Re: PROBLEM: DWC3 USB 3.0 not working on Odroid-XU4 with Exynos 5422

["Michael Niewöhner" <linux@mniewoehner.de>]

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Hi Mathias,
On Mo, 2016-08-29 at 13:59 +0300, Mathias Nyman wrote:
> On 29.08.2016 10:28, Felipe Balbi wrote:
> > 
> > 
> > Hi,
> > 
> > Michael Niewöhner <linux@mniewoehner.de> writes:
> > > 
> > > [1.] One line summary of the problem:
> > > DWC3 USB 3.0 not working on Odroid-XU4 with Exynos 5422
> > > 
> > > [2.] Full description of the problem/report:
> > > No usb 3.0 devices are being detected when attached while USB 2.0
> > > devices work on the same port.
> > > USB 3.0 works after applying patches [9.1] and [9.2], but seems
> > > to be
> > > buggy. The usb hub is redetected every time an usb device is
> > > attached.
> > 
> > dwc3 is host, which means it's actually XHCI :-)
> > 
> > Adding Mathias
> > 
> > > 
> > > dmesg:
> > > [  192.287080] usb 3-1.2: USB disconnect, device number 7
> > > [  210.370699] hub 3-1:1.0: hub_ext_port_status failed (err =
> > > -71)
> 
> Looks like the hub GetPortStatus request fails with protocol error.
> 
> Reading xhci root hub port status is mostly just register reads and
> writes. It
> shouldn't include any actual transfers that could return -EPROTO
> 
> So this is not the root hub? but a external or integrated on your
> board, right?
> 
> The protocol error -71 is returned at transfer errors or if device
> stalled.
> 
> Adding more xhci debugging options could show something:
> echo -n 'module xhci_hcd =p' >
> /sys/kernel/debug/dynamic_debug/control
> 
> > 
> > > 
> > > [9.] Other notes, patches, fixes, workarounds:
> > > [9.1] https://lkml.org/lkml/2014/4/28/234
> > > [9.2] https://lkml.org/lkml/2015/2/2/259
> 
> The additional patches that makes things somehow work involve tuning
> the PHY,
> this is an area I'm not familiar with
> 
> -Mathias
> 


I'm sorry, I should have said that this is the dmesg output with the
patches applied. Without them there is no output at all when I attach
an usb 3.0 device.

Michael

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