--- /dev/null
+From ebd995296afa99a5c53f164e595f7a6d41d32a01 Mon Sep 17 00:00:00 2001
+From: Hans Verkuil <hansverk@cisco.com>
+Date: Thu, 23 Aug 2018 09:56:22 -0400
+Subject: [PATCH] media: videodev2.h: add new capabilities for buffer
+ types
+
+Upstream commit f35f5d72e70e6b91389eb98fcabf43b79f40587f
+
+VIDIOC_REQBUFS and VIDIOC_CREATE_BUFFERS will return capabilities
+telling userspace what the given buffer type is capable of.
+
+Signed-off-by: Hans Verkuil <hansverk@cisco.com>
+Reviewed-by: Tomasz Figa <tfiga@chromium.org>
+Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
+Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
+---
+ .../media/uapi/v4l/vidioc-create-bufs.rst | 14 ++++++-
+ .../media/uapi/v4l/vidioc-reqbufs.rst | 42 ++++++++++++++++++-
+ include/uapi/linux/videodev2.h | 13 +++++-
+ 3 files changed, 65 insertions(+), 4 deletions(-)
+
+--- a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst
++++ b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst
+@@ -102,7 +102,19 @@ than the number requested.
+ - ``format``
+ - Filled in by the application, preserved by the driver.
+ * - __u32
+- - ``reserved``\ [8]
++ - ``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. See :ref:`here <v4l2-buf-capabilities>` for a list of the
++ capabilities.
++
++ If you want to just query the capabilities without making any
++ other changes, then set ``count`` to 0, ``memory`` to
++ ``V4L2_MEMORY_MMAP`` and ``format.type`` to the buffer type.
++ * - __u32
++ - ``reserved``\ [7]
+ - A place holder for future extensions. Drivers and applications
+ must set the array to zero.
+
+--- 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
+ ============
+--- a/include/uapi/linux/videodev2.h
++++ b/include/uapi/linux/videodev2.h
+@@ -872,9 +872,16 @@ struct v4l2_requestbuffers {
+ __u32 count;
+ __u32 type; /* enum v4l2_buf_type */
+ __u32 memory; /* enum v4l2_memory */
+- __u32 reserved[2];
++ __u32 capabilities;
++ __u32 reserved[1];
+ };
+
++/* capabilities for struct v4l2_requestbuffers and v4l2_create_buffers */
++#define V4L2_BUF_CAP_SUPPORTS_MMAP (1 << 0)
++#define V4L2_BUF_CAP_SUPPORTS_USERPTR (1 << 1)
++#define V4L2_BUF_CAP_SUPPORTS_DMABUF (1 << 2)
++#define V4L2_BUF_CAP_SUPPORTS_REQUESTS (1 << 3)
++
+ /**
+ * struct v4l2_plane - plane info for multi-planar buffers
+ * @bytesused: number of bytes occupied by data in the plane (payload)
+@@ -2318,6 +2325,7 @@ struct v4l2_dbg_chip_info {
+ * return: number of created buffers
+ * @memory: enum v4l2_memory; buffer memory type
+ * @format: frame format, for which buffers are requested
++ * @capabilities: capabilities of this buffer type.
+ * @reserved: future extensions
+ */
+ struct v4l2_create_buffers {
+@@ -2325,7 +2333,8 @@ struct v4l2_create_buffers {
+ __u32 count;
+ __u32 memory;
+ struct v4l2_format format;
+- __u32 reserved[8];
++ __u32 capabilities;
++ __u32 reserved[7];
+ };
+
+ /*
projects / openwrt / staging / dedeckeh.git / blobdiff