On 25 October 2012 15:26, Hongbo Zhang [off-list ref] wrote:

Verish, see the codes in include/linux/interrupt.h:

s/verish/viresh :)

static inline int __must_check
devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler,
                 unsigned long irqflags, const char *devname, void *dev_id)
{
        return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags,
                                         devname, dev_id);
}
devm_request_irq is devm_request_threaded_irq

See carefully what's happening here.

All interrupt types have a common irq_desc type in kernel. This has
few pointers for every
interrupt line:
- List of handlers to call from interrupt context
- handlers to call from process context via a thread.

So, the internal implementation is exactly same... The only difference
is which pointer
should be called in.

the devm_request_threaded_irq() called from devm_request_irq() has
following params
handler: For irq to be called from interrupt context (param 3)
NULL: For irq to be called from process context. (param 4)

So, that means  normal request_irq type only.

In your case, you have passed interrupt context pointer as NULL and
process context
one as handler. So that's an issue.

--
viresh