Hi Mathias, On Mon, 29 Jan 2018 14:02:57 +0200, Mathias Nyman wrote: > On 19.01.2018 22:12, Philipp Zabel wrote: > > Hi, > > > > On Fri, Jan 19, 2018 at 2:10 PM, Michael Tretter > > <m.tretter@xxxxxxxxxxxxxx> wrote: > >> I found the old thread and it sounds exactly like my issue. Different > >> camera, but same xHCI controller. > > > > I have exactly the same issue with the xHCI controller of my laptop and > > "Oculus Sensor" USB3 isochronous mostly-UVC cameras: > > > > 00:14.0 USB controller: Intel Corporation Wildcat Point-LP USB xHCI > > Controller (rev 03) (prog-if 30 [XHCI]) > > Subsystem: Lenovo Wildcat Point-LP USB xHCI Controller > > Flags: bus master, medium devsel, latency 0, IRQ 44 > > Memory at f2220000 (64-bit, non-prefetchable) [size=64K] > > Capabilities: [70] Power Management version 2 > > Capabilities: [80] MSI: Enable+ Count=1/8 Maskable- 64bit+ > > Kernel driver in use: xhci_hcd > > Kernel modules: xhci_pci > > > > T: Bus=02 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 4 Spd=5000 MxCh= 0 > > D: Ver= 3.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS= 9 #Cfgs= 1 > > P: Vendor=2833 ProdID=0211 Rev= 0.00 > > S: Manufacturer=Oculus VR > > S: Product=Rift Sensor > > S: SerialNumber=WMTD3034300BCT > > C:* #Ifs= 2 Cfg#= 1 Atr=80 MxPwr=800mA > > A: FirstIf#= 0 IfCount= 2 Cls=ff(vend.) Sub=03 Prot=00 > > I:* If#= 0 Alt= 0 #EPs= 1 Cls=ff(vend.) Sub=01 Prot=00 Driver=uvcvideo > > E: Ad=83(I) Atr=03(Int.) MxPS= 32 Ivl=128ms > > I:* If#= 1 Alt= 0 #EPs= 0 Cls=ff(vend.) Sub=02 Prot=00 Driver=uvcvideo > > I: If#= 1 Alt= 1 #EPs= 1 Cls=ff(vend.) Sub=02 Prot=00 Driver=uvcvideo > > E: Ad=81(I) Atr=05(Isoc) MxPS=1024 Ivl=125us > > I: If#= 1 Alt= 2 #EPs= 1 Cls=ff(vend.) Sub=02 Prot=00 Driver=uvcvideo > > E: Ad=81(I) Atr=05(Isoc) MxPS=1024 Ivl=125us > > > > Any USB2 or USB3 device that I plug in while the first camera is streaming in > > altsetting 1 or 2 causes the bandwidth error. The same happens when I try to > > change the altsetting on an isochronous endpoint of an already plugged device. > > While the camera is in altsetting 0, other devices can be probed and work. > > > >> For some tests, I changed the xhci_change_max_exit_latency() function > >> to ignore the requested MEL and set the MEL to 0. Now the USB devices > >> are detected correctly. > > > > Exactly the same thing helps here, as well. With this hack, streaming from two > > of those cameras at the same time works without any apparent problem: > > > > ----------8<---------- > > diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c > > index 297536c9fd00..3cb4a60d8822 100644 > > --- a/drivers/usb/host/xhci.c > > +++ b/drivers/usb/host/xhci.c > > @@ -4025,7 +4025,7 @@ static int __maybe_unused > > xhci_change_max_exit_latency(struct xhci_hcd *xhci, > > ctrl_ctx->add_flags |= cpu_to_le32(SLOT_FLAG); > > slot_ctx = xhci_get_slot_ctx(xhci, command->in_ctx); > > slot_ctx->dev_info2 &= cpu_to_le32(~((u32) MAX_EXIT)); > > - slot_ctx->dev_info2 |= cpu_to_le32(max_exit_latency); > > + slot_ctx->dev_info2 |= cpu_to_le32(0); > > slot_ctx->dev_state = 0; > > > > xhci_dbg_trace(xhci, trace_xhci_dbg_context_change, > > ---------->8---------- > > > > Ok, back after a week on sickleave. > I'm getting the magewell capture device and try to reproduce this myself. I don't think that the issue is specific to the magewell capture device, but rather should be reproducible with any USB3 device with isochronous endpoints. Anyway, please tell me, if I can somehow help you to get this properly fixed. Michael -- 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
