Some periph_rtt implementations do not provide `rtt_set_counter()`. This
adds `periph_rtt_set_counter` as feature to allow testing for its
availability. The feature is provided at CPU level if periph_rtt is
provided by the board for all CPUs implementing `rtt_set_counter()`.
The clock adjustment API only used a 16 bit integer for speed correction. This
is to course grained to allow compensating clock drifts at high accuracy.
Using a 32 bit integer instead would allow to fix for a drift of up to
about 1 nanosecond drift per each 5 seconds.
That ought to be enough for anyone! (*cough* *cough*)
- Use negative errno as error codes, rather than home-grown enums
- Update the home-grown enum with negative errno codes for backward
compatibility and mark it deprecated
- Update API doc to use negative errno codes
- Fix various style issues in Doxygen doc
- Use `@retval` to document specific return values instead of abusing
`@return` for this
- Align parameters to proper indent level
The driver uses the netdev interface. Due to the limited
capabilities of the transceiver (32 byte FIFO and no source address in the layer2 frame),
it relies on 6LowPAN compression and adds the source address to the frame for that.
Changed the API of `netdev_driver_t`:
- The `send()` function should no longer return the number of bytes and should
not block
- The upper layer now must call the new `confirm_send()` function after
calling `send()`; either busy waiting until something different to `-EBUSY`
is returned, or after `NETDEV_EVENT_TX_COMPLETE` was signaled
During transition to the new API, the upper layer must remain backward
compatible and must assume the legacy API if `netdev_driver_t::confirm_send()`
is `NULL`.
The SI1133 from Silicon Labs is a UV Index Sensor and Ambient Light
Sensor in a small 2x2 mm DFN package. The sensor can measure
independently ultra violet (UV) light, infra red (IR) light and
ambient light, however the ambient light is also influenced by the
IR light requiring compensation from the IR readings.
The SI1133 is quite different from other Silicon Labs chips in RIOT OS
and therefore needs its own driver. In particular, the SI1133 has 7
different photodiode configurations to read but only 6 channels to
read them in parallel so only some channels can be read each time.
This patch implements a new driver allowing to read the data directly
and a saul interface for the three kinds of light source. There are
many configuration options including interrupts and continous modes
that are left out of this initial driver.
