Hi Grant,

On 09/29/2011 08:27 PM, Grant Likely wrote:

On Wed, Sep 28, 2011 at 08:52:30PM +0000, Tabi Timur-B04825 wrote:

quoted

On Tue, Sep 27, 2011 at 1:29 PM, Grant Likely[off-list ref]  wrote:

quoted

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

I was wondering about that.

What exactly is a chained handler?  How is it different from a regular handler?

A chained handler has an expedited path through the interrupt code for
handling it (basically, it skips handling it at the parent controller
and passes through to the child, but it cannot handle multiple chained
children on a single irq input.

g.

I may be missing something, but please see this discussion:
http://comments.gmane.org/gmane.linux.ports.arm.kernel/76025

Chained handler is suggested as the solution for very similar problem.
(several peripherals sharing the same hardware IRQ line. If it's possible
on ARM, it should be doable on powerpc, right ?

Felix.