Re: [PATCH v12 08/15] media: uapi: Define audio sample format fourcc type

2024-02-23 Thread Hans Verkuil 
On 22/02/2024 04:50, Shengjiu Wang wrote:
> On Wed, Feb 21, 2024 at 7:10 PM Hans Verkuil  wrote:
>>
>> On 19/02/2024 13:56, Mauro Carvalho Chehab wrote:
>>> Em Mon, 19 Feb 2024 12:05:02 +0800
>>> Shengjiu Wang  escreveu:
>>>
 Hi Mauro

 On Sat, Feb 17, 2024 at 5:19 PM Mauro Carvalho Chehab
  wrote:
>
> Em Thu, 18 Jan 2024 20:32:01 +0800
> Shengjiu Wang  escreveu:
>
>> The audio sample format definition is from alsa,
>> the header file is include/uapi/sound/asound.h, but
>> don't include this header file directly, because in
>> user space, there is another copy in alsa-lib.
>> There will be conflict in userspace for include
>> videodev2.h & asound.h and asoundlib.h
>>
>> Here still use the fourcc format.
>>
>> Signed-off-by: Shengjiu Wang 
>> ---
>>  .../userspace-api/media/v4l/pixfmt-audio.rst  | 87 +++
>>  .../userspace-api/media/v4l/pixfmt.rst|  1 +
>>  drivers/media/v4l2-core/v4l2-ioctl.c  | 13 +++
>>  include/uapi/linux/videodev2.h| 23 +
>>  4 files changed, 124 insertions(+)
>>  create mode 100644 
>> Documentation/userspace-api/media/v4l/pixfmt-audio.rst
>>
>> diff --git a/Documentation/userspace-api/media/v4l/pixfmt-audio.rst 
>> b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
>> new file mode 100644
>> index ..04b4a7fbd8f4
>> --- /dev/null
>> +++ b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
>> @@ -0,0 +1,87 @@
>> +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
>> +
>> +.. _pixfmt-audio:
>> +
>> +*
>> +Audio Formats
>> +*
>> +
>> +These formats are used for :ref:`audiomem2mem` interface only.
>> +
>> +.. tabularcolumns:: |p{5.8cm}|p{1.2cm}|p{10.3cm}|
>> +
>> +.. cssclass:: longtable
>> +
>> +.. flat-table:: Audio Format
>> +:header-rows:  1
>> +:stub-columns: 0
>> +:widths:   3 1 4
>> +
>> +* - Identifier
>> +  - Code
>> +  - Details
>> +* .. _V4L2-AUDIO-FMT-S8:
>> +
>> +  - ``V4L2_AUDIO_FMT_S8``
>> +  - 'S8'
>> +  - Corresponds to SNDRV_PCM_FORMAT_S8 in ALSA
>> +* .. _V4L2-AUDIO-FMT-S16-LE:
>
> Hmm... why can't we just use SNDRV_*_FORMAT_*? Those are already part of
> an uAPI header. No need to add any abstraction here and/or redefine
> what is there already at include/uapi/sound/asound.h.
>
 Actually I try to avoid including the include/uapi/sound/asound.h.
 Because in user space, there is another copy in alsa-lib (asoundlib.h).
 There will be conflict in userspace when including videodev2.h and
 asoundlib.h.
>>>
>>> Well, alsasoundlib.h seems to be using the same definitions:
>>>   https://github.com/michaelwu/alsa-lib/blob/master/include/pcm.h
>>>
>>> So, I can't see what would be the actual issue, as both userspace library
>>> and ALSA internal headers use the same magic numbers.
>>>
>>> You can still do things like:
>>>
>>>   #ifdef __KERNEL__
>>>   #  include 
>>>   #else
>>>   #  include 
>>>   #endif
>>>
>>> To avoid such kind of conflicts, if you need to have it included on
>>> some header file. Yet, I can't see why you would need that.
>>>
>>> IMO, at uAPI headers, you just need to declare the uAPI audiofmt field
>>> to be either __u32 or __u64, pointing it to where this value comes from
>>> (on both userspace and Kernelspace. E. g.:
>>>
>>> /**
>>>  * struct v4l2_audio_format - audio data format definition
>>>  * @audioformat:
>>>  *an integer number matching the fields inside
>>>  *enum snd_pcm_format_t (e. g. `SNDRV_PCM_FORMAT_*`), as defined
>>>  *in include/uapi/sound/asound.h and
>>>  *  
>>> https://www.alsa-project.org/alsa-doc/alsa-lib/group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8.
>>>  * @channels: channel numbers
>>>  * @buffersize:   maximum size in bytes required for data
>>>  */
>>> struct v4l2_audio_format {
>>>   __u32   audioformat;
>>>   __u32   channels;
>>>   __u32   buffersize;
>>> } __attribute__ ((packed));
>>>
>>> Then, at documentation you just need to point to where the
>>> possible values for SNDRV_PCM_FORMAT_ are defined. No need to
>>> document them one by one.
>>>
>>> With such definition, you'll only need to include sound/asound.h
>>> within the kAPI scope.
>>>

 And in the V4l framework, the fourcc type is commonly used in other
 cases (video, radio, touch, meta), to avoid changing common code
 a lot, so I think using fourcc definition for audio may be simpler.
>>>
>>> Those are real video streams (or a video-related streams, in the case
>>> of metadata) where fourcc is widely used. There, it makes sense.
>>> However, ALSA format definitions

Re: [PATCH v12 08/15] media: uapi: Define audio sample format fourcc type

2024-02-21 Thread Shengjiu Wang 
On Wed, Feb 21, 2024 at 7:10 PM Hans Verkuil  wrote:
>
> On 19/02/2024 13:56, Mauro Carvalho Chehab wrote:
> > Em Mon, 19 Feb 2024 12:05:02 +0800
> > Shengjiu Wang  escreveu:
> >
> >> Hi Mauro
> >>
> >> On Sat, Feb 17, 2024 at 5:19 PM Mauro Carvalho Chehab
> >>  wrote:
> >>>
> >>> Em Thu, 18 Jan 2024 20:32:01 +0800
> >>> Shengjiu Wang  escreveu:
> >>>
>  The audio sample format definition is from alsa,
>  the header file is include/uapi/sound/asound.h, but
>  don't include this header file directly, because in
>  user space, there is another copy in alsa-lib.
>  There will be conflict in userspace for include
>  videodev2.h & asound.h and asoundlib.h
> 
>  Here still use the fourcc format.
> 
>  Signed-off-by: Shengjiu Wang 
>  ---
>   .../userspace-api/media/v4l/pixfmt-audio.rst  | 87 +++
>   .../userspace-api/media/v4l/pixfmt.rst|  1 +
>   drivers/media/v4l2-core/v4l2-ioctl.c  | 13 +++
>   include/uapi/linux/videodev2.h| 23 +
>   4 files changed, 124 insertions(+)
>   create mode 100644 
>  Documentation/userspace-api/media/v4l/pixfmt-audio.rst
> 
>  diff --git a/Documentation/userspace-api/media/v4l/pixfmt-audio.rst 
>  b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
>  new file mode 100644
>  index ..04b4a7fbd8f4
>  --- /dev/null
>  +++ b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
>  @@ -0,0 +1,87 @@
>  +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
>  +
>  +.. _pixfmt-audio:
>  +
>  +*
>  +Audio Formats
>  +*
>  +
>  +These formats are used for :ref:`audiomem2mem` interface only.
>  +
>  +.. tabularcolumns:: |p{5.8cm}|p{1.2cm}|p{10.3cm}|
>  +
>  +.. cssclass:: longtable
>  +
>  +.. flat-table:: Audio Format
>  +:header-rows:  1
>  +:stub-columns: 0
>  +:widths:   3 1 4
>  +
>  +* - Identifier
>  +  - Code
>  +  - Details
>  +* .. _V4L2-AUDIO-FMT-S8:
>  +
>  +  - ``V4L2_AUDIO_FMT_S8``
>  +  - 'S8'
>  +  - Corresponds to SNDRV_PCM_FORMAT_S8 in ALSA
>  +* .. _V4L2-AUDIO-FMT-S16-LE:
> >>>
> >>> Hmm... why can't we just use SNDRV_*_FORMAT_*? Those are already part of
> >>> an uAPI header. No need to add any abstraction here and/or redefine
> >>> what is there already at include/uapi/sound/asound.h.
> >>>
> >> Actually I try to avoid including the include/uapi/sound/asound.h.
> >> Because in user space, there is another copy in alsa-lib (asoundlib.h).
> >> There will be conflict in userspace when including videodev2.h and
> >> asoundlib.h.
> >
> > Well, alsasoundlib.h seems to be using the same definitions:
> >   https://github.com/michaelwu/alsa-lib/blob/master/include/pcm.h
> >
> > So, I can't see what would be the actual issue, as both userspace library
> > and ALSA internal headers use the same magic numbers.
> >
> > You can still do things like:
> >
> >   #ifdef __KERNEL__
> >   #  include 
> >   #else
> >   #  include 
> >   #endif
> >
> > To avoid such kind of conflicts, if you need to have it included on
> > some header file. Yet, I can't see why you would need that.
> >
> > IMO, at uAPI headers, you just need to declare the uAPI audiofmt field
> > to be either __u32 or __u64, pointing it to where this value comes from
> > (on both userspace and Kernelspace. E. g.:
> >
> > /**
> >  * struct v4l2_audio_format - audio data format definition
> >  * @audioformat:
> >  *an integer number matching the fields inside
> >  *enum snd_pcm_format_t (e. g. `SNDRV_PCM_FORMAT_*`), as defined
> >  *in include/uapi/sound/asound.h and
> >  *  
> > https://www.alsa-project.org/alsa-doc/alsa-lib/group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8.
> >  * @channels: channel numbers
> >  * @buffersize:   maximum size in bytes required for data
> >  */
> > struct v4l2_audio_format {
> >   __u32   audioformat;
> >   __u32   channels;
> >   __u32   buffersize;
> > } __attribute__ ((packed));
> >
> > Then, at documentation you just need to point to where the
> > possible values for SNDRV_PCM_FORMAT_ are defined. No need to
> > document them one by one.
> >
> > With such definition, you'll only need to include sound/asound.h
> > within the kAPI scope.
> >
> >>
> >> And in the V4l framework, the fourcc type is commonly used in other
> >> cases (video, radio, touch, meta), to avoid changing common code
> >> a lot, so I think using fourcc definition for audio may be simpler.
> >
> > Those are real video streams (or a video-related streams, in the case
> > of metadata) where fourcc is widely used. There, it makes sense.
> > However, ALSA format definitions are already being used for a long time.
> >

