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References: <20210118012246.1858892-1-zhangzhijie@loongson.cn> <fd296f78-86df-e933-78ff-4b66e978e730@suse.de>
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From:   Daniel Vetter <daniel@ffwll.ch>
Date:   Mon, 18 Jan 2021 08:46:14 +0100
Message-ID: <CAKMK7uHsRS3e2CSnHMw=LKyxVBuL88i7a677F_zPwOLyJ76Org@mail.gmail.com>
Subject: Re: [PATCH v3] drm: Improve the output_poll_changed description
To:     Thomas Zimmermann <tzimmermann@suse.de>
Cc:     "ZhiJie.Zhang" <zhangzhijie@loongson.cn>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Dave Airlie <airlied@linux.ie>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Mon, Jan 18, 2021 at 7:53 AM Thomas Zimmermann <tzimmermann@suse.de> wro=
te:
>
> Hi
>
> Am 18.01.21 um 02:22 schrieb ZhiJie.Zhang:
> > From: zhangzhijie <zhangzhijie@loongson.cn>
> >
> > this callback was used by drm_kms_helper_hotplug_event()
> >
> > V2: (Thanks for Daniel's suggestions)
> > - remove the FIXME below.since with the drm_client
> > - infrastructure and the generic fbdev emulation we've
> > - resolved this all very neatly now.
> >
> > V3: Add comments that This hook is deprecated
> > - new implementation methods instead of this hook
> >
> > Signed-off-by: zhangzhijie <zhangzhijie@loongson.cn>
> > Signed-off-by: ZhiJie.Zhang <zhangzhijie@loongson.cn>
> > ---
> >   include/drm/drm_mode_config.h | 12 ++++++------
> >   1 file changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_confi=
g.h
> > index ab424ddd7665..a084482d579a 100644
> > --- a/include/drm/drm_mode_config.h
> > +++ b/include/drm/drm_mode_config.h
> > @@ -103,14 +103,14 @@ struct drm_mode_config_funcs {
> >        * Callback used by helpers to inform the driver of output config=
uration
> >        * changes.
> >        *
> > -      * Drivers implementing fbdev emulation with the helpers can call
> > -      * drm_fb_helper_hotplug_changed from this hook to inform the fbd=
ev
> > +      * Drivers implementing fbdev emulation with the helpers. Drivers=
 use
> > +      * drm_kms_helper_hotplug_event() to call this hook to inform the=
 fbdev
>
> I don't understand this. Maybe it's "Drivers implementing fbdev
> emulation use drm_kms_helper_hotplug_event() to call ..." ?

Yeah this just doesn't make sense now, this is not the interesting
information. Removing the hint that this should be implemented using
drm_fb_helper_hotplug_changed is really not good.
-Daniel

>
> Best regards
> Thomas
>
> >        * helper of output changes.
> >        *
> > -      * FIXME:
> > -      *
> > -      * Except that there's no vtable for device-level helper callback=
s
> > -      * there's no reason this is a core function.
> > +      * This hook is deprecated, drivers should instead use
> > +      * drm_fbdev_generic_setup() which takes care of any necessary
> > +      * hotplug event forwarding already without further involvement b=
y
> > +      * the driver.
> >        */
> >       void (*output_poll_changed)(struct drm_device *dev);
> >
> >
>
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 N=C3=BCrnberg, Germany
> (HRB 36809, AG N=C3=BCrnberg)
> Gesch=C3=A4ftsf=C3=BChrer: Felix Imend=C3=B6rffer
>


--=20
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch