Re: uvcvideo: Failed to submit URB 0 (-28) with Cam Sync HD VF0770 (041e:4095)

["Piotr Król" <piotr.krol@3mdeb.com>]

On Tue, Aug 09, 2016 at 01:02:31AM +0200, Piotr Król wrote:
> On Sat, Aug 06, 2016 at 04:00:22PM +0200, Piotr Król wrote:
> > Hi all,
> 
> Hi Hans, Igor,

+Igor

> I found your discussion about very similar issue here [5]. It looks
> like musb driver in host mode doesn't give enough bandwidth for USB
> camera in my case.
> 
> We tested USB device and getting not so bad results for bulk endpoint
> read (15MB/s) and write (1.8MB/s). I'm not sure, if this numbers make
> sense for isochronous endpoint, but it seems there is enough bandwidth
> for video data transfer.
> 
> Full dmesg can be found here [6]
> 
> Have you got any ideas what maybe wrong ? Does it make sense to use musb
> in host mode to transfer video stream ?
> 
> Any help appreciated.
> 
> > We have custom Allwinner A20 based hardware on which we try to utilize
> > USB DRD (configured in device tree as host [1]) to connect Creative web
> > camera [2].
> > 
> > We use 4.7 kernel release built using buildroot. Hardware configuration can
> > be described like that:
> > 
> > A20 mainboard -> LAN9514i -> Creative web camera
> > 
> > I tried v4l2grab and fswebcam, but both application result in
> > "uvcvideo: Failed to submit URB 0 (-28)" and further complaining that
> > there is no space left on device, despite there is planty of free
> > space [3]. We also tried to capture in /tmp with the same result.
> > 
> > v4l2grab output:
> > # v4l2grab -d /dev/video0 -o image.jpg
> > [ 1802.800160 ] uvcvideo: Failed to submit URB 0 (-28).
> > libv4l2: error turning on stream: No space left on device
> > VIDIOC_STREAMON error 28, No space left on device
> > 
> > fswebcam output:
> > # fswebcam -r 1280x720 --jpeg 95 -D 1 image.jpg
> > --- Opening /dev/video0...
> > Trying source module v4l2...
> > /dev/video0 opened.
> > No input was specified, using the first.
> > Delaying 1 seconds.
> > [  432.952080 ] uvcvideo: Failed to submit URB 0 (-28).
> > Error starting stream.
> > VIDIOC_STREAMON: No space left on device
> > Unable to use mmap. Using read instead.
> > Unable to use read.
> > 
> > What we also tried is checking camera with Raspberry Pi Compute Module
> > in that way:
> > 
> > RPICM -> LAN9514i -> LAN9514i -> Creative web camera
> > 
> > And this works without problem.
> > 
> > We proved that USB was correctly configured in host mode by trying
> > usb-storage, usbhid and ftdi driver, what can be found in dmesg [4].
> > 
> > I have hard time with finding from what code -28 came from, since calls
> > are nested in usb subsystem. What this error means ? How it can be
> > avoided ?
> > 
> > Any other ideas how to debug this issue further are welcome.
> > 
> > [1] http://paste.ubuntu.com/22446905/
> > [2] http://www.scanmalta.com/scanshop/creative-live-cam-sync-1-3mp-hd-webcam.html
> > [3] http://paste.ubuntu.com/22448114/
> > [4] http://paste.ubuntu.com/22446585/
> 
> [5] https://groups.google.com/d/msg/linux-sunxi/-O3GckFuje8/aTAkPk1JCQAJ
> [6] http://paste.ubuntu.com/22747309/
> > 
> > -- 
> > Best Regards,
> > Piotr Król
> > Embedded Systems Consultant
> > http://3mdeb.com | @3mdeb_com
> 
> -- 
> Best Regards,
> Piotr Król
> Embedded Systems Consultant
> http://3mdeb.com | @3mdeb_com

-- 
Best Regards,
Piotr Król
Embedded Systems Consultant
http://3mdeb.com | @3mdeb_com