Re: [PATCH v12 08/15] media: uapi: Define audio sample format fourcc type

2024-02-21 Thread Hans Verkuil 
On 19/02/2024 13:56, Mauro Carvalho Chehab wrote:
> Em Mon, 19 Feb 2024 12:05:02 +0800
> Shengjiu Wang  escreveu:
> 
>> Hi Mauro
>>
>> On Sat, Feb 17, 2024 at 5:19 PM Mauro Carvalho Chehab
>>  wrote:
>>>
>>> Em Thu, 18 Jan 2024 20:32:01 +0800
>>> Shengjiu Wang  escreveu:
>>>  
 The audio sample format definition is from alsa,
 the header file is include/uapi/sound/asound.h, but
 don't include this header file directly, because in
 user space, there is another copy in alsa-lib.
 There will be conflict in userspace for include
 videodev2.h & asound.h and asoundlib.h

 Here still use the fourcc format.

 Signed-off-by: Shengjiu Wang 
 ---
  .../userspace-api/media/v4l/pixfmt-audio.rst  | 87 +++
  .../userspace-api/media/v4l/pixfmt.rst|  1 +
  drivers/media/v4l2-core/v4l2-ioctl.c  | 13 +++
  include/uapi/linux/videodev2.h| 23 +
  4 files changed, 124 insertions(+)
  create mode 100644 Documentation/userspace-api/media/v4l/pixfmt-audio.rst

