The default driver type is just an index into a device array defined
by the board.
If a platform wants to encode additional information in the device type,
it can define a custom type.
This means we can just set the default type to whatever fits the target
CPU best.
On ARM this will still be a 32 bit word, but on AVR it will by a 8 bit byte.
Some terminology issues are fixed. (The speed of an UART interface is
the symbol rate. The unit it is measured in is baud, which is symbols
per second. There is no such thing as baudrate or even baud/s.)
The return codes are changed to use negative errno constants on error
to match the driver design rules. For backward compatibility, the
enum was updated to match the error codes. Unless an application
depends on the exact numerical value (which would be insane), this is
not breaking any code.
Change description to reflect the configurability of the serial
interface.
Also, fix the uart_mode parameter description as the UART will be
configured and not initialized.
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
As suggested in PR#5899 add a routine uart_mode() that will
setup data bits, stop bits and parity at runtime.
uart.h provides a set of enums defining these settings and each
platform will override them to specify values corresponding to
its configuration registers.
The idea behind the enums is to specify default settings i.e. 8N1
through the 0 value item. Invoking uart_mode(uart, 0, 0, 0) will
setup 8N1 mode.
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
- removed UNDEFINED value from device enum
- added argument for callbacks
- add power[on|off] functions
- removed tx_end() function in favor of cb return value
