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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Mon, 8 Jun 2020 09:39:51 +0200
Message-ID: <CAMuHMdUDcpCxmgdJtMRX7K9NvDxj+tDu33ebax0TOMBNZaygDw@mail.gmail.com>
Subject: Re: Re: [PATCH] media: vsp1: Fix runtime PM imbalance in vsp1_probe
To:     dinghao.liu@zju.edu.cn
Cc:     Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Kangjie Lu <kjlu@umn.edu>,
        Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Linux Media Mailing List <linux-media@vger.kernel.org>,
        Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Hi Dinghao,

On Mon, Jun 8, 2020 at 5:03 AM <dinghao.liu@zju.edu.cn> wrote:
> > > I wonder how many bugs we have today, and how many bugs will keep
> > > appearing in the future, due to this historical design mistake :-(
>
> Good question. It's hard to say if this is a design mistake (some use
> of this API does not check its return value and expects it always to
> increment the usage counter). But it does make developers misuse it easier.

On Renesas SoCs, I believe these can only fail if there's something
seriously wrong, which means the system could never have gotten this far
in the boot sequence anyway.  That's why I tend not to check the result
of pm_runtime_get_sync() at all (on drivers for Renesas SoCs).

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds