Hi Shengjiu,
On 10/11/2023 06:48, Shengjiu Wang wrote:
> Audio signal processing has the requirement for memory to
> memory similar as Video.
>
> This patch is to add this support in v4l2 framework, defined
> new buffer type V4L2_BUF_TYPE_AUDIO_CAPTURE and
> V4L2_BUF_TYPE_AUDIO_OUTPUT, defined new format v4l2_audio_format
> for audio case usage.
>
> The created audio device is named "/dev/v4l-audioX".
>
> Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
> ---
> .../userspace-api/media/v4l/buffer.rst | 6 ++
> .../media/v4l/dev-audio-mem2mem.rst | 71 +++++++++++++++++++
> .../userspace-api/media/v4l/devices.rst | 1 +
> .../media/v4l/vidioc-enum-fmt.rst | 2 +
> .../userspace-api/media/v4l/vidioc-g-fmt.rst | 4 ++
> .../media/videodev2.h.rst.exceptions | 2 +
> .../media/common/videobuf2/videobuf2-v4l2.c | 4 ++
> drivers/media/v4l2-core/v4l2-dev.c | 17 +++++
> drivers/media/v4l2-core/v4l2-ioctl.c | 53 ++++++++++++++
> include/media/v4l2-dev.h | 2 +
> include/media/v4l2-ioctl.h | 34 +++++++++
> include/uapi/linux/videodev2.h | 17 +++++
> 12 files changed, 213 insertions(+)
> create mode 100644 Documentation/userspace-api/media/v4l/dev-audio-mem2mem.rst
While testing this patch series I discovered that you also need to patch
drivers/media/v4l2-core/v4l2-compat-ioctl32.c so it knows about the new
audio format.
Without that 32 bit apps will fail with a 64 bit kernel.
Regards,
Hans
>
> diff --git a/Documentation/userspace-api/media/v4l/buffer.rst b/Documentation/userspace-api/media/v4l/buffer.rst
> index 52bbee81c080..a3754ca6f0d6 100644
> --- a/Documentation/userspace-api/media/v4l/buffer.rst
> +++ b/Documentation/userspace-api/media/v4l/buffer.rst
> @@ -438,6 +438,12 @@ enum v4l2_buf_type
> * - ``V4L2_BUF_TYPE_META_OUTPUT``
> - 14
> - Buffer for metadata output, see :ref:`metadata`.
> + * - ``V4L2_BUF_TYPE_AUDIO_CAPTURE``
> + - 15
> + - Buffer for audio capture, see :ref:`audio`.
> + * - ``V4L2_BUF_TYPE_AUDIO_OUTPUT``
> + - 16
> + - Buffer for audio output, see :ref:`audio`.
>
>
> .. _buffer-flags:
> diff --git a/Documentation/userspace-api/media/v4l/dev-audio-mem2mem.rst b/Documentation/userspace-api/media/v4l/dev-audio-mem2mem.rst
> new file mode 100644
> index 000000000000..68faecfe3a02
> --- /dev/null
> +++ b/Documentation/userspace-api/media/v4l/dev-audio-mem2mem.rst
> @@ -0,0 +1,71 @@
> +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
> +
> +.. _audiomem2mem:
> +
> +********************************
> +Audio Memory-To-Memory Interface
> +********************************
> +
> +An audio memory-to-memory device can compress, decompress, transform, or
> +otherwise convert audio data from one format into another format, in memory.
> +Such memory-to-memory devices set the ``V4L2_CAP_AUDIO_M2M`` capability.
> +Examples of memory-to-memory devices are audio codecs, audio preprocessing,
> +audio postprocessing.
> +
> +A memory-to-memory audio node supports both output (sending audio frames from
> +memory to the hardware) and capture (receiving the processed audio frames
> +from the hardware into memory) stream I/O. An application will have to
> +setup the stream I/O for both sides and finally call
> +:ref:`VIDIOC_STREAMON <VIDIOC_STREAMON>` for both capture and output to
> +start the hardware.
