[PATCH v3 4/5] drm/exynos: fbdev: Use a DRM client buffer

[Thomas Zimmermann <tzimmermann@suse.de>]

Replace the internal DRM framebuffer with a DRM client buffer. The
client buffer allocates the DRM framebuffer on a file and also uses
GEM object handles via the regular ADDFB2 interfaces.

Using client-buffer interfaces unifies framebuffer allocation for
DRM clients in user space and exynos' internal fbdev emulation. It
also simplifies the clean-up side of the fbdev emulation.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 drivers/gpu/drm/exynos/exynos_drm_fbdev.c | 46 ++++++++++++++---------
 1 file changed, 28 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
index 9163efd676dd..121c342dd14a 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
@@ -36,12 +36,10 @@ static int exynos_drm_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 static void exynos_drm_fb_destroy(struct fb_info *info)
 {
 	struct drm_fb_helper *fb_helper = info->par;
-	struct drm_framebuffer *fb = fb_helper->fb;
 
 	drm_fb_helper_fini(fb_helper);
 
-	drm_framebuffer_remove(fb);
-
+	drm_client_buffer_delete(fb_helper->buffer);
 	drm_client_release(&fb_helper->client);
 }
 
@@ -60,14 +58,17 @@ static const struct drm_fb_helper_funcs exynos_drm_fbdev_helper_funcs = {
 int exynos_drm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 					struct drm_fb_helper_surface_size *sizes)
 {
-	struct drm_device *dev = helper->dev;
+	struct drm_client_dev *client = &helper->client;
+	struct drm_device *dev = client->dev;
+	struct drm_file *file = client->file;
 	struct fb_info *info = helper->info;
 	u32 fourcc, pitch;
 	u64 size;
 	const struct drm_format_info *format;
 	struct exynos_drm_gem *exynos_gem;
 	struct drm_gem_object *obj;
-	struct drm_mode_fb_cmd2 mode_cmd = { 0 };
+	struct drm_client_buffer *buffer;
+	u32 handle;
 	int ret;
 
 	DRM_DEV_DEBUG_KMS(dev->dev,
@@ -95,19 +96,20 @@ int exynos_drm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 		return PTR_ERR(exynos_gem);
 	obj = &exynos_gem->base;
 
-	mode_cmd.width = sizes->surface_width;
-	mode_cmd.height = sizes->surface_height;
-	mode_cmd.pixel_format = fourcc;
-	mode_cmd.pitches[0] = pitch;
-	mode_cmd.modifier[0] = DRM_FORMAT_MOD_LINEAR;
-
-	helper->fb = exynos_drm_framebuffer_init(dev, format, &mode_cmd, &exynos_gem, 1);
-	if (IS_ERR(helper->fb)) {
-		DRM_DEV_ERROR(dev->dev, "failed to create drm framebuffer.\n");
-		ret = PTR_ERR(helper->fb);
-		goto err_destroy_gem;
+	ret = drm_gem_handle_create(file, obj, &handle);
+	if (ret)
+		goto err_drm_gem_object_put;
+
+	buffer = drm_client_buffer_create(client, sizes->surface_width, sizes->surface_height,
+					  fourcc, handle, pitch);
+	if (IS_ERR(buffer)) {
+		ret = PTR_ERR(buffer);
+		goto err_drm_gem_handle_delete;
 	}
+
 	helper->funcs = &exynos_drm_fbdev_helper_funcs;
+	helper->buffer = buffer;
+	helper->fb = buffer->fb;
 
 	info->fbops = &exynos_drm_fb_ops;
 
@@ -118,9 +120,17 @@ int exynos_drm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 	info->screen_size = obj->size;
 	info->fix.smem_len = obj->size;
 
+	/* The handle is only needed for creating the framebuffer. */
+	drm_gem_handle_delete(file, handle);
+
+	/* The framebuffer still holds a reference on the GEM object. */
+	drm_gem_object_put(obj);
+
 	return 0;
 
-err_destroy_gem:
-	exynos_drm_gem_destroy(exynos_gem);
+err_drm_gem_handle_delete:
+	drm_gem_handle_delete(file, handle);
+err_drm_gem_object_put:
+	drm_gem_object_put(obj);
 	return ret;
 }
-- 
2.54.0