Re: [PATCH 1/2] dt-bindings: probe-control: add probe control driver

[Nayeemahmed Badebade <nayeemahmed.badebade@sony.com>]

On Tue, Sep 17, 2024 at 11:00:23AM +0200, Krzysztof Kozlowski wrote:

Hi Krzysztof,

Sorry for the delay in our response. 
Thank you for checking our patchset and sharing your comments for it.
We appreciate your feedback.


> On 11/09/2024 16:23, Nayeemahmed Badebade wrote:
> > Device tree binding document for the probe-control driver
> 
> Describe the hardware, not driver...
> 
> > 
> > Signed-off-by: Toyama Yoshihiro <yoshihiro.toyama@sony.com>
> > Signed-off-by: Nayeemahmed Badebade <nayeemahmed.badebade@sony.com>
> > ---
> >  .../probe-control/linux,probe-controller.yaml | 59 +++++++++++++++++++
> >  1 file changed, 59 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/probe-control/linux,probe-controller.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/probe-control/linux,probe-controller.yaml b/Documentation/devicetree/bindings/probe-control/linux,probe-controller.yaml
> > new file mode 100644
> > index 000000000000..1945a7a5ab3c
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/probe-control/linux,probe-controller.yaml
> > @@ -0,0 +1,59 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +# Copyright (c) 2024 Sony Group Corporation
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/linux,probe-controller.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Probe control device
> > +
> > +maintainers:
> > +  - Nayeemahmed Badebade <nayeemahmed.badebade@sony.com>
> > +  - Toyama Yoshihiro <yoshihiro.toyama@sony.com>
> > +
> > +description: |
> > +  This binding is for controlling the probes of a set of devices in the system.
> > +  Probe control device is a dummy device that can be used to control the probe
> > +  of a group of devices. To have finer control, the devices can further be
> > +  divided into multiple groups and for each group a probe control device can
> > +  be assigned. This way, individual groups can be managed independently.
> > +  For example, one group can be for pcie based devices and other can be
> > +  scsi or usb devices.
> > +  Probe control device is provider node and the devices whose probes need to be
> > +  controlled, are consumer nodes. To establish control over consumer device
> > +  probes, each consumer device node need to refer the probe control provider
> > +  node by the phandle.
> 
> So all this looks like not suitable for DT at all.
> 

We understand now that this approach is not suitable for DT.

> > +
> > +properties:
> > +  compatible:
> > +    const: linux,probe-control
> > +
> > +  probe-control-supply:
> > +    description:
> > +      Phandle to the probe control provider node.
> 
> I don't understand this. Regulator supply is not a provider node.
> 
> > +
> > +required:
> > +  - compatible
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    // The node below defines a probe control device/provider node
> > +    prb_ctrl_dev_0: prb_ctrl_dev_0 {
> 
> No underscores in node names.

Got it.

> 
> > +        compatible = "linux,probe-control";
> 
> Where are the resources? It's empty?
>

Yes, this was a dummy device node for controlling probes of actual devices.
But we understand now that this approach is not right.
Thank you.

Regards,
Nayeem