This patch adds the DT binding documentation for the FDMA constroller found on STi based chipsets from STMicroelectronics.
Signed-off-by: Ludovic Barre ludovic.barre@st.com Signed-off-by: Peter Griffin peter.griffin@linaro.org Acked-by: Rob Herring robh@kernel.org --- Documentation/devicetree/bindings/dma/st_fdma.txt | 87 +++++++++++++++++++++++ 1 file changed, 87 insertions(+) create mode 100644 Documentation/devicetree/bindings/dma/st_fdma.txt
diff --git a/Documentation/devicetree/bindings/dma/st_fdma.txt b/Documentation/devicetree/bindings/dma/st_fdma.txt new file mode 100644 index 0000000..495d853 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/st_fdma.txt @@ -0,0 +1,87 @@ +* STMicroelectronics Flexible Direct Memory Access Device Tree bindings + +The FDMA is a general-purpose direct memory access controller capable of +supporting 16 independent DMA channels. It accepts up to 32 DMA requests. +The FDMA is based on a Slim processor which requires a firmware. + +* FDMA Controller + +Required properties: +- compatible : Should be one of + - st,stih407-fdma-mpe31-11, "st,slim-rproc"; + - st,stih407-fdma-mpe31-12, "st,slim-rproc"; + - st,stih407-fdma-mpe31-13, "st,slim-rproc"; +- reg : Should contain an entry for each name in reg-names +- reg-names : Must contain "slimcore", "dmem", "peripherals", "imem" entries +- interrupts : Should contain one interrupt shared by all channels +- dma-channels : Number of channels supported by the controller +- #dma-cells : Must be <3>. See DMA client section below +- clocks : Must contain an entry for each clock +See: Documentation/devicetree/bindings/clock/clock-bindings.txt + + +Example: + + fdma0: dma-controller@8e20000 { + compatible = "st,stih407-fdma-mpe31-11", "st,slim-rproc"; + reg = <0x8e20000 0x8000>, + <0x8e30000 0x3000>, + <0x8e37000 0x1000>, + <0x8e38000 0x8000>; + reg-names = "slimcore", "dmem", "peripherals", "imem"; + clocks = <&clk_s_c0_flexgen CLK_FDMA>, + <&clk_s_c0_flexgen CLK_EXT2F_A9>, + <&clk_s_c0_flexgen CLK_EXT2F_A9>, + <&clk_s_c0_flexgen CLK_EXT2F_A9>; + interrupts = <GIC_SPI 5 IRQ_TYPE_NONE>; + dma-channels = <16>; + #dma-cells = <3>; + }; + +* DMA client + +Required properties: +- dmas: Comma separated list of dma channel requests +- dma-names: Names of the aforementioned requested channels + +Each dmas request consists of 4 cells: +1. A phandle pointing to the FDMA controller +2. The request line number +3. A 32bit mask specifying (see include/linux/platform_data/dma-st-fdma.h) + -bit 2-0: Holdoff value, dreq will be masked for + 0x0: 0-0.5us + 0x1: 0.5-1us + 0x2: 1-1.5us + -bit 17: data swap + 0x0: disabled + 0x1: enabled + -bit 21: Increment Address + 0x0: no address increment between transfers + 0x1: increment address between transfers + -bit 22: 2 STBus Initiator Coprocessor interface + 0x0: high priority port + 0x1: low priority port +4. transfers type + 0 free running + 1 paced + +Example: + + sti_uni_player2: sti-uni-player@2 { + compatible = "st,sti-uni-player"; + status = "disabled"; + #sound-dai-cells = <0>; + st,syscfg = <&syscfg_core>; + clocks = <&clk_s_d0_flexgen CLK_PCM_2>; + assigned-clocks = <&clk_s_d0_flexgen CLK_PCM_2>; + assigned-clock-parents = <&clk_s_d0_quadfs 2>; + assigned-clock-rates = <50000000>; + reg = <0x8D82000 0x158>; + interrupts = <GIC_SPI 86 IRQ_TYPE_NONE>; + dmas = <&fdma0 4 0 1>; + dai-name = "Uni Player #1 (DAC)"; + dma-names = "tx"; + st,uniperiph-id = <2>; + st,version = <5>; + st,mode = "PCM"; + };