Re: [PATCH v2 1/4] dt-bindings: dma: Add binding for Actions Semi Owl SoCs
From: Vinod <vkoul@kernel.org>
Date: 2018-07-24 12:16:15
Also in:
dmaengine, linux-arm-kernel, lkml
Hi Mani, Patch title should be dmaengine: ... Please always use the apt tags and one can find them using git log <subsystem> On 23-07-18, 09:47, Manivannan Sadhasivam wrote:
Add devicetree binding for Actions Semi Owl SoCs DMA controller.
It would help for review to describe the controller here
quoted hunk ↗ jump to hunk
Signed-off-by: Manivannan Sadhasivam <redacted> --- .../devicetree/bindings/dma/owl-dma.txt | 46 +++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 Documentation/devicetree/bindings/dma/owl-dma.txtdiff --git a/Documentation/devicetree/bindings/dma/owl-dma.txt b/Documentation/devicetree/bindings/dma/owl-dma.txt new file mode 100644 index 000000000000..dd6ce237b216 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/owl-dma.txt@@ -0,0 +1,46 @@ +* Actions Semi Owl SoCs DMA controller + +This binding follows the generic DMA bindings defined in dma.txt. + +Required properties: +- compatible: Should be "actions,s900-dma". +- reg: Should contain DMA registers location and length. +- interrupts: Should contain 4 interrupts shared by all channel. +- #dma-cells: Must be <1>. Used to represent the number of integer + cells in the dmas property of client device. +- dma-channels: Physical channels supported. +- dma-requests: Virtual channels supported.
not really, virtual channel is a software concepts. On the other hand you may have request lines in hw and you can describe that, if not skip this one
+- clocks: Phandle and Specifier of the clock feeding the DMA controller.
+
+Example:
+
+Controller:
+ dma: dma-controller@e0260000 {
+ compatible = "actions,s900-dma";
+ reg = <0x0 0xe0260000 0x0 0x1000>;
+ interrupts = <GIC_SPI 57 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 58 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 59 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 60 IRQ_TYPE_LEVEL_HIGH>;
+ #dma-cells = <1>;
+ dma-channels = <12>;
+ dma-requests = <46>;
+ clocks = <&clock CLK_DMAC>;
+ };
+
+Client:
+
+DMA clients connected to the Actions Semi Owl SoCs DMA controller must
+use the format described in the dma.txt file, using a two-cell specifier
+for each channel.
+
+The two cells in order are:
+1. A phandle pointing to the DMA controller.
+2. The channel id.
+
+uart5: serial@e012a000 {
+ ...
+ dma-names = "tx", "rx";
+ dmas = <&dma 26>, <&dma 27>;
+ ...
+};
--
2.17.1-- ~Vinod