Re: [PATCH RFC 1/5] V4L: Add V4L2_MBUS_FMT_S5C_UYVY_JPEG_1X8 media bus format

[Sylwester Nawrocki <s.nawrocki@samsung.com>]

Hi Laurent,

Thanks for your review.

On 09/25/2012 01:42 PM, Laurent Pinchart wrote:
> On Monday 24 September 2012 16:55:42 Sylwester Nawrocki wrote:
>> This patch adds media bus pixel code for the interleaved JPEG/UYVY
>> image format used by S5C73MX Samsung cameras. This interleaved image
>> data is transferred on MIPI-CSI2 bus as User Defined Byte-based Data.
>>
>> It also defines an experimental vendor and device specific media bus
>> formats section and adds related DocBook documentation.
>>
>> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
>> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
>> ---
>>  Documentation/DocBook/media/v4l/compat.xml         |  4 ++
>>  Documentation/DocBook/media/v4l/subdev-formats.xml | 45 +++++++++++++++++++
>>  include/linux/v4l2-mediabus.h                      |  5 +++
>>  3 files changed, 54 insertions(+)
>>
>> diff --git a/Documentation/DocBook/media/v4l/compat.xml
>> b/Documentation/DocBook/media/v4l/compat.xml index 98e8d08..5d2480b 100644
>> --- a/Documentation/DocBook/media/v4l/compat.xml
>> +++ b/Documentation/DocBook/media/v4l/compat.xml
>> @@ -2605,6 +2605,10 @@ ioctls.</para>
>>          <listitem>
>>  	  <para>Support for frequency band enumeration: &VIDIOC-ENUM-FREQ-BANDS;
>> ioctl.</para> </listitem>
>> +        <listitem>
>> +	  <para>Vendor and device specific media bus pixel formats.
>> +	    <xref linkend="v4l2-mbus-vendor-spec-fmts" />.</para>
>> +        </listitem>
>>        </itemizedlist>
>>      </section>
>>
>> diff --git a/Documentation/DocBook/media/v4l/subdev-formats.xml
>> b/Documentation/DocBook/media/v4l/subdev-formats.xml index 49c532e..d7aa870
>> 100644
>> --- a/Documentation/DocBook/media/v4l/subdev-formats.xml
>> +++ b/Documentation/DocBook/media/v4l/subdev-formats.xml
>> @@ -2565,5 +2565,50 @@
>>  	</tgroup>
>>        </table>
>>      </section>
>> +
>> +    <section id="v4l2-mbus-vendor-spec-fmts">
>> +      <title>Vendor and Device Specific Formats</title>
>> +
>> +      <note>
>> +	<title> Experimental </title>
> 
> I don't think you need spaces across the title.

Thanks for spotting this, I'll fix it and any other occurrences there.

>> +	<para>This is an <link linkend="experimental">experimental</link>
>> +interface and may change in the future.</para>
>> +      </note>
>> +
>> +      <para> This section lists complex data formats that are either vendor
>> or
>> +	device specific. These formats comprise raw and compressed image data
>> +	and optional meta-data within a single frame.
> 
> That's currently true, but we could have other strange vendor-specific formats 
> that don't interleave raw and compressed frames.

OK, let me remove that sentence then.

>> +      </para>
>> +
>> +      <para>The following table lists the existing vendor and device
>> specific
>> +	formats.</para>
>> +
>> +      <table pgwide="0" frame="none"
>> id="v4l2-mbus-pixelcode-vendor-specific"> +	<title>Vendor and device
>> specific formats</title>
>> +	<tgroup cols="3">
>> +	  <colspec colname="id" align="left" />
>> +	  <colspec colname="code" align="left"/>
>> +	  <colspec colname="remarks" align="left"/>
>> +	  <thead>
>> +	    <row>
>> +	      <entry>Identifier</entry>
>> +	      <entry>Code</entry>
>> +	      <entry>Comments</entry>
>> +	    </row>
>> +	  </thead>
>> +	  <tbody valign="top">
>> +	    <row id="V4L2-MBUS-FMT-S5C-UYVY-JPG-1X8">
>> +	      <entry>V4L2_MBUS_FMT_S5C_UYVY_JPG_1X8</entry>
>> +	      <entry>0x8001</entry>
>> +	      <entry>
>> +		Interleaved raw UYVY and JPEG image format with embedded
>> +		meta-data, produced by S3C73M3 camera sensors.
>> +	      </entry>
>> +	    </row>
>> +	  </tbody>
>> +	</tgroup>
>> +      </table>
>> +    </section>
>> +
>>    </section>
>>  </section>
>> diff --git a/include/linux/v4l2-mediabus.h b/include/linux/v4l2-mediabus.h
>> index 5ea7f75..b98c566 100644
>> --- a/include/linux/v4l2-mediabus.h
>> +++ b/include/linux/v4l2-mediabus.h
>> @@ -92,6 +92,11 @@ enum v4l2_mbus_pixelcode {
>>
>>  	/* JPEG compressed formats - next is 0x4002 */
>>  	V4L2_MBUS_FMT_JPEG_1X8 = 0x4001,
>> +
>> +	/* Vendor specific formats - next is 0x8002 */
> 
> Anything wrong with 0x5000 as a base value ? :-)

I think I was originally using this value but during discussions
the conclusion was to clearly separate this new range. I have no
strong preference, I'm going to revert it to 0x5000 in the next
iteration, unless someone raises objections.

>> +
>> +	/* S5C73M3 interleaved UYVY and JPEG */
>> +	V4L2_MBUS_FMT_S5C_UYVY_JPEG_1X8 = 0x8001,
>>  };
>>
>>  /**
> 

Regards,
-- 
Sylwester Nawrocki
Samsung Poland R&D Center