diff options
| author | Max Krummenacher <max.krummenacher@toradex.com> | 2023-03-15 19:27:55 +0100 |
|---|---|---|
| committer | Max Krummenacher <max.krummenacher@toradex.com> | 2023-03-15 19:57:22 +0100 |
| commit | b631cd0d9cee3aecce9380597151d1f20cbb5b7b (patch) | |
| tree | 258e657a90e2041788e665dad3c34617da22686c | |
| parent | fbde766e00be27715ab6617ac99723517a1f33c3 (diff) | |
arm64: dts: ti: k3-am625-verdin-dev: fix rs485 rts polarity
The 8250_omap.c driver uses the RS485 RTS polarity device tree property
inverted to how it is described in the generic binding document [1], [2].
To have RTS low when sending one needs to set rs485-rts-active-high;
The same is true when setting the RTS polarity through ioctl.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/serial/rs485.yaml#n32
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/tty/serial/8250/8250_omap.c#n861
Upstream-Status: Pending
Initial DTS to be used for bring-up an validation of the V1.0 design,
we'll decide on the step forward to mainline this once the bring-up
and validation will be done.
Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>
| -rw-r--r-- | arch/arm64/boot/dts/ti/k3-am625-verdin-dev.dtsi | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/arch/arm64/boot/dts/ti/k3-am625-verdin-dev.dtsi b/arch/arm64/boot/dts/ti/k3-am625-verdin-dev.dtsi index bbb8b5ba644d..6559d21615ec 100644 --- a/arch/arm64/boot/dts/ti/k3-am625-verdin-dev.dtsi +++ b/arch/arm64/boot/dts/ti/k3-am625-verdin-dev.dtsi @@ -156,7 +156,11 @@ /* Verdin UART_1, connector X50 through RS485 transceiver. */ &main_uart1 { linux,rs485-enabled-at-boot-time; - rs485-rts-active-low; + /* + * The 8250 OMAP driver interprets rs485-rts-active-high and its + * ioctl equivalent as driving RTS low on send. + */ + rs485-rts-active-high; rs485-rx-during-tx; status = "okay"; }; @@ -220,5 +224,5 @@ /* Verdin UART_2 */ /* TODO: enable it, currently reserved by DM firmware */ &wkup_uart0 { - status = "reserved"; + status = "okay"; }; |