 diff --git a/Documentation/userspace-api/media/v4l/pixfmt-audio.rst 
 b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
 new file mode 100644
 index ..04b4a7fbd8f4
 --- /dev/null
 +++ b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
 @@ -0,0 +1,87 @@
 +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
 +
 +.. _pixfmt-audio:
 +
 +*
 +Audio Formats
 +*
 +
 +These formats are used for :ref:`audiomem2mem` interface only.
 +
 +.. tabularcolumns:: |p{5.8cm}|p{1.2cm}|p{10.3cm}|
 +
 +.. cssclass:: longtable
 +
 +.. flat-table:: Audio Format
 +:header-rows:  1
 +:stub-columns: 0
 +:widths:   3 1 4
 +
 +* - Identifier
 +  - Code
 +  - Details
 +* .. _V4L2-AUDIO-FMT-S8:
 +
 +  - ``V4L2_AUDIO_FMT_S8``
 +  - 'S8'
 +  - Corresponds to SNDRV_PCM_FORMAT_S8 in ALSA
 +* .. _V4L2-AUDIO-FMT-S16-LE:  
>>>
>>> Hmm... why can't we just use SNDRV_*_FORMAT_*? Those are already part of
>>> an uAPI header. No need to add any abstraction here and/or redefine
>>> what is there already at include/uapi/sound/asound.h.
>>>  
>> Actually I try to avoid including the include/uapi/sound/asound.h.
>> Because in user space, there is another copy in alsa-lib (asoundlib.h).
>> There will be conflict in userspace when including videodev2.h and
>> asoundlib.h.
> 
> Well, alsasoundlib.h seems to be using the same definitions:
>   https://github.com/michaelwu/alsa-lib/blob/master/include/pcm.h
> 
> So, I can't see what would be the actual issue, as both userspace library
> and ALSA internal headers use the same magic numbers.
> 
> You can still do things like:
> 
>   #ifdef __KERNEL__
>   #  include 
>   #else
>   #  include 
>   #endif
> 
> To avoid such kind of conflicts, if you need to have it included on
> some header file. Yet, I can't see why you would need that.
> 
> IMO, at uAPI headers, you just need to declare the uAPI audiofmt field
> to be either __u32 or __u64, pointing it to where this value comes from
> (on both userspace and Kernelspace. E. g.:
> 
> /**
>  * struct v4l2_audio_format - audio data format definition
>  * @audioformat:
>  *an integer number matching the fields inside
>  *enum snd_pcm_format_t (e. g. `SNDRV_PCM_FORMAT_*`), as defined
>  *in include/uapi/sound/asound.h and
>  *  
> https://www.alsa-project.org/alsa-doc/alsa-lib/group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8.
>  * @channels: channel numbers
>  * @buffersize:   maximum size in bytes required for data
>  */
> struct v4l2_audio_format {
>   __u32   audioformat;
>   __u32   channels;
>   __u32   buffersize;
> } __attribute__ ((packed));
> 
> Then, at documentation you just need to point to where the
> possible values for SNDRV_PCM_FORMAT_ are defined. No need to
> document them one by one.
> 
> With such definition, you'll only need to include sound/asound.h
> within the kAPI scope.
> 
>>
>> And in the V4l framework, the fourcc type is commonly used in other
>> cases (video, radio, touch, meta), to avoid changing common code
>> a lot, so I think using fourcc definition for audio may be simpler.
> 
> Those are real video streams (or a video-related streams, in the case
> of metadata) where fourcc is widely used. There, it makes sense.
> However, ALSA format definitions are already being used for a long time.
> There's no sense on trying to reinvent it - or having an abstract layer
> to convert from/to fourcc <==> enum snd_pcm_format_t. Just use what is
> there already.

The problem is that within V4L2 we use fourcc consistently to describe a
format, including in VIDIOC_ENUM_FMT. And the expectation is that the

Re: [PATCH v12 08/15] media: uapi: Define audio sample format fourcc type

2024-02-19 Thread Mauro Carvalho Chehab 
Em Mon, 19 Feb 2024 12:05:02 +0800
Shengjiu Wang  escreveu:

