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[PATCH v5 1/3] media: videodev2: Add flag to unconditionnaly enumerate pixels formats

Benjamin Gaignard posted 3 patches 1 year, 6 months ago
There is a newer version of this series
[PATCH v5 1/3] media: videodev2: Add flag to unconditionnaly enumerate pixels formats
Posted by Benjamin Gaignard 1 year, 6 months ago 
When the index field is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver
will ignore any configuration and enumerate all the possible formats.
Drivers which do not support this flag yet always return an EINVAL
error code.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
---
changes in version 5:
- Reset the proposal to follow Hans's advices
- Add new flag to be used with index field.

 .../userspace-api/media/v4l/vidioc-enum-fmt.rst      | 12 +++++++++++-
 .../userspace-api/media/videodev2.h.rst.exceptions   |  1 +
 include/uapi/linux/videodev2.h                       |  3 +++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
index 3adb3d205531..12e1e65e6a71 100644
--- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
+++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
@@ -85,7 +85,11 @@ the ``mbus_code`` field is handled differently:
     * - __u32
       - ``index``
       - Number of the format in the enumeration, set by the application.
-	This is in no way related to the ``pixelformat`` field.
+        This is in no way related to the ``pixelformat`` field. When the
+        index is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver will ignore
+        any configuration and enumerate all the possible formats. Drivers
+        which do not support this flag yet always return an ``EINVAL``
+        error code.
     * - __u32
       - ``type``
       - Type of the data stream, set by the application. Only these types
@@ -234,6 +238,12 @@ the ``mbus_code`` field is handled differently:
 	valid. The buffer consists of ``height`` lines, each having ``width``
 	Data Units of data and the offset (in bytes) between the beginning of
 	each two consecutive lines is ``bytesperline``.
+    * - ``V4L2_FMT_FLAG_ENUM_ALL``
+      - 0x80000000
+      - When the applications ORs ``index`` with ``V4L2_FMT_FLAG_ENUM_ALL`` flag
+        the driver enumerates all the possible pixel formats without taking care
+        of any already set configuration. Drivers which do not support this flag
+        yet always return ``EINVAL``.
 
 Return Value
 ============
diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
index bdc628e8c1d6..8dc10a500fc6 100644
--- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions
+++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
@@ -216,6 +216,7 @@ replace define V4L2_FMT_FLAG_CSC_YCBCR_ENC fmtdesc-flags
 replace define V4L2_FMT_FLAG_CSC_HSV_ENC fmtdesc-flags
 replace define V4L2_FMT_FLAG_CSC_QUANTIZATION fmtdesc-flags
 replace define V4L2_FMT_FLAG_META_LINE_BASED fmtdesc-flags
+replace define V4L2_FMT_FLAG_ENUM_ALL fmtdesc-flags
 
 # V4L2 timecode types
 replace define V4L2_TC_TYPE_24FPS timecode-type
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 4e91362da6da..3d11f91273a1 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -904,6 +904,9 @@ struct v4l2_fmtdesc {
 #define V4L2_FMT_FLAG_CSC_QUANTIZATION		0x0100
 #define V4L2_FMT_FLAG_META_LINE_BASED		0x0200
 
+/*  Format description flag, to be ORed with the index */
+#define V4L2_FMT_FLAG_ENUM_ALL			0x80000000
+
 	/* Frame Size and frame rate enumeration */
 /*
  *	F R A M E   S I Z E   E N U M E R A T I O N
-- 
2.43.0
Re: [PATCH v5 1/3] media: videodev2: Add flag to unconditionnaly enumerate pixels formats
Posted by Hans Verkuil 1 year, 6 months ago 
On 22/07/2024 17:05, Benjamin Gaignard wrote:
> When the index field is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver
> will ignore any configuration and enumerate all the possible formats.
> Drivers which do not support this flag yet always return an EINVAL
> error code.
> 
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
> ---
> changes in version 5:
> - Reset the proposal to follow Hans's advices
> - Add new flag to be used with index field.
> 
>  .../userspace-api/media/v4l/vidioc-enum-fmt.rst      | 12 +++++++++++-
>  .../userspace-api/media/videodev2.h.rst.exceptions   |  1 +
>  include/uapi/linux/videodev2.h                       |  3 +++
>  3 files changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
> index 3adb3d205531..12e1e65e6a71 100644
> --- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
> +++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
> @@ -85,7 +85,11 @@ the ``mbus_code`` field is handled differently:
>      * - __u32
>        - ``index``
>        - Number of the format in the enumeration, set by the application.
> -	This is in no way related to the ``pixelformat`` field.
> +        This is in no way related to the ``pixelformat`` field. When the

You need to start a new paragraph before 'When'. Otherwise you might read
that the 'When' sentence is somehow related to the previous sentence.

