On Mon, 16 May 2016, Mark Brown wrote:
On Mon, May 16, 2016 at 10:20:24AM -0500, Paul Handrigan wrote:
On Fri, 13 May 2016, Mark Brown wrote:
On Fri, May 13, 2016 at 03:50:28PM -0500, Paul.Handrigan@cirrus.com wrote:
- for (i = 0; i < CS35L33_INT_ATTEMPTS; i++) {
/* ack the irq by reading both status registers */Why do we need this...?
The we need to keep handling the unmasked interrupts until they are all cleared. We could get another interrupt while handling the first triggered interrupt, but the interrupt line could be de-asserted due to the read-to-clear nature of the interrupt status registers.
This doesn't follow? Clear to read shouldn't be affected by reading repeatedly, or at least I don't see that helps any problems in a non-racy fashion, and the interrupt subsystem will happily call the handler again if the interrupt reasserts during handling so new interrupts shouldn't be an issue either. New interrupts are an issue for most devices so we really ought to have handling for that in the interrupt subsystem if it's needed, or possibly the usage of the subsystem needs to change to take advantage of preexisting handling...
After taking a closer look at it, it would make sence to remove the for loop. We will still need to attempt clear the unmasked interrupt status bits since it may take a few reads to clear those bits.