diff options
| author | Chia-I Wu <olvaffe@gmail.com> | 2019-04-17 09:40:19 -0700 |
|---|---|---|
| committer | Daniel Stone <daniels@collabora.com> | 2019-05-02 12:30:32 +0100 |
| commit | fb9b2a87317c77e26283da5f6c9559d709f6fdcd (patch) | |
| tree | 2518f0c1daf914ab6b8eb50146ad8dbe60a87d78 | |
| parent | 70ed9d7ee8f6491032fcccb74f25693851d740f2 (diff) | |
linux-dmabuf: clarify DRM_FORMAT_MOD_INVALID
DRM_FORMAT_MOD_INVALID means to derive the modifier from the dmabuf.
It provides legacy support and makes it easier to replace wl_drm.
v3: DRM_FORMAT_MOD_INVALID must be advertised to be supported (which
requires a version bump)
v4: no version bump, but a note for now
Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Reviewed-by: Simon Ser <contact@emersion.fr>
Reviewed-by: Daniel Stone <daniels@collabora.com>
| -rw-r--r-- | unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml b/unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml index 154afe2..b43e81c 100644 --- a/unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml +++ b/unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml @@ -28,6 +28,7 @@ <description summary="factory for creating dmabuf-based wl_buffers"> Following the interfaces from: https://www.khronos.org/registry/egl/extensions/EXT/EGL_EXT_image_dma_buf_import.txt + https://www.khronos.org/registry/EGL/extensions/EXT/EGL_EXT_image_dma_buf_import_modifiers.txt and the Linux DRM sub-system's AddFb2 ioctl. This interface offers ways to create generic dmabuf-based @@ -129,8 +130,16 @@ binds to this interface. A roundtrip after binding guarantees that the client has received all supported format-modifier pairs. + For legacy support, DRM_FORMAT_MOD_INVALID (that is, modifier_hi == + 0x00ffffff and modifier_lo == 0xffffffff) is allowed in this event. + It indicates that the server can support the format with an implicit + modifier. When a plane has DRM_FORMAT_MOD_INVALID as its modifier, it + is as if no explicit modifier is specified. The effective modifier + will be derived from the dmabuf. + For the definition of the format and modifier codes, see the - zwp_linux_buffer_params_v1::create request. + zwp_linux_buffer_params_v1::create and zwp_linux_buffer_params_v1::add + requests. </description> <arg name="format" type="uint" summary="DRM_FORMAT code"/> <arg name="modifier_hi" type="uint" @@ -197,6 +206,11 @@ compression, etc. driver-specific modifications to the base format defined by the DRM fourcc code. + Warning: It should be an error if the format/modifier pair was not + advertised with the modifier event. This is not enforced yet because + some implementations always accept DRM_FORMAT_MOD_INVALID. Also + version 2 of this protocol does not have the modifier event. + This request raises the PLANE_IDX error if plane_idx is too large. The error PLANE_SET is raised if attempting to set a plane that was already set. |