[PATCH v4,04/22] v4l: add documentation for restricted memory flag

From: Yunfei Dong
Date: Mon Jan 29 2024 - 01:31:17 EST


From: Jeffrey Kardatzke <jkardatzke@xxxxxxxxxx>

Adds documentation for V4L2_MEMORY_FLAG_RESTRICTED.

Signed-off-by: Jeffrey Kardatzke <jkardatzke@xxxxxxxxxx>
Signed-off-by: Yunfei Dong <yunfei.dong@xxxxxxxxxxxx>
---
Documentation/userspace-api/media/v4l/buffer.rst | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/Documentation/userspace-api/media/v4l/buffer.rst b/Documentation/userspace-api/media/v4l/buffer.rst
index 52bbee81c080..807e43bfed2b 100644
--- a/Documentation/userspace-api/media/v4l/buffer.rst
+++ b/Documentation/userspace-api/media/v4l/buffer.rst
@@ -696,7 +696,7 @@ enum v4l2_memory

.. _memory-flags:

-Memory Consistency Flags
+Memory Flags
------------------------

.. raw:: latex
@@ -728,6 +728,14 @@ Memory Consistency Flags
only if the buffer is used for :ref:`memory mapping <mmap>` I/O and the
queue reports the :ref:`V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS
<V4L2-BUF-CAP-SUPPORTS-MMAP-CACHE-HINTS>` capability.
+ * .. _`V4L2-MEMORY-FLAG-RESTRICTED`:
+
+ - ``V4L2_MEMORY_FLAG_RESTRICTED``
+ - 0x00000002
+ - The queued buffers are expected to be in restricted memory. If not, an
+ error will be returned. This flag can only be used with ``V4L2_MEMORY_DMABUF``.
+ Typically restricted buffers are allocated using a restricted dma-heap. This flag
+ can only be specified if the ``V4L2_BUF_CAP_SUPPORTS_RESTRICTED_MEM`` is set.

.. raw:: latex

--
2.18.0