Re: Handling multiple GPIO controllers in 8xxx GPIO driver

On Tue, Sep 27, 2011 at 04:59:28PM +0300, Felix Radensky wrote:

Hi,

Looks like  8xxx GPIO driver cannot properly handle interrupts
when multiple GPIO controllers exist in the system.

On Freescale P1022 there are 3 GPIO controllers. All 3 use
the same interrupt line, internal interrupt 31. If all controllers
are defined in device tree set_irq_chained_handler() is invoked
3 times with same  hardware irq number. The result is interrupt
storm,  mpc8xxx_gpio_irq_cascade() is invoked indefinitely.

What would be the best way to fix the problem ?

The solution is to make the gpio driver register as a regular
interrupt handler, and not as a chained handler.

g.