serial: 8250: Deduplicate ->rs485_config() callback

Commit e490c9144cfa ("tty: Add software emulated RS485 support for 8250")
introduced support to use RTS as an rs485 Transmit Enable signal.
Drivers opt in to the feature by calling serial8250_em485_init() from
their ->rs485_config() callback.

So far there are two drivers doing that, 8250_omap.c and 8250_of.c.
Both use an identical callback.  We're about to add a third user of that
callback, therefore deduplicate it and move it to 8250_port.c.

Drivers now opt in to rs485 software emulation by assigning the generic
serial8250_rs485_config() callback introduced herein to their
.rs485_config struct member.  This change allows unexporting
serial8250_em485_init() and declaring it static.

Signed-off-by: Lukas Wunner <[email protected]>
Cc: Matwey V. Kornilov <[email protected]>
Cc: Heiko Schocher <[email protected]>
Link: https://lore.kernel.org/r/fcef63642dc4eae41ae7842d23747b2bf5d40285.1582895077.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <[email protected]>

0 files changed, 0 insertions, 0 deletions