Re: Threaded irq handler question

From: Will Newton
Date: Thu Apr 22 2010 - 06:51:20 EST


On Thu, Apr 22, 2010 at 2:37 AM, Yong Zhang <yong.zhang@xxxxxxxxxxxxx> wrote:
> On Wed, Apr 21, 2010 at 05:35:32PM +0100, Will Newton wrote:
>> Hi all,
>> My problem is that this structure does not work, because once I call
>> disable_irq_nosync() on the irq in the check handler the thread will
>> no longer run because the irq is disabled. However if I don't call
>> disable_irq_nosync() I will get endless irqs because the line is
>> level-triggered and will not be deasserted until the thread has run.
>>
>> Could someone tell me what I'm doing wrong here?
>
> Does IRQF_ONESHOT meet your need?

Almost I think, but I believe if my check handler does not wake the
thread then I don't get another interrupt ever. I can fix this by
making my check handler always return WAKE_THREAD, which is slightly
sub-optimal, but not a big problem.

Thank you for your help!
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