diff options
author | Shubhrajyoti D <shubhrajyoti@ti.com> | 2010-07-17 13:02:52 (GMT) |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-07-22 21:26:57 (GMT) |
commit | b4e178224cfdc8aae7dda0baab34a4e4110a2e93 (patch) | |
tree | 29f3e3da22b4af2e9276056b1fff4d20c1d34391 /drivers | |
parent | 5fc9e4d527f059a996f4725a596698fa76c0370f (diff) | |
download | linux-fsl-qoriq-b4e178224cfdc8aae7dda0baab34a4e4110a2e93.tar.xz |
Staging: iio: add digital compass hmc5843 driver
Adding support for the Honeywell HMC5843. The interface to the device is
i2c
TODO:
Adding the documentation
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/staging/iio/Kconfig | 1 | ||||
-rw-r--r-- | drivers/staging/iio/Makefile | 1 | ||||
-rw-r--r-- | drivers/staging/iio/magnetometer/Kconfig | 15 | ||||
-rw-r--r-- | drivers/staging/iio/magnetometer/Makefile | 5 | ||||
-rw-r--r-- | drivers/staging/iio/magnetometer/hmc5843.c | 624 |
5 files changed, 646 insertions, 0 deletions
diff --git a/drivers/staging/iio/Kconfig b/drivers/staging/iio/Kconfig index b0e6244..569b938 100644 --- a/drivers/staging/iio/Kconfig +++ b/drivers/staging/iio/Kconfig @@ -44,6 +44,7 @@ source "drivers/staging/iio/adc/Kconfig" source "drivers/staging/iio/gyro/Kconfig" source "drivers/staging/iio/imu/Kconfig" source "drivers/staging/iio/light/Kconfig" +source "drivers/staging/iio/magnetometer/Kconfig" source "drivers/staging/iio/trigger/Kconfig" diff --git a/drivers/staging/iio/Makefile b/drivers/staging/iio/Makefile index fff717e..e909674 100644 --- a/drivers/staging/iio/Makefile +++ b/drivers/staging/iio/Makefile @@ -15,3 +15,4 @@ obj-y += gyro/ obj-y += imu/ obj-y += light/ obj-y += trigger/ +obj-y += magnetometer/ diff --git a/drivers/staging/iio/magnetometer/Kconfig b/drivers/staging/iio/magnetometer/Kconfig new file mode 100644 index 0000000..d014450 --- /dev/null +++ b/drivers/staging/iio/magnetometer/Kconfig @@ -0,0 +1,15 @@ +# +# Magnetometer sensors +# +comment "Magnetometer sensors" + +config SENSORS_HMC5843 + tristate "Honeywell HMC5843 3-Axis Magnetometer" + depends on I2C + help + Say Y here to add support for the Honeywell HMC 5843 3-Axis + Magnetometer (digital compass). + + To compile this driver as a module, choose M here: the module + will be called hmc5843 + diff --git a/drivers/staging/iio/magnetometer/Makefile b/drivers/staging/iio/magnetometer/Makefile new file mode 100644 index 0000000..f9bfb2e --- /dev/null +++ b/drivers/staging/iio/magnetometer/Makefile @@ -0,0 +1,5 @@ +# +# Makefile for industrial I/O Magnetometer sensors +# + +obj-$(CONFIG_SENSORS_HMC5843) += hmc5843.o diff --git a/drivers/staging/iio/magnetometer/hmc5843.c b/drivers/staging/iio/magnetometer/hmc5843.c new file mode 100644 index 0000000..92f6c6f --- /dev/null +++ b/drivers/staging/iio/magnetometer/hmc5843.c @@ -0,0 +1,624 @@ +/* Copyright (C) 2010 Texas Instruments + Author: Shubhrajyoti Datta <shubhrajyoti@ti.com> + Acknowledgement: Jonathan Cameron <jic23@cam.ac.uk> for valuable inputs. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +*/ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/slab.h> +#include <linux/types.h> +#include "../iio.h" +#include "../sysfs.h" +#include "magnet.h" + +#define HMC5843_I2C_ADDRESS 0x1E + +#define HMC5843_CONFIG_REG_A 0x00 +#define HMC5843_CONFIG_REG_B 0x01 +#define HMC5843_MODE_REG 0x02 +#define HMC5843_DATA_OUT_X_MSB_REG 0x03 +#define HMC5843_DATA_OUT_X_LSB_REG 0x04 +#define HMC5843_DATA_OUT_Y_MSB_REG 0x05 +#define HMC5843_DATA_OUT_Y_LSB_REG 0x06 +#define HMC5843_DATA_OUT_Z_MSB_REG 0x07 +#define HMC5843_DATA_OUT_Z_LSB_REG 