From: Alan Stern <stern@rowland.harvard.edu>
To: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: gregkh@linuxfoundation.org, <linux-usb@vger.kernel.org>,
<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] USB: Wait for extra delay time after USB_PORT_FEAT_RESET for quirky hub
Date: Fri, 19 Oct 2018 10:05:52 -0400 (EDT) [thread overview]
Message-ID: <Pine.LNX.4.44L0.1810191005380.1406-100000@iolanthe.rowland.org> (raw)
In-Reply-To: <20181019081450.21230-1-kai.heng.feng@canonical.com>
On Fri, 19 Oct 2018, Kai-Heng Feng wrote:
> Devices connected under Terminus Technology Inc. Hub (1a40:0101) may
> fail to work after the system resumes from suspend:
> [ 206.063325] usb 3-2.4: reset full-speed USB device number 4 using xhci_hcd
> [ 206.143691] usb 3-2.4: device descriptor read/64, error -32
> [ 206.351671] usb 3-2.4: device descriptor read/64, error -32
>
> Info for this hub:
> T: Bus=03 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#= 2 Spd=480 MxCh= 4
> D: Ver= 2.00 Cls=09(hub ) Sub=00 Prot=01 MxPS=64 #Cfgs= 1
> P: Vendor=1a40 ProdID=0101 Rev=01.11
> S: Product=USB 2.0 Hub
> C: #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=100mA
> I: If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub
>
> Some expirements indicate that the USB devices connected to the hub are
> innocent, it's the hub itself is to blame. The hub needs extra delay
> time after it resets its port.
>
> Hence wait for extra delay, if the device is connected to this quirky
> hub.
>
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> ---
> v2:
> - Use hub->hdev to check quirk.
> - Merge the delay with TRSTRCY.
Acked-by: Alan Stern <stern@rowland.harvard.edu>
prev parent reply other threads:[~2018-10-19 14:05 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-19 8:14 [PATCH v2] USB: Wait for extra delay time after USB_PORT_FEAT_RESET for quirky hub Kai-Heng Feng
2018-10-19 14:05 ` Alan Stern [this message]
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=Pine.LNX.4.44L0.1810191005380.1406-100000@iolanthe.rowland.org \
--to=stern@rowland.harvard.edu \
--cc=gregkh@linuxfoundation.org \
--cc=kai.heng.feng@canonical.com \
--cc=linux-kernel@vger.kernel.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).