Commit 068d35a7 authored by Hugo Villeneuve's avatar Hugo Villeneuve Committed by Greg Kroah-Hartman
Browse files

serial: sc16is7xx: announce support for SER_RS485_RTS_ON_SEND 



When specifying flag SER_RS485_RTS_ON_SEND in RS485 configuration,
we get the following warning after commit 4afeced5 ("serial: core:
fix sanitizing check for RTS settings"):

    invalid RTS setting, using RTS_AFTER_SEND instead

This results in SER_RS485_RTS_AFTER_SEND being set and the
driver always write to the register field SC16IS7XX_EFCR_RTS_INVERT_BIT,
which breaks some hardware using these chips.

The hardware supports both RTS_ON_SEND and RTS_AFTER_SEND modes, so fix
this by announcing support for RTS_ON_SEND.

Signed-off-by: default avatarHugo Villeneuve <hvilleneuve@dimonoff.com>
Suggested-by: default avatarKonstantin Pugin <ria.freelander@gmail.com>
Link: https://lore.kernel.org/lkml/20240422133219.2710061-2-ria.freelander@gmail.com


Reviewed-by: default avatarAndy Shevchenko <andy@kernel.org>
Tested-by: default avatarHugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20241007162716.3122912-1-hugo@hugovil.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 0927c649

drivers/tty/serial/sc16is7xx.c

+1 −1
Original line number Diff line number Diff line
@@ -1473,7 +1473,7 @@ static int sc16is7xx_setup_mctrl_ports(struct sc16is7xx_port *s, 
}



static const struct serial_rs485 sc16is7xx_rs485_supported = {

	.flags = SER_RS485_ENABLED | SER_RS485_RTS_AFTER_SEND,

	.flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND,

	.delay_rts_before_send = 1,

	.delay_rts_after_send = 1,	/* Not supported but keep returning -EINVAL */

};