[PATCH] dt-bindings: thermal: qcom-spmi-temp-alarm: Improve thermal zone in example

[PATCH] dt-bindings: thermal: qcom-spmi-temp-alarm: Improve thermal zone in example

[Matthias Kaehlcke]

The current example for a thermal zone isn't very useful as reference
since it would result in a hardware shutdown at 145°C, instead of
allowing the system to try to shutdown gracefully. Without an ADC
channel a maximum of two trip points is useful in practice for this
sensor, with temperatures corresponding to the stage 1 and stage 2
'hardware trip points'. A critical trip point at stage 2 may allow the
system to shutdown before a hardware shutdown at stage 3 kicks in. It
should be noted though that by default the chip performs a 'partial
shutdown' when the temperature reaches stage 2, which may prevent an
orderly shutdown. The 'partial shutdown' can be disabled by software.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
---
 .../bindings/thermal/qcom-spmi-temp-alarm.txt         | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/Documentation/devicetree/bindings/thermal/qcom-spmi-temp-alarm.txt b/Documentation/devicetree/bindings/thermal/qcom-spmi-temp-alarm.txt
index 290ec06fa33a..cabf813595e5 100644
--- a/Documentation/devicetree/bindings/thermal/qcom-spmi-temp-alarm.txt
+++ b/Documentation/devicetree/bindings/thermal/qcom-spmi-temp-alarm.txt
@@ -36,19 +36,14 @@ Example:
 			thermal-sensors = <&pm8941_temp>;
 
 			trips {
-				passive {
-					temperature = <1050000>;
+				stage1 {
+					temperature = <105000>;
 					hysteresis = <2000>;
 					type = "passive";
 				};
-				alert {
+				stage2 {
 					temperature = <125000>;
 					hysteresis = <2000>;
-					type = "hot";
-				};
-				crit {
-					temperature = <145000>;
-					hysteresis = <2000>;
 					type = "critical";
 				};
 			};
-- 
2.18.0.233.g985f88cf7e-goog

Re: [PATCH] dt-bindings: thermal: qcom-spmi-temp-alarm: Improve thermal zone in example

[Doug Anderson]

Hi,

On Tue, Jul 24, 2018 at 4:50 PM, Matthias Kaehlcke <mka@chromium.org> wrote:
> The current example for a thermal zone isn't very useful as reference
> since it would result in a hardware shutdown at 145°C, instead of
> allowing the system to try to shutdown gracefully. Without an ADC
> channel a maximum of two trip points is useful in practice for this
> sensor, with temperatures corresponding to the stage 1 and stage 2
> 'hardware trip points'. A critical trip point at stage 2 may allow the
> system to shutdown before a hardware shutdown at stage 3 kicks in. It
> should be noted though that by default the chip performs a 'partial
> shutdown' when the temperature reaches stage 2, which may prevent an
> orderly shutdown. The 'partial shutdown' can be disabled by software.
>
> Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
> ---
>  .../bindings/thermal/qcom-spmi-temp-alarm.txt         | 11 +++--------
>  1 file changed, 3 insertions(+), 8 deletions(-)

Assuming your patch to disable the partial shutdown lands, then:

Reviewed-by: Douglas Anderson <dianders@chromium.org>

...if that patch doesn't land (or if someone disagrees with me and
thinks we need an extra property to disable the partial shutdown) then
we would need the example to be different.  Because of that, maybe
this should be appended to the end of your series which includes the
patch to disable partial shutdown?

-Doug