Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 6697f1f8 authored by Jan Kiszka's avatar Jan Kiszka
Browse files

serial: uapi: Add support for bus termination 



The Siemens IOT2040 comes with a RS485 interface that allows to enable
or disable bus termination via software. Add a bit to the flags field of
serial_rs485 that applications can set in order to request this feature
from the hardware. This seems generic enough to add it for everyone.
Existing driver will simply ignore it when set.

Signed-off-by: default avatarSascha Weisenberger <sascha.weisenberger@siemens.com>
Signed-off-by: default avatarJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 85bb4646

include/uapi/linux/serial.h

+3 −0
Original line number Diff line number Diff line
@@ -122,6 +122,9 @@ struct serial_rs485 { 
#define SER_RS485_RTS_AFTER_SEND	(1 << 2)	/* Logical level for

							   RTS pin after sent*/

#define SER_RS485_RX_DURING_TX		(1 << 4)

#define SER_RS485_TERMINATE_BUS		(1 << 5)	/* Enable bus

							   termination

							   (if supported) */

	__u32	delay_rts_before_send;	/* Delay before send (milliseconds) */

	__u32	delay_rts_after_send;	/* Delay after send (milliseconds) */

	__u32	padding[5];		/* Memory is cheap, new structs