/** \brief Find a sensor hardware descriptor
*
* This routine returns the address of a sensor hardware descriptor, based on
* the sensor type specified in the \c type parameter. The first hardware
* entry with the correct type will be used.
*
* This utility is currently used to abstract the details of the device list
* implementation from the rest of the API. However, it will not be retained in
* future versions of the API. As a result applications and library code should
* not use this routine. If list iteration is required in API clients, use the
* sensor_device_enum() function.
*
* \param type The type of sensor to find in hardware descriptor list
*
* \return The address of the sensor hardware descriptor, or NULL if not found
*/
sensor_hal_t *sensor_find(sensor_type_t type)
{
size_t dev_count;
sensor_hal_t *const dev_list = sensor_list(&dev_count);
/* Find the specified sensor type in the device list. */
for (int index = 0; index < dev_count; ++index) {
/* Test device against input type(s) bitmask. */
if ((dev_list[index].dev_type & type) == type) {
return &dev_list [index];
}
}
return 0;
}
/**
* @brief Enumerate sensor devices.
*
* This routine is a sensor device enumeration function that will call a
* user-defined callback \c func for each sensor of a specified \c type
* configured into the system. The user-callback function will be passed the
* address of a \a sensor_hal_t \c HAL descriptor corresponding to the sensor
* type along with a user-specified address \c arg storing any additional
* function arguments.
*
* If the specified sensor \c type is \c SENSOR_TYPE_UNKNOWN, then the user
* \c func will be called for every sensor device in the system.
*
* Once called, the user-callback function must return a boolean \a true
* value to continue iterating the list, else \a false to cease device list
* iteration. This routine returns when there are not more sensors of the
* requested \c type in the device list, or when the user function returns
* zero (false).
*
* Note that this function will not be included in the API by default. Build
* a sensor system with \c INCLUDE_SENSOR_ENUM defined to include this routine.
*
* @param type Specifies the sensor type to enumerate.
* @param func Specifies the address of a user callback function.
* @param arg Specifies the address of a callback function argument.
* @return bool true if the call succeeds, else false is returned.
*/
bool sensor_device_enum
(sensor_type_t type, sensor_enum_callback func, void *arg)
{
#ifdef INCLUDE_SENSOR_ENUM
size_t count;
const sensor_hal_t *hal = sensor_list(&count);
if (func != 0) {
for (int n = 0; n < count; ++n, ++hal) {
if (((type == SENSOR_TYPE_UNKNOWN) ||
(type == hal->dev_type)) &&
(false == (func)(hal, arg))) {
return true;
}
}
}
#endif /* INCLUDE_SENSOR_ENUM */
return false;
}
