[Open-graphics] Video interrupt enable/disable

[Jan Knutar]

On Thursday 19 April 2007 01:44, James Richard Tyrer wrote:

> >> If the interrupt is the same for sync and service request, then
> >> the driver will have to read two status register bits to see which
> >> interrupt is set before the interrupt is serviced and then write
> >> back to clear the interrupt.
> >
> > Chances are you're going to have to do that anyway because you
> > might be on a shared interrupt line.
>
> IIUC, shared PCI interrupts are handled by a Kernel driver.  It is
> transparent to the device driver for the PCI card.

I've understood it that the kernel has no way of knowing which device 
triggered the interrupt. It simply calls the interrupt handler for 
every device on that IRQ. The device drivers must then query the 
hardware..