staging: iio: adc: new driver for AD7152/3 devices

Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/adc/Kconfig

@@ -34,6 +34,13 @@ config AD7150
 	  Say yes here to build support for Analog Devices capacitive sensors.
 	  (ad7150, ad7151, ad7156) Provides direct access via sysfs.
 
+config AD7152
+	tristate "Analog Devices ad7152/3 capacitive sensor driver"
+	depends on I2C
+	help
+	  Say yes here to build support for Analog Devices capacitive sensors.
+	  (ad7152, ad7153) Provides direct access via sysfs.
+
 config AD799X
 	tristate "Analog Devices AD799x ADC driver"
 	depends on I2C

drivers/staging/iio/adc/Makefile

@@ -16,3 +16,4 @@ ad7476-$(CONFIG_IIO_RING_BUFFER) += ad7476_ring.o
 obj-$(CONFIG_AD7476) += ad7476.o
 
 obj-$(CONFIG_AD7150) += ad7150.o
+obj-$(CONFIG_AD7152) += ad7152.o

drivers/staging/iio/adc/ad7152.c

+/*
+ * AD7152 capacitive sensor driver supporting AD7152/3
+ *
+ * Copyright 2010 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/gpio.h>
+#include <linux/workqueue.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/rtc.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+
+/*
+ * AD7152 registers definition
+ */
+
+#define AD7152_STATUS              0
+#define AD7152_STATUS_RDY1         (1 << 0)
+#define AD7152_STATUS_RDY2         (1 << 1)
+#define AD7152_CH1_DATA_HIGH       1
+#define AD7152_CH1_DATA_LOW        2
+#define AD7152_CH2_DATA_HIGH       3
+#define AD7152_CH2_DATA_LOW        4
+#define AD7152_CH1_OFFS_HIGH       5
+#define AD7152_CH1_OFFS_LOW        6
+#define AD7152_CH2_OFFS_HIGH       7
+#define AD7152_CH2_OFFS_LOW        8
+#define AD7152_CH1_GAIN_HIGH       9
+#define AD7152_CH1_GAIN_LOW        10
+#define AD7152_CH1_SETUP           11
+#define AD7152_CH2_GAIN_HIGH       12
+#define AD7152_CH2_GAIN_LOW        13
+#define AD7152_CH2_SETUP           14
+#define AD7152_CFG                 15
+#define AD7152_RESEVERD            16
+#define AD7152_CAPDAC_POS          17
+#define AD7152_CAPDAC_NEG          18
+#define AD7152_CFG2                26
+
+#define AD7152_MAX_CONV_MODE       6
+
+/*
+ * struct ad7152_chip_info - chip specifc information
+ */
+
+struct ad7152_chip_info {
+	const char *name;
+	struct i2c_client *client;
+	struct iio_dev *indio_dev;
+	u16 ch1_offset;     /* Channel 1 offset calibration coefficient */
+	u16 ch1_gain;       /* Channel 1 gain coefficient */
+	u8  ch1_setup;
+	u16 ch2_offset;     /* Channel 2 offset calibration coefficient */
+	u16 ch2_gain;       /* Channel 1 gain coefficient */
+	u8  ch2_setup;
+	u8  filter_rate_setup; /* Capacitive channel digital filter setup; conversion time/update rate setup per channel */
+	char *conversion_mode;
+};
+
+struct ad7152_conversion_mode {
+	char *name;
+	u8 reg_cfg;
+};
+
+struct ad7152_conversion_mode ad7152_conv_mode_table[AD7152_MAX_CONV_MODE] = {
+	{ "idle", 0 },
+	{ "continuous-conversion", 1 },
+	{ "single-conversion", 2 },
+	{ "power-down", 3 },
+	{ "offset-calibration", 5 },
+	{ "gain-calibration", 6 },
+};
+
+/*
+ * ad7152 register access by I2C
+ */
+
+static int ad7152_i2c_read(struct ad7152_chip_info *chip, u8 reg, u8 *data, int len)
+{
+	struct i2c_client *client = chip->client;
+	int ret;
+
+	ret = i2c_master_send(client, &reg, 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;
+}
+
+static int ad7152_i2c_write(struct ad7152_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_CH1_OFFSET(_mode, _show, _store)		\
+	IIO_DEVICE_ATTR(ch1_offset, _mode, _show, _store, 0)
