Re: [PATCH] ARM:mfd: fix ezx-pcap build failure
On Fri, Apr 27, 2012 at 11:28:28AM -0400, Mark Asselstine wrote: On April 26, 2012 22:52:58 Russell King - ARM Linux wrote: What is the effect when the supplied IRQ does not have a mapping to a GPIO - or it _does_ by way of a badly coded irq_to_gpio() function but that GPIO is not the correct one. There is no prevention against endlessly looping, so it could cause a system lockup. Unfortunately the commit [b1148fd4 mfd: fix pcap irq bottom handler ] which modified things to loop as long as the interrupt is asserted didn't supply much information regarding the behavior they were trying to achieve/fix nor what would be the consequence of bailing earlier. The usual reason for this pattern is to simulate level triggered IRQs on an edge triggered interrupt controller.
Re: [PATCH] ARM:mfd: fix ezx-pcap build failure
On Thu, Apr 26, 2012 at 10:52:58PM +0100, Russell King - ARM Linux wrote: The real answer is to fix SPI et.al. so that its possible to pass the _GPIO_ number into this driver (that's what the driver wants for its interrupt line after all). To fix that, SPI folk need to get involved (added Grant as a first step.) Or, in the short term, add platform data to pass in a GPIO and ignore any IRQ that might get passed in.
