RE: [EXT] Re: [v5,2/2] Documentation: dt: binding: rtc: add binding for ftm alarm driver

From: Biwen Li
Date: Wed Jul 17 2019 - 06:05:21 EST


>
> Caution: EXT Email
>
> On Tue, Jul 16, 2019 at 4:26 AM Biwen Li <biwen.li@xxxxxxx> wrote:
> >
> > The patch adds binding for ftm alarm driver
>
> Bindings are for h/w, not drivers...
>
> 'dt-bindings: rtc: ...' for the subject prefix.
I will correct it in v6.
>
> >
> > Signed-off-by: Biwen Li <biwen.li@xxxxxxx>
> > ---
> > Change in v5:
> > - None
> >
> > Change in v4:
> > - add note about dts and kernel options
> > - add aliases in example
> >
> > Change in v3:
> > - remove reg-names property
> > - correct cells number
> >
> > Change in v2:
> > - replace ls1043a with ls1088a as example
> > - add rcpm node and fsl,rcpm-wakeup property
> >
> >
> > .../bindings/rtc/rtc-fsl-ftm-alarm.txt | 49 +++++++++++++++++++
> > 1 file changed, 49 insertions(+)
> > create mode 100644
> > Documentation/devicetree/bindings/rtc/rtc-fsl-ftm-alarm.txt
> >
> > diff --git
> > a/Documentation/devicetree/bindings/rtc/rtc-fsl-ftm-alarm.txt
> > b/Documentation/devicetree/bindings/rtc/rtc-fsl-ftm-alarm.txt
> > new file mode 100644
> > index 000000000000..fb018065406c
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/rtc/rtc-fsl-ftm-alarm.txt
> > @@ -0,0 +1,49 @@
> > +Freescale FlexTimer Module (FTM) Alarm
> > +
> > +Note:
> > +- The driver depends on RCPM driver
> > + to wake up system in sleep.
> > +- Need stop using RTC_HCTOSYS or use the DT aliases
> > + to ensure the driver is not used as the primary RTC.
> > + (Select DT aliases defaultly)
>
> This is Linux specific and not relevant to the binding.
Ok, I will remove all of the Note in v6.
>
> > +
> > +Required properties:
> > +- compatible : Should be "fsl,<chip>-ftm-alarm", the
> > + supported chips include
> > + "fsl,ls1012a-ftm-alarm"
> > + "fsl,ls1021a-ftm-alarm"
> > + "fsl,ls1028a-ftm-alarm"
> > + "fsl,ls1043a-ftm-alarm"
> > + "fsl,ls1046a-ftm-alarm"
> > + "fsl,ls1088a-ftm-alarm"
> > + "fsl,ls208xa-ftm-alarm"
> > +- reg : Specifies base physical address and size of the register sets
> > +for the
> > + FlexTimer Module and base physical address of IP Powerdown
> > +Exception Control
> > + Register.
> > +- interrupts : Should be the FlexTimer Module interrupt.
> > +- fsl,rcpm-wakeup property and rcpm node : Please refer
> > + Documentation/devicetree/bindings/soc/fsl/rcpm.txt
> > +
> > +Optional properties:
> > +- big-endian: If the host controller is big-endian mode, specify this property.
> > + The default endian mode is little-endian.
> > +
> > +Example:
> > +aliases {
> > + ...
> > + rtc1 = ftm_alarm0; /* Use flextimer alarm driver as /dev/rtc1 */
> > + ...
> > +};
>
> Drop the aliases part. It's not going to work when this is converted to DT schema
> and the comment is Linux specific.
Sorry,I can't drop the aliases part. If any user uses the alarm driver as rtc0,
the user will get wrong time from /dev/rtc0.It is very important.
>
> > +
> > +rcpm: rcpm@1e34040 {
> > + compatible = "fsl,ls1088a-rcpm", "fsl,qoriq-rcpm-2.1+";
> > + reg = <0x0 0x1e34040 0x0 0x18>;
> > + fsl,#rcpm-wakeup-cells = <6>;
>
> Before there are any users of this, either drop it if it is not variable or the correct
> form would be '#fsl,rcpm-wakeup-cells'.
I will replace 'fsl,#rcpm-wakeup-cells' with '#fsl,rcpm-wakeup-cells' in v6.
>
> > +};
> > +
> > +ftm_alarm0: timer@2800000 {
> > + compatible = "fsl,ls1088a-ftm-alarm";
> > + reg = <0x0 0x2800000 0x0 0x10000>;
> > + fsl,rcpm-wakeup = <&rcpm 0x0 0x0 0x0 0x0 0x4000 0x0>;
> > + interrupts = <0 44 4>;
> > +};
> > --
> > 2.17.1
> >