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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /Documentation/ABI/testing/sysfs-bus-iio-isl29501
parentInitial commit. (diff)
downloadlinux-c109f8d9e922037b3fa45f46d78384d49db8ad76.tar.xz
linux-c109f8d9e922037b3fa45f46d78384d49db8ad76.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+What: /sys/bus/iio/devices/iio:deviceX/in_proximity0_agc_gain
+What: /sys/bus/iio/devices/iio:deviceX/in_proximity0_agc_gain_bias
+KernelVersion: 4.18
+Contact: linux-iio@vger.kernel.org
+Description:
+ This sensor has an automatic gain control (agc) loop
+ which sets the analog signal levels at an optimum
+ level by controlling programmable gain amplifiers. The
+ criteria for optimal gain is determined by the sensor.
+
+ Return the actual gain value as an integer in [0; 65536]
+ range when read from.
+
+ The agc gain read when measuring crosstalk shall be
+ written into in_proximity0_agc_gain_bias.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_proximity0_calib_phase_temp_a
+What: /sys/bus/iio/devices/iio:deviceX/in_proximity0_calib_phase_temp_b
+What: /sys/bus/iio/devices/iio:deviceX/in_proximity0_calib_phase_light_a
+What: /sys/bus/iio/devices/iio:deviceX/in_proximity0_calib_phase_light_b
+KernelVersion: 4.18
+Contact: linux-iio@vger.kernel.org
+Description:
+ The sensor is able to perform correction of distance
+ measurements due to changing temperature and ambient
+ light conditions. It can be programmed to correct for
+ a second order error polynomial.
+
+ Phase data has to be collected when temperature and
+ ambient light are modulated independently.
+
+ Then a least squares curve fit to a second order
+ polynomial has to be generated from the data. The
+ resultant curves have the form ax^2 + bx + c.
+
+ From those two curves, a and b coefficients shall be
+ stored in in_proximity0_calib_phase_temp_a and
+ in_proximity0_calib_phase_temp_b for temperature and
+ in in_proximity0_calib_phase_light_a and
+ in_proximity0_calib_phase_light_b for ambient light.
+
+ Those values must be integer in [0; 8355840] range.
+
+ Finally, the c constant is set by the sensor
+ internally.
+
+ The value stored in sensor is displayed when read from.