0x08 +#define HMC5843_STATUS_REG 0x09 +#define HMC5843_ID_REG_A 0x0A +#define HMC5843_ID_REG_B 0x0B +#define HMC5843_ID_REG_C 0x0C + +#define HMC5843_ID_REG_LENGTH 0x03 +#define HMC5843_ID_STRING "H43" + +/* + * Range settings in (+-)Ga + * */ +#define RANGE_GAIN_OFFSET 0x05 + +#define RANGE_0_7 0x00 +#define RANGE_1_0 0x01 /* default */ +#define RANGE_1_5 0x02 +#define RANGE_2_0 0x03 +#define RANGE_3_2 0x04 +#define RANGE_3_8 0x05 +#define RANGE_4_5 0x06 +#define RANGE_6_5 0x07 /* Not recommended */ + +/* + * Device status + */ +#define DATA_READY 0x01 +#define DATA_OUTPUT_LOCK 0x02 +#define VOLTAGE_REGULATOR_ENABLED 0x04 + +/* + * Mode register configuration + */ +#define MODE_CONVERSION_CONTINUOUS 0x00 +#define MODE_CONVERSION_SINGLE 0x01 +#define MODE_IDLE 0x02 +#define MODE_SLEEP 0x03 + +/* Minimum Data Output Rate in 1/10 Hz */ +#define RATE_OFFSET 0x02 +#define RATE_BITMASK 0x1C +#define RATE_5 0x00 +#define RATE_10 0x01 +#define RATE_20 0x02 +#define RATE_50 0x03 +#define RATE_100 0x04 +#define RATE_200 0x05 +#define RATE_500 0x06 +#define RATE_NOT_USED 0x07 + +/* + * Device Configutration + */ +#define CONF_NORMAL 0x00 +#define CONF_POSITIVE_BIAS 0x01 +#define CONF_NEGATIVE_BIAS 0x02 +#define CONF_NOT_USED 0x03 +#define MEAS_CONF_MASK 0x03 + +static const int regval_to_counts_per_mg[] = { + 1620, + 1300, + 970, + 780, + 530, + 460, + 390, + 280 +}; +static const int regval_to_input_field_mg[] = { + 700, + 1000, + 1500, + 2000, + 3200, + 3800, + 4500, + 6500 +}; +static const char *regval_to_samp_freq[] = { + "0.5", + "1", + "2", + "5", + "10", + "20", + "50", +}; + +/* Addresses to scan: 0x1E */ +static const unsigned short normal_i2c[] = { HMC5843_I2C_ADDRESS, + I2C_CLIENT_END }; + +/* Each client has this additional data */ +struct hmc5843_data { + struct iio_dev *indio_dev; + struct mutex lock; + u8 rate; + u8 meas_conf; + u8 operating_mode; + u8 range; +}; + +static void hmc5843_init_client(struct i2c_client *client); + +static s32 hmc5843_configure(struct i2c_client *client, + u8 operating_mode) +{ + /* The lower two bits contain the current conversion mode */ + return i2c_smbus_write_byte_data(client, + HMC5843_MODE_REG, + (operating_mode & 0x03)); +} + +/* Return the measurement value from the specified channel */ +static ssize_t hmc5843_read_measurement(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct i2c_client *client = to_i2c_client(indio_dev->dev.parent); + s16 coordinate_val; + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + struct hmc5843_data *data = indio_dev->dev_data; + s32 result; + + mutex_lock(&data->lock); + + result = i2c_smbus_read_byte_data(client, HMC5843_STATUS_REG); + while (!(result & DATA_READY)) + result = i2c_smbus_read_byte_data(client, HMC5843_STATUS_REG); + + result = i2c_smbus_read_word_data(client, this_attr->address); + mutex_unlock(&data->lock); + if (result < 0) + return -EINVAL; + + coordinate_val = (s16)swab16((u16)result); + return sprintf(buf, "%d\n", coordinate_val); +} +static IIO_DEV_ATTR_MAGN_X(hmc5843_read_measurement, + HMC5843_DATA_OUT_X_MSB_REG); +static IIO_DEV_ATTR_MAGN_Y(hmc5843_read_measurement, + HMC5843_DATA_OUT_Y_MSB_REG); +static IIO_DEV_ATTR_MAGN_Z(hmc5843_read_measurement, + HMC5843_DATA_OUT_Z_MSB_REG); + +/* + * From the datasheet + * 0 - Continuous-Conversion Mode: In continuous-conversion mode, the + * device continuously performs conversions an places the result in the + * data register. + * + * 1 - Single-Conversion Mode : device performs a single measurement, + * sets RDY high and returned to sleep