Re: [PATCH] backlight: use of_find_backlight_by_node stub when backlight class disabled

[Lee Jones <lee.jones@linaro.org>]

On Mon, 03 Nov 2014, Lee Jones wrote:

> On Wed, 29 Oct 2014, Heiko Stübner wrote:
> 
> > Drivers may want to search for an optional backlight even when the backlight
> > class is disabled. In this case the linker would miss the function referenced
> > in the backlight header.
> > 
> > Therefore use the stub function also when the backlight class is disabled.
> > 
> > Signed-off-by: Heiko Stuebner <heiko@sntech.de>
> > ---
> >  include/linux/backlight.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> Applied to Backlight -next with Jingoo's Ack.

I've removed this patch, as it causes unexpected:

  Redefinition of of_find_backlight_by_node()

... error.

Bear in mind that defined(CONFIG_BACKLIGHT_CLASS_DEVICE) is false if
it's built in as a module.  Change to nested #ifdefs instead.

> > diff --git a/include/linux/backlight.h b/include/linux/backlight.h
> > index adb14a8..d9cb644 100644
> > --- a/include/linux/backlight.h
> > +++ b/include/linux/backlight.h
> > @@ -157,7 +157,7 @@ struct generic_bl_info {
> >  	void (*kick_battery)(void);
> >  };
> >  
> > -#ifdef CONFIG_OF
> > +#if defined(CONFIG_OF) && defined(CONFIG_BACKLIGHT_CLASS_DEVICE)
> >  struct backlight_device *of_find_backlight_by_node(struct device_node *node);
> >  #else
> >  static inline struct backlight_device *
> 

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
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