GPIO IRQ on P1022

[Wolfgang Grandegger]

On 07/31/2011 12:38 PM, Felix Radensky wrote:
> Hi,
> 
> I'm running kernel 3.0 on a custom board based on Freescale P1022.
> The interrupt line of on-board FPGA is connected to GPIO2_9. FPGA
> IRQ is level, active low. The GPIOs are mapped like this:
> 
> GPIOs 160-191, /soc at ffe00000/gpio-controller at f200:
> 
> GPIOs 192-223, /soc at ffe00000/gpio-controller at f100:
> 
> GPIOs 224-255, /soc at ffe00000/gpio-controller at f000:
> 
> I've verified that pin mixing is done correctly, and the
> FPGA IRQ line is indeed configured as GPIO.
> 
> I have the following code in my driver:
> 
>     #define FPGA_IRQ_GPIO 169
> 
>     err = gpio_request(FPGA_IRQ_GPIO, "FPGA IRQ");
>     if (err) {
>         printk(KERN_ERR "Failed to request FPGA IRQ GPIO, err=%d\n", err);
>         goto out;
>     }
> 
>     gpio_direction_input(FPGA_IRQ_GPIO);
> 
>     irq = gpio_to_irq(FPGA_IRQ_GPIO);
>     if (irq < 0) {
>         printk(KERN_ERR "Failed to map FPGA GPIO to IRQ\n");
>         goto out;
>     }
> 
>     err = request_irq(irq, gsat_interrupt,
>               IRQF_TRIGGER_FALLING, DRVNAME, priv);
> 
>     Interrupt handler reads FPGA interrupt status register to clear
> interrupt
>     and exits.
> 
>     What happens when I load my driver is single execution of interrupt
> handler
>     followed by system freeze. Even if I call disable_irq() in interrupt
> handler the
>     system still freezes.

Try disable_irq_nosync() instead.

Wolfgang.