> Hi Mauro
> 
> On Sat, Feb 17, 2024 at 5:19 PM Mauro Carvalho Chehab
>  wrote:
> >
> > Em Thu, 18 Jan 2024 20:32:01 +0800
> > Shengjiu Wang  escreveu:
> >  
> > > The audio sample format definition is from alsa,
> > > the header file is include/uapi/sound/asound.h, but
> > > don't include this header file directly, because in
> > > user space, there is another copy in alsa-lib.
> > > There will be conflict in userspace for include
> > > videodev2.h & asound.h and asoundlib.h
> > >
> > > Here still use the fourcc format.
> > >
> > > Signed-off-by: Shengjiu Wang 
> > > ---
> > >  .../userspace-api/media/v4l/pixfmt-audio.rst  | 87 +++
> > >  .../userspace-api/media/v4l/pixfmt.rst|  1 +
> > >  drivers/media/v4l2-core/v4l2-ioctl.c  | 13 +++
> > >  include/uapi/linux/videodev2.h| 23 +
> > >  4 files changed, 124 insertions(+)
> > >  create mode 100644 Documentation/userspace-api/media/v4l/pixfmt-audio.rst
> > >
> > > diff --git a/Documentation/userspace-api/media/v4l/pixfmt-audio.rst 
> > > b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
> > > new file mode 100644
> > > index ..04b4a7fbd8f4
> > > --- /dev/null
> > > +++ b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
> > > @@ -0,0 +1,87 @@
> > > +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
> > > +
> > > +.. _pixfmt-audio:
> > > +
> > > +*
> > > +Audio Formats
> > > +*
> > > +
> > > +These formats are used for :ref:`audiomem2mem` interface only.
> > > +
> > > +.. tabularcolumns:: |p{5.8cm}|p{1.2cm}|p{10.3cm}|
> > > +
> > > +.. cssclass:: longtable
> > > +
> > > +.. flat-table:: Audio Format
> > > +:header-rows:  1
> > > +:stub-columns: 0
> > > +:widths:   3 1 4
> > > +
> > > +* - Identifier
> > > +  - Code
> > > +  - Details
> > > +* .. _V4L2-AUDIO-FMT-S8:
> > > +
> > > +  - ``V4L2_AUDIO_FMT_S8``
> > > +  - 'S8'
> > > +  - Corresponds to SNDRV_PCM_FORMAT_S8 in ALSA
> > > +* .. _V4L2-AUDIO-FMT-S16-LE:  
> >
> > Hmm... why can't we just use SNDRV_*_FORMAT_*? Those are already part of
> > an uAPI header. No need to add any abstraction here and/or redefine
> > what is there already at include/uapi/sound/asound.h.
> >  
> Actually I try to avoid including the include/uapi/sound/asound.h.
> Because in user space, there is another copy in alsa-lib (asoundlib.h).
> There will be conflict in userspace when including videodev2.h and
> asoundlib.h.

Well, alsasoundlib.h seems to be using the same definitions:
https://github.com/michaelwu/alsa-lib/blob/master/include/pcm.h

So, I can't see what would be the actual issue, as both userspace library
and ALSA internal headers use the same magic numbers.

You can still do things like:

#ifdef __KERNEL__
#  include 
#else
#  include 
#endif

To avoid such kind of conflicts, if you need to have it included on
some header file. Yet, I can't see why you would need that.

IMO, at uAPI headers, you just need to declare the uAPI audiofmt field
to be either __u32 or __u64, pointing it to where this value comes from
(on both userspace and Kernelspace. E. g.:

/**
 * struct v4l2_audio_format - audio data format definition
 * @audioformat:
 *  an integer number matching the fields inside
 *  enum snd_pcm_format_t (e. g. `SNDRV_PCM_FORMAT_*`), as defined
 *  in include/uapi/sound/asound.h and
 *  
https://www.alsa-project.org/alsa-doc/alsa-lib/group___p_c_m.html#gaa14b7f26877a812acbb39811364177f8.
 * @channels:   channel numbers
 * @buffersize: maximum size in bytes required for data
 */
struct v4l2_audio_format {
__u32   audioformat;
__u32   channels;
__u32   buffersize;
} __attribute__ ((packed));

Then, at documentation you just need to point to where the
possible values for SNDRV_PCM_FORMAT_ are defined. No need to
document them one by one.

With such definition, you'll only need to include sound/asound.h
within the kAPI scope.

> 
> And in the V4l framework, the fourcc type is commonly used in other
> cases (video, radio, touch, meta), to avoid changing common code
> a lot, so I think using fourcc definition for audio may be simpler.

Those are real video streams (or a video-related streams, in the case
of metadata) where fourcc is widely used. There, it makes sense.
However, ALSA format definitions are already being used for a long time.
There's no sense on trying to reinvent it - or having an abstract layer
to convert from/to fourcc <==> enum snd_pcm_format_t. Just use what is
there already.

