Merge branch 'topic/iio' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into asoc-st-dfsdm

5 files changed, 209 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32
new file mode 100644
index 000000000000..da9822309f07
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32
@@ -0,0 +1,16 @@
+What:		/sys/bus/iio/devices/iio:deviceX/in_voltage_spi_clk_freq
+KernelVersion:	4.14
+Contact:	arnaud.pouliquen@st.com
+Description:
+		For audio purpose only.
+		Used by audio driver to set/get the spi input frequency.
+		This is mandatory if DFSDM is slave on SPI bus, to
+		provide information on the SPI clock frequency during runtime
+		Notice that the SPI frequency should be a multiple of sample
+		frequency to ensure the precision.
+		if DFSDM input is SPI master
+			Reading  SPI clkout frequency,
+			error on writing
+		If DFSDM input is SPI Slave:
+			Reading returns value previously set.
+			Writing value before starting conversions.
\ No newline at end of file
diff --git a/Documentation/devicetree/bindings/iio/adc/sigma-delta-modulator.txt b/Documentation/devicetree/bindings/iio/adc/sigma-delta-modulator.txt
new file mode 100644
index 000000000000..e9ebb8a20e0d
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/sigma-delta-modulator.txt
@@ -0,0 +1,13 @@
+Device-Tree bindings for sigma delta modulator
+
+Required properties:
+- compatible: should be "ads1201", "sd-modulator". "sd-modulator" can be use
+	as a generic SD modulator if modulator not specified in compatible list.
+- #io-channel-cells = <1>: See the IIO bindings section "IIO consumers".
+
+Example node:
+
+	ads1202: adc@0 {
+		compatible = "sd-modulator";
+		#io-channel-cells = <1>;
+	};
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@0 {
+		compatible = "ads1202";
+		#io-channel-cells = <1>;
+	};
+
+	dfsdm: dfsdm@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@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@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>;
+		};
+	}
diff --git a/Documentation/driver-api/iio/hw-consumer.rst b/Documentation/driver-api/iio/hw-consumer.rst
new file mode 100644
index 000000000000..8facce6a6733
--- /dev/null
+++ b/Documentation/driver-api/iio/hw-consumer.rst
@@ -0,0 +1,51 @@
+===========
+HW consumer
+===========
+An IIO device can be directly connected to another device in hardware. in this
+case the buffers between IIO provider and IIO consumer are handled by hardware.
+The Industrial I/O HW consumer offers a way to bond these IIO devices without
+software buffer for data. The implementation can be found under
+:file:`drivers/iio/buffer/hw-consumer.c`
+
+
+* struct :c:type:`iio_hw_consumer` — Hardware consumer structure
+* :c:func:`iio_hw_consumer_alloc` — Allocate IIO hardware consumer
+* :c:func:`iio_hw_consumer_free` — Free IIO hardware consumer
+* :c:func:`iio_hw_consumer_enable` — Enable IIO hardware consumer
+* :c:func:`iio_hw_consumer_disable` — Disable IIO hardware consumer
+
+
+HW consumer setup
+=================
+
+As standard IIO device the implementation is based on IIO provider/consumer.
+A typical IIO HW consumer setup looks like this::
+
+	static struct iio_hw_consumer *hwc;
+
+	static const struct iio_info adc_info = {
+		.read_raw = adc_read_raw,
+	};
+
+	static int adc_read_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *chan, int *val,
+				int *val2, long mask)
+	{
+		ret = iio_hw_consumer_enable(hwc);
+
+		/* Acquire data */
+
+		ret = iio_hw_consumer_disable(hwc);
+	}
+
+	static int adc_probe(struct platform_device *pdev)
+	{
+		hwc = devm_iio_hw_consumer_alloc(&iio->dev);
+	}
+
+More details
+============
+.. kernel-doc:: include/linux/iio/hw-consumer.h
+.. kernel-doc:: drivers/iio/buffer/industrialio-hw-consumer.c
+   :export:
+
diff --git a/Documentation/driver-api/iio/index.rst b/Documentation/driver-api/iio/index.rst
index e5c3922d1b6f..7fba341bd8b2 100644
--- a/Documentation/driver-api/iio/index.rst
+++ b/Documentation/driver-api/iio/index.rst
@@ -15,3 +15,4 @@ Contents:
    buffers
    triggers
    triggered-buffers
+   hw-consumer