Re: [Xenomai-help] Registering Interrupt Handler [Scanned]

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

Niklaus Burren wrote:
> Hello
> 
> I try to register an interrupt handler for an externel interrupt(GPIO 
> 105) in a xenomai (2.2.2) kernel module on a ARM processor (PXA 270).
> I create a interrupt object with the rt_intr_create() function without 
> an error. After that I enable the interrupt with rt_intr_enable(). When 
> I run the kernel module on the PXA270 board and put a square signal to 
> the GPIO 105 pin the interrupt handler is never called.
> 
> // Interrupt Handler
> int int_handler(struct xnintr *intr)
> {
>     printk("Interrupt detected\n");
>     return RT_INTR_HANDLED;
> }
> 
> ----
> 
> // Enalbe Interrupt in init_module()
> err = rt_intr_create(&intr_desc, "GPIO_INT", 10, &int_handler, NULL, NULL);
> 
> rt_intr_enable(&intr_desc);
> 
> On PXA270 all externel interrupts on GPIO's have the same interrupt 
> number (10). Is that a problem? When I get the pin status from the pin 
> level register GPLR3 I can detect the square signal at the pin. But the 
> interrupt handler function int_handler() is never called.

The I-pipe code demultiplexes the IRQ 10 and triggers handlers for irq
numbers after 34. The macro IRQ_GPIO, defined in
include/asm-arm/arch-pxa/irqs.h allow you to get the irq number
associated with a particular GPIO.

So, if you want to be notified of an interrupt on GPIO105, you should
register an handler for irq IRQ_GPIO(105).

-- 
                                                 Gilles Chanteperdrix