mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-16 15:46:41 +07:00
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@st.com> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
parent
8a5f0b6f6c
commit
6c82f947fc
128
Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.txt
Normal file
128
Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.txt
Normal file
@ -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>;
|
||||
};
|
||||
}
|
Loading…
Reference in New Issue
Block a user