[PATCH 5/6] drm/msm: 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 msm's internal fbdev emulation. It
also simplifies the clean-up side of the fbdev emulation.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/msm/msm_fbdev.c | 55 +++++++++++++++++++--------------
 1 file changed, 32 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_fbdev.c b/drivers/gpu/drm/msm/msm_fbdev.c
index 5532c5779f17..f14db46aa51e 100644
--- a/drivers/gpu/drm/msm/msm_fbdev.c
+++ b/drivers/gpu/drm/msm/msm_fbdev.c
@@ -41,17 +41,15 @@ static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma)
 static void msm_fbdev_fb_destroy(struct fb_info *info)
 {
 	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
-	struct drm_framebuffer *fb = helper->fb;
-	struct drm_gem_object *bo = msm_framebuffer_bo(fb, 0);
+	struct drm_gem_object *bo = msm_framebuffer_bo(helper->fb, 0);
 
 	DBG();
 
 	drm_fb_helper_fini(helper);
 
-	/* this will free the backing object */
 	msm_gem_put_vaddr(bo);
-	drm_framebuffer_remove(fb);
 
+	drm_client_buffer_delete(helper->buffer);
 	drm_client_release(&helper->client);
 }
 
@@ -90,15 +88,16 @@ static const struct drm_fb_helper_funcs msm_fbdev_helper_funcs = {
 int msm_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 msm_drm_private *priv = dev->dev_private;
 	struct fb_info *fbi = helper->info;
-	struct drm_mode_fb_cmd2 mode_cmd = { };
-	struct drm_framebuffer *fb = NULL;
 	const struct drm_format_info *format;
-	u32 fourcc, pitch;
+	u32 fourcc, pitch, handle;
 	u64 size;
 	struct drm_gem_object *bo;
+	struct drm_client_buffer *buffer;
 	uint64_t paddr;
 	int ret;
 
@@ -127,16 +126,15 @@ int msm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 
 	msm_gem_object_set_name(bo, "stolenfb");
 
-	mode_cmd.pixel_format = fourcc;
-	mode_cmd.width = sizes->surface_width;
-	mode_cmd.height = sizes->surface_height;
-	mode_cmd.pitches[0] = pitch;
-
-	fb = msm_framebuffer_init(dev, format, &mode_cmd, &bo);
-	if (IS_ERR(fb)) {
-		drm_err(dev, "failed to allocate fb\n");
-		ret = PTR_ERR(fb);
+	ret = drm_gem_handle_create(file, bo, &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;
 	}
 
 	/*
@@ -147,13 +145,14 @@ int msm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 	ret = msm_gem_get_and_pin_iova(bo, priv->kms->vm, &paddr);
 	if (ret) {
 		drm_err(dev, "failed to get buffer obj iova: %d\n", ret);
-		goto err_drm_framebuffer_remove;
+		goto err_drm_client_buffer_delete;
 	}
 
 	DBG("fbi=%p, dev=%p", fbi, dev);
 
 	helper->funcs = &msm_fbdev_helper_funcs;
-	helper->fb = fb;
+	helper->buffer = buffer;
+	helper->fb = buffer->fb;
 
 	fbi->fbops = &msm_fb_ops;
 
@@ -162,19 +161,29 @@ int msm_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
 	fbi->screen_buffer = msm_gem_get_vaddr(bo);
 	if (IS_ERR(fbi->screen_buffer)) {
 		ret = PTR_ERR(fbi->screen_buffer);
-		goto err_drm_framebuffer_remove;
+		goto err_msm_gem_put_vaddr;
 	}
 	fbi->screen_size = bo->size;
 	fbi->fix.smem_start = paddr;
 	fbi->fix.smem_len = bo->size;
 
 	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
-	DBG("allocated %dx%d fb", fb->width, fb->height);
+	DBG("allocated %dx%d fb", buffer->fb->width, buffer->fb->height);
+
+	/* 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(bo);
 
 	return 0;
 
-err_drm_framebuffer_remove:
-	drm_framebuffer_remove(fb);
+err_msm_gem_put_vaddr:
+	msm_gem_put_vaddr(bo);
+err_drm_client_buffer_delete:
+	drm_client_buffer_delete(buffer);
+err_drm_gem_handle_delete:
+	drm_gem_handle_delete(file, handle);
 err_drm_gem_object_put:
 	drm_gem_object_put(bo);
 	return ret;
-- 
2.53.0