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Date:   Wed, 4 Jul 2018 12:17:20 +0200 (CEST)
From:   Nikolaus Voss <nikolaus.voss@loewensteinmedical.de>
To:     Sudeep Holla <sudeep.holla@arm.com>
cc:     Andy Shevchenko <andy.shevchenko@gmail.com>,
        Srinath Mannam <srinath.mannam@broadcom.com>,
        "Voss, Dr. Nikolaus" <Nikolaus.Dr.Voss@loewensteinmedical.de>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Len Brown <lenb@kernel.org>, Ray Jui <ray.jui@broadcom.com>,
        Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com>,
        Vikram Prakash <vikram.prakash@broadcom.com>,
        Scott Branden <scott.branden@broadcom.com>,
        ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        nv@vosn.de
Subject: Re: [RFC PATCH] ACPI: bus: match of_device_id using acpi device
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On Wed, 4 Jul 2018, Sudeep Holla wrote:
> On 04/07/18 10:32, Andy Shevchenko wrote:
>> On Wed, Jul 4, 2018 at 6:37 AM, Srinath Mannam
>> <srinath.mannam@broadcom.com> wrote:
>>> Hi Sudeep, Andy,
>>>
>>> Yes, This patch is to get of_device_id and then fetch data pointer.
>>>
>>> To add ACPI support in multiple drivers which are device-tree based
>>> and has list of of_device_ids, by using this function
>>> very minimal changes and can avoid acpi_device_id list in the driver.
>>> I will send driver changes where this function used to add ACPI
>>> support in following patches.
>>>
>>> Below are the changes added to add ACPI support in sdhci iproc driver
>>> using this function.
>>
>> So, did you get an ACPI ID for it?
>> That's how proper ACPI support should be done.
>>
>> P.S. What you are trying to do is being discussed with Nikolaus in [1].
>> I have to NAK your approach in any case. Sorry.
>>
>
> +1 on NACK for this and anything else that abuse PRP0001 as a short cut
> approach.

This is no abuse but exactly what PRP0001 is meant for. The basic idea of 
PRP0001 is to reuse DT "compatible" strings in ACPI namespace, see 
Documentation/acpi/enumeration.txt. Reusing also means getting 
access to the of_device_id.

Allocating an ACPI id for an already existing DT driver is redundant, isn't it?

Niko