Date: Thu, 7 Apr 2016 17:33:28 -0700
From: Stephen Boyd <sboyd@codeaurora.org>
To: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: linux-clk@vger.kernel.org, Ralf Baechle <ralf@linux-mips.org>,
        Michael Turquette <mturquette@baylibre.com>, linux-mips@linux-mips.org,
        linux-sh@vger.kernel.org, Haojian Zhuang <haojian.zhuang@gmail.com>,
        Eric Miao <eric.y.miao@gmail.com>,
        Hartley Sweeten <hsweeten@visionengravers.com>,
        Greg Ungerer <gerg@uclinux.org>, Ryan Mallon <rmallon@gmail.com>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Steven Miao <realmz6@gmail.com>, Simon Horman <horms@verge.net.au>,
        Wan ZongShun <mcuos.com@gmail.com>, Rich Felker <dalias@libc.org>,
        Yoshinori Sato <ysato@users.sourceforge.jp>,
        adi-buildroot-devel@lists.sourceforge.net,
        Russell King <linux@arm.linux.org.uk>, linux-m68k@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-renesas-soc@vger.kernel.org, Magnus Damm <magnus.damm@gmail.com>,
        John Crispin <blogic@openwrt.org>
Subject: Re: [PATCH v2] clk: let clk_disable() return immediately if clk is
 NULL or error
Message-ID: <20160408003328.GA14441@codeaurora.org>
References: <1459821083-28116-1-git-send-email-yamada.masahiro@socionext.com>
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On 04/05, Masahiro Yamada wrote:
> The clk_disable() in the common clock framework (drivers/clk/clk.c)
> returns immediately if a given clk is NULL or an error pointer.  It
> allows clock consumers to call clk_disable() without IS_ERR_OR_NULL
> checking if drivers are only used with the common clock framework.
> 
> Unfortunately, NULL/error checking is missing from some of non-common
> clk_disable() implementations.  This prevents us from completely
> dropping NULL/error checking from callers.  Let's make it tree-wide
> consistent by adding IS_ERR_OR_NULL(clk) to all callees.
> 
> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> Acked-by: Greg Ungerer <gerg@uclinux.org>
> Acked-by: Wan Zongshun <mcuos.com@gmail.com>
> ---
> 
> Stephen,
> 
> This patch has been unapplied for a long time.
> 
> Please let me know if there is something wrong with this patch.
> 

I'm mostly confused why we wouldn't want to encourage people to
call clk_disable or unprepare on a clk that's an error pointer.
Typically an error pointer should be dealt with, instead of
silently ignored, so why wasn't it dealt with by passing it up
the probe() path?

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