[PATCH 1/3] dt-bindings: thermal: gs101-tmu: add Exynos850 compatible

[Alexey Klimov]

Document the `samsung,exynos850-tmu-top` compatible string for the
Exynos850 SoC.

Unlike the GS101, where the ACPM firmware handles most of the TMU
initialization and threshold configuration, the Exynos850 firmware
implements a significantly smaller subset of TMU IPC commands.
Consequently, the Application Processor requires broader direct
MMIO access to initialize the thermal unit, configure thresholds,
clear interrupts and collect calibration data.

Signed-off-by: Alexey Klimov <alexey.klimov@xxxxxxxxxx>
---
 .../bindings/thermal/google,gs101-tmu-top.yaml     | 26 +++++++++++++++-------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/Documentation/devicetree/bindings/thermal/google,gs101-tmu-top.yaml b/Documentation/devicetree/bindings/thermal/google,gs101-tmu-top.yaml
index 75560ebca48d..bea208cd4619 100644
--- a/Documentation/devicetree/bindings/thermal/google,gs101-tmu-top.yaml
+++ b/Documentation/devicetree/bindings/thermal/google,gs101-tmu-top.yaml
@@ -15,17 +15,27 @@ description:
   both direct register-level access and firmware-mediated management
   via the ACPM (Alive Clock and Power Manager) firmware.
 
-  On these platforms, the hardware is managed in a hybrid fashion. The
-  Application Processor (AP) maintains direct memory-mapped access
-  exclusively to the interrupt pending registers to identify thermal
-  events. All other functional aspects - including sensor
-  initialization, threshold configuration, and temperature acquisition
-  - are handled by the ACPM firmware. The AP coordinates these
-  operations through the ACPM IPC protocol.
+  On these platforms, the hardware is managed in a hybrid fashion, though
+  the distribution of responsibilities between the Application Processor
+  (AP) and the ACPM firmware varies by SoC.
+
+  On the GS101, the AP maintains direct memory-mapped access exclusively
+  to the interrupt pending registers to identify thermal events. All other
+  functional aspects - including sensor initialization, threshold
+  configuration, and temperature acquisition - are handled by the ACPM
+  firmware. The AP coordinates these operations through the ACPM IPC protocol.
+
+  On the Exynos850, the ACPM firmware implements a smaller subset of TMU IPC
+  commands (mainly temperature querying, basic TMU initialization, and power
+  state management). Consequently, the AP is responsible for register-level
+  access to initialize the thermal unit, configure thresholds and handle
+  interrupts via MMIO.
 
 properties:
   compatible:
-    const: google,gs101-tmu-top
+    enum:
+      - google,gs101-tmu-top
+      - samsung,exynos850-tmu-top
 
   reg:
     maxItems: 1

-- 
2.51.0