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From: Oliver Neukum <Oliver.Neukum@lrz.uni-muenchen.de>
To: Abramo Bagnara <abramo@alsa-project.org>,
        Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: Is it useful to support user level drivers
Date: Thu, 21 Jun 2001 23:09:04 +0200
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Cc: "D.A.Fedorov@inp.nsk.su Balbir Singh" <balbir_soni@yahoo.com>,
        linux-kernel@vger.kernel.org
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> Kernel space:
> - irq 9 arrives from our device
> - interrupts are disabled
> - our kernel space micro handler is invoked
> - interrupt source is checked
> - if no notification is pending a signal is notificated for user space
> (or a process is marked runnable)
> - optionally our device interrupt generation is disabled
> - handler returns
> - interrupts are enabled

Then why bother ? Write a minimum conventional kernel driver implementing 
poll()

	Regards
		Oliver