Re: [PATCH v2] clk: let clk_disable() return immediately if clk is NULL or error

From: Stephen Boyd
Date: Thu Apr 07 2016 - 20:33:41 EST


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@xxxxxxxxxxxxx>
> Acked-by: Greg Ungerer <gerg@xxxxxxxxxxx>
> Acked-by: Wan Zongshun <mcuos.com@xxxxxxxxx>
> ---
>
> 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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