Hi Shengjiu, On Tue, Jul 25, 2023 at 02:12:17PM +0800, 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/audioX". > > Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx> > --- > .../media/common/videobuf2/videobuf2-v4l2.c | 4 ++ > drivers/media/v4l2-core/v4l2-dev.c | 17 ++++++ > drivers/media/v4l2-core/v4l2-ioctl.c | 52 +++++++++++++++++++ > include/media/v4l2-dev.h | 2 + > include/media/v4l2-ioctl.h | 34 ++++++++++++ > include/uapi/linux/videodev2.h | 19 +++++++ > 6 files changed, 128 insertions(+) > Thanks for the patch! Please check my comments inline. > 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..67484f4c6eaf 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 = "audio"; I think it was mentioned before that "audio" could be confusing. Wasn't there actually some other kind of /dev/audio device long ago? Seems like for touch, "v4l-touch" was introduced. Maybe it would also make sense to call it "v4l-audio" for 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 01ba27f2ef87..aa9d872bba8d 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 +349,12 @@ 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; > + pr_cont(", rate=%u, format=%u, channels=%u, buffersize=%u\n", > + audio->rate, audio->format, audio->channels, audio->buffersize); > + break; > } > } > > @@ -927,6 +936,7 @@ 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 +1002,14 @@ 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; > } > @@ -1594,6 +1612,16 @@ 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); > @@ -1670,6 +1698,10 @@ 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; > } > @@ -1781,6 +1813,16 @@ 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; > } > @@ -1889,6 +1931,16 @@ 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 e0a13505f88d..0924e6d1dab1 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 input/output 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 3af6a82d0cad..e5051410928a 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)) > @@ -2415,6 +2418,20 @@ struct v4l2_meta_format { > __u32 buffersize; > } __attribute__ ((packed)); > > +/** > + * struct v4l2_audio_format - audio data format definition > + * @rate: sample rate > + * @format: sample format > + * @channels: channel numbers > + * @buffersize: maximum size in bytes required for data > + */ > +struct v4l2_audio_format { > + __u32 rate; > + __u32 format; What are the values for the rate and format fields? Since they are part of the UAPI, they need to be defined. Best regards, Tomasz > + __u32 channels; > + __u32 buffersize; > +} __attribute__ ((packed)); > + > /** > * struct v4l2_format - stream data format > * @type: enum v4l2_buf_type; type of the data stream > @@ -2423,6 +2440,7 @@ 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 > @@ -2437,6 +2455,7 @@ 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; > }; > -- > 2.34.1 >