Re: [PATCH v3 1/3] dt-bindings: iio: health: add maxim,max86150
From: Conor Dooley <conor@kernel.org>
Date: 2026-06-23 17:53:31
Also in:
linux-iio
On Tue, Jun 23, 2026 at 07:43:07PM +0300, Md Shofiqul Islam wrote:
quoted hunk ↗ jump to hunk
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 <redacted> --- .../bindings/iio/health/maxim,max86150.yaml | 67 +++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/health/maxim,max86150.yamldiff --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
ADI would like the prefix for newly added former maxim products to be "adi,".
+ + 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.
This is a 1.8v supply, the tolerances on it don't need to be mentioned here.
+ leds-supply: + description: LED anode supply, 3.0 V to 5.5 V.
Datasheet cites 5v as the max for this, not 5.5v, with a typical value of 3.3v. Makes me think that 3.3 is the intended value, since using a 5v supply could easily fluctuate over the maximum rated value. Looks like there's more supplies than this? I see: Vdd_ana Vdd_dig Vref Vled Additionally, these supplies should be mandatory. pw-bot: changes-requested
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ biosensor@5e {Seems to be prior art for calling things like this "heart-rate", although that is somewhat limited compared to what this device can do. Cheers, Conor.
+ 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
Attachments
- signature.asc [application/pgp-signature] 228 bytes