> +        index is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver will ignore
> +        any configuration and enumerate all the possible formats. Drivers

I'd rephrase this a little bit:

the driver will enumerate all the possible formats, ignoring any limitations
from the current configuration.

And after that I would like to see an example of a use-case.

> +        which do not support this flag yet always return an ``EINVAL``
> +        error code.
>      * - __u32
>        - ``type``
>        - Type of the data stream, set by the application. Only these types
> @@ -234,6 +238,12 @@ the ``mbus_code`` field is handled differently:
>  	valid. The buffer consists of ``height`` lines, each having ``width``
>  	Data Units of data and the offset (in bytes) between the beginning of
>  	each two consecutive lines is ``bytesperline``.
> +    * - ``V4L2_FMT_FLAG_ENUM_ALL``

I am not really happy with this name since the prefix is identical to that
of other V4L2_FMT_FLAG_ defines. How about: V4L2_FMTDESC_FLAG_ENUM_ALL?
Or V4L2_FMT_IDX_ENUM_ALL?

> +      - 0x80000000
> +      - When the applications ORs ``index`` with ``V4L2_FMT_FLAG_ENUM_ALL`` flag
> +        the driver enumerates all the possible pixel formats without taking care
> +        of any already set configuration. Drivers which do not support this flag
> +        yet always return ``EINVAL``.
>  
>  Return Value
>  ============
> diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> index bdc628e8c1d6..8dc10a500fc6 100644
> --- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> +++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
> @@ -216,6 +216,7 @@ replace define V4L2_FMT_FLAG_CSC_YCBCR_ENC fmtdesc-flags
>  replace define V4L2_FMT_FLAG_CSC_HSV_ENC fmtdesc-flags
>  replace define V4L2_FMT_FLAG_CSC_QUANTIZATION fmtdesc-flags
>  replace define V4L2_FMT_FLAG_META_LINE_BASED fmtdesc-flags
> +replace define V4L2_FMT_FLAG_ENUM_ALL fmtdesc-flags
>  
>  # V4L2 timecode types
>  replace define V4L2_TC_TYPE_24FPS timecode-type
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 4e91362da6da..3d11f91273a1 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -904,6 +904,9 @@ struct v4l2_fmtdesc {
>  #define V4L2_FMT_FLAG_CSC_QUANTIZATION		0x0100
>  #define V4L2_FMT_FLAG_META_LINE_BASED		0x0200
>  
> +/*  Format description flag, to be ORed with the index */
> +#define V4L2_FMT_FLAG_ENUM_ALL			0x80000000
> +
>  	/* Frame Size and frame rate enumeration */
>  /*
>   *	F R A M E   S I Z E   E N U M E R A T I O N

Regards,

	Hans
Re: [PATCH v5 1/3] media: videodev2: Add flag to unconditionnaly enumerate pixels formats
Posted by Benjamin Gaignard 1 year, 6 months ago 
Le 30/07/2024 à 09:08, Hans Verkuil a écrit :
> On 22/07/2024 17:05, Benjamin Gaignard wrote:
>> When the index field is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver
>> will ignore any configuration and enumerate all the possible formats.
>> Drivers which do not support this flag yet always return an EINVAL
>> error code.
>>
>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
>> ---
>> changes in version 5:
>> - Reset the proposal to follow Hans's advices
>> - Add new flag to be used with index field.
>>
>>   .../userspace-api/media/v4l/vidioc-enum-fmt.rst      | 12 +++++++++++-
>>   .../userspace-api/media/videodev2.h.rst.exceptions   |  1 +
>>   include/uapi/linux/videodev2.h                       |  3 +++
>>   3 files changed, 15 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>> index 3adb3d205531..12e1e65e6a71 100644
>> --- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>> +++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>> @@ -85,7 +85,11 @@ the ``mbus_code`` field is handled differently:
>>       * - __u32
>>         - ``index``
>>         - Number of the format in the enumeration, set by the application.
>> -	This is in no way related to the ``pixelformat`` field.
>> +        This is in no way related to the ``pixelformat`` field. When the
> You need to start a new paragraph before 'When'. Otherwise you might read
> that the 'When' sentence is somehow related to the previous sentence.
>
>> +        index is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver will ignore
>> +        any configuration and enumerate all the possible formats. Drivers
> I'd rephrase this a little bit:
>
> the driver will enumerate all the possible formats, ignoring any limitations
> from the current configuration.
>
> And after that I would like to see an example of a use-case.
>
>> +        which do not support this flag yet always return an ``EINVAL``
>> +        error code.
>>       * - __u32
>>         - ``type``
>>         - Type of the data stream, set by the application. Only these types
>> @@ -234,6 +238,12 @@ the ``mbus_code`` field is handled differently:
>>   	valid. The buffer consists of ``height`` lines, each having ``width``
>>   	Data Units of data and the offset (in bytes) between the beginning of
>>   	each two consecutive lines is ``bytesperline``.
>> +    * - ``V4L2_FMT_FLAG_ENUM_ALL``
> I am not really happy with this name since the prefix is identical to that
> of other V4L2_FMT_FLAG_ defines. How about: V4L2_FMTDESC_FLAG_ENUM_ALL?
> Or V4L2_FMT_IDX_ENUM_ALL?

I will use V4L2_FMTDESC_FLAG_ENUM_ALL in the next version.

Regards,
Benjamin

>
>> +      - 0x80000000
>> +      - When the applications ORs ``index`` with ``V4L2_FMT_FLAG_ENUM_ALL`` flag
>> +        the driver enumerates all the possible pixel formats without taking care
>> +        of any already set configuration. Drivers which do not support this flag
>> +        yet always return ``EINVAL``.
>>   
>>   Return Value
>>   ============
>> diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>> index bdc628e8c1d6..8dc10a500fc6 100644
>> --- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>> +++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>> @@ -216,6 +216,7 @@ replace define V4L2_FMT_FLAG_CSC_YCBCR_ENC fmtdesc-flags
>>   replace define V4L2_FMT_FLAG_CSC_HSV_ENC fmtdesc-flags
>>   replace define V4L2_FMT_FLAG_CSC_QUANTIZATION fmtdesc-flags
>>   replace define V4L2_FMT_FLAG_META_LINE_BASED fmtdesc-flags
>> +replace define V4L2_FMT_FLAG_ENUM_ALL fmtdesc-flags
>>   
>>   # V4L2 timecode types
>>   replace define V4L2_TC_TYPE_24FPS timecode-type
>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
>> index 4e91362da6da..3d11f91273a1 100644
>> --- a/include/uapi/linux/videodev2.h
>> +++ b/include/uapi/linux/videodev2.h
>> @@ -904,6 +904,9 @@ struct v4l2_fmtdesc {
>>   #define V4L2_FMT_FLAG_CSC_QUANTIZATION		0x0100
>>   #define V4L2_FMT_FLAG_META_LINE_BASED		0x0200
>>   
>> +/*  Format description flag, to be ORed with the index */
>> +#define V4L2_FMT_FLAG_ENUM_ALL			0x80000000
>> +
>>   	/* Frame Size and frame rate enumeration */
>>   /*
>>    *	F R A M E   S I Z E   E N U M E R A T I O N
> Regards,
>
> 	Hans
>
Re: [PATCH v5 1/3] media: videodev2: Add flag to unconditionnaly enumerate pixels formats
Posted by Hans Verkuil 1 year, 6 months ago 
On 30/07/2024 09:08, Hans Verkuil wrote:
> On 22/07/2024 17:05, Benjamin Gaignard wrote:
>> When the index field is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver
>> will ignore any configuration and enumerate all the possible formats.
>> Drivers which do not support this flag yet always return an EINVAL
>> error code.
>>
>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
>> ---
>> changes in version 5:
>> - Reset the proposal to follow Hans's advices
>> - Add new flag to be used with index field.
>>
>>  .../userspace-api/media/v4l/vidioc-enum-fmt.rst      | 12 +++++++++++-
>>  .../userspace-api/media/videodev2.h.rst.exceptions   |  1 +
>>  include/uapi/linux/videodev2.h                       |  3 +++
>>  3 files changed, 15 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>> index 3adb3d205531..12e1e65e6a71 100644
>> --- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>> +++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>> @@ -85,7 +85,11 @@ the ``mbus_code`` field is handled differently:
>>      * - __u32
>>        - ``index``
>>        - Number of the format in the enumeration, set by the application.
>> -	This is in no way related to the ``pixelformat`` field.
>> +        This is in no way related to the ``pixelformat`` field. When the
> 
> You need to start a new paragraph before 'When'. Otherwise you might read
> that the 'When' sentence is somehow related to the previous sentence.
> 
>> +        index is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver will ignore
>> +        any configuration and enumerate all the possible formats. Drivers
> 
> I'd rephrase this a little bit:
> 
> the driver will enumerate all the possible formats, ignoring any limitations
> from the current configuration.
> 
> And after that I would like to see an example of a use-case.

