diff options
| author | Per-Daniel Olsson <perdaniel.olsson@axis.com> | 2024-12-18 11:48:36 +0100 |
|---|---|---|
| committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2024-12-28 14:28:13 +0000 |
| commit | 0c6db4506ad0259c0decc1eafeb8a6f98487f23a (patch) | |
| tree | a8893875596b80303d21f8137efa01fec2f2a378 /Documentation/iio | |
| parent | 8354dc89242c6c811996536c8d95f9eb97f9f9f1 (diff) | |
| download | linux-next-0c6db4506ad0259c0decc1eafeb8a6f98487f23a.tar.gz linux-next-0c6db4506ad0259c0decc1eafeb8a6f98487f23a.zip | |
iio: light: Add support for TI OPT4060 color sensor
Add support for Texas Instruments OPT4060 RGBW Color sensor.
Signed-off-by: Per-Daniel Olsson <perdaniel.olsson@axis.com>
Link: https://patch.msgid.link/20241218104836.2784523-3-perdaniel.olsson@axis.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'Documentation/iio')
| -rw-r--r-- | Documentation/iio/index.rst | 1 | ||||
| -rw-r--r-- | Documentation/iio/opt4060.rst | 61 |
2 files changed, 62 insertions, 0 deletions
diff --git a/Documentation/iio/index.rst b/Documentation/iio/index.rst index 074dbbf7ba0a..5710f5b9e958 100644 --- a/Documentation/iio/index.rst +++ b/Documentation/iio/index.rst @@ -29,3 +29,4 @@ Industrial I/O Kernel Drivers adxl380 bno055 ep93xx_adc + opt4060 diff --git a/Documentation/iio/opt4060.rst b/Documentation/iio/opt4060.rst new file mode 100644 index 000000000000..eb155089b6d2 --- /dev/null +++ b/Documentation/iio/opt4060.rst @@ -0,0 +1,61 @@ +============================== +OPT4060 driver +============================== + +1. Overview +============================= + +This driver supports the Texas Instrument RGBW high resolution color sensor over +I2C. +https://www.ti.com/lit/gpn/opt4060 + +The driver supports: +- Raw values for red, green, blue and clear. +- Illuminance values. +- Scaled color values for red, green and blue. +- IIO events for thresholds. +- IIO triggered buffer using both its own data ready trigger and triggers from +other drivers. + +2. Illuminance calculation +============================= + +Illuminance is calculated using the wide spectrum green channel. + +lux = GREEN_RAW x 2.15e-3 + +The value is accessed from: +/sys/bus/iio/devices/iio:deviceX/in_illuminance_input + +See section 8.4.5.2 in the data sheet for additional details. + +3. Color scale values +============================= + +The sensor has different sensitivity for the different color components and +compensating factors are exposed from the driver. + +The values are accessed from: +/sys/bus/iio/devices/iio:deviceX/in_intensity_red_scale +/sys/bus/iio/devices/iio:deviceX/in_intensity_green_scale +/sys/bus/iio/devices/iio:deviceX/in_intensity_blue_scale + +A userspace application can multiply the raw values with the scale values so +that for a particular test light source, typically white, the measurement +intensity is the same across the different color channels. This is calculated +in the following way: + +R = RED_RAW x SCALE_RED(2.4) +G = GREEN_RAW x SCALE_GREEN(1.0) +B = BLUE_RAW x SCALE_BLUE(1.3) + +The data sheet suggests using the scaled values to normalize the scaled R, G +and B values. This is useful to get a value for the ratio between colors +independent of light intensity. A userspace application can do this in the +following way: + +R_NORMALIZED = R / (R + G + B) +G_NORMALIZED = G / (R + G + B) +B_NORMALIZED = B / (R + G + B) + +See section 8.4.5.2 in the data sheet for additional details. |