Thanks,
Mauro

Re: [PATCH v12 08/15] media: uapi: Define audio sample format fourcc type

2024-02-18 Thread Shengjiu Wang 
Hi Mauro

On Sat, Feb 17, 2024 at 5:19 PM Mauro Carvalho Chehab
 wrote:
>
> Em Thu, 18 Jan 2024 20:32:01 +0800
> Shengjiu Wang  escreveu:
>
> > The audio sample format definition is from alsa,
> > the header file is include/uapi/sound/asound.h, but
> > don't include this header file directly, because in
> > user space, there is another copy in alsa-lib.
> > There will be conflict in userspace for include
> > videodev2.h & asound.h and asoundlib.h
> >
> > Here still use the fourcc format.
> >
> > Signed-off-by: Shengjiu Wang 
> > ---
> >  .../userspace-api/media/v4l/pixfmt-audio.rst  | 87 +++
> >  .../userspace-api/media/v4l/pixfmt.rst|  1 +
> >  drivers/media/v4l2-core/v4l2-ioctl.c  | 13 +++
> >  include/uapi/linux/videodev2.h| 23 +
> >  4 files changed, 124 insertions(+)
> >  create mode 100644 Documentation/userspace-api/media/v4l/pixfmt-audio.rst
> >
> > diff --git a/Documentation/userspace-api/media/v4l/pixfmt-audio.rst 
> > b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
> > new file mode 100644
> > index ..04b4a7fbd8f4
> > --- /dev/null
> > +++ b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
> > @@ -0,0 +1,87 @@
> > +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
> > +
> > +.. _pixfmt-audio:
> > +
> > +*
> > +Audio Formats
> > +*
> > +
> > +These formats are used for :ref:`audiomem2mem` interface only.
> > +
> > +.. tabularcolumns:: |p{5.8cm}|p{1.2cm}|p{10.3cm}|
> > +
> > +.. cssclass:: longtable
> > +
> > +.. flat-table:: Audio Format
> > +:header-rows:  1
> > +:stub-columns: 0
> > +:widths:   3 1 4
> > +
> > +* - Identifier
> > +  - Code
> > +  - Details
> > +* .. _V4L2-AUDIO-FMT-S8:
> > +
> > +  - ``V4L2_AUDIO_FMT_S8``
> > +  - 'S8'
> > +  - Corresponds to SNDRV_PCM_FORMAT_S8 in ALSA
> > +* .. _V4L2-AUDIO-FMT-S16-LE:
>
> Hmm... why can't we just use SNDRV_*_FORMAT_*? Those are already part of
> an uAPI header. No need to add any abstraction here and/or redefine
> what is there already at include/uapi/sound/asound.h.
>
Actually I try to avoid including the include/uapi/sound/asound.h.
Because in user space, there is another copy in alsa-lib (asoundlib.h).
There will be conflict in userspace when including videodev2.h and
asoundlib.h.

And in the V4l framework, the fourcc type is commonly used in other
cases (video, radio, touch, meta), to avoid changing common code
a lot, so I think using fourcc definition for audio may be simpler.

Best regards
Shengjiu Wang

Re: [PATCH v12 08/15] media: uapi: Define audio sample format fourcc type

2024-02-17 Thread Mauro Carvalho Chehab 
Em Thu, 18 Jan 2024 20:32:01 +0800
Shengjiu Wang  escreveu:

