This pulls in embedded-nal 0.7 implementations, and (on both crates)
alterations that decouple riot-wrappers from riot-sys and simplify build
system integration, and do away with the need for passing
RIOT_USEMODULE.
The checks would print their prominently colored warnings and confuse
users, and the comments are more geared to those editing the Makefiles
than to those watching which commands get executed.
Back when specific control of the Rust version used with RIOT was
needed, CARGO_CHANNEL was added to explicitly set the Rust version with
consideration for CI special cases.
Rust's mechansims of selecting a toolchain can be used instead now.
The tramp assembly was missing a `.note.GNU-stack` section,
meaning the compiler was forced to assume that we require
an executable stack.
Fix this by adding the necessary section.
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Note that for the very CPU this driver is used with (nRF52 on the
microbit-v2 board), this currently needs extra workarounds to copy
written data from flash to RAM so that the driver can see it. (Otherwise
it silently writes 00, and then correctly reads 00 from the bus all the
time).
The underlying peripheral can only read from RAM. This uses the
existing infrastructure (already needed to work around the lack of a
hardware support for I2C_NOSTART) to unconditionally copy any to-be-sent
data into RAM.
- Move common code for USART (shared SPI / UART peripheral) to its
own file and allow sharing the USART peripheral to provide both
UART and SPI in round-robin fashion.
- Configure both UART and SPI bus via a `struct` in the board's
`periph_conf.h`
- this allows allocating the two UARTs as needed by the use case
- since both USARTs signals have a fixed connection to a single
GPIO, most configuration is moved to the CPU
- the board now only needs to decide which bus is provided by
which USART
Note: Sharing an USART used as UART requires cooperation from the app:
- If the UART is used in TX-only mode (no RX callback), the driver
will release the USART while not sending
- If the UART is used to also receive, the application needs to power
the UART down while not expecting something to send. An
`spi_acquire()` will be blocked while the UART is powered up.
