misc: clean up bmp085 driver (e939ca0a) · Commits · e / devices / android_kernel_samsung_universal8895

drivers/misc/bmp085.c

+103 −103

Original line number	Original line	Diff line number	Diff line
	/* Copyright (c) 2010 Christoph Mair <christoph.mair@gmail.com>		/* Copyright (c) 2010 Christoph Mair <christoph.mair@gmail.com>
			* Copyright (c) 2012 Bosch Sensortec GmbH
	This driver supports the bmp085 digital barometric pressure		* Copyright (c) 2012 Unixphere AB
	and temperature sensor from Bosch Sensortec. The datasheet		*
	is available from their website:		* This driver supports the bmp085 digital barometric pressure
	http://www.bosch-sensortec.com/content/language1/downloads/BST-BMP085-DS000-05.pdf		* and temperature sensor from Bosch Sensortec. The datasheet
			* is available from their website:
	A pressure measurement is issued by reading from pressure0_input.		* http://www.bosch-sensortec.com/content/language1/downloads/BST-BMP085-DS000-05.pdf
	The return value ranges from 30000 to 110000 pascal with a resulution		*
	of 1 pascal (0.01 millibar) which enables measurements from 9000m above		* A pressure measurement is issued by reading from pressure0_input.
	to 500m below sea level.		* The return value ranges from 30000 to 110000 pascal with a resulution
			* of 1 pascal (0.01 millibar) which enables measurements from 9000m above
	The temperature can be read from temp0_input. Values range from		* to 500m below sea level.
	-400 to 850 representing the ambient temperature in degree celsius		*
	multiplied by 10.The resolution is 0.1 celsius.		* The temperature can be read from temp0_input. Values range from
			* -400 to 850 representing the ambient temperature in degree celsius
	Because ambient pressure is temperature dependent, a temperature		* multiplied by 10.The resolution is 0.1 celsius.
	measurement will be executed automatically even if the user is reading		*
	from pressure0_input. This happens if the last temperature measurement		* Because ambient pressure is temperature dependent, a temperature
	has been executed more then one second ago.		* measurement will be executed automatically even if the user is reading
			* from pressure0_input. This happens if the last temperature measurement
	To decrease RMS noise from pressure measurements, the bmp085 can		* has been executed more then one second ago.
	autonomously calculate the average of up to eight samples. This is		*
	set up by writing to the oversampling sysfs file. Accepted values		* To decrease RMS noise from pressure measurements, the bmp085 can
	are 0, 1, 2 and 3. 2^x when x is the value written to this file		* autonomously calculate the average of up to eight samples. This is
	specifies the number of samples used to calculate the ambient pressure.		* set up by writing to the oversampling sysfs file. Accepted values
	RMS noise is specified with six pascal (without averaging) and decreases		* are 0, 1, 2 and 3. 2^x when x is the value written to this file
	down to 3 pascal when using an oversampling setting of 3.		* specifies the number of samples used to calculate the ambient pressure.
			* RMS noise is specified with six pascal (without averaging) and decreases
	This program is free software; you can redistribute it and/or modify		* down to 3 pascal when using an oversampling setting of 3.
	it under the terms of the GNU General Public License as published by		*
	the Free Software Foundation; either version 2 of the License, or		* This program is free software; you can redistribute it and/or modify
	(at your option) any later version.		* it under the terms of the GNU General Public License as published by
			* the Free Software Foundation; either version 2 of the License, or
	This program is distributed in the hope that it will be useful,		* (at your option) any later version.
	but WITHOUT ANY WARRANTY; without even the implied warranty of		*
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the		* This program is distributed in the hope that it will be useful,
	GNU General Public License for more details.		* but WITHOUT ANY WARRANTY; without even the implied warranty of
			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	You should have received a copy of the GNU General Public License		* GNU General Public License for more details.
	along with this program; if not, write to the Free Software		*
	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.		* 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/module.h>
			#include <linux/device.h>
	#include <linux/init.h>		#include <linux/init.h>
	#include <linux/i2c.h>		#include <linux/i2c.h>
	#include <linux/slab.h>		#include <linux/slab.h>
	#include <linux/delay.h>		#include <linux/delay.h>