> The audio sample format definition is from alsa,
> the header file is include/uapi/sound/asound.h, but
> don't include this header file directly, because in
> user space, there is another copy in alsa-lib.
> There will be conflict in userspace for include
> videodev2.h & asound.h and asoundlib.h
> 
> Here still use the fourcc format.
> 
> Signed-off-by: Shengjiu Wang 
> ---
>  .../userspace-api/media/v4l/pixfmt-audio.rst  | 87 +++
>  .../userspace-api/media/v4l/pixfmt.rst|  1 +
>  drivers/media/v4l2-core/v4l2-ioctl.c  | 13 +++
>  include/uapi/linux/videodev2.h| 23 +
>  4 files changed, 124 insertions(+)
>  create mode 100644 Documentation/userspace-api/media/v4l/pixfmt-audio.rst
> 
> diff --git a/Documentation/userspace-api/media/v4l/pixfmt-audio.rst 
> b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
> new file mode 100644
> index ..04b4a7fbd8f4
> --- /dev/null
> +++ b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
> @@ -0,0 +1,87 @@
> +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
> +
> +.. _pixfmt-audio:
> +
> +*
> +Audio Formats
> +*
> +
> +These formats are used for :ref:`audiomem2mem` interface only.
> +
> +.. tabularcolumns:: |p{5.8cm}|p{1.2cm}|p{10.3cm}|
> +
> +.. cssclass:: longtable
> +
> +.. flat-table:: Audio Format
> +:header-rows:  1
> +:stub-columns: 0
> +:widths:   3 1 4
> +
> +* - Identifier
> +  - Code
> +  - Details
> +* .. _V4L2-AUDIO-FMT-S8:
> +
> +  - ``V4L2_AUDIO_FMT_S8``
> +  - 'S8'
> +  - Corresponds to SNDRV_PCM_FORMAT_S8 in ALSA
> +* .. _V4L2-AUDIO-FMT-S16-LE:

Hmm... why can't we just use SNDRV_*_FORMAT_*? Those are already part of
an uAPI header. No need to add any abstraction here and/or redefine
what is there already at include/uapi/sound/asound.h.

Thanks,
Mauro

[PATCH v12 08/15] media: uapi: Define audio sample format fourcc type

2024-01-18 Thread Shengjiu Wang 
The audio sample format definition is from alsa,
the header file is include/uapi/sound/asound.h, but
don't include this header file directly, because in
user space, there is another copy in alsa-lib.
There will be conflict in userspace for include
videodev2.h & asound.h and asoundlib.h

Here still use the fourcc format.

Signed-off-by: Shengjiu Wang 
---
 .../userspace-api/media/v4l/pixfmt-audio.rst  | 87 +++
 .../userspace-api/media/v4l/pixfmt.rst|  1 +
 drivers/media/v4l2-core/v4l2-ioctl.c  | 13 +++
 include/uapi/linux/videodev2.h| 23 +
 4 files changed, 124 insertions(+)
 create mode 100644 Documentation/userspace-api/media/v4l/pixfmt-audio.rst

