eglfs/kms: Add DRM atomic ModeSetting

This patch will allow to set the video mode with DRM atomic API when available.

Using Atomic ModeSetting will allow further to enable framebuffer upscaling which is
something not possible with DRM legacy API or at least not supported on all devices
in a reliable way.

Change-Id: Ie340585cf4cbf5d65555c9a7c547dcbadb327fc0
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>

1 files changed, 23 insertions, 11 deletions

diff --git a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmscreen.cpp b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmscreen.cpp
index f16869c009..e773e85433 100644
--- a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmscreen.cpp
+++ b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmscreen.cpp
@@ -211,17 +211,29 @@ void QEglFSKmsGbmScreen::ensureModeSet(uint32_t fb)
 
         if (doModeSet) {
             qCDebug(qLcEglfsKmsDebug, "Setting mode for screen %s", qPrintable(name()));
-            int ret = drmModeSetCrtc(fd,
-                                     op.crtc_id,
-                                     fb,
-                                     0, 0,
-                                     &op.connector_id, 1,
-                                     &op.modes[op.mode]);
-
-            if (ret == 0)
-                setPowerState(PowerStateOn);
-            else
-                qErrnoWarning(errno, "Could not set DRM mode for screen %s", qPrintable(name()));
+
+            if (device()->hasAtomicSupport()) {
+#if QT_CONFIG(drm_atomic)
+                drmModeAtomicReq *request = device()->atomic_request();
+                if (request) {
+                    drmModeAtomicAddProperty(request, op.connector_id, op.crtcIdPropertyId, op.crtc_id);
+                    drmModeAtomicAddProperty(request, op.crtc_id, op.modeIdPropertyId, op.mode_blob_id);
+                    drmModeAtomicAddProperty(request, op.crtc_id, op.activePropertyId, 1);
+                }
+#endif
+            } else {
+                int ret = drmModeSetCrtc(fd,
+                                         op.crtc_id,
+                                         fb,
+                                         0, 0,
+                                         &op.connector_id, 1,
+                                         &op.modes[op.mode]);
+
+                if (ret == 0)
+                    setPowerState(PowerStateOn);
+                else
+                    qErrnoWarning(errno, "Could not set DRM mode for screen %s", qPrintable(name()));
+            }
         }
     }
 }