			#define BMP085_NAME "bmp085"
	#define BMP085_I2C_ADDRESS 0x77		#define BMP085_I2C_ADDRESS 0x77
	#define BMP085_CHIP_ID 0x55		#define BMP085_CHIP_ID 0x55

	#define BMP085_CALIBRATION_DATA_START 0xAA		#define BMP085_CALIBRATION_DATA_START 0xAA
	#define BMP085_CALIBRATION_DATA_LENGTH 11 /* 16 bit values */		#define BMP085_CALIBRATION_DATA_LENGTH 11 /* 16 bit values */
	#define BMP085_CHIP_ID_REG 0xD0		#define BMP085_CHIP_ID_REG 0xD0
	#define BMP085_VERSION_REG 0xD1
	#define BMP085_CTRL_REG 0xF4		#define BMP085_CTRL_REG 0xF4
	#define BMP085_TEMP_MEASUREMENT 0x2E		#define BMP085_TEMP_MEASUREMENT 0x2E
	#define BMP085_PRESSURE_MEASUREMENT 0x34		#define BMP085_PRESSURE_MEASUREMENT 0x34
	@@ -65,9 +66,6 @@
	#define BMP085_CONVERSION_REGISTER_XLSB 0xF8		#define BMP085_CONVERSION_REGISTER_XLSB 0xF8
	#define BMP085_TEMP_CONVERSION_TIME 5		#define BMP085_TEMP_CONVERSION_TIME 5

	#define BMP085_CLIENT_NAME "bmp085"


	static const unsigned short normal_i2c[] = { BMP085_I2C_ADDRESS,		static const unsigned short normal_i2c[] = { BMP085_I2C_ADDRESS,
	I2C_CLIENT_END };		I2C_CLIENT_END };

	@@ -78,20 +76,18 @@ struct bmp085_calibration_data {
	s16 MB, MC, MD;		s16 MB, MC, MD;
	};		};


	/* Each client has this additional data */
	struct bmp085_data {		struct bmp085_data {
	struct i2c_client *client;		struct i2c_client *client;
	struct mutex lock;		struct mutex lock;
	struct bmp085_calibration_data calibration;		struct bmp085_calibration_data calibration;
			u8 oversampling_setting;
	u32 raw_temperature;		u32 raw_temperature;
	u32 raw_pressure;		u32 raw_pressure;
	unsigned char oversampling_setting;		u32 temp_measurement_period;
	unsigned long last_temp_measurement;		unsigned long last_temp_measurement;
	s32 b6; /* calculated temperature correction coefficient */		s32 b6; /* calculated temperature correction coefficient */
	};		};


	static s32 bmp085_read_calibration_data(struct i2c_client *client)		static s32 bmp085_read_calibration_data(struct i2c_client *client)
	{		{
	u16 tmp[BMP085_CALIBRATION_DATA_LENGTH];		u16 tmp[BMP085_CALIBRATION_DATA_LENGTH];
	@@ -99,12 +95,12 @@ static s32 bmp085_read_calibration_data(struct i2c_client *client)
	struct bmp085_calibration_data *cali = &(data->calibration);		struct bmp085_calibration_data *cali = &(data->calibration);
	s32 status = i2c_smbus_read_i2c_block_data(client,		s32 status = i2c_smbus_read_i2c_block_data(client,
	BMP085_CALIBRATION_DATA_START,		BMP085_CALIBRATION_DATA_START,
	BMP085_CALIBRATION_DATA_LENGTH*sizeof(u16),		(BMP085_CALIBRATION_DATA_LENGTH << 1),
	(u8 *)tmp);		(u8 *)tmp);
	if (status < 0)		if (status < 0)
	return status;		return status;

	if (status != BMP085_CALIBRATION_DATA_LENGTH*sizeof(u16))		if (status != (BMP085_CALIBRATION_DATA_LENGTH << 1))
	return -EIO;		return -EIO;

	cali->AC1 = be16_to_cpu(tmp[0]);		cali->AC1 = be16_to_cpu(tmp[0]);
	@@ -121,7 +117,6 @@ static s32 bmp085_read_calibration_data(struct i2c_client *client)
	return 0;		return 0;
	}		}