Should the flag be kept on return of VIDIOC_ENUM_FMT or should it be cleared?
For reference: VIDIOC_QUERYCTRL will clear the V4L2_CTRL_FLAG_NEXT_CTRL flag.

Regardless of what we pick, it should be documented.

Regards,

	Hans

> 
>> +        which do not support this flag yet always return an ``EINVAL``
>> +        error code.
>>      * - __u32
>>        - ``type``
>>        - Type of the data stream, set by the application. Only these types
>> @@ -234,6 +238,12 @@ the ``mbus_code`` field is handled differently:
>>  	valid. The buffer consists of ``height`` lines, each having ``width``
>>  	Data Units of data and the offset (in bytes) between the beginning of
>>  	each two consecutive lines is ``bytesperline``.
>> +    * - ``V4L2_FMT_FLAG_ENUM_ALL``
> 
> I am not really happy with this name since the prefix is identical to that
> of other V4L2_FMT_FLAG_ defines. How about: V4L2_FMTDESC_FLAG_ENUM_ALL?
> Or V4L2_FMT_IDX_ENUM_ALL?
> 
>> +      - 0x80000000
>> +      - When the applications ORs ``index`` with ``V4L2_FMT_FLAG_ENUM_ALL`` flag
>> +        the driver enumerates all the possible pixel formats without taking care
>> +        of any already set configuration. Drivers which do not support this flag
>> +        yet always return ``EINVAL``.
>>  
>>  Return Value
>>  ============
>> diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>> index bdc628e8c1d6..8dc10a500fc6 100644
>> --- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>> +++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>> @@ -216,6 +216,7 @@ replace define V4L2_FMT_FLAG_CSC_YCBCR_ENC fmtdesc-flags
>>  replace define V4L2_FMT_FLAG_CSC_HSV_ENC fmtdesc-flags
>>  replace define V4L2_FMT_FLAG_CSC_QUANTIZATION fmtdesc-flags
>>  replace define V4L2_FMT_FLAG_META_LINE_BASED fmtdesc-flags
>> +replace define V4L2_FMT_FLAG_ENUM_ALL fmtdesc-flags
>>  
>>  # V4L2 timecode types
>>  replace define V4L2_TC_TYPE_24FPS timecode-type
>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
>> index 4e91362da6da..3d11f91273a1 100644
>> --- a/include/uapi/linux/videodev2.h
>> +++ b/include/uapi/linux/videodev2.h
>> @@ -904,6 +904,9 @@ struct v4l2_fmtdesc {
>>  #define V4L2_FMT_FLAG_CSC_QUANTIZATION		0x0100
>>  #define V4L2_FMT_FLAG_META_LINE_BASED		0x0200
>>  
>> +/*  Format description flag, to be ORed with the index */
>> +#define V4L2_FMT_FLAG_ENUM_ALL			0x80000000
>> +
>>  	/* Frame Size and frame rate enumeration */
>>  /*
>>   *	F R A M E   S I Z E   E N U M E R A T I O N
> 
> Regards,
> 
> 	Hans
>
Re: [PATCH v5 1/3] media: videodev2: Add flag to unconditionnaly enumerate pixels formats
Posted by Benjamin Gaignard 1 year, 6 months ago 
Le 30/07/2024 à 09:19, Hans Verkuil a écrit :
> On 30/07/2024 09:08, Hans Verkuil wrote:
>> On 22/07/2024 17:05, Benjamin Gaignard wrote:
>>> When the index field is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver
>>> will ignore any configuration and enumerate all the possible formats.
>>> Drivers which do not support this flag yet always return an EINVAL
>>> error code.
>>>
>>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
>>> ---
>>> changes in version 5:
>>> - Reset the proposal to follow Hans's advices
>>> - Add new flag to be used with index field.
>>>
>>>   .../userspace-api/media/v4l/vidioc-enum-fmt.rst      | 12 +++++++++++-
>>>   .../userspace-api/media/videodev2.h.rst.exceptions   |  1 +
>>>   include/uapi/linux/videodev2.h                       |  3 +++
>>>   3 files changed, 15 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>>> index 3adb3d205531..12e1e65e6a71 100644
>>> --- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>>> +++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>>> @@ -85,7 +85,11 @@ the ``mbus_code`` field is handled differently:
>>>       * - __u32
>>>         - ``index``
>>>         - Number of the format in the enumeration, set by the application.
>>> -	This is in no way related to the ``pixelformat`` field.
>>> +        This is in no way related to the ``pixelformat`` field. When the
>> You need to start a new paragraph before 'When'. Otherwise you might read
>> that the 'When' sentence is somehow related to the previous sentence.
>>
>>> +        index is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver will ignore
>>> +        any configuration and enumerate all the possible formats. Drivers
>> I'd rephrase this a little bit:
>>
>> the driver will enumerate all the possible formats, ignoring any limitations
>> from the current configuration.
>>
>> And after that I would like to see an example of a use-case.
> Should the flag be kept on return of VIDIOC_ENUM_FMT or should it be cleared?
> For reference: VIDIOC_QUERYCTRL will clear the V4L2_CTRL_FLAG_NEXT_CTRL flag.
>
> Regardless of what we pick, it should be documented.

