drm/mediatek: Run DRM default client setup

Call drm_client_setup() to run the kernel's default client setup
for DRM. Set fbdev_probe in struct drm_driver, so that the client
setup can start the common fbdev client.

The mediatek driver specifies a preferred color mode of 32. As this
is the default if no format has been given, leave it out entirely.

v5:
- select DRM_CLIENT_SELECTION

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Chun-KuaIng Hu <chunkuang.hu@kernel.org>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240924071734.98201-27-tzimmermann@suse.de

drivers/gpu/drm/mediatek/Kconfig

@@ -7,6 +7,7 @@ config DRM_MEDIATEK
 	depends on HAVE_ARM_SMCCC
 	depends on OF
 	depends on MTK_MMSYS
+	select DRM_CLIENT_SELECTION
 	select DRM_GEM_DMA_HELPER if DRM_FBDEV_EMULATION
 	select DRM_KMS_HELPER
 	select DRM_DISPLAY_HELPER

drivers/gpu/drm/mediatek/mtk_drm_drv.c

@@ -14,6 +14,7 @@
 
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_client_setup.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_fbdev_dma.h>
 #include <drm/drm_fourcc.h>
@@ -610,6 +611,7 @@ static const struct drm_driver mtk_drm_driver = {
 	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
 
 	.dumb_create = mtk_gem_dumb_create,
+	DRM_FBDEV_DMA_DRIVER_OPS,
 
 	.gem_prime_import = mtk_gem_prime_import,
 	.gem_prime_import_sg_table = mtk_gem_prime_import_sg_table,
@@ -666,7 +668,7 @@ static int mtk_drm_bind(struct device *dev)
 	if (ret < 0)
 		goto err_deinit;
 
-	drm_fbdev_dma_setup(drm, 32);
+	drm_client_setup(drm, NULL);
 
 	return 0;