+#define IIO_DEV_ATTR_CH2_OFFSET(_mode, _show, _store)		\
+	IIO_DEVICE_ATTR(ch2_offset, _mode, _show, _store, 0)
+#define IIO_DEV_ATTR_CH1_GAIN(_mode, _show, _store)		\
+	IIO_DEVICE_ATTR(ch1_gain, _mode, _show, _store, 0)
+#define IIO_DEV_ATTR_CH2_GAIN(_mode, _show, _store)		\
+	IIO_DEVICE_ATTR(ch2_gain, _mode, _show, _store, 0)
+#define IIO_DEV_ATTR_CH1_VALUE(_show)		\
+	IIO_DEVICE_ATTR(ch1_value, S_IRUGO, _show, NULL, 0)
+#define IIO_DEV_ATTR_CH2_VALUE(_show)		\
+	IIO_DEVICE_ATTR(ch2_value, S_IRUGO, _show, NULL, 0)
+#define IIO_DEV_ATTR_CH1_SETUP(_mode, _show, _store)		\
+	IIO_DEVICE_ATTR(ch1_setup, _mode, _show, _store, 0)
+#define IIO_DEV_ATTR_CH2_SETUP(_mode, _show, _store)              \
+	IIO_DEVICE_ATTR(ch2_setup, _mode, _show, _store, 0)
+#define IIO_DEV_ATTR_FILTER_RATE_SETUP(_mode, _show, _store)              \
+	IIO_DEVICE_ATTR(filter_rate_setup, _mode, _show, _store, 0)
+
+static ssize_t ad7152_show_conversion_modes(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	int i;
+	int len = 0;
+
+	for (i = 0; i < AD7152_MAX_CONV_MODE; i++)
+		len += sprintf(buf + len, "%s ", ad7152_conv_mode_table[i].name);
+
+	len += sprintf(buf + len, "\n");
+
+	return len;
+}
+
+static IIO_DEV_ATTR_AVAIL_CONVERSION_MODES(ad7152_show_conversion_modes);
+
+static ssize_t ad7152_show_ch1_value(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+	u8 data[2];
+
+	ad7152_i2c_read(chip, AD7152_CH1_DATA_HIGH, data, 2);
+	return sprintf(buf, "%d\n", ((int)data[0] << 8) | data[1]);
+}
+
+static IIO_DEV_ATTR_CH1_VALUE(ad7152_show_ch1_value);
+
+static ssize_t ad7152_show_ch2_value(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+	u8 data[2];
+
+	ad7152_i2c_read(chip, AD7152_CH2_DATA_HIGH, data, 2);
+	return sprintf(buf, "%d\n", ((int)data[0] << 8) | data[1]);
+}
+
+static IIO_DEV_ATTR_CH2_VALUE(ad7152_show_ch2_value);
+
+static ssize_t ad7152_show_conversion_mode(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+
+	return sprintf(buf, "%s\n", chip->conversion_mode);
+}
+
+static ssize_t ad7152_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 ad7152_chip_info *chip = dev_info->dev_data;
+	u8 cfg;
+	int i;
+
+	ad7152_i2c_read(chip, AD7152_CFG, &cfg, 1);
+
+	for (i = 0; i < AD7152_MAX_CONV_MODE; i++)
+		if (strncmp(buf, ad7152_conv_mode_table[i].name,
+				strlen(ad7152_conv_mode_table[i].name) - 1) == 0) {
+			chip->conversion_mode = ad7152_conv_mode_table[i].name;
+			cfg |= 0x18 | ad7152_conv_mode_table[i].reg_cfg;
+			ad7152_i2c_write(chip, AD7152_CFG, cfg);
+			return len;
+		}
+
+	dev_err(dev, "not supported conversion mode\n");
+
+	return -EINVAL;
+}
+
+static IIO_DEV_ATTR_CONVERSION_MODE(S_IRUGO | S_IWUSR,
+		ad7152_show_conversion_mode,
+		ad7152_store_conversion_mode);
+
+static ssize_t ad7152_show_ch1_offset(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+
+	return sprintf(buf, "%d\n", chip->ch1_offset);
+}
+
+static ssize_t ad7152_store_ch1_offset(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+	unsigned long data;
+	int ret;
+
+	ret = strict_strtoul(buf, 10, &data);
+
+	if ((!ret) && (data < 0x10000)) {
+		ad7152_i2c_write(chip, AD7152_CH1_OFFS_HIGH, data >> 8);
+		ad7152_i2c_write(chip, AD7152_CH1_OFFS_LOW, data);
+		chip->ch1_offset = data;
+		return len;
+	}
+
+	return -EINVAL;
+}
+
+static IIO_DEV_ATTR_CH1_OFFSET(S_IRUGO | S_IWUSR,
+		ad7152_show_ch1_offset,
+		ad7152_store_ch1_offset);
+
+static ssize_t ad7152_show_ch2_offset(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+