	static s32 bmp085_update_raw_temperature(struct bmp085_data *data)		static s32 bmp085_update_raw_temperature(struct bmp085_data *data)
	{		{
	u16 tmp;		u16 tmp;
	@@ -130,7 +125,7 @@ static s32 bmp085_update_raw_temperature(struct bmp085_data *data)
	mutex_lock(&data->lock);		mutex_lock(&data->lock);
	status = i2c_smbus_write_byte_data(data->client, BMP085_CTRL_REG,		status = i2c_smbus_write_byte_data(data->client, BMP085_CTRL_REG,
	BMP085_TEMP_MEASUREMENT);		BMP085_TEMP_MEASUREMENT);
	if (status != 0) {		if (status < 0) {
	dev_err(&data->client->dev,		dev_err(&data->client->dev,
	"Error while requesting temperature measurement.\n");		"Error while requesting temperature measurement.\n");
	goto exit;		goto exit;
	@@ -163,8 +158,9 @@ static s32 bmp085_update_raw_pressure(struct bmp085_data *data)

	mutex_lock(&data->lock);		mutex_lock(&data->lock);
	status = i2c_smbus_write_byte_data(data->client, BMP085_CTRL_REG,		status = i2c_smbus_write_byte_data(data->client, BMP085_CTRL_REG,
	BMP085_PRESSURE_MEASUREMENT + (data->oversampling_setting<<6));		BMP085_PRESSURE_MEASUREMENT +
	if (status != 0) {		(data->oversampling_setting << 6));
			if (status < 0) {
	dev_err(&data->client->dev,		dev_err(&data->client->dev,
	"Error while requesting pressure measurement.\n");		"Error while requesting pressure measurement.\n");
	goto exit;		goto exit;
	@@ -193,7 +189,6 @@ exit:
	return status;		return status;
	}		}


	/*		/*
	* This function starts the temperature measurement and returns the value		* This function starts the temperature measurement and returns the value
	* in tenth of a degree celsius.		* in tenth of a degree celsius.
	@@ -205,7 +200,7 @@ static s32 bmp085_get_temperature(struct bmp085_data data, int temperature)
	int status;		int status;

	status = bmp085_update_raw_temperature(data);		status = bmp085_update_raw_temperature(data);
	if (status != 0)		if (status < 0)
	goto exit;		goto exit;

	x1 = ((data->raw_temperature - cali->AC6) * cali->AC5) >> 15;		x1 = ((data->raw_temperature - cali->AC6) * cali->AC5) >> 15;
	@@ -222,8 +217,10 @@ exit:
	/*		/*
	* This function starts the pressure measurement and returns the value		* This function starts the pressure measurement and returns the value
	* in millibar. Since the pressure depends on the ambient temperature,		* in millibar. Since the pressure depends on the ambient temperature,
	* a temperature measurement is executed if the last known value is older		* a temperature measurement is executed according to the given temperature
	* than one second.		* measurement period (default is 1 sec boundary). This period could vary
			* and needs to be adjusted according to the sensor environment, i.e. if big
			* temperature variations then the temperature needs to be read out often.
	*/		*/
	static s32 bmp085_get_pressure(struct bmp085_data data, int pressure)		static s32 bmp085_get_pressure(struct bmp085_data data, int pressure)
	{		{
	@@ -234,16 +231,16 @@ static s32 bmp085_get_pressure(struct bmp085_data data, int pressure)
	int status;		int status;

	/* alt least every second force an update of the ambient temperature */		/* alt least every second force an update of the ambient temperature */
	if (data->last_temp_measurement == 0 \|\|		if ((data->last_temp_measurement == 0) \|\|
	time_is_before_jiffies(data->last_temp_measurement + 1*HZ)) {		time_is_before_jiffies(data->last_temp_measurement + 1*HZ)) {
	status = bmp085_get_temperature(data, NULL);		status = bmp085_get_temperature(data, NULL);
	if (status != 0)		if (status < 0)
	goto exit;		return status;
	}		}

	status = bmp085_update_raw_pressure(data);		status = bmp085_update_raw_pressure(data);
	if (status != 0)		if (status < 0)
	goto exit;		return status;

	x1 = (data->b6 * data->b6) >> 12;		x1 = (data->b6 * data->b6) >> 12;
	x1 *= cali->B2;		x1 *= cali->B2;
	@@ -274,15 +271,14 @@ static s32 bmp085_get_pressure(struct bmp085_data data, int pressure)