> +
> +Memory-to-memory devices function as a shared resource: you can
> +open the audio node multiple times, each application setting up their
> +own properties that are local to the file handle, and each can use
> +it independently from the others. The driver will arbitrate access to
> +the hardware and reprogram it whenever another file handler gets access.
> +
> +Audio memory-to-memory devices are accessed through character device
> +special files named ``/dev/v4l-audio``
> +
> +Querying Capabilities
> +=====================
> +
> +Device nodes supporting the audio memory-to-memory interface set the
> +``V4L2_CAP_AUDIO_M2M`` flag in the ``device_caps`` field of the
> +:c:type:`v4l2_capability` structure returned by the :c:func:`VIDIOC_QUERYCAP`
> +ioctl.
> +
> +Data Format Negotiation
> +=======================
> +
> +The audio device uses the :ref:`format` ioctls to select the capture format.
> +The audio buffer content format is bound to that selected format. In addition
> +to the basic :ref:`format` ioctls, the :c:func:`VIDIOC_ENUM_FMT` ioctl must be
> +supported as well.
> +
> +To use the :ref:`format` ioctls applications set the ``type`` field of the
> +:c:type:`v4l2_format` structure to ``V4L2_BUF_TYPE_AUDIO_CAPTURE`` or to
> +``V4L2_BUF_TYPE_AUDIO_OUTPUT``. Both drivers and applications must set the
> +remainder of the :c:type:`v4l2_format` structure to 0.
> +
> +.. c:type:: v4l2_audio_format
> +
> +.. tabularcolumns:: |p{1.4cm}|p{2.4cm}|p{13.5cm}|
> +
> +.. flat-table:: struct v4l2_audio_format
> + :header-rows: 0
> + :stub-columns: 0
> + :widths: 1 1 2
> +
> + * - __u32
> + - ``pixelformat``
> + - The sample format, set by the application. see :ref:`pixfmt-audio`
> + * - __u32
> + - ``channels``
> + - The channel number, set by the application. channel number range is
> + [1, 32].
> + * - __u32
> + - ``buffersize``
> + - Maximum buffer size in bytes required for data. The value is set by the
> + driver.
> diff --git a/Documentation/userspace-api/media/v4l/devices.rst b/Documentation/userspace-api/media/v4l/devices.rst
> index 8bfbad65a9d4..758bd90f1c26 100644
> --- a/Documentation/userspace-api/media/v4l/devices.rst
> +++ b/Documentation/userspace-api/media/v4l/devices.rst
> @@ -24,3 +24,4 @@ Interfaces
> dev-event
> dev-subdev
> dev-meta
> + dev-audio-mem2mem
> diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
> index 000c154b0f98..42deb07f4ff4 100644
> --- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
> +++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
> @@ -96,6 +96,8 @@ the ``mbus_code`` field is handled differently:
> ``V4L2_BUF_TYPE_VIDEO_OVERLAY``,
> ``V4L2_BUF_TYPE_SDR_CAPTURE``,
> ``V4L2_BUF_TYPE_SDR_OUTPUT``,
> + ``V4L2_BUF_TYPE_AUDIO_CAPTURE``,
> + ``V4L2_BUF_TYPE_AUDIO_OUTPUT``,
> ``V4L2_BUF_TYPE_META_CAPTURE`` and
> ``V4L2_BUF_TYPE_META_OUTPUT``.
> See :c:type:`v4l2_buf_type`.
> diff --git a/Documentation/userspace-api/media/v4l/vidioc-g-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-g-fmt.rst
> index 675c385e5aca..528fd9df41aa 100644
> --- a/Documentation/userspace-api/media/v4l/vidioc-g-fmt.rst
> +++ b/Documentation/userspace-api/media/v4l/vidioc-g-fmt.rst
> @@ -130,6 +130,10 @@ The format as returned by :ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>` must be identical
> - ``meta``
> - Definition of a metadata format, see :ref:`meta-formats`, used by
> metadata capture devices.
> + * - struct :c:type:`v4l2_audio_format`
> + - ``audio``
> + - Definition of a audio data format, see :ref:`audiomem2mem`, used by
> + audio memory-to-memory devices
> * - __u8
> - ``raw_data``\ [200]
> - Place holder for future extensions.
> diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> index da6d0b8e4c2c..e61152bb80d1 100644
> --- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> +++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> @@ -29,6 +29,8 @@ replace symbol V4L2_FIELD_SEQ_TB :c:type:`v4l2_field`
> replace symbol V4L2_FIELD_TOP :c:type:`v4l2_field`
>
> # Documented enum v4l2_buf_type
> +replace symbol V4L2_BUF_TYPE_AUDIO_CAPTURE :c:type:`v4l2_buf_type`
> +replace symbol V4L2_BUF_TYPE_AUDIO_OUTPUT :c:type:`v4l2_buf_type`
> replace symbol V4L2_BUF_TYPE_META_CAPTURE :c:type:`v4l2_buf_type`
> replace symbol V4L2_BUF_TYPE_META_OUTPUT :c:type:`v4l2_buf_type`
> replace symbol V4L2_BUF_TYPE_SDR_CAPTURE :c:type:`v4l2_buf_type`
> diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
> index c7a54d82a55e..12f2be2773a2 100644
> --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
> +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
> @@ -785,6 +785,10 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
> case V4L2_BUF_TYPE_META_OUTPUT:
> requested_sizes[0] = f->fmt.meta.buffersize;
> break;
> + case V4L2_BUF_TYPE_AUDIO_CAPTURE:
> + case V4L2_BUF_TYPE_AUDIO_OUTPUT:
> + requested_sizes[0] = f->fmt.audio.buffersize;
> + break;
> default:
> return -EINVAL;
> }
> diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
> index f81279492682..b92c760b611a 100644
> --- a/drivers/media/v4l2-core/v4l2-dev.c
> +++ b/drivers/media/v4l2-core/v4l2-dev.c
> @@ -553,6 +553,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
> bool is_tch = vdev->vfl_type == VFL_TYPE_TOUCH;
> bool is_meta = vdev->vfl_type == VFL_TYPE_VIDEO &&
> (vdev->device_caps & meta_caps);
> + bool is_audio = vdev->vfl_type == VFL_TYPE_AUDIO;
> bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
> bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
> bool is_io_mc = vdev->device_caps & V4L2_CAP_IO_MC;
> @@ -664,6 +665,19 @@ static void determine_valid_ioctls(struct video_device *vdev)
> SET_VALID_IOCTL(ops, VIDIOC_S_FMT, vidioc_s_fmt_meta_out);
> SET_VALID_IOCTL(ops, VIDIOC_TRY_FMT, vidioc_try_fmt_meta_out);
> }
> + if (is_audio && is_rx) {
> + /* audio capture specific ioctls */
> + SET_VALID_IOCTL(ops, VIDIOC_ENUM_FMT, vidioc_enum_fmt_audio_cap);
> + SET_VALID_IOCTL(ops, VIDIOC_G_FMT, vidioc_g_fmt_audio_cap);
> + SET_VALID_IOCTL(ops, VIDIOC_S_FMT, vidioc_s_fmt_audio_cap);
> + SET_VALID_IOCTL(ops, VIDIOC_TRY_FMT, vidioc_try_fmt_audio_cap);
> + } else if (is_audio && is_tx) {
> + /* audio output specific ioctls */
> + SET_VALID_IOCTL(ops, VIDIOC_ENUM_FMT, vidioc_enum_fmt_audio_out);
> + SET_VALID_IOCTL(ops, VIDIOC_G_FMT, vidioc_g_fmt_audio_out);
> + SET_VALID_IOCTL(ops, VIDIOC_S_FMT, vidioc_s_fmt_audio_out);
> + SET_VALID_IOCTL(ops, VIDIOC_TRY_FMT, vidioc_try_fmt_audio_out);
> + }
> if (is_vbi) {
> /* vbi specific ioctls */
> if ((is_rx && (ops->vidioc_g_fmt_vbi_cap ||
> @@ -927,6 +941,9 @@ int __video_register_device(struct video_device *vdev,
> case VFL_TYPE_TOUCH:
> name_base = "v4l-touch";
> break;
> + case VFL_TYPE_AUDIO:
> + name_base = "v4l-audio";
> + break;
> default:
> pr_err("%s called with unknown type: %d\n",
> __func__, type);
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index 9b1de54ce379..1bb03794922a 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -188,6 +188,8 @@ const char *v4l2_type_names[] = {
> [V4L2_BUF_TYPE_SDR_OUTPUT] = "sdr-out",
> [V4L2_BUF_TYPE_META_CAPTURE] = "meta-cap",
> [V4L2_BUF_TYPE_META_OUTPUT] = "meta-out",
> + [V4L2_BUF_TYPE_AUDIO_CAPTURE] = "audio-cap",
> + [V4L2_BUF_TYPE_AUDIO_OUTPUT] = "audio-out",
> };
> EXPORT_SYMBOL(v4l2_type_names);
>
> @@ -276,6 +278,7 @@ static void v4l_print_format(const void *arg, bool write_only)
> const struct v4l2_sliced_vbi_format *sliced;
> const struct v4l2_window *win;
> const struct v4l2_meta_format *meta;
> + const struct v4l2_audio_format *audio;
> u32 pixelformat;
> u32 planes;
> unsigned i;
> @@ -346,6 +349,13 @@ static void v4l_print_format(const void *arg, bool write_only)
> pr_cont(", dataformat=%p4cc, buffersize=%u\n",
> &pixelformat, meta->buffersize);
> break;
> + case V4L2_BUF_TYPE_AUDIO_CAPTURE:
> + case V4L2_BUF_TYPE_AUDIO_OUTPUT:
> + audio = &p->fmt.audio;
> + pixelformat = audio->audioformat;
> + pr_cont(", format=%p4cc, channels=%u, buffersize=%u\n",
> + &pixelformat, audio->channels, audio->buffersize);
> + break;
> }
> }
>
> @@ -927,6 +937,7 @@ static int check_fmt(struct file *file, enum v4l2_buf_type type)
> bool is_tch = vfd->vfl_type == VFL_TYPE_TOUCH;
> bool is_meta = vfd->vfl_type == VFL_TYPE_VIDEO &&
> (vfd->device_caps & meta_caps);
> + bool is_audio = vfd->vfl_type == VFL_TYPE_AUDIO;
> bool is_rx = vfd->vfl_dir != VFL_DIR_TX;
> bool is_tx = vfd->vfl_dir != VFL_DIR_RX;
>
> @@ -992,6 +1003,14 @@ static int check_fmt(struct file *file, enum v4l2_buf_type type)
> if (is_meta && is_tx && ops->vidioc_g_fmt_meta_out)
> return 0;
> break;
> + case V4L2_BUF_TYPE_AUDIO_CAPTURE:
> + if (is_audio && is_rx && ops->vidioc_g_fmt_audio_cap)
> + return 0;
> + break;
> + case V4L2_BUF_TYPE_AUDIO_OUTPUT:
> + if (is_audio && is_tx && ops->vidioc_g_fmt_audio_out)
> + return 0;
> + break;
> default:
> break;
> }
> @@ -1597,6 +1616,16 @@ static int v4l_enum_fmt(const struct v4l2_ioctl_ops *ops,
> break;
> ret = ops->vidioc_enum_fmt_meta_out(file, fh, arg);
> break;
> + case V4L2_BUF_TYPE_AUDIO_CAPTURE:
> + if (unlikely(!ops->vidioc_enum_fmt_audio_cap))
> + break;
> + ret = ops->vidioc_enum_fmt_audio_cap(file, fh, arg);
> + break;
> + case V4L2_BUF_TYPE_AUDIO_OUTPUT:
> + if (unlikely(!ops->vidioc_enum_fmt_audio_out))
> + break;
> + ret = ops->vidioc_enum_fmt_audio_out(file, fh, arg);
> + break;
> }
> if (ret == 0)
> v4l_fill_fmtdesc(p);
> @@ -1673,6 +1702,10 @@ static int v4l_g_fmt(const struct v4l2_ioctl_ops *ops,
