Re: [PATCH v12 07/15] media: v4l2: Add audio capture and output support

On 17/02/2024 10:42, Mauro Carvalho Chehab wrote:

Em Thu, 18 Jan 2024 20:32:00 +0800 Shengjiu Wang shengjiu.wang@nxp.com 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@nxp.com

.../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

...

•  - 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

Ah, that's a doc bug: this field is called audioformat in the struct, not pixelformat. I missed this one in my review.

Regards,

Hans

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?

...

• • • __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.

...

• • @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