From 87c5cbf71ecbb9e289d60a2df22eb686c70bf196 Mon Sep 17 00:00:00 2001
From: Daniel Golle <daniel@makrotopia.org>
Date: Fri, 7 Feb 2020 11:53:35 +0200
Subject: [PATCH] serial: ar933x_uart: set UART_CS_{RX,TX}_READY_ORIDE
Git-commit: 87c5cbf71ecbb9e289d60a2df22eb686c70bf196
Patch-mainline: v5.6-rc3
References: git-fixes
On AR934x this UART is usually not initialized by the bootloader
as it is only used as a secondary serial port while the primary
UART is a newly introduced NS16550-compatible.
In order to make use of the ar933x-uart on AR934x without RTS/CTS
hardware flow control, one needs to set the
UART_CS_{RX,TX}_READY_ORIDE bits as other than on AR933x where this
UART is used as primary/console, the bootloader on AR934x typically
doesn't set those bits.
Setting them explicitely on AR933x should not do any harm, so just
set them unconditionally.
Tested-by: Chuanhong Guo <gch981213@gmail.com>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Link: https://lore.kernel.org/r/20200207095335.GA179836@makrotopia.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/tty/serial/ar933x_uart.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/tty/serial/ar933x_uart.c b/drivers/tty/serial/ar933x_uart.c
index 3bdd56a1021b..ea12f10610b6 100644
--- a/drivers/tty/serial/ar933x_uart.c
+++ b/drivers/tty/serial/ar933x_uart.c
@@ -286,6 +286,10 @@ static void ar933x_uart_set_termios(struct uart_port *port,
ar933x_uart_rmw_set(up, AR933X_UART_CS_REG,
AR933X_UART_CS_HOST_INT_EN);
+ /* enable RX and TX ready overide */
+ ar933x_uart_rmw_set(up, AR933X_UART_CS_REG,
+ AR933X_UART_CS_TX_READY_ORIDE | AR933X_UART_CS_RX_READY_ORIDE);
+
/* reenable the UART */
ar933x_uart_rmw(up, AR933X_UART_CS_REG,
AR933X_UART_CS_IF_MODE_M << AR933X_UART_CS_IF_MODE_S,
@@ -418,6 +422,10 @@ static int ar933x_uart_startup(struct uart_port *port)
ar933x_uart_rmw_set(up, AR933X_UART_CS_REG,
AR933X_UART_CS_HOST_INT_EN);
+ /* enable RX and TX ready overide */
+ ar933x_uart_rmw_set(up, AR933X_UART_CS_REG,
+ AR933X_UART_CS_TX_READY_ORIDE | AR933X_UART_CS_RX_READY_ORIDE);
+
/* Enable RX interrupts */
up->ier = AR933X_UART_INT_RX_VALID;
ar933x_uart_write(up, AR933X_UART_INT_EN_REG, up->ier);
--
2.26.2