From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jani Nikula <jani.nikula@linux.intel.com>
Date: Fri, 06 Nov 2015 12:52:27 +0000
Subject: Re: [PATCH] GPU-DRM-i915: Delete an unnecessary check before the function call "pwm_put"
Message-Id: <87h9kzl27o.fsf@intel.com>
List-Id: <kernel-janitors.vger.kernel.org>
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To: SF Markus Elfring <elfring@users.sourceforge.net>, Daniel Vetter <daniel.vetter@intel.com>, David Airlie <airlied@linux.ie>, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org
Cc: Julia Lawall <julia.lawall@lip6.fr>, kernel-janitors@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>

On Fri, 06 Nov 2015, SF Markus Elfring <elfring@users.sourceforge.net> wrote:
> From: Markus Elfring <elfring@users.sourceforge.net>
> Date: Fri, 6 Nov 2015 13:38:22 +0100
>
> The pwm_put() function tests whether its argument is NULL and then
> returns immediately. Thus the test around the call is not needed.

The compiler doesn't need it, but IMO it's useful documentation for
humans.

BR,
Jani.


>
> This issue was detected by using the Coccinelle software.
>
> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
> ---
>  drivers/gpu/drm/i915/intel_panel.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
> index a24df35..3d8d913 100644
> --- a/drivers/gpu/drm/i915/intel_panel.c
> +++ b/drivers/gpu/drm/i915/intel_panel.c
> @@ -1729,8 +1729,7 @@ void intel_panel_destroy_backlight(struct drm_connector *connector)
>  	struct intel_panel *panel = &intel_connector->panel;
>  
>  	/* dispose of the pwm */
> -	if (panel->backlight.pwm)
> -		pwm_put(panel->backlight.pwm);
> +	pwm_put(panel->backlight.pwm);
>  
>  	panel->backlight.present = false;
>  }

-- 
Jani Nikula, Intel Open Source Technology Center