staging: iio: light sensor: Add a calibscale file to the isl29018 light sensor driver.

Defaulting to 1, this gives a way to amplify the lux value before being
reduced by the programmed adc_bit shift.
Only support whole numbers right now.  When this driver is converted to the new
IIO_CHAN framework, it will be easy to support the framework's pseudo float.

Add illuminance0_calibscale documentation to sysfs-bus-iio-light.

Signed-off-by: Bryan Freed <bfreed@chromium.org>
Acked-by: Rhyland Klein <rklein@nvidia.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Bryan Freed 2011-06-28 16:46:33 -07:00 committed by Greg Kroah-Hartman
parent 03bda05d9c
commit 6d1ad0f8aa
2 changed files with 42 additions and 1 deletions

View file

@ -75,3 +75,11 @@ KernelVersion: 2.6.37
Contact: linux-iio@vger.kernel.org
Description:
This property gets/sets the sensors ADC analog integration time.
What: /sys/bus/iio/devices/device[n]/illuminance0_calibscale
KernelVersion: 2.6.37
Contact: linux-iio@vger.kernel.org
Description:
Hardware or software applied calibration scale factor assumed
to account for attenuation due to industrial design (glass
filters or aperture holes).

View file

@ -56,6 +56,7 @@
struct isl29018_chip {
struct i2c_client *client;
struct mutex lock;
unsigned int lux_scale;
unsigned int range;
unsigned int adc_bit;
int prox_scheme;
@ -165,7 +166,7 @@ static int isl29018_read_lux(struct i2c_client *client, int *lux)
if (lux_data < 0)
return lux_data;
*lux = (lux_data * chip->range) >> chip->adc_bit;
*lux = (lux_data * chip->range * chip->lux_scale) >> chip->adc_bit;
return 0;
}
@ -263,6 +264,34 @@ static ssize_t get_sensor_data(struct device *dev, char *buf, int mode)
}
/* Sysfs interface */
/* lux_scale */
static ssize_t show_lux_scale(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct isl29018_chip *chip = indio_dev->dev_data;
return sprintf(buf, "%d\n", chip->lux_scale);
}
static ssize_t store_lux_scale(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct isl29018_chip *chip = indio_dev->dev_data;
unsigned long lval;
lval = simple_strtoul(buf, NULL, 10);
if (lval == 0)
return -EINVAL;
mutex_lock(&chip->lock);
chip->lux_scale = lval;
mutex_unlock(&chip->lock);
return count;
}
/* range */
static ssize_t show_range(struct device *dev,
struct device_attribute *attr, char *buf)
@ -411,6 +440,8 @@ static IIO_DEVICE_ATTR(proximity_on_chip_ambient_infrared_supression,
show_prox_infrared_supression,
store_prox_infrared_supression, 0);
static IIO_DEVICE_ATTR(illuminance0_input, S_IRUGO, show_lux, NULL, 0);
static IIO_DEVICE_ATTR(illuminance0_calibscale, S_IRUGO | S_IWUSR,
show_lux_scale, store_lux_scale, 0);
static IIO_DEVICE_ATTR(intensity_infrared_raw, S_IRUGO, show_ir, NULL, 0);
static IIO_DEVICE_ATTR(proximity_raw, S_IRUGO, show_proxim_ir, NULL, 0);
@ -423,6 +454,7 @@ static struct attribute *isl29018_attributes[] = {
ISL29018_CONST_ATTR(adc_resolution_available),
ISL29018_DEV_ATTR(proximity_on_chip_ambient_infrared_supression),
ISL29018_DEV_ATTR(illuminance0_input),
ISL29018_DEV_ATTR(illuminance0_calibscale),
ISL29018_DEV_ATTR(intensity_infrared_raw),
ISL29018_DEV_ATTR(proximity_raw),
NULL
@ -479,6 +511,7 @@ static int __devinit isl29018_probe(struct i2c_client *client,
mutex_init(&chip->lock);
chip->lux_scale = 1;
chip->range = 1000;
chip->adc_bit = 16;