_setup;
- u8 vt_setup;
- u8 exec_setup;
-
- char *conversion_mode;
-};
-
-struct ad774x_conversion_mode {
- char *name;
- u8 reg_cfg;
-};
-
-static struct ad774x_conversion_mode
-ad774x_conv_mode_table[AD774X_MAX_CONV_MODE] = {
- { "idle", 0 },
- { "continuous-conversion", 1 },
- { "single-conversion", 2 },
- { "power-down", 3 },
- { "offset-calibration", 5 },
- { "gain-calibration", 6 },
-};
-
-/*
- * ad774x register access by I2C
- */
-
-static int ad774x_i2c_read(struct ad774x_chip_info *chip, u8 reg, u8 *data, int len)
-{
- struct i2c_client *client = chip->client;
- int ret;
-
- ret = i2c_master_send(client, ®, 1);
- if (ret < 0) {
- dev_err(&client->dev, "I2C write error\n");
- return ret;
- }
-
- ret = i2c_master_recv(client, data, len);
- if (ret < 0) {
- dev_err(&client->dev, "I2C read error\n");
- return ret;
- }
-
- return ret;
-}
-
-static int ad774x_i2c_write(struct ad774x_chip_info *chip, u8 reg, u8 data)
-{
- struct i2c_client *client = chip->client;
- int ret;
-
- u8 tx[2] = {
- reg,
- data,
- };
-
- ret = i2c_master_send(client, tx, 2);
- if (ret < 0)
- dev_err(&client->dev, "I2C write error\n");
-
- return ret;
-}
-
-/*
- * sysfs nodes
- */
-
-#define IIO_DEV_ATTR_AVAIL_CONVERSION_MODES(_show) \
- IIO_DEVICE_ATTR(available_conversion_modes, S_IRUGO, _show, NULL, 0)
-#define IIO_DEV_ATTR_CONVERSION_MODE(_mode, _show, _store) \
- IIO_DEVICE_ATTR(conversion_mode, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_SETUP(_mode, _show, _store) \
- IIO_DEVICE_ATTR(in_capacitance_setup, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_VT_SETUP(_mode, _show, _store) \
- IIO_DEVICE_ATTR(in_voltage0_setup, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_EXEC_SETUP(_mode, _show, _store) \
- IIO_DEVICE_ATTR(exec_setup, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_VOLT_GAIN(_mode, _show, _store) \
- IIO_DEVICE_ATTR(in_voltage0_gain, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_OFFS(_mode, _show, _store) \
- IIO_DEVICE_ATTR(in_capacitance_offs, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_GAIN(_mode, _show, _store) \
- IIO_DEVICE_ATTR(in_capacitance_gain, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_DATA(_show) \
- IIO_DEVICE_ATTR(in_capacitance0_raw, S_IRUGO, _show, NULL, 0)
-#define IIO_DEV_ATTR_VT_DATA(_show) \
- IIO_DEVICE_ATTR(in_voltage0_raw, S_IRUGO, _show, NULL, 0)
-
-static ssize_t ad774x_show_conversion_modes(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- int i;
- int len = 0;
-
- for (i = 0; i < AD774X_MAX_CONV_MODE; i++)
- len += sprintf(buf + len, "%s ", ad774x_conv_mode_table[i].name);
-
- len += sprintf(buf + len, "\n");
-
- return len;
-}
-
-static IIO_DEV_ATTR_AVAIL_CONVERSION_MODES(ad774x_show_conversion_modes);
-
-static ssize_t ad774x_show_conversion_mode(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
-
- return sprintf(buf, "%s\n", chip->conversion_mode);
-}
-
-static ssize_t ad774x_store_conversion_mode(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
- u8 cfg;
- int i;
-
- ad774x_i2c_read(chip, AD774X_CFG, &cfg, 1);
-
- for (i = 0; i < AD774X_MAX_CONV_MODE; i++) {
- if (strncmp(buf, ad774x_conv_mode_table[i].name,
- strlen(ad774x_conv_mode_table[i].name) - 1) == 0) {
- chip->conversion_mode = ad774x_conv_mode_table[i].name;
- cfg |= 0x18 | ad774x_conv_mode_table[i].reg_cfg;
- ad774x_i2c_write(chip, AD774X_CFG, cfg);
- return len;
- }
- }
-
- dev_err(dev, "not supported conversion mode\n");
-
- return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CONVERSION_MODE(S_IRUGO | S_IWUSR,
- ad774x_show_conversion_mode,
- ad774x_store_conversion_mode);
-
-static ssize_t ad774x_show_dac_value(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
- struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
- u8 data;
-
- ad774x_i2c_read(chip, this_attr->address, &data, 1);
-
- return sprintf(buf, "%02x\n", data & 0x7F);
-}
-
-static ssize_t ad774x_store_dac_value(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
- struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
- unsigned long data;
- int ret;
-
- ret = strict_strtoul(buf, 10, &data);
-
- if (!ret) {
- ad774x_i2c_write(chip, this_attr->address,
- (data ? AD774X_CAPDAC_EN : 0) | (data & 0x7F));
- return len;
- }
-
- return -EINVAL;
-}
-
-static IIO_DEVICE_ATTR(out_capacitance0_raw, S_IRUGO | S_IWUSR,
- ad774x_show_dac_value,
- ad774x_store_dac_value,
- AD774X_CAPDACA);
-
-static IIO_DEVICE_ATTR(out_capacitance1_raw, S_IRUGO | S_IWUSR,
- ad774x_show_dac_value,
- ad774x_store_dac_value,
- AD774X_CAPDACB);
-
-static ssize_t ad774x_show_cap_setup(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
-
- return sprintf(buf, "0x%02x\n", chip->cap_setup);
-}
-
-static ssize_t ad774x_store_cap_setup(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
- unsigned long data;
- int ret;
-
- ret = strict_strtoul(buf, 10, &data);
-
- if ((!ret) && (data < 0x100)) {
- ad774x_i2c_write(chip, AD774X_CAP_SETUP, data);
- chip->cap_setup = data;
- return len;
- }
-
- return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CAP_SETUP(S_IRUGO | S_IWUSR,
- ad774x_show_cap_setup,
- ad774x_store_cap_setup);
-
-static ssize_t ad774x_show_vt_setup(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
-
- return sprintf(buf, "0x%02x\n", chip->vt_setup);
-}
-
-static ssize_t ad774x_store_vt_setup(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
- unsigned long data;
- int ret;
-
- ret = strict_strtoul(buf, 10, &data);
-
- if ((!ret) && (data < 0x100)) {
- ad774x_i2c_write(chip, AD774X_VT_SETUP, data);
- chip->vt_setup = data;
- return len;
- }
-
- return -EINVAL;
-}
-
-static IIO_DEV_ATTR_VT_SETUP(S_IRUGO | S_IWUSR,
- ad774x_show_vt_setup,
- ad774x_store_vt_setup);
-
-static ssize_t ad774x_show_exec_setup(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
-
- return sprintf(buf, "0x%02x\n", chip->exec_setup);
-}
-
-static ssize_t ad774x_store_exec_setup(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
- unsigned long data;
- int ret;
-
- ret = strict_strtoul(buf, 10, &data);
-
- if ((!ret) && (data < 0x100)) {
- ad774x_i2c_write(chip, AD774X_EXEC_SETUP, data);
- chip->exec_setup = data;
- return len;
- }
-
- return -EINVAL;
-}
-
-static IIO_DEV_ATTR_EXEC_SETUP(S_IRUGO | S_IWUSR,
- ad774x_show_exec_setup,
- ad774x_store_exec_setup);
-
-static ssize_t ad774x_show_volt_gain(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
-
- return sprintf(buf, "%d\n", chip->volt_gain);
-}
-
-static ssize_t ad774x_store_volt_gain(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
- unsigned long data;
- int ret;
-
- ret = strict_strtoul(buf, 10, &data);
-
- if ((!ret) && (data < 0x10000)) {
- ad774x_i2c_write(chip, AD774X_VOLT_GAINH, data >> 8);
- ad774x_i2c_write(chip, AD774X_VOLT_GAINL, data);
- chip->volt_gain = data;
- return len;
- }
-
- return -EINVAL;
-}
-
-static IIO_DEV_ATTR_VOLT_GAIN(S_IRUGO | S_IWUSR,
- ad774x_show_volt_gain,
- ad774x_store_volt_gain);
-
-static ssize_t ad774x_show_cap_data(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
- unsigned long data;
- char tmp[3];
-
- ad774x_i2c_read(chip, AD774X_CAP_DATA_HIGH, tmp, 3);
- data = ((int)tmp[0] << 16) | ((int)tmp[1] << 8) | (int)tmp[2];
-
- return sprintf(buf, "%ld\n", data);
-}
-
-static IIO_DEV_ATTR_CAP_DATA(ad774x_show_cap_data);
-
-static ssize_t ad774x_show_vt_data(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
- unsigned long data;
- char tmp[3];
-
- ad774x_i2c_read(chip, AD774X_VT_DATA_HIGH, tmp, 3);
- data = ((int)tmp[0] << 16) | ((int)tmp[1] << 8) | (int)tmp[2];
-
- return sprintf(buf, "%ld\n", data);
-}
-
-static IIO_DEV_ATTR_VT_DATA(ad774x_show_vt_data);
-
-static ssize_t ad774x_show_cap_offs(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
-
- return sprintf(buf, "%d\n", chip->cap_offs);
-}
-
-static ssize_t ad774x_store_cap_offs(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
- unsigned long data;
- int ret;
-
- ret = strict_strtoul(buf, 10, &data);
-
- if ((!ret) && (data < 0x10000)) {
- ad774x_i2c_write(chip, AD774X_CAP_OFFH, data >> 8);
- ad774x_i2c_write(chip, AD774X_CAP_OFFL, data);
- chip->cap_offs = data;
- return len;
- }
-
- return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CAP_OFFS(S_IRUGO | S_IWUSR,
- ad774x_show_cap_offs,
- ad774x_store_cap_offs);
-
-static ssize_t ad774x_show_cap_gain(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
-
- return sprintf(buf, "%d\n", chip->cap_gain);
-}
-
-static ssize_t ad774x_store_cap_gain(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
-{
- struct iio_dev *dev_info = dev_get_drvdata(dev);
