On Tue, Oct 3, 2017 at 7:22 PM, Doug Berger [off-list ref] wrote:

On 10/03/2017 07:10 PM, Gregory Fong wrote:

quoted

Hi Doug,

On Fri, Sep 29, 2017 at 8:40 PM, Doug Berger [off-list ref] wrote:

quoted

Mask the GPIO interrupt while its type is being changed, just in case
it can prevent a spurious interrupt.

"Just in case"?  I don't have access to hardware documentation for
this anymore, but I'd expect to some stronger claim that the hardware
actually requires masking before changing the trigger type.  If you
can quote documentation for this or explain an actual problem seen,
that would be good.

Well spotted ;).  This was a protectionist change added at the request
of a user of the driver.  I believe that it is superfluous and I suppose
that belief leaked through in the language of my comment.

In actuality, the GPIO APIs don't make provision for clearing GPIO
interrupts before enabling them so this masking is really only a
deferral of a spurious interrupt if one is triggered by changes in the
hardware programming.

Indeed.  If the hardware is behaving in unexpected ways that would be
a whole different kind of problem.

I can strike this from the upstream submission and save a couple lines
of source code (after IRQCHIP_MASK_ON_SUSPEND goes away) if you prefer.

Yes, please remove.

Thanks,
Gregory