On Thu, Nov 27, 2014 at 3:36 PM, Alexander Stein <alexander.stein@xxxxxxxxxxxxxxxxxxxxx> wrote: > On Thursday 27 November 2014 14:58:39, Linus Walleij wrote: >> Sorry too confused by this, can you explain? > > Sure. Until now ODR is cleared as reset default while INTPOL explicitly gets cleared. > So the INT output pin on the MCP23S17 is an active-low output pin which will trigger > an active-low interrupt. OK... I thought it was some kind of input line to the device. Now I get it, it is what is generated *out* of this device. Please state this in the bindings. > While this is useually great, as most interrupt pins are active low, our board design > requires an active-high output. OK I get it :) > You might wonder why I then also changed IRQF_TRIGGER_LOW to > IRQF_TRIGGER_HIGH for my board the interrupt line is actually active low. > This is due the fact that GIC only supports active high-interrupts (any other flag > results in request fail) but the microcontroller has a feature to inverse these interrupt triggers. Very convoluted, but common in electronics, OK, no problem. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