> return ops->vidioc_g_fmt_meta_cap(file, fh, arg);
> case V4L2_BUF_TYPE_META_OUTPUT:
> return ops->vidioc_g_fmt_meta_out(file, fh, arg);
> + case V4L2_BUF_TYPE_AUDIO_CAPTURE:
> + return ops->vidioc_g_fmt_audio_cap(file, fh, arg);
> + case V4L2_BUF_TYPE_AUDIO_OUTPUT:
> + return ops->vidioc_g_fmt_audio_out(file, fh, arg);
> }
> return -EINVAL;
> }
> @@ -1784,6 +1817,16 @@ static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,
> break;
> memset_after(p, 0, fmt.meta);
> return ops->vidioc_s_fmt_meta_out(file, fh, arg);
> + case V4L2_BUF_TYPE_AUDIO_CAPTURE:
> + if (unlikely(!ops->vidioc_s_fmt_audio_cap))
> + break;
> + memset_after(p, 0, fmt.audio);
> + return ops->vidioc_s_fmt_audio_cap(file, fh, arg);
> + case V4L2_BUF_TYPE_AUDIO_OUTPUT:
> + if (unlikely(!ops->vidioc_s_fmt_audio_out))
> + break;
> + memset_after(p, 0, fmt.audio);
> + return ops->vidioc_s_fmt_audio_out(file, fh, arg);
> }
> return -EINVAL;
> }
> @@ -1892,6 +1935,16 @@ static int v4l_try_fmt(const struct v4l2_ioctl_ops *ops,
> break;
> memset_after(p, 0, fmt.meta);
> return ops->vidioc_try_fmt_meta_out(file, fh, arg);
> + case V4L2_BUF_TYPE_AUDIO_CAPTURE:
> + if (unlikely(!ops->vidioc_try_fmt_audio_cap))
> + break;
> + memset_after(p, 0, fmt.audio);
> + return ops->vidioc_try_fmt_audio_cap(file, fh, arg);
> + case V4L2_BUF_TYPE_AUDIO_OUTPUT:
> + if (unlikely(!ops->vidioc_try_fmt_audio_out))
> + break;
> + memset_after(p, 0, fmt.audio);
> + return ops->vidioc_try_fmt_audio_out(file, fh, arg);
> }
> return -EINVAL;
> }
> diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h
> index d82dfdbf6e58..82b63f82d43f 100644
> --- a/include/media/v4l2-dev.h
> +++ b/include/media/v4l2-dev.h
> @@ -30,6 +30,7 @@
> * @VFL_TYPE_SUBDEV: for V4L2 subdevices
> * @VFL_TYPE_SDR: for Software Defined Radio tuners
> * @VFL_TYPE_TOUCH: for touch sensors
> + * @VFL_TYPE_AUDIO: for audio memory-to-memory devices
> * @VFL_TYPE_MAX: number of VFL types, must always be last in the enum
> */
> enum vfl_devnode_type {
> @@ -39,6 +40,7 @@ enum vfl_devnode_type {
> VFL_TYPE_SUBDEV,
> VFL_TYPE_SDR,
> VFL_TYPE_TOUCH,
> + VFL_TYPE_AUDIO,
> VFL_TYPE_MAX /* Shall be the last one */
> };
>
> diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
> index edb733f21604..f840cf740ce1 100644
> --- a/include/media/v4l2-ioctl.h
> +++ b/include/media/v4l2-ioctl.h
> @@ -45,6 +45,12 @@ struct v4l2_fh;
> * @vidioc_enum_fmt_meta_out: pointer to the function that implements
> * :ref:`VIDIOC_ENUM_FMT <vidioc_enum_fmt>` ioctl logic
> * for metadata output
> + * @vidioc_enum_fmt_audio_cap: pointer to the function that implements
> + * :ref:`VIDIOC_ENUM_FMT <vidioc_enum_fmt>` ioctl logic
> + * for audio capture
> + * @vidioc_enum_fmt_audio_out: pointer to the function that implements
> + * :ref:`VIDIOC_ENUM_FMT <vidioc_enum_fmt>` ioctl logic
> + * for audio output
> * @vidioc_g_fmt_vid_cap: pointer to the function that implements
> * :ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for video capture
> * in single plane mode
