There have been several attempts to set the dma-names property on the SoC level (in rk356x.dtsi), but that appears to cause problems when set on channels without flow control. Quoting part of a previous attempt for clarification: > Nah, enabling it for bluetooth is fine because you have flow control. > My issues have been on channels without flow control. Without DMA it > simply drops messages or the channel hangs until you close and reopen > it. With DMA, when an overflow locks up the channel it is usually > unavailable until the board is rebooted. Setting it on the board level for the bluetooth connection was deemed safe, so do so for the Quartz64 Model B. This fixes the following error/warning: of_dma_request_slave_channel: dma-names property of node '/serial@fe650000' missing or empty dw-apb-uart fe650000.serial: failed to request DMA Signed-off-by: Diederik de Haas <didi.debian@xxxxxxxxx> Link: https://libera.irclog.whitequark.org/armlinux/2024-02-29 Link: https://lore.kernel.org/linux-rockchip/18284546.sWSEgdgrri@diego/ --- arch/arm64/boot/dts/rockchip/rk3566-quartz64-b.dts | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/boot/dts/rockchip/rk3566-quartz64-b.dts b/arch/arm64/boot/dts/rockchip/rk3566-quartz64-b.dts index b908ce006c26..13e599a85eb8 100644 --- a/arch/arm64/boot/dts/rockchip/rk3566-quartz64-b.dts +++ b/arch/arm64/boot/dts/rockchip/rk3566-quartz64-b.dts @@ -652,6 +652,7 @@ &tsadc { }; &uart1 { + dma-names = "tx", "rx"; pinctrl-names = "default"; pinctrl-0 = <&uart1m0_xfer &uart1m0_ctsn &uart1m0_rtsn>; status = "okay"; -- 2.45.2