diff --git a/Documentation/userspace-api/media/v4l/pixfmt-audio.rst 
b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
new file mode 100644
index ..04b4a7fbd8f4
--- /dev/null
+++ b/Documentation/userspace-api/media/v4l/pixfmt-audio.rst
@@ -0,0 +1,87 @@
+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+
+.. _pixfmt-audio:
+
+*
+Audio Formats
+*
+
+These formats are used for :ref:`audiomem2mem` interface only.
+
+.. tabularcolumns:: |p{5.8cm}|p{1.2cm}|p{10.3cm}|
+
+.. cssclass:: longtable
+
+.. flat-table:: Audio Format
+:header-rows:  1
+:stub-columns: 0
+:widths:   3 1 4
+
+* - Identifier
+  - Code
+  - Details
+* .. _V4L2-AUDIO-FMT-S8:
+
+  - ``V4L2_AUDIO_FMT_S8``
+  - 'S8'
+  - Corresponds to SNDRV_PCM_FORMAT_S8 in ALSA
+* .. _V4L2-AUDIO-FMT-S16-LE:
+
+  - ``V4L2_AUDIO_FMT_S16_LE``
+  - 'S16_LE'
+  - Corresponds to SNDRV_PCM_FORMAT_S16_LE in ALSA
+* .. _V4L2-AUDIO-FMT-U16-LE:
+
+  - ``V4L2_AUDIO_FMT_U16_LE``
+  - 'U16_LE'
+  - Corresponds to SNDRV_PCM_FORMAT_U16_LE in ALSA
+* .. _V4L2-AUDIO-FMT-S24-LE:
+
+  - ``V4L2_AUDIO_FMT_S24_LE``
+  - 'S24_LE'
+  - Corresponds to SNDRV_PCM_FORMAT_S24_LE in ALSA
+* .. _V4L2-AUDIO-FMT-U24-LE:
+
+  - ``V4L2_AUDIO_FMT_U24_LE``
+  - 'U24_LE'
+  - Corresponds to SNDRV_PCM_FORMAT_U24_LE in ALSA
+* .. _V4L2-AUDIO-FMT-S32-LE:
+
+  - ``V4L2_AUDIO_FMT_S32_LE``
+  - 'S32_LE'
+  - Corresponds to SNDRV_PCM_FORMAT_S32_LE in ALSA
+* .. _V4L2-AUDIO-FMT-U32-LE:
+
+  - ``V4L2_AUDIO_FMT_U32_LE``
+  - 'U32_LE'
+  - Corresponds to SNDRV_PCM_FORMAT_U32_LE in ALSA
+* .. _V4L2-AUDIO-FMT-FLOAT-LE:
+
+  - ``V4L2_AUDIO_FMT_FLOAT_LE``
+  - 'FLOAT_LE'
+  - Corresponds to SNDRV_PCM_FORMAT_FLOAT_LE in ALSA
+* .. _V4L2-AUDIO-FMT-IEC958-SUBFRAME-LE:
+
+  - ``V4L2_AUDIO_FMT_IEC958_SUBFRAME_LE``
+  - 'IEC958_SUBFRAME_LE'
+  - Corresponds to SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE in ALSA
+* .. _V4L2-AUDIO-FMT-S24-3LE:
+
+  - ``V4L2_AUDIO_FMT_S24_3LE``
+  - 'S24_3LE'
+  - Corresponds to SNDRV_PCM_FORMAT_S24_3LE in ALSA
+* .. _V4L2-AUDIO-FMT-U24-3LE:
+
+  - ``V4L2_AUDIO_FMT_U24_3LE``
+  - 'U24_3LE'
+  - Corresponds to SNDRV_PCM_FORMAT_U24_3LE in ALSA
+* .. _V4L2-AUDIO-FMT-S20-3LE:
+
+  - ``V4L2_AUDIO_FMT_S20_3LE``
+  - 'S20_3LE'
+  - Corresponds to SNDRV_PCM_FORMAT_S24_3LE in ALSA
+* .. _V4L2-AUDIO-FMT-U20-3LE:
+
+  - ``V4L2_AUDIO_FMT_U20_3LE``
+  - 'U20_3LE'
+  - Corresponds to SNDRV_PCM_FORMAT_U20_3LE in ALSA
diff --git a/Documentation/userspace-api/media/v4l/pixfmt.rst 
b/Documentation/userspace-api/media/v4l/pixfmt.rst
index 11dab4a90630..2eb6fdd3b43d 100644
--- a/Documentation/userspace-api/media/v4l/pixfmt.rst
+++ b/Documentation/userspace-api/media/v4l/pixfmt.rst
@@ -36,3 +36,4 @@ see also :ref:`VIDIOC_G_FBUF `.)
 colorspaces
 colorspaces-defs
 colorspaces-details
+pixfmt-audio
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c 
b/drivers/media/v4l2-core/v4l2-ioctl.c
index e7be7c2f302d..e5094f0e75c1 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -1471,6 +1471,19 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
case V4L2_PIX_FMT_Y210: descr = "10-bit YUYV Packed"; break;
case V4L2_PIX_FMT_Y212: descr = "12-bit YUYV Packed"; break;
case V4L2_PIX_FMT_Y216: descr = "16-bit YUYV Packed"; break;
+   case V4L2_AUDIO_FMT_S8: descr = "8-bit Signed"; break;
+   case V4L2_AUDIO_FMT_S16_LE: descr = "16-bit Signed LE"; break;
+   case V4L2_AUDIO_FMT_U16_LE: descr = "16-bit Unsigned LE"; 
break;
+   case V4L2_AUDIO_FMT_S24_LE: descr = "24(32)-bit Signed LE"; 
break;
+   case V4L2_AUDIO_FMT_U24_LE: descr = "24(32)-bit Unsigned 
LE"; break;
+   case V4L2_AUDIO_FMT_S32_LE: descr = "32-bit Signed LE"; 
break;
+   case V4L2_AUDIO_FMT_U32_LE: descr = "32-bit Unsigned LE"; 
break;
+   case V4L2_AUDIO_FMT_FLOAT_LE:   descr = "32-bit Float LE"; 
break;
+   case V4L2_AUDIO_FMT_IEC958_SUBFRAME_LE: descr =