linux-kernel - Re: [PATCH v3 5/5] drm/fsl-dcu: only init fbdev if required

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Message-ID: <20161018074424.GX20761@phenom.ffwll.local>
Date:   Tue, 18 Oct 2016 09:44:24 +0200
From:   Daniel Vetter <daniel@...ll.ch>
To:     Stefan Agner <stefan@...er.ch>
Cc:     meng.yi@....com, dri-devel@...ts.freedesktop.org,
        jianwei.wang.chn@...il.com, linux-kernel@...r.kernel.org,
        alison.wang@...escale.com
Subject: Re: [PATCH v3 5/5] drm/fsl-dcu: only init fbdev if required

On Mon, Oct 17, 2016 at 02:33:21PM -0700, Stefan Agner wrote:
> There is no need to request a CMA backed framebuffer if fbdev
> emulation is not enabled.
> 
> Signed-off-by: Stefan Agner <stefan@...er.ch>
> ---
>  drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
> index e04efbe..3a5880c 100644
> --- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
> +++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
> @@ -87,7 +87,8 @@ static int fsl_dcu_load(struct drm_device *dev, unsigned long flags)
>  		goto done;
>  	dev->irq_enabled = true;
>  
> -	fsl_dcu_fbdev_init(dev);
> +	if (IS_ENABLED(CONFIG_DRM_FBDEV_EMULATION))
> +		fsl_dcu_fbdev_init(dev);

Totally not required, since this will all no-op out. Also, please nuke
that fsl_dcu_fbdv_init wrapper seems like pointless indirection.

And if there really is an issue with the cma helpers allocating an fb when
they should, then the correct fix is to fix that in the helpers, not in
the drivers.

Nack.
-Daniel
>  
>  	return 0;
>  done:
> -- 
> 2.10.0
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@...ts.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

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