eglfs/kms: make sure eglfs plane is always consistent

We need to make sure we update the eglfs plane properly even
when we are forcing the rendering plane index.

Change-Id: I0cd19fbc53c34f28d55708ba2c8e84278e1d7e7d
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>

1 files changed, 9 insertions, 3 deletions

diff --git a/src/platformsupport/kmsconvenience/qkmsdevice.cpp b/src/platformsupport/kmsconvenience/qkmsdevice.cpp
index 22033f58d9..99297c8a3c 100644
--- a/src/platformsupport/kmsconvenience/qkmsdevice.cpp
+++ b/src/platformsupport/kmsconvenience/qkmsdevice.cpp
@@ -409,9 +409,6 @@ QPlatformScreen *QKmsDevice::createScreenForConnector(drmModeResPtr resources,
     qCDebug(qLcKmsDebug, "Output %s can use %d planes: %s",
             connectorName.constData(), output.available_planes.count(), qPrintable(planeListStr));
 
-    if (output.eglfs_plane)
-        qCDebug(qLcKmsDebug, "Output eglfs plane is: %d", output.eglfs_plane->id);
-
     // This is for the EGLDevice/EGLStream backend. On some of those devices one
     // may want to target a pre-configured plane. It is probably useless for
     // eglfs_kms and others. Do not confuse with generic plane support (available_planes).
@@ -427,6 +424,12 @@ QPlatformScreen *QKmsDevice::createScreenForConnector(drmModeResPtr resources,
                     output.forced_plane_id = plane->plane_id;
                     qCDebug(qLcKmsDebug, "Forcing plane index %d, plane id %u (belongs to crtc id %u)",
                             idx, plane->plane_id, plane->crtc_id);
+
+                    for (const QKmsPlane &kmsplane : qAsConst(m_planes)) {
+                        if (kmsplane.id == output.forced_plane_id)
+                            output.eglfs_plane = (QKmsPlane*)&kmsplane;
+                    }
+
                     drmModeFreePlane(plane);
                 }
             } else {
@@ -435,6 +438,9 @@ QPlatformScreen *QKmsDevice::createScreenForConnector(drmModeResPtr resources,
         }
     }
 
+    if (output.eglfs_plane)
+        qCDebug(qLcKmsDebug, "Output eglfs plane is: %d", output.eglfs_plane->id);
+
     m_crtc_allocator |= (1 << output.crtc_index);
 
     vinfo->output = output;