+	return sprintf(buf, "%d\n", chip->ch2_offset);
+}
+
+static ssize_t ad7152_store_ch2_offset(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+	unsigned long data;
+	int ret;
+
+	ret = strict_strtoul(buf, 10, &data);
+
+	if ((!ret) && (data < 0x10000)) {
+		ad7152_i2c_write(chip, AD7152_CH2_OFFS_HIGH, data >> 8);
+		ad7152_i2c_write(chip, AD7152_CH2_OFFS_LOW, data);
+		chip->ch2_offset = data;
+		return len;
+	}
+
+	return -EINVAL;
+}
+
+static IIO_DEV_ATTR_CH2_OFFSET(S_IRUGO | S_IWUSR,
+		ad7152_show_ch2_offset,
+		ad7152_store_ch2_offset);
+
+static ssize_t ad7152_show_ch1_gain(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+
+	return sprintf(buf, "%d\n", chip->ch1_gain);
+}
+
+static ssize_t ad7152_store_ch1_gain(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+	unsigned long data;
+	int ret;
+
+	ret = strict_strtoul(buf, 10, &data);
+
+	if ((!ret) && (data < 0x10000)) {
+		ad7152_i2c_write(chip, AD7152_CH1_GAIN_HIGH, data >> 8);
+		ad7152_i2c_write(chip, AD7152_CH1_GAIN_LOW, data);
+		chip->ch1_gain = data;
+		return len;
+	}
+
+	return -EINVAL;
+}
+
+static IIO_DEV_ATTR_CH1_GAIN(S_IRUGO | S_IWUSR,
+		ad7152_show_ch1_gain,
+		ad7152_store_ch1_gain);
+
+static ssize_t ad7152_show_ch2_gain(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+
+	return sprintf(buf, "%d\n", chip->ch2_gain);
+}
+
+static ssize_t ad7152_store_ch2_gain(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+	unsigned long data;
+	int ret;
+
+	ret = strict_strtoul(buf, 10, &data);
+
+	if ((!ret) && (data < 0x10000)) {
+		ad7152_i2c_write(chip, AD7152_CH2_GAIN_HIGH, data >> 8);
+		ad7152_i2c_write(chip, AD7152_CH2_GAIN_LOW, data);
+		chip->ch2_gain = data;
+		return len;
+	}
+
+	return -EINVAL;
+}
+
+static IIO_DEV_ATTR_CH2_GAIN(S_IRUGO | S_IWUSR,
+		ad7152_show_ch2_gain,
+		ad7152_store_ch2_gain);
+
+static ssize_t ad7152_show_ch1_setup(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+
+	return sprintf(buf, "0x%02x\n", chip->ch1_setup);
+}
+
+static ssize_t ad7152_store_ch1_setup(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+	unsigned long data;
+	int ret;
+
+	ret = strict_strtoul(buf, 10, &data);
+
+	if ((!ret) && (data < 0x100)) {
+		ad7152_i2c_write(chip, AD7152_CH1_SETUP, data);
+		chip->ch1_setup = data;
+		return len;
+	}
+
+	return -EINVAL;
+}
+
+static IIO_DEV_ATTR_CH1_SETUP(S_IRUGO | S_IWUSR,
+		ad7152_show_ch1_setup,
+		ad7152_store_ch1_setup);
+
+static ssize_t ad7152_show_ch2_setup(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+
+	return sprintf(buf, "0x%02x\n", chip->ch2_setup);
+}
+
+static ssize_t ad7152_store_ch2_setup(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+	unsigned long data;
+	int ret;
+
+	ret = strict_strtoul(buf, 10, &data);
+
+	if ((!ret) && (data < 0x100)) {
+		ad7152_i2c_write(chip, AD7152_CH2_SETUP, data);
+		chip->ch2_setup = data;
+		return len;
+	}
+
+	return -EINVAL;
+}
+
+static IIO_DEV_ATTR_CH2_SETUP(S_IRUGO | S_IWUSR,
+		ad7152_show_ch2_setup,
+		ad7152_store_ch2_setup);
+
+static ssize_t ad7152_show_filter_rate_setup(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+
+	return sprintf(buf, "0x%02x\n", chip->filter_rate_setup);
+}
+
+static ssize_t ad7152_store_filter_rate_setup(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t len)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+	unsigned long data;
+	int ret;
+
+	ret = strict_strtoul(buf, 10, &data);
+
+	if ((!ret) && (data < 0x100)) {
