[PATCH 2/2] drm/fb-helper: Add a FIXME that generic_setup is very confusing

[Daniel Vetter]

On Fri, Dec 11, 2020 at 05:11:13PM +0100, Daniel Vetter wrote:
> I tried to fix this for real, but it's very sprawling and lots of
> drivers get this mildly wrong one way or the other.
> 
> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
> Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> Cc: Maxime Ripard <mripard at kernel.org>
> Cc: Thomas Zimmermann <tzimmermann at suse.de>
> Cc: David Airlie <airlied at linux.ie>
> Cc: Daniel Vetter <daniel at ffwll.ch>

Anyone feeling like an ack on this one?
-Daniel

> ---
>  drivers/gpu/drm/drm_fb_helper.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
> index 596255edf023..27deed4af015 100644
> --- a/drivers/gpu/drm/drm_fb_helper.c
> +++ b/drivers/gpu/drm/drm_fb_helper.c
> @@ -2494,6 +2494,11 @@ void drm_fbdev_generic_setup(struct drm_device *dev,
>  		return;
>  	}
>  
> +	/*
> +	 * FIXME: This mixes up depth with bpp, which results in a glorious
> +	 * mess, resulting in some drivers picking wrong fbdev defaults and
> +	 * others wrong preferred_depth defaults.
> +	 */
>  	if (!preferred_bpp)
>  		preferred_bpp = dev->mode_config.preferred_depth;
>  	if (!preferred_bpp)
> -- 
> 2.29.2
> 

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