1 files changed, 674 insertions, 0 deletions

diff --git a/drivers/staging/iio/adc/ad7745.c b/drivers/staging/iio/adc/ad7745.c
new file mode 100644
index 00000000000..4c13f26aa9a
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7745.c
@@ -0,0 +1,674 @@
+/*
+ * 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 "../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, &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;
+        }
+
+        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(cap_setup, _mode, _show, _store, 0)
+#define IIO_DEV_ATTR_VT_SETUP(_mode, _show, _store)              \
+        IIO_DEVICE_ATTR(in0_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(in0_gain, _mode, _show, _store, 0)
+#define IIO_DEV_ATTR_CAP_OFFS(_mode, _show, _store)             \
+        IIO_DEVICE_ATTR(cap_offs, _mode, _show, _store, 0)
+#define IIO_DEV_ATTR_CAP_GAIN(_mode, _show, _store)             \
+        IIO_DEVICE_ATTR(cap_gain, _mode, _show, _store, 0)
+#define IIO_DEV_ATTR_CAP_DATA(_show)            \
+        IIO_DEVICE_ATTR(cap0_raw, S_IRUGO, _show, NULL, 0)
+#define IIO_DEV_ATTR_VT_DATA(_show)             \
+        IIO_DEVICE_ATTR(in0_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(capdac0_raw, S_IRUGO | S_IWUSR,
+                        ad774x_show_dac_value,
+                        ad774x_store_dac_value,
+                        AD774X_CAPDACA);
+
+static IIO_DEVICE_ATTR(capdac1_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_cap_setup.dev_attr.attr,
+        &iio_dev_attr_in0_setup.dev_attr.attr,
+        &iio_dev_attr_exec_setup.dev_attr.attr,
+        &iio_dev_attr_cap_offs.dev_attr.attr,
+        &iio_dev_attr_cap_gain.dev_attr.attr,
+        &iio_dev_attr_in0_gain.dev_attr.attr,
+        &iio_dev_attr_in0_raw.dev_attr.attr,
+        &iio_dev_attr_cap0_raw.dev_attr.attr,
+        &iio_dev_attr_capdac0_raw.dev_attr.attr,
+        &iio_dev_attr_capdac1_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, 0,
+                               IIO_EVENT_CODE_CAP_RDY,
+                               iio_get_time_ns());
+
+        if (int_status & AD774X_STATUS_RDYVT)
+                iio_push_event(indio_dev, 0,
+                               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,
+};
+
+static const struct iio_info ad774x_info = {
+        .attrs = &ad774x_event_attribute_group,
+        .event_attrs = &ad774x_event_attribute_group,
+        .num_interrupt_lines = 1,
+        .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 = 0, regdone = 0;
+        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;
+
+        ret = iio_device_register(indio_dev);
+        if (ret)
+                goto error_free_dev;
+        regdone = 1;
+
+        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;
+        }
+
+        dev_err(&client->dev, "%s capacitive sensor registered, irq: %d\n", id->name, client->irq);
+
+        return 0;
+
+error_free_dev:
+        if (regdone)
+                free_irq(client->irq, indio_dev);
+        else
+                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);