Hi Mauro, Hans
On Sat, Feb 17, 2024 at 5:42 PM Mauro Carvalho Chehab
<mchehab@xxxxxxxxxx> wrote:
>
> Em Thu, 18 Jan 2024 20:32:00 +0800
> Shengjiu Wang <shengjiu.wang@xxxxxxx> escreveu:
>
> > 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-compat-ioctl32.c | 9 +++
> > 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 +++++
> > 13 files changed, 222 insertions(+)
> > create mode 100644 Documentation/userspace-api/media/v4l/dev-audio-mem2mem.rst
> >
> > 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
>
> Hmm... alsa APi define input/output as:
> enum {
> SNDRV_PCM_STREAM_PLAYBACK = 0,
> SNDRV_PCM_STREAM_CAPTURE,
> SNDRV_PCM_STREAM_LAST = SNDRV_PCM_STREAM_CAPTURE,
> };
>
>
> I would use a namespace as close as possible to the
> ALSA API. Also, we're not talking about V4L2, but, instead
> audio. so, not sure if I like the prefix to start with
> V4L2_. Maybe ALSA_?
>
> So, a better namespace would be:
>
> ${prefix}_BUF_TYPE_PCM_STREAM_PLAYBACK
> and
> ${prefix}_BUF_TYPE_PCM_STREAM_CAPTURE
>
Ok, So can I use the name below?
V4L2_BUF_TYPE_PCM_STREAM_PLAYBACK
V4L2_BUF_TYPE_PCM_STREAM_CAPTURE
> > + - 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`
>
> pixelformat doesn't make any sense for audio: there are no pixels on a
> PCM stream. Please use call it, instead: `snd_pcm_format`, making it match
> the values for snd_pcm_format_t.
>
> Yet, I would keep defining it as u32 (or u64?) instead of using a
> typedef int field there (snd_pcm_format_t), as the size of integer
> is different on 32 and 64 bit kernels.
>
>
> > + * - __u32
> > + - ``channels``
> > + - The channel number, set by the application. channel number range is
> > + [1, 32].
>
> Why not start on zero?
channels in audio are at least 1.
>
> > + * - __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 54d572c3b515..16ab204d15b0 100644
> > --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
> > +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
> > @@ -791,6 +791,10 @@ 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-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
> > index 8c07400bd280..5e94db8dfdae 100644
> > --- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
> > +++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c
> > @@ -101,6 +101,7 @@ struct v4l2_format32 {
> > struct v4l2_sliced_vbi_format sliced;
> > struct v4l2_sdr_format sdr;
> > struct v4l2_meta_format meta;
> > + struct v4l2_audio_format audio;
> > __u8 raw_data[200]; /* user-defined */
> > } fmt;
> > };
> > @@ -166,6 +167,10 @@ static int get_v4l2_format32(struct v4l2_format *p64,
> > case V4L2_BUF_TYPE_META_OUTPUT:
> > return copy_from_user(&p64->fmt.meta, &p32->fmt.meta,
> > sizeof(p64->fmt.meta)) ? -EFAULT : 0;
> > + case V4L2_BUF_TYPE_AUDIO_CAPTURE:
> > + case V4L2_BUF_TYPE_AUDIO_OUTPUT:
> > + return copy_from_user(&p64->fmt.audio, &p32->fmt.audio,
> > + sizeof(p64->fmt.audio)) ? -EFAULT : 0;
> > default:
> > return -EINVAL;
> > }
> > @@ -216,6 +221,10 @@ static int put_v4l2_format32(struct v4l2_format *p64,
> > case V4L2_BUF_TYPE_META_OUTPUT:
> > return copy_to_user(&p32->fmt.meta, &p64->fmt.meta,
> > sizeof(p64->fmt.meta)) ? -EFAULT : 0;
> > + case V4L2_BUF_TYPE_AUDIO_CAPTURE:
> > + case V4L2_BUF_TYPE_AUDIO_OUTPUT:
> > + return copy_to_user(&p32->fmt.audio, &p64->fmt.audio,
> > + sizeof(p64->fmt.audio)) ? -EFAULT : 0;
> > default:
> > return -EINVAL;
> > }
> > diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
> > index d13954bd31fd..bac008fcedc6 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;
> > @@ -666,6 +667,19 @@ 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 ||
> > @@ -929,6 +943,9 @@ 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 33076af4dfdb..e7be7c2f302d 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 6cd65969c2b5..57c82eb158f1 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))
> > @@ -2423,6 +2426,18 @@ struct v4l2_meta_format {
> > __u32 buffersize;
> > } __attribute__ ((packed));
> >
> > +/**
> > + * struct v4l2_audio_format - audio data format definition
> > + * @audioformat: little endian four character code (fourcc)
>
> Don't use fourcc here. Instead, use the types defined at snd_pcm_format_t.
In the earlier version of this patch series, fourcc is not used in this
struct v4l2_audio_format.
I use "__u32 audioformat", the value is from snd_pcm_format_t.
Using "__u32" is in order to avoid including the include/uapi/sound/asound.h
header.
And defined V4L2_AUDIO_FMT_LPCM for the v4l2_fmtdesc.pixelformat
#define V4L2_AUDIO_FMT_LPCM v4l2_fourcc('L', 'P', 'C', 'M') /*
audio lpcm */
After discussing with Hans, I use the current way for v4l audio.
Hans:
Not sure if you can accept going back to the previous solution?
You have already done similar changes in v4l-utils.
Best regards
Shengjiu Wang
>
> > + * @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
> > @@ -2431,6 +2446,7 @@ 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
> > @@ -2445,6 +2461,7 @@ 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;
> > };
>
>
>
> Thanks,
> Mauro
