00:47 <jakllsch> hmm, https://centerclick.com/ntp/docs/hardware_220_270

00:47 <jakllsch> T133-S

07:17 <gamiee> jakllsch : that PoE board is manufactured by Banana Pi :D :D

19:53 <valdikss> Hey everybody, the USB 1.1 Full Speed transfers on Orange Pi Zero3 (Allwinner H618) seems to be really slow, which causes underruns on my printer. Have to use USB Hub (which does 1.1 translation itself) as a workaround. Known issue?

22:53 <apritzel> valdikss: what does "slow" mean, exactly? What is the device? And what is the transfer type, bulk? I wouldn't remember similar reports, but then again it's probably more about HighSpeed when it comes to performance.

23:00 <valdikss> apritzel: I just tested several SBCs, including rockchip-based, and I see this issue on all tested devices. It could be that Linux OHCI is inefficient, or some other bug.

23:01 <valdikss> apritzel: My current testing device is Orange Pi Zero3, and the printer is Canon LBP1120. I have a small "speed test" script, here's the numbers I got:

23:02 <valdikss> https://paste.centos.org/view/8abddff0

23:03 <valdikss> This printer has a rather small internal buffer and relies on data streaming while printing. And I can't print large lists with the direct connection because the printer reports underflow. Works fine with USB hub.

23:04 <valdikss> No errors on USB level, I checked with tcpdump -i usbmon0. I had issues with bad cables before, and it was seen as a transcation error in the log, but here everything is fine, it's just the USB is not fast enough.

23:05 <valdikss> Linux kernel docs on EHCI https://docs.kernel.org/usb/ehci.html says the following:

23:05 <valdikss> USB 1.1 devices may also be used on USB 2.0 systems. When plugged into an EHCI controller, they are given to a USB 1.1 “companion” controller, which is a OHCI or UHCI controller as normally used with such devices. When USB 1.1 devices plug into USB 2.0 hubs, they interact with the EHCI controller through a “Transaction Translator” (TT) in the hub, which turns low or full speed transactions into high speed “split transactions” that don’t

23:05 <valdikss> waste transfer bandwidth.

23:05 <valdikss> So I guess it is it.

23:07 <valdikss> apritzel: The transfer type is bulk, yes.

23:08 <apritzel> ah, you mean a classic "paper printer", I was assuming a 3D printer ;-)

23:10 <apritzel> but that sounds like a more generic Linux problem, you might want to ask on the USB mailing list, there are surely more experts on there

23:22 <valdikss> apritzel: that's a really old printer from 2002, yeah

23:38 <apritzel> it could be a clock issue, since there is a separate 12MHz clock for OHCI, but we don't have much control over it, and that surely wouldn't be the same issue on Rockchip then