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From:   "Rafael J. Wysocki" <rafael@kernel.org>
Date:   Fri, 20 Oct 2023 19:11:53 +0200
Message-ID: <CAJZ5v0jvAeibnXSq92CBd1uXUgRnvsP0kEqfL8Du552=LT1dog@mail.gmail.com>
Subject: Re: [PATCH v1 4/8] ACPI: utils: use acpi_dev_uid_match() for matching _UID
To:     Raag Jadav <raag.jadav@intel.com>
Cc:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        rafael@kernel.org, len.brown@intel.com, robert.moore@intel.com,
        mika.westerberg@linux.intel.com, mark.rutland@arm.com,
        will@kernel.org, linux@roeck-us.net, linux-acpi@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        acpica-devel@lists.linuxfoundation.org, linux-gpio@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-hwmon@vger.kernel.org,
        mallikarjunappa.sangannavar@intel.com, bala.senthil@intel.com
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On Fri, Oct 20, 2023 at 1:38 PM Raag Jadav <raag.jadav@intel.com> wrote:
>
> On Fri, Oct 20, 2023 at 01:36:27PM +0300, Andy Shevchenko wrote:
> > On Fri, Oct 20, 2023 at 02:17:28PM +0530, Raag Jadav wrote:
> > > Convert manual _UID references to use standard ACPI helpers.
> >
> > Yes, while not so obvious this is the correct replacement.
> > Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>
> I think this is the only case which would suffer from the more obvious
> behaviour, i.e.
>
> bool acpi_dev_uid_match(struct acpi_device *adev, const char *uid2)
> {
>         const char *uid1 = acpi_device_uid(adev);
>
>         return uid1 && uid2 && !strcmp(uid1, uid2);
> }
>
> That said, we can't be particularly sure about it's potential future users,
> especially when the usage will not be limited to just ACPI core since we're
> exporting it.

I actually agree with this, so please switch over to the above.

The above is straightforward and easy to understand and if somebody
wants to treat uid2 == NULL as a match, let them check that explicitly
before calling this function.