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Message-ID: <5a003da4e38fcb50782664496fc37b84773a7813.camel@perches.com>
Subject: Re: [PATCH 1/8] drm/ingenic: Remove dead code
From:   Joe Perches <joe@perches.com>
To:     Thomas Zimmermann <tzimmermann@suse.de>,
        Paul Cercueil <paul@crapouillou.net>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>
Cc:     "H . Nikolaus Schaller" <hns@goldelico.com>,
        Paul Boddie <paul@boddie.org.uk>, list@opendingux.net,
        Sam Ravnborg <sam@ravnborg.org>, linux-mips@vger.kernel.org,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Date:   Sun, 08 Aug 2021 11:27:34 -0700
In-Reply-To: <ff06e53b-ba7e-5535-8931-ce7f7cdae5a6@suse.de>
References: <20210808134526.119198-1-paul@crapouillou.net>
         <20210808134526.119198-2-paul@crapouillou.net>
         <ff06e53b-ba7e-5535-8931-ce7f7cdae5a6@suse.de>
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On Sun, 2021-08-08 at 19:58 +0200, Thomas Zimmermann wrote:
> 
> Am 08.08.21 um 15:45 schrieb Paul Cercueil:
> > The priv->ipu_plane would get a different value further down the code,
> > without the first assigned value being read first; so the first
> > assignation can be dropped.
> > 
> > Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> 
> Acked-by: Thomas Zimmermann <tzimmermann@suse.de>

I think this is at best an incomplete description.

How is it known that this priv->ipu_plane assignment isn't
necessary for any path of any failure path after this assignment
and before the new assignment?

> > diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
[]
> > @@ -984,9 +984,6 @@ static int ingenic_drm_bind(struct device *dev, bool has_components)
> > ??	priv->dma_hwdescs->hwdesc_pal.cmd = JZ_LCD_CMD_ENABLE_PAL
> > ??		| (sizeof(priv->dma_hwdescs->palette) / 4);
> > 
> > -	if (soc_info->has_osd)
> > -		priv->ipu_plane = drm_plane_from_index(drm, 0);
> > -
> > ??	primary = priv->soc_info->has_osd ? &priv->f1 : &priv->f0;
> > 
> > ??	drm_plane_helper_add(primary, &ingenic_drm_plane_helper_funcs);
> > 
>