All of lore.kernel.org
 help / color / mirror / Atom feed
From: Alan Stern <stern@rowland.harvard.edu>
To: Greg KH <gregkh@linuxfoundation.org>
Cc: James <bjlockie@lockie.ca>, linux-usb <linux-usb@vger.kernel.org>
Subject: Re: problem with USB-C
Date: Wed, 12 Jan 2022 10:40:49 -0500	[thread overview]
Message-ID: <Yd72gTFL0BsC7vtR@rowland.harvard.edu> (raw)
In-Reply-To: <Yd59HLmparwNaok9@kroah.com>

On Wed, Jan 12, 2022 at 08:02:52AM +0100, Greg KH wrote:
> On Tue, Jan 11, 2022 at 07:56:53PM -0500, James wrote:
> > $ lsusb -tv
> > /:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 5000M
> >     ID 1d6b:0003 Linux Foundation 3.0 root hub
> > /:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 480M
> >     ID 1d6b:0002 Linux Foundation 2.0 root hub
> > /:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 10000M
> >     ID 1d6b:0003 Linux Foundation 3.0 root hub
> > /:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/10p, 480M
> >     ID 1d6b:0002 Linux Foundation 2.0 root hub
> >     |__ Port 5: Dev 2, If 0, Class=Human Interface Device, Driver=usbhid,
> > 1.5M
> >         ID 04d9:1503 Holtek Semiconductor, Inc. Keyboard
> >     |__ Port 5: Dev 2, If 1, Class=Human Interface Device, Driver=usbhid,
> > 1.5M
> >         ID 04d9:1503 Holtek Semiconductor, Inc. Keyboard
> >     |__ Port 6: Dev 3, If 0, Class=Human Interface Device, Driver=usbhid,
> > 1.5M
> >         ID 30fa:0400
> > 
> > With my USB3 drive plugged in to the USB-C port which is supposed to be
> > USB3.1.
> > https://asrock.com/MB/AMD/B450M%20Pro4/index.us.asp
> > 
> > $ lsusb -tv
> > /:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 5000M
> >     ID 1d6b:0003 Linux Foundation 3.0 root hub
> > /:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 480M
> >     ID 1d6b:0002 Linux Foundation 2.0 root hub
> > /:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 10000M
> >     ID 1d6b:0003 Linux Foundation 3.0 root hub
> > /:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/10p, 480M
> >     ID 1d6b:0002 Linux Foundation 2.0 root hub
> >     |__ Port 1: Dev 4, If 0, Class=Mass Storage, Driver=uas, 480M
> >         ID 0bc2:2321 Seagate RSS LLC Expansion Portable

Is that Seagate storage device really supposed to be USB-3.1?  It is 
connected at only USB-2 speed!  Maybe something is wrong with the drive 
or the cable.

> >     |__ Port 5: Dev 2, If 0, Class=Human Interface Device, Driver=usbhid,
> > 1.5M
> >         ID 04d9:1503 Holtek Semiconductor, Inc. Keyboard
> >     |__ Port 5: Dev 2, If 1, Class=Human Interface Device, Driver=usbhid,
> > 1.5M
> >         ID 04d9:1503 Holtek Semiconductor, Inc. Keyboard
> >     |__ Port 6: Dev 3, If 0, Class=Human Interface Device, Driver=usbhid,
> > 1.5M
> >         ID 30fa:0400
> > 
> > 
> > Why are the hubs listed as Linux Foundation 3.0 root hubs and not 3.1 root
> > hubs?
> 
> Because your devices do not advertise themselves as a USB 3.1 root hub.
> Perhaps the documentation is incorrect?

No, that's not it at all.

The reason why the root hubs for buses 2 and 4 above are both listed as 
"Linux Foundation 3.0 root hub" is because in hcd.c, the 
usb31_rh_dev_descriptor and usb3_rh_dev_descriptor structures both set 
their idProduct values to 0x03, 0x00 (0x0003 in little-endian form).  
Therefore the hardware database can't distinguish between them.

One possibility would be for the usb31_rh_dev_descriptor to use 0x04, 
0x00 (with the corresponding update to the udev hardware database).  
Another possibility is for the hardware database entry for product 0x0003
to be changed simply to "Linux Foundation USB-3 root hub", so that it 
doesn't specify 3.0, 3.1, or 3.2.

Alan Stern

  reply	other threads:[~2022-01-12 15:41 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-12  0:56 problem with USB-C James
2022-01-12  7:02 ` Greg KH
2022-01-12 15:40   ` Alan Stern [this message]
2022-01-12 19:39     ` James
2022-01-13  8:40     ` Greg KH

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=Yd72gTFL0BsC7vtR@rowland.harvard.edu \
    --to=stern@rowland.harvard.edu \
    --cc=bjlockie@lockie.ca \
    --cc=gregkh@linuxfoundation.org \
    --cc=linux-usb@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.