uart_irq_tx_empty() function proved to be problematic: its semantics
was not documented properly, and many hardware uses terminology like
"TX register empty" to signify condition of TX register being ready
to accept another character (what in Zephyr is tested with
uart_irq_tx_ready()). To avoid confusion, uart_irq_tx_empty() was
renamed to uart_irq_tx_complete(), propagating to drivers/serial
device methods.
The semantics and usage model of all of uart_irq_rx_ready(),
uart_irq_tx_ready(), uart_irq_tx_complete() is now described in
detail.
Signed-off-by: Paul Sokolovsky <paul.sokolovsky@linaro.org>
Convert code to use u{8,16,32,64}_t and s{8,16,32,64}_t instead of C99
integer types.
Jira: ZEP-2051
Change-Id: I08f51e2bfd475f6245771c1bd2df7ffc744c48c4
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Adds a shim layer around the mcux lpuart driver to adapt it to the Zephyr
serial interface.
NXP has multiple uart hardware blocks that implement different features
and have different register maps. The k64 has a uart block called
'uart', while the kw41 has a uart block called 'lpuart' (low power
uart). The MCUXpresso SDK provides separate drivers for each type of
uart block but with similar software interfaces. As a result, there are
also separate shim drivers in Zephyr. There is a 1:1:1 relationship
between hardware block, mcux driver, and mcux shim driver.
Because we now have two mcux shim drivers for the uart interface, a new
naming convention is created:
<interface>_mcux_<hw block>
Where <interface> is the name of the Zephyr interface, in this case
'uart'. This convention is not new.
<hw block> is the name of the NXP hardware block, in this case 'lpuart'.
This is the new part, and distinguishes different hardware blocks
for the same interface.
Change-Id: I3a80b9bffa116bbb2b02ee950d4bdd79a19a4edc
Signed-off-by: Maureen Helm <maureen.helm@nxp.com>