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Date:   Wed, 23 Oct 2019 10:39:28 +0200
From:   Daniel Vetter <daniel@ffwll.ch>
To:     Jani Nikula <jani.nikula@linux.intel.com>
Cc:     Mat King <mathewk@google.com>, Sean Paul <seanpaul@chromium.org>,
        Daniel Thompson <daniel.thompson@linaro.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        dri-devel <dri-devel@lists.freedesktop.org>, rafael@kernel.org,
        Greg KH <gregkh@linuxfoundation.org>,
        Ross Zwisler <zwisler@google.com>,
        Jingoo Han <jingoohan1@gmail.com>,
        Rajat Jain <rajatja@google.com>,
        Lee Jones <lee.jones@linaro.org>,
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        <ville.syrjala@linux.intel.com>, David Airlie <airlied@redhat.com>,
        Daniel Vetter <daniel.vetter@ffwll.ch>,
        Alexander Schremmer <alex@alexanderweb.de>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Subject: Re: New sysfs interface for privacy screens
Message-ID: <20191023083928.GR11828@phenom.ffwll.local>
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        David Airlie <airlied@redhat.com>,
        Alexander Schremmer <alex@alexanderweb.de>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>
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On Tue, Oct 08, 2019 at 09:13:51AM +0300, Jani Nikula wrote:
> On Mon, 07 Oct 2019, Mat King <mathewk@google.com> wrote:
> > That makes sense; just to confirm can a property be added or removed
> > after the connector is registered?
> 
> You need to create the property before registering the drm device. You
> can attach/detach the property later, but I should think you know by the
> time you're registering the connector whether it supports the privacy
> screen or not.

I don't think you can add/remove a property after the object you're
adding/removing the prop from has gone public (either with
drm_dev_register or drm_connector_register for hotplugged connectors).

I guess another gap we should cover with some WARN_ON?
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch