[PATCH v3 1/3] dt-bindings: iio: health: add maxim,max86150

[Md Shofiqul Islam <shofiqtest@gmail.com>]

Add YAML binding schema for the Maxim MAX86150 combined ECG and PPG
biosensor.  The device exposes two PPG optical channels (Red and IR LED)
for heart rate and SpO2 measurement, and one ECG biopotential channel, all
accessible over I2C at up to 400 kHz.

An optional active-low interrupt line connects to the 32-entry hardware
FIFO almost-full output.  Two optional regulator supplies (vdd for the
digital core and leds for the LED anodes) cover boards that require
explicit power sequencing.

Signed-off-by: Md Shofiqul Islam <shofiqtest@gmail.com>
---
 .../bindings/iio/health/maxim,max86150.yaml   | 67 +++++++++++++++++++
 1 file changed, 67 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/health/maxim,max86150.yaml

diff --git a/Documentation/devicetree/bindings/iio/health/maxim,max86150.yaml b/Documentation/devicetree/bindings/iio/health/maxim,max86150.yaml
new file mode 100644
index 000000000000..1bf10fd1a3d2
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/health/maxim,max86150.yaml
@@ -0,0 +1,67 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/health/maxim,max86150.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Maxim MAX86150 ECG and PPG Biosensor
+
+maintainers:
+  - Md Shofiqul Islam <shofiqtest@gmail.com>
+
+description: |
+  The MAX86150 is an integrated biosensor SoC that combines:
+    - Two PPG (photoplethysmography) channels: Red LED and IR LED,
+      for heart rate and blood-oxygen saturation (SpO2) measurement.
+    - One ECG (electrocardiogram) channel for biopotential recording.
+
+  The device communicates over I2C at up to 400 kHz and raises an
+  active-low interrupt when the 32-entry hardware FIFO reaches its
+  configurable almost-full threshold.
+
+  Datasheet:
+    https://www.analog.com/media/en/technical-documentation/data-sheets/MAX86150.pdf
+
+properties:
+  compatible:
+    const: maxim,max86150
+
+  reg:
+    maxItems: 1
+    description: I2C device address, always 0x5E.
+
+  interrupts:
+    maxItems: 1
+    description: |
+      Active-low interrupt line.  Asserted when the FIFO almost-full
+      threshold is reached or when a new PPG sample is ready.
+
+  vdd-supply:
+    description: Digital core supply, 1.71 V to 1.89 V.
+
+  leds-supply:
+    description: LED anode supply, 3.0 V to 5.5 V.
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        biosensor@5e {
+            compatible = "maxim,max86150";
+            reg = <0x5e>;
+            interrupt-parent = <&gpio1>;
+            interrupts = <5 IRQ_TYPE_EDGE_FALLING>;
+            vdd-supply = <&vdd_1v8>;
+            leds-supply = <&vdd_3v3>;
+        };
+    };
-- 
2.51.1