From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ming Lei <ming.lei@canonical.com>
Subject: Re: [PATCH 1/2] usbnet: allow status interrupt URB to always be active
Date: Tue, 15 Jan 2013 09:13:56 +0800
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Cc: Oliver Neukum <oliver@neukum.org>,
	Elina Pasheva <epasheva@sierrawireless.com>,
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	Rory Filer <rfiler@sierrawireless.com>,
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To: Dan Williams <dcbw@redhat.com>
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On Tue, Jan 15, 2013 at 1:23 AM, Dan Williams <dcbw@redhat.com> wrote:
> On Fri, 2013-01-11 at 11:06 +0800, Ming Lei wrote:
>> I am curious who are interested in the 'custom Restart indication'
>> information after the interface is closed.
>
> It's actually before the interface is even opened.  It's really just a
> sync signal that's part of the driver's setup/initialization of the
> device.

OK, got it.

Considered that it is only required by Sierra, could you submit
the status URB in driver->bind and cancel it in driver->reset so
we can avoid touching usbnet core code(one simple change
might be to move init_status() before calling driver->info()
inside usbnet_probe())?

>
>> If sierra_net provides ways(such as read registers) to query the
>> indication event, you can just query the information and setup
>> the device in driver_info->reset() during device open, so you can
>> avoid submitting interrupt URB always.
>
> As far as I know, it does not, or at least Sierra hasn't released such
> information about the firmware API of their devices.

You are unlucky, :-)

In fact, many usbnet devices provide read command to query this kind of
information.


Thanks,
--
Ming Lei