eglfs_kms: Add support for formats other than XRGB8888

Switch to drmModeAddFB2 and add mappings for RGB565 and ARGB8888,
and some BGR variants.

The default is XRGB8888, like before.

Others can be requested in the config file with
"format": "rgb565" or "argb8888" etc. on a per-output basis.

If the primary plane does not support the format, modesetting
and flipping will fail.

Task-number: QTBUG-62262
Change-Id: I8537cbeed7f046c46aa63fcea6d6946c0e0038a7
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
Reviewed-by: Andy Nichols <andy.nichols@qt.io>

2 files changed, 32 insertions, 1 deletions

diff --git a/src/platformsupport/kmsconvenience/qkmsdevice.cpp b/src/platformsupport/kmsconvenience/qkmsdevice.cpp
index e2a478bf03..c1edd384fe 100644
--- a/src/platformsupport/kmsconvenience/qkmsdevice.cpp
+++ b/src/platformsupport/kmsconvenience/qkmsdevice.cpp
@@ -324,6 +324,34 @@ QPlatformScreen *QKmsDevice::createScreenForConnector(drmModeResPtr resources,
     }
     qCDebug(qLcKmsDebug) << "Physical size is" << physSize << "mm" << "for output" << connectorName;
 
+    const QByteArray formatStr = userConnectorConfig.value(QStringLiteral("format"), QStringLiteral("xrgb8888"))
+            .toByteArray().toLower();
+    uint32_t drmFormat;
+    if (formatStr == "xrgb8888") {
+        drmFormat = DRM_FORMAT_XRGB8888;
+    } else if (formatStr == "xbgr8888") {
+        drmFormat = DRM_FORMAT_XBGR8888;
+    } else if (formatStr == "argb8888") {
+        drmFormat = DRM_FORMAT_ARGB8888;
+    } else if (formatStr == "abgr8888") {
+        drmFormat = DRM_FORMAT_ABGR8888;
+    } else if (formatStr == "rgb565") {
+        drmFormat = DRM_FORMAT_RGB565;
+    } else if (formatStr == "bgr565") {
+        drmFormat = DRM_FORMAT_BGR565;
+    } else if (formatStr == "xrgb2101010") {
+        drmFormat = DRM_FORMAT_XRGB2101010;
+    } else if (formatStr == "xbgr2101010") {
+        drmFormat = DRM_FORMAT_XBGR2101010;
+    } else if (formatStr == "argb2101010") {
+        drmFormat = DRM_FORMAT_ARGB2101010;
+    } else if (formatStr == "abgr2101010") {
+        drmFormat = DRM_FORMAT_ABGR2101010;
+    } else {
+        qWarning("Invalid pixel format \"%s\" for output %s", formatStr.constData(), connectorName.constData());
+        drmFormat = DRM_FORMAT_XRGB8888;
+    }
+
     QKmsOutput output = {
         QString::fromUtf8(connectorName),
         connector->connector_id,
@@ -339,7 +367,8 @@ QPlatformScreen *QKmsDevice::createScreenForConnector(drmModeResPtr resources,
         connectorPropertyBlob(connector, QByteArrayLiteral("EDID")),
         false, // wants_plane
         0, // plane_id
-        false // plane_set
+        false, // plane_set
+        drmFormat
     };
 
     bool ok;
diff --git a/src/platformsupport/kmsconvenience/qkmsdevice_p.h b/src/platformsupport/kmsconvenience/qkmsdevice_p.h
index 964a0b1775..c33a958f4c 100644
--- a/src/platformsupport/kmsconvenience/qkmsdevice_p.h
+++ b/src/platformsupport/kmsconvenience/qkmsdevice_p.h
@@ -59,6 +59,7 @@
 
 #include <xf86drm.h>
 #include <xf86drmMode.h>
+#include <drm_fourcc.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -111,6 +112,7 @@ struct QKmsOutput
     bool wants_plane;
     uint32_t plane_id;
     bool plane_set;
+    uint32_t drm_format;
 
     void restoreMode(QKmsDevice *device);
     void cleanup(QKmsDevice *device);