Re: [PATCH v2 2/8] drm: Add drm_crtc_mode_valid()

[Daniel Vetter <daniel@ffwll.ch>]

On Tue, May 09, 2017 at 06:00:09PM +0100, Jose Abreu wrote:
> Add a new helper to call crtc->mode_valid callback.
> 
> Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Signed-off-by: Jose Abreu <joabreu@synopsys.com>
> Cc: Carlos Palminha <palminha@synopsys.com>
> Cc: Alexey Brodkin <abrodkin@synopsys.com>
> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Cc: Dave Airlie <airlied@linux.ie>
> Cc: Andrzej Hajda <a.hajda@samsung.com>
> Cc: Archit Taneja <architt@codeaurora.org>
> ---
>  drivers/gpu/drm/drm_crtc.c          | 22 ++++++++++++++++++++++
>  drivers/gpu/drm/drm_crtc_internal.h |  3 +++
>  2 files changed, 25 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index 5af25ce..07ae705 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -38,6 +38,7 @@
>  #include <drm/drm_crtc.h>
>  #include <drm/drm_edid.h>
>  #include <drm/drm_fourcc.h>
> +#include <drm/drm_modeset_helper_vtables.h>
>  #include <drm/drm_modeset_lock.h>
>  #include <drm/drm_atomic.h>
>  #include <drm/drm_auth.h>
> @@ -741,3 +742,24 @@ int drm_mode_crtc_set_obj_prop(struct drm_mode_object *obj,
>  
>  	return ret;
>  }
> +
> +/**
> + * drm_crtc_mode_valid - call crtc->mode_valid callback, if any.
> + * @crtc: crtc
> + * @mode: mode to be validated
> + *
> + * If no mode_valid callback is available this will return MODE_OK.
> + *
> + * Returns: drm_mode_status Enum
> + */
> +enum drm_mode_status drm_crtc_mode_valid(struct drm_crtc *crtc,
> +					 const struct drm_display_mode *mode)
> +{
> +	const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;

This is clearly a helper func, but you place it into the core and
EXPORT_SYMBOL it. Imo this should be entirely internal to the helpers,
perhaps just stuff them all into drm_probe_helpers.c? Header file would be
drm_crtc_helper_internal.h.

That also means no need for kernel-doc (only the driver api is formally
documented) and then these 3 patches are so tiny it's better to squash
them into the patch that adds their users.

Thanks, Daniel
> +
> +	if (!crtc_funcs || !crtc_funcs->mode_valid)
> +		return MODE_OK;
> +
> +	return crtc_funcs->mode_valid(crtc, mode);
> +}
> +EXPORT_SYMBOL(drm_crtc_mode_valid);
> diff --git a/drivers/gpu/drm/drm_crtc_internal.h b/drivers/gpu/drm/drm_crtc_internal.h
> index d077c54..3800abd 100644
> --- a/drivers/gpu/drm/drm_crtc_internal.h
> +++ b/drivers/gpu/drm/drm_crtc_internal.h
> @@ -45,6 +45,9 @@ int drm_crtc_check_viewport(const struct drm_crtc *crtc,
>  
>  struct dma_fence *drm_crtc_create_fence(struct drm_crtc *crtc);
>  
> +enum drm_mode_status drm_crtc_mode_valid(struct drm_crtc *crtc,
> +					 const struct drm_display_mode *mode);
> +
>  /* IOCTLs */
>  int drm_mode_getcrtc(struct drm_device *dev,
>  		     void *data, struct drm_file *file_priv);
> -- 
> 1.9.1
> 
> 

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