On Thu, Jan 21, 2016 at 11:26:11AM +0100, Lothar Waßmann wrote: > > On Thu, Jan 21, 2016 at 08:05:24AM +0100, Lothar Waßmann wrote: > > > > On Wed, Jan 20, 2016 at 01:29:51PM +0100, Lothar Waßmann wrote: > > > > > This pin is used as IRQ pin for the LTC3589 PMIC on the Ka-Ro > > > > > electronics TX48 module. Make the IRQ optional in the driver and use a > > > > > polling routine instead if no IRQ is specified in DT. > > > > > Otherwise the driver will continuously generate interrupts and make > > > > > the system unusable. > > > > How will the driver generate interrupts if there is no interrupt > > > > physically present in the system? > > > It's using timer interrupts to poll the LTC3589 state. > > I know that is what your patch does, my question is why you say in your > > commit log that "Otherwise the driver will continuously generate > > interrupts and make the system unusable". > Because the interrupt is level triggered and the polarity of the > EXTINT pin is inverted, the interrupt will be constantly active when > the IRQ pin of the LTC3589 is inactive. So, to repeat my original question, how will that generate interrupts if there is no interrupt physically present in the system?
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