[PATCH 5.10 299/717] arm64: dts: rockchip: Fix UART pull-ups on rk3328

From: Greg Kroah-Hartman
Date: Mon Dec 28 2020 - 10:00:50 EST


From: Chen-Yu Tsai <wens@xxxxxxxx>

[ Upstream commit 94dad6bed3c86c00050bf7c2b2ad6b630facae31 ]

For UARTs, the local pull-ups should be on the RX pin, not the TX pin.
UARTs transmit active-low, so a disconnected RX pin should be pulled
high instead of left floating to prevent noise being interpreted as
transmissions.

This gets rid of bogus sysrq events when the UART console is not
connected.

Fixes: 52e02d377a72 ("arm64: dts: rockchip: add core dtsi file for RK3328 SoCs")
Signed-off-by: Chen-Yu Tsai <wens@xxxxxxxx>
Link: https://lore.kernel.org/r/20201204064805.6480-1-wens@xxxxxxxxxx
Signed-off-by: Heiko Stuebner <heiko@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm64/boot/dts/rockchip/rk3328.dtsi | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/arm64/boot/dts/rockchip/rk3328.dtsi b/arch/arm64/boot/dts/rockchip/rk3328.dtsi
index bbdb19a3e85d1..db0d5c8e5f96a 100644
--- a/arch/arm64/boot/dts/rockchip/rk3328.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3328.dtsi
@@ -1237,8 +1237,8 @@

uart0 {
uart0_xfer: uart0-xfer {
- rockchip,pins = <1 RK_PB1 1 &pcfg_pull_up>,
- <1 RK_PB0 1 &pcfg_pull_none>;
+ rockchip,pins = <1 RK_PB1 1 &pcfg_pull_none>,
+ <1 RK_PB0 1 &pcfg_pull_up>;
};

uart0_cts: uart0-cts {
@@ -1256,8 +1256,8 @@

uart1 {
uart1_xfer: uart1-xfer {
- rockchip,pins = <3 RK_PA4 4 &pcfg_pull_up>,
- <3 RK_PA6 4 &pcfg_pull_none>;
+ rockchip,pins = <3 RK_PA4 4 &pcfg_pull_none>,
+ <3 RK_PA6 4 &pcfg_pull_up>;
};

uart1_cts: uart1-cts {
@@ -1275,15 +1275,15 @@

uart2-0 {
uart2m0_xfer: uart2m0-xfer {
- rockchip,pins = <1 RK_PA0 2 &pcfg_pull_up>,
- <1 RK_PA1 2 &pcfg_pull_none>;
+ rockchip,pins = <1 RK_PA0 2 &pcfg_pull_none>,
+ <1 RK_PA1 2 &pcfg_pull_up>;
};
};

uart2-1 {
uart2m1_xfer: uart2m1-xfer {
- rockchip,pins = <2 RK_PA0 1 &pcfg_pull_up>,
- <2 RK_PA1 1 &pcfg_pull_none>;
+ rockchip,pins = <2 RK_PA0 1 &pcfg_pull_none>,
+ <2 RK_PA1 1 &pcfg_pull_up>;
};
};

--
2.27.0