Date: Thu, 16 May 2013 19:20:30 +0200
From: Ignacy Gawedzki <i@lri.fr>
To: Oleksij Rempel <linux@rempel-privat.de>
Cc: ath9k-devel@lists.ath9k.org, linux-wireless@vger.kernel.org
Subject: Re: [ath9k-devel] ath9k_htc: Target is unresponsive
Message-ID: <20130516172030.GD21850@zenon.in.qult.net> (sfid-20130516_192037_802567_93CAE604)
References: <20130515134258.GA9033@zenon.in.qult.net>
 <5194DEB3.2060407@rempel-privat.de>
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On Thu, May 16, 2013 at 03:27:15PM +0200, thus spake Oleksij Rempel:
> Am 15.05.2013 15:42, schrieb Ignacy Gawedzki:
> >Hi everyone,
> >
> >This is an old issue, about which it seems the first posts date back to 2009.
> >With the latest possible version of the firmware for AR9271 and the latest
> >possible wireless drivers, the issue is still there.  Whether this is still
> >the exact same problem every time remains to be checked, but it is annoying
> >enough to deserve some consideration.
> >
> >The problem is that the driver can't talk to the device if the following
> >conditions are met:
> >
> >  - The system cold boots with the USB dongle inserted or the USB dongle is
> >    inserted on a running system.
> >
> >  - The interface is *not* brought up.
> >
> >  - The system (warm) reboots.
> >
> >Then the driver complains about the target being unresponsive after uploading
> >the firmware.  Apparently the only way to make it work again is to unplug and
> >then plug the USB dongle back, physically.  It seems that if the USB port is
> >not powered down during reboot (which happens with at least two different
> >setups that I've tested it with), the device is left in a broken state.
> >
> >I would gladly help in tracing down this bug if only I knew where to start.
> >
> >Thanks for any suggestion.
> 
> Hi Ignacy,
> 
> i can't reproduce this issue on my system. I tested it with 4
> different ath9_htc adapter. Without luck.

Without luck, but it seems you're the lucky one anyway. =)

>                                           Please provide as match
> information as possible:
> - Usb host controller

Tested both on Raspberry Pi and on Dell XPS 13.  The latter uses Intel EHCI,
8086:1c2d and Fresco Logic 1b73:1009, I don't know which one is used exactly.

> - Adapter manufacture and version, or even better add it to the
> wiki, and upload some images:
> http://wikidevi.com/wiki/Main_Page

TP-Link TL-WN722NC, exactly as the one on the wiki.

> - your kernel version

Tested with 3.5.0 on XPS and 3.6.11, 3.8.12 and 3.9.2 on RPi (using a
customized buildroot, but I can provide the .config if needed).

> I assume it is not firmware. May be there are some issue with boot
> loader on adapter. Are you sure that UART pins are not soldered?

I opened the dongle, managed to solder the metal shield off and the pins
weren't used (all four 48-51, among others).

> Current ath9k_htc do not have mechanism to reset an adapter. I will
> start to work on it after some other issues are done.

Is it physically possible?

> PS: please find some way to enable uart, at least TX pin.

I tried to solder the TX pin, but it's really too tiny.  I don't have an iron
so small as to be able to do it, sorry.  I would really love to have an UART
connection, but that's just beyond my abilities.  BTW, it would really be
great to have a way to send debug message up the USB link, just as with
carl9170.

Thanks for your help anyway, I hope we'll find a way to make that work.

-- 
Sex on TV doesn't hurt....unless you fall off.