Sun Sensor Driver Reference¶

Out of date

This page predates the current quad-backend driver model. See Driver Model for how drivers are structured today.

Design¶

Sun Sensors work well in integrating with Zephyr's Sensor API, which is just a standardized set of driver API functions. The only aspect that really needs to be custom is that there is not a Sensor Channel for sun angles, so we need to have a custom one.

Internals¶

Custom Sensor Channels¶

enum my_sensor_channel {
    SENSOR_CHAN_SUN_ANGLE_XY = SENSOR_CHAN_PRIV_START,
};

Though not custom, we may also be using SENSOR_CHAN_LUX if supported on our sun sensor

API¶

const struct device *dev is an implied parameter for all but the initialization function

int init_sun_sensor()¶

Description¶

Any required hardware or communication bus initialization goes here

Parameters¶

TODO: Identify configuration parameters

Return¶

An integer status code

Code	Status Category	Description
0	Success	Initialzed successfully
-EIO	Error	Communication Error
-ENODEV	Error	Could not find device
-1	Error	Additional Errors TBD

int sample_fetch(enum sensor_channel channel)¶

Description¶

Pulls sun sensor data from hardware into driver's SRAM

Parameters¶

enum sensor_channel channel - Which of the custom sensor channels to read

Return¶

An integer status code

Code	Status Category	Description
0	Success	Initialzed successfully
-ENOTSUP	Error	Sensor channel requested is not supported
-1	Error	Additional Errors TBD

int channel_get(enum sensor_channel channel, struct sensor_value *val)¶

Description¶

Formats the hardware data (in driver SRAM from sample_fetch) into the sensor_value format for specified channel

Parameters¶

enum sensor_channel channel - Which of the custom sensor channels to write to *val

struct sensor_value *val - Memory pointer to load requested value into

Return¶

An integer status code

Code	Status Category	Description
0	Success	Initialzed successfully
-ENOTSUP	Error	Sensor channel requested is not supported
-1	Error	Additional Errors TBD