Zephyr UART drivers offer very low-level functionality. Oftentimes,
it would be useful to provide higher-level wrappers around UART
device which would offer additional functionality. However, UART
driver irq callback routine receives just a pointer to (low-level)
UART device, and it's not possible to get to a wrapper structure
(without introducing expensive external mapping structures). This
is an indirect reason why the current UARt wrappers - uart_pipe,
console - are instantiated statically just for one underlying UART
device and cannot be reused for multiple devices.
Solve this by allowing to pass an arbitrary user data to irq
callback, set by new uart_irq_callback_user_data_set() function.
Existing uart_irq_callback_set() keeps setting a callback which
will receive pointer to the device.
While public API maintains compatibility, drivers themselves need
to be updated to support arbitrary user data storage/passing (as
legacy uart_irq_callback_set() functionality is now implemented in
terms of it).
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
There are some minor differences between the UART om SAMD20 and SAMD21
that we need to take into account:
SYNCBUSY bit for the samd20 is located in the STATUS reg.
The samd20 does not have a SAMPR bit like the samd21.
Signed-off-by: Sean Nyekjaer <sean@nyekjaer.dk>
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Also pull out the SERCOM pads configuration to defines. Note that the
SAM0 has a two level configuration - a signal (like TX) is mapped to a
pad, and then a pad is mapped to a function on a pin.
Signed-off-by: Michael Hope <mlhx@google.com>
