drm/probe_helper: Add drm_connector_helper_funcs.mode_valid_ctx

This is just an atomic version of mode_valid, which is intended to be
used for situations where a driver might need to check the atomic state
of objects other than the connector itself. One such example is with
MST, where the maximum possible bandwidth on a connector can change
dynamically irregardless of the display configuration.

Changes since v1:
* Use new drm logging functions
* Make some corrections in the mode_valid_ctx kdoc
* Return error codes or 0 from ->mode_valid_ctx() on fail, and store the
  drm_mode_status in an additional function parameter
Changes since v2:
* Don't accidentally assign ret to mode->status on success, or we'll
  squash legitimate mode validation results
* Don't forget to assign MODE_OK to status in drm_connector_mode_valid()
  if we have no callbacks
* Drop leftover hunk in drm_modes.h around enum drm_mode_status
Changes since v3:
* s/return ret/return 0/ in drm_mode_validate_pipeline()
* Minor cleanup in drm_connector_mode_valid()

Tested-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Cc: Lee Shawn C <shawn.c.lee@intel.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200713170746.254388-2-lyude@redhat.com

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/gpu/drm/drm_crtc_helper_internal.h b/drivers/gpu/drm/drm_crtc_helper_internal.h
index f0a66ef47e5a..25ce42e79995 100644
--- a/drivers/gpu/drm/drm_crtc_helper_internal.h
+++ b/drivers/gpu/drm/drm_crtc_helper_internal.h
@@ -73,8 +73,11 @@ enum drm_mode_status drm_crtc_mode_valid(struct drm_crtc *crtc,
 					 const struct drm_display_mode *mode);
 enum drm_mode_status drm_encoder_mode_valid(struct drm_encoder *encoder,
 					    const struct drm_display_mode *mode);
-enum drm_mode_status drm_connector_mode_valid(struct drm_connector *connector,
-					      struct drm_display_mode *mode);
+int
+drm_connector_mode_valid(struct drm_connector *connector,
+			 struct drm_display_mode *mode,
+			 struct drm_modeset_acquire_ctx *ctx,
+			 enum drm_mode_status *status);
 
 struct drm_encoder *
 drm_connector_get_single_encoder(struct drm_connector *connector);