Commit 6300b140 authored by Andreas Abel's avatar Andreas Abel Committed by Greg Kroah-Hartman
Browse files

serial: tegra: add internal loopback functionality 



Add the internal loopback functionality that can be enabled with
TIOCM_LOOP.

Signed-off-by: default avatarAndreas Abel <aabel@nvidia.com>
Signed-off-by: default avatarKrishna Yarlagadda <kyarlagadda@nvidia.com>
Acked-by: default avatarThierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/1565609303-27000-2-git-send-email-kyarlagadda@nvidia.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent d2ace81b

drivers/tty/serial/serial-tegra.c

+22 −4
Original line number Diff line number Diff line
@@ -4,7 +4,7 @@ 
 *

 * High-speed serial driver for NVIDIA Tegra SoCs

 *

 * Copyright (c) 2012-2013, NVIDIA CORPORATION.  All rights reserved.

 * Copyright (c) 2012-2019, NVIDIA CORPORATION.  All rights reserved.

 *

 * Author: Laxman Dewangan <ldewangan@nvidia.com>

 */
@@ -192,16 +192,34 @@ static void set_dtr(struct tegra_uart_port *tup, bool active) 
	}

}



static void set_loopbk(struct tegra_uart_port *tup, bool active)

{

	unsigned long mcr = tup->mcr_shadow;



	if (active)

		mcr |= UART_MCR_LOOP;

	else

		mcr &= ~UART_MCR_LOOP;



	if (mcr != tup->mcr_shadow) {

		tegra_uart_write(tup, mcr, UART_MCR);

		tup->mcr_shadow = mcr;

	}

}



static void tegra_uart_set_mctrl(struct uart_port *u, unsigned int mctrl)

{

	struct tegra_uart_port *tup = to_tegra_uport(u);

	int dtr_enable;

	int enable;



	tup->rts_active = !!(mctrl & TIOCM_RTS);

	set_rts(tup, tup->rts_active);



	dtr_enable = !!(mctrl & TIOCM_DTR);

	set_dtr(tup, dtr_enable);

	enable = !!(mctrl & TIOCM_DTR);

	set_dtr(tup, enable);



	enable = !!(mctrl & TIOCM_LOOP);

	set_loopbk(tup, enable);

}



static void tegra_uart_break_ctl(struct uart_port *u, int break_ctl)

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