Merge tag 'pwm/for-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry...

[sfrench/cifs-2.6.git] / Documentation / media / uapi / v4l / vidioc-reqbufs.rst

diff --git a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst
index 316f52c8a310b2c6f7fe3a4892b21035681af87a..d4bbbb0c60e80c94cadf94d928c60a0dcfec7adc 100644 (file)
--- a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst
+++ b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst
@@ -88,10 +88,50 @@ any DMA in progress, an implicit
        ``V4L2_MEMORY_DMABUF`` or ``V4L2_MEMORY_USERPTR``. See
        :c:type:`v4l2_memory`.
     * - __u32
-      - ``reserved``\ [2]
+      - ``capabilities``
+      - Set by the driver. If 0, then the driver doesn't support
+        capabilities. In that case all you know is that the driver is
+       guaranteed to support ``V4L2_MEMORY_MMAP`` and *might* support
+       other :c:type:`v4l2_memory` types. It will not support any others
+       capabilities.
+
+       If you want to query the capabilities with a minimum of side-effects,
+       then this can be called with ``count`` set to 0, ``memory`` set to
+       ``V4L2_MEMORY_MMAP`` and ``type`` set to the buffer type. This will
+       free any previously allocated buffers, so this is typically something
+       that will be done at the start of the application.
+    * - __u32
+      - ``reserved``\ [1]
       - A place holder for future extensions. Drivers and applications
        must set the array to zero.
 
+.. tabularcolumns:: |p{6.1cm}|p{2.2cm}|p{8.7cm}|
+
+.. _v4l2-buf-capabilities:
+.. _V4L2-BUF-CAP-SUPPORTS-MMAP:
+.. _V4L2-BUF-CAP-SUPPORTS-USERPTR:
+.. _V4L2-BUF-CAP-SUPPORTS-DMABUF:
+.. _V4L2-BUF-CAP-SUPPORTS-REQUESTS:
+
+.. cssclass:: longtable
+
+.. flat-table:: V4L2 Buffer Capabilities Flags
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       3 1 4
+
+    * - ``V4L2_BUF_CAP_SUPPORTS_MMAP``
+      - 0x00000001
+      - This buffer type supports the ``V4L2_MEMORY_MMAP`` streaming mode.
+    * - ``V4L2_BUF_CAP_SUPPORTS_USERPTR``
+      - 0x00000002
+      - This buffer type supports the ``V4L2_MEMORY_USERPTR`` streaming mode.
+    * - ``V4L2_BUF_CAP_SUPPORTS_DMABUF``
+      - 0x00000004
+      - This buffer type supports the ``V4L2_MEMORY_DMABUF`` streaming mode.
+    * - ``V4L2_BUF_CAP_SUPPORTS_REQUESTS``
+      - 0x00000008
+      - This buffer type supports :ref:`requests <media-request-api>`.
 
 Return Value
 ============