Re: [PATCH v2 01/22] drm: add clone mode check for CRTC

[Jani Nikula <jani.nikula@linux.intel.com>]

On Tue, 24 Sep 2024, Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
> Add helper to check if the given CRTC state is in clone mode
>
> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
> ---
>  include/drm/drm_crtc.h | 7 +++++++
>  1 file changed, 7 insertions(+)
>
> diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
> index 8b48a1974da3..ecb93e2c4afc 100644
> --- a/include/drm/drm_crtc.h
> +++ b/include/drm/drm_crtc.h
> @@ -1323,5 +1323,12 @@ static inline struct drm_crtc *drm_crtc_find(struct drm_device *dev,
>  
>  int drm_crtc_create_scaling_filter_property(struct drm_crtc *crtc,
>  					    unsigned int supported_filters);
> +static inline bool drm_crtc_in_clone_mode(struct drm_crtc_state *crtc_state)
> +{
> +	if (!crtc_state)
> +		return false;
> +
> +	return hweight32(crtc_state->encoder_mask) > 1;
> +}

What's the benefit of this being static inline?

You're implicitly depending on hweight32() being available, basically
<linux/bitops.h> being included. Maybe it already is, but it's the
accumulation of small and innocent looking things like this that then
explode the header dependencies, and make them harder to reduce.

BR,
Jani.

>  
>  #endif /* __DRM_CRTC_H__ */

-- 
Jani Nikula, Intel