> @@ -79,6 +85,10 @@ struct v4l2_fh;
> * :ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for metadata capture
> * @vidioc_g_fmt_meta_out: pointer to the function that implements
> * :ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for metadata output
> + * @vidioc_g_fmt_audio_cap: pointer to the function that implements
> + * :ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for audio capture
> + * @vidioc_g_fmt_audio_out: pointer to the function that implements
> + * :ref:`VIDIOC_G_FMT <vidioc_g_fmt>` ioctl logic for audio output
> * @vidioc_s_fmt_vid_cap: pointer to the function that implements
> * :ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for video capture
> * in single plane mode
> @@ -113,6 +123,10 @@ struct v4l2_fh;
> * :ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for metadata capture
> * @vidioc_s_fmt_meta_out: pointer to the function that implements
> * :ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for metadata output
> + * @vidioc_s_fmt_audio_cap: pointer to the function that implements
> + * :ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for audio capture
> + * @vidioc_s_fmt_audio_out: pointer to the function that implements
> + * :ref:`VIDIOC_S_FMT <vidioc_g_fmt>` ioctl logic for audio output
> * @vidioc_try_fmt_vid_cap: pointer to the function that implements
> * :ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for video capture
> * in single plane mode
> @@ -149,6 +163,10 @@ struct v4l2_fh;
> * :ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for metadata capture
> * @vidioc_try_fmt_meta_out: pointer to the function that implements
> * :ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for metadata output
> + * @vidioc_try_fmt_audio_cap: pointer to the function that implements
> + * :ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for audio capture
> + * @vidioc_try_fmt_audio_out: pointer to the function that implements
> + * :ref:`VIDIOC_TRY_FMT <vidioc_g_fmt>` ioctl logic for audio output
> * @vidioc_reqbufs: pointer to the function that implements
> * :ref:`VIDIOC_REQBUFS <vidioc_reqbufs>` ioctl
> * @vidioc_querybuf: pointer to the function that implements
> @@ -315,6 +333,10 @@ struct v4l2_ioctl_ops {
> struct v4l2_fmtdesc *f);
> int (*vidioc_enum_fmt_meta_out)(struct file *file, void *fh,
> struct v4l2_fmtdesc *f);
> + int (*vidioc_enum_fmt_audio_cap)(struct file *file, void *fh,
> + struct v4l2_fmtdesc *f);
> + int (*vidioc_enum_fmt_audio_out)(struct file *file, void *fh,
> + struct v4l2_fmtdesc *f);
>
> /* VIDIOC_G_FMT handlers */
> int (*vidioc_g_fmt_vid_cap)(struct file *file, void *fh,
> @@ -345,6 +367,10 @@ struct v4l2_ioctl_ops {
> struct v4l2_format *f);
> int (*vidioc_g_fmt_meta_out)(struct file *file, void *fh,
> struct v4l2_format *f);
> + int (*vidioc_g_fmt_audio_cap)(struct file *file, void *fh,
> + struct v4l2_format *f);
> + int (*vidioc_g_fmt_audio_out)(struct file *file, void *fh,
> + struct v4l2_format *f);
>
> /* VIDIOC_S_FMT handlers */
