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From: David Brownell <david-b@pacbell.net>
To: Anton Vorontsov <avorontsov@ru.mvista.com>
Subject: Re: [PATCH 2/6] usb/fsl_qe_udc: Fix recursive locking bug in
	ch9getstatus()
Date: Mon, 17 Nov 2008 17:59:42 -0800
References: <20081111160153.GA12783@oksana.dev.rtsoft.ru>
	<20081111160327.GB24699@oksana.dev.rtsoft.ru>
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Cc: Greg Kroah-Hartman <greg@kroah.com>, Li Yang <leoli@freescale.com>,
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On Tuesday 11 November 2008, Anton Vorontsov wrote:
> -       spin_lock_irqsave(&udc->lock, flags);
> +       if (lock)
> +               spin_lock_irqsave(lock, flags);

Ugly ugly ugly.  Conditional locking is error prone ... don't.

Couldn't you just have the usb_ep_queue() method wrap lock calls
around a common routine called by that and the status reporting code?

Or just have the status reporting code stuff the two bytes directly
into the FIFO?  (Which is what a lot of other drivers do.)

- Dave