Re: [PATCH v2 2/2] dt-bindings: mailbox: qcom: Add IPCC support for Glymur Platform

[Krzysztof Kozlowski <krzk@kernel.org>]

On 29/10/2025 18:23, Bjorn Andersson wrote:
> On Wed, Oct 29, 2025 at 04:49:30PM +0100, Krzysztof Kozlowski wrote:
>> On 29/10/2025 09:15, Jingyi Wang wrote:
>>> diff --git a/include/dt-bindings/mailbox/qcom,glymur-ipcc.h b/include/dt-bindings/mailbox/qcom,glymur-ipcc.h
>>> new file mode 100644
>>> index 000000000000..3ab8189974a5
>>> --- /dev/null
>>> +++ b/include/dt-bindings/mailbox/qcom,glymur-ipcc.h
>>> @@ -0,0 +1,68 @@
>>> +/* SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause */
>>> +/*
>>> + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
>>> + */
>>> +
>>> +#ifndef __DT_BINDINGS_MAILBOX_IPCC_GLYMUR_H
>>> +#define __DT_BINDINGS_MAILBOX_IPCC_GLYMUR_H
>>> +
>>> +/* Glymur physical client IDs */
>>> +#define IPCC_MPROC_AOP			0
>>
>>
>> Here the same - not used by Linux.
> 
> How is this different from e.g.:
> 
> include/dt-bindings/interrupt-controller/arm-gic.h:#define GIC_SPI 0

$ git grep GIC_SPI
drivers/irqchip/irq-mchp-eic.c

How is this not used by Linux? What is drivers/irqchip/foo.c if not a
Linux driver?

> 
> Perhaps I'm misunderstanding what you're saying here.
> 
>> Don't add these, they are really not
>> necessary and they are not helping anyhow. For longer explanation see 2
>> year thread for PMIC ADC v7.
>>
> 
> I'm sorry, I'm not able to wrangle a lore query for this, can you please
> provide a link?

"adc v7 qcom" and then my last two or three replies in that thread:
https://lore.kernel.org/all/d7627a5d-893a-4bc3-8b67-c151ee0bea32@kernel.org/

> 
>> Or provide explanation in terms what Linux interface you are binding
>> here (please focus on Linux or other SW).
>>
> 
> Don't we use include/dt-bindings to define hardware constants for use in

No, we do not.

> dt source as well? Has this changed?

Yes, 5 years ago or more when we noticed people do it unnecessarily. You
know, it is difficult to notice it, because we look at bindings and they
seem fine. Finding that something is not used requires more effort which
we usually do not care.

I have few bookmarks but not necessarily the earliest, just something I
managed to find because people ask the same:

2014 (so more than 5 years ago!):
https://lore.kernel.org/all/201401111415.29395.arnd@arndb.de/

A bit newer:
https://lore.kernel.org/linux-devicetree/CAK8P3a0fDJQvGLEtG0fxLkG08Fh9V7LEMPsx4AaS+2Ldo_xWxw@mail.gmail.com/

https://lore.kernel.org/linux-devicetree/CAK8P3a1APzs74YTcZ=m43G3zrmwJZKcYSTvV5eDDQX-37UY7Tw@mail.gmail.com/

https://lore.kernel.org/linux-devicetree/418c5f0c-5279-41f5-3705-345ec9a97ea2@linaro.org/

https://lore.kernel.org/linux-devicetree/c088e01c-0714-82be-8347-6140daf56640@linaro.org/

https://lore.kernel.org/linux-devicetree/579a1569-7bba-491f-ba5e-7cfcb34ccc1f@linaro.org/


Best regards,
Krzysztof