drm_framebuffer_create_dumb() uses the dumb buffer API to create a buffer that is attached to a framebuffer. Useful for fbdev emulation.
Signed-off-by: Noralf Trønnes noralf@tronnes.org --- drivers/gpu/drm/drm_framebuffer.c | 61 +++++++++++++++++++++++++++++++++++++++ include/drm/drm_framebuffer.h | 4 +++ 2 files changed, 65 insertions(+)
diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c index af27984..07e5199 100644 --- a/drivers/gpu/drm/drm_framebuffer.c +++ b/drivers/gpu/drm/drm_framebuffer.c @@ -955,3 +955,64 @@ int drm_framebuffer_plane_height(int height, return fb_plane_height(height, fb->format, plane); } EXPORT_SYMBOL(drm_framebuffer_plane_height); + +/** + * drm_framebuffer_create_dumb - Create dumb framebuffer + * @file_priv: DRM file + * @width: Framebuffer width + * @height: Framebuffer height + * @format: Framebuffer FOURCC format + * + * This function creates a framebuffer backed by a dumb buffer for in-kernel + * use. fbdev emulation code can use this to create a framebuffer. + * + * Returns: + * Pointer to a drm_framebuffer on success or an error pointer on failure. + */ +struct drm_framebuffer * +drm_framebuffer_create_dumb(struct drm_file *file_priv, unsigned int width, + unsigned int height, u32 format) +{ + struct drm_device *dev = file_priv->minor->dev; + struct drm_mode_create_dumb dumb_args = { 0 }; + struct drm_mode_fb_cmd2 fb_args = { 0 }; + struct drm_framebuffer *fb; + int ret; + + dumb_args.width = width; + dumb_args.height = height; + dumb_args.bpp = drm_format_plane_cpp(format, 0) * 8; + + ret = drm_mode_create_dumb_ioctl(dev, &dumb_args, file_priv); + if (ret) + return ERR_PTR(ret); + + fb_args.width = width; + fb_args.height = height; + fb_args.pixel_format = format; + fb_args.handles[0] = dumb_args.handle; + fb_args.pitches[0] = dumb_args.pitch; + + ret = drm_mode_addfb2(dev, &fb_args, file_priv); + if (ret) + goto err_destroy_dumb; + + fb = drm_framebuffer_lookup(dev, fb_args.fb_id); + if (!fb) { + ret = -ENOENT; + goto err_rmfb; + } + + /* drop the reference we picked up in framebuffer lookup */ + drm_framebuffer_put(fb); + + return fb; + +err_rmfb: + drm_mode_rmfb(dev, &fb_args, file_priv); +err_destroy_dumb: + drm_mode_destroy_dumb_ioctl(dev, &dumb_args, file_priv); + + return ERR_PTR(ret); +} +EXPORT_SYMBOL(drm_framebuffer_create_dumb); diff --git a/include/drm/drm_framebuffer.h b/include/drm/drm_framebuffer.h index b6996dd..212c66a 100644 --- a/include/drm/drm_framebuffer.h +++ b/include/drm/drm_framebuffer.h @@ -306,4 +306,8 @@ int drm_framebuffer_plane_width(int width, int drm_framebuffer_plane_height(int height, const struct drm_framebuffer *fb, int plane);
+struct drm_framebuffer * +drm_framebuffer_create_dumb(struct drm_file *file_priv, unsigned int width, + unsigned int height, u32 format); + #endif