[alsa-devel] Applied "IIO: add DT bindings for stm32 DFSDM filter" to the asoc tree

Mark Brown broonie at kernel.org
Wed Jan 10 12:13:09 CET 2018


The patch

   IIO: add DT bindings for stm32 DFSDM filter

has been applied to the asoc tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

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to this mail.

Thanks,
Mark

>From 6c82f947fc9784b774cad0b90c20a5d703f9b763 Mon Sep 17 00:00:00 2001
From: Arnaud Pouliquen <arnaud.pouliquen at st.com>
Date: Wed, 10 Jan 2018 11:13:09 +0100
Subject: [PATCH] IIO: add DT bindings for stm32 DFSDM filter

Add bindings that describes STM32 Digital Filter for Sigma Delta
Modulators. DFSDM allows to connect sigma delta
modulators.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen at st.com>
Acked-by: Rob Herring <robh at kernel.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron at huawei.com>
Signed-off-by: Mark Brown <broonie at kernel.org>
---
 .../bindings/iio/adc/st,stm32-dfsdm-adc.txt        | 128 +++++++++++++++++++++
 1 file changed, 128 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.txt

diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.txt b/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.txt
new file mode 100644
index 000000000000..911492da48f3
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.txt
@@ -0,0 +1,128 @@
+STMicroelectronics STM32 DFSDM ADC device driver
+
+
+STM32 DFSDM ADC is a sigma delta analog-to-digital converter dedicated to
+interface external sigma delta modulators to STM32 micro controllers.
+It is mainly targeted for:
+- Sigma delta modulators (motor control, metering...)
+- PDM microphones (audio digital microphone)
+
+It features up to 8 serial digital interfaces (SPI or Manchester) and
+up to 4 filters on stm32h7.
+
+Each child node match with a filter instance.
+
+Contents of a STM32 DFSDM root node:
+------------------------------------
+Required properties:
+- compatible: Should be "st,stm32h7-dfsdm".
+- reg: Offset and length of the DFSDM block register set.
+- clocks: IP and serial interfaces clocking. Should be set according
+		to rcc clock ID and "clock-names".
+- clock-names: Input clock name "dfsdm" must be defined,
+		"audio" is optional. If defined CLKOUT is based on the audio
+		clock, else "dfsdm" is used.
+- #interrupt-cells = <1>;
+- #address-cells = <1>;
+- #size-cells = <0>;
+
+Optional properties:
+- spi-max-frequency: Requested only for SPI master mode.
+		  SPI clock OUT frequency (Hz). This clock must be set according
+		  to "clock" property. Frequency must be a multiple of the rcc
+		  clock frequency. If not, SPI CLKOUT frequency will not be
+		  accurate.
+
+Contents of a STM32 DFSDM child nodes:
+--------------------------------------
+
+Required properties:
+- compatible: Must be:
+	"st,stm32-dfsdm-adc" for sigma delta ADCs
+	"st,stm32-dfsdm-dmic" for audio digital microphone.
+- reg: Specifies the DFSDM filter instance used.
+- interrupts: IRQ lines connected to each DFSDM filter instance.
+- st,adc-channels:	List of single-ended channels muxed for this ADC.
+			valid values:
+				"st,stm32h7-dfsdm" compatibility: 0 to 7.
+- st,adc-channel-names:	List of single-ended channel names.
+- st,filter-order:  SinC filter order from 0 to 5.
+			0: FastSinC
+			[1-5]: order 1 to 5.
+			For audio purpose it is recommended to use order 3 to 5.
+- #io-channel-cells = <1>: See the IIO bindings section "IIO consumers".
+
+Required properties for "st,stm32-dfsdm-adc" compatibility:
+- io-channels: From common IIO binding. Used to pipe external sigma delta
+		modulator or internal ADC output to DFSDM channel.
+		This is not required for "st,stm32-dfsdm-pdm" compatibility as
+		PDM microphone is binded in Audio DT node.
+
+Required properties for "st,stm32-dfsdm-pdm" compatibility:
+- #sound-dai-cells: Must be set to 0.
+- dma: DMA controller phandle and DMA request line associated to the
+		filter instance (specified by the field "reg")
+- dma-names: Must be "rx"
+
+Optional properties:
+- st,adc-channel-types:	Single-ended channel input type.
+			- "SPI_R": SPI with data on rising edge (default)
+			- "SPI_F": SPI with data on falling edge
+			- "MANCH_R": manchester codec, rising edge = logic 0
+			- "MANCH_F": manchester codec, falling edge = logic 1
+- st,adc-channel-clk-src: Conversion clock source.
+			  - "CLKIN": external SPI clock (CLKIN x)
+			  - "CLKOUT": internal SPI clock (CLKOUT) (default)
+			  - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
+			  - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
+
+- st,adc-alt-channel: Must be defined if two sigma delta modulator are
+			  connected on same SPI input.
+			  If not set, channel n is connected to SPI input n.
+			  If set, channel n is connected to SPI input n + 1.
+
+- st,filter0-sync: Set to 1 to synchronize with DFSDM filter instance 0.
+		   Used for multi microphones synchronization.
+
+Example of a sigma delta adc connected on DFSDM SPI port 0
+and a pdm microphone connected on DFSDM SPI port 1:
+
+	ads1202: simple_sd_adc at 0 {
+		compatible = "ads1202";
+		#io-channel-cells = <1>;
+	};
+
+	dfsdm: dfsdm at 40017000 {
+		compatible = "st,stm32h7-dfsdm";
+		reg = <0x40017000 0x400>;
+		clocks = <&rcc DFSDM1_CK>;
+		clock-names = "dfsdm";
+		#interrupt-cells = <1>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		dfsdm_adc0: filter at 0 {
+			compatible = "st,stm32-dfsdm-adc";
+			#io-channel-cells = <1>;
+			reg = <0>;
+			interrupts = <110>;
+			st,adc-channels = <0>;
+			st,adc-channel-names = "sd_adc0";
+			st,adc-channel-types = "SPI_F";
+			st,adc-channel-clk-src = "CLKOUT";
+			io-channels = <&ads1202 0>;
+			st,filter-order = <3>;
+		};
+		dfsdm_pdm1: filter at 1 {
+			compatible = "st,stm32-dfsdm-dmic";
+			reg = <1>;
+			interrupts = <111>;
+			dmas = <&dmamux1 102 0x400 0x00>;
+			dma-names = "rx";
+			st,adc-channels = <1>;
+			st,adc-channel-names = "dmic1";
+			st,adc-channel-types = "SPI_R";
+			st,adc-channel-clk-src = "CLKOUT";
+			st,filter-order = <5>;
+		};
+	}
-- 
2.15.1



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