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 documentation on the state `GPIO_DISCONNECT` was a bit vague. The
API doc said it should disconnect the GPIO from all peripherals, the
test also tested them for being electrically disconnected.
The documentation in both the test and the API is extended to point out
that a GPIO indeed SHOULD be in high impedance state, but that user
MUST NOT expect that this requested is honored by every implementation
and for every GPIO pin.
In the test it is also pointed out that failing the test for a GPIO
in the `GPIO_DISCONNECT` state being electrically disconnected is for
some pins expected, and that the test should be just run again with
different GPIOs. The test intentionally tests for a feature not provided
by every GPIO pin rather than warning on a failure: The effort to just
flash and run the test again with different GPIOs is relatively low, but
it does confirm correct behavior of the API.
This commit optimizes the `gpio_conf_t` type in the following
regards:
- The "base" `gpio_conf_t` is stripped from members that only some
platforms support, e.g. drive strength, slew rate, and disabling of
the Schmitt Trigger are no longer universally available but
platform-specific extensions
- The `gpio_conf_t` is now crammed into a bit-field that is 8 bit or
16 bit wide. This allows for storing lots of them e.g. in
`driver_foo_params_t` or `uart_conf_t` etc.
- A `union` of the `struct` with bit-field members and a `bits` is used
to allow accessing all bits in a simple C statement and to ensure
alignment for efficient handling of the type
Co-authored-by: Gunar Schorcht <gunar@schorcht.net>
Parameter `num` of `mtd_write_page_raw` is the number of bytes to be written, which is the number of sectors to be written`count` multiplied by the pages per sector `mtd->pages_per_sector` and the page size `mtd->page_size`.
Assertions are used instead of returning a NULL pointer to detect errors in the MTD definition and access in the case that the return value is not evaluated.
Allow accessing supported timer frequencies with a dedicated API.
This API needs to be implemented per platform and is available with
the feature periph_timer_query_freqs.
