staging: iio: cleanup and move comments in hmc5843

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Peter Meerwald 2012-05-17 02:28:10 +02:00 committed by Greg Kroah-Hartman
parent e278df1c82
commit c7c34af049

View file

@ -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",
@ -130,18 +155,16 @@ static const unsigned short normal_i2c[] = { HMC5843_I2C_ADDRESS,
/* Each client has this additional data */
struct hmc5843_data {
struct mutex lock;
u8 rate;
u8 meas_conf;
u8 operating_mode;
u8 range;
u8 rate;
u8 meas_conf;
u8 operating_mode;
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);
@ -166,23 +189,22 @@ static int hmc5843_read_measurement(struct iio_dev *indio_dev,
if (result < 0)
return -EINVAL;
*val = (s16)swab16((u16)result);
*val = (s16)swab16((u16)result);
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.
* 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);
@ -392,31 +405,19 @@ static ssize_t show_sampling_frequency(struct device *dev,
struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
s32 rate;
rate = i2c_smbus_read_byte_data(client, this_attr->address);
rate = i2c_smbus_read_byte_data(client, this_attr->address);
if (rate < 0)
return rate;
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: