eglfs_kms: Use eglGetPlatformDisplay when available

Task-number: QTBUG-60330
Change-Id: Ibbd74ae00d17fdc6ee9c86e758788dcca15ea4ff
Reviewed-by: Johan Helsing <johan.helsing@qt.io>

3 files changed, 32 insertions, 1 deletions

diff --git a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmintegration.cpp b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmintegration.cpp
index b6cdcf92b6..91fe575569 100644
--- a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmintegration.cpp
+++ b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmintegration.cpp
@@ -67,6 +67,36 @@ QEglFSKmsGbmIntegration::QEglFSKmsGbmIntegration()
     qCDebug(qLcEglfsKmsDebug, "New DRM/KMS via GBM integration created");
 }
 
+#ifndef EGL_EXT_platform_base
+typedef EGLDisplay (EGLAPIENTRYP PFNEGLGETPLATFORMDISPLAYEXTPROC) (EGLenum platform, void *native_display, const EGLint *attrib_list);
+#endif
+
+#ifndef EGL_PLATFORM_GBM_KHR
+#define EGL_PLATFORM_GBM_KHR 0x31D7
+#endif
+
+EGLDisplay QEglFSKmsGbmIntegration::createDisplay(EGLNativeDisplayType nativeDisplay)
+{
+    qCDebug(qLcEglfsKmsDebug, "Querying EGLDisplay");
+    EGLDisplay display;
+
+    PFNEGLGETPLATFORMDISPLAYEXTPROC getPlatformDisplay = nullptr;
+    const char *extensions = eglQueryString(EGL_NO_DISPLAY, EGL_EXTENSIONS);
+    if (extensions && (strstr(extensions, "EGL_KHR_platform_gbm") || strstr(extensions, "EGL_MESA_platform_gbm"))) {
+        getPlatformDisplay = reinterpret_cast<PFNEGLGETPLATFORMDISPLAYEXTPROC>(
+            eglGetProcAddress("eglGetPlatformDisplayEXT"));
+    }
+
+    if (getPlatformDisplay) {
+        display = getPlatformDisplay(EGL_PLATFORM_GBM_KHR, nativeDisplay, nullptr);
+    } else {
+        qCDebug(qLcEglfsKmsDebug, "No eglGetPlatformDisplay for GBM, falling back to eglGetDisplay");
+        display = eglGetDisplay(nativeDisplay);
+    }
+
+    return display;
+}
+
 EGLNativeWindowType QEglFSKmsGbmIntegration::createNativeWindow(QPlatformWindow *platformWindow,
                                                      const QSize &size,
                                                      const QSurfaceFormat &format)
diff --git a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmintegration.h b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmintegration.h
index 38f132d72e..e5b4f0c3b0 100644
--- a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmintegration.h
+++ b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmintegration.h
@@ -55,6 +55,7 @@ class QEglFSKmsGbmIntegration : public QEglFSKmsIntegration
 public:
     QEglFSKmsGbmIntegration();
 
+    EGLDisplay createDisplay(EGLNativeDisplayType nativeDisplay) override;
     EGLNativeWindowType createNativeWindow(QPlatformWindow *platformWindow,
                                            const QSize &size,
                                            const QSurfaceFormat &format) override;
diff --git a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms_support/qeglfskmsscreen.cpp b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms_support/qeglfskmsscreen.cpp
index 6920a81e94..6c8fffd8d9 100644
--- a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms_support/qeglfskmsscreen.cpp
+++ b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms_support/qeglfskmsscreen.cpp
@@ -69,7 +69,7 @@ private:
 };
 
 QEglFSKmsScreen::QEglFSKmsScreen(QKmsDevice *device, const QKmsOutput &output)
-    : QEglFSScreen(eglGetDisplay((EGLNativeDisplayType) device->nativeDisplay()))
+    : QEglFSScreen(static_cast<QEglFSIntegration *>(QGuiApplicationPrivate::platformIntegration())->display())
     , m_device(device)
     , m_output(output)
     , m_powerState(PowerStateOn)