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From:   Jani Nikula <jani.nikula@intel.com>
To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Pin-yen Lin <treapking@chromium.org>
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Subject: Re: [PATCH v14 03/10] drm/display: Add Type-C switch helpers
In-Reply-To: <ZBrgD61p/p17IOJL@smile.fi.intel.com>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo
References: <20230322104639.221402-1-treapking@chromium.org>
 <20230322104639.221402-4-treapking@chromium.org>
 <ZBrgD61p/p17IOJL@smile.fi.intel.com>
Date:   Wed, 22 Mar 2023 18:27:56 +0200
Message-ID: <87edpg7nub.fsf@intel.com>
MIME-Version: 1.0
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On Wed, 22 Mar 2023, Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> On Wed, Mar 22, 2023 at 06:46:32PM +0800, Pin-yen Lin wrote:
>> +#ifdef CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER
>
> Ah, maybe this should use IS_REACHABLE() ?

Personally, I think IS_REACHABLE() is a build-time band-aid solution to
a problem that should be solved in Kconfig. :p

I think it always means there's a configuration combo that shouldn't
exist, and it's a surprise to the user when they've configured
something, Kconfig has deemed it a valid configuration, but they don't
get the feature they want.

As a user, how would they even debug that case? Double check configs,
don't see anything wrong.


BR,
Jani.


-- 
Jani Nikula, Intel Open Source Graphics Center