Staging: iio: add digital compass hmc5843 driver (b4e17822) · Commits · e / devices / android_kernel_xiaomi_markw

drivers/staging/iio/Kconfig

+1 −0

Original line number	Diff line number	Diff line
		@@ -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"

drivers/staging/iio/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -15,3 +15,4 @@ obj-y += gyro/
		obj-y += imu/
		obj-y += light/
		obj-y += trigger/
		obj-y += magnetometer/

drivers/staging/iio/magnetometer/Kconfig

0 → 100644

+15 −0

Original line number	Diff line number	Diff line
		#
		# 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

drivers/staging/iio/magnetometer/Makefile

0 → 100644

+5 −0

Original line number	Diff line number	Diff line
		#
		# Makefile for industrial I/O Magnetometer sensors
		#

		obj-$(CONFIG_SENSORS_HMC5843) += hmc5843.o

drivers/staging/iio/magnetometer/hmc5843.c

0 → 100644

+624 −0

Original line number	Diff line number	Diff line
		/* 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);