Hi Mauro, On Tuesday, 8 January 2019 20:49:16 EET Mauro Carvalho Chehab wrote: > Em Tue, 8 Jan 2019 21:11:41 +0500 Mikhail Gavrilov escreveu: > > On Tue, 8 Jan 2019 at 20:57, Laurent Pinchart wrote: > >> Thank you. > >> > >> Your device exposes five formats: YUY2 (YUYV), YV12 (YVU420), NV12, P010 > >> and BGR3 (BGR24). They are all supported by V4L2 and the uvcvideo > >> driver except for the P010 format. This would be easy to fix in the > >> uvcvideo driver if it wasn't for the fact that the P010 format isn't > >> support by V4L2. Adding support for it isn't difficult, but I don't > >> have time to do this myself at the moment. Would you consider > >> volunteering if I guide you ? :-) > > > > Sure, I'd be happy to help. What is required of me? > > It shouldn't be hard. Thank you for the detailed and clear explanation. > First, you need to add the new format at include/uapi/linux/videodev2.h, > like this one: > > #define V4L2_PIX_FMT_YUV420M v4l2_fourcc('Y', 'M', '1', '2') /* 12 YUV420 > planar */ > > Please put it together with the other YUV formats. > > As the fourcc "P010" was not used on Linux yet, you could use it, > e. g., something like: > > #define V4L2_PIX_FMT_YUV_P10 v4l2_fourcc('P', '0', '1', '0') /* 10 YUV420 > planar */ > > You need then to document it. Each V4L2 format should have a description, > like this: > > https://linuxtv.org/downloads/v4l-dvb-apis-new/uapi/v4l/pixfmt-yuv420m.html > > This is generated via a text file (using ReST syntax). On the above example, > it is produced by this file: > > https://git.linuxtv.org/media_tree.git/tree/Documentation/media/uapi/v4l/pi > xfmt-yuv420m.rst > > Writing it would take a little more time, but, provided that you don't > copy what's written from external docs, you could take a look at the > Internet for the P010 descriptions, and use the pixfmt-yuy420m.rst file > as the basis for a new pixfmt-p010.rst file. > > This will produce a patch similar to this one: > > https://git.linuxtv.org/media_tree.git/commit/?id=5df082e2312c > > Finally, you need to teach the uvc driver that it should report P010 > format, instead of 0x00000000, by adding it at uvc_format_desc uvc_fmts, > with the corresponding UVC GUID. We usually do this on a separate patch. > Something like this: > > https://git.linuxtv.org/media_tree.git/commit/?id=6ea0d588d35b > > Once you have the patches, submit it to the ML :-) > > You could take a look at the LinuxTV wiki page about how to submit, > at the developer's section: > > https://linuxtv.org/wiki/index.php/Developer_section > > In particular, take a look at "Submitting Your Work" section there. -- Regards, Laurent Pinchart