I believe most of the flags are cleared in v4l2 so I will to do the same and
document it.

>
> Regards,
>
> 	Hans
>
>>> +        which do not support this flag yet always return an ``EINVAL``
>>> +        error code.
>>>       * - __u32
>>>         - ``type``
>>>         - Type of the data stream, set by the application. Only these types
>>> @@ -234,6 +238,12 @@ the ``mbus_code`` field is handled differently:
>>>   	valid. The buffer consists of ``height`` lines, each having ``width``
>>>   	Data Units of data and the offset (in bytes) between the beginning of
>>>   	each two consecutive lines is ``bytesperline``.
>>> +    * - ``V4L2_FMT_FLAG_ENUM_ALL``
>> I am not really happy with this name since the prefix is identical to that
>> of other V4L2_FMT_FLAG_ defines. How about: V4L2_FMTDESC_FLAG_ENUM_ALL?
>> Or V4L2_FMT_IDX_ENUM_ALL?
>>
>>> +      - 0x80000000
>>> +      - When the applications ORs ``index`` with ``V4L2_FMT_FLAG_ENUM_ALL`` flag
>>> +        the driver enumerates all the possible pixel formats without taking care
>>> +        of any already set configuration. Drivers which do not support this flag
>>> +        yet always return ``EINVAL``.
>>>   
>>>   Return Value
>>>   ============
>>> diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>>> index bdc628e8c1d6..8dc10a500fc6 100644
>>> --- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>>> +++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>>> @@ -216,6 +216,7 @@ replace define V4L2_FMT_FLAG_CSC_YCBCR_ENC fmtdesc-flags
>>>   replace define V4L2_FMT_FLAG_CSC_HSV_ENC fmtdesc-flags
>>>   replace define V4L2_FMT_FLAG_CSC_QUANTIZATION fmtdesc-flags
>>>   replace define V4L2_FMT_FLAG_META_LINE_BASED fmtdesc-flags
>>> +replace define V4L2_FMT_FLAG_ENUM_ALL fmtdesc-flags
>>>   
>>>   # V4L2 timecode types
>>>   replace define V4L2_TC_TYPE_24FPS timecode-type
>>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
>>> index 4e91362da6da..3d11f91273a1 100644
>>> --- a/include/uapi/linux/videodev2.h
>>> +++ b/include/uapi/linux/videodev2.h
>>> @@ -904,6 +904,9 @@ struct v4l2_fmtdesc {
>>>   #define V4L2_FMT_FLAG_CSC_QUANTIZATION		0x0100
>>>   #define V4L2_FMT_FLAG_META_LINE_BASED		0x0200
>>>   
>>> +/*  Format description flag, to be ORed with the index */
>>> +#define V4L2_FMT_FLAG_ENUM_ALL			0x80000000
>>> +
>>>   	/* Frame Size and frame rate enumeration */
>>>   /*
>>>    *	F R A M E   S I Z E   E N U M E R A T I O N
>> Regards,
>>
>> 	Hans
>>
>
Re: [PATCH v5 1/3] media: videodev2: Add flag to unconditionnaly enumerate pixels formats
Posted by Sebastian Fricke 1 year, 6 months ago 
Hey Benjamin,

in the subject line:

s/unconditionnaly enumerate pixels/unconditionally enumerate pixel/

On 22.07.2024 17:05, Benjamin Gaignard wrote:
>When the index field is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver

s/is ORed with/is set with/ (same meaning but a lot less confusing)

