Date: Thu, 17 Jan 2013 06:39:46 +0100 (CET) From: "Jakob Alvermark" <jakob@alvermark.net> To: "Oleksandr Tymoshenko" <gonzo@bluezbox.com> Cc: freebsd-arm@freebsd.org, Jakob Alvermark <jakob@alvermark.net> Subject: Re: Isochronous USB transfers on RPI? Message-ID: <29663.85.229.93.180.1358401186.squirrel@webmail.alvermark.net> In-Reply-To: <50F73F19.20401@bluezbox.com> References: <6BD0E5E4-3921-4F9B-9381-3813933670AE@alvermark.net> <201301161319.17236.hselasky@c2i.net> <78AB4FEC-6E16-4FCA-B172-3C7B37FEA4DF@alvermark.net> <50F73F19.20401@bluezbox.com>
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On Thu, January 17, 2013 01:00, Oleksandr Tymoshenko wrote: > On 1/16/2013 6:29 AM, Jakob Alvermark wrote: > >> Hi, >> >> >> I see that there is code, I'm not just very good at reading and writing >> it. :-) >> >> usbdump is quiet on the Pi On my laptop I can see ISOC packets when >> using the same webcam and software so something is missing. > > I'm not familiar with webcam configuration on freebsd but > do you have all the components setup on RPi? Kernel driver and/or userland > bits? The device is a video grabber with an analog video camera connected. The software is entirely in userland, using libusb. Code is at http://code.google.com/p/easycap-somagic-linux/ I works on my laptop (amd64 with ehci) and comparing output of usbdump while (trying) capturing video, ISOC is completely missing on RPi. >> >> /Jakob >> >> >> On 16 jan 2013, at 13:19, Hans Petter Selasky wrote: >> >> >>> On Wednesday 16 January 2013 10:25:38 Jakob Alvermark wrote: >>> >>>> Hi, >>>> >>>> >>>> Maybe this should go to the usb list, but it is probably relevant >>>> here as well. I have been playing with the Pi for a while now and >>>> having great fun with FreeBSD. Great work gonzo and others! However, >>>> I'd like to use a webcam with it. I learned that USB webcams use >>>> isochronous transfers and the DWC OTG driver doesn't fully implement >>>> it. (If I read the commit logs correctly) >>>> What is missing and how can I help? >>>> >>>> >>> Hi, >>> >>> >>> The DWC OTG driver has not fully implemented isochronous. Using >>> isochronous transfers will have a high CPU load impact, because 1000 >>> IRQ's (FS) or 8000 >>> IRQ's (HS) second will be needed to feed the FIFOs. However, if this >>> is acceptable, code can be found in: >>> >>> sys/dev/usb/controller/dwc_otg.c >>> >>> --HPS >>> >>> >> _______________________________________________ >> freebsd-arm@freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-arm >> To unsubscribe, send any mail to "freebsd-arm-unsubscribe@freebsd.org" >> >> > > >
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