	*pressure = p;		*pressure = p;

	exit:		return 0;
	return status;
	}		}

	/*		/*
	* This function sets the chip-internal oversampling. Valid values are 0..3.		* This function sets the chip-internal oversampling. Valid values are 0..3.
	* The chip will use 2^oversampling samples for internal averaging.		* The chip will use 2^oversampling samples for internal averaging.
	* This influences the measurement time and the accuracy; larger values		* This influences the measurement time and the accuracy; larger values
	* increase both. The datasheet gives on overview on how measurement time,		* increase both. The datasheet gives an overview on how measurement time,
	* accuracy and noise correlate.		* accuracy and noise correlate.
	*/		*/
	static void bmp085_set_oversampling(struct bmp085_data *data,		static void bmp085_set_oversampling(struct bmp085_data *data,
	@@ -309,12 +305,16 @@ static ssize_t set_oversampling(struct device *dev,
	struct i2c_client *client = to_i2c_client(dev);		struct i2c_client *client = to_i2c_client(dev);
	struct bmp085_data *data = i2c_get_clientdata(client);		struct bmp085_data *data = i2c_get_clientdata(client);
	unsigned long oversampling;		unsigned long oversampling;
	int success = strict_strtoul(buf, 10, &oversampling);		int err = kstrtoul(buf, 10, &oversampling);
	if (success == 0) {
			if (err == 0) {
			mutex_lock(&data->lock);
	bmp085_set_oversampling(data, oversampling);		bmp085_set_oversampling(data, oversampling);
			mutex_unlock(&data->lock);
	return count;		return count;
	}		}
	return success;
			return err;
	}		}

	static ssize_t show_oversampling(struct device *dev,		static ssize_t show_oversampling(struct device *dev,
	@@ -322,6 +322,7 @@ static ssize_t show_oversampling(struct device *dev,
	{		{
	struct i2c_client *client = to_i2c_client(dev);		struct i2c_client *client = to_i2c_client(dev);
	struct bmp085_data *data = i2c_get_clientdata(client);		struct bmp085_data *data = i2c_get_clientdata(client);

	return sprintf(buf, "%u\n", bmp085_get_oversampling(data));		return sprintf(buf, "%u\n", bmp085_get_oversampling(data));
	}		}
	static DEVICE_ATTR(oversampling, S_IWUSR \| S_IRUGO,		static DEVICE_ATTR(oversampling, S_IWUSR \| S_IRUGO,
	@@ -337,7 +338,7 @@ static ssize_t show_temperature(struct device *dev,
	struct bmp085_data *data = i2c_get_clientdata(client);		struct bmp085_data *data = i2c_get_clientdata(client);

	status = bmp085_get_temperature(data, &temperature);		status = bmp085_get_temperature(data, &temperature);
	if (status != 0)		if (status < 0)
	return status;		return status;
	else		else
	return sprintf(buf, "%d\n", temperature);		return sprintf(buf, "%d\n", temperature);
	@@ -354,7 +355,7 @@ static ssize_t show_pressure(struct device *dev,
	struct bmp085_data *data = i2c_get_clientdata(client);		struct bmp085_data *data = i2c_get_clientdata(client);

	status = bmp085_get_pressure(data, &pressure);		status = bmp085_get_pressure(data, &pressure);
	if (status != 0)		if (status < 0)
	return status;		return status;
	else		else
	return sprintf(buf, "%d\n", pressure);		return sprintf(buf, "%d\n", pressure);
	@@ -386,21 +387,19 @@ static int bmp085_detect(struct i2c_client client, struct i2c_board_info info)