>will ignore any configuration and enumerate all the possible formats.
>Drivers which do not support this flag yet always return an EINVAL

s/yet always/yet, always/

>error code.
>
>Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
>---
>changes in version 5:
>- Reset the proposal to follow Hans's advices
>- Add new flag to be used with index field.
>
> .../userspace-api/media/v4l/vidioc-enum-fmt.rst      | 12 +++++++++++-
> .../userspace-api/media/videodev2.h.rst.exceptions   |  1 +
> include/uapi/linux/videodev2.h                       |  3 +++
> 3 files changed, 15 insertions(+), 1 deletion(-)
>
>diff --git a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>index 3adb3d205531..12e1e65e6a71 100644
>--- a/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>+++ b/Documentation/userspace-api/media/v4l/vidioc-enum-fmt.rst
>@@ -85,7 +85,11 @@ the ``mbus_code`` field is handled differently:
>     * - __u32
>       - ``index``
>       - Number of the format in the enumeration, set by the application.
>-	This is in no way related to the ``pixelformat`` field.
>+        This is in no way related to the ``pixelformat`` field. When the
>+        index is ORed with V4L2_FMT_FLAG_ENUM_ALL the driver will ignore

s/ORed/set/ (same as above)

>+        any configuration and enumerate all the possible formats. Drivers
>+        which do not support this flag yet always return an ``EINVAL``

s/yet always/yet, always/

>+        error code.
>     * - __u32
>       - ``type``
>       - Type of the data stream, set by the application. Only these types
>@@ -234,6 +238,12 @@ the ``mbus_code`` field is handled differently:
> 	valid. The buffer consists of ``height`` lines, each having ``width``
> 	Data Units of data and the offset (in bytes) between the beginning of
> 	each two consecutive lines is ``bytesperline``.
>+    * - ``V4L2_FMT_FLAG_ENUM_ALL``
>+      - 0x80000000
>+      - When the applications ORs ``index`` with ``V4L2_FMT_FLAG_ENUM_ALL`` flag

s/applications/application/
s/ORs/sets/

>+        the driver enumerates all the possible pixel formats without taking care
>+        of any already set configuration. Drivers which do not support this flag
>+        yet always return ``EINVAL``.

s/yet always/yet, always/

>
> Return Value
> ============
>diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>index bdc628e8c1d6..8dc10a500fc6 100644
>--- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>+++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
>@@ -216,6 +216,7 @@ replace define V4L2_FMT_FLAG_CSC_YCBCR_ENC fmtdesc-flags
> replace define V4L2_FMT_FLAG_CSC_HSV_ENC fmtdesc-flags
> replace define V4L2_FMT_FLAG_CSC_QUANTIZATION fmtdesc-flags
> replace define V4L2_FMT_FLAG_META_LINE_BASED fmtdesc-flags
>+replace define V4L2_FMT_FLAG_ENUM_ALL fmtdesc-flags
>
> # V4L2 timecode types
> replace define V4L2_TC_TYPE_24FPS timecode-type
>diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
>index 4e91362da6da..3d11f91273a1 100644
>--- a/include/uapi/linux/videodev2.h
>+++ b/include/uapi/linux/videodev2.h
>@@ -904,6 +904,9 @@ struct v4l2_fmtdesc {
> #define V4L2_FMT_FLAG_CSC_QUANTIZATION		0x0100
> #define V4L2_FMT_FLAG_META_LINE_BASED		0x0200
>
>+/*  Format description flag, to be ORed with the index */

s/ORed/set/

Regards,
Sebastian

>+#define V4L2_FMT_FLAG_ENUM_ALL			0x80000000
>+
> 	/* Frame Size and frame rate enumeration */
> /*
>  *	F R A M E   S I Z E   E N U M E R A T I O N
>-- 
>2.43.0
>
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