[PATCH v9 01/14] drm/atomic-helper: Add crtc check before checking plane

[Jun Nie]

Some display controller support flexible CRTC and DMA, such as the display
controllers in snapdragon SoCs. CRTC can be implemented with several mixers
in parallel, and plane fetching can be implemented with several DMA under
umberala of a virtual drm plane.

The mixer number is decided per panel resolution and clock rate constrain
first, which happens in CRTC side. Then plane is split per mixer number
and configure DMA accordingly.

To support such forthcoming usage case, CRTC checking shall happen before
checking plane. Add the checking in the drm_atomic_helper_check_modeset().

Signed-off-by: Jun Nie <jun.nie at linaro.org>
---
 drivers/gpu/drm/drm_atomic_helper.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 5302ab3248985d3e0a47e40fd3deb7ad0d9f775b..5bca4c9683838c38574c8cb7c0bc9d57960314fe 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -816,6 +816,25 @@ drm_atomic_helper_check_modeset(struct drm_device *dev,
 			return ret;
 	}
 
+	for_each_new_crtc_in_state(state, crtc, new_crtc_state, i) {
+		const struct drm_crtc_helper_funcs *funcs;
+
+		funcs = crtc->helper_private;
+
+		if (!funcs || !funcs->atomic_check)
+			continue;
+
+		ret = funcs->atomic_check(crtc, state);
+		if (ret) {
+			drm_dbg_atomic(crtc->dev,
+				       "[CRTC:%d:%s] atomic driver check failed\n",
+				       crtc->base.id, crtc->name);
+			return ret;
+		}
+	}
+
+
+
 	ret = mode_valid(state);
 	if (ret)
 		return ret;

-- 
2.34.1