From: Stephen Warren <swarren@wwwdotorg.org>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: Venu Byravarasu <vbyravarasu@nvidia.com>,
gregkh@linuxfoundation.org, linux-usb@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] usb: host: tegra: Reset Tegra USB controller before init
Date: Thu, 28 Feb 2013 11:10:24 -0700 [thread overview]
Message-ID: <512F9D90.7090705@wwwdotorg.org> (raw)
In-Reply-To: <Pine.LNX.4.44L0.1302281003340.1352-100000@iolanthe.rowland.org>
On 02/28/2013 08:09 AM, Alan Stern wrote:
> On Thu, 28 Feb 2013, Venu Byravarasu wrote:
>
>> To clear any configurations made by U-Boot on Tegra USB controller,
>> reset it before init in probe.
>>
>> Signed-off-by: Venu Byravarasu <vbyravarasu@nvidia.com>
>> ---
>> When U-Boot configures a Tegra USB controller in device mode and if the EHCI
>> driver of kernel tries to set it to HOST mode, message "irq 52: nobody cared"
>> appears and IRQ gets disabled.
>>
>> This issue was initially reported with: http://marc.info/?l=linux-tegra&m=136110175423601&w=2
>>
>> To avoid such issues, due to configurations made by U-Boot driver, reset the
>> Tegra USB controller, before configuring it by kernel.
>
> Does the Tegra platform use shared interrupts? If it does, what
> happens if the IRQ is enabled and in use by another device before
> ehci-tegra resets the USB controller?
I believe there's a dedicated interrupt just for each individual controller.
next prev parent reply other threads:[~2013-02-28 18:10 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-28 6:36 [PATCH] usb: host: tegra: Reset Tegra USB controller before init Venu Byravarasu
2013-02-28 15:09 ` Alan Stern
2013-02-28 18:10 ` Stephen Warren [this message]
2013-02-28 18:16 ` Stephen Warren
2013-02-28 18:52 ` Alan Stern
2013-02-28 19:11 ` Stephen Warren
2013-03-04 7:55 ` Venu Byravarasu
2013-03-04 16:55 ` Stephen Warren
2013-03-04 17:38 ` Alan Stern
2013-03-05 0:34 ` gregkh
2013-04-02 7:12 ` Venu Byravarasu
2013-04-02 15:31 ` Stephen Warren
2013-04-03 10:48 ` Venu Byravarasu
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=512F9D90.7090705@wwwdotorg.org \
--to=swarren@wwwdotorg.org \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=stern@rowland.harvard.edu \
--cc=vbyravarasu@nvidia.com \
/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