	static int bmp085_init_client(struct i2c_client *client)		static int bmp085_init_client(struct i2c_client *client)
	{		{
	unsigned char version;
	int status;
	struct bmp085_data *data = i2c_get_clientdata(client);		struct bmp085_data *data = i2c_get_clientdata(client);
			int status = bmp085_read_calibration_data(client);

			if (status < 0)
			return status;

	data->client = client;		data->client = client;
	status = bmp085_read_calibration_data(client);
	if (status != 0)
	goto exit;
	version = i2c_smbus_read_byte_data(client, BMP085_VERSION_REG);
	data->last_temp_measurement = 0;		data->last_temp_measurement = 0;
			data->temp_measurement_period = 1*HZ;
	data->oversampling_setting = 3;		data->oversampling_setting = 3;
	mutex_init(&data->lock);		mutex_init(&data->lock);
	dev_info(&data->client->dev, "BMP085 ver. %d.%d found.\n",
	(version & 0x0F), (version & 0xF0) >> 4);		return 0;
	exit:
	return status;
	}		}

	static int __devinit bmp085_probe(struct i2c_client *client,		static int __devinit bmp085_probe(struct i2c_client *client,
	@@ -415,14 +414,11 @@ static int __devinit bmp085_probe(struct i2c_client *client,
	goto exit;		goto exit;
	}		}

	/* default settings after POR */
	data->oversampling_setting = 0x00;

	i2c_set_clientdata(client, data);		i2c_set_clientdata(client, data);

	/* Initialize the BMP085 chip */		/* Initialize the BMP085 chip */
	err = bmp085_init_client(client);		err = bmp085_init_client(client);
	if (err != 0)		if (err < 0)
	goto exit_free;		goto exit_free;

	/* Register sysfs hooks */		/* Register sysfs hooks */
	@@ -430,8 +426,9 @@ static int __devinit bmp085_probe(struct i2c_client *client,
	if (err)		if (err)
	goto exit_free;		goto exit_free;

	dev_info(&data->client->dev, "Successfully initialized bmp085!\n");		dev_info(&client->dev, "Successfully initialized %s!\n", BMP085_NAME);
	goto exit;
			return 0;

	exit_free:		exit_free:
	kfree(data);		kfree(data);
	@@ -441,13 +438,16 @@ exit:

	static int __devexit bmp085_remove(struct i2c_client *client)		static int __devexit bmp085_remove(struct i2c_client *client)
	{		{
			struct bmp085_data *data = i2c_get_clientdata(client);

	sysfs_remove_group(&client->dev.kobj, &bmp085_attr_group);		sysfs_remove_group(&client->dev.kobj, &bmp085_attr_group);
	kfree(i2c_get_clientdata(client));		kfree(data);

	return 0;		return 0;
	}		}

	static const struct i2c_device_id bmp085_id[] = {		static const struct i2c_device_id bmp085_id[] = {
	{ "bmp085", 0 },		{ BMP085_NAME, 0 },
	{ }		{ }
	};		};
	MODULE_DEVICE_TABLE(i2c, bmp085_id);		MODULE_DEVICE_TABLE(i2c, bmp085_id);
	@@ -455,7 +455,7 @@ MODULE_DEVICE_TABLE(i2c, bmp085_id);
	static struct i2c_driver bmp085_driver = {		static struct i2c_driver bmp085_driver = {
	.driver = {		.driver = {
	.owner = THIS_MODULE,		.owner = THIS_MODULE,
	.name = "bmp085"		.name = BMP085_NAME
	},		},
	.id_table = bmp085_id,		.id_table = bmp085_id,
	.probe = bmp085_probe,		.probe = bmp085_probe,
	@@ -467,6 +467,6 @@ static struct i2c_driver bmp085_driver = {

	module_i2c_driver(bmp085_driver);		module_i2c_driver(bmp085_driver);

	MODULE_AUTHOR("Christoph Mair <christoph.mair@gmail.com");		MODULE_AUTHOR("Christoph Mair <christoph.mair@gmail.com>");
	MODULE_DESCRIPTION("BMP085 driver");		MODULE_DESCRIPTION("BMP085 driver");
	MODULE_LICENSE("GPL");		MODULE_LICENSE("GPL");