[alsa-devel] [PATCH 1/6] ASoC: davinci-mcbsp: add binding for McBSP

Petr Kulhavy petr at barix.com
Wed Apr 6 15:21:28 CEST 2016


Add devicetree binding for the TI DA8xx/OMAP-L1x/AM17xx/AM18xx
MultiChannel Buffered Serial Port (McBSP)

The optional register range "dat" is not implemented at the moment.
The current driver supports only DMA into RX/TX registers but no FIFO.
Once the FIFO is implemented in the driver the "dat" range will be used.

Signed-off-by: Petr Kulhavy <petr at barix.com>
---
 .../bindings/sound/davinci-mcbsp-audio.txt         | 57 ++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/sound/davinci-mcbsp-audio.txt

diff --git a/Documentation/devicetree/bindings/sound/davinci-mcbsp-audio.txt b/Documentation/devicetree/bindings/sound/davinci-mcbsp-audio.txt
new file mode 100644
index 000000000000..f60fceb927dd
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/davinci-mcbsp-audio.txt
@@ -0,0 +1,57 @@
+Texas Instruments DaVinci McBSP module
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+This binding describes the "Multi-channel Buffered Serial Port" (McBSP)
+audio interface found in some TI DaVinci processors like e.g. the DA850,
+DM6446, DA355.
+
+
+Required properties:
+~~~~~~~~~~~~~~~~~~~~
+- compatible : "ti,da850-mcbsp-audio"
+
+- reg : physical base address and length of the controller memory mapped
+        region(s).
+- reg-names : Should contain:
+         * "mpu" for the main registers (required). For compatibility with
+           existing software, it is recommended this is the first entry.
+         * "dat" for the data FIFO (optional).
+
+- dmas: two element list of DMA controller phandles and DMA request line
+        ordered pairs.
+- dma-names: identifier string for each DMA request line in the dmas property.
+	     These strings correspond 1:1 with the ordered pairs in dmas. The dma
+	     identifiers must be "rx" and "tx".
+
+Optional properties:
+~~~~~~~~~~~~~~~~~~~~
+- interrupts : Interrupt numbers for McBSP
+- interrupt-names : Known interrupt names are "rx" and "tx"
+
+- pinctrl-0: Should specify pin control group used for this controller.
+- pinctrl-names: Should contain only one value - "default", for more details
+  		 please refer to pinctrl-bindings.txt
+
+- channel-combine : boolean. If present L and R channels are combined into one
+		DMA transfer, however the labelling of the channels is swapped.
+		Therefore this option should be used only if the channels can
+		be swapped back at the codec side again.
+
+Example (AM1808):
+~~~~~~~~~~~~~~~~~
+
+mcbsp0: mcbsp at 1d10000 {
+	compatible = "ti,davinci-mcbsp-audio";
+	pinctrl-names = "default";
+	pinctrl-0 = <&mcbsp0_pins>;
+
+	reg = 	<0x00110000 0x1000>,
+		<0x00310000 0x1000>;
+	reg-names = "mpu", "dat";
+	interrupts = <97 98>;
+	interrupts-names = "rx", "tx";
+	dmas = <&edma0 3
+		&edma0 2>;
+	dma-names = "tx", "rx";
+	status = "okay";
+};
-- 
1.9.1



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