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From: Grant Edwards <grant.b.edwards@gmail.com>
To: linux-serial@vger.kernel.org
Subject: Re: What to set uart_port->irq to for polled driver?
Date: Thu, 28 Feb 2013 18:43:28 +0000 (UTC)	[thread overview]
Message-ID: <kgo8gf$b1e$1@ger.gmane.org> (raw)
In-Reply-To: 1362076338.3337.3.camel@thor.lan

On 2013-02-28, Peter Hurley <peter@hurleysoftware.com> wrote:
> On Wed, 2013-02-13 at 15:24 +0000, Grant Edwards wrote:
>> For a polled serial driver that doesn't use interrupts, to what should
>> the "irq" field in the uart_port structure be set?  Should it be 0?
>> Should it be the unused IRQ associated with the PCI card slot in which
>> the board is found?
>
> Doesn't look supported, but adding the support doesn't look difficult.
> At the very least, a patch is required so that on port shutdown, the
> core doesn't synchronize_irq().

Does the call ty synchronize_irq() do any harm? AFAICT, it will just
cause a short delay if handling of that IRQ is in-progress.

I currently set the "irq" field to the IRQ number that would be used
by the board if I did choose to enable interrupts. That seems to work
fine (with rather limited testing).

-- 
Grant Edwards               grant.b.edwards        Yow! We just joined the
                                  at               civil hair patrol!
                              gmail.com            


  reply	other threads:[~2013-02-28 18:43 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-02-13 15:24 What to set uart_port->irq to for polled driver? Grant Edwards
2013-02-28 18:32 ` Peter Hurley
2013-02-28 18:43   ` Grant Edwards [this message]
2013-02-28 20:16     ` Peter Hurley
2013-02-28 20:42       ` Grant Edwards

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