+		ad7152_i2c_write(chip, AD7152_CFG2, data);
+		chip->filter_rate_setup = data;
+		return len;
+	}
+
+	return -EINVAL;
+}
+
+static IIO_DEV_ATTR_FILTER_RATE_SETUP(S_IRUGO | S_IWUSR,
+		ad7152_show_filter_rate_setup,
+		ad7152_store_filter_rate_setup);
+
+static ssize_t ad7152_show_name(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *dev_info = dev_get_drvdata(dev);
+	struct ad7152_chip_info *chip = dev_info->dev_data;
+	return sprintf(buf, "%s\n", chip->name);
+}
+
+static IIO_DEVICE_ATTR(name, S_IRUGO, ad7152_show_name, NULL, 0);
+
+static struct attribute *ad7152_attributes[] = {
+	&iio_dev_attr_available_conversion_modes.dev_attr.attr,
+	&iio_dev_attr_conversion_mode.dev_attr.attr,
+	&iio_dev_attr_ch1_gain.dev_attr.attr,
+	&iio_dev_attr_ch2_gain.dev_attr.attr,
+	&iio_dev_attr_ch1_offset.dev_attr.attr,
+	&iio_dev_attr_ch2_offset.dev_attr.attr,
+	&iio_dev_attr_ch1_value.dev_attr.attr,
+	&iio_dev_attr_ch2_value.dev_attr.attr,
+	&iio_dev_attr_ch1_setup.dev_attr.attr,
+	&iio_dev_attr_ch2_setup.dev_attr.attr,
+	&iio_dev_attr_filter_rate_setup.dev_attr.attr,
+	&iio_dev_attr_name.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ad7152_attribute_group = {
+	.attrs = ad7152_attributes,
+};
+
+/*
+ * device probe and remove
+ */
+
+static int __devinit ad7152_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
+{
+	int ret = 0;
+	struct ad7152_chip_info *chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+	if (chip == NULL) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+
+	/* this is only used for device removal purposes */
+	i2c_set_clientdata(client, chip);
+
+	chip->client = client;
+	chip->name = id->name;
+
+	chip->indio_dev = iio_allocate_device();
+	if (chip->indio_dev == NULL) {
+		ret = -ENOMEM;
+		goto error_free_chip;
+	}
+
+	/* Echipabilish that the iio_dev is a child of the i2c device */
+	chip->indio_dev->dev.parent = &client->dev;
+	chip->indio_dev->attrs = &ad7152_attribute_group;
+	chip->indio_dev->dev_data = (void *)(chip);
+	chip->indio_dev->driver_module = THIS_MODULE;
+	chip->indio_dev->modes = INDIO_DIRECT_MODE;
+
+	ret = iio_device_register(chip->indio_dev);
+	if (ret)
+		goto error_free_dev;
+
+	dev_err(&client->dev, "%s capacitive sensor registered\n", id->name);
+
+	return 0;
+
+error_free_dev:
+	iio_free_device(chip->indio_dev);
+error_free_chip:
+	kfree(chip);
+error_ret:
+	return ret;
+}
+
+static int __devexit ad7152_remove(struct i2c_client *client)
+{
+	struct ad7152_chip_info *chip = i2c_get_clientdata(client);
+	struct iio_dev *indio_dev = chip->indio_dev;
+
+	if (client->irq && gpio_is_valid(irq_to_gpio(client->irq)) > 0)
+		iio_unregister_interrupt_line(indio_dev, 0);
+	iio_device_unregister(indio_dev);
+	kfree(chip);
+
+	return 0;
+}
+
+static const struct i2c_device_id ad7152_id[] = {
+	{ "ad7152", 0 },
+	{ "ad7153", 0 },
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, ad7152_id);
+
+static struct i2c_driver ad7152_driver = {
+	.driver = {
+		.name = "ad7152",
+	},
+	.probe = ad7152_probe,
+	.remove = __devexit_p(ad7152_remove),
+	.id_table = ad7152_id,
+};
+
+static __init int ad7152_init(void)
+{
+	return i2c_add_driver(&ad7152_driver);
+}
+
+static __exit void ad7152_exit(void)
+{
+	i2c_del_driver(&ad7152_driver);
+}
+
+MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
+MODULE_DESCRIPTION("Analog Devices ad7152/3 capacitive sensor driver");
+MODULE_LICENSE("GPL v2");
+
+module_init(ad7152_init);
+module_exit(ad7152_exit);