Let me apologize for emailing directly to the list as I'm not one of the developers and just starting out with USB and UVC. After searching online for about a week I just couldn't find answers and I hope the original authors of the uvc-gadget tool are on the list and can help out. Needed to test a UVC in a custom built kernel (Xilinx petalinux), . Followed these directions, https://github.com/torvalds/linux/blob/ef954844c7ace62f773f4f23e28d2d915adc419f/Documentation/usb/gadget-testing.txt#L717-L730. Patches didn't work. Had to look around for correct ones. Found them here, http://markmail.org/message/hb7evzvigbuxptz5#query:+page:1+mid:s73fdeffjgb2v2yw+state:results. Combined and applied the patches into a repo here, https://github.com/cyboflash/uvc-gadget.git. When I ran a test command, given in the instructions above, uvc-gadget -u /dev/video<uvc video node #> -v /dev/video<vivid video node #> got the following error: V4L2_CORE: (jpeg decoder) error while decoding frame and a black screen. One thing to note is that I was not using luvcview, but guvcview. It looks like the error is coming from here, https://sourceforge.net/p/guvcview/git-master/ci/master/tree/gview_v4l2core/jpeg_decoder.c#l1503 My thoughts 1. I don't think the error is coming from v4l2. I tested it on another machine and it worked. But I'm not an expert so I can't say for sure. 2. I don't think the error is coming from UVC. I think since I see a black screen, it is working. Again, I'm not an expert, so I can't say for sure. 3. I think the error is due to uvc-gadget test application. It could be that the applied patches are outdated, but I just didn't find anything else online. But, I'm not an expert so definitely can't say for sure. I would greatly appreciate any help with this as I'm just starting out with UVC and USB. -- *ESENCIA TECHNOLOGIES, INC.*3945 Freedom Circle, Suite #360, Santa Clara CA 95054 ________________________________________________________ Phone: +1 408 736 8284 Fax: +1 408 519 3475 http://www.esenciatech.com | http://www.lnttechservices.com -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
