[PATCH v2 12/12] dt-bindings: thermal: cooling-devices: Update support for 3 cells cooling device

[PATCH v2 12/12] dt-bindings: thermal: cooling-devices: Update support for 3 cells cooling device

[Daniel Lezcano]

From: Gaurav Kohli <gaurav.kohli@oss.qualcomm.com>

Extend the thermal cooling device binding to support a 3 cells specifier
along with the 2 cells format.

Update #cooling-cells property to enum to support both 2 and 3 arguments.

Fix pwm-fan.yaml to restrict the number of cells to 'const: 2'

Signed-off-by: Gaurav Kohli <gaurav.kohli@oss.qualcomm.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@oss.qualcomm.com>
---
 Documentation/devicetree/bindings/hwmon/pwm-fan.yaml      | 3 ++-
 .../bindings/thermal/thermal-cooling-devices.yaml         | 8 ++++++--
 .../devicetree/bindings/thermal/thermal-zones.yaml        | 3 ++-
 3 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/hwmon/pwm-fan.yaml b/Documentation/devicetree/bindings/hwmon/pwm-fan.yaml
index a84cc3a4cfdc..6a24851fd80d 100644
--- a/Documentation/devicetree/bindings/hwmon/pwm-fan.yaml
+++ b/Documentation/devicetree/bindings/hwmon/pwm-fan.yaml
@@ -63,7 +63,8 @@ properties:
     description: The PWM that is used to control the fan.
     maxItems: 1
 
-  "#cooling-cells": true
+  "#cooling-cells":
+    const: 2
 
 required:
   - compatible
diff --git a/Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml b/Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml
index b9022f1613d8..28f5818f1e60 100644
--- a/Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml
+++ b/Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml
@@ -44,10 +44,14 @@ select: true
 properties:
   "#cooling-cells":
     description:
-      Must be 2, in order to specify minimum and maximum cooling state used in
+      Must be 2 or 3. If 2, specifies minimum and maximum cooling state used in
       the cooling-maps reference. The first cell is the minimum cooling state
       and the second cell is the maximum cooling state requested.
-    const: 2
+      If 3, the first cell specifies the thermal mitigation device specifier
+      index for devices that support multiple thermal mitigation mechanisms.
+      The two other cells are respectively the minimum cooling state and the
+      maximum cooling state.
+    enum: [2, 3]
 
 additionalProperties: true
 
diff --git a/Documentation/devicetree/bindings/thermal/thermal-zones.yaml b/Documentation/devicetree/bindings/thermal/thermal-zones.yaml
index 0de0a9757ccc..1261ba0e802e 100644
--- a/Documentation/devicetree/bindings/thermal/thermal-zones.yaml
+++ b/Documentation/devicetree/bindings/thermal/thermal-zones.yaml
@@ -214,7 +214,8 @@ patternProperties:
                   device. Using the THERMAL_NO_LIMIT (-1UL) constant in the
                   cooling-device phandle limit specifier lets the framework
                   use the minimum and maximum cooling state for that cooling
-                  device automatically.
+                  device automatically. If three arguments are specified,
+                  the first argument is the cooling device specifier.
 
               contribution:
                 $ref: /schemas/types.yaml#/definitions/uint32
-- 
2.43.0

Re: [PATCH v2 12/12] dt-bindings: thermal: cooling-devices: Update support for 3 cells cooling device

[Krzysztof Kozlowski]

On Wed, Apr 22, 2026 at 07:43:01PM +0200, Daniel Lezcano wrote:
> From: Gaurav Kohli <gaurav.kohli@oss.qualcomm.com>
> 
> Extend the thermal cooling device binding to support a 3 cells specifier
> along with the 2 cells format.
> 
> Update #cooling-cells property to enum to support both 2 and 3 arguments.
> 
> Fix pwm-fan.yaml to restrict the number of cells to 'const: 2'
> 
> Signed-off-by: Gaurav Kohli <gaurav.kohli@oss.qualcomm.com>
> Signed-off-by: Daniel Lezcano <daniel.lezcano@oss.qualcomm.com>

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

Best regards,
Krzysztof