dt_bindings: rs485: Add receiver enable polarity

Add polarity property for receiver enable. Some UARTs have separate
enable pins for tx (RTS or DE) and rx (RE). As most RS485 transceivers
have !RE pin, the default is active low in contrast to
rs485-rts-active-low that defaults to active high.

Cc: devicetree@vger.kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220426122448.38997-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ilpo Järvinen 2022-04-26 15:24:41 +03:00 committed by Greg Kroah-Hartman
parent 5ff33917fa
commit 103dcf2ea2

View File

@ -33,6 +33,11 @@ properties:
description: drive RTS low when sending (default is high).
$ref: /schemas/types.yaml#/definitions/flag
rs485-rx-active-high:
description: Polarity of receiver enable signal (when separate from RTS).
True indicates active high (default is low).
$ref: /schemas/types.yaml#/definitions/flag
linux,rs485-enabled-at-boot-time:
description: enables the rs485 feature at boot time. It can be disabled
later with proper ioctl.