Re: [PATCH 08/10] arm64: dts: add description for solidrun imx8mp hummingboard-iiot

[Alexander Dahl <ada@thorsis.com>]

Hello Josua,

Am Tue, Oct 28, 2025 at 12:24:36PM +0000 schrieb Josua Mayer:
> Am 27.10.25 um 18:48 schrieb Josua Mayer:
> 
> > Add description for the SolidRun i.MX8MP HummingBoard IIoT.
> > The board is a new design around the i.MX8MP System on Module, not
> > sharing much with previous HummingBoards.
> >
> > It comes with some common features:
> > - 3x USB-3.0 Type A connector
> > - 2x 1Gbps RJ45 Ethernet
> > - USB Type-C Console Port
> > - microSD connector
> > - RTC with backup battery
> > - RGB Status LED
> > - 1x M.2 M-Key connector with PCI-E Gen. 3 x1
> > - 1x M.2 B-Key connector with USB-2.0/3.0 + SIM card holder
> > - 1x LVDS Display Connector
> > - 1x DSI Display Connector
> > - GPIO header
> > - 2x RS232/RS485 ports (configurable)
> > - 2x CAN
> >
> > In addition there is a board-to-board expansion connector to support
> > custom daughter boards with access to SPI, a range of GPIOs and -
> > notably - CAN and UART. Both 2x CAN and 2x UART can be muxed either
> > to this b2b connector, or a termianl block connector on the base board.
> >
> > The routing choice for UART and CAN is expressed through gpio
> > mux-controllers in DT and can be changed by applying dtb addons.
> >
> > Four dtb addons are provided:
> >
> > - dsi panel Winstar WJ70N3TYJHMNG0
> > - lvds panel Winstar WF70A8SYJHLNGA
> > - RS485 on UART port "A" (default rs232)
> > - RS485 on UART port "B" (default rs232)
> >
> > Signed-off-by: Josua Mayer <josua@solid-run.com>
> > ---
> >  arch/arm64/boot/dts/freescale/Makefile             |   6 +
> >  ...hummingboard-iiot-panel-dsi-WJ70N3TYJHMNG0.dtso |  70 ++
> >  ...ummingboard-iiot-panel-lvds-WF70A8SYJHLNGA.dtso | 105 +++
> >  .../imx8mp-hummingboard-iiot-rs485-a.dtso          |  18 +
> >  .../imx8mp-hummingboard-iiot-rs485-b.dtso          |  18 +
> >  .../dts/freescale/imx8mp-hummingboard-iiot.dts     | 710 +++++++++++++++++++++
> >  6 files changed, 927 insertions(+)
> cut
> > diff --git a/arch/arm64/boot/dts/freescale/imx8mp-hummingboard-iiot.dts b/arch/arm64/boot/dts/freescale/imx8mp-hummingboard-iiot.dts
> > new file mode 100644
> > index 0000000000000..2e4cb676bc9da
> > --- /dev/null
> > +++ b/arch/arm64/boot/dts/freescale/imx8mp-hummingboard-iiot.dts
> cut
> > +	led-controller@30 {
> > +		compatible = "ti,lp5562";
> > +		reg = <0x30>;
> > +		/* use internal clock, could use external generated by rtc */
> > +		clock-mode = /bits/ 8 <1>;
> > +		#address-cells = <1>;
> > +		#size-cells = <0>;
> > +
> > +		multi-led@0 {
> > +			reg = <0x0>;
> > +			color = <LED_COLOR_ID_RGB>;
> > +			#address-cells = <1>;
> > +			#size-cells = <0>;
> > +
> > +			led@0 {
> > +				reg = <0x0>;
> > +				color = <LED_COLOR_ID_RED>;
> > +				led-cur = /bits/ 8 <0x32>;
> > +				max-cur = /bits/ 8 <0x64>;
> > +			};
> > +
> > +			led@1 {
> > +				reg = <0x1>;
> > +				color = <LED_COLOR_ID_GREEN>;
> > +				led-cur = /bits/ 8 <0x19>;
> > +				max-cur = /bits/ 8 <0x32>;
> > +			};
> > +
> > +			led@2 {
> > +				reg = <0x2>;
> > +				color = <LED_COLOR_ID_BLUE>;
> > +				led-cur = /bits/ 8 <0x19>;
> > +				max-cur = /bits/ 8 <0x32>;
> > +			};
> > +		};
> > +
> > +		led@3 {
> > +			reg = <3>;
> > +			chan-name = "D8";
> 
> chan-name gives the led the name D6 in sysfs.
> 
> The bindings do not allow however setting chan-name on
> the multi-led, and it has an auto-generated name in sysfs.
> 
> Am I missing something? Can multi-leds have a custom name?

The sysfs names are auto-generated based on the attributes "color",
"function", and "label" with the last being discouraged for new
designs.  If the "ti,lp5562" driver does nothing special, you could
add "function" to the multi-led node and see if that fits your needs.

Adding linux-leds to Cc, because this is a LED related question.

Greets
Alex

> In v6.6 leds-lp5562 driver if I set in each multi-led led@[0-2] sub-node
> chan-name to the same string "D7" - then the sysfs name becomes D7.
> 
> > +			color = <LED_COLOR_ID_GREEN>;
> > +			led-cur = /bits/ 8 <0x19>;
> > +			max-cur = /bits/ 8 <0x64>;
> > +		};
> > +	};