From 06f5531958dd5decaabb21c6fa1da3dcaf8dfc24 Mon Sep 17 00:00:00 2001 From: Benjamin Gaignard Date: Mon, 26 Aug 2024 17:24:09 +0000 Subject: [PATCH] media: videodev2: Add flag to unconditionally enumerate pixel formats When the index is ORed with V4L2_FMTDESC_FLAG_ENUM_ALL the driver clears the flag and enumerate all the possible formats, ignoring any limitations from the current configuration. Drivers which do not support this flag yet always return an EINVAL. Signed-off-by: Benjamin Gaignard Signed-off-by: Hans Verkuil [hverkuil: improved doc when the new flag is not supported by the driver] --- .../media/v4l/vidioc-enum-fmt.rst | 18 +++++++++++++++++- .../media/videodev2.h.rst.exceptions | 1 + include/uapi/linux/videodev2.h | 3 +++ 3 files changed, 21 insertions(+), 1 deletion(-) diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst index 3adb3d205531..0f69aa04607f 100644 --- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst +++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst @@ -85,7 +85,17 @@ the ``mbus_code`` field is handled differently: * - __u32 - ``index`` - Number of the format in the enumeration, set by the application. - This is in no way related to the ``pixelformat`` field. + This is in no way related to the ``pixelformat`` field. + When the index is ORed with ``V4L2_FMTDESC_FLAG_ENUM_ALL`` the + driver clears the flag and enumerates all the possible formats, + ignoring any limitations from the current configuration. Drivers + which do not support this flag always return an ``EINVAL`` + error code without clearing this flag. + Formats enumerated when using ``V4L2_FMTDESC_FLAG_ENUM_ALL`` flag + shouldn't be used when calling :c:func:`VIDIOC_ENUM_FRAMESIZES` + or :c:func:`VIDIOC_ENUM_FRAMEINTERVALS`. + ``V4L2_FMTDESC_FLAG_ENUM_ALL`` should only be used by drivers that + can return different format list depending on this flag. * - __u32 - ``type`` - Type of the data stream, set by the application. Only these types @@ -234,6 +244,12 @@ the ``mbus_code`` field is handled differently: valid. The buffer consists of ``height`` lines, each having ``width`` Data Units of data and the offset (in bytes) between the beginning of each two consecutive lines is ``bytesperline``. + * - ``V4L2_FMTDESC_FLAG_ENUM_ALL`` + - 0x80000000 + - When the applications ORs ``index`` with ``V4L2_FMTDESC_FLAG_ENUM_ALL`` flag + the driver enumerates all the possible pixel formats without taking care + of any already set configuration. Drivers which do not support this flag, + always return ``EINVAL`` without clearing this flag. Return Value ============ diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions index d67fd4038d22..429b5cdf05c3 100644 --- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions +++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions @@ -217,6 +217,7 @@ replace define V4L2_FMT_FLAG_CSC_YCBCR_ENC fmtdesc-flags replace define V4L2_FMT_FLAG_CSC_HSV_ENC fmtdesc-flags replace define V4L2_FMT_FLAG_CSC_QUANTIZATION fmtdesc-flags replace define V4L2_FMT_FLAG_META_LINE_BASED fmtdesc-flags +replace define V4L2_FMTDESC_FLAG_ENUM_ALL fmtdesc-flags # V4L2 timecode types replace define V4L2_TC_TYPE_24FPS timecode-type diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h index 21a8aa575ea3..ded023edac70 100644 --- a/include/uapi/linux/videodev2.h +++ b/include/uapi/linux/videodev2.h @@ -907,6 +907,9 @@ struct v4l2_fmtdesc { #define V4L2_FMT_FLAG_CSC_QUANTIZATION 0x0100 #define V4L2_FMT_FLAG_META_LINE_BASED 0x0200 +/* Format description flag, to be ORed with the index */ +#define V4L2_FMTDESC_FLAG_ENUM_ALL 0x80000000 + /* Frame Size and frame rate enumeration */ /* * F R A M E S I Z E E N U M E R A T I O N