[PATCH v10 04/11] dmaengine: st_fdma: Add STMicroelectronics FDMA DT binding documentation

From: Peter Griffin
Date: Sat Oct 08 2016 - 08:53:49 EST


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@xxxxxx>
Signed-off-by: Peter Griffin <peter.griffin@xxxxxxxxxx>
Acked-by: Rob Herring <robh@xxxxxxxxxx>
---
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";
+ };
--
1.9.1