From: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> Document the device-tree bindings of the "ad7192" driver. Added datasheet references for supported devices, explanation for each property supported by the driver, and an example. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> --- .../staging/iio/Documentation/adc/adi,ad7192.txt | 71 ++++++++++++++++++++++ 1 file changed, 71 insertions(+) create mode 100644 drivers/staging/iio/Documentation/adc/adi,ad7192.txt diff --git a/drivers/staging/iio/Documentation/adc/adi,ad7192.txt b/drivers/staging/iio/Documentation/adc/adi,ad7192.txt new file mode 100644 index 000000000000..1f8f769a003f --- /dev/null +++ b/drivers/staging/iio/Documentation/adc/adi,ad7192.txt @@ -0,0 +1,71 @@ +Analog Devices AD719x ADC Driver + +Reference: +[1] http://www.analog.com/en/products/analog-to-digital-converters/ad7190.html +[2] http://www.analog.com/en/products/analog-to-digital-converters/ad7192.html +[3] http://www.analog.com/en/products/analog-to-digital-converters/ad7193.html +[4] http://www.analog.com/en/products/analog-to-digital-converters/ad7195.html + +Required properties: + - compatible: Should be "adi,ad7190", "adi,ad7192", "adi,ad7193" + or "adi,ad7195" + - reg: SPI chip select number for the device + - spi-cpol, spi-cpha: Controller support only mode 3, so both spi-cpol + and spi-cpha should be present + - spi-max-frequency: Definition as per + see: Documentation/devicetree/bindings/spi/spi-bus.txt + - interrupt-parent: phandle to the parent interrupt controller + see: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt + - interrupts: IRQ line for the ADC + see: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt + +Recommended properties: + - adi,clock-source-select: sets the clock source to be used; values are + * 0 - external crystal, connected from pin MCLK1 to MCLK2 + * 1 - external clock, applied to MCLK2 pin + * 2 - internal 4.92 Mhz clock; pin MCLK2 is tristated (default) + * 3 - internal 4.92 Mhz clock; internal clock is available on MCLK2 + - adi,external-clock-Hz: if "adi,clock-source-select" is value '1', + this value should be specified to the ADC + - avdd-supply: Analog Supply Voltage, 4.75V to 5.25V. AVDD is + independent of DVDD + - dvdd-supply: Digital Supply Voltage, 2.7V to 5.25V. DVDD + is independent of AVDD + +Optional properties: + - adi,refin2-pins-enable: select external reference to be applied + to P1,REFIN2(+) & P0,REFIN2(-) pins instead of REFIN1(+) & REFIN1(-); + not available for "ad7195" + - adi,rejection-60-Hz-enable: enables simultaneous 50/60 Hz rejection + - adi,chop-enable: enable chop to minimize ADC offset and offset drift + - adi,buffer-enable: enables the buffer on the analog inputs + - adi,burnout-currents-enable: when selected, the 500 nA current sources + in the signal path are enabled; can be enabled only when buffer is active + and chop is disabled + - adi,sinc3-filter-enable: enables the SINC3 filter; if unset + the SINC4 digital filter is used after the modulator + - adi,unipolar-enable: when this is set voltage ranges must be unipolar + (e.g 0 to 5V) versus bipolar voltage ranges (e.g. -5V to 5V) + +Example: +ad7190@0 { + compatible = "adi,ad7190"; + reg = <0>; + spi-max-frequency = <1000000>; + spi-cpol; + spi-cpha; + + #interrupt-cells = <2>; + interrupts = <25 0x2>; + interrupt-parent = <&gpio>; + avdd-supply = <&adc_avdd>; + + adi,clock-source-select = /bits/ 8 <0>; + + adi,refin2-pins-enable; + adi,rejection-60-Hz-enable; + adi,buffer-enable; + adi,burnout-currents-enable; + adi,sinc3-filter-enable; + adi,unipolar-enable; +}; -- 2.14.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
