From: "Rémi Denis-Courmont" <remi@remlab.net>
To: linux-media@vger.kernel.org
Subject: uvcvideo USERPTR mode busted?
Date: Sun, 3 Mar 2013 11:37:44 +0200 [thread overview]
Message-ID: <201303031137.44917@leon.remlab.net> (raw)
Hello,
Trying to use USERPTR buffers with UVC, user space gets stuck either in
poll(POLLIN) or in ioctl(VIDIOC_DQBUF). It seems the UVC driver never ever
returns a frame in USERPTR mode. The symptoms are identical with kernel
versions 3.6, 3.7 and 3.8. I also tested 3.2, but it did not support USERPTR.
Tested hardware was Logitech HD Pro Webcam C920 with YUY2 pixel format. The
same hardware and the same driver work fine with MMAP buffers.
The same USERPTR userspace code works fine with the vivi test device...
Did any have any better luck?
--
Rémi Denis-Courmont
http://www.remlab.net/
next reply other threads:[~2013-03-03 9:37 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-03 9:37 Rémi Denis-Courmont [this message]
2013-03-03 14:57 ` uvcvideo USERPTR mode busted? Devin Heitmueller
2013-03-21 12:41 ` Laurent Pinchart
2013-03-21 13:28 ` Devin Heitmueller
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