mode + * + * 2 - Idle Mode : Device is placed in idle mode. + * + * 3 - Sleep Mode. Device is placed in sleep mode. + * + */ +static ssize_t hmc5843_show_operating_mode(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct hmc5843_data *data = indio_dev->dev_data; + return sprintf(buf, "%d\n", data->operating_mode); +} + +static ssize_t hmc5843_set_operating_mode(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct i2c_client *client = to_i2c_client(indio_dev->dev.parent); + struct hmc5843_data *data = indio_dev->dev_data; + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + unsigned long operating_mode = 0; + s32 status; + int error; + mutex_lock(&data->lock); + error = strict_strtoul(buf, 10, &operating_mode); + if (error) + return error; + dev_dbg(dev, "set Conversion mode to %lu\n", operating_mode); + if (operating_mode > MODE_SLEEP) + return -EINVAL; + + status = i2c_smbus_write_byte_data(client, this_attr->address, + operating_mode); + if (status) { + count = -EINVAL; + goto exit; + } + data->operating_mode = operating_mode; + +exit: + mutex_unlock(&data->lock); + return count; +} +static IIO_DEVICE_ATTR(operating_mode, + S_IWUSR | S_IRUGO, + hmc5843_show_operating_mode, + hmc5843_set_operating_mode, + HMC5843_MODE_REG); + +/* + * API for setting the measurement configuration to + * Normal, Positive bias and Negative bias + * From the datasheet + * + * Normal measurement configuration (default): In normal measurement + * configuration the device follows normal measurement flow. Pins BP and BN + * are left floating and high impedance. + * + * Positive bias configuration: In positive bias configuration, a positive + * current is forced across the resistive load on pins BP and BN. + * + * Negative bias configuration. In negative bias configuration, a negative + * current is forced across the resistive load on pins BP and BN. + * + */ +static s32 hmc5843_set_meas_conf(struct i2c_client *client, + u8 meas_conf) +{ + struct hmc5843_data *data = i2c_get_clientdata(client); + u8 reg_val; + reg_val = (meas_conf & MEAS_CONF_MASK) | (data->rate << RATE_OFFSET); + return i2c_smbus_write_byte_data(client, HMC5843_CONFIG_REG_A, reg_val); +} + +static ssize_t hmc5843_show_measurement_configuration(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct hmc5843_data *data = indio_dev->dev_data; + return sprintf(buf, "%d\n", data->meas_conf); +} + +static ssize_t hmc5843_set_measurement_configuration(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct i2c_client *client = to_i2c_client(indio_dev->dev.parent); + struct hmc5843_data *data = i2c_get_clientdata(client); + unsigned long meas_conf = 0; + int error = strict_strtoul(buf, 10, &meas_conf); + if (error) + return error; + mutex_lock(&data->lock); + + dev_dbg(dev, "set mode to %lu\n", meas_conf); + if (hmc5843_set_meas_conf(client, meas_conf)) { + count = -EINVAL; + goto exit; + } + data->meas_conf = meas_conf; + +exit: + mutex_unlock(&data->lock); + return count; +} +static IIO_DEVICE_ATTR(meas_conf, + S_IWUSR | S_IRUGO, + hmc5843_show_measurement_configuration, + hmc5843_set_measurement_configuration, + 0); + +/* + * From Datasheet + * The table shows the minimum data output + * Value | Minimum data output rate(Hz) + * 0 | 0.5 + * 1 | 1 + * 2 | 2 + * 3 | 5 + * 4 | 10 (default) + * 5 | 20 + * 6 | 50 + * 7 | Not used + */ +static IIO_CONST_ATTR_AVAIL_SAMP_FREQ("0.5 1 2 5 10 20 50"); + +static s32 hmc5843_set_rate(struct i2c_client *client, + u8 rate) +{ + struct hmc5843_data *data = i2c_get_clientdata(client); + u8 reg_val; + + reg_val = (data->meas_conf) | (rate << RATE_OFFSET); + if (rate >= RATE_NOT_USED) { + dev_err(&client->dev, + "This data output rate is not supported \n"); + return -EINVAL; + } + return i2c_smbus_write_byte_data(client, HMC5843_CONFIG_REG_A, reg_val); +} + +static ssize_t set_sampling_frequency(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct i2c_client *client = to_i2c_client(indio_dev->dev.parent); + struct hmc5843_data *data = indio_dev->dev_data; + unsigned long rate = 0; + + if (strncmp(buf, "0.5" , 3) == 0) + rate = RATE_5; + else if (strncmp(buf, "1" , 1) == 0) + rate = RATE_10; + else if (strncmp(buf, "2", 1) == 0) + rate = RATE_20; + else if (strncmp(buf, "5", 1) == 0) + rate = RATE_50; + else if (strncmp(buf, "10", 2) == 0) + rate = RATE_100; + else if (strncmp(buf, "20" , 2) == 0) + rate = RATE_200; + else if (strncmp(buf, "50" , 2) == 0) + rate = RATE_500; + else + return -EINVAL; + + mutex_lock(&data->lock); + dev_dbg(dev, "set rate to %lu\n", rate); + if (hmc5843_set_rate(client, rate)) { + count = -EINVAL; + goto exit; + } + data->rate = rate; + +exit: + mutex_unlock(&data->lock); + return count; +} + +static ssize_t show_sampling_frequency(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct i2c_client *client = to_i2c_client(indio_dev->dev.parent); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + u32 rate; + + rate = i2c_smbus_read_byte_data(client, this_attr->address); + if (rate < 0) + return -EINVAL; + rate = (rate & RATE_BITMASK) >> RATE_OFFSET; + return sprintf(buf, "%s\n", regval_to_samp_freq[rate]); +} +static IIO_DEVICE_ATTR(sampling_frequency, + S_IWUSR | S_IRUGO, + show_sampling_frequency, + set_sampling_frequency, + HMC5843_CONFIG_REG_A); + +/* + * From Datasheet + * Nominal gain settings + * Value | Sensor Input Field Range(Ga) | Gain(counts/ milli-gauss) + *0 |(+-)0.7 |1620 + *1 |(+-)1.0 |1300 + *2 |(+-)1.5 |970 + *3 |(+-)2.0 |780 + *4 |(+-)3.2 |530 + *5 |(+-)3.8 |460 + *6 |(+-)4.5 |390 + *7 |(+-)6.5 |280 + */ +static ssize_t show_range(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + u8 range; + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct hmc5843_data *data = indio_dev->dev_data; + + range = data->range; + return sprintf(buf, "%d\n", regval_to_input_field_mg[range]); +} + +static ssize_t set_range(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct i2c_client *client = to_i2c_client(indio_dev->dev.parent); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + struct hmc5843_data *data = indio_dev->dev_data; + unsigned long range = 0; + int error; + mutex_lock(&data->lock); + error = strict_strtoul(buf, 10, &range); + if (error) + return error; + dev_dbg(dev, "set range to %lu\n", range); + + if (range > RANGE_6_5) + return -EINVAL; + + data->range = range; + range = range << RANGE_GAIN_OFFSET; + if (i2c_smbus_write_byte_data(client, this_attr->address, range)) + count = -EINVAL; + + mutex_unlock(&data->lock); + return count; + +} +static IIO_DEVICE_ATTR(magn_range, + S_IWUSR | S_IRUGO, + show_range, + set_range, + HMC5843_CONFIG_REG_B); + +static ssize_t show_gain(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct hmc5843_data *data = indio_dev->dev_data; + return sprintf(buf, "%d\n", regval_to_counts_per_mg[data->range]); +} +static IIO_DEVICE_ATTR(magn_gain, + S_IRUGO, + show_gain, + NULL , 0); + +static struct attribute *hmc5843_attributes[] = { + &iio_dev_attr_meas_conf.dev_attr.attr, + &iio_dev_attr_operating_mode.dev_attr.attr, + &iio_dev_attr_sampling_frequency.dev_attr.attr, + &iio_dev_attr_magn_range.dev_attr.attr, + &iio_dev_attr_magn_gain.dev_attr.attr, + &iio_dev_attr_magn_x_raw.dev_attr.attr, + &iio_dev_attr_magn_y_raw.dev_attr.attr, + &iio_dev_attr_magn_z_raw.dev_attr.attr, + &iio_const_attr_available_sampling_frequency.dev_attr.attr, + NULL +}; + +static const struct attribute_group hmc5843_group = { + .attrs = hmc5843_attributes, +}; + +static int hmc5843_detect(struct i2c_client *client, + struct i2c_board_info *info) +{ + unsigned char id_str[HMC5843_ID_REG_LENGTH]; + + if (client->addr != HMC5843_I2C_ADDRESS) + return -ENODEV; + + if (i2c_smbus_read_i2c_block_data(client, HMC5843_ID_REG_A, + HMC5843_ID_REG_LENGTH, id_str) + != HMC5843_ID_REG_LENGTH) + return -ENODEV; + + if (0 != strncmp(id_str, HMC5843_ID_STRING, HMC5843_ID_REG_LENGTH)) + return -ENODEV; + + return 0; +} + +/* Called when we have found a new HMC5843. */ +static void hmc5843_init_client(struct i2c_client *client) +{ + struct hmc5843_data *data = i2c_get_clientdata(client); + hmc5843_set_meas_conf(client, data->meas_conf); + hmc5843_set_rate(client, data->rate); + hmc5843_configure(client, data->operating_mode); + i2c_smbus_write_byte_data(client, HMC5843_CONFIG_REG_B, data->range); + mutex_init(&data->lock); + pr_info("HMC5843 initialized\n"); +} + +static int hmc5843_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct hmc5843_data *data; + int err = 0; + + data = kzalloc(sizeof(struct hmc5843_data), GFP_KERNEL); + if (!data) { + err = -ENOMEM; + goto exit; + } + + /* default settings at probe */ + + data->meas_conf = CONF_NORMAL; + data->range = RANGE_1_0; + data->operating_mode = MODE_CONVERSION_CONTINUOUS; + + i2c_set_clientdata(client, data); + + /* Initialize the HMC5843 chip */ + hmc5843_init_client(client); + + data->indio_dev = iio_allocate_device(); + if (!data->indio_dev) { + err = -ENOMEM; + goto exit_free1; + } + data->indio_dev->attrs = &hmc5843_group; + data->indio_dev->dev.parent = &client->dev; + data->indio_dev->dev_data = (void *)(data); + data->indio_dev->driver_module = THIS_MODULE; + data->indio_dev->modes = INDIO_DIRECT_MODE; + err = iio_device_register(data->indio_dev); + if (err) + goto exit_free2; + return 0; +exit_free2: + iio_free_device(data->indio_dev); +exit_free1: + kfree(data); +exit: + return err; +} + +static int hmc5843_remove(struct i2c_client *client) +{ + struct hmc5843_data *data = i2c_get_clientdata(client); + /* sleep mode to save power */ + hmc5843_configure(client, MODE_SLEEP); + iio_device_unregister(data->indio_dev); + kfree(i2c_get_clientdata(client)); + return 0; +} + +static int hmc5843_suspend(struct i2c_client *client, pm_message_t mesg) +{ + hmc5843_configure(client, MODE_SLEEP); + return 0; +} + +static int hmc5843_resume(struct i2c_client *client) +{ + struct hmc5843_data *data = i2c_get_clientdata(client); + hmc5843_configure(client, data->operating_mode); + return 0; +} + +static const struct i2c_device_id hmc5843_id[] = { + { "hmc5843", 0 }, + { } +}; + +static struct i2c_driver hmc5843_driver = { + .driver = { + .name = "hmc5843", + }, + .id_table = hmc5843_id, + .probe = hmc5843_probe, + .remove = hmc5843_remove, + .detect = hmc5843_detect, + .address_list = normal_i2c, + .suspend = hmc5843_suspend, + .resume = hmc5843_resume, +}; + +static int __init hmc5843_init(void) +{ + return i2c_add_driver(&hmc5843_driver); +} + +static void __exit hmc5843_exit(void) +{ + i2c_del_driver(&hmc5843_driver); +} + +MODULE_AUTHOR("Shubhrajyoti Datta <shubhrajyoti@ti.com"); +MODULE_DESCRIPTION("HMC5843 driver"); +MODULE_LICENSE("GPL"); + +module_init(hmc5843_init); +module_exit(hmc5843_exit); |