drm: simple_kms_helper: Add mode_valid() callback support
The PL111 needs to filter valid modes based on memory bandwidth.
I guess it is a pretty simple operation, so we can still claim
the DRM KMS helper pipeline is simple after adding this (optional)
vtable callback.
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180220072859.3386-1-linus.walleij@linaro.org
diff --git a/include/drm/drm_simple_kms_helper.h b/include/drm/drm_simple_kms_helper.h
index 6d9adbb..d9e4c3c 100644
--- a/include/drm/drm_simple_kms_helper.h
+++ b/include/drm/drm_simple_kms_helper.h
@@ -22,6 +22,20 @@ struct drm_simple_display_pipe;
*/
struct drm_simple_display_pipe_funcs {
/**
+ * @mode_valid:
+ *
+ * This function is called to filter out valid modes from the
+ * suggestions suggested by the bridge or display. This optional
+ * hook is passed in when initializing the pipeline.
+ *
+ * RETURNS:
+ *
+ * drm_mode_status Enum
+ */
+ enum drm_mode_status (*mode_valid)(struct drm_crtc *crtc,
+ const struct drm_display_mode *mode);
+
+ /**
* @enable:
*
* This function should be used to enable the pipeline.