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Date:   Thu, 15 Jun 2023 18:36:07 +0300
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Bartosz Golaszewski <bartosz.golaszewski@linaro.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        Alexander Stein <alexander.stein@ew.tq-group.com>,
        linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org,
        Bartosz Golaszewski <brgl@bgdev.pl>
Subject: Re: [PATCH v3 3/5] gpio: aggregator: Prevent collisions between DT
 and user device IDs
Message-ID: <ZIsv51766AXAiQ7E@smile.fi.intel.com>
References: <20230615132023.13801-1-andriy.shevchenko@linux.intel.com>
 <20230615132023.13801-4-andriy.shevchenko@linux.intel.com>
 <CAMuHMdVAwKCUnOeuz_PE6ijtfTVf8a3rTQZ=JvThOmqytu5HCA@mail.gmail.com>
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On Thu, Jun 15, 2023 at 04:54:14PM +0200, Geert Uytterhoeven wrote:
> On Thu, Jun 15, 2023 at 3:51 PM Andy Shevchenko
> <andriy.shevchenko@linux.intel.com> wrote:
> > In case we have a device instantiated via DT or other means than
> > via new_device sysfs node, the collision with the latter is possible.
> > Prevent such collisions by allocating user instantiated devices with
> > higher IDs, currently set to 1024.
> 
> Can you please elaborate? How exactly is this possible?
> 
> Aggregators instantiated through sysfs are named "gpio-aggregator.<n>",
> and are IDR-based.
> Aggregators instantiated from DT are named "<unit-address>.<node-name>".
> How can this conflict? When instantiated from ACPI?
> What am I missing?

Nothing. It's me who misunderstood how OF platform device naming schema works.

So this patch can be discarded as we never will have gpio-delay available for
removal via delete_device sysfs node.

Bart, tell me if you need a new version w/o this patch (but note that b4 can
handle this case with

	b4 -slt -P1,2,4,5 ...

).

-- 
With Best Regards,
Andy Shevchenko