[PATCH] ARM: DTS: kirkwood-openrd: provide template for RS-232/485 configuration

Andrew Lunn andrew at lunn.ch
Sun Jan 24 09:28:21 PST 2016


On Sat, Jan 23, 2016 at 10:37:17PM +0200, Aaro Koskinen wrote:
> Some OpenRD boards have RS-232 and RS-486 connectors wired, but using them
> needs a custom DTB as the current DTB configures SD card slot instead.
> 
> This patch adds documentation into the DTS on how to change
> the configuration.
> 
> Signed-off-by: Aaro Koskinen <aaro.koskinen at iki.fi>

Reviewed-by: Andrew Lunn <andrew at lunn.ch>

Thanks
	Andrew

> ---
>  arch/arm/boot/dts/kirkwood-openrd.dtsi | 31 ++++++++++++++++++++++++++++++-
>  1 file changed, 30 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm/boot/dts/kirkwood-openrd.dtsi b/arch/arm/boot/dts/kirkwood-openrd.dtsi
> index f65b727..24f1d30 100644
> --- a/arch/arm/boot/dts/kirkwood-openrd.dtsi
> +++ b/arch/arm/boot/dts/kirkwood-openrd.dtsi
> @@ -40,7 +40,7 @@
>  			pinctrl-0 = <&pmx_select28 &pmx_sdio_cd &pmx_select34>;
>  			pinctrl-names = "default";
>  
> -			pmx_select28: pmx-select-rs232-rs484 {
> +			pmx_select28: pmx-select-rs232-rs485 {
>  				marvell,pins = "mpp28";
>  				marvell,function = "gpio";
>  			};
> @@ -65,10 +65,39 @@
>  			status = "okay";
>  			cd-gpios = <&gpio0 29 9>;
>  		};
> +		gpio at 10100 {
> +			p28 {
> +				gpio-hog;
> +				gpios = <28 GPIO_ACTIVE_HIGH>;
> +				/*
> +				 * SelRS232or485 selects between RS-232 or RS-485
> +				 * mode for the second UART.
> +				 *
> +				 * Low: RS-232
> +				 * High: RS-485
> +				 *
> +				 * To use the second UART, you need to change also
> +				 * the SelUARTorSD.
> +				 */
> +				output-low;
> +				line-name = "SelRS232or485";
> +			};
> +		};
>  		gpio at 10140 {
>  			p2 {
>  				gpio-hog;
>  				gpios = <2 GPIO_ACTIVE_HIGH>;
> +				/*
> +				 * SelUARTorSD selects between the second UART
> +				 * (serial at 12100) and SD (mvsdio at 90000).
> +				 *
> +				 * Low: UART
> +				 * High: SD
> +				 *
> +				 * When changing this line make sure the newly
> +				 * selected device node is enabled and the
> +				 * previously selected device node is disabled.
> +				 */
>  				output-high; /* Select SD by default */
>  				line-name = "SelUARTorSD";
>  			};
> -- 
> 2.4.0
> 



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