diff options
Diffstat (limited to 'drivers/staging/iio/adc/ad7745.c')
| -rw-r--r-- | drivers/staging/iio/adc/ad7745.c | 734 |
1 files changed, 734 insertions, 0 deletions
diff --git a/drivers/staging/iio/adc/ad7745.c b/drivers/staging/iio/adc/ad7745.c new file mode 100644 index 000000000000..ab7ef8450ae2 --- /dev/null +++ b/drivers/staging/iio/adc/ad7745.c @@ -0,0 +1,734 @@ +/* + * 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/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" + +/* + * 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 { + const char *name; + struct i2c_client *client; + struct iio_dev *indio_dev; + struct work_struct thresh_work; + bool inter; + s64 last_timestamp; + 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; +}; + +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(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 = dev_info->dev_data; + + 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 = dev_info->dev_data; + 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 = dev_info->dev_data; + 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 = dev_info->dev_data; + 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 = dev_info->dev_data; + + 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 = dev_info->dev_data; + 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 = dev_info->dev_data; + + 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 = dev_info->dev_data; + 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 = dev_info->dev_data; + + 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 = dev_info->dev_data; + 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 = dev_info->dev_data; + + 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 = dev_info->dev_data; + 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 = dev_info->dev_data; + 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 = dev_info->dev_data; + 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 = dev_info->dev_data; + + 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 = dev_info->dev_data; + 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 = dev_info->dev_data; + + 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 = dev_info->dev_data; + 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 ssize_t ad774x_show_name(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *dev_info = dev_get_drvdata(dev); + struct ad774x_chip_info *chip = dev_info->dev_data; + return sprintf(buf, "%s\n", chip->name); +} + +static IIO_DEVICE_ATTR(name, S_IRUGO, ad774x_show_name, NULL, 0); + +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, + &iio_dev_attr_name.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ad774x_attribute_group = { + .attrs = ad774x_attributes, +}; + +/* + * data ready events + */ + +#define IIO_EVENT_CODE_CAP_RDY IIO_BUFFER_EVENT_CODE(0) +#define IIO_EVENT_CODE_VT_RDY IIO_BUFFER_EVENT_CODE(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 void ad774x_interrupt_handler_bh(struct work_struct *work_s) +{ + struct ad774x_chip_info *chip = + container_of(work_s, struct ad774x_chip_info, thresh_work); + u8 int_status; + + enable_irq(chip->client->irq); + + ad774x_i2c_read(chip, AD774X_STATUS, &int_status, 1); + + if (int_status & AD774X_STATUS_RDYCAP) + iio_push_event(chip->indio_dev, 0, + IIO_EVENT_CODE_CAP_RDY, + chip->last_timestamp); + + if (int_status & AD774X_STATUS_RDYVT) + iio_push_event(chip->indio_dev, 0, + IIO_EVENT_CODE_VT_RDY, + chip->last_timestamp); +} + +static int ad774x_interrupt_handler_th(struct iio_dev *dev_info, + int index, + s64 timestamp, + int no_test) +{ + struct ad774x_chip_info *chip = dev_info->dev_data; + + chip->last_timestamp = timestamp; + schedule_work(&chip->thresh_work); + + return 0; +} + +IIO_EVENT_SH(data_rdy, &ad774x_interrupt_handler_th); + +static ssize_t ad774x_query_out_mode(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + /* + * AD774X provides one /RDY pin, which can be used as interrupt + * but the pin is not configurable + */ + return sprintf(buf, "1\n"); +} + +static ssize_t ad774x_set_out_mode(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + return len; +} + +IIO_EVENT_ATTR_CAP_RDY_SH(iio_event_data_rdy, ad774x_query_out_mode, ad774x_set_out_mode, 0); +IIO_EVENT_ATTR_VT_RDY_SH(iio_event_data_rdy, ad774x_query_out_mode, ad774x_set_out_mode, 0); + +static struct attribute *ad774x_event_attributes[] = { + &iio_event_attr_cap_rdy.dev_attr.attr, + &iio_event_attr_vt_rdy.dev_attr.attr, + NULL, +}; + +static struct attribute_group ad774x_event_attribute_group = { + .attrs = ad774x_event_attributes, +}; + +/* + * 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 = 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; + } + + /* Establish that the iio_dev is a child of the i2c device */ + chip->indio_dev->dev.parent = &client->dev; + chip->indio_dev->attrs = &ad774x_attribute_group; + chip->indio_dev->event_attrs = &ad774x_event_attribute_group; + chip->indio_dev->dev_data = (void *)(chip); + chip->indio_dev->driver_module = THIS_MODULE; + chip->indio_dev->num_interrupt_lines = 1; + chip->indio_dev->modes = INDIO_DIRECT_MODE; + + ret = iio_device_register(chip->indio_dev); + if (ret) + goto error_free_dev; + regdone = 1; + + if (client->irq) { + ret = iio_register_interrupt_line(client->irq, + chip->indio_dev, + 0, + IRQF_TRIGGER_FALLING, + "ad774x"); + if (ret) + goto error_free_dev; + + iio_add_event_to_list(iio_event_attr_cap_rdy.listel, + &chip->indio_dev->interrupts[0]->ev_list); + + INIT_WORK(&chip->thresh_work, ad774x_interrupt_handler_bh); + } + + dev_err(&client->dev, "%s capacitive sensor registered, irq: %d\n", id->name, client->irq); + + return 0; + +error_free_dev: + if (regdone) + iio_device_unregister(chip->indio_dev); + else + iio_free_device(chip->indio_dev); +error_free_chip: + kfree(chip); +error_ret: + return ret; +} + +static int __devexit ad774x_remove(struct i2c_client *client) +{ + struct ad774x_chip_info *chip = i2c_get_clientdata(client); + struct iio_dev *indio_dev = chip->indio_dev; + + if (client->irq) + iio_unregister_interrupt_line(indio_dev, 0); + iio_device_unregister(indio_dev); + kfree(chip); + + 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); |