> int (*vidioc_s_fmt_vid_cap)(struct file *file, void *fh,
> @@ -375,6 +401,10 @@ struct v4l2_ioctl_ops {
> struct v4l2_format *f);
> int (*vidioc_s_fmt_meta_out)(struct file *file, void *fh,
> struct v4l2_format *f);
> + int (*vidioc_s_fmt_audio_cap)(struct file *file, void *fh,
> + struct v4l2_format *f);
> + int (*vidioc_s_fmt_audio_out)(struct file *file, void *fh,
> + struct v4l2_format *f);
>
> /* VIDIOC_TRY_FMT handlers */
> int (*vidioc_try_fmt_vid_cap)(struct file *file, void *fh,
> @@ -405,6 +435,10 @@ struct v4l2_ioctl_ops {
> struct v4l2_format *f);
> int (*vidioc_try_fmt_meta_out)(struct file *file, void *fh,
> struct v4l2_format *f);
> + int (*vidioc_try_fmt_audio_cap)(struct file *file, void *fh,
> + struct v4l2_format *f);
> + int (*vidioc_try_fmt_audio_out)(struct file *file, void *fh,
> + struct v4l2_format *f);
>
> /* Buffer handlers */
> int (*vidioc_reqbufs)(struct file *file, void *fh,
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 5053f66c501a..1e06ac73b6fa 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -153,6 +153,8 @@ enum v4l2_buf_type {
> V4L2_BUF_TYPE_SDR_OUTPUT = 12,
> V4L2_BUF_TYPE_META_CAPTURE = 13,
> V4L2_BUF_TYPE_META_OUTPUT = 14,
> + V4L2_BUF_TYPE_AUDIO_CAPTURE = 15,
> + V4L2_BUF_TYPE_AUDIO_OUTPUT = 16,
> /* Deprecated, do not use */
> V4L2_BUF_TYPE_PRIVATE = 0x80,
> };
> @@ -169,6 +171,7 @@ enum v4l2_buf_type {
> || (type) == V4L2_BUF_TYPE_VBI_OUTPUT \
> || (type) == V4L2_BUF_TYPE_SLICED_VBI_OUTPUT \
> || (type) == V4L2_BUF_TYPE_SDR_OUTPUT \
> + || (type) == V4L2_BUF_TYPE_AUDIO_OUTPUT \
> || (type) == V4L2_BUF_TYPE_META_OUTPUT)
>
> #define V4L2_TYPE_IS_CAPTURE(type) (!V4L2_TYPE_IS_OUTPUT(type))
> @@ -2419,6 +2422,18 @@ struct v4l2_meta_format {
> __u32 buffersize;
> } __attribute__ ((packed));
>
> +/**
> + * struct v4l2_audio_format - audio data format definition
> + * @audioformat: little endian four character code (fourcc)
> + * @channels: channel numbers
> + * @buffersize: maximum size in bytes required for data
> + */
> +struct v4l2_audio_format {
> + __u32 audioformat;
> + __u32 channels;
> + __u32 buffersize;
> +} __attribute__ ((packed));
> +
> /**
> * struct v4l2_format - stream data format
> * @type: enum v4l2_buf_type; type of the data stream
> @@ -2427,6 +2442,7 @@ struct v4l2_meta_format {
> * @win: definition of an overlaid image
> * @vbi: raw VBI capture or output parameters
> * @sliced: sliced VBI capture or output parameters
> + * @audio: definition of an audio format
> * @raw_data: placeholder for future extensions and custom formats
> * @fmt: union of @pix, @pix_mp, @win, @vbi, @sliced, @sdr, @meta
> * and @raw_data
> @@ -2441,6 +2457,7 @@ struct v4l2_format {
> struct v4l2_sliced_vbi_format sliced; /* V4L2_BUF_TYPE_SLICED_VBI_CAPTURE */
> struct v4l2_sdr_format sdr; /* V4L2_BUF_TYPE_SDR_CAPTURE */
> struct v4l2_meta_format meta; /* V4L2_BUF_TYPE_META_CAPTURE */
> + struct v4l2_audio_format audio; /* V4L2_BUF_TYPE_AUDIO_CAPTURE */
> __u8 raw_data[200]; /* user-defined */
> } fmt;
> };
