dt-bindings: iio: flow: add Sensirion SLF3S liquid flow sensor

Document the bindings for the Sensirion SLF3S family of digital
liquid-flow sensors on I2C.  The family currently covers the
SLF3S-0600F, SLF3S-1300F and SLF3S-4000B variants.

All variants share the same register map and differ only in the flow
scale factor and the calibrated measurement range, which the driver
reads back from the product-information register.  Since that lookup
is needed in any case, a fallback compatible would buy nothing, so
each variant gets its own compatible without a fallback.  A future
drop-in compatible part can then claim one of these compatibles and
work on kernels that do not know its product ID yet.

The active calibration medium (water / IPA) is runtime-switchable
via the in_volumeflow_medium sysfs attribute and therefore not a
DT property.

Signed-off-by: Wadim Mueller <wafgo01@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>

Documentation/devicetree/bindings/iio/flow/sensirion,slf3s.yaml

@@ -0,0 +1,55 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/flow/sensirion,slf3s.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Sensirion SLF3S liquid flow sensor
+
+maintainers:
+  - Wadim Mueller <wafgo01@gmail.com>
+
+description:
+  Family of digital liquid-flow sensors from Sensirion with I2C interface. All
+  family members share the same register map; sub-types differ only in the flow
+  scale factor and the calibrated measurement range. The sub-type can be
+  identified from the product-information register.
+
+properties:
+  compatible:
+    enum:
+      - sensirion,slf3s-0600f
+      - sensirion,slf3s-1300f
+      - sensirion,slf3s-4000b
+
+  reg:
+    maxItems: 1
+
+  vdd-supply: true
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - vdd-supply
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        flow-sensor@8 {
+            compatible = "sensirion,slf3s-0600f";
+            reg = <0x08>;
+            vdd-supply = <&reg_3v3>;
+            interrupt-parent = <&gpio0>;
+            interrupts = <0 IRQ_TYPE_EDGE_RISING>;
+        };
+    };

MAINTAINERS

@@ -24591,6 +24591,13 @@ S:	Maintained
 F:	Documentation/ABI/testing/sysfs-bus-iio-chemical-sgp40
 F:	drivers/iio/chemical/sgp40.c
 
+SENSIRION SLF3S LIQUID FLOW SENSOR DRIVER
+M:	Wadim Mueller <wafgo01@gmail.com>
+R:	Maxwell Doose <maxwell@maxwelld.cc>
+L:	linux-iio@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/iio/flow/sensirion,slf3s.yaml
+
 SENSIRION SPS30 AIR POLLUTION SENSOR DRIVER
 M:	Tomasz Duszynski <tduszyns@gmail.com>
 S:	Maintained