RE: [PATCH V8 1/4] dt-bindings: fsl: scu: add thermal binding

From: Anson Huang
Date: Sat Feb 23 2019 - 21:53:56 EST


Hi, Eduardo

Best Regards!
Anson Huang

> -----Original Message-----
> From: Eduardo Valentin [mailto:edubezval@xxxxxxxxx]
> Sent: 2019年2月24日 5:38
> To: Anson Huang <anson.huang@xxxxxxx>
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> Subject: Re: [PATCH V8 1/4] dt-bindings: fsl: scu: add thermal binding
>
> On Thu, Feb 21, 2019 at 06:38:30AM +0000, Anson Huang wrote:
> > NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as system
> > controller, the system controller is in charge of system power, clock
> > and thermal sensors etc. management, Linux kernel has to communicate
> > with system controller via MU (message unit) IPC to get temperature
> > from thermal sensors, this patch adds binding doc for i.MX system
> > controller thermal driver.
> >
> > Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> > Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
> > ---
> > Changes since V7:
> > - remove unused property "tsens-num";
> > - improve the compatible description;
> > - update examples according to latest dts file.
> > ---
> > .../devicetree/bindings/arm/freescale/fsl,scu.txt | 19
> +++++++++++++++++++
> > 1 file changed, 19 insertions(+)
> >
> > diff --git
> > a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > index 72d481c..d89147e 100644
> > --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > @@ -122,6 +122,19 @@ RTC bindings based on SCU Message Protocol
> > Required properties:
> > - compatible: should be "fsl,imx8qxp-sc-rtc";
> >
> > +Thermal bindings based on SCU Message Protocol
> > +------------------------------------------------------------
> > +
> > +Required properties:
> > +- compatible: Should be :
> > + "fsl,imx8qxp-sc-thermal"
> > + followed by "fsl,imx-sc-thermal";
> > +
> > +- #thermal-sensor-cells: See
> Documentation/devicetree/bindings/thermal/thermal.txt
> > + for a description.
> > +
> > +- imx,sensor-resource-id: Property array to specify each thermal zone's
> sensor resource ID.
>
> If this is an array...
>
> > +
> > Example (imx8qxp):
> > -------------
> > lsio_mu1: mailbox@5d1c0000 {
> > @@ -168,6 +181,12 @@ firmware {
> > rtc: rtc {
> > compatible = "fsl,imx8qxp-sc-rtc";
> > };
> > +
> > + tsens: thermal-sensor {
> > + compatible = "fsl,imx8qxp-sc-thermal", "fsl,imx-sc-
> thermal";
> > + #thermal-sensor-cells = <0>;
> > + imx,sensor-resource-id = <IMX_SC_R_SYSTEM>;
>
> then this example should have an array, to be better express how this is
> supposed to work. Can you please resend this with an array instead?

On i.MX8QXP, there is ONLY 1 thermal zone available currently, but the thermal driver
is supposed to support multi thermal zones as well for i.MX8QM, in V9 patch set I just
sent, I use the " imx,sensor-resource-id " element count to determine how many thermal
sensors will be supported, so that we can also get rid of searching the thermal-zones' child
node, I improved the description as below, is it OK?

41 +- imx,sensor-resource-id: A single integer for single thermal zone's resource ID or
42 + an array of integers to specify each thermal zone's sensor
43 + resource ID.


Thanks,
Anson.

>
> > + };
> > };
> > };
> >
> > --
> > 2.7.4
> >