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From: Arnd Bergmann <arnd@arndb.de>
To: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Philipp Zabel <p.zabel@pengutronix.de>
Subject: Re: [PATCH] reset: allow to pass NULL pointer to reset_control_put()
Date: Wed, 04 May 2016 14:35:01 +0200
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On Wednesday 04 May 2016 20:34:09 Masahiro Yamada wrote:
> I thought about that a bit,
> but there might be some (not nice) drivers that rely on the current behavior.
> I did not want to break any boards with my patch.
> 
> So, should it be
> 
>           if (!rstc)
>                     return;
> or, perhaps
> 
>           if (!rstc || WARN_ON_ONCE(IS_ERR(rstc)))
>                     return;

I think the latter is fine, but it would also be good which of the six
callers of the function actually rely on that behavior today, if any.

	Arnd