- struct ad774x_chip_info *chip = iio_priv(dev_info);
- unsigned long data;
- int ret;
-
- ret = strict_strtoul(buf, 10, &data);
-
- if ((!ret) && (data < 0x10000)) {
- ad774x_i2c_write(chip, AD774X_CAP_GAINH, data >> 8);
- ad774x_i2c_write(chip, AD774X_CAP_GAINL, data);
- chip->cap_gain = data;
- return len;
- }
-
- return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CAP_GAIN(S_IRUGO | S_IWUSR,
- ad774x_show_cap_gain,
- ad774x_store_cap_gain);
-
-static struct attribute *ad774x_attributes[] = {
- &iio_dev_attr_available_conversion_modes.dev_attr.attr,
- &iio_dev_attr_conversion_mode.dev_attr.attr,
- &iio_dev_attr_in_capacitance_setup.dev_attr.attr,
- &iio_dev_attr_in_voltage0_setup.dev_attr.attr,
- &iio_dev_attr_exec_setup.dev_attr.attr,
- &iio_dev_attr_in_capacitance_offs.dev_attr.attr,
- &iio_dev_attr_in_capacitance_gain.dev_attr.attr,
- &iio_dev_attr_in_voltage0_gain.dev_attr.attr,
- &iio_dev_attr_in_voltage0_raw.dev_attr.attr,
- &iio_dev_attr_in_capacitance0_raw.dev_attr.attr,
- &iio_dev_attr_out_capacitance0_raw.dev_attr.attr,
- &iio_dev_attr_out_capacitance1_raw.dev_attr.attr,
- NULL,
-};
-
-static const struct attribute_group ad774x_attribute_group = {
- .attrs = ad774x_attributes,
-};
-
-/*
- * data ready events
- */
-
-#define IIO_EVENT_CODE_CAP_RDY 0
-#define IIO_EVENT_CODE_VT_RDY 1
-
-#define IIO_EVENT_ATTR_CAP_RDY_SH(_evlist, _show, _store, _mask) \
- IIO_EVENT_ATTR_SH(cap_rdy, _evlist, _show, _store, _mask)
-
-#define IIO_EVENT_ATTR_VT_RDY_SH(_evlist, _show, _store, _mask) \
- IIO_EVENT_ATTR_SH(vt_rdy, _evlist, _show, _store, _mask)
-
-static irqreturn_t ad774x_event_handler(int irq, void *private)
-{
- struct iio_dev *indio_dev = private;
- struct ad774x_chip_info *chip = iio_priv(indio_dev);
- u8 int_status;
-
- ad774x_i2c_read(chip, AD774X_STATUS, &int_status, 1);
-
- if (int_status & AD774X_STATUS_RDYCAP)
- iio_push_event(indio_dev,
- IIO_EVENT_CODE_CAP_RDY,
- iio_get_time_ns());
-
- if (int_status & AD774X_STATUS_RDYVT)
- iio_push_event(indio_dev,
- IIO_EVENT_CODE_VT_RDY,
- iio_get_time_ns());
-
- return IRQ_HANDLED;
-}
-
-static IIO_CONST_ATTR(cap_rdy_en, "1");
-static IIO_CONST_ATTR(vt_rdy_en, "1");
-
-static struct attribute *ad774x_event_attributes[] = {
- &iio_const_attr_cap_rdy_en.dev_attr.attr,
- &iio_const_attr_vt_rdy_en.dev_attr.attr,
- NULL,
-};
-
-static struct attribute_group ad774x_event_attribute_group = {
- .attrs = ad774x_event_attributes,
- .name = "events",
-};
-
-static const struct iio_info ad774x_info = {
- .attrs = &ad774x_event_attribute_group,
- .event_attrs = &ad774x_event_attribute_group,
- .driver_module = THIS_MODULE,
-};
-/*
- * device probe and remove
- */
-
-static int __devinit ad774x_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
-{
- int ret;
- struct ad774x_chip_info *chip;
- struct iio_dev *indio_dev;
-
- indio_dev = iio_allocate_device(sizeof(*chip));
- if (indio_dev == NULL) {
- ret = -ENOMEM;
- goto error_ret;
- }
- chip = iio_priv(indio_dev);
- /* this is only used for device removal purposes */
- i2c_set_clientdata(client, indio_dev);
-
- chip->client = client;
-
- /* Establish that the iio_dev is a child of the i2c device */
- indio_dev->name = id->name;
- indio_dev->dev.parent = &client->dev;
- indio_dev->info = &ad774x_info;
- indio_dev->modes = INDIO_DIRECT_MODE;
-
- if (client->irq) {
- ret = request_threaded_irq(client->irq,
- NULL,
- &ad774x_event_handler,
- IRQF_TRIGGER_FALLING,
- "ad774x",
- indio_dev);
- if (ret)
- goto error_free_dev;
- }
-
- ret = iio_device_register(indio_dev);
- if (ret)
- goto error_free_irq;
-
- dev_err(&client->dev, "%s capacitive sensor registered, irq: %d\n", id->name, client->irq);
-
- return 0;
-
-error_free_irq:
- free_irq(client->irq, indio_dev);
-error_free_dev:
- iio_free_device(indio_dev);
-error_ret:
- return ret;
-}
-
-static int __devexit ad774x_remove(struct i2c_client *client)
-{
- struct iio_dev *indio_dev = i2c_get_clientdata(client);
-
- if (client->irq)
- free_irq(client->irq, indio_dev);
- iio_device_unregister(indio_dev);
-
- return 0;
-}
-
-static const struct i2c_device_id ad774x_id[] = {
- { "ad7745", 0 },
- { "ad7746", 0 },
- { "ad7747", 0 },
- {}
-};
-
-MODULE_DEVICE_TABLE(i2c, ad774x_id);
-
-static struct i2c_driver ad774x_driver = {
- .driver = {
- .name = "ad774x",
- },
- .probe = ad774x_probe,
- .remove = __devexit_p(ad774x_remove),
- .id_table = ad774x_id,
-};
-
-static __init int ad774x_init(void)
-{
- return i2c_add_driver(&ad774x_driver);
-}
-
-static __exit void ad774x_exit(void)
-{
- i2c_del_driver(&ad774x_driver);
-}
-
-MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
-MODULE_DESCRIPTION("Analog Devices ad7745/6/7 capacitive sensor driver");
-MODULE_LICENSE("GPL v2");
-
-module_init(ad774x_init);
-module_exit(ad774x_exit);
--- /dev/null
+/*
+ * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
+ *
+ * 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/i2c.h>
+#include <linux/delay.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+
+#include "ad7746.h"
+
+/*
+ * AD7746 Register Definition
+ */
+
+#define AD7746_REG_STATUS 0
+#define AD7746_REG_CAP_DATA_HIGH 1
+#define AD7746_REG_CAP_DATA_MID 2
+#define AD7746_REG_CAP_DATA_LOW 3
+#define AD7746_REG_VT_DATA_HIGH 4
+#define AD7746_REG_VT_DATA_MID 5
+#define AD7746_REG_VT_DATA_LOW 6
+#define AD7746_REG_CAP_SETUP 7
+#define AD7746_REG_VT_SETUP 8
+#define AD7746_REG_EXC_SETUP 9
+#define AD7746_REG_CFG 10
+#define AD7746_REG_CAPDACA 11
+#define AD7746_REG_CAPDACB 12
+#define AD7746_REG_CAP_OFFH 13
+#define AD7746_REG_CAP_OFFL 14
+#define AD7746_REG_CAP_GAINH 15
+#define AD7746_REG_CAP_GAINL 16
+#define AD7746_REG_VOLT_GAINH 17
+#define AD7746_REG_VOLT_GAINL 18
+
+/* Status Register Bit Designations (AD7746_REG_STATUS) */
+#define AD7746_STATUS_EXCERR (1 << 3)
+#define AD7746_STATUS_RDY (1 << 2)
+#define AD7746_STATUS_RDYVT (1 << 1)
+#define AD7746_STATUS_RDYCAP (1 << 0)
+
+/* Capacitive Channel Setup Register Bit Designations (AD7746_REG_CAP_SETUP) */
+#define AD7746_CAPSETUP_CAPEN (1 << 7)
+#define AD7746_CAPSETUP_CIN2 (1 << 6) /* AD7746 only */
+#define AD7746_CAPSETUP_CAPDIFF (1 << 5)
+#define AD7746_CAPSETUP_CACHOP (1 << 0)
+
+/* Voltage/Temperature Setup Register Bit Designations (AD7746_REG_VT_SETUP) */
+#define AD7746_VTSETUP_VTEN (1 << 7)
+#define AD7746_VTSETUP_VTMD_INT_TEMP (0 << 5)
+#define AD7746_VTSETUP_VTMD_EXT_TEMP (1 << 5)
+#define AD7746_VTSETUP_VTMD_VDD_MON (2 << 5)
+#define AD7746_VTSETUP_VTMD_EXT_VIN (3 << 5)
+#define AD7746_VTSETUP_EXTREF (1 << 4)
+#define AD7746_VTSETUP_VTSHORT (1 << 1)
+#define AD7746_VTSETUP_VTCHOP (1 << 0)
+
+/* Excitation Setup Register Bit Designations (AD7746_REG_EXC_SETUP) */
+#define AD7746_EXCSETUP_CLKCTRL (1 << 7)
+#define AD7746_EXCSETUP_EXCON (1 << 6)
+#define AD7746_EXCSETUP_EXCB (1 << 5)
+#define AD7746_EXCSETUP_NEXCB (1 << 4)
+#define AD7746_EXCSETUP_EXCA (1 << 3)
+#define AD7746_EXCSETUP_NEXCA (1 << 2)
+#define AD7746_EXCSETUP_EXCLVL(x) (((x) & 0x3) << 0)
+
+/* Config Register Bit Designations (AD7746_REG_CFG) */
+#define AD7746_CONF_VTFS(x) ((x) << 6)
+#define AD7746_CONF_CAPFS(x) ((x) << 3)
+#define AD7746_CONF_MODE_IDLE (0 << 0)
+#define AD7746_CONF_MODE_CONT_CONV (1 << 0)
+#define AD7746_CONF_MODE_SINGLE_CONV (2 << 0)
+#define AD7746_CONF_MODE_PWRDN (3 << 0)
+#define AD7746_CONF_MODE_OFFS_CAL (5 << 0)
+#define AD7746_CONF_MODE_GAIN_CAL (6 << 0)
+
+/* CAPDAC Register Bit Designations (AD7746_REG_CAPDACx) */
+#define AD7746_CAPDAC_DACEN (1 << 7)
+#define AD7746_CAPDAC_DACP(x) ((x) & 0x7F)
+
+/*
+ * struct ad7746_chip_info - chip specifc information
+ */
+
+struct ad7746_chip_info {
+ struct i2c_client *client;
+ /*
+ * Capacitive channel digital filter setup;
+ * conversion time/update rate setup per channel
+ */
+ u8 config;
+ u8 cap_setup;
+ u8 vt_setup;
+ u8 capdac[2][2];
+ s8 capdac_set;
+};
+
+enum ad7746_chan {
+ VIN,
+ VIN_VDD,
+ TEMP_INT,
+ TEMP_EXT,
+ CIN1,
+ CIN1_DIFF,
+ CIN2,
+ CIN2_DIFF,
+};
+
+static const struct iio_chan_spec ad7746_channels[] = {
+ [VIN] = {
+ .type = IIO_VOLTAGE,
+ .indexed = 1,
+ .channel = 0,
+ .info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED),
+ .address = AD7746_REG_VT_DATA_HIGH << 8 |
+ AD7746_VTSETUP_VTMD_EXT_VIN,
+ },
+ [VIN_VDD] = {
+ .type = IIO_VOLTAGE,
+ .indexed = 1,
+ .channel = 1,
+ .extend_name = "supply",
+ .info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED),
+ .address = AD7746_REG_VT_DATA_HIGH << 8 |
+ AD7746_VTSETUP_VTMD_VDD_MON,
+ },
+ [TEMP_INT] = {
+ .type = IIO_TEMP,
+ .indexed = 1,
+ .channel = 0,
+ .processed_val = IIO_PROCESSED,
+ .address = AD7746_REG_VT_DATA_HIGH << 8 |
+ AD7746_VTSETUP_VTMD_INT_TEMP,
+ },
+ [TEMP_EXT] = {
+ .type = IIO_TEMP,
+ .indexed = 1,
+ .channel = 1,
+ .processed_val = IIO_PROCESSED,
+ .address = AD7746_REG_VT_DATA_HIGH << 8 |
+ AD7746_VTSETUP_VTMD_EXT_TEMP,
+ },
+ [CIN1] = {
+ .type = IIO_CAPACITANCE,
+ .indexed = 1,
+ .channel = 0,
+ .info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+ (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+ (1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+ (1 << IIO_CHAN_INFO_SCALE_SHARED),
+ .address = AD7746_REG_CAP_DATA_HIGH << 8,
+ },
+ [CIN1_DIFF] = {
+ .type = IIO_CAPACITANCE,
+ .differential = 1,
+ .indexed = 1,
+ .channel = 0,
+ .channel2 = 2,
+ .info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+ (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+ (1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+ (1 << IIO_CHAN_INFO_SCALE_SHARED),
+ .address = AD7746_REG_CAP_DATA_HIGH << 8 |
+ AD7746_CAPSETUP_CAPDIFF
+ },
+ [CIN2] = {
+ .type = IIO_CAPACITANCE,
+ .indexed = 1,
+ .channel = 1,
+ .info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+ (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+ (1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+ (1 << IIO_CHAN_INFO_SCALE_SHARED),
+ .address = AD7746_REG_CAP_DATA_HIGH << 8 |
+ AD7746_CAPSETUP_CIN2,
+ },
+ [CIN2_DIFF] = {
+ .type = IIO_CAPACITANCE,
+ .differential = 1,
+ .indexed = 1,
+ .channel = 1,
+ .channel2 = 3,
+ .info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+ (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+ (1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+ (1 << IIO_CHAN_INFO_SCALE_SHARED),
+ .address = AD7746_REG_CAP_DATA_HIGH << 8 |
+ AD7746_CAPSETUP_CAPDIFF | AD7746_CAPSETUP_CIN2,
+ }
+};
+
+/* Values are Update Rate (Hz), Conversion Time (ms) + 1*/
+static const unsigned char ad7746_vt_filter_rate_table[][2] = {
+ {50, 20 + 1}, {31, 32 + 1}, {16, 62 + 1}, {8, 122 + 1},
+};
+
+static const unsigned char ad7746_cap_filter_rate_table[][2] = {
+ {91, 11 + 1}, {84, 12 + 1}, {50, 20 + 1}, {26, 38 + 1},
+ {16, 62 + 1}, {13, 77 + 1}, {11, 92 + 1}, {9, 110 + 1},
+};
+
+static int ad7746_select_channel(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan)
+{
+ struct ad7746_chip_info *chip = iio_priv(indio_dev);
+ int ret, delay;
+ u8 vt_setup, cap_setup;
+
+ switch (chan->type) {
+ case IIO_CAPACITANCE:
+ cap_setup = (chan->address & 0xFF) | AD7746_CAPSETUP_CAPEN;
+ vt_setup = chip->vt_setup & ~AD7746_VTSETUP_VTEN;
+ delay = ad7746_cap_filter_rate_table[(chip->config >> 3) &
+ 0x7][1];
+
+ if (chip->capdac_set != chan->channel) {
+ ret = i2c_smbus_write_byte_data(chip->client,
+ AD7746_REG_CAPDACA,
+ chip->capdac[chan->channel][0]);
+ if (ret < 0)
+ return ret;
+ ret = i2c_smbus_write_byte_data(chip->client,
+ AD7746_REG_CAPDACB,
+ chip->capdac[chan->channel][1]);
+ if (ret < 0)
+ return ret;
+
+ chip->capdac_set = chan->channel;
+ }
+ break;
+ case IIO_VOLTAGE:
+ case IIO_TEMP:
+ vt_setup = (chan->address & 0xFF) | AD7746_VTSETUP_VTEN;
+ cap_setup = chip->cap_setup & ~AD7746_CAPSETUP_CAPEN;
+ delay = ad7746_cap_filter_rate_table[(chip->config >> 6) &
+ 0x3][1];
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (chip->cap_setup != cap_setup) {
+ ret = i2c_smbus_write_byte_data(chip->client,
+ AD7746_REG_CAP_SETUP,
+ cap_setup);
+ if (ret < 0)
+ return ret;
+
+ chip->cap_setup = cap_setup;
+ }
+
+ if (chip->vt_setup != vt_setup) {
+ ret = i2c_smbus_write_byte_data(chip->client,
+ AD7746_REG_VT_SETUP,
+ vt_setup);
+ if (ret < 0)
+ return ret;
+
+ chip->vt_setup = vt_setup;
+ }
+
+ return delay;
+}
+
+static inline ssize_t ad7746_start_calib(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len,
+ u8 regval)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad7746_chip_info *chip = iio_priv(indio_dev);
+ bool doit;
+ int ret, timeout = 10;
+
+ ret = strtobool(buf, &doit);
+ if (ret < 0)
+ return ret;
+
+ if (!doit)
+ return 0;
+
+ mutex_lock(&indio_dev->mlock);
+ regval |= chip->config;
+ ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG, regval);
+ if (ret < 0) {
+ mutex_unlock(&indio_dev->mlock);
+ return ret;
+ }
+
+ do {
+ msleep(20);
+ ret = i2c_smbus_read_byte_data(chip->client, AD7746_REG_CFG);
+ if (ret < 0) {
+ mutex_unlock(&indio_dev->mlock);
+ return ret;
+ }
+ } while ((ret == regval) && timeout--);
+
+ mutex_unlock(&indio_dev->mlock);
+
+ return len;
+}
+
+static ssize_t ad7746_start_offset_calib(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ int ret = ad7746_select_channel(indio_dev,
+ &ad7746_channels[to_iio_dev_attr(attr)->address]);
+ if (ret < 0)
+ return ret;
+
+ return ad7746_start_calib(dev, attr, buf, len,
+ AD7746_CONF_MODE_OFFS_CAL);
+}
+
+static ssize_t ad7746_start_gain_calib(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ int ret = ad7746_select_channel(indio_dev,
+ &ad7746_channels[to_iio_dev_attr(attr)->address]);
+ if (ret < 0)
+ return ret;
+
+ return ad7746_start_calib(dev, attr, buf, len,
+ AD7746_CONF_MODE_GAIN_CAL);
+}
+
+static IIO_DEVICE_ATTR(in_capacitance0_calibbias_calibration,
+ S_IWUSR, NULL, ad7746_start_offset_calib, CIN1);
+static IIO_DEVICE_ATTR(in_capacitance1_calibbias_calibration,
+ S_IWUSR, NULL, ad7746_start_offset_calib, CIN2);
+static IIO_DEVICE_ATTR(in_capacitance0_calibscale_calibration,
+ S_IWUSR, NULL, ad7746_start_gain_calib, CIN1);
+static IIO_DEVICE_ATTR(in_capacitance1_calibscale_calibration,
+ S_IWUSR, NULL, ad7746_start_gain_calib, CIN2);
+static IIO_DEVICE_ATTR(in_voltage0_calibscale_calibration,
+ S_IWUSR, NULL, ad7746_start_gain_calib, VIN);
+
+static ssize_t ad7746_show_cap_filter_rate_setup(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad7746_chip_info *chip = iio_priv(indio_dev);
+
+ return sprintf(buf, "%d\n", ad7746_cap_filter_rate_table[
+ (chip->config >> 3) & 0x7][0]);
+}
+
+static ssize_t ad7746_store_cap_filter_rate_setup(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad7746_chip_info *chip = iio_priv(indio_dev);
+ u8 data;
+ int ret, i;
+
+ ret = kstrtou8(buf, 10, &data);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < ARRAY_SIZE(ad7746_cap_filter_rate_table); i++)
+ if (data >= ad7746_cap_filter_rate_table[i][0])
+ break;
+
+ if (i >= ARRAY_SIZE(ad7746_cap_filter_rate_table))
+ i = ARRAY_SIZE(ad7746_cap_filter_rate_table) - 1;
+
+ mutex_lock(&indio_dev->mlock);
+ chip->config &= ~AD7746_CONF_CAPFS(0x7);
+ chip->config |= AD7746_CONF_CAPFS(i);
+ mutex_unlock(&indio_dev->mlock);
+
+ return len;
+}
+
+static ssize_t ad7746_show_vt_filter_rate_setup(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad7746_chip_info *chip = iio_priv(indio_dev);
+
+ return sprintf(buf, "%d\n", ad7746_vt_filter_rate_table[
+ (chip->config >> 6) & 0x3][0]);
+}
+
+static ssize_t ad7746_store_vt_filter_rate_setup(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad7746_chip_info *chip = iio_priv(indio_dev);
+ u8 data;
+ int ret, i;
+
+ ret = kstrtou8(buf, 10, &data);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < ARRAY_SIZE(ad7746_vt_filter_rate_table); i++)
+ if (data >= ad7746_vt_filter_rate_table[i][0])
+ break;
+
+ if (i >= ARRAY_SIZE(ad7746_vt_filter_rate_table))
+ i = ARRAY_SIZE(ad7746_vt_filter_rate_table) - 1;
+
+ mutex_lock(&indio_dev->mlock);
+ chip->config &= ~AD7746_CONF_VTFS(0x3);
+ chip->config |= AD7746_CONF_VTFS(i);
+ mutex_unlock(&indio_dev->mlock);
+
+ return len;
+}
+
+static IIO_DEVICE_ATTR(in_capacitance_sampling_frequency,
+ S_IRUGO | S_IWUSR, ad7746_show_cap_filter_rate_setup,
+ ad7746_store_cap_filter_rate_setup, 0);
+
+static IIO_DEVICE_ATTR(in_voltage_sampling_frequency,
+ S_IRUGO | S_IWUSR, ad7746_show_vt_filter_rate_setup,
+ ad7746_store_vt_filter_rate_setup, 0);
+
+static IIO_CONST_ATTR(in_voltage_sampling_frequency_available, "50 31 16 8");
+static IIO_CONST_ATTR(in_capacitance_sampling_frequency_available,
+ "91 84 50 26 16 13 11 9");
+
+static struct attribute *ad7746_attributes[] = {
+ &iio_dev_attr_in_capacitance_sampling_frequency.dev_attr.attr,
+ &iio_dev_attr_in_voltage_sampling_frequency.dev_attr.attr,
+ &iio_dev_attr_in_capacitance0_calibbias_calibration.dev_attr.attr,
+ &iio_dev_attr_in_capacitance0_calibscale_calibration.dev_attr.attr,
+ &iio_dev_attr_in_capacitance1_calibscale_calibration.dev_attr.attr,
+ &iio_dev_attr_in_capacitance1_calibbias_calibration.dev_attr.attr,
+ &iio_dev_attr_in_voltage0_calibscale_calibration.dev_attr.attr,
+ &iio_const_attr_in_voltage_sampling_frequency_available.dev_attr.attr,
+ &iio_const_attr_in_capacitance_sampling_frequency_available.
+ dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ad7746_attribute_group = {
+ .attrs = ad7746_attributes,
+};
+
+static int ad7746_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val,
+ int val2,
+ long mask)
+{
+ struct ad7746_chip_info *chip = iio_priv(indio_dev);
+ int ret, reg;
+
+ mutex_lock(&indio_dev->mlock);
+
+ switch (mask) {
+ case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
+ if (val != 1) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ val = (val2 * 1024) / 15625;
+
+ switch (chan->type) {
+ case IIO_CAPACITANCE:
+ reg = AD7746_REG_CAP_GAINH;
+ break;
+ case IIO_VOLTAGE:
+ reg = AD7746_REG_VOLT_GAINH;
+ break;
+ default:
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = i2c_smbus_write_word_data(chip->client, reg, swab16(val));
+ if (ret < 0)
+ goto out;
+
+ ret = 0;
+ break;
+ case (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED):
+ if ((val < 0) | (val > 0xFFFF)) {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = i2c_smbus_write_word_data(chip->client,
+ AD7746_REG_CAP_OFFH, swab16(val));
+ if (ret < 0)
+ goto out;
+
+ ret = 0;
+ break;
+ case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
+ if ((val < 0) | (val > 43008000)) { /* 21pF */
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* CAPDAC Scale = 21pF_typ / 127
+ * CIN Scale = 8.192pF / 2^24
+ * Offset Scale = CAPDAC Scale / CIN Scale = 338646
+ * */
+
+ val /= 338646;
+
+ chip->capdac[chan->channel][chan->differential] = (val > 0 ?
+ AD7746_CAPDAC_DACP(val) | AD7746_CAPDAC_DACEN : 0);
+
+ ret = i2c_smbus_write_byte_data(chip->client,
+ AD7746_REG_CAPDACA,
+ chip->capdac[chan->channel][0]);
+ if (ret < 0)
+ goto out;
+ ret = i2c_smbus_write_byte_data(chip->client,
+ AD7746_REG_CAPDACB,
+ chip->capdac[chan->channel][1]);
+ if (ret < 0)
+ goto out;
+
+ chip->capdac_set = chan->channel;
+
+ ret = 0;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+out:
+ mutex_unlock(&indio_dev->mlock);
+ return ret;
+}
+
+static int ad7746_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2,
+ long mask)
+{
+ struct ad7746_chip_info *chip = iio_priv(indio_dev);
+ int ret, delay;
+ u8 regval, reg;
+
+ union {
+ u32 d32;
+ u8 d8[4];
+ } data;
+
+ mutex_lock(&indio_dev->mlock);
+
+ switch (mask) {
+ case 0:
+ ret = ad7746_select_channel(indio_dev, chan);
+ if (ret < 0)
+ goto out;
+ delay = ret;
+
+ regval = chip->config | AD7746_CONF_MODE_SINGLE_CONV;
+ ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG,
+ regval);
+ if (ret < 0)
+ goto out;
+
+ msleep(delay);
+ /* Now read the actual register */
+
+ ret = i2c_smbus_read_i2c_block_data(chip->client,
+ chan->address >> 8, 3, &data.d8[1]);
+
+ if (ret < 0)
+ goto out;
+
+ *val = (be32_to_cpu(data.d32) & 0xFFFFFF) - 0x800000;
+
+ switch (chan->type) {
+ case IIO_TEMP:
+ /* temperature in milli degrees Celsius
+ * T = ((*val / 2048) - 4096) * 1000
+ */
+ *val = (*val * 125) / 256;
+ break;
+ case IIO_VOLTAGE:
+ if (chan->channel == 1) /* supply_raw*/
+ *val = *val * 6;
+ break;
+ default:
+ break;
+ }
+
+ ret = IIO_VAL_INT;
+ break;
+ case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
+ switch (chan->type) {
+ case IIO_CAPACITANCE:
+ reg = AD7746_REG_CAP_GAINH;
+ break;
+ case IIO_VOLTAGE:
+ reg = AD7746_REG_VOLT_GAINH;
+ break;
+ default:
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = i2c_smbus_read_word_data(chip->client, reg);
+ if (ret < 0)
+ goto out;
+ /* 1 + gain_val / 2^16 */
+ *val = 1;
+ *val2 = (15625 * swab16(ret)) / 1024;
+
+ ret = IIO_VAL_INT_PLUS_MICRO;
+ break;
+ case (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED):
+ ret = i2c_smbus_read_word_data(chip->client,
+ AD7746_REG_CAP_OFFH);
+ if (ret < 0)
+ goto out;
+ *val = swab16(ret);
+
+ ret = IIO_VAL_INT;
+ break;
+ case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
+ *val = AD7746_CAPDAC_DACP(chip->capdac[chan->channel]
+ [chan->differential]) * 338646;
+
+ ret = IIO_VAL_INT;
+ break;
+ case (1 << IIO_CHAN_INFO_SCALE_SHARED):
+ switch (chan->type) {
+ case IIO_CAPACITANCE:
+ /* 8.192pf / 2^24 */
+ *val2 = 488;
+ *val = 0;
+ break;
+ case IIO_VOLTAGE:
+ /* 1170mV / 2^23 */
+ *val2 = 139475;
+ *val = 0;
+ break;
+ default:
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = IIO_VAL_INT_PLUS_NANO;
+ break;
+ default:
+ ret = -EINVAL;
+ };
+out:
+ mutex_unlock(&indio_dev->mlock);
+ return ret;
+}
+
+static const struct iio_info ad7746_info = {
+ .attrs = &ad7746_attribute_group,
+ .read_raw = &ad7746_read_raw,
+ .write_raw = &ad7746_write_raw,
+ .driver_module = THIS_MODULE,
+};
+
+/*
+ * device probe and remove
+ */
+
+static int __devinit ad7746_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct ad7746_platform_data *pdata = client->dev.platform_data;
+ struct ad7746_chip_info *chip;
+ struct iio_dev *indio_dev;
+ int ret = 0;
+ unsigned char regval = 0;
+
+ indio_dev = iio_allocate_device(sizeof(*chip));
+ if (indio_dev == NULL) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ chip = iio_priv(indio_dev);
+ /* this is only used for device removal purposes */
+ i2c_set_clientdata(client, indio_dev);
+
+ chip->client = client;
+ chip->capdac_set = -1;
+
+ /* Establish that the iio_dev is a child of the i2c device */
+ indio_dev->name = id->name;
+ indio_dev->dev.parent = &client->dev;
+ indio_dev->info = &ad7746_info;
+ indio_dev->channels = ad7746_channels;
+ if (id->driver_data == 7746)
+ indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
+ else
+ indio_dev->num_channels = ARRAY_SIZE(ad7746_channels) - 2;
+ indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ if (pdata) {
+ if (pdata->exca_en) {
+ if (pdata->exca_inv_en)
+ regval |= AD7746_EXCSETUP_NEXCA;
+ else
+ regval |= AD7746_EXCSETUP_EXCA;
+ }
+
+ if (pdata->excb_en) {
+ if (pdata->excb_inv_en)
+ regval |= AD7746_EXCSETUP_NEXCB;
+ else
+ regval |= AD7746_EXCSETUP_EXCB;
+ }
+
+ regval |= AD7746_EXCSETUP_EXCLVL(pdata->exclvl);
+ } else {
+ dev_warn(&client->dev, "No platform data? using default\n");
+ regval = AD7746_EXCSETUP_EXCA | AD7746_EXCSETUP_EXCB |
+ AD7746_EXCSETUP_EXCLVL(3);
+ }
+
+ ret = i2c_smbus_write_byte_data(chip->client,
+ AD7746_REG_EXC_SETUP, regval);
+ if (ret < 0)
+ goto error_free_dev;
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto error_free_dev;
+
+ dev_info(&client->dev, "%s capacitive sensor registered\n", id->name);
+
+ return 0;
+
+error_free_dev:
+ iio_free_device(indio_dev);
+error_ret:
+ return ret;
+}
+
+static int __devexit ad7746_remove(struct i2c_client *client)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+ iio_device_unregister(indio_dev);
+
+ return 0;
+}
+
+static const struct i2c_device_id ad7746_id[] = {
+ { "ad7745", 7745 },
+ { "ad7746", 7746 },
+ { "ad7747", 7747 },
+ {}
+};
+
+MODULE_DEVICE_TABLE(i2c, ad7746_id);
+
+static struct i2c_driver ad7746_driver = {
+ .driver = {
+ .name = KBUILD_MODNAME,
+ },
+ .probe = ad7746_probe,
+ .remove = __devexit_p(ad7746_remove),
+ .id_table = ad7746_id,
+};
+
+static __init int ad7746_init(void)
+{
+ return i2c_add_driver(&ad7746_driver);
+}
+
+static __exit void ad7746_exit(void)
+{
+ i2c_del_driver(&ad7746_driver);
+}
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7746/5/7 capacitive sensor driver");
+MODULE_LICENSE("GPL v2");
+
+module_init(ad7746_init);
+module_exit(ad7746_exit);
--- /dev/null
+/*
+ * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#ifndef IIO_CDC_AD7746_H_
+#define IIO_CDC_AD7746_H_
+
+/*
+ * TODO: struct ad7746_platform_data needs to go into include/linux/iio
+ */
+
+#define AD7466_EXCLVL_0 0 /* +-VDD/8 */
+#define AD7466_EXCLVL_1 1 /* +-VDD/4 */
+#define AD7466_EXCLVL_2 2 /* +-VDD * 3/8 */
+#define AD7466_EXCLVL_3 3 /* +-VDD/2 */
+
+struct ad7746_platform_data {
+ unsigned char exclvl; /*Excitation Voltage Level */
+ bool exca_en; /* enables EXCA pin as the excitation output */
+ bool exca_inv_en; /* enables /EXCA pin as the excitation output */
+ bool excb_en; /* enables EXCB pin as the excitation output */
+ bool excb_inv_en; /* enables /EXCB pin as the excitation output */
+};
+
+#endif /* IIO_CDC_AD7746_H_ */