diff options
| author | Farouk Bouabid <farouk.bouabid@theobroma-systems.com> | 2024-02-08 18:39:56 +0300 |
|---|---|---|
| committer | Heiko Stuebner <heiko@sntech.de> | 2024-02-13 22:05:47 +0300 |
| commit | 5963d97aa780619ffb66cf4886c0ca1175ccbd3e (patch) | |
| tree | becb5306fdff82e5c9c6f84601b1a25dc353b03f | |
| parent | 54448f711aa32f176534bbd7b1903cc6d1c8a50d (diff) | |
| download | linux-5963d97aa780619ffb66cf4886c0ca1175ccbd3e.tar.xz | |
arm64: dts: rockchip: add rs485 support on uart5 of px30-ringneck-haikou
A hardware switch can set the rs485 transceiver into half or full duplex
mode.
Switching to the half-duplex mode requires the user to enable em485 on
uart5 using ioctl, DE/RE are both connected to GPIO0_B5 which is the
RTS signal for uart0. Implement GPIO0_B5 as rts-gpios with RTS_ON_SEND
option enabled (default) so that driver mode gets enabled while sending
(RTS high) and receiver mode gets enabled while not sending (RTS low).
In full-duplex mode (em485 is disabled), DE is connected to GPIO0_B5 and
RE is grounded (enabled). Since GPIO0_B5 is implemented as rts-gpios, the
driver mode gets enabled whenever we want to send something and RE is not
affected (always enabled) in this case by the state of RTS.
Signed-off-by: Farouk Bouabid <farouk.bouabid@theobroma-systems.com>
Link: https://lore.kernel.org/r/20240208-dev-rx-enable-v6-2-39e68e17a339@theobroma-systems.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
| -rw-r--r-- | arch/arm64/boot/dts/rockchip/px30-ringneck-haikou.dts | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/boot/dts/rockchip/px30-ringneck-haikou.dts b/arch/arm64/boot/dts/rockchip/px30-ringneck-haikou.dts index 16798eb77077..ae398acdcf45 100644 --- a/arch/arm64/boot/dts/rockchip/px30-ringneck-haikou.dts +++ b/arch/arm64/boot/dts/rockchip/px30-ringneck-haikou.dts @@ -227,6 +227,7 @@ &uart5 { pinctrl-0 = <&uart5_xfer>; + rts-gpios = <&gpio0 RK_PB5 GPIO_ACTIVE_HIGH>; status = "okay"; }; |