Re: [PATCH v3 2/4] dt-bindings: watchdog: add new binding for meson secure watchdog

[Xingyu Chen]

Hi,Rob

On 2019/10/30 4:51, Rob Herring wrote:
> On Mon, Oct 28, 2019 at 3:35 AM Xingyu Chen <xingyu.chen@xxxxxxxxxxx> wrote:
> > Hi, Rob
> >
> > On 2019/10/26 4:30, Rob Herring wrote:
> > > On Fri, Oct 25, 2019 at 02:13:02PM +0800, Xingyu Chen wrote:
> > > > The binding targets the Meson-A/C series compatible SoCs, in which the
> > > > watchdog registers are in secure world.
> > > >
> > > > Signed-off-by: Xingyu Chen <xingyu.chen@xxxxxxxxxxx>
> > > > ---
> > > >    .../bindings/watchdog/amlogic,meson-sec-wdt.yaml   | 34 ++++++++++++++++++++++
> > > >    1 file changed, 34 insertions(+)
> > > >    create mode 100644 Documentation/devicetree/bindings/watchdog/amlogic,meson-sec-wdt.yaml
> > > >
> > > > diff --git a/Documentation/devicetree/bindings/watchdog/amlogic,meson-sec-wdt.yaml b/Documentation/devicetree/bindings/watchdog/amlogic,meson-sec-wdt.yaml
> > > > new file mode 100644
> > > > index 00000000..0bbc807
> > > > --- /dev/null
> > > > +++ b/Documentation/devicetree/bindings/watchdog/amlogic,meson-sec-wdt.yaml
> > > > @@ -0,0 +1,34 @@
> > > > +# SPDX-License-Identifier: (GPL-2.0+ OR MIT)
> > > > +# Copyright (c) 2019 Amlogic, Inc
> > > > +%YAML 1.2
> > > > +---
> > > > +$id: "http://devicetree.org/schemas/power/amlogic,meson-sec-wdt.yaml#";
> > > > +$schema: "http://devicetree.org/meta-schemas/core.yaml#";
> > > > +
> > > > +title: Amlogic Meson Secure Watchdog Timer
> > > > +
> > > > +maintainers:
> > > > +  - Xingyu Chen <xingyu.chen@xxxxxxxxxxx>
> > > > +
> > > > +description: |+
> > > > +  Secure Watchdog Timer used in Meson-A/C series Compatible SoCs
> > > > +
> > > > +properties:
> > > > +  compatible:
> > > > +    enum:
> > > > +      - amlogic,meson-sec-wdt
> > >
> > > If there are no other properties, then you don't need this. Just have
> > > the secure firmware driver instantiate the watchdog.
> > I'am very sorry i don't understand how to initialize the watchdog driver
> > if the compatible property is removed, Could you give me more
> > suggestions or examples ï Thank you very much.
>
> platform_device_register_simple() from the secure firmware driver.
Thanks for your help. The device node of wdt looks useless if I use this 
function to register device. if so, how should I get the pointer to 
secure-monitor in wdt driver ? or should I use directly arm_smccc to 
access the secfw ?
> Rob
>
> .