Commit c7c34af0 authored by Peter Meerwald's avatar Peter Meerwald Committed by Greg Kroah-Hartman
Browse files

staging: iio: cleanup and move comments in hmc5843 



Signed-off-by: default avatarPeter Meerwald <pmeerw@pmeerw.net>
Acked-by: default avatarJonathan Cameron <jic23@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent e278df1c

drivers/staging/iio/magnetometer/hmc5843.c

+63 −59
Original line number Diff line number Diff line
@@ -103,6 +103,18 @@ static const int hmc5843_regval_to_nanoscale[] = { 
	6173, 7692, 10309, 12821, 18868, 21739, 25641, 35714

};



/*

 * From the datasheet:

 * 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 const int regval_to_input_field_mg[] = {

	700,

	1000,
@@ -113,6 +125,19 @@ static const int regval_to_input_field_mg[] = { 
	4500,

	6500

};



/*

 * From the datasheet:

 * Value	| Data output rate (Hz)

 * 0		| 0.5

 * 1		| 1

 * 2		| 2

 * 3		| 5

 * 4		| 10 (default)

 * 5		| 20

 * 6		| 50

 * 7		| Not used

 */

static const char * const regval_to_samp_freq[] = {

	"0.5",

	"1",
@@ -136,12 +161,10 @@ struct hmc5843_data { 
	u8 range;

};



static void hmc5843_init_client(struct i2c_client *client);



/* The lower two bits contain the current conversion mode */

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 & HMC5843_MODE_MASK);
@@ -170,19 +193,18 @@ static int hmc5843_read_measurement(struct iio_dev *indio_dev, 
	return IIO_VAL_INT;

}





/*

 * From the datasheet

 * From the datasheet:

 * 0 - Continuous-Conversion Mode: In continuous-conversion mode, the

 * device continuously performs conversions and places the result in the

 * data register.

 *     device continuously performs conversions and places the result in

 *     the data register.

 *

 * 1 - Single-Conversion Mode : device performs a single measurement,

 *  sets RDY high and returned to sleep mode

 * 1 - Single-Conversion Mode : Device performs a single measurement,

 *     sets RDY high and returns to sleep mode.

 *

 * 2 - Idle Mode : Device is placed in idle mode.

 *

 * 3 - Sleep Mode. Device is placed in sleep mode.

 * 3 - Sleep Mode : Device is placed in sleep mode.

 *

 */

static ssize_t hmc5843_show_operating_mode(struct device *dev,
@@ -206,13 +228,14 @@ static ssize_t hmc5843_set_operating_mode(struct device *dev, 
	unsigned long operating_mode = 0;

	s32 status;

	int error;



	mutex_lock(&data->lock);

	error = kstrtoul(buf, 10, &operating_mode);

	if (error) {

		count = error;

		goto exit;

	}

	dev_dbg(dev, "set Conversion mode to %lu\n", operating_mode);

	dev_dbg(dev, "set conversion mode to %lu\n", operating_mode);

	if (operating_mode > HMC5843_MODE_SLEEP) {

		count = -EINVAL;

		goto exit;
@@ -230,6 +253,7 @@ static ssize_t hmc5843_set_operating_mode(struct device *dev, 
	mutex_unlock(&data->lock);

	return count;

}



static IIO_DEVICE_ATTR(operating_mode,

			S_IWUSR | S_IRUGO,

			hmc5843_show_operating_mode,
@@ -239,17 +263,19 @@ static IIO_DEVICE_ATTR(operating_mode, 
/*

 * 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.

 * From the datasheet:

 * 0 - 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.

 * 1 - 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.

 * 2 - 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,
@@ -290,8 +316,7 @@ static ssize_t hmc5843_set_measurement_configuration(struct device *dev, 
		return -EINVAL;



	mutex_lock(&data->lock);



	dev_dbg(dev, "set mode to %lu\n", meas_conf);

	dev_dbg(dev, "set measurement configuration to %lu\n", meas_conf);

	if (hmc5843_set_meas_conf(client, meas_conf)) {

		count = -EINVAL;

		goto exit;
@@ -302,25 +327,13 @@ static ssize_t hmc5843_set_measurement_configuration(struct device *dev, 
	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_SAMP_FREQ_AVAIL("0.5 1 2 5 10 20 50");



static s32 hmc5843_set_rate(struct i2c_client *client,
@@ -333,7 +346,7 @@ static s32 hmc5843_set_rate(struct i2c_client *client, 
	reg_val = (data->meas_conf) |  (rate << HMC5843_RATE_OFFSET);

	if (rate >= HMC5843_RATE_NOT_USED) {

		dev_err(&client->dev,

			"This data output rate is not supported\n");

			"data output rate is not supported\n");

		return -EINVAL;

	}

	return i2c_smbus_write_byte_data(client, HMC5843_CONFIG_REG_A, reg_val);
@@ -398,25 +411,13 @@ static ssize_t show_sampling_frequency(struct device *dev, 
	rate = (rate & HMC5843_RATE_BITMASK) >> HMC5843_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)
@@ -440,6 +441,7 @@ static ssize_t set_range(struct device *dev, 
	struct hmc5843_data *data = iio_priv(indio_dev);

	unsigned long range = 0;

	int error;



	mutex_lock(&data->lock);

	error = kstrtoul(buf, 10, &range);

	if (error) {
@@ -461,8 +463,8 @@ static ssize_t set_range(struct device *dev, 
exit:

	mutex_unlock(&data->lock);

	return count;



}



static IIO_DEVICE_ATTR(in_magn_range,

			S_IWUSR | S_IRUGO,

			show_range,
@@ -537,7 +539,7 @@ static int hmc5843_detect(struct i2c_client *client, 
	return 0;

}



/* Called when we have found a new HMC5843. */

/* Called when we have found a new HMC5843 */

static void hmc5843_init_client(struct i2c_client *client)

{

	struct iio_dev *indio_dev = i2c_get_clientdata(client);
@@ -548,6 +550,7 @@ static void hmc5843_init_client(struct i2c_client *client) 
	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");

}
@@ -577,8 +580,6 @@ static int hmc5843_probe(struct i2c_client *client, 
	data->operating_mode = HMC5843_MODE_CONVERSION_CONTINUOUS;



	i2c_set_clientdata(client, indio_dev);



	/* Initialize the HMC5843 chip */

	hmc5843_init_client(client);



	indio_dev->info = &hmc5843_info;
@@ -587,10 +588,13 @@ static int hmc5843_probe(struct i2c_client *client, 
	indio_dev->num_channels = ARRAY_SIZE(hmc5843_channels);

	indio_dev->dev.parent = &client->dev;

	indio_dev->modes = INDIO_DIRECT_MODE;



	err = iio_device_register(indio_dev);

	if (err)

		goto exit_free2;



	return 0;



exit_free2:

	iio_device_free(indio_dev);

exit: