[PATCH v5 2/2] dt-bindings: iio: dac: Add docs for AD5758 DAC

Stefan Popa
2018-07-04T14:32:53Z

Signed-off-by: Stefan Popa <stefan.popa@analog.com>
---
Changes in v5:
- used a dac@0 as a more generic node name instead of ad5758@0.
Changes in v4:
- Nothing changed, just to follow the patch set version.
Changes in v3:
- AD5758 can be both a current and voltage output DAC. The
decision is made based on the DT and the channel type is set
during probe.
- range was replaced by range-microvolt and range-microamp
- dc-dc-mode, range-microvolt and range-microamp are required
properties.
- Introduced a slew-time-us property from which slew rate clock
and slew rate step are calculated using a best match algorithm.
- Added units in the name of the properties.
- Offered more explanation for the various modes of operation.

Changes in v2:
- Nothing changed, just to follow the patch set version.

.../devicetree/bindings/iio/dac/ad5758.txt | 73 ++++++++++++++++++++++
MAINTAINERS | 1 +
2 files changed, 74 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/dac/ad5758.txt

diff --git a/Documentation/devicetree/bindings/iio/dac/ad5758.txt b/Documentation/devicetree/bindings/iio/dac/ad5758.txt
new file mode 100644
index 0000000..90bc496
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/dac/ad5758.txt
@@ -0,0 +1,73 @@
+Analog Devices AD5758 DAC device driver
+
+Required properties for the AD5758:
+ - compatible: Must be "adi,ad5758"
+ - reg: SPI chip select number for the device
+ - spi-max-frequency: Max SPI frequency to use (< 50000000)
+ - spi-cpha: is the only mode that is supported
+
+Required properties:
+
+ - adi,dc-dc-mode: Mode of operation of the dc-to-dc converter
+ Dynamic Power Control (DPC)
+ In this mode, the AD5758 circuitry senses the output voltage and
+ dynamically regulates the supply voltage, VDPC+, to meet compliance
+ requirements plus an optimized headroom voltage for the output buffer.
+
+ Programmable Power Control (PPC)
+ In this mode, the VDPC+ voltage is user-programmable to a fixed level
+ that needs to accommodate the maximum output load required.
+
+ The output of the DAC core is either converted to a current or voltage
+ output at the VIOUT pin. Only one mode can be enabled at any one time.
+
+ The following values are currently supported:
+ * 1: DPC current mode
+ * 2: DPC voltage mode
+ * 3: PPC current mode
+
+ Depending on the selected output mode (voltage or current) one of the two properties must
+ be present:
+
+ - adi,range-microvolt: Voltage output range
+ The array of voltage output ranges must contain two fields:
+ * <0 5000000>: 0 V to 5 V voltage range
+ * <0 10000000>: 0 V to 10 V voltage range
+ * <(-5000000) 5000000>: ±5 V voltage range
+ * <(-10000000) 10000000>: ±10 V voltage range
+ - adi,range-microamp: Current output range
+ The array of current output ranges must contain two fields:
+ * <0 20000>: 0 mA to 20 mA current range
+ * <0 24000>: 0 mA to 24 mA current range
+ * <4 24000>: 4 mA to 20 mA current range
+ * <(-20000) 20000>: ±20 mA current range
+ * <(-24000) 24000>: ±24 mA current range
+ * <(-1000) 22000>: −1 mA to +22 mA current range
+
+Optional properties:
+
+ - adi,dc-dc-ilim-microamp: The dc-to-dc converter current limit
+ The following values are currently supported [uA]:
+ * 150000
+ * 200000
+ * 250000
+ * 300000
+ * 350000
+ * 400000
+
+ - adi,slew-time-us: The time it takes for the output to reach the full scale [uS]
+ The supported range is between 133us up to 1023984375us
+
+AD5758 Example:
+
+ dac@0 {
+ compatible = "adi,ad5758";
+ reg = <0>;
+ spi-max-frequency = <1000000>;
+ spi-cpha;
+
+ adi,dc-dc-mode = <2>;
+ adi,range-microvolt = <0 10000000>;
+ adi,dc-dc-ilim-microamp = <200000>;
+ adi,slew-time-us = <125000>;
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index 12d102d..60b1028 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -802,6 +802,7 @@ L: linux-iio@vger.kernel.org
W: http://ez.analog.com/community/linux-device-drivers
S: Supported
F: drivers/iio/dac/ad5758.c
+F: Documentation/devicetree/bindings/iio/dac/ad5758.txt

ANALOG DEVICES INC AD5686 DRIVER
M: Stefan Popa <stefan.popa@analog.com>
--
2.7.4