On Thu, 16 Mar 2017, Mason wrote: > About shared ISRs. Are they supposed to return IRQ_HANDLED > if and only if they handled something? Every interrupt handler is supposed to return IRQ_NONE if it did not handle it. That does not depend on shared or not. The handler does not know if it's on a shared interrupt line or not. IRQF_SHARED only tells, that the handler is capable of sharing the interrupt line with another device. > Will that stop the next ISR from being called? No. > I guess if two interrupts fire at the same time, we'll just take two > separate exceptions? Wrong guess. That might work with level interupts, but with other types nothing will raise another exception. Sharing interrupts on edge types is a stupid idea, but hardware folks insist on implementing stupid ideas. Thanks, tglx
