GPIO interrupts on mpc8313e

Yoni Levin yoni.l at
Fri Aug 3 01:38:52 EST 2007


-----Original Message-----
From: Scott Wood [mailto:scottwood at] 
Sent: Thursday, August 02, 2007 6:19 PM
To: Yoni Levin
Cc: linuxppc-embedded at
Subject: Re: GPIO interrupts on mpc8313e

Yoni Levin wrote:
> Yes, I removed the flag (0) and nothing change in both cases the
> return 0 which is good.
> Then I added enable_irq and I recived :
> Unbalanced enable for IRQ 74

Yeah, sorry, I misremembered what IRQF_DISABLED does.  As Domen pointed 
out, you need to pass myirq, not 74, to request_irq().

> void CreateGPIOHandler()
> {
> 	unsigned int myirq=irq_create_mapping(NULL,74);
> 	enable_irq(74);
> 	printk("myirq is : %d \n",myirq);
> 	int ret;
> 	ret=- request_irq(74, GPIOinterrupt_handler,0, "GPIO", NULL);
> 	printk("ret is : %d \n",ret);
> }

Even if IRQF_DISABLED did do what I thought it did (I was thinking of 
IRQ_NOAUTOEN, which is apparently an ARM-only thing), you should never 
call enable_irq() before request_irq(), or without previously disabling 
it (either explicitly or via IRQ_NOAUTOEN).


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