[PATCH] drm/crtc-helpers: WARN when used with atomic drivers

[Gerd Hoffmann]

On Thu, Jan 10, 2019 at 11:30:45AM +0100, Daniel Vetter wrote:
> Motivated by an oversight of mine when looking at the atomic bochs
> conversion. For consistency also switch over to the same style as used
> elsewhere (e.g. in drm_mode_set_config_internal).
> 
> Cc: Gerd Hoffmann <kraxel at redhat.com>
> Cc: Noralf Trønnes <noralf at tronnes.org>
> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>

Reviewed-by: Gerd Hoffmann <kraxel at redhat.com>

> ---
>  drivers/gpu/drm/drm_crtc_helper.c | 18 ++++++++++++++----
>  1 file changed, 14 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
> index 23159eb494f1..91dc9b6386e7 100644
> --- a/drivers/gpu/drm/drm_crtc_helper.c
> +++ b/drivers/gpu/drm/drm_crtc_helper.c
> @@ -93,6 +93,8 @@ bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
>  	struct drm_connector_list_iter conn_iter;
>  	struct drm_device *dev = encoder->dev;
>  
> +	WARN_ON(drm_drv_uses_atomic_modeset(dev));
> +
>  	/*
>  	 * We can expect this mutex to be locked if we are not panicking.
>  	 * Locking is currently fubar in the panic handler.
> @@ -131,6 +133,8 @@ bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
>  	struct drm_encoder *encoder;
>  	struct drm_device *dev = crtc->dev;
>  
> +	WARN_ON(drm_drv_uses_atomic_modeset(dev));
> +
>  	/*
>  	 * We can expect this mutex to be locked if we are not panicking.
>  	 * Locking is currently fubar in the panic handler.
> @@ -212,8 +216,7 @@ static void __drm_helper_disable_unused_functions(struct drm_device *dev)
>   */
>  void drm_helper_disable_unused_functions(struct drm_device *dev)
>  {
> -	if (drm_core_check_feature(dev, DRIVER_ATOMIC))
> -		DRM_ERROR("Called for atomic driver, this is not what you want.\n");
> +	WARN_ON(drm_drv_uses_atomic_modeset(dev));
>  
>  	drm_modeset_lock_all(dev);
>  	__drm_helper_disable_unused_functions(dev);
> @@ -281,6 +284,8 @@ bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
>  	struct drm_encoder *encoder;
>  	bool ret = true;
>  
> +	WARN_ON(drm_drv_uses_atomic_modeset(dev));
> +
>  	drm_warn_on_modeset_not_all_locked(dev);
>  
>  	saved_enabled = crtc->enabled;
> @@ -540,6 +545,9 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set,
>  
>  	crtc_funcs = set->crtc->helper_private;
>  
> +	dev = set->crtc->dev;
> +	WARN_ON(drm_drv_uses_atomic_modeset(dev));
> +
>  	if (!set->mode)
>  		set->fb = NULL;
>  
> @@ -555,8 +563,6 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set,
>  		return 0;
>  	}
>  
> -	dev = set->crtc->dev;
> -
>  	drm_warn_on_modeset_not_all_locked(dev);
>  
>  	/*
> @@ -875,6 +881,8 @@ int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
>  	struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
>  	int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
>  
> +	WARN_ON(drm_drv_uses_atomic_modeset(connector->dev));
> +
>  	if (mode == connector->dpms)
>  		return 0;
>  
> @@ -946,6 +954,8 @@ void drm_helper_resume_force_mode(struct drm_device *dev)
>  	int encoder_dpms;
>  	bool ret;
>  
> +	WARN_ON(drm_drv_uses_atomic_modeset(dev));
> +
>  	drm_modeset_lock_all(dev);
>  	drm_for_each_crtc(crtc, dev) {
>  
> -- 
> 2.20.0.rc1
>