From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
To: Martin Shepherd <mcs@domain.hid>
Cc: xenomai@xenomai.org
Subject: Re: [Xenomai-help] Defensive IRQ allocation procedure.
Date: Mon, 04 May 2009 21:49:15 +0200 [thread overview]
Message-ID: <49FF46BB.8050106@domain.hid> (raw)
In-Reply-To: <Pine.LNX.4.64.0905041110140.10290@domain.hid>
Martin Shepherd wrote:
> Am I correct in believing that an RTDM driver can safely call
> request_irq() from its non-realtime ioctl_nr() callback? I want to do
> this to verify that a non-realtime driver isn't using the same IRQ as
> my realtime device, before I attempt to use it in my RTDM driver, and
> as well as to prevent any non-realtime drivers from allocating that
> IRQ once I have started to use it. I can't do this at module
> initialization time, because I don't know which of our identical
> digital I/O boards is connected to what, until I perform I/O to them,
> and not all of them need interrupts.
Yes, this should work. Note however, that request_irq will work even if
there is another irq handler registered with IRQF_SHARED, and you pass
IRQF_SHARED too.
--
Gilles.
prev parent reply other threads:[~2009-05-04 19:49 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-05-04 19:04 [Xenomai-help] Defensive IRQ allocation procedure Martin Shepherd
2009-05-04 19:49 ` Gilles Chanteperdrix [this message]
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