Messages in this thread | | | Date | Fri, 23 Apr 2010 14:29:07 +0100 | From | Mark Brown <> | Subject | Re: Threaded irq handler question |
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On Wed, Apr 21, 2010 at 05:35:32PM +0100, Will Newton wrote:
> I have a threaded irq handler attached to a level-triggered gpio > interrupt line. The check handler checks the status of the gpio line > and disables the irq line amd returns WAKE_THREAD in that case:
...
> 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?
The genirq framework has native support for doing this using a oneshot IRQ handler - if you request the IRQ with IRQF_ONESHOT and provide only a threaded IRQ handler then genirq will disable the interrupt when the primary IRQ fires and schedule the threaded handler.
See wm831x or wm8350 for an example.
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